Reprocessed isotopic composition

Aqueous Process. In 1967-68, a hot reprocessing test had been conducted using the spent fuel (ca. 600 MWD/T) from JRR-3 (Japan Research Reactor-3) (6). About 200 g of purified plutonium was recovered by a modified PUREX process from aluminum-claded uranium fuels of natural isotopic composition. 

Some of the NDA verification techniques on samples of nuclear material taken during a safeguards inspection are carried out at specialized analytical laboratories, for example, the Safeguards Analytical Laboratory (SAL) at Seibersdorf in Austria or the On-Site Laboratory (OSL) at the Rokkasho Reprocessing Plant in Japan. Commercially available and customer-specific equipment is used to determine amounts and isotopic compositions of plutonium and uranium in inspection samples, having various chemical and physical forms, to supplement or replace destructive analysis. A parallel analysis of one and the same sample by NDA and DA serves the quality assurance of the analytical methods and control of the results. 

The dose fields associated with RU are higher than those associated with natural uranium. The isotopic composition and activity of unenriched RU UO2 powders depend inter alia on the reactor type, initial enrichment and discharge bumup of the PWR fuel, the time between spent PWR fuel discharge and reprocessing, the route chosen to convert the UNL to UO2, and the delay until fuel fabrication. 

Highlights The tolerance for impurities and isotopic composition of DU is quite large compared with the very strict specifications for nuclear fuel or for the feed material of enrichment plants (in fact, we did not find such specifications for DU). After dissolution of the DU, the analytical techniques used are basically the same for all forms of uranium. In cases where DU is fabricated from reprocessed fuel, some additional tests are required to verify the radioactivity. One feature of DU is that it is alloyed with different elements in order to improve its physical properties (like hardness or density) without any concerns about the nuclear properties of the alloy. 

The isotopic composition of the plutonium fraction of mixed-oxide fuels strongly depends on the production history (previous fuel enrichment and irradiation) of the individual plutonium batch supplied from the reprocessing plant. For... 

During the initial stages of development, it was assumed that the isotopic composition of plutonium in the fresh fuel would correspond to reactor-grade plutonium extracted from the cooled spent fuel of a typical light water reactor (e.g., from a 900 MW(e) PWR fuel irradiated up to a bum-up of 33 MW-d/kg U, reprocessed after 10 years of cooling) and loaded in the RBEC-M reactor in two years. The isotopic composition of uranium corresponds to depleted uranium with a content of 0.1 weight %... 

OOIS Ci Pu is released annually from a reprocessing plant. What will be the corresponding release of Pu and Pu for typical isotopic plutonium composition of LWR fuel ... 

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