锌污染粉土微生物固化和稳定效果及其机理研究  

Study on Microbial Cure and Stabilization Effect and Mechanisms of Zinc-Contaminated Silt

作　　者：邢玮 周峰 朱锐 陈廷柱 XING Wei;ZHOU Feng;ZHU Rui;CHEN Tingzhu(College of Transportation Engineering,Nanjing Tech University,Nanjing 211816,China;Key Laboratory of Geohazard Fujian Province,Fuzhou 350002,China;National Key Laboratory of Water Disaster Prevention,Nanjing Hydaulic Research Institute,Nanjing 210029,China;Nanjing Jiangbei Construction Engineering Co.,Ltd.,Nanjing 210031,China)

机构地区：[1]南京工业大学交通运输工程学院,南京211816 [2]福建省地质灾害重点实验室,福州350002 [3]南京水利科学研究院水灾害防御全国重点实验室,南京210029 [4]南京江北公用建筑工程有限公司,南京210031

出　　处：《工业建筑》2024年第9期32-42,共11页Industrial Construction

基　　金：江苏省自然科学基金项目(BK20220356);福建省地质灾害重点实验室开放基金资助项目(FJKLGH2023K005);一带一路与可持续发展科技基金资助项目(2023nkms05);江苏省地质局科技创新项目(2023KY03);新疆维吾尔自治区中央引导地方科技发展资金项目(ZYYD2024CG20)。

摘　　要：随着工业的快速发展,以锌为代表的重金属污染土问题日益突出,研究锌污染粉土处治方法和固化效果具有重要意义。基于微生物诱导碳酸钙沉淀(MICP)技术,开展了一系列微生物加固锌污染粉土室内试验,从微观结构演化角度揭示微生物加固锌污染粉土的作用机理。结果表明:微生物矿化作用显著提升了锌污染粉土的力学性能,且可使锌污染粉土的渗透系数降低一个数量级,锌离子浸出浓度明显降低,可交换态锌含量占比大幅减少,原因主要在于微生物矿化过程可生成具有胶结特性的方解石晶体,锌离子被固定并转化为碳酸锌,使得微生物在加固锌污染粉土的同时实现污染物控制和强度提升的双重目标。当胶结液浓度为1 mol/L、胶结液配比(氯化钙∶尿素)为1∶2、养护龄期为28 d时,微生物固化和稳定化锌污染粉土的作用效果最为显著。With the rapid development of industry,the problem of soil contaminated by heavy metals,represented by Zn,has been becoming more and more prominent,and it is important to study the treatment methods and cured effects on Zn-contaminated silt.Based on the microbial induced calcium carbonate precipitation(MICP)technique,a series of indoor experiments on microbial-cemented Zn-contaminated soil were conducted to reveal the mechanism of microbial cementation of Zn-contaminated soil from the perspective of microstructural evolution.The results showed that microbial mineralization significantly improved the mechanical properties of Zn-contaminated soil,and reduced the permeability coefficient of Zn-contaminated soil by an order of magnitude,significantly reduced the leaching concentration of Zn ions and the percentage of the exchangeable Zn content.It mainly might produce calcite crystals with colloidal properties during the microbial mineralization process,and zinc ions were fixed and tranfered to zinc carbonate,which made the microbial-cemented Zn-contaminated soil achieve the dual objectives of contaminant control and strength enhancement simultaneously.The microbial cure and stabilization of Zn-contaminated silt were most effective when the cementitious solution concentration was 1 mol/L,the cementitious solution ratio(CaCl 2∶Urea)was 1∶2,and the curing age was 28 d.

关 键 词：微生物矿化作用 锌污染土 固化效果 毒性浸出 微观结构 

分 类 号：X53[环境科学与工程—环境工程] TU472[建筑科学—结构工程]