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1
System of Pyro Reprocessing
RAW Treatment
Mikhail Kormilitsyn Andrew Lizin Alexander Osipenko
Research Institute of Atomic Reactors
Dimitrovgrad Russia
1
UNF
2wwwrosatomru
INTERACTION OF TERMAL AND FAST REACTORrsquoS FUEL CYCLES
Thermal reactors Fast Reactors
Model of RUSSIANIntegrated UNF Management System for 2025-2030
RBMK7 units
VVER-10001200
30 units(in Russia)
U fuel fab HLW Disposal
Fast Reactor FuelsReprocessing amp Fab
600 t
400 t
MOX-VVER Pu + U
Centralized UNF Storage(up to 30 000 MT HM)
RT-2 LWR UNFReprocessing plant
1000-1700 t of UNFyear
amp MOX Fab
UNF
UNF 250 t
UNF FR (W-Pu)
U-Pu-fuel
UNF
BN-800
BN-1200andor BREST-
1200
Several units
VVER-10001200
20 units(abroad)
U
UNF FR
Dimitrovgrad dry Process (DDP) MOXMOX flow sheet
Cathode(pyrographite)
Stirrer
UO22+
+
Pu4+
UO22+
UO2 PuO2
Cl2 Cl2+O2+ArStirrerCathode
Na3PO4
Fuel chlorination650 оС
pyrographite bathNaCl -2CsCl
Electrolysis-additional 630 оС
Melt purification650 оС
Cl-
(MAREE)RW4
MAREE
UO22+
UO2 +NpO2
Ar (Cl2)
+
Preliminaryelectrolysis
630 оС
NpO2+
UO22+
MOX
Cl2+O2+Ar
+
Main MOXelectrolysis
630 оС
PuO2+
PuO2+
MOX
4
Integrated flow sheet of spent MOX-fuel reprocessing
Freezing ofchlorine
Chlorination Electrolysis of therecovered melt
Precipitativecrystallization
Electrolysis of theoxidized melt
Melt purificationwith phosphate
Removal of captured salts
Cleaning of sublima
Excesschlorine
Off gases
UO2-1 PuO2 UO2-2 Phosphateprecipitate
UO2-1 PuO2 forfabrication of
fuel rods
UO2-2 Phosphateprecipitate
STORAGE STORAGE STORAGE
Spentelectrolyte
Solutions
Concentration of
solutions by
evaporation
Disposal Immobilizationon glass and
ceramics surfaces
Cl2
Off gas
Cl2 absorptionRemoval of
aerosols
Cl2
Off gas
Resultant solution goesinto radioactive drain
Salts
Water
Contaminatedvacuum cleaning
through filters
Gases to the airduct system
Offgases
Sublimates
Cl2
Off Gases
Incineration ofpyrographite
ashes
FuelMechanicaldecladding
Fuel rods
Treatment inthe resin
Decontamination
Disposal
Pyrographitecomponents
Units ofequipment
Metalequipmen
t
Solution
Burnable waste
Resultantsolution goes
into radioactivedrain
Resin
5
Summary of the MOX-fuel reprocessing process andmain types of radioactive waste
The MOX-fuel to be reprocessed is subjected to mechanical decladdinggrinding to a powder and loaded into the head device- chlorator - electrolyserAll the operations of pyroelectrochemical reprocessing are carried out in thedevice The sequence of operations is as follows
Fuel chlorination in molten NaCl-KCl LiCl-NaCl-KCl-СsCl
Electrolysis for removal of UO2-1 with some fission products (FPs)captured by cathodic deposit
Precipitative crystallization of PuO2 decontaminated from FPs and otherimpurities
Additional electrolysis for removal of UO2-2 with deposited FPs and otherimpurities
Molten salt purification by introduction of phosphates into the melt
6
01M HNO3
(3Li-2K)Cl+CdCl2+PuCl3
Fissile material
Fuelregeneration
Cd
Removal of salts
U+Pu+Cd+(3Li-2K)Cl
Partitioning of minoractinides and FP
(3L
i-2
K)C
l+М
А+
ПД
Removal of salts
Bi+МА+(3Li-2K)Cl
Fabrication of targets
Carbonateprecipitation
(3Li-2K)Cl+FP
Na2СO3
Immobilization
Precipitatecollection
(3Li-2K)ClAfter 3 cycles
Precipitatepurification
Condensation ofsolutions by evaporations
Concentration ofsolutions byevaporation
Aqueous solution(3Li-2K)Cl
Precipitate with FP
FP oxides
(3L
i-2
K)C
l
HNO3 dilute solution
Aqueous solution (3Li-2K)Cl
wa
ter
Condensation ofsolutions byevaporations
Aqueous solution (3Li-2K)Cl
(3Li-2K)Cl
РH
NO
3d
ilu
teso
luti
on
Cd sublimationand condensation
U+Pu+Cd
01M HNO3
(3Li-2K)Cl
UP
up
ow
der
Fuel fabrication
UPu
МА
+B
i
ре
ген
ер
Cd
Bi
(3Li-2K)Cl
water
Integrated flowsheet of pyrochemicalreprocessing of dense fuel
7
Summary of the so called ldquodenserdquo SNF (nitride metal) reprocessingprocess and main types of radioactive waste
The basic processes include the following stages of the dense SNFreprocessing
bull Anodic dissolution with cadmium cathode in molten 3LiCl-2KCl
bull Evaporation of liquid cadmium followed by separation fissilematerials for further manufacturing of metallic and nitride fuel
bull MA partitioning from fission products in a liquid metallic cathode
bull Precipitation of REE by Li2O+K2O trough introduction ofcarbonate collection and removal of salts
