Kazuo MinatoJapan Atomic Energy Research Institute, Japan

Tetsuo IkegamiJapan Nuclear Cycle Development Institute, Japan

Tadashi InoueCentral Research Institute of Electric Power Industry, Japan

Resent Research and Development Activities on Partitioning and Transmutation of Radioactive Nuclides in Japan　

Eighth Information Exchange Meeting on Actinide and Fission Product Partitioning & Transmutation

Las Vegas, Nevada, USA9-11 November 2004

OMEGA Program in Japan

In Japan, the spent fuels from nuclear reactors are to be reprocessed

A long-term program for research and development on partitioning and transmutation (P&T) technology» Reduction of the burden of the backend of the nuclear fuel cycle

» The Atomic Energy Commission of Japan (AEC) began the program in October 1988.

» Advisory Committee of AEC reviewed the progress in 1999.

» The Committee issued the report in March 2000.

» OMEGA: Options for Making Extra Gains from Actinides and fission products generated in nuclear fuel cycle

OMEGA Check and Review in 2000

In P&T technology, there is a possibility to reduce the burden of waste disposal and to utilize waste as resources.

P&T technology is still on the fundamental stage. It is appropriate to steadily promote the research and development (R&D) and to demonstrate its feasibility. Then engineering tests are to be performed to obtain various knowledge such as safety data...

Three main institutes should promote their R&D steadily and effectively by collaborations with other institutes and universities in Japan and in foreign countries.

Innovative idea is required in the development of P&T technology. It is necessary to prepare attractive condition for young researchers and engineers where they can exert their full ability.

P&T Technology in Japan

In Japan, P&T technologies are studied mainly at three institutes:» JAERI (Japan Atomic Energy Research Institute)

» JNC (Japan Nuclear Cycle Development Institute)

» CRIEPI (Central Research Institute of Electric Power Industry)

JAERI is studying P&T technology using Accelerator Driven System (ADS) and dedicated transmutation fuel cycle.

JNC and CRIEPI are studying P&T technology using critical fast reactor fuel cycle. Their activities are now organized as the “Feasibility Study on Commercialized FR Cycle Systems”.

Other Remarks to P&T in Japan

Long-term Nuclear Program (2000)» “…… Although P&T is still on the fundamental stage of R&D,

there is a possibility to reduce the burden of waste disposal and to utilize waste as resources……”

Fundamental Policy for Specified Radioactive Waste Final Disposal (2000)» “…… Government and relevant institutes are required to steadily

promote the research and development of P&T technology to reduce burden of final disposal, where viewpoints of international collaboration and periodic evaluation are important……”

Final Geological Disposal

Spallation Target(Pb-Bi)

Pb-Bi cooledSubcritical core (k-eff=0.95~0.93)

Proton Beam (1.5GeV-30MW)

Pyrochemical Reprocessing

Fuel Manufactiring

Radioactive Waste without Long-lived Nuclides

MA, LLFP (Nitride Fuel)

Spent Fuel

MA, LLFP

(2nd Stratum)

Partitioning

High Level Waste

Partitioning & Transmutation Fuel Cycle(1st Stratum)

Reprocessing

Nuclear Power Plants

Commercial Fuel Cycle

Spent Fuel

U, Pu

Pu, MA, LLFP Recovered N-15

Electric Power30%

70%Grid

超伝導陽子加速器

電力

加速器へ 陽子ビーム 1GeV程度- 数10 mA

発電

加速器駆動 核変換システム (keff = 0.95)

再処理工場

高レベル廃棄物

群分離長寿命核種

短寿命核種

最終処分

長寿命放射性核種の処分は原子力利用にとって重要な課題。

本計画ではそれに向かう要素技術の基本的な実証をめざす。

実用プラント

未臨界炉心

Superconducting LINAC

JAERI’s Concept on P&TDedicated Transmutation Cycle with ADS

R&D on Partitioning ProcessJAERI

4-group Partitioning Process» For HLLW

» TRU, Tc-PGM, Sr-Cs, Others

» The process was tested with concentrated real HLLW

ARTIST Process» For spent fuel

» Phosphorus-free agents consisting of C, H, O and N (CHON principle)

– BAMA & DOHA : Separation of U, Pu

– TOGDA : An, Ln recovery

– N-donor ligand : An/Ln separation Amide-based Radio-resources Treatment with Interim Storage of Transuranica

ARTIST Process

BAMA process

Spentfuel

U

DOHA process

PuTc

TODGA processCs, Sr

recoveryprocess

An + Lninterim storage

N-donor process FP(Ln)

(Np,Pu), Am,Cm

BAMA process

Spentfuel

U

DOHA process

PuTc

TODGA processCs, Sr

recoveryprocess

An + Lninterim storage

N-donor process FP(Ln)

(Np,Pu), Am,Cm

R&D on Transmutation Fuel CycleJAERI

Nitride Fuel » Fabrication of (Pu,Am,Cm,Zr)N

» Property measurements

» Irradiation test of (Pu, Zr)N and PuN+TiN fuel pin in JMTR

– Irradiation: 2002-2004, PIE: 2005

Pyrochemical Process» Electrolysis of UN, NpN, PuN, (U,Pu)N

in LiCl-KCl eutectic melt» Recovery of Pu, U+Pu into liquid Cd cat

hode (Joint Research with CRIEPI)

» Nitride formation behavior of U, Pu in liquid Cd

(Pu,Zr)N PuN+TiN

20 mm

Liquid Cd cathod after recovery of Pu

Steam generator

Primary pump

Reactor vessel

Beam duct

Subcritical coreBeam window Core support

Fuel exchanger

Bending magnet

Movable support

Proton beam

Spallation target

R&D on Dedicated Transmutation SystemJAERI

Accelerator» Superconducting LINAC

» High-intensity proton accelerator (J-PARC Project)

