IAEA Sources of Radiation Fuel Cycle - Reprocessing Day 4 – Lecture 8 (2) 1

IAEA Reprocessing 2

IAEA What is reprocessing?  Reprocessing is the separation and removal of fission products from the SNF  U, Pu may be separated and reused or stored  Fission products vitrified as HLW glass (ideally)  Many processes  wet  dry  transmutation 3

IAEA Reprocessing  Spent Fuel  95% 238 U  1% 235 U  1% Pu  3% fission products  Reprocessing separates it into 3 groups  U  Pu  Waste 4

IAEA Reprocessing 5

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IAEA What is the Wet Route?  shear, dissolve fuel in nitric acid  clarify, solvent extraction  partition U/Pu  recover UO 3, PuO 2 powders  Purex variations most successful  % recovery of U/Pu 8

IAEA What are the Facilities?  Several large facilities for power reactor SNF  All heavily shielded - 4 ft walls  Cells, manipulators, remote operations  France - La Hague  2 plants, about 1,700 te/yr capacity  running at 1,500-1,600 te/yr  Bq vitrified HLW  UK - Sellafield  2 plants  THORP - about 700 te/yr (800 capacity)  0.3 x Bq vitrified HLW 9

IAEA Dry Reprocessing  Sometimes called pyroreprocessing, pyrometallurgical  Uses melting, electrolysis, volatilization to separate U/Pu from fission products  Proposed in transmutation schemes  Difficult to adapt to commercial fuels 10

IAEA Transmutation Perform nuclear processes and reactions on radioactive wastes to render them either non- radioactive or significantly less radioactive so that radiotoxic and disposal concerns are substantially reduced or eliminated. 11

IAEA Why Transmutation?  Some Fission Products and Transuranics radioactive/hazardous for 10,000+ years and environmentally mobile  Why not transmute them into stable (nonradioactive) or short-lived materials?  Why not reduce quantities, isotopes, types going to disposal?  Ideally, only LLW disposal requirements needed  Main focus on Actinides (Np, Pu, Am, Cm)  Secondary focus on Tc, I, Ni, Zr  Tertiary focus on Cs, Sr 12

IAEA What does this mean?  Methods can reduce the risks of SNF/HLW disposal  Not obvious that any route can meet desired destruction % for LLW  All require significant money and take time 13

IAEA World Commercial Reprocessing Capacity CountryLocationLWR fuel tonnes/yr FranceLa Hague1,600 UKSellafield (THORP)1,200 RussiaChelyabinsk (Mayak)400 Japan90 Total2,940 Other nuclear fuels: UKSellafield1,500 FranceMarcoule400 India200 Total2,100 Total civil capacity5,040 14

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IAEA Reprocessing  Occurs 5 – 25 years after removal from reactor  Partitioning  Separate individual radionuclides  Transmutation  Neutron bombardment converts one radionuclide into another with better characteristics  Radiotoxicity reduced within 1000 years 16

IAEA Reprocessing  PUREX process  Dissolving fuel  Separation of U and Pu by solvent extraction  Remaining 3% is HLW – vitrified pending disposal  UREX process  Proposed by USA – only U recovered 17

IAEA Reference  International Atomic Energy Agency, Postgraduate Educational Course in Radiation Protection and the Safety of Radiation Sources (PGEC), Training Course Series 18, IAEA, Vienna (2002) 18