bull Immobilization of the resultant oxide product and spentelectrolyte (after repeated use)
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
UNF
2wwwrosatomru
INTERACTION OF TERMAL AND FAST REACTORrsquoS FUEL CYCLES
Thermal reactors Fast Reactors
Model of RUSSIANIntegrated UNF Management System for 2025-2030
RBMK7 units
VVER-10001200
30 units(in Russia)
U fuel fab HLW Disposal
Fast Reactor FuelsReprocessing amp Fab
600 t
400 t
MOX-VVER Pu + U
Centralized UNF Storage(up to 30 000 MT HM)
RT-2 LWR UNFReprocessing plant
1000-1700 t of UNFyear
amp MOX Fab
UNF
UNF 250 t
UNF FR (W-Pu)
U-Pu-fuel
UNF
BN-800
BN-1200andor BREST-
1200
Several units
VVER-10001200
20 units(abroad)
U
UNF FR
Dimitrovgrad dry Process (DDP) MOXMOX flow sheet
Cathode(pyrographite)
Stirrer
UO22+
+
Pu4+
UO22+
UO2 PuO2
Cl2 Cl2+O2+ArStirrerCathode
Na3PO4
Fuel chlorination650 оС
pyrographite bathNaCl -2CsCl
Electrolysis-additional 630 оС
Melt purification650 оС
Cl-
(MAREE)RW4
MAREE
UO22+
UO2 +NpO2
Ar (Cl2)
+
Preliminaryelectrolysis
630 оС
NpO2+
UO22+
MOX
Cl2+O2+Ar
+
Main MOXelectrolysis
630 оС
PuO2+
PuO2+
MOX
4
Integrated flow sheet of spent MOX-fuel reprocessing
Freezing ofchlorine
Chlorination Electrolysis of therecovered melt
Precipitativecrystallization
Electrolysis of theoxidized melt
Melt purificationwith phosphate
Removal of captured salts
Cleaning of sublima
Excesschlorine
Off gases
UO2-1 PuO2 UO2-2 Phosphateprecipitate
UO2-1 PuO2 forfabrication of
fuel rods
UO2-2 Phosphateprecipitate
STORAGE STORAGE STORAGE
Spentelectrolyte
Solutions
Concentration of
solutions by
evaporation
Disposal Immobilizationon glass and
ceramics surfaces
Cl2
Off gas
Cl2 absorptionRemoval of
aerosols
Cl2
Off gas
Resultant solution goesinto radioactive drain
Salts
Water
Contaminatedvacuum cleaning
through filters
Gases to the airduct system
Offgases
Sublimates
Cl2
Off Gases
Incineration ofpyrographite
ashes
FuelMechanicaldecladding
Fuel rods
Treatment inthe resin
Decontamination
Disposal
Pyrographitecomponents
Units ofequipment
Metalequipmen
t
Solution
Burnable waste
Resultantsolution goes
into radioactivedrain
Resin
5
Summary of the MOX-fuel reprocessing process andmain types of radioactive waste
The MOX-fuel to be reprocessed is subjected to mechanical decladdinggrinding to a powder and loaded into the head device- chlorator - electrolyserAll the operations of pyroelectrochemical reprocessing are carried out in thedevice The sequence of operations is as follows
Fuel chlorination in molten NaCl-KCl LiCl-NaCl-KCl-СsCl
Electrolysis for removal of UO2-1 with some fission products (FPs)captured by cathodic deposit
Precipitative crystallization of PuO2 decontaminated from FPs and otherimpurities
Additional electrolysis for removal of UO2-2 with deposited FPs and otherimpurities
Molten salt purification by introduction of phosphates into the melt
6
01M HNO3
(3Li-2K)Cl+CdCl2+PuCl3
Fissile material
Fuelregeneration
Cd
Removal of salts
U+Pu+Cd+(3Li-2K)Cl
Partitioning of minoractinides and FP
(3L
i-2
K)C
l+М
А+
ПД
Removal of salts
Bi+МА+(3Li-2K)Cl
Fabrication of targets
Carbonateprecipitation
(3Li-2K)Cl+FP
Na2СO3
Immobilization
Precipitatecollection
(3Li-2K)ClAfter 3 cycles
Precipitatepurification
Condensation ofsolutions by evaporations
Concentration ofsolutions byevaporation
Aqueous solution(3Li-2K)Cl
Precipitate with FP
FP oxides
(3L
i-2
K)C
l
HNO3 dilute solution
Aqueous solution (3Li-2K)Cl
wa
ter
Condensation ofsolutions byevaporations
Aqueous solution (3Li-2K)Cl
(3Li-2K)Cl
РH
NO
3d
ilu
teso
luti
on
Cd sublimationand condensation
U+Pu+Cd
01M HNO3
(3Li-2K)Cl
UP
up
ow
der
Fuel fabrication
UPu
МА
+B
i
ре
ген
ер
Cd
Bi
(3Li-2K)Cl
water
Integrated flowsheet of pyrochemicalreprocessing of dense fuel
7
Summary of the so called ldquodenserdquo SNF (nitride metal) reprocessingprocess and main types of radioactive waste
The basic processes include the following stages of the dense SNFreprocessing
bull Anodic dissolution with cadmium cathode in molten 3LiCl-2KCl
bull Evaporation of liquid cadmium followed by separation fissilematerials for further manufacturing of metallic and nitride fuel
bull MA partitioning from fission products in a liquid metallic cathode
bull Precipitation of REE by Li2O+K2O trough introduction ofcarbonate collection and removal of salts
bull Immobilization of the resultant oxide product and spentelectrolyte (after repeated use)
