Status of SNF Pyro Reprocessing

RIAR, Dimitrovgrad, Russia

Mikhail Kormilitsyn

Research Institute of Atomic Reactors (RIAR)Radiochemical Complex

SSC Research Institute of Atomic Reactors. RUSSIA

RIAR General Goal

Research Reactors PIE Radionuclide Productions

Fuel Supply of BOR-60/MBIR

Closing of FC

Advanced Fuel development

and testing

Demo of Closed Fuel Cycle

MA recycling

R&D for MSR Fuel Cycle

Fundamental Studies

RAW Treatment

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Universal technological platform for decisions in the field of Closed Fuel Cycle of Nuclear Power:

• No limitation for: fuel types (oxides, nitrides, metal, carbides, cermet, MSR, IMF) burn up, cooling time

• No limitation for requirements of decontamination factor (DF up to 106)

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New Generation Technological Package“Pyro-Chemistry for CFC”

New Generation Technological Package“Pyro-Chemistry for CFC”

• The Base System – Molten chlorides The Base processes

Dissolution of initial SNF ( chlorination or anodic dissolution) Electrolysis on solid and/or liquid cathodes Precipitation Purification of the melt

• Option – Technology of fluoride volatility• Option – Partitioning in fluoride melt • Option – chemistry and technology of molten fluoride fuel

of MSR

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R&D on SNF Pyro Reprocessing in a World

• Oxide SNF reprocessing into Oxide – RIAR (Russia), JNC/JAEA (Japan)• Oxide SNF reprocessing into Metallic – CRIEPI (Japan), KAERI (Korea)• Nitride SNF reprocessing – JAERI/JAEA (Japan), RIAR (Russia)• Metallic SNF reprocessing – INL, ANL (US), CRIEPI (Japan), RIAR

(Russia) • SNF metallization – KAERI (Korea), RIAR (Russia)• HLW partitioning in molten salts – CRIEPI (Japan), RIAR (Russia), KAERI

(Korea), CEA (France), ITU (EU)• Fluoride volatility processes – CRIEPI, Hitachi/TEPCO (Japan),

Kurchatov Inst., RIAR (Russia), INR (Czech. Rep.)• MSR Fuel Cycle – RIAR, Kurchatov Inst., CNRS (France), Institute for

Applied Physics, Shanghai (China)• Other application

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RIAR Experience

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RIAR activities in the field of CFC

Since 1964 RIAR has been pursuing large-scale investigations in the following research lines:

Pyrochemical production technology of vi-pack U and MOX fuel Pyrochemical reprocessing of SNF from nuclear reactors of various types . Fluoride volatility reprocessing of SNF

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Milestones of Experience in Closed Fuel Cycle

• Pyro R&D- from early 1960-s• Demo of fluoride volatility reprocessing – 1970s• Pilot facility for pyro/vi-pack MOX fuel production for fast reactor – from

late 1970-s • BOR-60 full scale fuel supplying only on the base of own RIAR

pyro/vi-pack fuel production facilities – from 1980• Pyro reprocessing experience – from 1991• Study on transmutation cycle, nitride fuels and others – from 1992• Start of industrial implementation of pyro/vi-pack MOX technology – 2012• Start of so called “high density” FR SNF (nitride, metal) - 2010• Creation of “Poly-functional Radiochemical Complex” (PRC) -2010-2017

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RIAR experience in reprocessing of spent fuel of the BOR-60 and BN-350 reactors

Fuel type Burn-up % h.a.

Cooling time, Yrs Weight, kg Date Reactor

UO2 7,7 5 2,5 1972..1973 BN-350

MOX 4,7 10 4,1 1991 BN-350

MOX 21..24 1-2 6,5 1995 BOR-60

UO2 10 15 5 2000 BOR-60

MOX 10 10 12 2000…2001 BOR-60

MOX 16 4-6 5 2004 BOR-60

U-Pu /Na 6,4 19 0,13 2010 BOR-60

(U,Pu)N /Pb 0,53 8 0,28 2010 BOR-60

U-Zr / Na 9,7 9,5 0,12 2010 BOR-60

U-Pu-Zr /Na 9,7 9,5 0,10 2010 BOR-60

MOX 15 5 4 2011 BOR-60

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Dimitrovgrad Dry Process (DDP) – MOX Fuel Pyro processing

Basic research of the molten salt systems allowed for the development of technological processes for production of granulated U and Pu dioxides and MOX.

