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Fisher, T. S. R., & Lawrence, G. A. (2006). Treatment of acid rock drainage in a meromictic mine pit lake. Journal of environmental engineering, 132(4), 515–526.
Abstract: The Island Copper Mine pit near Port Hardy, Vancouver Island, B.C., Canada, was flooded in 1996 with seawater and capped with fresh water to form a meromictic (permanently stratified) pit lake of maximum depth 350 m and surface area 1.72 km2. The pit lake is being developed as a treatment system for acid rock drainage. The physical structure and water quality has developed into three distinct layers: a brackish and well-mixed upper layer; a plume stirred intermediate layer; and a thermally convecting lower layer. Concentrations of dissolved metals have been maintained well below permit limits by fertilization of the surface waters. The initial mine closure plan proposed removal of heavy metals by metal-sulfide precipitation via anaerobic sulfate-reducing bacteria, once anoxic conditions were established in the intermediate and lower layers. Anoxia has been achieved in the lower layer, but oxygen consumption rates have been less than initially predicted, and anoxia has yet to be achieved in the intermediate layer. If anoxia can be permanently established in the intermediate layer then biogeochemical removal rates may be high enough that fertilization may no longer be necessary. < copyright > 2006 ASCE.
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Foucher, S., Battaglia-Brunet, F., Ignatiadis, I., & Morin, D. (2001). Treatment by sulfate-reducing bacteria of Chessy acid-mine drainage and metals recovery. Chemical Engineering Science, 56(4), 1639–1645.
Abstract: Acid-mine drainage can contain high concentrations of heavy metals and release of these contaminants into the environment is generally avoided by lime neutralization. However, this classical treatment is expensive and generates large amounts of residual sludge. The selective precipitation of metals using H2S produced biologically by sulfate-reducing bacteria has been proposed as an alternative process. Here, we report on experiments using real effluent from the disused Chessy-les-Mines mine-site at the laboratory pilot scale. A fixed-bed bioreactor, fed with an H2/CO2 mixture, was used in conjunction with a gas stripping column. The maximum rate of hydrogen transfer in the bioreactor was determined before inoculation. kLa was deduced from measurements of O2 using Higbie and Danckwert's models which predict a dependence on diffusivity. The dynamic method of physical absorption and desorption was used. The maximum rate of H2 transfer suggests that this step should not be a limiting factor. However, an increase in H2 flow rate was observed to induce an increase in sulfate reduction rate. For the precipitation step, the gas mixture from the bioreactor was bubbled into a stirred reactor fed with the real effluent. Cu and Zn could be selectively recovered at pH=2.8 and pH=3.5, respectively. Other impurities such as Ni and Fe could also be removed at pH=6 by sulfide precipitation. Part of the outlet stream from the bioreactor was used to regulate and maintain the pH during sulfide precipitation by feeding the outlet stream back into the bioreactor. The replacement of synthetic medium with real effluent had a positive effect on sulfate reduction rate which increased by 30-40%. This improvement in bacterial efficiency may be related to the large range of oligo-elements provided by the mine-water. The maximum sulfate reduction rate observed with the real effluent was 200 mgl-1 h-1, corresponding to a residence time of 0.9 day. A preliminary cost estimation based on a treatment rate of 5 m3 h-1 of a mine effluent containing 5 gl-1 SO42- is presented.
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Fricke, J., Blickwedel, R., & Hagerty, P. (1997). Biotreatment of metal mine waste waters; case histories. Open-File Report – US Geological Survey, Of 97-0496, 25.
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Gazea, B., Adam, K., & Kontopoulos, A. (1996). A review of passive systems for the treatment of acid mine drainage. Minerals Engineering, 9(1), 23–42.
Abstract: This review presents the current state of development of the passive mine water treatment technologies. The background of passive treatment is reviewed and the chemical and biological processes involved in metals removal and acidity neutralisation are detailed. The types of currently existing passive treatment technologies and their applicability range as defined by the mine water chemistry are presented. Finally, the performance of passive systems constructed for the treatment of acid mine drainage from both coal and sulphide metal mines is summarised.
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Guo, F., & Yu, H. (1993). Hydrogeochemistry and treatment of acid mine drainage in southern China. In B. A. Zamora, & R. E. Connolly (Eds.), Proceedings of the Annual National Meeting – American Society for Surface Mining and Reclamation, vol.10 (pp. 277–283). The challenge of integrating diverse perspectives in reclamation.
Abstract: Coal mines and various sulfide ore deposits are widely distributed in Southern China. Acid mine drainage associated with coal and metal sulfide deposits affects water quality in some mined areas of Southern China. Mining operations accelerate this natural deterioration of water quality by exposing greater surface areas of reactive minerals to the weathering effects of the atmosphere, hydrosphere, and biosphere. Some approaches to reduce the effects of acid mine drainage on water quality are adopted, and they can be divided into two aspects: (a) Man-made control technology based on long-term monitoring of acid mine drainage; and, (b) Neutralization of acidity through the addition of lime. It is important that metals in the waste water are removed in the process of neutralization. A new method for calculating neutralization dosage is applied. It is demonstrated that the calculated value is approximately equal to the actual required value.
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