The Results obtained from the 20 years of "Monju" plant data, 8; Purity management of sodium

Nakamura, Yoshihide; Sawazaki, Hiromasa; Morioka, Tatsuya; Uchida, Takenobu; Sato, Takeshi; Shiotani, Hiroki; Kisohara, Naoyuki 

With the liquid metal sodium cooled fast reactor, sodium has to be maintained and managed at a high purity to prevent the channel blockage by the precipitation of impurities and the material corrosion with sodium. At Monju, primary heat transport system, secondary heat transport system, and ex-vessel fuel storage tank sodium cooling system are corresponding to this clean-up system. We evaluate the sodium purity control condition of these facilities for more than 20 years by the measurement of the plugging meter and chemical analysis, and confirm that we could maintain the purity with a value lower enough than the management targeted value.