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Hayward, D., & Barnard, R. (1993). Treatment of acid mine wastewaters. Behandlung saurer Grubenwässer. World Mining Equipment, 17(6), 36–37.
Abstract: Überblick über einschlägige Verfahren zum Ausfällen der sauren Betandteile, Entfernen der Schwermetalle, und Einstellen des pH-Wertes auf einen Wert von 6 bis 9. Hauptsächliche Verfahren zum Ausfällen sind: Ausfällen mit Kalkhydrat (Ca(OH)2), mit Kalkstein, Calcium- oder Natriumsulfid. Durch Abtrennen des Niederschlages in einem Kläreindicker und zusätzliche Reinigung durch Filtrieren kann ein Anteil von 90% der unlöslichen Schwermetallverbindungen entfernt werden. Allgemein wird mit diesem Verfahren ein Standardgehalt von 5 mg/l erreicht. Durch zusätzliche Anwendung physikochemischer Verfahren kann der Schwermetallgehalt weiter gesenkt werden: Mikrofiltration, Umkehrosmose, Elektrodialyse, Ionenaustausch, biochemische und spezielle chemische Verfahren können je nach Eigenart der Grubenwässer verwendet werden.
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Younger, P. L. (2000). Holistic remedial strategies for short- and long-term water pollution from abandoned mines. Transactions of the Institution of Mining and Metallurgy Section a-Mining Technology, 109, A210–A218.
Abstract: Where mining proceeds below the water-table-as it has extensively in Britain and elsewhere-water ingress is not only a hindrance during mineral extraction but also a potential liability after abandonment. This is because the cessation of dewatering that commonly follows mine closure leads to a rise in the water-table and associated, often rapid, changes in the chemical regime of the subsurface. Studies over the past two decades have provided insights into the nature and time-scales of these changes and provide a basis for rational planning of mine-water management during and after mine abandonment. The same insights into mine-water chemistry provide hints for the efficient remediation of pollution (typically due to Fe, Mn and Al and, in some cases, Zn, Cd, Pb and other metals). Intensive treatment (by chemical dosing with enhanced sedimentation or alternative processes, such as sulphidization or reverse osmosis) is often necessary only during the first few years following complete flooding of mine voids. Passive treatment (by the use of gravity-flow geochemical reactors and wetlands) may be both more cost-effective and ecologically more responsible in the long term. By the end of 1999 a total of 28 passive systems had been installed at United Kingdom mine sites, including examples of system types currently unique to the United Kingdom. Early performance data for all the systems are summarized and shown to demonstrate the efficacy of passive treatment when appropriately applied.
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Norris, R. H. (1987). Effectiveness Of Mine Rehabilitation In Relation To Water-Quality. Acta Biologica Hungarica, 38(1), 127–139.
Abstract: When mining is completed the sites may be completely restored to the originalecosystem, rehabilitated for some desirable environmental characteristics, desirable alternative ecosystemscreated or just neglected. The strategy adopted will depend on the intended uses of the parts of theenvironment (including water) affected by the mining. An example of rehabilitation of a metal mine nearthe Australian Federal Capital is used to illustrate the problems that may be encountered. These include:lack of controls while mining is underway; catastrophic events, such as the collapse of a settling dam,lack of site specific understanding of pyrite oxidation processes, particularly those that are biologicallyenhanced; the need for adequate biological information on which to base decisions to meet biologicalinformation on which to base decisions to meet biological objectives. Experience has shown that biologicalcollections such studies should be stored in museums where they will be valuable for comparisons of changesover long periods.
Keywords: mine water treatment
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Eger, P. (1994). Wetland Treatment for Trace-metal Removal from Mine Drainage – the Importance of Aerobic and Anaerobic Processes. Water Sci. Technol., 29(4), 249–256.
Abstract: When designing wetland treatment systems for trace metal removal, both aerobic and anaerobic processes can be incorporated into the final design. Aerobic processes such as adsorption and ion exchange can successfully treat neutral drainage in overlandflow systems. Acid drainage can be treated in anaerobic systems as a result of sulfate reduction processes which neutralize pH and precipitate metals.Test work on both aerobic and anaerobic systems has been conducted in Minnesota. For the past three years, overland flow test systems have successfully removed copper, cobalt, nickel and zinc from neutral mine drainage. Nickel, which is the major contaminant, has been reduced around 90 percent from 2 mg/L to 0.2 mg/L. A sulfate reduction system has successfully treated acid mine drainage for two years, increasing pH from 5 to over 7 and reducing concentrations of all metals by over 90 percent.Important factors to consider when designing wetlands to remove trace metals include not only the type of wetlandrequired but also the size of the system and the residence time needed to achieve the water quality standards.
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Sibrell, P. L. (2000). ARD remediation with limestone in a CO2 pressurized reactor. ICARD 2000, Vols I and II, Proceedings, , 1017–1026.
Abstract: We evaluated a new process for remediation of acid rock drainage (ARD). The process treats ARD with intermittently fluidized beds of granular limestone maintained within a continuous now reactor pressurized with CO2. Tests were performed over a thirty day period at the Toby Creek mine drainage treatment plant, Elk County, Pennsylvania in cooperation with the Pennsylvania Department of Environmental Protection. Equipment performance was established at operating pressures of 0, 34, 82, and 117 kPa using an ARD flow of 227 L/min. The ARD had the following characteristics: pH, 3.1; temperature, 10 OC; dissolved oxygen, 6.4 mg/L; acidity, 260 mg/L; total iron, 21 mg/L; aluminum, 22 mg/L; manganese, 7.5 mg/L; and conductivity, 1400 muS/cm. In all cases tested, processed ARD was net alkaline with mean pH and alkalinities of 6.7 and 59 mg/L at a CO2 pressure of 0 kPa, 6.6 and 158 mg/L at 34 kPa, 7.4 and 240 mg/L at 82 kPa, and 7.4 and 290 mg/L at 117 kPa. Processed ARD alkalinities were correlated to the settled bed depth (p <0.001) and CO2 pressure (p <0.001). Iron, aluminum, and manganese removal efficiencies of 96%, 99%, and 5%, respectively, were achieved with filtration following treatment. No indications of metal hydroxide precipitation or armoring of the limestone were observed. The surplus alkalinity established at 82 kPa was successful in treating an equivalent of 1136 L/min (five-fold dilution) of the combined three ARD streams entering the Toby Creek Plant. This side-stream capability provides savings in treatment unit scale as well as flexibility in treatment effect. The capability of the system to handle higher influent acidity was tested by elevating the acidity to 5000 mg/L with sulfuric acid. Net alkaline effluent was produced, indicating applicability of the process to highly acidic ARD.
Keywords: mine water treatment
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