Review of the recent advances in the prevention, treatment, and resource recovery of acid mine wastewater discharged in coal mines

Coal mines discharge low-pH acid mine drainage (AMD), which contains a variety of heavy metals and sulfates that are extremely polluting and corrosive, posing a continuous threat to the ecological environment and human health. Hence, the effective management of AMD has become a global concern. By reviewing the formation mechanism, hazards, and composition characteristics of acid mine wastewater, this study analyzed the control methods and treatment technologies that can be used for source prevention and control and finally effective governance. The reaction mechanism and advantages and disadvantages of several treatment techniques, including the commonly used active and passive treatments, were discussed in depth, and the applicability of the various technologies was evaluated. Our findings showed that solely relying on a single technology cannot meet the emission standards and industrial requirements for the recycling of resources including water resources, valuable metals, and rare earth elements. According to the principle of complementary advantages, an improved treatment method involving a collaborative technology was proposed to improve the removal efficiency of pollutants and resource recovery of valuable metals, so as to realize a sustainable treatment of AMD. The predicted synergistic technology will be the main direction for future exploration and development.

Automated summary

Coal mines discharge acid mine drainage (AMD) containing heavy metals and sulfates, posing a serious threat to the environment and human health. This study reviewed the formation mechanism and hazards of AMD and analyzed control and treatment methods. The limitations of single technologies were identified, and an improved treatment method involving collaborative technologies was proposed to achieve sustainable AMD treatment.