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3. Liquid RW: 0-10% solids, slurryBasic principles*: volume + cost reduction, minimisegeneration, reduce volume, optimise treatment +conditioningTreatment: transfer, concentration, transformation; entiresystem, optionsForms: decontamination + regenerative solutions,contaminated + scintillation fluids, condensates, drains,laundry, evaporator bottoms..Sources: mines, reactors, reprocessing, ..Reactors: low + high purity RW, chemical, detergents,miscellaneous, primary + secondary (PWR)Reprocessing: 5 m3/t HLW, tanks, 60 m3/t MLWInstitutions: scintillation, H-3, C-14Wet waste: 10 - 99% solids, collection, pretreatment,dewatering, solidificationcollection: 60 days, decay, surge capacitypretreatment: remote handlingdewatering: decantation, filtration, centrifugation, 25%cementWW technologies: disposal <I% free water, absorption(organic and inorganic sorbents), sludge handling: filtrationcake 84%, centrifuging, freezing + thawing no RI releaseManagement of LRW in NPP: regulatory limits NRCprocessing systems: filtration (F), ion exchange (IE),evaporation (E), condensate polishing (CP)High purity: F + IE + recycle, Low purity: <0.01 mho/m: F
Iodine100100100
All*100001001000
+ IE, >0.01 mho/m: E + CP by IE. Chemical: E + ? CP byIE. Detergent: F. Miscellaneous: E + CP. Secondarysystem: F + IEVolume reduction: disposal + transportation costDrying: injection fluidized bed 300-500 C, 190 l/h,conveyor, hopper, off-gas: gas/solid separator + venturiscrubber + REPA + C. Drying and incineration: ionexchange resins, off-gas: zeolites-AgCrystallization*: 120 l/min, 50% saltEvaporation: >0.01 mho/m, different compositionsEvaporator = heater + body + deentrainment device +condenser + pumpsTypes**: natural/forced circulation, heater: external/internalhorizontal/vertical, thin filmDecontamination factors (feed/distillate) used by NRC forevaporators.Type ofwasteNo Detergent WasteDetergent Waste IncludedBoric Acid* except iodineSeparation factors (bottom!distillate) :100 k - 1 M fornonvolatilesIon exchange*: <0.01 mho/m, polymers, styrenedivinylbenzene, fonns: R+, OR-
•harac ens ICS 0 lOn-exc ange resms:
Type FG R RL- C-eq/l pH MO% T-F
SA S H2SO4 95 1.5-2 1-14 250
SB QAl NaOH 80 0.5-1 1-14 140
SB QA2 NaOH 80 0.5-1 1-14 100
WE amme NH40 95 1.5- 1-7 200s H 2.5
Ch t·r f"
SA = Strong acid, SB = Strong base, WE = Weak base, FG= Functional Groups (8 = Sulfonic, QA = Quaternaryammonium (types 1 or 2», R = Regenerant, RL =Regeneration level, C = Capacity, MOT = Maximumoperating temperature.Properties: strong exchanger: + efficiency (dissociation ofsalts), - regeneration; weak exchanger: slow, $, shorter life,pH +. T sensitive; nuclear grade leachable impurities,uniform size; selectivity, particle size: 0.4 - 0.7 mm, flowrate 1 - 40 l/s/m2
, pressure drop 0.1 - 2 kg/cm2, swelling
Mixed vs separate bed: regeneration, separation, mixing
CS,Rb2
Decontamination factors «0.1 mCi/l):System Cations AnionsMixed Bed (Li3BO)) 10 10Mixed Bed (H+OH-):Powdex (Any System) 10(10)* 10(10) 2(10)Radwaste 100(10) 100(10) 2(10)Cation Bed 100(10) 1(1) 10(10)Anion Bed 1(1) 100(10) 1(1)Filtration: cake + filtrate, septum (membrane)Types: PWR: disposable (cartridge*) BWR: precoat*,metallic: sintered metal (5 flm) or wire mesh (8 flm),clogging backflushing cleaningprecoat F: diatomaceous earth, efficiencyflatbed F: belt, screen, e = 95% (> 1 flm), oilcentrifugal F*: horizontal filter discs,P< 4.2 kg/cm2
, spin, e> 95% (> 1 flm), Europeetched disk F: pressure vessel, 5.3 kg/cm2
, backflushing with .compressed ait - slurry to evaporator, e = 100% (> 5 flm),no precoat - waste volumeReverse osmosis: osmotic pressure*, membranes : celluloseacetate, compaction, hydrolysis, fouling;types*: spiral wound, hollow-fibre (aromatic polyimide, D= 100 flm, walls: 25flm, 42 kg/cm2 ph 2-14), tubular(external/internal 100/40 kg/cm2
