naa a22 4500 510752861 CHVBK 20180411083111.0 cr unu---uuuuu 180411e20131101xx s 000 0 eng 10.1007/s11270-013-1757-0 doi (NATIONALLICENCE)springer-10.1007/s11270-013-1757-0 Inhibition of Acid Mine Drainage from a Pyrite-rich Mining Waste Using Industrial By-products: Role of Neo-formed Phases [Elektronische Daten] [P. Sahoo, S. Tripathy, M. Panigrahi, Sk. Equeenuddin] In the present study, the potential use of the industrial waste residues, such as coal fly ash and clinker dust, was evaluated in inhibiting acid mine drainage generation from pyrite-rich wastes using non-saturated column experiments. Two columns (B and C) were filled with a mixture of industrial residues over pyrite-quartz sand (PS), while one column (A) used as the control was solely filled with PS. Artificial irrigation was maintained in each column by pouring Milli-Q water (pH 6.5). The leachate chemistry and the precipitation of neo-formed phases in the columns were examined. Based on the pH and concentration of SO4 2− in the effluent collected over a period of time, it can be inferred that pyrite dissolution was dominant in column A. In columns B and C, the addition of industrial waste produced a near neutral to alkaline leachate. At this pH, Fe released from pyrite oxidation was immediately depleted by precipitating into Fe-oxyhydroxide phases that likely coated the pyrite grains (termed as microencapsulation) which inhibited oxidation. This was supported from the scanning electron microscope observation and the geochemical modeling results. In addition, the precipitation of other neo-formed phases such as calcium carbonate and gypsum, along with the pozzolanic reactions of industrial wastes, possibly increased the cementation of fly ash particles leading to the development of a compact material, which prevented further oxidation by restricting infiltration and oxygen contact to the pyrite surface. This occurred best in column B; thus, it produced better quality of leachates than column C, though at the end both columns showed a significantly decreased concentration of Fe (up to 99.9%) and other metals such as Cu, Cr, Pb, Zn, and Mn (lower values than the WHO permissible limits of drinking water) compared to control. Springer Science+Business Media Dordrecht, 2013 Acid mine drainage nationallicence Fly ash nationallicence Pyrite oxidation nationallicence Secondary precipitate nationallicence Microencapsulation nationallicence Sahoo P. Vale Institute of Technology Sustainable Development, Boaventura da Silva, 66055-090, Belém, Pará, Brazil aut Tripathy S. Department of Geology & Geophysics, Indian Institute of Technology, 721302, Kharagpur, West Bengal, India aut Panigrahi M. Department of Geology & Geophysics, Indian Institute of Technology, 721302, Kharagpur, West Bengal, India aut Equeenuddin Sk Department of Mining Engineering, National Institute of Technology, 769008, Rourkela, Odisha, India aut Water, Air, & Soil Pollution Springer Netherlands 224/11(2013-11-01), 1-11 0049-6979 224:11<1 2013 224 11270 https://doi.org/10.1007/s11270-013-1757-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11270-013-1757-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sahoo P. Vale Institute of Technology Sustainable Development, Boaventura da Silva, 66055-090, Belém, Pará, Brazil aut NATIONALLICENCE 700 1- Tripathy S. Department of Geology & Geophysics, Indian Institute of Technology, 721302, Kharagpur, West Bengal, India aut NATIONALLICENCE 700 1- Panigrahi M. Department of Geology & Geophysics, Indian Institute of Technology, 721302, Kharagpur, West Bengal, India aut NATIONALLICENCE 700 1- Equeenuddin Sk Department of Mining Engineering, National Institute of Technology, 769008, Rourkela, Odisha, India aut NATIONALLICENCE 773 0- Water, Air, & Soil Pollution Springer Netherlands 224/11(2013-11-01), 1-11 0049-6979 224:11<1 2013 224 11270 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer