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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.
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Younger, P. L. (2003). Passive in situ remediation of acidic mine waste leachates: progress and prospects. Land Reclamation: Extending the Boundaries, , 253–264.
Abstract: The reclamation of former mining sites is a major challenge in many parts of the world. In relation to the restoration of spoil heaps (mine waste rock piles) and similar bodies of opencast backfill, key challenges include (i) the establishment of stable slopes and minimization of other geotechnical hazards (ii) developing and maintaining a healthy vegetative cover (iii) managing the hydrological behaviour of the restored ground. Significant advances have been made over the past four decades in relation to all four of these objectives. One of the most recalcitrant problems is the ongoing generation and release of acidic leachates, which typically emerge at the toes of (otherwise restored) spoil heaps in the form of springs and seepage areas. Such features are testament to the presence of a “perched” groundwater circulation system within the spoil, and their acidity reflects the continued penetration of oxygen to zones within the heaps which contain reactive pyrite (and other iron sulphide minerals). Two obvious strategies for dealing with this problem are disruption of the perched groundwater system and/or exclusion of oxygen entry. These strategies are now being pursued with considerable success where spoil is being reclaimed for the first time, by the installation of two types of physical barrier (dry covers and water covers). However, where a spoil heap has already been revegetated some decades ago, the destruction of an established sward or woodland in order to retro-fit a dry cover or water cover is rarely an attractive option for dealing with the “secondary dereliction” represented by ongoing toe seepages of acidic leachates. More attractive by far are passive treatment techniques, in which the polluted water is forced to flow through reactive media which serve to neutralize its acidity and remove toxic metals from solution. A brief historical review of the development of such systems reveals a general progression from using limestone as the key neutralizing agent, through a combined use of limestone and compost, to systems in which almost all of the neutralization is achieved by means of bacterial sulphate reduction in the saturated compost media of subsurface-flow bioreactors. In almost all cases, these passive treatment systems include an aerobic, surface flow wetland as the final “polishing” step in the treatment process. Such wetlands combine treatment functions (efficient removal of metals from the now-neutralized waters down to low residual concentrations, and re-oxygenating the water prior to discharge to receiving watercourses) with amenity value (attractive areas for recreational walking, bird-watching etc) and ecological value.
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Norton, P. J. (1992). The Control of Acid Mine Drainage with Wetlands. Mine Water Env., 11(3), 27–34.
Abstract: The recent increases in environmental legislation, especially in the USA'have meant that there is a need on behalf of the mining companies for more judicious operational planning and more thorough restoration techniques in order to reduce costs and prevent violation of the smctly enforced regulations. Water pollution is probably the greatest problem and many less enlightened operators, especially for example, in surface coal milling in Pennsylvania, have been forced into liquidation after having been unable to meet the severe restrictions on Acid Mine Drainage (AMD). The problems of AMD are also inherent in most forms of metalliferous and coal mining and also in some types of aggregate quarrying. As excavations go deeper in search of ever diminishing reserves then they are more likely to encounter groundwater which can become polluted if insufficient care is not taken. It is to be expected that the laws will also become more severe than they are at present in Europe and methods of treatment of AMD will need to be developed that are more efficient than the costly chemical methods currently used. Research by the author and others into the source of AMD pollution and its treatment with engineered wetlands and other operational methods are discussed in the paper. The methods have- the distinct benefit that they are cheap to install, are cost effective over a long period with the minimum of supervision and are environmentally acceptable to the planning and regulatory authorities.
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Zhuang, J. M. (2004). Lignor(TM) process for acidic rock drainage treatment. Environ. Technol., 25(9), 1031–1040.
Abstract: The process using lignosulfonates for acidic rock drainage (ARD) treatment is referred to as the Lignor(TM) process. Lignosulfonates are waste by-products produced in the sulfite pulping process. The present study has shown lignosulfonates are able to protect lime from developing an external surface coating, and hence to favor its dissociation. Further, the addition of lignosulfonates to ARD solutions increased the clotting and settling rate of the formed sludge. The capability of lignosulfonates to form stable metal-lignin complexes makes them very useful in retaining metal ions and thus improving the long-term stability of the sludge against leaching. The Lignor(TM) process involves metal sorption with lignosulfonates, ARD neutralization by lime to about pH 7, pH adjustment with caustic soda to 9.4 – 9.6, air oxidation to lower the pH to a desired level, and addition of a minimum amount of FeCl3 for further removal of dissolved metals. The Lignor(TM) process removes all concerned metals (especially Al and Mn) from the ARD of the Britannia Mine (located at Britannia Beach, British Columbia, Canada) to a level lower than the limits of the B.C. Regulations. Compared with the high-density sludge (HDS) process, the Lignor(TM) process has many advantages, such as considerable savings in lime consumption, greatly reduced sludge volume, and improved sludge stability.
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Potgieter-Vermaak, S. S., Potgieter, J. H., Monama, P., & Van Grieken, R. (2006). Comparison of limestone, dolomite and fly ash as pre-treatment agents for acid mine drainage. Minerals Engineering, 19(5), 454–462.
Abstract: The physical, chemical and biological nature of Vaal Dam water, the main source of water in Gauteng, South Africa, is often affected by underground water pollution (acid mine water) and industrial effluents. The ecological significance and detrimental effects necessitate investigations into treating the water prior to discharge into public streams. Although several acid mine water treatment techniques and methods exist, they all have certain disadvantages. Lime treatment is the most common approach. In this investigation, limestone, dolomite and fly ash were selected as pre-treatment agents based on their low cost. Simulated acid mine water containing these agents was tested using a Jar Test apparatus. Samples were analyzed before and after treatment for pH, ferrous, ferric, calcium, magnesium and sulphate ions. The study demonstrated that the quality of the water improved with an increase in the amount and surface area of the raw material dosed and an increase in contact time. It was also influenced by the chemical composition of the acid mine water and aeration. Chemical cost savings of 38% are achieved when lime is replaced with limestone, and cost savings of 23% and 48% can be accomplished when limestone is substituted with dolomite and fly ash respectively. This could result in significant savings to the gold and coal mining industries, and could lead to a mutual benefit/gain between industrialists/polluters and the public.
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