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Banks, D., Younger, P. L., Arnesen, R. - T., Iversen, E. R., & Banks, S. B. (1997). Mine-water chemistry: The good, the bad and the ugly. Environ. Geol., 32(3), 157–174.
Abstract: Contaminative mine drainage waters have become one of the major hydrogeological and geochemical problems arising from mankind's intrusion into the geosphere. Mine drainage waters in Scandinavia and the United Kingdom are of three main types: (1) saline formation waters; (2) acidic, heavy-metal-containing, sulphate waters derived from pyrite oxidation, and (3) alkaline, hydrogen-sulphide-containing, heavy-metal-poor waters resulting from buffering reactions and/or sulphate reduction. Mine waters are not merely to be perceived as problems, they can be regarded as industrial or drinking water sources and have been used for sewage treatment, tanning and industrial metals extraction. Mine-water problems may be addressed by isolating the contaminant source, by suppressing the reactions releasing contaminants, or by active or passive water treatment. Innovative treatment techniques such as galvanic suppression, application of bactericides, neutralising or reducing agents (pulverised fly ash-based grouts, cattle manure, whey, brewers' yeast) require further research.
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Ntengwe, F. W. (2005). An overview of industrial wastewater treatment and analysis as means of preventing pollution of surface and underground water bodies – The case of Nkana Mine in Zambia. Phys. Chem. Earth, 30(11-16 Spec. Iss.), 726–734.
Abstract: The wastewaters coming from mining operations usually have low pH (acidic) values and high levels of metal pollutants depending on the type of metals being extracted. If unchecked, the acidity and metals will have an impact on the surface water. The organisms and plants can adversely be affected and this renders both surface and underground water unsuitable for use by the communities. The installation of a treatment plant that can handle the wastewaters so that pH and levels of pollutants are reduced to acceptable levels provides a solution to the prevention of polluting surface and underground waters and damage to ecosystems both in water and surrounding soils. The samples were collected at five points and analyzed for acidity, total suspended solids, and metals. It was found that the pH fluctuated between pH 2 when neutralization was forgotten and pH 11 when neutralization took place. The levels of metals that could cause impacts to the water ecosystem were found to be high when the pH was low. High levels of metals interfere with multiplication of microorganisms, which help in the natural purification of water in stream and river bodies. The fish and hyacinth placed in water at the two extremes of pH 2 and pH 11 could not survive indicating that wastewaters from mining areas should be adequately treated and neutralized to pH range 6-9 if life in natural waters is to be sustained. < copyright > 2005 Elsevier Ltd. All rights reserved.
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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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Tarutis Jr, W. J., Stark, L. R., & Williams, F. M. (1999). Sizing and performance estimation of coal mine drainage wetlands. Ecological Engineering, 12(3-4), 353–372.
Abstract: The effectiveness of wetland treatment of acid mine drainage (AMD) was assessed using three measures of performance: treatment efficiency, area-adjusted removal, and first-order removal. Mathematical relationships between these measures were derived from simple kinetic equations. Area-adjusted removal is independent of pollutant concentration (zero-order reaction kinetics), while first-order removal is dependent on concentration. Treatment efficiency is linearly related to area-adjusted removal and exponentially related to first-order removal at constant hydraulic loading rates (flow/area). Examination of previously published data from 35 natural AMD wetlands revealed that statistically significant correlations exist between several of the performance measures for both iron and manganese removal, but these correlations are potentially spurious because these measures are derived from, and are mathematical rearrangements of, the same operating data. The use of treatment efficiency as a measure of performance between wetlands is not recommended because it is a relative measure that does not account for influent concentration differences. Area-adjusted removal accounts for mass loading effects, but it fails to separate the flow and concentration components, which is necessary if removal is first-order. Available empirical evidence suggests that AMD pollutant removal is better described by first-order kinetics. If removal is first-order, the use of area-adjusted rates for determining the wetland area required for treating relatively low pollutant concentrations will result in undersized wetlands. The effects of concentration and flow rate on wetland area predictions for constant influent loading rates also depend on the kinetics of pollutant removal. If removal is zero-order, the wetland area required to treat a discharge to meet some target effluent concentration is a decreasing linear function of influent concentration (and an inverse function of flow rate). However, if removal is first-order, the required wetland area is a non-linear function of the relative influent concentration. Further research is needed for developing accurate first-order rate constants as a function of influent water chemistry and ecosystem characteristics in order to successfully apply the first-order removal model to the design of more effective AMD wetland treatment systems.
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