Lead-Bismuth Eutectic (LBE)» Material corrosion/errosion test

» Thermal-hydraulics test for the beam window

» Evaporation test of Po from LBE

Sub-critical Reactor » 800 MWth ADS

» Transmutation of 250 kg of minor actinides annually Conceptual view of 800 MWth L

BE-cooled ADS

JNC’s Concept on P&TFast Reactor Fuel Cycle

Advanced fast reactor fuel cycle

Basic Standpoints» Treatment of all TRU in th

e same manner without distinguishing between Pu and MA

» Homogeneous loading of TRU in fuel assembly

» Classification of fission products into four categories

– Transmutation (Tc, I)

– Storage for cooling (Sr, Cs)

– Utilization (Ru, Rh, Pd, etc.)

– Waste

R&D on Radiotoxicity Reduction JNC

Next Process» New Extraction System for TRU

Recovery

» Advanced aqueous reprocessing method developed by JNC

» TRU recovery of > 99%

MA-bearing MOX Fuel» Fabrication

– 2%Np-2%Am-MOX

– 5%Am-MOX

» Irradiation Experiment– In fast experimental reactor JOYO

– In 2006MA-MOX irradiation experiment in JOYO

R&D on HLW Reduction JNC

ORIENT-cycle: Optimization by Removing Impedimental Elements

» New concept of fast reactor fuel cycle system

» Reduction of HLW: < 1/10

R&D on Utilization of Noble Metal FP JNC

Noble metal fission products» About 30 kg/t-spent fuel

» Electrolytic extraction of Ru, Rh, Pd, etc.

» Utilization as catalyst for hydrogen production by water electrolysis

Fission products of Sr and Cs» Utilization as

– radioactive source

– Heat source Experimental apparatus of electrolysis

Mining

LWR cycle

Enrichment

U, Pu

Aqueous reprocessing

FP

U, Pu, MA

U, Pu, MA, FP

U, Pu, MA, FP

MA：Minor actinideFP：Fission product

U

　

LWR

U, Pu, MA

Metal fuel FR

Fuel fabrication

Fresh fuel (Metal)

UUSpent fuel (Oxide)

Pyro-process with electrochemical reduction and fuel fabrication

Metal fuelled FR cycle

Pyrometallurgical process (Electrorefining)

Fuel fabrication

CRIEPI’s Concept on P&TFast Reactor Fuel Cycle

R&D on Partitioning ProcessCRIEPI

HLLW

Denitration

Multistage-extraction

>99% of TRU

Electrore-winningU

H2O, NOxAlkali metalsMo,Se,Tc

Reductive-extraction

LiCl-KClCl2

Noblemetals

Salt WasteTreatment

TRUs/REs = 1/10 (in weight)

TRUs / REs > 1 / 1

Waste

Chlorination(Fe,Zr,Mo)

Electrore-winning

Separation of U and TRU from HLLW» Conversion of HLLW to oxides b

y heat-treating at 500oC

» Chlorination of the oxides by chlorine gas at 700oC in LiCl-KCl

» Reductive extraction of noble metals in LiCl-KCl/Cd at 500oC

» Multistage extraction in the same system to separate U and TRU from rare earth elements

» Most of solvents, molten salt, liquid metal and chlorine gas can be recycled after treatment

Process flow of pyro-partitioning

Measurements of electrochemical potentials and distribution coefficients of actinides and lanthanides

Separation tests of actinides by reductive extraction» With simulated waste

» Recovery of > 99% actinides Setup of caisson in hot cell facilit

y (cooperation of ITU)

Electrorefining test of Pu recovery from metal fuel

Currently, the program proceeds to use the genuine HLLW to finalize the process flow

R&D on Partitioning ProcessCRIEPI

External and internal views of the caisson

U-Pu-Zr alloy before and after experiment

285808

100100467

1793

Na-bondingGas-plenum

A B

435 435

He-bonding

MOX driver

C

R&D on TransmutationCRIEPI

Characterization of Alloy with MA» Solubility of tri-valence species in U-Pu-Zr is less than 1 wt%

» Properties of alloys with MA and lanthanides up to 5% each are approximately the same as those of U-Pu-Zr

» No melting phase appears below 650oC in U-Pu-Zr/Fe couple (Pu/(Pu+U) < 25 wt%)

Irradiation test of MA-containing Alloys» U-Pu-Zr-MA-RE

» In core region of PHENIX

» METAPHIX-1: 2.4 at % (2004)

» METAPHIX-2: 7 at % (2004-2006)

» METAPHIX-3: 11 at % (2004-2008)

R&D activities for P&T technologies are summarized» JAERI: ADS transmutation fuel cycle with nitride fuel and pyro-process» JNC: fast reactor fuel cycle with MA-MOX and aqueous process» CRIEPI: fast reactor fuel cycle with metal fuel and pyro-process

Integration of JAERI and JNC is scheduled in 2005 Other activities in Japan

» Tokyo Institute of Technology– Basic study for innovative separation / transmutation systems toward vanis

hing HLW within the framework of COE-INES» Tokyo Institute of Technology

– Measurement and evaluation of nuclear data for MA transmutation in collaboration with JAERI, JNC, Kyoto University

» Kyoto University and High Energy Accelerator Research Organizatio (KEK)– Construction of proton accelerator to couple with an existing critical assem

bly, though the purpose of this program is not only for study of transmutation but also for energy production

Concluding Remarks