岩土工程学报2025，Vol.47Issue(1)：57-64,8.DOI:10.11779/CJGE20230991
碱激发高炉矿渣固化/稳定化Cr(Ⅵ)污染土试验研究
Experimental study on solidification/stabilization of Cr(Ⅵ)-contaminated soil by alkali-activated ground granulated blast furnace slag
摘要
Abstract
Alkali-excited ground granulated blast furnace slag(GGBFS)can be used in solidification of contaminated soil as an alternative to cement(PC),and has the merits of low energy consumption and low carbon emission.At the same time,the sulfur contained in the GGBFS can reduce hexavalent chromium to trivalent chrome and therefore significantly improve the treat efficiency.Solidification/stabilization(S/S)of a Cr-contaminated soil with the total Cr content of 2000 mg/kg(including 1210 mg/kg Cr(Ⅵ))is carried out.The treatment by the alkali-excited GGBFS is compared with that by PC.The leaching toxicity,immobilization efficiency and unconfined compressive strength are analyzed to study the treatment effects.The pH,reduction efficiency,chemical morphology,mineral composition and microscopic images are analyzed to investigate the related mechanism.The results show that the leached Cr concentration after treated by the GGBFS is significantly lower than that of the PC.At a GGBFS dosage of 20%and a curing period of 28 d,the leached total Cr and Cr(Ⅵ)decrease to 2.12 and 1.09 mg/L,which meet the regulation limit for landfill disposal.The strength of the GGBFS-treated soil is obviously higher than that of the PC.The valence state analysis shows that S2-in the GGBFS can effectively reduce Cr(Ⅵ)to Cr(Ⅲ)with a reduction efficiency as high as 96.0%,which avoids the inhibition of Cr(Ⅵ)to the hydration process.The additional reduction agent is not needed when treating such a Cr-contaminated soil with the GGBFS.After the GGBFS treatment,more unstable Cr is transformed to stable forms,and the Cr mobility is significantly reduced.Also,more hydrated gels are generated for cementation of soil particles,resulting in better encapsulation effects and higher strength.This study provides a scientific basis for the S/S of Cr(Ⅵ)-contaminated soil using the GGBFS.关键词
粒化高炉矿渣/Cr(Ⅵ)污染土/固化/稳定化/浸出浓度/还原效率Key words
ground granulated blast furnace slag/Cr(Ⅵ)-contaminated soil/solidification/stabilization/leaching concentration/reduction efficiency分类
建筑与水利引用本文复制引用
张文杰,金典,郭兴璋,李西斌..碱激发高炉矿渣固化/稳定化Cr(Ⅵ)污染土试验研究[J].岩土工程学报,2025,47(1):57-64,8.基金项目
国家自然科学基金项目(52478353) （52478353）
