Study on Microbial Cure and Stabilization Effect and Mechanisms of Zinc-Contaminated Silt
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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。Abstract: 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 (CaCl2∶Urea) was 1∶2, and the curing age was 28 d.
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Key words:
- MICP /
- Zn-contaminated soil /
- cure effect /
- toxic leaching /
- microstructure
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[1] 杜延军, 金飞, 刘松玉, 等. 重金属工业污染场地固化/稳定处理研究进展[J]. 岩土力学, 2011, 32(1): 116-124. [2] 何稼, 楚剑, 刘汉龙, 等. 微生物岩土技术的研究进展[J]. 岩土工程学报, 2016, 38(4): 643-653. [3] 陈云敏, 施建勇, 朱伟, 等. 环境岩土工程研究综述[J]. 土木工程学报, 2012, 45(4): 165-182. [4] 钱春香, 王明明, 许燕波. 土壤重金属污染现状及微生物修复技术研究进展[J]. 东南大学学报(自然科学版), 2013, 43(3):669-674. [5] GAO Y F, MENG H, HE J, et al. Field trial on use of soybean crude extract for carbonate precipitation and wind erosion control of sandy soil[J]. Journal of Central South University, 2020, 27(11): 3320-3333. [6] CHEN H M, MIN F F, HU X, et al. Biochar assists phosphate solubilizing bacteria to resist combined Pb and Cd stress by promoting acid secretion and extracellular electron transfer[J/OL]. Journal of Hazardous Materials, 2023, 452[2023-03-19]. https://doi.org/10.1016/j.jhazmat.2023.131176. [7] 许朝阳, 张贺, 杨贺, 等. MICP技术对 Mn(Ⅱ)、Cr(Ⅵ)污染土壤的修复效果[J]. 扬州大学学报(自然科学版), 2020, 23(2): 73-78. [8] NASRIN J, ABDOLREZA A, HOSSEIN A A, et al. Removal of heavy metals Zinc, Lead, and Cadmium by biomineralization of urease-producing bacteria isolated from Iranian mine calcareous soils[J]. Journal of Soil Science and Plant Nutrition, 2020, 20(3): 206-219. [9] FANG L Y, NIU Q J, CHENG L, et al. Ca-mediated alleviation of Cd2+ induced toxicity and improved Cd2+ biomineralization by Sporosarcina pasteurii[J/OL]. Science of the Total Environment, 2021, 787[2023-03-19].https://doi.org/10.1016/j.scitotenv.2021.147627. [10] 李驰, 田蕾, 董彩环, 等. MICP技术联合多孔硅吸附材料对锌铅复合污染土固化/稳定化修复的试验研究[J]. 岩土力学, 2022, 43(2): 307-316. [11] 邵光辉, 戴浩然, 郭恒君. 微生物固化和稳定化铅污染粉土的强度与污染物浸出特性[J]. 林业工程学报, 2022, 7(5): 161-168. [12] 许朝阳, 杨贺, 黄建璋, 等. 生物修复Cu2+、Pb2+污染土的稳定性[J]. 工业建筑, 2018, 48(7): 33-37. [13] WEI M L, DU Y J, REDDY K R, et al. Effects of freeze-thaw on characteristics of new KMP binder stabilized Zn- and Pb-contaminated soils[J]. Environmental Science and Pollution Research International, 2015, 22:19473-19483. [14] 许朝阳, 柏庭春, 黄建璋, 等. 铁细菌修复锌污染土壤的试验研究[J]. 工业建筑, 2016, 46(6): 90-93. [15] JASON T D, MICHAEL B F, KLAUS N. Microbially induced cementation to control sand response to undrained shear[J/OL]. Journal of Geotechnical and Geoenvironmental Engineering, 2006, 132(11) [2023-03-19]. https://doi.org/10.1061/(ASCE)1090-0241(2006)132:11(1381). [16] 刘璐, 沈扬, 刘汉龙, 等. 微生物胶结在防治堤坝破坏中的应用研究[J]. 岩土力学, 2016, 37(12): 3410-3416. [17] ACHAL V, PAN X. Influence of calcium sources on microbially induced calcium carbonate precipitation by bacillus sp. CR2[J]. Applied Biochemistry and Biotechnology, 2014, 173(1):307-317. [18] 刘汉龙, 肖鹏, 肖杨, 等. 