Measurement and Control of Cement Set Times in Waste Solidification.

摘要

Fixation of radioactive waste in concrete was investigated on laboratory scale. Some cement formulations containing simulated or actual sludges from the Savannah River Plant had set times that would be too short for reliable handling in plant equipment. Set times could be controlled by use of excess water,but the concrete forms produced had inferior strength. A commercial organic retarder was found to be effective for increasing set times of cement-sludge formulations. However,the dosage of retarder required to control set times of high-alumina cement formulations was 1.0to 1.5wt percent of dry solids,which is 5to 10times the normal dosage for Portland cements. Data were obtained to predict the optimum content of retarder and water. (ERA citation 02:012526)