Bench-scale microbial remediation of the model acid mine drainage: effects of nutrients and microbes on the source bioremediation

In this work, a bench-scale microbial remediation system was
established by supplemented
nutrients, sulfate reducing bacteria and iron reducing bacteria
to inhibit key factors (iron oxidizing bacteria and oxidation reduction potential)
during the formation of acid mine drainage. The results indicated sodium
lactate could inhibit the growth of A. ferrooxidans and their ability of
oxidizing ferrous ion, could alleviate but not prevent the pyrite oxidizing
process. Organic nutrients prevented pyrite oxidation effectively by the
adjustment of microbial community. Sulfate reducing
bacteria adapted to the remediate environment and improved
physicochemical index of group 1. Sulfate reducing bacteria and nutrients are the key factor for bioremediation.

本研究构建了一套实验室规模（bench-scale）的微生物修复体系，通过补加营养物质、硫酸盐还原菌（Sulfate Reducing Bacteria, SRB）与铁还原菌（Iron Reducing Bacteria, IRB），以抑制酸性矿山排水（Acid Mine Drainage, AMD）形成过程中的关键调控因子——铁氧化菌（Iron Oxidizing Bacteria, IOB）与氧化还原电位（Oxidation Reduction Potential, ORP）。研究结果显示，乳酸钠（sodium lactate）可抑制氧化亚铁硫杆菌（Acidithiobacillus ferrooxidans, A. ferrooxidans）的生长及其氧化亚铁离子（ferrous ion）的能力，能够缓解但无法完全阻断黄铁矿（pyrite）的氧化进程。有机营养物质可通过调控微生物群落（microbial community）结构，高效抑制黄铁矿的氧化过程。硫酸盐还原菌可适应修复环境，并提升1号试验组的理化指标（physicochemical index）。硫酸盐还原菌与营养物质是该生物修复（bioremediation）过程的核心调控因子。