Acid mine drainage and its treatment Mpofu K.*, Mushiri S.*, Nyoni K.** *Scientific and Industrial Research and Development Centre (SIRDC), Great Zimbabwe University **Great Zimbabwe University, Faculty of Agriculture and Natural Sciences, P.O. Box 1235, Masvingo, Zimbabwe Online published on 5 June, 2014. Abstract This paper made an attempt to highlight what Acid Mine Drainage is as well as the possible management and control methods employed in the mining sector where AMD is a problem. Acid Mine Drainage is an environmental pollutant of major concern throughout the world. The mining sector is responsible for the contamination of the environment through its release. It is generated through the mining of sulphur-bearing ore deposits. This exposes sulphidic rocks to surface water and oxygen which accelerates oxidation, leaching and release of metals and generation of the Acid Mine Drainage. It is characterized by a pH of 2 or less, total dissolved solids (TDS) in the order of 4000-5000mg/l, high Fe content, high Al and Mn concentrations and a high sulphate content. In terms of management and control of AMD, the objective is to satisfy environmental requirements using the most cost-effective techniques. There are three key strategies in acid mine drainage management, namely: the control of acid generation process, control of acid migration and the collection and treatment of AMD. The paper also added a fourth one which has been shown to be effective in the management and control of AMD. This involves AMD treatment through co-disposal with Coal ash. Using this co-disposal method, most metals were removed by approximately 100% when the pH of minimum solubility of hydroxides was achieved. Sulphate removal was found to be approximately 80% due to gypsum precipitation. Top Keywords Acid Mine Drainage, Co-disposal, Sulphidic Rocks, Coal Ash, Neutralisation, Water Chemistry, Acid Migration. Top |