Driussi, C. (2006). Technological options for waste minimisation in the mining industry. J. Cleaner Prod., 14(8), 682–688.
Abstract: Just as the application of technology in mining processes can cause pollution, it can also be harnessed to minimise, and sometimes eliminate, mine-related contaminants. Waste minimisation can be achieved through decreased waste production, waste collection, waste recycling, and the neutralisation of pollutants into detoxified forms. This article reviews examples of how technology can be used to minimise air, water, land and noise pollution in the mining industry. (c) 2005 Elsevier Ltd. All rights reserved.
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Lawrence, R. (2002). Technology reduces sulphur compounds – A new way of treating acid mine drainage. Canadian Mining Journal, 123(7), 27.
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Coulton, R., Bullen, C., & Hallett, C. (2003). The design and optimisation of active mine water treatment plants. Land Contam. Reclam., 11(2), 273–280.
Abstract: This paper provides a 'state of the art' overview of active mine water treatment. The paper discusses the process and reagent selection options commonly available to the designer of an active mine water treatment plant. Comparisons are made between each of these options, based on technical and financial criteria. The various different treatment technologies available are reviewed and comparisons made between conventional precipitation (using hydroxides, sulphides and carbonates), high density sludge processes and super-saturation precipitation. The selection of reagents (quick lime, slaked lime, sodium hydroxide, sodium carbonate, magnesium hydroxide, and proprietary chemicals) is considered and a comparison made on the basis of reagent cost, ease of use, final effluent quality and sludge settling criteria. The choice of oxidising agent (air, pure oxygen, peroxide, etc.) for conversion of ferrous to ferric iron is also considered. Whole life costs comparisons (capital, operational and decommissioning) are made between conventional hydroxide precipitation and the high density sludge process, based on the actual treatment requirements for four different mine waters.
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Burt, R. A., & Caruccio, F. T. (1986). The effect of limestone treatments on the rate of acid generation from pyritic mine gangue. Environmental geochemistry and health, 8, 8.
Abstract: Surface water enters the Haile Gold Mine, Lancaster County, South Carolina by means of a small stream and is ponded behind a dam and in an abandoned pit. This water is affected by acidic drainage. In spite of the large exposures of potentially acid producing pyritic rock, the flux of acid to the water is relatively low. Nevertheless, the resulting pH values of the mine water are low (around 3.5) due to negligible buffering capacity. In view of the observed low release of acidity, the potential for acid drainage abatement by limestone ameliorants appears feasible. This study investigated the effects of limestone treatment on acid generation rates of the Haile mine pyritic rocks through a series of leaching experiments. Below a critical alkalinity threshold value, solutions of dissolved limestone were found consistently to accelerate the rate of pyrite oxidation by varying degrees. The oxidation rates were further accelerated by admixing solid limestone with the pyritic rock. However, after a period of about a month, the pyrite oxidation rate of the admixed samples declined to a level lower than that of untreated pyrite. Leachates produced by the pyrite and limestone mixtures contained little if any iron. Further, in the mixtures, an alteration of the pyrite surface was apparent. The observed behaviour of the treated pyrite appears to be related to the immersion of the pyrite grains within a high alkalinity/high pH environment. The high pH increases the rate of oxidation of ferrous iron which results in a higher concentration of ferric iron at the pyrite surface. This, in turn, increases the rate of pyrite oxidation. Above a threshold alkalinity value, the precipitation of hydrous iron oxides at the pyrite surface eventually outpaces acid generation and coats the pyrite surface, retarding the rate of pyrite oxidation.
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Goulet, R. R. (2001). The evaluation of metal retention by a constructed wetland using the pulmonate gastropod Helisoma trivolvis (Say). Archives of Environmental Contamination and Toxicology, 40(3), 303–310.
Abstract: Constructed wetlands are built because they can act as sinks fur many pollutants, thereby protecting the water quality of downstream ecosystems. The treatment performance is generally assessed using mass balance calculations. Along with the mass balance approach, we compared the metal content of populations of a common pond snail (Helisoma trivolvis Say) collected upstream and downstream of a 3-year-old constructed wetland. Snails were collected in early May, June, and August 1998. At the same time, water samples for particulate and dissolved metals were taken every 3 days for the duration of the experiment. Overall, the wetland retained most dissolved metals, including Fe, Mn, Cu, Zn, Ni, and Pb, but released dissolved As. However, the wetland released particulate Fe and Mn. With the exception of Zn, the metal concentrations of the downstream snails were on average higher than those measured in the upstream population. The higher metal content of downstream snails was likely related to the significant export of particulate metals by the wetland, despite the overall retention of dissolved metals. This study points to the need for biological as well as chemical monitoring to determine the treatment efficiency and toxicological risk associated with constructed wetlands.
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