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
Dimitrovgrad dry Process (DDP) MOXMOX flow sheet
Cathode(pyrographite)
Stirrer
UO22+
+
Pu4+
UO22+
UO2 PuO2
Cl2 Cl2+O2+ArStirrerCathode
Na3PO4
Fuel chlorination650 оС
pyrographite bathNaCl -2CsCl
Electrolysis-additional 630 оС
Melt purification650 оС
Cl-
(MAREE)RW4
MAREE
UO22+
UO2 +NpO2
Ar (Cl2)
+
Preliminaryelectrolysis
630 оС
NpO2+
UO22+
MOX
Cl2+O2+Ar
+
Main MOXelectrolysis
630 оС
PuO2+
PuO2+
MOX
4
Integrated flow sheet of spent MOX-fuel reprocessing
Freezing ofchlorine
Chlorination Electrolysis of therecovered melt
Precipitativecrystallization
Electrolysis of theoxidized melt
Melt purificationwith phosphate
Removal of captured salts
Cleaning of sublima
Excesschlorine
Off gases
UO2-1 PuO2 UO2-2 Phosphateprecipitate
UO2-1 PuO2 forfabrication of
fuel rods
UO2-2 Phosphateprecipitate
STORAGE STORAGE STORAGE
Spentelectrolyte
Solutions
Concentration of
solutions by
evaporation
Disposal Immobilizationon glass and
ceramics surfaces
Cl2
Off gas
Cl2 absorptionRemoval of
aerosols
Cl2
Off gas
Resultant solution goesinto radioactive drain
Salts
Water
Contaminatedvacuum cleaning
through filters
Gases to the airduct system
Offgases
Sublimates
Cl2
Off Gases
Incineration ofpyrographite
ashes
FuelMechanicaldecladding
Fuel rods
Treatment inthe resin
Decontamination
Disposal
Pyrographitecomponents
Units ofequipment
Metalequipmen
t
Solution
Burnable waste
Resultantsolution goes
into radioactivedrain
Resin
5
Summary of the MOX-fuel reprocessing process andmain types of radioactive waste
The MOX-fuel to be reprocessed is subjected to mechanical decladdinggrinding to a powder and loaded into the head device- chlorator - electrolyserAll the operations of pyroelectrochemical reprocessing are carried out in thedevice The sequence of operations is as follows
Fuel chlorination in molten NaCl-KCl LiCl-NaCl-KCl-СsCl
Electrolysis for removal of UO2-1 with some fission products (FPs)captured by cathodic deposit
Precipitative crystallization of PuO2 decontaminated from FPs and otherimpurities
Additional electrolysis for removal of UO2-2 with deposited FPs and otherimpurities
Molten salt purification by introduction of phosphates into the melt
6
01M HNO3
(3Li-2K)Cl+CdCl2+PuCl3
Fissile material
Fuelregeneration
Cd
Removal of salts
U+Pu+Cd+(3Li-2K)Cl
Partitioning of minoractinides and FP
(3L
i-2
K)C
l+М
А+
ПД
Removal of salts
Bi+МА+(3Li-2K)Cl
Fabrication of targets
Carbonateprecipitation
(3Li-2K)Cl+FP
Na2СO3
Immobilization
Precipitatecollection
(3Li-2K)ClAfter 3 cycles
Precipitatepurification
Condensation ofsolutions by evaporations
Concentration ofsolutions byevaporation
Aqueous solution(3Li-2K)Cl
Precipitate with FP
FP oxides
(3L
i-2
K)C
l
HNO3 dilute solution
Aqueous solution (3Li-2K)Cl
wa
ter
Condensation ofsolutions byevaporations
Aqueous solution (3Li-2K)Cl
(3Li-2K)Cl
РH
NO
3d
ilu
teso
luti
on
Cd sublimationand condensation
U+Pu+Cd
01M HNO3
(3Li-2K)Cl
UP
up
ow
der
Fuel fabrication
UPu
МА
+B
i
ре
ген
ер
Cd
Bi
(3Li-2K)Cl
water
Integrated flowsheet of pyrochemicalreprocessing of dense fuel
7
Summary of the so called ldquodenserdquo SNF (nitride metal) reprocessingprocess and main types of radioactive waste
The basic processes include the following stages of the dense SNFreprocessing
bull Anodic dissolution with cadmium cathode in molten 3LiCl-2KCl
bull Evaporation of liquid cadmium followed by separation fissilematerials for further manufacturing of metallic and nitride fuel
bull MA partitioning from fission products in a liquid metallic cathode
bull Precipitation of REE by Li2O+K2O trough introduction ofcarbonate collection and removal of salts
bull Immobilization of the resultant oxide product and spentelectrolyte (after repeated use)
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
4
Integrated flow sheet of spent MOX-fuel reprocessing
Freezing ofchlorine
Chlorination Electrolysis of therecovered melt
Precipitativecrystallization
Electrolysis of theoxidized melt
Melt purificationwith phosphate
Removal of captured salts
Cleaning of sublima
Excesschlorine
Off gases
UO2-1 PuO2 UO2-2 Phosphateprecipitate
UO2-1 PuO2 forfabrication of
fuel rods
UO2-2 Phosphateprecipitate
STORAGE STORAGE STORAGE
Spentelectrolyte
Solutions
Concentration of
solutions by
evaporation
Disposal Immobilizationon glass and
ceramics surfaces
Cl2
Off gas
Cl2 absorptionRemoval of
aerosols
Cl2
Off gas