)
Ultrafiltration: colloids. Centrifugation*: basket/helical,plugging. System design: tankage, flexibility, sampling,maintenance, operator exposure
Tanks: bottoms, man way opening 60 cm, shielding, steel,SS, fibreglass; Evaporators: segregated + shieldedcomponents; Resin handling, operation: planning,redundancy, cross-connections, trainingSolidification of HLW*: aims: monolith, resistance,leaching, $;Vitrification in France*: 1958, 1963: 15 kg glass blocks1000 Ci/l, pot technique 1969-73 induction heating 1180 CMarcoule 12 t ofglass 3000 Ci/l OF = 1E+6 liquids 1E+11gas; continuous process: flexible, $, 1972 calciner 300 Cglass frit; La Haque 800 m3/y glass 100 W/IVitrification in US: PNL, 1150 C, off-gas C-14 Ru 1-129removed, canisters air-cooled vaults, storage tanks*, in situvitrification*: PNL, 3.5 MWobsidianSolidification of MLW: LLW regulations, free liquid .detection: process control (boundary conditions), detection(inspection)Cement: silicates of Ca,AI,Fe oxides, + lime, magnesia,gypsum - swelling + setting; 25% water, boric acid, 5-10%waste solids; mechanical strength: >15% waste, resins,sludge; +: $ well known available self-shielding no vapoursshelflife strength leachability mixing: in-container/on-line;-: pH sensitive swelling cracking volume dust prematuresettingUrea-formaldehyde*: ~60% solids catalyst(H3P04,NaHS04) polymerization 1 -30 min, curing hours, cross-linking evaporator concentrate/UF = 1 - 3, free
P G GF RE GGREGP P FP P FF G FG G* G0.5 0.6-1 >2ML ML ML1.5-2 1-1.3 1-1.5G F WESeldom 0 Never
water release, sludge, resins, Na2S04, paper pulp/woodflourOther polymers: thermoplastics, PE, Vinyl ester styreneAsphalt*: organics, asphaltenes, malthenes, Europe, heating150 C, mixing: thin film evaporator extruder/evaporator*, +:well known, available, compatible, $, no free-standingwater, individual coating, shelf life, leachability, not achemical process; -: flammable, fires, salts, gas formation,melting, mixing, vapoursComparison of cement, urea formaldehyde resin and asphaltComparison Factor Cement Resin AsphaltShelf life of immobilizing agent Long Short LongMix fluidity P G FMixer cleanability P G FChemical tolerances for:Boric acid solutionN~S04 solutionAlkaline solutionDetergent waste solutionOrganic liquidsIon exchange resinsSludge
Volumetric efficiency$Product formProduct density, g/cm3
Water binding strengthResidual free water
Comparison Factor Cement Resin AsphaltMechanical strength G F GProduct stability G LW GCombustibility No Yes YesFreeze/thaw resistance F P GLeach resistance M M HighRE = Reduced efficiency, * = may require pH adjustment,$ = Defmed as the ratio ofthe volume ofradwaste treated tothe volume of fmal product. G = Good, P = Poor, F = Fair,M = Moderate, WE = Water evaporation duringpreparations, LW = loses water, ML = Monolith, 0 =OccasionallyManagement of HLW in the US: reprocessing, nuclearweapons, submarines, underground tanks*: Hanford singlewalled 1960 leaks 2000 m3
, Savannah RiverManagement of LLW: segregation by T and formMethods: aqueous: T< 90 d decay + drain, T> 90 d burial;organic: incineration 12% burial 88%.Disposal of LLW: doses to public DEL, operating targetsALARA«DELGround D: US (Hanford, ORNL, SRP) 1.3E+8 m3
, 2.5E+6Ci discharged, soil stratigraphy, texture, ion exchange,monitoring wells, Ru-l06 370 m in 8 y, nitrates 520 m in 8y; salt mines, porous sandstonesSea D: volume, not a drinking water, discharge point,horizontal jet, eddy diffusionReconcentration: absorption adsorption, sea bed
JJ.?Concentration factors , Derived Working Limits (D-nCi/l)for seawater, ICRP Pennissible Daily Intakes (PDI-Ci) andsafe release rates (R-Ci/y) for fish (F) and white mussel:WM) .
