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Turek, M. (2000). Recovery of NaCl from saline mine water in the ED-MSF system. 8th World Salt Symposium, Vols 1 and 2, , 471–475.
Abstract: A considerable part of water obtained by drainage of Polish coal-mines is saline which creates substantial ecological problems. The load of salt (mainly sodium chloride) amounts to 5 min t/year. Despite the utilisation of saline coalmine waters is considered to be the most adequate method of solving ecological problems caused by this kind of water in Poland there are only two installations utilising coal-mine waters and producing 100,000 t salt per year. In the case of the most concentrated waters, the so-called coal-mine brines, the method of concentrating by evaporation in twelve-stage expansion installation or vapour compression is applied, after which sodium chloride is manufactured. In the case of low salinity waters they are preconcentrated first by RO method. High energy consumption in above-mentioned methods of evaporation is a considerable restriction in the utilisation of coal-mine brines. An obstacle in the application of low energy evaporation processes, e.g. multi-stage flash, is the high concentration of calcium and sulphate ions in the coal-mine waters.
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Tsukamoto, T. K., & Miller, G. C. (1999). Methanol as a Carbon Source for Microbiological Treatment of Acid Mine Drainage. Water Res., 33(6), 1365–1370.
Abstract: Sulfate reducing passive bioreactors are increasingly being used to remove metals and raise the pH of acidic waste streams from abandoned mines. These systems commonly use a variety of organic substrates (i.e. manure, wood chips) for sulfate reduction. The effectiveness of these systems decreases as easily accessible reducing equivalents are consumed in the substrate through microbial activity. Using column studies at room temperature (23-26 degrees C), we investigated the addition of lactate and methanol to a depleted manure substrate as a method to reactivate a bioreactor that had lost >95% of sulfate reduction activity. A preliminary experiment compared sulfate removal in gravity fed, flow through bioreactors in which similar masses of each substrate were added to the influent solution. Addition of 148 mg/l lactate resulted in a 69% reduction in sulfate concentration from 300 to 92 mg/l, while addition of 144 mg/l methanol resulted in an 88% reduction in sulfate concentration from 300 to 36 mg/l. Because methanol was found to be an effective sulfate reducing substrate, it was chosen for further experiments due to its inherent physical properties (cost, low freezing point and low viscosity liquid) that make it a superior substrate for remote, high elevation sites where freezing temperatures would hamper the use of aqueous solutions. In these column studies, water containing sulfate and ferrous iron was gravity-fed through the bioreactor columns, along with predetermined methanol concentrations containing reducing equivalents to remove 54% of the sulfate. Following an acclimation period for the columns, sulfate concentrations were reduced from of 900 mg/l in the influent to 454 mg/l in the effluent, that reflects a 93% efficiency of electrons from the donor to the terminal electron acceptor. Iron concentrations were reduced from 100 to 2 mg/l and the pH increased nearly 2 units. (C) 1999 Elsevier Science Ltd.
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Tredinnick, I. A., & Cornwell, P. J. (1995). A manager's operational perspective of AMD management at the Pajingo Gold Mine. Die Beherrschung des AMD-Problems in der Pajingo Gold Mine aus der Sicht des Managers. In Second Australian Acid Mine Drainage Workshop, Charters Towers, AU, 28 31 March 1995 (pp. 43–51).
Abstract: Nach einer Beschreibung der Bergbauaktivitäen (Tief- und Tagebau) in der australischen Goldlagerstätte Pajingo wird detailliert auf die Bemühungen zur Gewährleistung des Umweltschutzes und vor allem auf die Minimierung der Freisetzung saurer Grubenwässer eingegangen. Die bei der Lösung der Aufgabenstellung zu beachtenden Besonderheiten resultieren aus der kurzen Lebensdauer der Grube, in der die 1987 begonnene Abbautätigkeit bereits im Jahr 1996 wieder beendet wurde. Aus diesem Grund wurden bereits im Planungsstadium und während der Abbautätigkeit vorbeugende Strategien zur Minimierung des AMD-Problems verwirklicht, die ausführlich beschrieben werden. Sulfidische Berge und Aufbereitungsrückstände wurden planmäßig so aufgehaldet oder eingelagert, daß sie stets von einer Schutzschicht aus oxidischem Material umgeben waren. Durch diese Einkapselung reaktionsfähiger sulfidischer Bestandteile sowie die Abdeckung der Tailings des Aufbereitungsprozesses gelang es, die Auswirkungen der Säuregenerierung zu minimieren. Es werden die betrieblichen Erfahrungen, die technologischen Besonderheiten und die Monitoringaktivitäten beschrieben. Es werden auch Angaben zum Kostenaufwand gemacht.
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Totsche, O., Fyson, A., Kalin, M., & Steinberg Christian, E. W. (2006). Titration curves: A useful instrument for assessing the buffer systems of acidic mining waters. ESPR Environmental Science and Pollution Research, 13(4), 215–224.
Abstract: The acidification of mine waters is generally caused by metal sulfide oxidation, related to mining activities. These waters are characterized by low pH and high acidity due to strong buffering systems. The standard acidity parameter, the BNC (Base Neutralization Capacity), is determined by endpoint titration, and reflects a cumulative parameter of both hydrogen ions and all buffering systems, but does not give information on the individual buffer systems. It is demonstrated that a detailed interpretation of titration curves can provide information about the strength of the buffering systems. The buffering systems are of importance for environmental studies and treatment of acidic mining waters. Titrations were carried out by means of an automatic titrator using acidic mining waters from Germany and Canada. The curves were interpreted, compared with each other, to endpoint titration results and to elemental concentrations contained therein. The titration curves were highly reproducible, and contained information about the strength of the buffer systems present. Interpretations are given, and the classification and comparison of acidic mining waters, by the nature and strength of their buffering systems derived from titration curves are discussed. The BNC-values calculated from the curves were more precise than the ones determined by the standard endpoint titration method. Due to the complex buffer mechanisms in acidic mining waters, the calculation of major metal concentrations from the shape of the titration curve resulted in estimates, which should not be confused with precise elemental analysis results. Conclusion. Titration curves provide an inexpensive, valuable and versatile tool, by which to obtain sophisticated information of the acidity in acidic water. The information about the strength of the present buffer systems can help to understand and document the complex nature of acidic mining water buffer systems. Finally, the interpretation of titration curves could help to improve treatment measurements and the ecological understanding of these acidic waters.
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Tempel, R. N. (2000). A quantitative approach to optimize chemical treatment of acid drainage using geochemical reaction path modeling methods: Climax Mine, Colorado. ICARD 2000, Vols I and II, Proceedings, , 1053–1058.
Abstract: The Climax Mine, near Leadville, Colorado treats acid drainage in a lime neutralization chemical treatment system. Chemical treatment has been successful in reducing the concentration of metals to below surface water discharge effluent limits, but lime usage has not been optimized. A geochemical modeling approach has been developed to increase the efficiency of lime neutralization. The modeling approach incorporates two steps: (1)calibration, and (2) calculation of amount of lime needed to increase pH and remove metals. Results of our work quantify the lime treatment process and improve our ability to predict overall water quality.
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