Resultant solution goesinto radioactive drain
Salts
Water
Contaminatedvacuum cleaning
through filters
Gases to the airduct system
Offgases
Sublimates
Cl2
Off Gases
Incineration ofpyrographite
ashes
FuelMechanicaldecladding
Fuel rods
Treatment inthe resin
Decontamination
Disposal
Pyrographitecomponents
Units ofequipment
Metalequipmen
t
Solution
Burnable waste
Resultantsolution goes
into radioactivedrain
Resin
5
Summary of the MOX-fuel reprocessing process andmain types of radioactive waste
The MOX-fuel to be reprocessed is subjected to mechanical decladdinggrinding to a powder and loaded into the head device- chlorator - electrolyserAll the operations of pyroelectrochemical reprocessing are carried out in thedevice The sequence of operations is as follows
Fuel chlorination in molten NaCl-KCl LiCl-NaCl-KCl-СsCl
Electrolysis for removal of UO2-1 with some fission products (FPs)captured by cathodic deposit
Precipitative crystallization of PuO2 decontaminated from FPs and otherimpurities
Additional electrolysis for removal of UO2-2 with deposited FPs and otherimpurities
Molten salt purification by introduction of phosphates into the melt
6
01M HNO3
(3Li-2K)Cl+CdCl2+PuCl3
Fissile material
Fuelregeneration
Cd
Removal of salts
U+Pu+Cd+(3Li-2K)Cl
Partitioning of minoractinides and FP
(3L
i-2
K)C
l+М
А+
ПД
Removal of salts
Bi+МА+(3Li-2K)Cl
Fabrication of targets
Carbonateprecipitation
(3Li-2K)Cl+FP
Na2СO3
Immobilization
Precipitatecollection
(3Li-2K)ClAfter 3 cycles
Precipitatepurification
Condensation ofsolutions by evaporations
Concentration ofsolutions byevaporation
Aqueous solution(3Li-2K)Cl
Precipitate with FP
FP oxides
(3L
i-2
K)C
l
HNO3 dilute solution
Aqueous solution (3Li-2K)Cl
wa
ter
Condensation ofsolutions byevaporations
Aqueous solution (3Li-2K)Cl
(3Li-2K)Cl
РH
NO
3d
ilu
teso
luti
on
Cd sublimationand condensation
U+Pu+Cd
01M HNO3
(3Li-2K)Cl
UP
up
ow
der
Fuel fabrication
UPu
МА
+B
i
ре
ген
ер
Cd
Bi
(3Li-2K)Cl
water
Integrated flowsheet of pyrochemicalreprocessing of dense fuel
7
Summary of the so called ldquodenserdquo SNF (nitride metal) reprocessingprocess and main types of radioactive waste
The basic processes include the following stages of the dense SNFreprocessing
bull Anodic dissolution with cadmium cathode in molten 3LiCl-2KCl
bull Evaporation of liquid cadmium followed by separation fissilematerials for further manufacturing of metallic and nitride fuel
bull MA partitioning from fission products in a liquid metallic cathode
bull Precipitation of REE by Li2O+K2O trough introduction ofcarbonate collection and removal of salts
bull Immobilization of the resultant oxide product and spentelectrolyte (after repeated use)
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
5
Summary of the MOX-fuel reprocessing process andmain types of radioactive waste
The MOX-fuel to be reprocessed is subjected to mechanical decladdinggrinding to a powder and loaded into the head device- chlorator - electrolyserAll the operations of pyroelectrochemical reprocessing are carried out in thedevice The sequence of operations is as follows
Fuel chlorination in molten NaCl-KCl LiCl-NaCl-KCl-СsCl
Electrolysis for removal of UO2-1 with some fission products (FPs)captured by cathodic deposit
Precipitative crystallization of PuO2 decontaminated from FPs and otherimpurities
Additional electrolysis for removal of UO2-2 with deposited FPs and otherimpurities
Molten salt purification by introduction of phosphates into the melt
6
01M HNO3
(3Li-2K)Cl+CdCl2+PuCl3
Fissile material
Fuelregeneration
Cd
Removal of salts
U+Pu+Cd+(3Li-2K)Cl
Partitioning of minoractinides and FP
(3L
i-2
K)C
l+М
А+
ПД
Removal of salts
Bi+МА+(3Li-2K)Cl
Fabrication of targets
Carbonateprecipitation
(3Li-2K)Cl+FP
Na2СO3
Immobilization
Precipitatecollection
(3Li-2K)ClAfter 3 cycles
Precipitatepurification
Condensation ofsolutions by evaporations
Concentration ofsolutions byevaporation
Aqueous solution(3Li-2K)Cl
Precipitate with FP
FP oxides
(3L
i-2
K)C
l
HNO3 dilute solution
Aqueous solution (3Li-2K)Cl
wa
ter
Condensation ofsolutions byevaporations
Aqueous solution (3Li-2K)Cl
(3Li-2K)Cl
РH
NO
3d
ilu
teso
luti
on
Cd sublimationand condensation
U+Pu+Cd
01M HNO3
(3Li-2K)Cl
UP
up
ow
der
Fuel fabrication
UPu
МА
+B
i
ре
ген
ер
Cd
Bi
(3Li-2K)Cl
water
Integrated flowsheet of pyrochemicalreprocessing of dense fuel
7