RI Fe-59 Zn-65 Cs- Sr-90 H-3 Pu-137 239
F 5300 5200 74 1 1 5
WM 27000 13000 14 1 1 290
D 48 140 2400 880 26E+6 380
R 150 450 7500 2800 8E+7 1200
PDI 130 220 44 0.22 6600 11Environmental surveys: extemaVintemal exposurePreliminary discharge: sampling, RI concentrationsDisposal in rivers: dry weather flow, drinking water
liquidwaste
I
collectionsegregation
off-gastreatment
volume I/~======!.J
reductiontt« ..., ':ftWit pure
/ '" lI~~t~!'rr------{
transportinterimstorage
disposal
VACUUNSYSTEM
COOLINGWATER VENT
CONDENSER SUBCOOlER
ENTRAINMENTSEPARATOR
CRYSTALLIZER
~FEED
STEAMCONDENSATESTEAM
PRODUCTRECIRCULATION
PUMP
COOLINGWATER
TO TOFEED DISTILLATE FEEDTANK TANK
TODISTILLAlTANKS
6. LAYOUT OF A CRYSTALLIZER SYSTEM FOR VOLUME REDUCTION OF L1QIRADWASTE (COURTESY OF GILBERT/COMMONWEALTH COMPANIES' REA[PA., AND HPD CORPORATION, GLEN ELLYN, ILL.)
II0TOII OlllVE - __--
TO' , _..r::~~r-L-lII0TOll IEAIIING
SE'AllATOil
fEED!i'..:.,~~ VA' 011;0:,. OUTLET
HEATINGMEDIUM
"
"..:'
II0TOII •..•·"·,;
,,HUTING •
A Il T · I, ......
~ I•
.' ••;
,;
~ ,~
"
HEATINGMEDIUM
10TTOMlEAlIlNG
'110DUCT OUTLET-----=~~
CUTAWAY VIEW SHOWINGROTOR BLADES
VAPOR ..
DRIVE
VAPOR
iVENT
i
FEED
•DRIPS
LIQUID
STEAM
~•.,
+THICK
LIQUOR
" ., ,
~IG. 5. THIN-FILM EVAPORATOR (HORIZONTAL TYPE). ,---_._----------.....;-----------
FLASHCHAMBER
DEM/STER
<f-STF;AM(CONDENSING .OUTSIDE TUBES I
! I I!i ! !IiII' I I
., I I' . i. I
I. 1 II :I !:,' III', •• I
! ill! ,::,. !II I' I; ,'/. ! I I I
, 'I I' " ' ,:I I. . i I' I •I I I: I. .
IzQ-..4.J:;)Ua:-u
APPROXIMATELIQUID LEVEL-~
~_""' ...............,.,o.n..VENT+4-.~~ 'I I I i
I I" ~I IICUTAWAY VIEW OF I . .' I'SHELL'flNu'TUSE : 1,,;';;!l1 ~HEAT EXCHANGER .' '., .i .Ii, I I'LIOUOR BOILING , ! I II ' .:..INSIDE TUeES---t-~i !I'llil:
DRIPS ,-r- I. i: I
VAPOR
f
+THICI(LIQUOR
3. SHORT·TUBE VERTICAL (CALANDRIA OR STANDARD) EVAPORA'
,
. ...... '.' ..
.'. ..... ~..
..~THICK' LIQUOR
, .. . - . . ...
,M-- NATURAL CIRCULATIONOF UNVAPORIZED LIQUID
" VAPOR
'. ~.. t '.....
