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Hayward, D., & Barnard, R. (1993). Treatment of acid mine wastewaters. Behandlung saurer Grubenwässer. World Mining Equipment, 17(6), 36–37.
Abstract: Überblick über einschlägige Verfahren zum Ausfällen der sauren Betandteile, Entfernen der Schwermetalle, und Einstellen des pH-Wertes auf einen Wert von 6 bis 9. Hauptsächliche Verfahren zum Ausfällen sind: Ausfällen mit Kalkhydrat (Ca(OH)2), mit Kalkstein, Calcium- oder Natriumsulfid. Durch Abtrennen des Niederschlages in einem Kläreindicker und zusätzliche Reinigung durch Filtrieren kann ein Anteil von 90% der unlöslichen Schwermetallverbindungen entfernt werden. Allgemein wird mit diesem Verfahren ein Standardgehalt von 5 mg/l erreicht. Durch zusätzliche Anwendung physikochemischer Verfahren kann der Schwermetallgehalt weiter gesenkt werden: Mikrofiltration, Umkehrosmose, Elektrodialyse, Ionenaustausch, biochemische und spezielle chemische Verfahren können je nach Eigenart der Grubenwässer verwendet werden.
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Perry, A., & Kleinmann, R. L. P. (1991). The use of constructed wetlands in the treatment of acid mine drainage. Natural Resources Forum, 15(3), 178–184.
Abstract: US government regulations require that all effluents from industrial operations, including mining, meet certain water quality standards. Constructed wetlands have proven to be useful in helping to attain those standards. Application of this biotechnology to mine water drainage can reduce water treatment costs and improve water quality in streams and rivers adversely affected by acidic mine water drainage from abandoned mines. Over 400 constructed wetland water treatment systems have been built on mined lands largely as a result of research by the US Bureau of Mines. Wetlands are passive biological treatment systems that are relatively inexpensive to construct and require minimal maintenance. Chemical treatment costs are reduced sufficiently to repay the cost of construction in less than a year. The mine waste water is typically treated in a series of excavated ponds that resemble small marsh areas. The ponds are engineered to facilitate bacterial oxidation of iron. Ideally, the water then flows through a composted organic substrate supporting a population of sulphate-reducing bacteria which raises the pH. Constructed wetlands in the US are described – their history, functions, construction methodologies, applicabilities, limitations and costs. -Authors
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Jarvis, A. P., & Younger, P. L. (1999). Design, construction and performance of a full-scare compost wetland for mine-spoil drainage treatment at quaking houses. Jciwem, 13(5), 313–318.
Abstract: Acidic spoil-heap drainage, containing elevated concentrations of iron, aluminium and manganese, has been polluting the Stanley Burn in County Durham for nearly two decades. Following the success of a pilot-scale wetland (the first application of its kind in Europe), a full-scale wetland was installed. Waste manures and composts have been used as the main substrate which is contained within embankments constructed from compacted pulverized fuel ash. The constructed wetland, which cost less than £20,000 to build, has consistently reduced iron and aluminium concentrations and has markedly lowered the acidity of the drainage. A third phase of activities at the site aims to identify and eliminate pollutant-release 'hot spots' within the spoil.
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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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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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