Summary of the so called ldquodenserdquo SNF (nitride metal) reprocessingprocess and main types of radioactive waste
The basic processes include the following stages of the dense SNFreprocessing
bull Anodic dissolution with cadmium cathode in molten 3LiCl-2KCl
bull Evaporation of liquid cadmium followed by separation fissilematerials for further manufacturing of metallic and nitride fuel
bull MA partitioning from fission products in a liquid metallic cathode
bull Precipitation of REE by Li2O+K2O trough introduction ofcarbonate collection and removal of salts
bull Immobilization of the resultant oxide product and spentelectrolyte (after repeated use)
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
6
01M HNO3
(3Li-2K)Cl+CdCl2+PuCl3
Fissile material
Fuelregeneration
Cd
Removal of salts
U+Pu+Cd+(3Li-2K)Cl
Partitioning of minoractinides and FP
(3L
i-2
K)C
l+М
А+
ПД
Removal of salts
Bi+МА+(3Li-2K)Cl
Fabrication of targets
Carbonateprecipitation
(3Li-2K)Cl+FP
Na2СO3
Immobilization
Precipitatecollection
(3Li-2K)ClAfter 3 cycles
Precipitatepurification
Condensation ofsolutions by evaporations
Concentration ofsolutions byevaporation
Aqueous solution(3Li-2K)Cl
Precipitate with FP
FP oxides
(3L
i-2
K)C
l
HNO3 dilute solution
Aqueous solution (3Li-2K)Cl
wa
ter
Condensation ofsolutions byevaporations
Aqueous solution (3Li-2K)Cl
(3Li-2K)Cl
РH
NO
3d
ilu
teso
luti
on
Cd sublimationand condensation
U+Pu+Cd
01M HNO3
(3Li-2K)Cl
UP
up
ow
der
Fuel fabrication
UPu
МА
+B
i
ре
ген
ер
Cd
Bi
(3Li-2K)Cl
water
Integrated flowsheet of pyrochemicalreprocessing of dense fuel
7
Summary of the so called ldquodenserdquo SNF (nitride metal) reprocessingprocess and main types of radioactive waste
The basic processes include the following stages of the dense SNFreprocessing
bull Anodic dissolution with cadmium cathode in molten 3LiCl-2KCl
bull Evaporation of liquid cadmium followed by separation fissilematerials for further manufacturing of metallic and nitride fuel
bull MA partitioning from fission products in a liquid metallic cathode
bull Precipitation of REE by Li2O+K2O trough introduction ofcarbonate collection and removal of salts
bull Immobilization of the resultant oxide product and spentelectrolyte (after repeated use)
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
7
Summary of the so called ldquodenserdquo SNF (nitride metal) reprocessingprocess and main types of radioactive waste
The basic processes include the following stages of the dense SNFreprocessing
bull Anodic dissolution with cadmium cathode in molten 3LiCl-2KCl
bull Evaporation of liquid cadmium followed by separation fissilematerials for further manufacturing of metallic and nitride fuel
bull MA partitioning from fission products in a liquid metallic cathode
bull Precipitation of REE by Li2O+K2O trough introduction ofcarbonate collection and removal of salts
bull Immobilization of the resultant oxide product and spentelectrolyte (after repeated use)
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
8
DDP Pyro HLW
HLW typePhosphate or oxide
concentrateSpent
electrolyteTechnological
wastesPyrographite
OriginProduct s after
purification
of molten salt
Spent Salts
afteraccumulation
of Cs and Sr
Fuel pin
claddings
metallic
equipment
Cruciblestructuralmaterials
Characteristics
Crystalline fine powdercontaining
REE and MA
Alkaline metalschlorides
Metallic wastesCombustible
wastes
Treatmentprocedures
Intermediate storage
Vitrification orCeramization
Intermediatestorage
Vitrification orCeramization
Compactification
Disposal
GrindingFlamelessburning
Recycling of
Ash into
head ofreprocessing
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
DDP Pyro Wastes treatment
Salt residueSalt
purificationPyroreprocessing
Na3PO4
Phosphates
Fission products
Radioactive Cs
NaClCsClNdPO4C
ePO4
Waste Phosphates Salt residue
Special features contain fission productsAlkaline metal chlorideshigh activity significant
heat release
Basic elements11 wt Nd
44 wt Ce
8196 wt CsCl
1804 wt NaCl
Quantitylt015 kgkg of fastreactor SNF
lt003 kgkg of fastreactor SNF
Data by TOSHIBA estimation for DDP
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
10
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
As a result of the BOR-60 fuel reprocessing (an ultra high burn-up of 21-24 ha)
phosphate precipitate was obtained
Weight g Bulk densitygcm3
Specific heatrelease Wkg
Specific radioactivity Cig
