Dong Yanrong, Gao Ziqing, Di Junzhen, Wang Dong, Yang Zhenhua, Guo Xuying, Zhu Xiaotong
College of Civil Engineering, Liaoning Technical University, Fuxin, China.
School of Mining, Liaoning Technical University, Fuxin, China.
Front Microbiol. 2024 Mar 28;15:1352430. doi: 10.3389/fmicb.2024.1352430. eCollection 2024.
In view of water and soil getting polluted by Pb(II), Zn(II), and other heavy metals in tailings and acid mine drainage (AMD), we explored the removal effect of sulfate-reducing bacteria (SRB) on Pb(II), Zn(II), and other pollutants in solution and tailings based on the microbial treatment technology. We used the scanning electron microscope-energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), and X-ray fluorescence (XRF), to reveal the mechanism of SRB treatment of tailings. The results showed that SRB had a strong removal capacity for Zn(II) at 0-40 mg/L; however, Zn(II) at 60-100 mg/L inhibited the growth of SRB. Similarly, SRB exhibited a very strong ability to remove Pb(II) from the solution. At a Pb(II) concentration of 10-50 mg/L, its removal percentage by SRB was 100%. SRB treatment could effectively immobilize the pollutants leached from the tailings. With an increase in the amount of tailings added to each layer, the ability of SRB to treat the pollutants diminished. When 1 cm of tailingssand was added to each layer, SRB had the best effect on tailing sand treatment. After treatment, the immobilization rates of , Fe(III), Mn(II), Pb(II), Zn(II), Cu(II), and total Cr in the leachate of #1 tailing sand were 95.44%, 100%, 90.88%, 100%, 96.20%, 86.23%, and 93.34%, respectively. After the tailings were treated by SRB, although the tailings solidified into a cohesive mass from loose granular particles, their mechanical strength was <0.2 MPa. and played the predominant roles in treating tailings by mixing SRB. The S and carbonate produced by mixing SRB during the treatment of tailings could metabolize sulfate by combining with the heavy metal ions released by the tailings to form FeS, MnS, ZnS, CuS, PbS, CrS, CaCO, MnCO, and other precipitated particles. These particles were attached to the surface of the tailings, reducing the environmental pollution of the tailings in the water and soil around the mining area.
鉴于尾矿和酸性矿山排水（AMD）中铅（II）、锌（II）等重金属对水土造成污染，我们基于微生物处理技术，探究了硫酸盐还原菌（SRB）对溶液和尾矿中铅（II）、锌（II）及其他污染物的去除效果。我们使用扫描电子显微镜-能谱仪（SEM-EDS）、X射线衍射仪（XRD）和X射线荧光光谱仪（XRF）来揭示SRB处理尾矿的机制。结果表明，SRB对0-40mg/L的锌（II）具有较强的去除能力；然而，60-100mg/L的锌（II）会抑制SRB的生长。同样，SRB对溶液中的铅（II）也表现出很强的去除能力。在铅（II）浓度为10-50mg/L时，SRB对其去除率达100%。SRB处理可有效固定尾矿中浸出的污染物。随着每层添加尾矿量的增加，SRB处理污染物的能力减弱。当每层添加1cm尾矿砂时，SRB对尾矿砂的处理效果最佳。处理后，1#尾矿砂渗滤液中Fe（III）、Mn（II）、Pb（II）、Zn（II）、Cu（II）和总Cr的固定率分别为95.44%、100%、90.88%、100%、96.20%、86.23%和93.34%。尾矿经SRB处理后，虽从松散颗粒固化成有粘性的团块，但其机械强度<0.2MPa。SRB混合处理尾矿时，S和碳酸盐起主要作用。SRB处理尾矿过程中产生的S和碳酸盐可通过与尾矿释放的重金属离子结合代谢硫酸盐，形成FeS、MnS、ZnS、CuS、PbS、CrS、CaCO、MnCO等沉淀颗粒。这些颗粒附着在尾矿表面，减少了矿区周边水土中尾矿对环境的污染。
