Spent nuclear fuel project recommended reaction rate constants for corrosion of N-Reactor fuel

Abstract

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Uranium oxidation rate summary for the spent nuclear fuel project

“…Equation (5-3) and (5-4) are based on correlations of literature data identified by Cooper, 1998. Both correlations are dependent on temperature The rate observations at 10% to 75% relative humidity vary froin equivalent to dry air at 30°C to equivalent to 100% relative humidity air at approximately 100°C.…”

“…Both correlations are dependent on temperature The rate observations at 10% to 75% relative humidity vary froin equivalent to dry air at 30°C to equivalent to 100% relative humidity air at approximately 100°C. Complex reaction kinetic models that attempt to describe the relative humidity relationship froin the literature were identified in Cooper, 1998. However, for simplicity, a linear interpolation between data correlations was developed for SNF process design (see Figures 5-1 and ti-2 also compare literature data observations to the design and safety basis oxidation rates based on enhancement factors of 3 and 10, respectively (from Reilly, 1988).…”

“…These generally record the data available from literature reviews that formed the initial correlations presented in Cooper, 1998 and present regression analyses ofthe data.…”

Safety analysis report for packaging (onsite) multicanister overpack cask

“…The hydride in the corrosion product attached to the uranium metal is accounted for as part of the uranium reaction rates given in equations (1) to (10) The rate at which the indicated uranium/water or uranium/oxygen reactions occur are a function of the temperature of the uranium, the partial pressure of water (if present), and the surface area involved. The relationships for the chemical reaction rates are taken from the recommendations made in Cooper (1996b) for the corrosion of N Reactor fuel. The relationships consist of Arrhenius Rate Law type equations developed by Pearce (1989) and Ritchie (1981Ritchie ( , 1986 …”

“…A factor of 10 is recommended by Cooper (1996b) to account for these effects. As such, the equivalent worst-case MCO surface area to be used with the reaction rate equations is 1,200,000 cm after the surface area adjustment factor is included.…”