微生物介导碳酸盐/磷酸盐沉淀技术修复铅(Pb)污染地下水和黄土的影响机理研究  

Immobilization of lead contaminated groundwater and loess soil using microbial-induced carbonate precipitation or phosphate precipitation and exploration of its influencing mechanism

作　　者：秦鹏 郑文杰 薛中飞 王琳[1,2] 吕鑫江[1,2] 何文杰 Qin Peng;Cheng Wen-chieh;Xue Zhongfei;Wang Lin;Lu Xinjiang;He Wenjie(School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]西安建筑科技大学陕西省岩土与地下空间工程重点实验室,陕西西安710055

出　　处：《土木工程学报》2025年第1期101-110,125,共11页China Civil Engineering Journal

基　　金：创新人才推进计划-科技创新团队(2020TD-005);中共中组部“国家海外高层次人才引进计划”青年项目(2019)。

摘　　要：中国西北金属矿藏开发利用虽加速当地经济发展,然而不当的含铅(Pb)废水处置将导致场地污染,对周边生态环境和人类健康造成极大威胁。该研究分别探究了微生物介导碳酸盐沉淀(MICP)技术和微生物介导磷酸盐沉淀(MIPP)技术修复铅污染地下水和黄土的潜力,并对二者修复效率和内在影响机理进行深入分析。试验结果发现,巴氏芽孢八叠球菌在酸性条件解脲能力较差导致尿素水解程度较低,得到的修复效率仅为10.82%,且矿化产物碳酸铅(PbCO3)和碱式碳酸铅(Pb3(CO3)2(OH)2)化学稳定性低;而巨大芽孢杆菌在酸性条件下表现出较强的解磷能力,仍可以得到80%以上的修复效率,且矿化产物磷氯铅矿(Pb5(PO4)3Cl)化学稳定性高,微观试验识别的矿化产物是以细菌为成核位点的共沉淀结构(Ca2Pb3(PO4)3Cl矿物与磷酸盐矿物),降低了Pb2+再次迁移扩散的概率。铅污染黄土修复试验中,巨大芽孢杆菌得到修复效率较高且赋存形态主要为铁锰氧化态Pb,相较巴氏芽孢八叠球菌修复后的碳酸盐结合态Pb具有更高的化学稳定性和更低的生态毒性。Although the exploitations of metal deposits in northwest China have accelerated economic development,improper disposal of lead(Pb)contained wastewater may lead to site pollution,posing the great threat to the ecological environment and human health.In this study,the immobilization experiments in lead contaminated groundwater and loess soil of microbial-induced carbonate precipitation(MICP)andmicrobial-inducedphosphate precipitation(MIPP)were investigated.The results show that the urea-releasing ability of Sporosarcina pasteuri may result in a lower degree of urea hydrolysis under acidic conditions,the immobilization efficiency of Pb is only 10.82%,and the mineralization products PbCO,and Pb,(CO,)2(OH)2 have low chemical stability;while Bacillus megaterium has great potential for phosphate-releasing ability in acidic condition,achieving the immobilization efficiency of over 80%.In addition,the mineralized product Pb,(PO4)3 Cl has high chemical stability,and the mineralized product identified by the microscopic test is a co-precipitation(Ca,Pb;(PO4),Cl and Phosphate mineral)structure with bacteria as the nucleation site,reducing the probability of Pb2+re-migrating and diffusing to the environment.The immobilization experiments in lead contaminated loess soil show that Bacillus megaterium has a high immobilization efficiency and the occurrence form of lead is Fe-Mn oxides bound.Compared with the carbonate bound,it has higher chemical stability and lower ecotoxicity.

关 键 词：微生物介导碳酸盐沉淀(MICP) 微生物介导磷酸盐沉淀(MIPP) 铅污染地下水 铅污染黄土 修复效率 

分 类 号：X52[环境科学与工程—环境工程]