An Evaluation of gas generation from metal waste (IV); Data acquisition and evaluation of gas generation rate uner aerobic condition

Wada, Ryutaro*; Nishimura, Tsutomu*; not registered; Fujiwara, Kazuo*; Tateishi, Tsuyoshi*

In order to evaluate the hydrogen gas generation rate due to the corrosion of metallic materials contained in TRU wastes, the ampoule type immersion tests (the test specimen and test solution are enclosed into a glass ampoule) have been performed following the last year. The gas generation tests on zircaloy, stainless steel and carbon steel were performed under the aerobic condition in this year. (1)The hydrogen gas generation rates due to the corrosion of stainless steel (SUS304) in simulated underground water (pH813.5) were 0.010.15m/y (oxygen concentration = 20%) and 0.1m/y (oxygen concentration = 1%). (2)The hydrogen gas generation rate due to the corrosion of carbon steel (SPHC) in simulated underground water (pH813.5) ranged in equivalent corrosion rate of about 0.0212m/y (oxygen concentration = 20%) and 0.3m/y(oxygen concentration = 1%) depending on the composition of test solution, and the ranking by pH of solution was pH8 pH10 pH13.5 pH12.5. (3)The hydrogen gas generation rate due to the corrosion of zircaloy in simulated underground water (pH1013.5) decreased with the immersion time, and the equivalent corrosion rate after immersion of 30180 days was 0.004m/y. (4)The corrosion rates of zircaloy, stainless steel and carbon steel based on oxygen were higer than that on the hydrogen gas generation.