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Masarczyk, J., Hansson, C. H., Solomon, R. L., & Hallmans, B. (1989). Desalination Plant at Kwk-debiensko, Poland – Advanced Mine Drainage Water-treatment Engineering for Zero Discharge. Desalination, 75(1-3), 259–287.
Abstract: The river water in Poland has, to a great extent, such a high salinity that it cannot be used as drinking water, agricultural or industrial water. A large environmental project is now under progress in Katowice, Poland, in order to eliminate the wastewater discharge from two coal mines — Debiensko and Budryk. The highly brackish water will be desalinated in a reverse osmosis plant, followed by vapor compression distillation with seed crystals (RCC), crystallization and sodium chloride drying. This zero discharge process will produce about 8,000 m3/d drinking water an 370 tonnes/d NaCl. The paper describes the design of the plant. Trial operation of pre-treatment and reverse osmosis in a pilot plant for design of the full-scale plant at Debiensko is described in a separate paper.
Keywords: mine water treatment
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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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Wolkersdorfer, C. (2005). Mine water tracer tests as a basis for remediation strategies. Chemie der Erde, 65(Suppl. 1), 65–74.
Abstract: Mining usually causes severe anthropogenic changes by which the ground- or surface water might be significantly polluted. One of the main problems in the mining industry are acid mine drainage, the drainage of heavy metals, and the prediction of mine water rebound after mine closure. Therefore, the knowledge about the hydraulic behaviour of the mine water within the flooded mine might significantly reduce the costs of mine closure and remediation. In the literature, the difficulties in evaluating the hydrodynamics of flooded mines are well described, but only few tracer tests in flooded mines have been published so far. Most tracer tests linked to mine water problems were related to either pollution of the aquifer or radioactive waste disposal and not the mine water itself. Applying the results of the test provides possibilities f or optimizing the outcome of the source-path-target methodology and therefore diminishes the costs of remediation strategies. Consequently, prior to planning of remediation strategies or numerical simulations, relatively cheap and reliable results for decision making can be obtained via a well conducted tracer test. < copyright > 2005 Elsevier GmbH. All rights reserved.
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Akcil, A., & Koldas, S. (2006). Acid Mine Drainage (AMD): causes, treatment and case studies. J. Cleaner Prod., 14(12-13), 1139–1145.
Abstract: This paper describes Acid Mine Drainage (AMD) generation and its associated technical issues. As AMD is recognized as one of the more serious environmental problems in the mining industry, its causes, prediction and treatment have become the focus of a number of research initiatives commissioned by governments, the mining industry, universities and research establishments, with additional inputs from the general public and environmental groups. In industry, contamination from AMD is associated with construction, civil engineering mining and quarrying activities. Its environmental impact, however, can be minimized at three basic levels: through primary prevention of the acid-generating process; secondary control, which involves deployment of acid drainage migration prevention measures; and tertiary control, or the collection and treatment of effluent.
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Evangelou, V. P. (2001). Pyrite microencapsulation technologies: Principles and potential field application. Ecological Engineering, 17(2-3), 165–178.
Abstract: In nature, pyrite is initially oxidized by atmospheric O2, releasing acidity and Fe2+. At pH below 3.5, Fe2+ is rapidly oxidized by T. ferrooxidans to Fe3+, which oxidizes pyrite at a much faster rate than O2. Commonly, limestone is used to prevent pyrite oxidation. This approach, however, has a short span of effectiveness because after treatment the surfaces of pyrite particles remain exposed to atmospheric O2 and oxidation continuous abiotically. Currently, a proposed mechanism for explaining non-microbial pyrite oxidation in high pH environments is the involvement of OH- in an inner-sphere electron-OH exchange between pyrite/surface-exposed disulfide and pyrite/surface-Fe(III)(OH)n3-n complex and/or formation of a weak electrostatic pyrite/surface-CO3 complex which enhances the chemical oxidation of Fe2+. The above infer that limestone application to pyritic geologic material treats only the symptoms of pyrite oxidation through acid mine drainage neutralization but accelerates non-microbial pyrite oxidation. Therefore, only a pyrite/surface coating capable of inhibiting O2 diffusion is expected to control long-term oxidation and acid drainage production. The objective of this study was to examine the feasibility in controlling pyrite oxidation by creating, on pyrite surfaces, an impermeable phosphate or silica coating that would prevent either O2 or Fe3+ from further oxidizing pyrite. The mechanism underlying this coating approach involves leaching mine waste with a coating solution composed of H2O2 or hypochlorite, KH2PO4 or H4SiO4, and sodium acetate (NaAC) or limestone. During the leaching process, H2O2 or hypochlorite oxidizes pyrite and produces Fe3+ so that iron phosphate or iron silicate precipitates as a coating on pyrite surfaces. The purpose of NaAC or limestone is to eliminate the inhibitory effect of the protons (produced during pyrite oxidation) on the precipitation of iron phosphate or silicate and to generate iron-oxide pyrite coating, which is also expected to inhibit pyrite oxidation. The results showed that iron phosphate or silicate coating could be established on pyrite by leaching it with a solution composed of: (1) H2O2 0.018-0.16 M; (2) phosphate or silicate 10-3 to 10-2 M; (3) coating-solution pH [approximate]5-6; and (4) NaAC as low as 0.01 M. Leachates from column experiments also showed that silicate coatings produced the least amount of sulfate relative to the control, limestone and phosphate treatments. On the other hand, limestone maintained the leachate near neutral pH but produced more sulfate than the control.
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