RELATIVE HUMIDITY TESTS IN SUPPORT OF THE 3013 STORAGE AND SURVEILLANCE PROGRAM

Mickalonis, J. ; Duffey, J.

Savannah River Site (S.C.)

关键词: Corrosion;    Storage;    Mixtures;    Humidity;    11 Nuclear Fuel Cycle And Fuel Materials;   

DOI  :  10.2172/1026681
RP-ID  :  SRNL-STI-2010-00409
RP-ID  :  DE-AC09-08SR22470
RP-ID  :  1026681

美国|英语

来源: UNT Digital Library

【 摘 要 】

Techniques to control the initial relative humidity over oxide/salt mixtures have been developed using cerium oxide as a surrogate for plutonium oxide. Such control is required to validate certain assumptions in the Department of Energy Standard DOE-STD-3013, and to provide essential information to support field surveillance at the storage sites for excess plutonium oxides. Concern over the validity of the assumption that corrosion induced degradation in 3013 containers could be controlled by assuring that the moisture content of any stored oxide/salt mixture was below 0.5 w t% arose when stress corrosion cracks were found in test samples exposed at room temperature to plutonium oxide/salt mixtures having a moisture content only marginally above 0.5 wt %. Additionally, analysis of the stress corrosion cracking observations suggests that the initial relative humidity over the oxide/salt mixture may play a major role in the cracking process. The investigations summarized in this report provide the procedures necessary to control the initial relative humidity to selected values within the range of 16 to 50% by controlling the loading relative humidity (18 to 60%) and the oxide/salt mixture water content (0.05 to 0.45 wt %). The studies also demonstrated that the initial relative humidity may be estimated by calculations using software EQ3/6. Cerium oxide/salt mixtures were used in this study because qualification tests with non-radioactive materials will reduce costs while increasing the breadth of the test programs required to support field surveillances of stored 3013 containers.