Technology for cleaning of Pb-Bi adhering to steel, 1; Basic tests

Saito, Shigeru; Sasa, Toshinobu; Umeno, Makoto*; Kurata, Yuji; Kikuchi, Kenji; Futakawa, Masatoshi

JAERI-Tech 2004-074, 41 Pages, 2004/12

JAERI-Tech-2004-074.pdf:24.5MB

The accelerator driven system (ADS) is proposed to transmute minor actinides (MA) in high-level waste from spent fuels of nuclear power reactors. Liquid Pb-Bi alloy is a candidate material for spallation target and coolant of ADS. Pb-Bi cleaning technology is required to reduce radiation exposure during maintenance service and to decontaminate replaced components. In this study, three cleaning methods were tested; silicon oil cleaning at 170C, mixture of acetic acid and nitric acid cleaning. Specimens were prepared by immersion in melted Pb-Bi. After silicon oil tests, most of Pb-Bi remained on the surface of the specimens. It was found that blushing was needed to remove Pb-Bi effectively. On the other hands, Pb-Bi was easily dissolved and almost removed in the mixed acid and nitric acid. Silicon oil cleaning did not affect on base metals. The surface of base metals was slightly blacked after mixed acid cleaning. F82H base metals were corroded by nitric acid.