α-nuclides γ-nuclides
442 06-07 95 93middot10-2 10
Some characteristics of phosphate precipitate
106Ru+106Rh 17middot107 154Eu 78middot108 241Am 32middot109(925)
144Ce+144Pr 33middot1010(90) 155Eu 03middot1010(9) 242Cm 63middot107
137Cs 16middot107 54Mn 48middot106 244Cm 21middot108
125Sb 13middot107 60Co 1middot106
Radioactivity of nuclides in phosphate precipitate Bqg ()
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
11
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Phosphate precipitates
Hydrolysis tests on phosphate precipitate revealed that the 134Cs and 137Cs isotopesmake for 55 to 88 of the solution activity
the 144Ce (Pr) isotopes make for 68 to 21 of activity and 125Sb produces from 45to 16 of activity (see Table )
NuclidesDuration of hydrolysis tests days
1 3 7 28 100
137Cs 22 10 07 02 006
144Ce(Pr) 39middot10-4 16middot10-4 8middot10-5 47middot10-5 35middot10-5
125Sb 01 007 007 003 002
Total of γ-nuclides
53middot10-3 23middot10-3 17middot10-3 53middot10-4 21middot10-4
Total of α-nuclides
29middot10-4 72middot10-5 55middot10-5 25middot10-5 21middot10-5
Release rates of nuclides from phosphate precipitate( as to the nuclide activity in the sample distilled water 20ordmС)
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
12
In Dec 2010 26 g of oxide concentrate were obtained as a result of dense fuelreprocessing
Precipitateweight g
Content of some components and radionuclides
Pumass
241AmBqg
137Сs Bqg
154EuBqg
144CeBqg
26 lt0001 54middot106 31middot104 10middot107 86middot106
HIGH LEVEL WASTE FROM PYROCHEMICALPROCESSES AND THEIR SPECIFICATION
Oxide precipitate
Characteristics of real oxide precipitate
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
13
As an example we refer to the spent electrolyte generated after high burnup fuelreprocessing of the BOR-60 reactor (1995)As a result of reprocessing 81 kg of molten alkali chlorides remainedTheir original composition was LiCl-453NaCl-488KCl-066CsCl
HIGH LEVEL WASTE FROM PYROCHEMICAL PROCESSESAND THEIR SPECIFICATION
Spent electrolytes
Uweight
Puweight
Activity ofα-nuclides
GBqkg
Activity of γ-nuclides GBqkg
106Ru(Rh)
125Sb 134Cs 137Cs144Ce(Pr)
147Pm154E
u60Co
lt0001 lt0001 02 19 07 1517 2024 200 333 59 01
Chemical and radionuclide composition of spent electrolyte
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
Characteristic
HLW type
Phosphateprecipitate
Spent saltelectrolyte
Phosphate precipitate+ spent salt electrolyte
Glass matrix typePb(PO3)2
NaPO3
NaPO3 AlF3
Al2O3
NaPO3 AlF3
Al2O3
Introduction methodvitrificationТ=9500С
vitrification withoutchloride
conversionТ=9500С
vitrification withoutchloride conversion
Т=9500С
Introduced waste amount 28 20 36
137Cs leaching rate as of the 7th
day gcm2 day710-6 710-6 410-6
Thermal resistance 0С 400 400 400
Radiation resistance 107 Gr (for and ) 1018 -decayg
Vitrification of HLW from DDP pyro reprocessing
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
15
Vitrification of HLW after pyrochemical processes
Vitrification of phosphate precipitates
A possibility is shown to embed the phosphate precipitate in the alumofluophosphate glass
The real phosphate precipitate generated after BOR-60 fuel reprocessing contains 223of REE and 147 of iron 96 of activity is given by 144Ce (Pr) while 86 of alpha-activity is given by 241AmA composition of glass matrix and waste was selected to carry out a real experiment(NaPO3-75 AlF3-10 NaF-5 Al2O3-10)-85 phosphate precipitation - 15
At the vitrification stage (T=1000C) the release of activity into the gas phase made up28∙10-3 and 10∙10-4 of the initial phosphate precipitate activity for - and -emittersrespectively Among the -emitters 125Sb (516 ) and 137Cs (419 ) made the keycontribution to the gas phase activity as for the -emitters it was 241Am (92 ) Thermalconductivity of the vitrified waste made up 08-11W(m∙0С) at 35-300C that was anadmissible level for the phosphate glass [10 11]
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
16
Nuclides
Test duration
3rd
day7th
day14th day
21st
day28th
day58th
day88th
day118th day
Al 21∙10-6 22∙10-6 15∙10-6 23∙10-7 24∙10-7 27∙10-7 10∙10-7 89∙10-8
Na 12∙10-5 74∙10-6 72∙10-6 63∙10-6 45∙10-6 34∙10-6 11∙10-6 52∙10-7
P 30∙10-6 29∙10-6 84∙10-7 32∙10-7 35∙10-7 51∙10-7 27∙10-7 16∙10-7
F 70 ∙10-6 69∙10-6 51∙10-6 43∙10-6 24∙10-6 15∙10-6 79∙10-7 77∙10-7
