School of Resource and Environmental Engineering, Hefei University of Technology, Hefei 230009, China.
State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Molecules. 2022 Jun 4;27(11):3608. doi: 10.3390/molecules27113608.
Tailing sand contains a large number of heavy metals and sulfides that are prone to forming acid mine drainage (AMD), which pollutes the surrounding surface environment and groundwater resources and damages the ecological environment. Microbially induced calcium carbonate precipitation (MICP) technology can biocement heavy metals and sulfides in tailing sand and prevent pollution via source control. In this study, through an unconfined compressive strength test, permeability test, and toxic leaching test (TCLP), the curing effect of MICP was investigated in the laboratory and the effect of grouting rounds on curing was also analyzed. In addition, the curing mechanism of MICP was studied by means of Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction spectroscopy (XRD), and scanning electron microscopy (SEM). The experimental results showed that MICP could induce calcium carbonate precipitation through relatively complex biochemical and physicochemical reactions to achieve the immobilization of heavy metals and sulfides and significantly reduce the impact of tailing sand on the surrounding environment.
尾矿砂中含有大量的重金属和硫化物，容易形成酸性矿山排水（AMD），污染周围的地表环境和地下水资源，破坏生态环境。微生物诱导碳酸钙沉淀（MICP）技术可以通过生物固持作用将尾矿砂中的重金属和硫化物固化，从而达到源头控制污染的目的。本研究通过无侧限抗压强度试验、渗透试验和毒性浸出试验（TCLP），在实验室中研究了 MICP 的固化效果，并分析了注浆圈对固化的影响。此外，还通过傅里叶变换红外光谱（FTIR）、热重分析（TGA）、X 射线衍射光谱（XRD）和扫描电子显微镜（SEM）研究了 MICP 的固化机制。实验结果表明，MICP 可以通过相对复杂的生化和物理化学反应诱导碳酸钙沉淀，从而实现重金属和硫化物的固定，并显著降低尾矿砂对周围环境的影响。