ENTRAINMENTSEPARATOR
14-- FLASH CHAMBER":--;.!,
r"~E:::::::~-t-:--IMPINGEMENT BA FFLE___ APPROXIMATE
LIQUID LEVEL
VE NT·.....~-·c:::::
, FEEO---'"
DRIPS ....1---'«:
STEAM--;.,...----....r::(CONDENSING OUTSIDE
TUBES)LIQUID BOILING INSIDE .
TUBES------l
"AWAY VIEW OF-tELL-ANO-TUBE::AT EXC HANGER
~ure 5-5 Natural-circulation~ iisin'g-film; long~tube verticai 'evaporator ~ith ~n 'inter-I heater. Source: (DOE 1984). ." ' ',.' .... ,:', .;" I,
------_.-' ...,. _...._-------
VAPOR
tDEMISTER
C:llo1l!t- FEEO
c:J.-. THICK LIQUOR
.J, .DRIPS ~..~=~~
z,- 7 \~~, ~ I \ ".~~. . , .I .~._~" I I', ~ l..-. •,1',' I -",I, - ! II
I, I I, lll~- FLASH CHAMBER
~-;---IMPINGEMENT BAFFlI,~, I' Ii
. . I APPROXIMATE.~! II I LIQUID LEVEL
STEAM 'i ~.:-\....\-r---.--:-~
LIQUOR BOILINGINSIDE TUBES
. ·CUTAWAY VIEW OFSHELL-AND-TUBEHEAT EXCHANGER
FIG, 7. FORCEO-CIRCULATION EVAPORATOR WITH AN EXTERNAL HORIZONTAL HEATER
----_... _--_ ..,----------------------
WATER OR WASTE SOLUTIONINLET
-'STRIBUTOR--
REGENERANTINLET ANDBACKWASHWATEROUTLET__+-__--.
WATER OR WASTE SOLUTIONINLET
DISTRIBUTOR --..,L'
INLET FORCAUSTICREGENERANT FeRANION EXCHANGERAND BACKWASHWATER OUTLET -i-----,
AIR VENT
DEIONIZEDSOLUTIONOUTLET AND9ACKWASHWATER INLET
(a) SEPARATE BED SYSTEM
SPENTREGENERANTEFFLUENTCOLLECTOR
AIR IN
(b) MIXED-BED
SEPARATRESINLAYERSREPRESECONDITtCREGENEI
DEIONIZED SOLUTICOUTLET AND ACIDREGENERANTINLE(AND BACKWASH WI
SYSTEM
FIG. 9. SCHEMATIC DIAGRAM OF MIXED·BED AND SEPARATE·BED ION EXCHANGE SYSTE
INLET-+--J
TYPICAL WOUND--oFILTEA ELEMENT(FLOW FAOM OUT-
SID E TO INSIDE)
OUTLET
HINGEDL.ID
SWINGBOLTS
---tttt==- BASKETLIFTING
RING
r--_ REMOVABLE BASKET(CONTAINING SEVERALFILTER ELEMENTS)
L.--PRESSUREVESSEL
~---+~I-+-GAS KETS
VESSELSUPPORT
Figure 5.3 Typical disposable cartridge filter illustrating liquid flow from outside;"~;~ .. "f ".l",ment. Source: (DOE 1984).
PRECOATING WITH ALTER AID THE FILTEIIING CYCLE 8ACKWAIHING
---:::m::Iim1_lID
-o • Q
• ••o•,
'. ",
FIG. 10. OPERATIONAL CYCLE OF A PRESSURE PRECOAT FILTER HAVING VERTICAL TUBULAR ELEMENTS
(From Croll·Reynold. brodlure on CaRita mlero)
-----------_._--_._------
-n£COUING
IfI
fILLING THE FtLTEll
4SCAVENGE FILTRATION
"
3FILTRATION
6
CElilBlFUGAl DISCHARGE ~~-l~ [~~!-
~= L2J'
FIG. 11. OPERATIONAL CYCLE OF A CENTRIFUGAL PRECOAT FILTER
(From Nuwco, Inc. brochure on Schenk filters.)
DILUTESOLUTION
.,' .
