Drying damaged K West fuel elements (Summary of whole element furnace runs 1 through 8)

Abstract

Reason for Transmittal IG) Disposition IH) & (I) i. S. a. D or NIA 1 Approval 4 Review 1 Approved 4 Reviewed nolcornmenf see WHC-CM-3~5. 2 Release 5 Post-Review 2. Approvsd wicornment 5. Reviewed wicomrnent jec.12.71 3. Information 6. Dibt. IRscsipt Acknow Required) 3. D~sappr~vsrl wlcornmant 6. Receipt acknowledged 1 7 SlGNATURElDlSTRlBUTlON (See Approval Daeignator for required signatures) [ I Approved u/comnents [ 1 Disapproved W c m n t s BD-'WC-172-1 HNF-3377, Rev. 0

Uranium oxidation rates issue closure package

“…Hot cell studies that dried N Reactor fuel elements in moist inert gas, where rates can be inferred from isothermal periods at 5OoC and 75'C (Lawrence, 1998) Fuel clement shipping observations at approximately 20°C, where gas generation rates were measured (Briggs and Roe, 1997, Attached as Appendix 10.1 to Pajunen, 1999) Assessment of all relevant reaction rate data has been documented in Pajunen, 1999 which confirms that the reaction rates currently used in SNF Project calculations are appropriately conservative. Peer review of Pajunen, 1999 was provided by Fauske and Associates.…”

“…Single element drying test procedures also reflect the concept of performing hot conditioning steps, including a final heating of elements to 400°C (Lawrence, 1998). However, reaction rate data for the water vapor oxidation reaction can be inferred from isothermal periods in the drying experiment procedure, which occur at temperatures of 50°C and 75'C.…”

Uranium oxidation rate summary for the spent nuclear fuel project

“…Reaction rate estimates from complete elements (generally outer elements were tested) can be derived from hydrogen generation measurements by assuming the reaction stoichiometry shown by Equation (4-3). Hydrogen generation rates from entire elements in a water vapor system were observed during single element drying tests in the laboratory hot cell The individual drying test reports are summarized and compared in Lawrence, 1998. Single element drying tests produced hydrogen generation rate measurements during constant temperature operation at 50°C and a partial pressure ofwater vapor of approximately 1 Wa (-10 torr) from two elements (Runs 7 and 8). Hydrogen generation rate measurements are also available from five elements (Runs 4 through 8) at a constant temperature of 75°C and partial pressures of water vapor ranging from 0.001 kPa to 0.027 kPa (-0,008 torr to 0.2 torr).…”

“…Drying was performed at temperatures up to 400°C. While axial cracks in elements were reported to open further during the drying process, no significant fuel fragmentation is reported or indicated by to post-drying photographs (Lawrence, 1998 (Briggs and Roe, 1997) summarize N Reactor Fuel shipping observations obtained during the transfer of fuel samples to the laboratory The following table of reaction rates, derived from the observations, is taken from Praga, 1998 …”

Uranium Oxide Rate Summary for the Spent Nuclear Fuel (SNF) Project (OCRWM)

“…Hydrogen generation rates from entire elements in a water vapor system were observed during single element drying tests in the laboratory hot cell. The individual drying test reports are summarized and compared in Lawrence, 1998. Single element drying tests produced hydrogen generation rate measurements during constant temperature operation at 50°C and a partial pressure of water vapor of approximately 1 ! @a (-10 torr) from two elements (Runs 7 and 8).…”