125Sb 69∙10-6 24∙10 -6 13∙10-6 81∙10-7 74∙10-7 24∙10-7 24∙10-7 22∙10-7
137Cs 22∙10-5 97∙10-6 56∙10-6 39∙10-6 28∙10-6 27∙10-6 16∙10-6 9∙10-7
144Ce(144Pr) 12∙10-6 12∙10-6 41∙10-7 36∙10-7 23∙10-7 64∙10-8 38∙10-8 24∙10-8
154155Eu 16∙10-6 18∙10-6 63∙10-7 50∙10-7 46∙10-7 13∙10-7 78∙10-8 48∙10-8
241Am 11∙10-6 87∙10-7 66∙10-7 49∙10-7 33∙10-7 88∙10-8 59∙10-8 39∙10-8
242244Cm 12∙10-6 85∙10-7 67∙10-7 50∙10-7 34∙10-7 93∙10-8 65∙10-8 44∙10-8
Rate of components leaching from radioactive glass sample P-1with phosphate precipitate at Т=20-25С g(cm2day)
Vitrification of HLW after pyrochemical processesvitrification of phosphate precipitates
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
17
Sample No NaPO3 AlF3 Al2O3 BeO 3LiCl-2KCl 3LiPO3-KPO3
M ndash 1M ndash 2M ndash 3M - 4R ndash 1R - 2
6751010
67567510
1711717181817
--3
45453
543----
10--
1010-
-7070--
70
Content of glass charge mixture wt
Characteristics of samples
Parameter M-1 M-2 M-3 M-4 R-1 R-2
Weight gDiameter mmSurface sm2
Density g sm3
Radioactivity Bk g
392313364238
-
398309359246
-
329731053269242
-
331307
3273241
-
29130731223271∙106
47593139425224∙107
Immobilization of spent electrolyte by vitrification (2010)
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
18
Simulating samples М-4 (а) М-5 (б) М-6 (в) М-7 (г)
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
19
Sample ComponentTest duration days
3 7 14 21 28 58 88 118
М - 4
М - 5
Р ndash 2
NaAlPF
NaAlPF
NaAlPF
137Cs
1910-5
3310-6
2310-6
1810-6
8010-6
4810-6
2510-6
1810-6
1310-5
1710-5
8310-7
1010-5
1210-5
1210-5
7810-7
1110-6
1510-6
5510-6
1110-6
1210-6
9110-7
4210-6
2510-6
7110-7
4210-6
1510-6
6210-6
5310-7
7010-7
1110-6
4410-6
9410-7
8510-6
6310-7
1510-6
5610-7
6310-7
3910-6
1510-6
5510-6
3010-7
2610-7
5110-7
3210-6
6910-7
3610-7
5210-7
8310-7
3210-7
5010-7
2910-6
8610-7
1810-6
2610-7
1710-7
4010-7
2710-6
3410-7
2610-7
4510-7
7710-7
2810-7
6210-8
2410-6
8110-7
2510-7
4310-8
5510-8
1210-7
8610-7
3710-8
4910-8
1210-7
5210-7
2110-7
5010-8
9610-7
5010-7
2510-7
3610-8
4610-8
9410-8
5210-7
3610-8
4910-8
4810-8
4210-7
1010-7
5510-8
96104610-7
2410-7
3310-8
4010-8
9410-8
5010-7
3610-8
4310-8
4910-8
4210-7
7910-8
5310-8
4110-7
4210-7
Rate of glass components leaching from samplesat 20-25C g(cm2day) (chlorides conversion)
Vitrification of HLW after pyrochemical processesVitrification of spent electrolytes
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
Characteristics
Type of high-level wastes
Phosphate concentrate Spent salt electrolyte
Type of ceramics monazite Cosnarite (NZP)
Method of introduction into ceramicspressing calcination
Т=8500С
Conversion to NZP from themelt or aqueous solutionpressing calcination
Т=10000С
Quantity of waste introduced intoceramics
100 3040
Leaching rate of 137Cs on 7-th daygcm2 day
110-6 310-6
Thermal stability 0С 850 1000
Radiation resistance 5108 Gy( for and ) 1019 - decayg
Ceramization of HLW from DDP pyro reprocessing
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
21
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
ElementMass
fraction
La 274 Gd 01 Ti 019 Pb 014
Ce 411 Y 041 Mo 055 Ca 274
Pr 206 Al 020 Cu 014 Sr 280
Nd 1027 Cr 203 Mn 027 P+O 5417
Sm 137 Fe 1370 Zn 021
Eu 020 Ni 055 Mg 102
A simulator of phosphate concentrate of pyroelectrochemical processis produced from NaCl-2CsCl melt
The produced powder was compacted into pellets annealed in air at 800-1400 0С for 10-12 hours Phase composition of products was analyzed by X-rayingChemical composition was identified by the emission spectrum analysis and X-ray spectrummicroanalysis with the use of a scanning electronic microscope (SEM) The ceramicsincluded the main monazite-like phase with the lattice parameters ofa=6773plusmn0003 Aring b=6987plusmn0002 Aring c=6435plusmn0002 Aring β = 10368plusmn002 degrees
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
22
Ceramization of HLW after pyrochemical processesCeramization of phosphate precipitates
The SEM results showed the presence of three phases in its composition light greygrey and dark grey Mass fractions of cations together with the X-ray diffraction analysisdata are evident of the following1 light grey dominant phase monazite incorporating lanthanides2 dark grey phase ferrous orthophosphate FePO4 with isomorphic impurities - Al Cr3 grey phase Fe- and Cr-based oxide (Fe Cr)2O3 with the hematite structure
