Improving Acid Mine Drainage Treatment through Electrocoagulation: Effect of Time, Electrode Distance, and Electrode Types

¹ Department of Chemical Engineering, Faculty of Engineering, Universitas Syiah Kuala, Jalan Tgk. Syech Abdurrauf As Singkili, No. 7, Darussalam, Banda Aceh, 23111, Indonesia
² Department of Mining Engineering, School of Earth Engineering, Faculty of Engineering, Universitas Syiah Kuala, Jalan Tgk. Syech Abdurrauf As Singkili, No. 7, Darussalam, Banda Aceh, 23111, Indonesia
³ Western Australia School of Mines, Minerals Energy and Chemical Engineering, Curtin University, 95 Egan Street, Kalgoorlie, Western Australia, 6430, Australia

^* Corresponding author: izzanaslam@usk.ac.id

Abstract

This study explores the feasibility of employing electrocoagulation technology to manage Acid Mine Drainage (AMD) wastewater, focusing on reducing heavy metal concentrations, particularly iron (Fe) and manganese (Mn). Samples of AMD liquid waste from PT Lhoong Setia Mining in Aceh Province, Indonesia, underwent electrocoagulation using Al-Zn and Al-Fe electrodes with Direct Current (DC). The investigation considered various parameters, including contact time (ranging from 0 to 45 minutes), electrode distance (2, 2.5, and 3 cm), and electrode type (Al-Fe and Al-Zn). The study revealed that prolonged electrocoagulation increased the reduction of Fe and Mn metals due to enhanced Al(OH)₃ formation. While Al-Zn electrodes exhibited rapid coagulant formation initially, Al-Fe electrodes sustained effectiveness throughout the process. Optimal reduction of Fe and Mn concentrations occurred at different electrode distances, emphasizing the critical role of spacing in electrocoagulation efficiency. Furthermore, the electrocoagulation process successfully elevated pH levels within acceptable limits and effectively reduced Total Suspended Solids (TSS) in AMD waste, aligning with regulatory standards. This research underscores the potential for electrocoagulation as a viable technology for mitigating the environmental impact of AMD and addresses knowledge gaps related to efficient pollutant removal in mining wastewater treatment. Future studies should explore parameter optimization and consider transitioning to continuous operation for increased effectiveness, particularly in remote mining locations.