College of Mining, Liaoning Technical University, Fuxin, China.
College of Science, Liaoning Technical University, Fuxin, China.
PLoS One. 2022 Jan 19;17(1):e0261823. doi: 10.1371/journal.pone.0261823. eCollection 2022.
The problems of acid mine drainage (AMD) in coal mine acidic wastewaters arise from a range of sources, including severe pollution with heavy metals and SO42- and difficulties during treatment. Based on the ability of Maifan stone to adsorb heavy metals and the dissimilatory reduction of SO42- by sulfate-reducing bacteria (SRB), Maifan stone-sulfate-reducing bacterium-immobilized particles were prepared via immobilization techniques using Shandong Maifan stone as the experimental material. The effects of Maifan stones containing SRB on mitigating AMD were investigated by constructing Dynamic Column 1 with Maifan stone-sulfate-reducing bacterium-immobilized particles and by constructing Dynamic Column 2 with SRB mixed with Maifan stones. By the use of adsorption isotherms, adsorption kinetics, a reduction kinetics model and X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies, the mechanism by which Maifan stone-sulfate-reducing bacterium-immobilized particles mitigate AMD was revealed. The results showed that the total effect of Maifan stone-sulfate-reducing bacterium-immobilized particles on AMD was better than that of biological Maifan stone carriers. The highest rates for the removal of Fe2+, Mn2+, and SO42- in AMD were 90.51%, 85.75% and 93.61%, respectively, and the pH value of the wastewater increased from 4.08 to 7.64. The isotherms for the adsorption of Fe2+ and Mn2+ on Maifan stone-sulfate-reducing bacterium-immobilized particles conformed to the output of the Langmuir model. The adsorption kinetics were in accordance with Lagergren first-order kinetics, and the kinetics for the reduction of SO42- conformed to those of a first-order reaction model.
煤矿酸性废水中的酸性矿山排水（AMD）问题源于多种来源，包括重金属和 SO42- 的严重污染以及处理困难。基于麦饭石吸附重金属的能力和硫酸盐还原菌（SRB）对 SO42- 的异化还原能力，以山东麦饭石为实验材料，采用固定化技术制备了麦饭石-硫酸盐还原菌-固定化颗粒。通过构建填充有麦饭石-硫酸盐还原菌-固定化颗粒的动态柱 1 和填充有混合麦饭石的 SRB 的动态柱 2，研究了含 SRB 的麦饭石对 AMD 的缓解作用。通过吸附等温线、吸附动力学、还原动力学模型以及 X 射线衍射（XRD）和扫描电子显微镜（SEM）研究，揭示了麦饭石-硫酸盐还原菌-固定化颗粒缓解 AMD 的机制。结果表明，麦饭石-硫酸盐还原菌-固定化颗粒对 AMD 的总效果优于生物麦饭石载体。AMD 中 Fe2+、Mn2+和 SO42-的去除率最高分别达到 90.51%、85.75%和 93.61%，废水的 pH 值从 4.08 增加到 7.64。Fe2+和 Mn2+在麦饭石-硫酸盐还原菌-固定化颗粒上的吸附等温线符合朗缪尔模型的输出。吸附动力学符合 Lagergren 一级动力学，SO42-的还原动力学符合一级反应模型。
