In our country, the treatment and disposal of radioactive wastes from fuel reprocessing plant will be of great importance within a few years. From this prospect, studies on the possiblility of disposing these wastes into the deep sea are urgently needed. In this study, neutralized liquid waste having the same chemical composition as one from Purex-reprocessing was solidified with cement, then the compression strength of the specimen and the factors affecting to its strength were examined. Results are as follows.
1) Generally, compression strength was reduced exponentially with the increase of waste-cement ratio weight or with the dilution of the waste with tap water.
2) The largest strength, 680kg/cm
2, was obtained in the case of solidifying the waste neutralized with Ca(OH)
2 under conditions of no dilution of the neutralized waste, waste-cement ratio of 120% and curing time of 28 days. In the case of neutralization with NaOH, the largest strength was 420kg/cm
2.
3) Volume increase ratio between the solidified cement specimen and the waste water before solidification was 1.5 in the case with Ca(OH)
2, 1.7 with NaOH under the same conditions as above.
4) Important factors affecting to strength were dilution of the waste and waste-cement ratio when Ca(OH)
2 was used as neutralizer, and waste-cement ratio and curing time in the case with NaOH.
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