Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

PROCESSING OF 5.4-YR DECAYED Zr-U ALLOY FUEL IN THE VOLATILITY PILOT PLANT (RUNS R-5 AND R-6)

Technical Report ·
OSTI ID:4717189
Disso1ution oi two 5.4-yr decayed Zr--U alloy fuel eleraerts with 75-150 g/min of anhydrous HF was performed in two runs at 495 to 650 deg C in NaF- LiF- ZrF/sub 4/ salt. Separation of uranium from fission products was accomplished by fluorination at 500 to 520 deg C with elemental fluorine at a dual flow rate of 8 and 13 slm for 120 to 150 min. Puriiication of the UF/sub 6/ from trace fission products was accompllshed by an absorption-desorption cycle on NaF at 100 and 400 deg C, respectively. Product UF/sub 6/ was collected in a cold trap. Breakthrough of Ru/sup 106/ to the UF/sub 6/ product occurred in run R-5, and again in R-6 along with Sb/sup 125/. The breake purge gas flow and nonoptimum absorber bed operation. Ru/sup 106/ and Sb/sup 125/ d.f.'s were 5 x 10/sup 4/ and 10/sup 3/ to 10/sup 5/, respectively, after breakthrough. Other specific decontamination factors were 10/sup 9/ for Cs/sup 137/, Sr/sup 90/, and TRE BETA ; 10/sup 4/ to 10/sup 5/ for Zr--Nb/sup 95/, and 10/sup 5 / to 10/sup 7/ for Gr BETA - gamma . Tc/sup 99/, MoF/sub 6/, and Np/sup 237/ continued to contaminate the product. Proposed methods for product improvement are outlined. Fuel element dissolution rates were 2.5 to 2.9 kg/ hr. Fluorine utilization efficiency was low (2 to 3%) in both runs. Uranium losses to the waste salt were 0.36 and 0.08%. (auth)
Research Organization:
Oak Ridge National Lab., Tenn.
DOE Contract Number:
W-7405-ENG-26
NSA Number:
NSA-17-010742
OSTI ID:
4717189
Report Number(s):
ORNL-TM-447
Country of Publication:
United States
Language:
English