工程地质学报2025，Vol.33Issue(6)：2095-2107,13.DOI:10.13544/j.cnki.jeg.2025-0295
不同胶结液驱动解磷微生物固化/稳定化重金属污染土力学特性研究
STUDY ON THE MECHANICAL PROPERTIES OF HEAVY METAL CON-TAMINATED SOIL SOLIDIFIED/STABILIZED BY PHOSPHATE-SOLUBI-LIZING MICROORGANISMS DRIVEN BY DIFFERENT CEMENTING FLUIDS
摘要
Abstract
Heavy metal contamination in soils,particularly Pb2+pollution,presents significant environmental and geotechnical concerns.This study evaluates the effectiveness of microorganism-induced phosphate precipitation(MIPP)for stabilizing lead-contaminated soils and compares the performance of different cementing solutions in enhancing mechanical properties and immobilizing lead.Sodium glycerophosphate(SGP)was used as the phosphorus source,with MgCl2(S-Mg group)and CaCl2(S-Ca group)introduced as auxiliary cementing agents.A series of laboratory tests-including unconfined compressive strength(UCS),direct shear tests,and toxicity characteristic leaching procedure(TCLP)analyses-were conducted under varying curing times(3,7,14,and 28 days)and Pb2+concentrations.The underlying mechanisms were further examined based on microbial activity,precipitation behavior,and mineral phase formation.The results indicate that MIPP treatment significantly improved the UCS and shear strength of Pb-contaminated soils,with the S-Ca group showing the most notable enhancement.After 14 days of curing,the peak UCS of the S-Ca group increased by up to 19.88％compared to other groups,while its peak shear strength rose by 36.36％.TCLP analyses confirmed that Pb2+concentrations in leachates from S-Ca-treated soils remained below 0.1 mg·L-1,complying with regulatory standards.Mechanistic investigations revealed that Ca2+addition alleviated the toxic effects of Pb2+on bacterial activity and promoted the formation of stable phosphate minerals,such as Ca2Pb3(PO4)3C1,thereby improving both soil structure and long-term stability.MIPP proves to be an effective and sustainable technique for stabilizing Pb-contaminated soils,enhancing mechanical strength while effectively controlling Pb2+leaching.Among the tested cementing solutions,the CaCl2-based system(S-Ca group)achieved an optimal balance between performance and cost-effectiveness,demonstrating strong potential for practical application in heavy metal-contaminated soil remediation.关键词
微生物矿化/MIPP/Pb2+污染土/强度特性Key words
Microbial mineralization/MIPP/Pb2+contaminated soil/Strength characteristics分类
资源环境引用本文复制引用
宋宇,陈玉洁,陈凯斌,江嘉辉,杨承琨,张铭致..不同胶结液驱动解磷微生物固化/稳定化重金属污染土力学特性研究[J].工程地质学报,2025,33(6):2095-2107,13.基金项目
国家自然科学基金项目(资助号:42262030),广西自然科学基金项目(资助号:2025GXNSFA069153),河南省科技研发计划联合基金项目(资助号:25208105).This research is supported by the National Natural Science Foundation of China(Grant No.42262030),the National Natural Science Foundation of Guangxi(Grant No.2025GXNSFA069153)and Henan Science and Technology R&D Program Joint Fund(Grant No.25208105). （资助号:42262030）
