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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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Okuda, T., Ema, S., Ishizaki, C., & Fujimoto, J. (1991). Mine drainage treatment and ferrite sludge application. NEC Technical Journal, 44(5), 4–16.
Abstract: The `ferrite process' is an excellent method for treating waste water containing iron and arsenic, but cannot be directly applied to mine drainage where silicon and aluminum ions are present, because they strongly inhibit ferrite formation. As a result of the development of related technologies such as the elimination of silicon, the concentration of iron, and the oxidation of ferrous ions using iron-oxidation bacteria, a new ferrite formation process has been developed and applied to the mine drainage of the Matsuo Mine. The paper discusses the application of the ferrite sludge to magnetic marking materials, magnetic fluid for metal separation and recovery, and the semiactive magnetic damper is described. The related technologies which will be expected to play an important role in solving the environmental problems are also described. These technologies will change the ferrite sludge to beneficial materials, which can be used for carbon dioxide decomposing catalysts, reuse of dry batteries, fish gathering blocks, and cement tracer for ground improvement
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Bauroth, M., Hähne, R., & Wolf, J. (1991). Erfahrungen bei der Dekontamination saurer Wässer des Uranbergbaus mittels Einbindung in Kraftwerksaschen. Decontamination of acit water from uranium mining by ash filtration method. Neue Bergbautechnik, (12), 420–422.
Abstract: Kontaminierte Grubenwässer des Uranbergbaus in Sachsen und Thüringen weisen eine regional schwankende chemische Zusammensetzung auf (Härte: 50 bis 1500 (Grad) dH, Sulfat: 2 bis 30 g/l, Eisen: 0,5 bis 4 g/l, Uranium: 1 bis 20 mg/l). Eine erfolgreich praktizierte Technologie der Abwasserreinigung ist dessen Verrieselung auf Kraftwerksaschen, die auf dichtem Untergrund bzw. dort, wo eine Grundwasserkontamination auszuschließen ist, aufgehaldet werden. Ziel ist es, den Nutzungsgrad der Asche zur Sicherung des Gewässerschutzes zu erhöhen. Eine geeignete Technologie ist dabei auch die Mischung von Asche und Kalk. Da die berieselte Asche bei der Einwirkung von natürlichen Niederschlägen ihre Kontamination teilweise wieder freisetzt, werden an die Verwahrung sowie Deponiebeschaffenheit von Aschehalden besondere Anforderungen gestellt. So muß beispielsweise die Verdunstung erhöht (Bewuchs, Vegetation) sowie die Dränage der infiltrierte Wässer verzögert werden.
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Kalin, M., Cairns, J., & McCready, R. (1991). Ecological engineering methods for acid mine drainage treatment of coal wastes. Resources, conservation and recycling, 5(2-3), 265–275.
Abstract: The treatment of acid mine drainage (AMD) through the utilization of alkali generating microbes has potential as an alternate approach to conventional lime treatment. Organic matter, a source of fixed carbon for the alkali generating microbial ecosystem, has been tested in 6 different types of AMD. The AMD characteristics range in acidities from 2 mg/l to 900 mg/l (CaCO3 equivalent), while sulphate concentrations range from 75 to 7300 mg/l. Alkali generating populations identified include iron reducers, sulphate reducers and ammonifiers. In coal AMD amended with organic matter, the microbial alkali generation is dominated by ammonifiers. Concentrations of Al, Fe and Zn in the AMD water decreased with concurrent increases in pH (3.2 to 6.5) in localized areas in the test cells.
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Baker, K. A., Fennessy, M. S., & Mitsch, W. J. (1991). Designing wetlands for controlling coal mine drainage: an ecologic- economic modelling approach. Ecological Economics, 3(1), 1–24.
Abstract: A simulation model is developed of the efficiency and economics of an application of ecotechnology – using a created wetland to receive and treat coal mine drainage. The model examines the role of loading rates of iron on treatment efficiencies and the economic costs of wetland versus conventional treatment of mine drainage. It is calibrated with data from an Ohio wetland site and verified from multi-site data from Tennessee and Alabama. The model predicts that iron removal is closely tied to loading rates and that the cost of wetland treatment is less than that of conventional for iron loading rates of approximately 20-25 g Fe m “SUP -2” day “SUP -1” and removal efficiencies less than 85%. A wetland to achieve these conditions would cost approximately US$50 000 per year according to the model. When higher loading rates exist and higher efficiencies are needed, wetland systems are more costly than conventional treatment. -Authors
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