2013 Volume 39 Issue 4 Pages 405-410
Chemical interface controlled dispersion and high-speed shearing water washing tests were carried out with highly radioactive contaminated soil of over 570,000 Bq/kg in Fukushima. In present experiment, ion plating Al2O3 ceramic coating was applied to SUS304 substrate material for prevention of radioactive contamination, and its erosion and decontamination performance were assessed. The following results were obtained. (1) Adhesion of fission product (FP) contained in refined soil particles was observed on the surface of SUS304 test coupons coated with 5 µm of Al2O3. In wipe-out tests, contaminated soil particles were easily removed from the surface of Al2O3 coated test coupon, whereas contaminated soil particles were tightly bound to the surface of uncoated SUS coupons. (2) The erosion rate of uncoated SUS coupons was estimated as 0.94 µm/h within 1 h of soil washing operation, after which no erosion was observed. Very slow erosion of 0.14 µm/h was observed in the case of Al2O3 coated test coupons during the soil washing process.