••., .•
CONCENTRATED
• SOLUTION ••
• • ••• •
• • • •· •• • •• • •• • • • • •
• • • • • • • •• • • •
• • • • -. IOSlloTlc• • •
PRESSURE• • • •• • • • •• • · • •• • • •• • • • SEMIPERMEABLE• • •• • • MEMBRANE•• •• • •
•
, .Figurc·14.1. ~ . .':. .' ." . -.' ..' . . . . ....-.' "... . - . ." .
Osmosis: normal flow from low to high concentration.. '. ", ~ ... ..' '. ....
./
.. '
PRESSURE
. .. .
DILUTESOLUTION
• •
. - ~ ,- .SEMIPERMEABLE
MEMBRANE'•
• ••
• •• •
• • •• ••
• ,• • •
I • • • •• • • • • • • • • •• • • • •• • •• • • • • •
CONCENTRATED''., SOLUTION.'
•
•••• •... .. ...• • • • • •
· . . " ., ... . . .. .• • • •
.,
igure 14.2 Reverse osmosis: flow reversed by application of pressure to high-conceltration solution.
IfIO,eoblt ' . .; .. ' ,:",tmbront .~;' ::::':" .
""-::::13-::";'.;'.f:·1I'~/er
Oil.'o Concrn,soMion troled .
Reverse osmosis]-'~f~
Osmosi
Porous fttddislribulor lub.
nullv.... '''''4:'1Opt/Nnd fibers
liD" bNndlu(lJ-slulptJ
Porous TubularSupporlmt1lu,,,'" .
.... IrItmliront
t.. ;
P.,ONSboriup d.isf
~~~~1l~
~piral-wound
. .'~
Conccn-~1tated
. ",
-,. ." . r •.•. ~ '\; :
Oil.te
)
FIG. 12. DRAWINGS OF SEVERALCOMMERCIALLY·AVAILABLE REVERSE OSMOSIS DESIGNS
(Reprinted with permission from POWER, June 1973)
MOTOR
CASING -11---1
1~IOUIO
OUT~ET
/I
I
/AOJUSTAB~E
UNI.OAOEAKNIFE
(a)
\'r--,J
FE EOIN~ET-
WASHIN~ET
SO~IOS
CAKE
\PERFORATEO
BASKET
REMOVABl.EVA~'1E PI.ATE
SOI.IOSOISCHARGE
CONVEYORORIVE SHAFT
~
I.I0UiOOISCHARGE PORTS
SCROI.1.CONVEYOR
.I.IOUIOOISCHARGE
CENTRIFUGEBOwl.
501.105OISCHARGE
PORTS
SHEAVE
(bJ
Figure 5-7 Typical centrifuge types (a) top suspended perforated-basket centrifuge and(b) helical conveyor solid-bowl centrifuge. Source: (DOE 1984).
WASTE SOLUTION -,
GLASS or CERAMIC 'CALCI NE
· -
,, '
ADDITIVES
ADSORPTION
EVAPORATIONand I or
CALCINATION PRESSURE
SINTERING
EVAPORATORend
MELTER MELTER
~
FURTHERTREATMENT
METAL MATRIX
orCOATED PARTICLE
Figure 1: Basic Solidification Processes
CAlCINAnON.. DDIIITES [. "Elt;ASI IN1'O '"i: I
"'''O'~HfRr . :
IllfR LOICO.. , 1... ' "0..
R[CE~"ON 0' PlSSION ~aoouc,.r--L-- ..... ~OLUlIOHS
a[~aOCHS'HG ~LAN'
'OR cONCr"'R..."ONOR TE"~ORMY
S'ORAGf 0'FISSION ~ROOUClS
.. .
'"
',H'''G Of. :O",..' ..fll
LID
•.....Z..
......·r-l~o..
. . L'OU'D:. .... :~.::. ['HUE .. ,S
Figure 2: Simplified flowsheet of vitrification plant at Marcqule (AVM)
REFRACTORY
.SCREW JACKFOR ON~F
ORA INCONTROL
m
ELECTRODES
BOTTOM DRAIN(fOR SHUT DOWN
ONLY)
PIVOT
COOLINGPLATE
.HLLW
ADDITIVES ---..l
OfF-GAS
LIQUID LEVELIN VAULT THERMOCOUPLES
LIQUID LEVELIN TANK
AIR MONITOIAND FILTER
Defense waste storage tank. (From The Safety ofNuclear Reactors and Related Faties, WASH· 1250, U.S. Atomic Energy Commission, July 1973.)
