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Walitt, A., Jasinski, R., & Keilin, B. (1970). Silicate treatment of coal mine refuse piles.
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Vegt, A. L. de, Bayer, H. G., & Buisman, C. J. (1998). Biological sulfate removal and metal recovery from mine waters. Min. Eng., 50(11), 67–70.
Abstract: Metalle und Sulfat können aus Grubenwässern in einem zweistufigen biologischen Prozeß entfernt werden. In der ersten Stufe wird das Sulfat durch Bakterien zu Schwefelwasserstoff reduziert. Dieser reagiert mit den gelösten Metallen zu unlöslichem Metallsulfid. Im zweiten Schritt wird überschüssiger Schwefelwasserstoff durch Bakterien zu elementarem Schwefel oxidiert. Eine nach diesem Verfahren arbeitende Anlage wurde 1992 durch die Budelco Zinc Refinery in den Niederlanden installiert. Diese verarbeitet täglich 5000 m(exp 3) Gundwasser. Zur Weiterentwicklung des Verfahrens für die Entfernung von Metallen und Sulfat aus Grundwasser und zur gezielten Kupfergewinnung aus Laugungswässern wurde 1995 in der Kupfergrube Bingham Canyon Utah, USA eine entsprechende Pilotanlage in Betrieb genommen. Anhand dieser Pilotanlage werden der Verfahrensablauf und erste Erfahrungen dargestellt sowie ein Überblick über das Untersuchungsprogramm gegeben.
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Van Hille, R. P., Boshoff, G. A., Rose, P. D., & Duncan, J. R. (1999). A continuous process for the biological treatment of heavy metal contaminated acid mine water. Resour. Conserv. Recycl., 27(1-2), 157–167.
Abstract: Alkaline precipitation of heavy metals from acidic water streams is a popular and long standing treatment process. While this process is efficient it requires the continuous addition of an alkaline material, such as lime. In the long term or when treating large volumes of effluent this process becomes expensive, with costs in the mining sector routinely exceeding millions of rands annually. The process described below utilises alkalinity generated by the alga Spirulina sp., in a continuous system to precipitate heavy metals. The design of the system separates the algal component from the metal containing stream to overcome metal toxicity. The primary treatment process consistently removed over 99% of the iron (98.9 mg/l) and between 80 and 95% of the zinc (7.16 mg/l) and lead (2.35 mg/l) over a 14-day period (20 l effluent treated). In addition the pH of the raw effluent was increased from 1.8 to over 7 in the post-treatment stream. Secondary treatment and polishing steps depend on the nature of the effluent treated. In the case of the high sulphate effluent the treated stream was passed into an anaerobic digester at a rate of 4 l/day. The combination of the primary and secondary treatments effected a removal of over 95% of all metals tested for as well as a 90% reduction in the sulphate load. The running cost of such a process would be low as the salinity and nutrient requirements for the algal culture could be provided by using tannery effluent or a combination of saline water and sewage. This would have the additional benefit of treating either a tannery or sewage effluent as part of an integrated process.
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Ueki, K., Kotaka, K., Itoh, K., & Ueki, A. (1988). Potential availability of anaerobic treatment with digester slurry of animal waste for the reclamation of acid mine water containing sulfate and heavy metals. Journal of Fermentation Technology, 66(1).
Abstract: The use of an anaerobic digester slurry of cattle waste for the reclamation of acid mine water was examined. When the digester slurry was mixed with acid mine water, anaerobic digestion, including sulfate reduction and methanogenesis, was enhanced. In the mixture of acid mine water and the digester slurry, sulfate reduction proceeded without diminishing methanogenesis. The digester slurry and its supernatant (SDF-sup) showed a significant capacity to act as a strong alkaline reagent, and the pH of the acid mine water was markedly elevated by the addition of the digester slurry of SDF-sup even at the low ratio of 1% (v/v). Precipitation of heavy metals in the acid mine water occurred as the pH was elevated by the addition of SDF-sup. When the digester slurry was added at the ratio of 5% (v/v) to acid mine water which had been pretreated with SDF-sup, the rate of sulfate reduction increased with increasing the concentration of sulfate in the mixture up to about 1,400 mg·l-1. In acid mine water pretreated with SDF-sup and supplemented with the digester slurry at the ratio of 5% (v/v), the maximum amount of sulfate reduced within 20 d of incubation was about 1,000 mg·l-1, and the maximum rate of sulfate reduction was about 120 mg SO42-·l-1·d-1.
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Turek, M., & Gonet, M. (1997). Nanofiltration in the utilization of coal-mine brines. Desalination, 108(1-3), 171–177.
Abstract: The utilization of saline coal mine waters is considered to be the most adequate method of solving ecological problems caused by this kind of water in Poland. In the case of most concentrated waters, the so-called coalmine brines, the method of concentrating by evaporation in a twelve-stage expansion installation or vapour compression is applied, after which sodium chloride is manufactured. A considerable restriction in the utilization of coal mine brines is the high energy consumption in these methods of evaporation. An obstacle in the application of low energy evaporation processes, e.g. multi-stage flash, is the high concentration of calcium and sulfate ions in the coal mine brines. The present paper deals with the application of nanofiltration in the pretreatment of the brine. The application of nanofiltration membranes with an adequate pore size, including charged membranes, makes it possible to decrease the concentration of divalent ions in the permeate practically without any changes in the concentration of sodium chloride. Then the permeate may be concentrated in a multi-stage evaporation process, e.g. MSF, without any risk of the crystallization of gypsum. A combination of NF and MSF ought to set down the unit costs of the concentration of coal mine brines below those of mere evaporation.
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