A distinctive feature of the Pyro technology is a possibility to perform all the deposit production operations in one apparatus - a chlorinator-electrolyzer

Pyrochemical reprocessing consists of the following main stages

• Dissolution of initial products or spent nuclear fuel in molten salts

• Recovery of crystaline Pu dioxide or electrolytic MOX from the melt

• Processing of the cathode deposit and production of vi-pack

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Production and testingof vi-pack MOX fuel

Fuel type Number of FAs

Burn-up, max.%

Load, kW/m

Temperature, 0С Reactor

(U, Pu)O2Civil grade/ orweapon quality

330 30,3 51,5 720 BOR-60

UO2 + PuO2

Civil grade/ orweapon quality

132 14,8 45 705 BOR-60

(U, Pu)O2 Weapon grade 26 11,1 46 680 BN-600

(U, Pu)O2 Civil grade 4 development of the production technique BN-600

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DDP MOXPuO2 flow sheet

Cathode(pyrographite)

StirrerStirrer

UO2

2+

O2

Pu4

+ PuO2

2

+

+

Pu4

+ UO22+

UO2 PuO2

UO22+

UO2 +

NpO2

Cl2 Ar (Cl2) Cl2+O2+Ar Cl2+O2+ArStirrerCathode

Na3PO4

+

Fuel chlorination

700 оС

pyrographite bath,

NaCl - KCl

Preliminary electrolysis

680 оС

Precipitation crystallization

680 оС

Electrolysis-additional 700

оС

Melt purification700 оС

UO22+

PuO2

Cl-

(MA,REE) RW4

UO2

MA,REE

NpO2+

Cathode(pyrographite)Stirrer

UO2

2+

+

Pu4

+ UO22+

UO2 PuO2

Cl2 Cl2+O2+ArStirrerCathode

Na3PO4

Fuel chlorination

650 оС

pyrographite bath,

NaCl -2CsCl

Electrolysis-additional 630

оС

Melt purification6500 оС

Cl-

(MA,REE) RW4

MA,REE

UO22+

UO2 +

NpO2

Ar (Cl2)

+

Preliminary electrolysis

630 оС

NpO2+

DDP MOXMOX flow sheet

UO22+

MOX

Cl2+O2+Ar

+

Main MOX electrolysis

630 оС

PuO2+ PuO2

+

MOX

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MOX-MOX Reprocessing

2004 YearMOX - 3 400 g Pu content - 33,5 % wt.

2000 YearMOX - 3 200 gPu content - 10 % wt.

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Pyro HLW treatment

Salt residueSalt

purificationPyroreprocessing

Na3PO4

Phosphates

Fission products

Radioactive Cs

NaClCsClNdPO4C

ePO4

Waste Phosphates Salt residue

Special features contain fission products

Alkaline metal chlorides, high activity, significant

heat release

Basic elements 11 wt.% Nd4,4 wt.% Ce

81,96 wt.% CsCl18,04 wt.% NaCl

Quantity* <0,15 kg/kg of fast reactor SNF

<0,03 kg/kg of fast reactor SNF

14* - TOSHIBA estimation for DDP

Characteristic

HLW type

Phosphate precipitate

Spent salt electrolyte

Phosphate precipitate + spent

salt electrolyte

Glass matrix typePb(PO3)2

NaPO3

NaPO3, AlF3

Al2O3

NaPO3, AlF3

Al2O3

Introduction method vitrification, Т=9500С

vitrification without chloride

conversion, Т=9500С

vitrification without chloride conversion,

Т=9500С

Introduced waste amount, % 28 20 36

137Cs leaching rate as of the 7th day, g/cm2 * day 7*10-6 7*10-6 4*10-6

Thermal resistance, 0С 400 400 400

Radiation resistance 107 Gr (for and ) 1018 -decay/g

Vitrification of HLW from pyro process

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Characteristics Type of high-level wastes

