IARJSET ISSN (Online) 2393-8021 ISSN (Print) 2394-1588 International Advanced Research Journal in Science, Engineering and Technology ISO 3297:2007 Certified Vol. 4, Issue 5, May 2017 Copyright to IARJSET DOI10.17148/IARJSET.2017.4525 131 Overview of Active and Passive Systems for Treating Acid Mine Drainage Vikram Seervi 1 , H.L. Yadav 2 , S.K. Srivastav 3 , A. Jamal 4 M Tech, Student, Department of Mining Engineering, Indian Institute of Technology, (BHU) Varanasi, India 1, 3 Research Scholar, Department of Mining Engineering, Indian Institute of Technology, (BHU) Varanasi, India 2 Professor, Department of Mining Engineering, Indian Institute of Technology, (BHU) Varanasi, India 4 Abstract: Acid mine drainage is among one of the qualitative pollution created mainly by mining activities. Water drained from active or abandoned mine workings is often indicated by low pH (pH value less than 5.6) with high concentrations of heavy iron and metals sulfate. This water is commonly referred as AMD. Acid mine drainage (AMD) is known to be one of the most severe environmental problem throughout the world in the mining affecting the environment as well as the economics of metal and coal mining operations. Acid mine drainage is also called as "acid rock drainage." This review describes the sources of AMD, pollutions created by AMD and also summarizes the method and application of active and passive techniques for treatment of AMD. Keywords: Sources of AMD active and passive treatment technology, environmental, chemical and biological treatment, wetlands. I. INTRODUCTION The purpose of mining operations is to full fill the demand for metals and coal resources to support the industrial development for improving the quality of life of the population, as these metals and coal resources are used as raw materials in agriculture, food, construction, energy, transport, and technology in our daily lives, and are vital for technological, economic and social development [1]. However, the mining operations create several environmental problems, and one of them is Acid mine drainage (AMD). AMD generated from the mining of metal or coal contains high acidity [2,3](i.e., low pH formed by sulfide oxidation) and many heavy and toxic metals which have known to be adverse effects on aquatic life and human beings[4].This paper describes a concise review of sources AMD in mines, afterward a brief of treatment methods. Terminology and technical descriptions in this article have been kept simple so as to provide a review that can be used by the reader. For more technical details, please refer to the specific research articles. II. SOURCES OF AMD The main sources of AMD are sulfide minerals which one present in sulfide form in coal and metal ores are categorized as primary and secondary sources are as follows: Primary sources are Mine rock dumps, tailings ponds, Underground and open pit mine workings, underground pumped water, diffuse seeps from replaced overburden in rehabilitated areas, construction rock used in railway, haulage roadways, dams, etc. Secondary sources are Mineral processing sludge pounds, rock chips, concentrated load-out, stockpiles, concentrate spills along roads, emergency ponds [5]. III. TREATMENT TECHNOLOGIES FOR AMD Numerous of the method have been used worldwide for dealing with AMD. These technologies use one or a combination of chemical, physical and biological processes. Treatment of AMD is broadly categorized in active and passive treatment. Active treatment -Mechanical addition of alkaline chemicals to the effluent is used pH and precipitate metals. Passive treatment - Naturally occurring chemical and biological reactions occur in a controlled microbiological – chemical reactor without powered mechanical assistance (most of the time). The active treatment system requires more unit processes, and it is more complicated, and higher process costs compared to the easiest and uncomplicated passive treatment system. Its overall operating cost is very low as compare to another treatment process[3].