Ren Shuang, Fan Xiao, Fang Zhijin, Zhu Mingtan, Liu Guo, Tang Jie, Wang Peng
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu 610059, PR China; Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, Ministry of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, China; College of Environment Civil Engineering, Chengdu University of Technology, Chengdu 610059, PR China.
College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China; Sichuan Shudu Geological Engineering Survey Co., Ltd, Chengdu 610100, PR China.
J Hazard Mater. 2025 Aug 15;494:138710. doi: 10.1016/j.jhazmat.2025.138710. Epub 2025 May 27.
The acidic environment and lack of carbon sources in acid mine drainage (AMD) limit the effectiveness of sulfate-reducing bacteria (SRB) in its treatment. The use of urease-producing bacteria (UPB) to hydrolyze urea and drive SRB to treat AMD addresses these two key limitations. Based on the pollution characteristics of AMD from an abandoned sulfur iron mine in Southwest China, this study investigates the feasibility of the combined UPB-SRB treatment for simulated AMD, explores the synergistic mechanism, and evaluates the practical application of this synergy in the treatment of real AMD. The UPB-SRB combination outperforms the individual use of UPB or SRB. When UPB neutralized the pH of simulated AMD from 2 to 5, the highest cost-effectiveness was observed: the solution's pH increased to 7.2, with removal efficiencies for SO, Fe, Fe, and Mn reaching 89.18 %, 95.59 %, 95.81 %, and 88.2 %, respectively. The reaction products of the UPB-SRB synergy included FeOOH, FeO, FeS, Fe, and MnS. UPB utilized ammonia generated from urea hydrolysis to improve the acidic environment, while its metabolic by-products, including amino acids, organic acids, alcohols, and vitamin B, provided carbon and nitrogen sources for SRB. In the treatment of real AMD, the synergistic effect of UPB-SRB achieved removal efficiencies of 96.89 % for SO, 100 % for Fe, and 99.89 % for Mn, and raised the pH from 2 to 8. The treated AMD showed no bio-toxicity or potential risks and demonstrated agricultural reuse potential. By replacing traditional carbon/nitrogen sources with urea-containing wastewater, the combined use of UPB and SRB provides an efficient, safe, and cost-effective solution for AMD disposal, offering a novel approach to optimizing SRB-based AMD treatment and urea wastewater resource utilization.
酸性矿山排水（AMD）中的酸性环境和碳源缺乏限制了硫酸盐还原菌（SRB）在其处理中的有效性。利用产脲酶细菌（UPB）水解尿素并驱动SRB来处理AMD解决了这两个关键限制。基于中国西南部一个废弃硫铁矿的AMD污染特征，本研究调查了UPB-SRB联合处理模拟AMD的可行性，探索了协同机制，并评估了这种协同作用在实际AMD处理中的实际应用。UPB-SRB组合的效果优于单独使用UPB或SRB。当UPB将模拟AMD的pH从2中和到5时，观察到最高的成本效益：溶液的pH升至7.2，SO、Fe、Fe和Mn的去除效率分别达到89.18%、95.59%、95.81%和88.2%。UPB-SRB协同作用的反应产物包括FeOOH、FeO、FeS、Fe和MnS。UPB利用尿素水解产生的氨来改善酸性环境，而其代谢副产物，包括氨基酸、有机酸、醇类和维生素B，为SRB提供了碳源和氮源。在实际AMD处理中，UPB-SRB的协同作用使SO的去除效率达到96.89%，Fe的去除效率达到100%，Mn的去除效率达到99.89%，并将pH从2提高到8。处理后的AMD没有生物毒性或潜在风险，并显示出农业再利用潜力。通过用含尿素废水替代传统的碳/氮源，UPB和SRB的联合使用为AMD处理提供了一种高效、安全且具有成本效益的解决方案，为优化基于SRB的AMD处理和尿素废水资源利用提供了一种新方法。
