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Jarvis, A. P., & Younger, P. L. (2001). Passive treatment of ferruginous mine waters using high surface area media. Water Res., 35(15), 3643–3648.
Abstract: Rapid oxidation and accretion of iron onto high surface area media has been investigated as a potential passive treatment option for ferruginous, net-alkaline minewaters. Two pilot-scale reactors were installed at a site in County Durham, UK. Each 2.0m high cylinder contained different high surface area plastic trickling filter media. Ferruginous minewater was fed downwards over the media at various flow-rates with the objective of establishing the efficiency of iron removal at different loading rates. Residence time of water within the reactors was between 70 and 360s depending on the flow-rate (1 and 12l/min, respectively). Average influent total iron concentration for the duration of these experiments was 1.43mg/l (range 1.08-1.84mg/l; n=16), whilst effluent iron concentrations averaged 0.41mg/l (range 0.20-1.04mg/l; n=15) for Reactor A and 0.38mg/l (range 0.11-0.93mg/l; n=16) for Reactor B. There is a strong correlation between influent iron load and iron removal rate. Even at the highest loading rates (approximately 31.6g/day) 43% and 49% of the total iron load was removed in Reactors A and B, respectively. At low manganese loading rates (approximately 0.50-0.90g/day) over 50% of the manganese was removed in Reactor B. Iron removal rate (g/m3/d) increases linearly with loading rate (g/day) up to 14g/d and the slope of the line indicates that a mean of 85% of the iron is removed. In conclusion, it appears that the oxidation and accretion of ochre on high surface area media may be a promising alternative passive technology to constructed wetlands at certain sites.
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Robbins, E. I., Cravotta, C. A., Savela, C. E., & Nord, G. L. (1999). Hydrobiogeochemical Interactions in 'anoxic' Limestone Drains for Neutralization of Acidic Mine Drainage. Fuel, 78(2), 259–270.
Abstract: Processes affecting neutralization of acidic coal mine drainage were evaluated within 'anoxic' limestone drains (ALDs). Influents had pH less than or equal to 3.5 and dissolved oxygen < 2 mg/l. Even though effluents were near neutral (pH > 6 and alkalinity > acidity), two of the four ALDs were failing due to clogging. Mineral-saturation indices indicated the potential for dissolution of calcite and gypsum, and precipitation of Al3+ and Fe3+ compounds. Cleavage mounts of calcite and gypsum that were suspended within the ALDs and later examined microscopically showed dissolution features despite coatings by numerous bacteria, biofilms, and Fe-Al-Si precipitates. In the drain exhibiting the greatest flow reduction, Al-hydroxysulfates had accumulated onlimestone surfaces and calcite etch points, thus causing the decline in transmissivity and dissolution. Therefore, where Al loadings are high and flow rates are low, a pre-treatment step is indicated to promote Al removal before diverting acidic mine water into alkalinity-producing materials. Published by Elsevier Science Ltd.
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Ettner, D. C. (2007). (R. Cidu, & F. Frau, Eds.). Water in Mining Environments. Cagliari: Mako Edizioni.
Abstract: Previous mining history in Norway has resulted in ongoing release of acid mine drainage. Preservation of the historical sites in mining areas does not allow for remediation technologies that result in significant alteration of the historical landscape. Therefore, alternative remediation techniques such as passive mine water treatment have been tested. The climate in Norway varies from mild coastal climates to artic climates, and one of the challenges with passive treatment systems is the cold winter conditions. Anaerobic treatment systems have been built at Kongens Mine near Røros, at Folldal mines, and at Titania's tailings impoundment near Storgangen Mine. These systems utilize sulfate-reducing bacteria that result in the precipitation of metal sulfides. A full- and pilot-scale system at Kongens Mine and Folldal were built in 2006 to remove copper and zinc from typical ARD in an alpine climate. Previous testing with pilot scale systems at Kongens Mine showed that up to 85% copper and 48% zinc could be removed. At Titania A/S the anaerobic system is designed to remove nickel from neutral waters. At this system over 90% nickel is removed when water flow is regulated at a constant flow. Testing shows that the system can function in cold winter conditions, however, optimal metal removal is achieved under warmer temperatures. Temperatures changes by global climatic warming will not adversely affect these anaerobic systems. However, extreme precipitation events and the resulting rapid fluctuations of ARD runoff will provide a challenge for the effectiveness of these systems.
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Younger, P. L., & Cornford, C. (2002). Mine water pollution from Kernow to Kwazulu-Natal; geochemical remedial options and their selection in practice.
Abstract: Pollution by mine drainage is a major problem in many parts of the world. The most frequent contaminants are Fe, Mn, Al and SO (sub 4) with locally important contributions by other metals/metalloids including (in order of decreasing frequency) Zn, Cu, As, Ni, Cd and Pb. Remedial options for such polluted drainage include monitored natural attenuation, physical intervention to minimise pollutant release, and active and passive water treatment technologies. Based on the assessment of the key hydrological and geochemical attributes of mine water discharges, a rational decision-making framework has now been developed for deciding which (or which combinations) of these options to implement in a specific case. Five case studies illustrate the application of this decision-making process in practice: Wheal Jane and South Crofty (Cornwall), Quaking Houses (Co Durham), Hlobane Colliery (South Africa) and Milluni Tin Mine (Bolivia). In many cases, particularly where the socio-environmental stakes are particularly high, the economic, political and ecological issues will prove even more challenging than the technical difficulties involved in implementing remedial interventions which will be robust in the long term. Hence truly “holistic” mine water remediation is a multi-dimensional business, involving teamwork by a range of geoscientific, hydroecological and socio-economic specialists.
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Konieczny, K. (2003). Mining waters treatment for drinking and economic aims. VI National Polish Scientific Conference on Complex and Detailed Problems of Environmental Engineering, 21, 333–348.
Abstract: Poland is comparatively a poor country in relation to resources of drinking water. In count per capita it is oil one of the last places in Europe. Such state forces to save resources for example by closing water circulations and also desalination of mining waters.
Keywords: mine water treatment
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