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Potgieter-Vermaak, S. S., Potgieter, J. H., Monama, P., & Van Grieken, R. (2006). Comparison of limestone, dolomite and fly ash as pre-treatment agents for acid mine drainage. Minerals Engineering, 19(5), 454–462.
Abstract: The physical, chemical and biological nature of Vaal Dam water, the main source of water in Gauteng, South Africa, is often affected by underground water pollution (acid mine water) and industrial effluents. The ecological significance and detrimental effects necessitate investigations into treating the water prior to discharge into public streams. Although several acid mine water treatment techniques and methods exist, they all have certain disadvantages. Lime treatment is the most common approach. In this investigation, limestone, dolomite and fly ash were selected as pre-treatment agents based on their low cost. Simulated acid mine water containing these agents was tested using a Jar Test apparatus. Samples were analyzed before and after treatment for pH, ferrous, ferric, calcium, magnesium and sulphate ions. The study demonstrated that the quality of the water improved with an increase in the amount and surface area of the raw material dosed and an increase in contact time. It was also influenced by the chemical composition of the acid mine water and aeration. Chemical cost savings of 38% are achieved when lime is replaced with limestone, and cost savings of 23% and 48% can be accomplished when limestone is substituted with dolomite and fly ash respectively. This could result in significant savings to the gold and coal mining industries, and could lead to a mutual benefit/gain between industrialists/polluters and the public.
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Akcil, A., & Koldas, S. (2006). Acid Mine Drainage (AMD): causes, treatment and case studies. J. Cleaner Prod., 14(12-13), 1139–1145.
Abstract: This paper describes Acid Mine Drainage (AMD) generation and its associated technical issues. As AMD is recognized as one of the more serious environmental problems in the mining industry, its causes, prediction and treatment have become the focus of a number of research initiatives commissioned by governments, the mining industry, universities and research establishments, with additional inputs from the general public and environmental groups. In industry, contamination from AMD is associated with construction, civil engineering mining and quarrying activities. Its environmental impact, however, can be minimized at three basic levels: through primary prevention of the acid-generating process; secondary control, which involves deployment of acid drainage migration prevention measures; and tertiary control, or the collection and treatment of effluent.
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Landers, J. (2006). Bioremediation method could cut cost of treating acid rock drainage. Civil Engineering, 76(7), 30–31.
Abstract: The Gilt Edge Mine in South Dakota's Lawrence County was a gold mine that was abandoned later when its recent owner went bankrupt. Seeking a cost-effective method for treating millions of gallons of acid rock drainage (ARD), CDM partnered with Green World Science, Inc. (GWS) of Boise, Idaho, for the development of an in situ bioremediation process that can be used to remove metals from pit lake water. Recent testing revealed that the in situ bioremediation method can successfully remove metals from highly acidic water without the need to construct costly water treatment facilities.
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Fisher, T. S. R., & Lawrence, G. A. (2006). Treatment of acid rock drainage in a meromictic mine pit lake. Journal of environmental engineering, 132(4), 515–526.
Abstract: The Island Copper Mine pit near Port Hardy, Vancouver Island, B.C., Canada, was flooded in 1996 with seawater and capped with fresh water to form a meromictic (permanently stratified) pit lake of maximum depth 350 m and surface area 1.72 km2. The pit lake is being developed as a treatment system for acid rock drainage. The physical structure and water quality has developed into three distinct layers: a brackish and well-mixed upper layer; a plume stirred intermediate layer; and a thermally convecting lower layer. Concentrations of dissolved metals have been maintained well below permit limits by fertilization of the surface waters. The initial mine closure plan proposed removal of heavy metals by metal-sulfide precipitation via anaerobic sulfate-reducing bacteria, once anoxic conditions were established in the intermediate and lower layers. Anoxia has been achieved in the lower layer, but oxygen consumption rates have been less than initially predicted, and anoxia has yet to be achieved in the intermediate layer. If anoxia can be permanently established in the intermediate layer then biogeochemical removal rates may be high enough that fertilization may no longer be necessary. < copyright > 2006 ASCE.
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(2006). World first: Full-scale BioSure plant commissioned. Water Wheel, 5(3), 19–21.
Abstract: ERWAT's Ancor Wastewater Treatment Works on the Far East Rand commissioned a 10 Ml/day full-scale plant to treat toxic mine-water from the Grootvlei gold mine using primary sewage sludge. The R15-million plant is treating sulphate rich acid mine drainage using the Rhodes BioSURE Process. First, the pumped mine-water is treated at a high-density separation (HDS) plant to remove iron and condition pH levels. Then it is pumped two km via a newly-constructed 10 Ml capacity pipeline to the Ancor works. This mine-water is then mixed together with primary sewage sludge in a mixing tank from where a splitter box directs the material to eight biological sulphate reducing reactors or bioreactors. The overflow water which is rich in sulphide is pumped through the main pump station to another mixing box. Here, iron slurry is mixed with the material before it is again divided between four reactor clarifiers for sulphide removal. The overflow water, now containing reduced sulphate levels and virtually no sulphide is pumped to Ancor's biofilters for removal of remaining Chemical Oxygen Demand (COD) and ammonia following the conventional sewage treatment process for eventual release into the Blesbokspruit.
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