Phosphate deposit Spent salt electrolyte

Type of ceramics monazite Cosnarite (NZP)

Method of introduction into ceramics pressing, calcination , Т=8500С

Conversion to NZP from the melt or aqueous solution, pressing,

calcination , Т=10000С

Quantity of waste introduced into ceramics, % 100 30..40

Leaching rate of 137Cs on 7-th day, g/cm2 * day 1*10-6 3*10-6

Thermal stability, 0С 850 1000

Radiation resistance 5*108 Gy( for and ) 1019 - decay/g

Ceramization of HLW arising from pyro process

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RIAR R&D PROGRAM DOVITA

Since 1992• Dry technologies• Oxide fuel with MA• Vi-pack• Integrated disposition on the same

site with the reactor • TA Transmutation of Actinides

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Experience in DOVITA Program

Irradiated (U,Np)O2 fuel, 19% burn-up

Pyrochemical technology of adding Np into oxide fuel (5-20%) has been developed

Performance of vi-pack fuel with (U,Np)O2 fuel has been validated experimentally to ~20% burnup in BOR-60

No evidence of significant difference in performance of fuel rods with (U,Np)O2 fuel compared with UO2 or MOX fuel rods has been noticed

Pyrochemical process of codeposition of Am with MOX fuel (2-4%) has been developed

Methods of Am/REE separation in melts has been tested Special vi-pack targets containing Am oxide with UO2 or

inert matrix have been developed Transmutation of Np, Am, Cm is being studied in BOR-60

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New times consideration:

DOVITA DOVITA-2 1992 Dry technologies Oxide fuel with MA Vi-pack Integrated disposition

same site with the reactor

TA Transmutation of Actinides

2007+Dry technologiesOn-site reprocessingVarious type of fuel with

MAIntegration of MA

recycling into FR Closed Fuel Cycle

TA - Transmutation of Actinides 20

DOVITA-2

Fuel type/ Stages

Oxide vi-pack

Oxide pellet

Nitride vi-pack

Metal Molten salt

Concept Studies

+ + + +/- +R&D + -/+ +/- - +Fuel

Production+ - - - -

Irradiation Testing

+ - - - -PIE + - - - ----

Reprocessing -/+ - - - +/-

DOVITA-121

Current R&D

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In the Frame of Federal Target Program

For the First Time in a World – pyrochemical reprocessing

of FBR spent U-Pu nitride fuel and metal fuel

~ 0,6 kg SF

2 Cd ingots for fabrication of fuel

Oxide concentrate FP for wastes preparation

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Experimental Tests of Spent Nitride Fuel Reprocessing Methods

The empty pies of cladding after anodic dissolution of nitride SNF in chloride melt

The sample of fluoride-phosphate glass with real immobilized FPs after reprocessing

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100% PuO2 Pyro Pellets

Melted salt 3LiCl-2KCl NaCl-2CsCl

Pellets density, g/sm3 8.5-10.2 9.8-10.3Visual view no cracks no cracs

PuO2 Pellets(NaCl-2CsCl, T=550oC)

PuO2 Pellets(3LiCl-2KCl, T=450oC)

PuO2 Pellets Characteristics

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80%UO2 + 20%PuO2 MOX Pyro Pellets

Batch № 1 Technical Requirements*

Pellet density, g/sm2 10.2-10.4 10.2-10.7

Deviation of pellet density, g/sm2

+0.1 +0.1

O/Me 1.98 1.97+0.01

Impurities content, % масс.

<0.3 <0.4

Average size of crystalline granules, microns

30-40<50

Visual view no cracks no cracks

Porosity uniform uniform

*Reshetnikov Ph.G. and et al. Working out, production and operation of fuel rods of power reactors-M:.Energoizdat, 1995-320p.

MOX Pellets Characteristics

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0

10

20

30

40

50

60

70

80

90

3000 3500 4000 4500 5000 5500 6000

Расстояние, мкм

Мас

сова

я до

ля U

, Pu,

%

U Pu

μm

Cont

ent,

wt%

Composition of pellet Medium of powder production

Insoluble residue, % wt.

Residue composition, wt%

80wt%UO2

+20wt%PuO2

3LiCl-2KCl 0.14 (Pu0.81, U0.19)O2

3LiCl-2KCl 0.14 (Pu0.49, U0.51)O2

NaCl-2CsCl 0.40 (U0.65, Pu0.31,Am0.04)O2

EPMA

Solubility test in 8M HNO3 at 95-96оC , duration – 10 hrs.Pickled pelletUnpickled pellet

Microstructure of MOX pellets

Pyro MOX pellets (80%UO2 + 20%PuO2)

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Fuel pin #TM0-01 with pyro MOX pellets

Dismountable BOR-60 FAs

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Fundamental Studies

Curium containing salt for spectroscopy studies NaCl-2CsCl-CmCl3(0.115mol/kg)

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-0.05

0.25

0.55

320 370 420 470 520

wave-length, nm

tran

smis

sion

den

sity

Spectrum of curium-containing melt under atmosphere of Ar- HCl-H2O

NaCl-2CsCl-CmCl3(0.115mol/kg)750oClog(P2HCl/PH2O)=-7.14

Cm3+

Am3+

CmO+

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Cavity from optical quartz

Oxygen sensor

Oxygen pump

CE

RE

Gas-supply tube

Synchronized potentiometric titration by oxygen pump and spectroscopy

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MA and FP Partitioning

-1.6

-1.4

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

0 200 400 600 800 1000 1200 1400

Time, sec

I, A

Ga cathod

Run #

T,oC Weight, g Content in melt, % E, V

(Li,K,Cs)Cl Ga Am Ce

1 350 200 95 0.6 3 -1.2

2 350 200 95 0.6 3 -1.4

3 350 200 95 0.6 3 -1.6

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Experimental Facilities till 2020

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RIAR Site

Post Irradiation complex

RadioWaste complex

Chemical-Technological complexRadiochemical

Complex

R&D on Reprocessing

and Refabrication

of Advanced Fuels

Post Irradiation Examination

MBIR

Вибро

MOX or other fuel

ПироRefabricated Fuel

Отходы на хранение

electricityHeat powerradionuclides

Pyro

Vi-pack

RAW

RIAR Radiochemical Complex

CFC Pyro technology for International RIAR-based Center of

Excellence

MOX Production

Facility

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Federal Tasks-oriented Program “New Generation Nuclear Power Technologies”

• Large Poly-functional Radiochemical Complex (PRC) - 2017

Molten salt Reprocessing Facility (1st hot cell line) capacity – up to 1-2 tons of FR SNF per Year (fuel type: oxide, nitride, metallic, IMF)

Advanced water-technology Facility, (2nd hot cell line) capacity – up to 1-2 tons kg of SNF per Year

• New Lab for Experimental and Innovative Fuel Production – 2010-1017 (incl. Fuel and Targets with MA)

• New facility for HLW treatment• Demonstration of Closing Fuel Cycle • Testing and Demonstration of Closing FR Fuel Cycle for MA • Develop the full scale Design of Industrial plants for FR SNF Reprocessing

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List of Advanced R&D for PRC• Testing of prototypes of technological equipment• Development and testing of automatic and robotics systems• Comparative FS for different technologies• Advanced thermo-chemical decladding technologies • Voloxidation• Pyrochemical molten salt technologies

MOX fuel Mixed Nitrides Metallic IMF, MSR

• Remote control fabrication technologies Vi-pack Pelletizing Metallic

• RAW treatment• Vitrification• Ceramization 37

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THANK YOU FOR ATTENTION!

RIAR Radiochemical Complex