Images of microanalysis regions for ceramics on the basis of phosphateprecipitate light grey (а) dark grey (b) and grey (c) phases
10 microm 10 microm20microm cbа
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
23
Ceramization of oxide cocentate into Murataite type ldquofuserdquo ceramics(YNa)6 Zn(ZnFe3+)4(TiNbNa)12O29(OFOH)10F4
OxideComponents mass
Composition 1 Composition 2
Charge components
TiO2 55 55
MnO2 10 10
CaO 10 10
Al2O3 5 5
Fe2O3 5 5
ZrO2 5 5
HLW simulators (or real oxide presipitate) 10 mass
SrO 03934 00426
MoO3 21930 02376
CeO2 27222 18680
Pr6O11 25452 02758
Nd2O3 05042 00546
Sm2O3 07812 00846
Eu2O3 05265 00570
UO2 03344 73800
100000 100000
M
M
M
M MP
M M M
M
M
M
MM
M
M MMF
M
M
0
20
40
60
80
100
120
20 30 40 50 60 70
2Q degree
I
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
24
Ceramization of HLW after pyrochemical processes
Ceramization of spent electolytesNZP (kosnarite)- structure
Calculatedcomposition
Na05K05Zr2(PO4)3 Na13Cs23Zr2(PO4)3 (Li0090Na0409K0441Cs0060)Zr2(PO4)3
Synthesismethod
Impregnation withН3PO4 solution
Precipitation fromsolution
Precipitation from solution
Annealing 1000 0С 3 h 1200 0С 5 h 1000 0С4 h
Latticeparameters of
the NZPphases
a = 8737(4) Aringc = 2371(2) AringV = 1567(3) Aring 3
a = 8607(3) Aringc = 2471(2) AringV = 1585(2) Aring 3
a = 8746(1) Aringс = 2354(1) AringV = 1559(1) Aring 3
SEM-images of ceramic particles with the composition Na13Cs23Zr2(PO4)3а) light phase b) dark phase c) grey phase
20 microm50 microm 50 micromа b c
(M1)[6](M2)3[8][(L)2
[6](P[4]O4)3]
М1 М2
LO6
(M1)
PO4
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
25
Ceramization of spent electolytes - Langbeinite structureс
аb
PO4
PrO6
ZrO6
atoms К
Initial electrolyte Total composition of phosphate
NaCl-KCl NaKFeZr(PO4)3
NaCl-2CsCl Na066Cs133FeZr(PO4)3
LiCl-453NaCl-488KCl-066CsCl Li018Na082K088Cs012FeZr(PO4)3
NaCl-2CsCl Na066Cs133CrZr(PO4)3
3LiCl-2KCl+ NaCl-2CsCl Li06K04Na033Cs067FeZr(PO4)3
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
26
Ceramization of spent electolytes - Langbeinite structure
ElementMass fraction(calculation)
Mass fraction(experiment)
light grey phase
Mass fraction(experiment)
dark grey phase
Na 245 206 359
Cs 2837 2952 2113
Fe 894 704 687
Zr 1461 1647 2019
P 1487 1463 1608
O 3074 3016 3214
а
b
SEM images of ceramic particles Na066Cs133FeZr(PO4)3a-light grey phase b- dark grey phase
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
27
Ceramization of spent electolytesLangbeinite structure
ElementLeachingperioddays
Leaching rate g(сm2middotday)
Na066Cs133FeZr (PO4)3
NaKFeZr(PO4)3
Li018Na082K018Cs012
FeZr(PO4)3
Na066Cs133FeZr(PO4)3
with bindingBi2O3+NaF
Na37
gt1110-4
9810-6
2310-4
1010-4
2910-6
1710-6
Cs37
gt1110-3
5910-4
2310-4
1010-4
14middot10-5
lt64middot10-6
Fe37
3510-5
4810-6
3110-5
1510-5
3110-5
1710-5
63middot10-6
37middot10-6
Zr37
6610-7
9910-7
1610-6
5110-7
1010-6
1810-7
lt7210-7
lt6110-7
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
28
bull Pyro processes are characterized by a small spectrumand volume of the produced wastes their high specificactivity absence of liquid high-level process wastes
bull The main types of solid process wastes are phosphateand oxide precipitates as well as spent electrolytes
bull The main waste forms of pyrochemical processes can bestored long-term in shielding containers without usingany schemes of their chemical conversion andimmobilization
bull If necessary to enhance efficiency of the HLW shieldingbarrier for their long-term geological disposal wasteforms of pyroprocesses can be converted into morestable chemical forms
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions
29
bull Alumofluophosphate glass and monazite-based matrixcan be used for immobilization of phosphate precipitates
bull Fuse ceramics on the basis of murataite mineral can beused for immobilization of oxide precipitates
bull Alumofluophosphate glass and ceramics with thestructures of kosnarite and langbeinite can be used forimmobilization of salt electrolytes
bull Further investigations on immobilization of salt systemscan be aimed at a search of effective ways to prevent theformation of conversion and corrosion chlorine-containing gases effective chemical bonding of chlorine-ion research and development of hybrid glass-ceramicmethod of spent electrolytes fixation
bull (YNa)6 Zn(ZnFe 3+)4(TiNbNa)12O29(OFOH)10F4
Conclusions