Physical and decay characteristics of commercial LWR spent fuel

Abstract

Schematic of a typical Westinghouse fuel rod. 2-13Schematic of a typical Westinghouse fuel assembly* 2-14 Schematic of VANTAGE 5 fuel assembly. 2-15Schematic of a fuel rod from St. Lucie Plant-1 -2-16 14 X 14 array. 2.5Schematic of a fuel assembly from St. Lucie 2-17 Plant-1 -14 X 14 array. 2.6Schematic of a fuel rod from Arkansas Nuclear One, 2-18 Unit 2 -16 X 16 array. 2.7Schematic of a fuel assembly for Arkansas Nuclear (toe, 2-19 Unit-2 -16 X 16 array. 2.8Babcock and Wilcox fuel rod. 2-20 2.9 Babcock and Wilcox fuel assembly. 2-21 2.10 Typical General Electric fuel rod and assembly. 2-22 2.11 Cutaway diagram of an 8 x 8 General Electric fuel 2-23 assembly. 2.12 Cutaway diagram of QUAIH-fuel assembly. 2-24 2.13 Cutaway diagram of a partial QUAIH-fuel ass^nbly 2-25 showing internals. 2.14 Cutaway diagram of QUAIH-fuel channel. 2-26 2.15 Cutaway diagram of a QUAD-t-fuel assembly with 2-27 partially removed minibundle. 2.16Cutaway diagram of a QUAIH-fuel minibundle. 2-28 3.1Radioactivity produced by 1 metric ton of initial 3-7 heavy metal: PWR; 60,000 MWd. 3.2Radioactivity produced by 1 metric ton of initial 3-8 heavy metal: PWR; 33,000 MWd. 3.3Radioactivity produced by 1 metric ton of initial 3-9 heavy metal: BWR; 40,000 MWd. 3.4Radioactivity produced by 1 metric ton of initial 3-10 heavy metal: BWR; 27,500 MWd. C.lData collection pathway for spent fuel characteristics C.2 Calculational pathway for 0RIGEN2-generated data. C.3Construction pathway for the nuclear waste characteristics data base. XI LIST OF TABLES (continued) Table Page 3.17 Variation in neutron production (neutrons/s«MTIHli| ^ 3-40 spontaneous fission as a function of time since discharge from a 60,000-MWd/MTIHM PWR 3.18 Variation in neutron production (neutrons/S'MTIHM) by 3-40 spontaneous fission as a function of time since discharge from a 33,000-MWd/MTIHM PWR 3.19 Variation in neutron production (neutrons/s'MTIHM) by 3-41 spontaneous fission as a function of time since discharge from a 40,000-MWd/MTIHM BWR 3.20 Variation in neutron production (neutrons/s'MTIHM) by 3-41 spontaneous fission as a function of time since discharge from a 27,500-MWd/MTIHM BWR 3.21 Variation in neutron production (neutrons/s'MTIHM) by 3-42 the alpha-neutron reaction as a function of time since discharge from a 60,000-MWd/MTIHM PWR 3.22 Variation in neutron production (neutrons/s'MTIHM) by 3-43 the alpha-neutron reaction as a function of time since . discharge from a 33,000-MWd/MTIHM PWR 3.23 Variation in neutron production (neutrons/s'MTIHM) by 3-44 the alpha-neutron reaction as a function of time since discharge from a 40,000-MWd/MTIHM BWR 3.24 Variation in neutron production (neutrons/s'MTIHM) by 3-45 the alpha-neutron reaction as a function of time since discharge from a 27,500-MWd/MTIHM BWR 3.25 Variation in photon production (photons/s»MTIHM) as a 3-46 function of time since discharge from a 60,000-MWd/MTIHM PWR 3.26 Variation in photon production (photons/s'MTIHM) as a 3-47 function of time since discharge from a 33,000-MWd/MTIHM PWR 3.27 Variation in photon pr...

Multiple-barrier geological repository design and operation strategies for safe disposal of radioactive materials

“…For example, ORIGEN-2 calculations of radioactive decay in a 60 000 MWd/MTU pressurized water reactor spent fuel show that the initial activity of Ra-226 increases approximately by a factor of 2610 5 after 1000 years of containment, and by a factor of about 7610 7 after 100 000 years of containment (Roddy et al, 1986). Recent safety assessments for the disposal of spent fuel in long-lived copper canisters emplaced in fractured granite (SKB, 2006;Posiva, 2007) show that uranium-series daughter radionuclides (Th-230 and Ra-226) and neptunium-series daughter radionuclides (Th-229) can actually become significant contributors to the calculated dose rate for such repository concepts, despite the fact of the trivial initial abundances of these daughter radionuclides in spent fuel (Roddy et al, 1986).…”

A review of near-field mass transfer in geologic disposal systems

“…For an clement with isotopes that decay appreciably during the time of interest, a solubility boundary condition results in a time-dependent boundary concentration of each isotope. Decay Constant (A) per year 0 0.024 Browne and Firestone 1986 Isotopic fraction (7) 0.4 0.6 Browne and Firestone 1986 Initial Inventory (M°) g/MTHM 349 519 Roddy et al 1986 Retardation Coefficient (A') 200 Dilfusion Coefficient (D) m'/a 3 xlO" 3 Elemental Solubility (c, e ) g/m 3 0.01 Pigford ct al. 1983 To illustrate, we consider the release of solubility-limited strontium, consisting of radioactive 90 Sr atid stable M Sr, from spent fuel waste surrounded by porous rock.…”