工业废渣协同水泥固化放射性独居石废渣的配比与机理研究OA

Cement powder,fly ash,slag powder,and lime were used as curing materials to immobilize radioactive monazite waste.A 4-factor 3-level orthogonal experiment was conducted to study the variation patterns of unconfined compressive strength,uranium(U)and thorium(Th)leaching rates,freeze-thaw resistance,and acid neutralization capacity under different mix ratios.The optimal curing ratio was selected through fuzzy optimization theory,with curing mechanisms analyzed via XRD,FTIR,and SEM.Experimental results demonstrated that the slag-to-curing material ratio had the greatest impact on unconfined compressive strength and freeze-thaw resistance,while fly ash dosage significantly affected U leaching toxicity.All factors showed similar impacts on acid neutralization capacity,whereas Th leaching toxicity remained relatively unaffected.Using unconfined compressive strength,U leaching rate,freeze-thaw cycles,acid neutralization capacity,and curing cost as fuzzy optimization indicators,It is concluded through the fuzzy optimization that when the content of fly ash is fixed at 15%,the content of slag is in the range of 15%～25%,the content of lime is in the range of 2.5%～5.0%,and the slag-solid ratio is in the range of 1.0～1.4,the solidified body meet the requirements specified in Performance Requirements for Solidified Forms of Low and Intermediate Level Radioactive Waste-Cement Solidified Forms(GB 14569.1-2011)with a reasonable treatment cost.Post-curing treatment resulted in pore elimination,structural densification,and enhanced strength in the monazite waste solidification body.