Subsidence
Electrode
MeltingZone
In situ vitrification. (Courtesy of the Pacific Northwest Laboratory.)
Rock
ACID •I GLASS FORMERSr----...
J
jlNORGANIC I~ ~
EXCHANGERTO REMOVE CESIUM I FEED
~ ICONCENTRATOR
---- I M:AKNEKUP I,,~ ~
OFF-GASSYSTEM
SUBMERGED BED SCRUBBER
CANISTER CLOSURE,INSPECTION, HANDLINC
AND STORAGE
~I
• •FEED DELIVERYI SYSTEM I
j r--f
SLURRY-FEDCERAMIC MELTER
MELTERFEEDTANK
RADWASTETREATMENT
SYSTEM
~CESIUM WASTE
fUPEANATANT
SLUDGE
THOREXWASTE
PUREX WASTE
Figure 2-4 Solidification of commercial high-level waste at West Valley. Source: (DOE1987).
. CHEMICALS
WASTE
/,I
II
II
II
~
SODIUMSILICATE
DRYCEMENTHOPPER
I.1I~--:a----'---- r"--'''' FILLPORT
CEMENT PAOOUCT INDRUMS lOR CASKS)
TO STORAGE
'J·lINE MIXING PROCESS FOR INCORPORATING RADWASTE IN CEMENT
DRYCEMENTHOPPER
EMENT PRODUCT CIN DRUMS .....-- ~Z7Z7Za
TO STORAGE
WASTE
,./
'*'
CHEMICALS
8. IN-DRUM MIXING PROCESS FOR INCORPORATING RADWASTE IN CEMl
CHEMICALS
WASTE--,
UREA-FORMALDEHYDESUSPENSION
IN-LINE MIXER
••:..•':...
CATALYST
FILLING ANDMIXING ASSEMBLY
(WITH DISPOSABLE f=!======loMIXER BLADE) :,
1-:to:
UREA-FORMALDEHYDEPRODUCT IN DRUMS (ORCASKS) TO STORAGE
STI RRED·VESSEL PROCESS FOR INCORPORATING RADWASTE IN UREAFORMALDEHYDE RESIN
EMlA.SION BRAKES
WETTING (Ilt~'-_AGENT
- RADIOACTiVE WASTESFROM PRETREATMENTAND PRECONCENTRATlONPROCESSES
CONTAINERS
HOlD TANK FORRADIOACTIVE SLURRIES
•TWIN·SCREW ORFOUR·SCREW MlXER·CONCENTRATOR
-CONDENSATE
DRAIN
~'I ~.. i! I TURNTAIlLE.,
I •
'IG.7. WERNER AND PFLEIDERER EXTRUDER/VAPORATOR PROCESS FOR VOLUME REDUCTION ANDSOLIDIFICATION IN ASPHALT
OTOR
RIve1
2.1 m
i3.8 m
5.5 m
-L-
~
Grode
,,•
Temperature gauge
• p ••,~-$j;Fi~- I~'....--...•. ~.. " \ ...•.. ,....... f.\
liquId level
gauge "
,.'
Air cooledcondenser
\leak detection0.20 m dry well
\
23 m die x 5.5 m high
Figure 2.4 Diagram of a tank for holding reprocessing waste. (Based on U.S.Department of Energy)
"~."._-.....---_.' ',~
~ CEMENT AND ADDITIVESARE BLENDED AND STOREDIN BINS '.",
Q) WASTE PUMPED TO MIXER
@GROUT PUMPED DOWN WEL
[
@SURGE AND MIXING TUB
-------HE SOLUTIONrANKS
EACH INJECTION IS ABATCH OPERATION
SUBSEQUENT INJECTIONSMADE BY INITIATING NEWFRACTURE HIGHER INWELL
~GROUT FORCED INTOFORMATION
Fig. 6. Hydrofracture flow sheet and operations.
,