微生物岩土技术及其应用研究新进展[J]. 土木与环境工程学报(中英文), 2019, 41(1): 1-14. [19] RAMACHANDRAN S K, RAMAKRISHNAN V, BANG S S. Remediation of concrete using micro-organisms[J]. ACI Materials Journal, 2001, 98(1): 3-9. [20] WHIFFIN V S. Microbial CaCO3 precipitation for the production of biocement[D]. Perth: Murdoch University, 2004. [21] 马瑞男, 郭红仙, 程晓辉, 等. 微生物拌和加固钙质砂渗透特性试验研究[J]. 岩土力学, 2018, 39(增刊2): 217-223. [22] TESSIER A, CAMPBELL P, BISSON M. Sequential extraction procedure for the speciation of particulate trace metals[J]. Analytical Chemistry, 1979, 51(7): 844-851. [23] US Environmental Protection Agency(US EPA). Test methods for evaluating solid waste, physical/chemical methods. method 1311: toxicity characteristic leaching procedure:EPA SW-846[S]. Washington DC: US EPA, 1992. [24] 刘祖典, 李靖, 郭增玉, 等. 陕西关中黄土变形特性和变形参数的探讨[J]. 岩土工程学报, 1984, 6(3): 24-34. [25] 吴旭阳, 梁庆国, 牛富俊, 等. 黄土剪切应变硬化-软化分类试验研究[J]. 地下空间与工程学报, 2017, 13(6): 1457-1466. [26] NEMATI M, GREENE E A, VOORDOUW G. Permeability profile modification using bacterially formed calcium carbonate: comparison with enzymic option[J]. Process Biochemistry, 2005, 40(2): 925-933. [27] KUNST F, RAPOPORT G. Salt stress is an environmental signal affecting degradative enzyme synthesis in Bacillus subtilis[J]. Journal of Bacteriology, 1995, 177(9): 2403-2407. [28] XU G J, LI D W, JIAO B Q, et al. Biomineralization of a calcifying ureolytic bacterium Microbacterium sp. GM-1[J/OL]. Electronic Journal of Biotechnology, 2017, 25(25) [2023-03-19].https://doi.org/10.1016/J.EJBT.2016.10.008. [29] PAKBAZ M S, BEHZADIPOUR G R. Evaluation of shear strength parameters of sandy soils upon microbial treatment[J]. Geomicrobiology Journal, 2018, 35(8): 721-726. [30] QABANY A A, SOGA K, SANTAMARINA C. Factors affecting efficiency of microbially induced calcite precipitation[J]. Journal of Geotechnical & Geoenvironmental Engineering, 2012, 138(8): 992-1001. [31] 彭劼, 温智力, 刘志明, 等. 微生物诱导碳酸钙沉积加固有机质黏土的试验研究[J]. 岩土工程学报, 2019, 41(4): 733-740. [32] 刘清, 王子健, 汤鸿霄. 重金属形态与生物毒性及生物有效性关系的研究进展[J]. 环境科学, 1996, 17(1): 89-92. [33] 尹黎阳, 唐朝生, 谢约翰, 等. 微生物矿化作用改善岩土材料性能的影响因素[J]. 岩土力学, 2019, 40(7): 2525-2546. [34] MORTENSEN B M, HABER M J, DEJONG J T. Effects of environmental factors on microbial induced calcium carbonate precipitation[J]. Journal of Applied Microbiology, 2011, 111(2): 338-349. [35] 邵光辉, 尤婷, 赵志峰, 等. 微生物注浆固化粉土的微观结构与作用机理[J]. 南京林业大学学报(自然科学版), 2017, 41(2): 129-135. [36] AL QABANY A, SOGA K, SANTAMARINA C. Factors affecting efficiency of microbially induced calcite precipitation[J]. Journal of Geotechnical & Geoenvironmental Engineering, 2012, 138(8): 992-1001. [37] 王绪民, 王铖, 崔芮. 微生物在不同营养盐环境下矿化产物研究[J].工业建筑, 2019, 49(10): 208-212. [38] 刘汉龙, 赵常, 肖杨. 微生物矿化反应原理、沉积与破坏机制及理论:研究进展与挑战[J/OL]. 岩土工程学报, 2023[2023-03-19].https://doi.org/10.11779/CJGE20230004.
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