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LaPointe, F., Fytas, K., & McConchie, D. (2005). Using permeable reactive barriers for the treatment of acid rock drainage. International journal of surface mining, reclamation and environment, 19(1), 57–65.
Abstract: Acid mine drainage (AMD) is the most serious environmental problem facing the Canadian mineral industry today. It results from oxidation of sulphide minerals (e.g. pyrite or pyrrhotite) contained in mine waste or mine tailings and is characterized by acid effluents rich in heavy metals that are released into the environment. A new acid remediation technology is presented, by which metallurgical residues from the aluminium extraction industry are used to construct permeable reactive barriers (PRBs) to treat acid mine effluents. This technology is very promising for treating acid mine effluents in order to decrease their harmful environmental effects
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Botha, G. R., Sanderson, R. D., & Buckley, C. A. (1992). Brief Historical Review of Membrane-development and Membrane Applications in Waste-water Treatment in Southern Africa. Water Sci. Technol., 25(10), 1–4.
Abstract: Away back in 1953 few people in the world, let alone South Africa, knew or had heard about membrane desalination, but there was an increasing awareness that electrodialysis had considerable potential for the desalination of brackish water.In South Africa the development of the new gold fields in the northern Orange Free State and the problems posed by the presence of excessive volumes of very saline mine waters stimulated interest in desalination and the CSIR* in collaboration with the mining industry became involved in the development of the electrodialysis process. By 1959 the largest brackish desalination plant in the world had been built and commissioned. South Africans were thus in the forefront of this technology, even to the extent of making the required membranes locally.Our historical review of membrane development and the applications of membrane technology in Southern Africa encompasses both pressure- and voltage-driven processes. Examples of the pressure processes are microfiltration, ultrafiltration and charged membrane ultrafiltration or nanofiltration, and finally reverse osmosis with fixed and dynamically formed membranes. The voltage-drive processes considered are electrodialysis and electrodialysis reversal.
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Orava, D. A., & Swider, R. C. (1996). Inhibiting acid mine drainage throughout the mine life cycle. CIM Bull., 89(999), 52–56.
Abstract: The technical knowledge and practical experience accumulated by industry and others in abating acid mine drainage (AMD) is being proactively applied at every phase of the mine life cycle. This paper traces the mine life cycle from exploration to post closure monitoring and maintenance, and reviews AMD abatement measures that have become an integral component of exploration and mining activities. Attention is increasingly being given to evaluating AMD potential as part of exploration work, and studies related to project feasibility and design. Mining, mineral processing and waste management options are selected taking into consideration their suitability to inhibit AMD. These inhibition measures are typically committed to in closure plans submitted at the permitting stage. Mines are operated and decommissioned, often progressively, as planned and in accordance with environmental protection policies. Es wird über das Problem der Säurebildung aus sulfidischen Aufbereitungsbergen und taubem Gestein im Verlauf des Existenzzyklus eines Bergwerkes berichtet. In Kanada werden seit etwa 10 Jahren intensive Forschungen für Vorhersage, Kontrolle und Eindämmung von Saürebildungen im Bergbau betrieben. Schwerpunkt ist dabei die sulfidische Oxidation (2FeS2 + 7O2 = 2FeSO4 + 2H2SO4) unter Einwirkung verschiedener physikalischer, geochemischer und biologischer Faktoren. Diese Reaktion führt zu einem Komplex weiterer chemischer Reaktionen unter Bildung von zusätzlicher Säure und Lösung von Metallen. Daraus ergeben sich zwei Hauptmöglichkeiten diesen Prozeß zu steuern: 1. die Sulfidoxidation verhindern, 2. den Oxidationsprozeß verlangsamen. Mit dem heutigen Wissensstand ist es möglich, das Säurebildungspotential von Aufbereitungsbergen zu bestimmen, den Prozeß der Sulfidoxidation von Mineralen unter bestimmten physikalischen, geochemischen und biologischen Bedingungen zu modellieren und die Säurebildung von Aufbereitungsbergen und sulfidischen Gesteinen einzudämmen. Im einzelnen werden Maßnahmen zur Bewertung des Säurebildungspotentials und zur Kontrolle und Reduzierung dieses Prozesses während der Existenzstadien Exploration, Durchführbarkeitsstudie und Genehmigung, Gewinnung und Stillegung eines Bergwerkes erläutert. An Beispielen wird gezeigt, daß bei rechtzeitgem Erkennen des Säurebildungspotentials in der Phase der Exploration Verfahren und Maßnahmen bezüglich Aufbereitung, Umgang mit Aufbereitungsbergen ausgewählt werden können.
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Berthelot, D., Haggis, M., Payne, R., McClarty, D., & Courtain, M. (1999). Application of water covers, remote monitoring and data management systems to environmental management at uranium tailings sites in the Serpent River Watershed. CIM Bull., 92(1033), 70–77.
Abstract: Over forty years of uranium mining in the Elliot lake region of Ontario (1956-1996) has resulted in the production of over 300 million pounds of uranium. With the completion of mining activity Rio Algom limited and Denison Mines limited are utilizing progressive environmental technologies and management systems to reduce and manage the environmental risks associated with the 150 million tonnes of potentially acid-generating tailings in nine regional waste management areas. Water covers designed to reduce oxygen entry and, thereby, significantly inhibit acid generation, have been applied at six of the sites with the Quirke site serving as a demonstration site for the Mine Environmental Neutral Drainage program, All five of Rio Algom limited's effluent treatment plants are monitored and controlled from a central control station utilizing a Supervisory Control and Data Acquisition (SCADA) system based on “Fix Dmacs” technology Scheduling, auditing and reporting of plant operating and environmental monitoring programs for the entire watershed are controlled utilizing the Regional Environmental Information Management System (REIMS). Proper application of these technologies and management systems facilitates delivery of cost-effective environmental monitoring, care and maintenance programs at these sites and provides tools to demonstrate compliance with all environmental performance criteria.
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Kuyucak, N. (2002). Acid mine drainage prevention and control options. CIM Bull., 95(1060), 96–102.
Abstract: Acid mine drainage (AMD) is one of the most significant environmental challenges facing the mining industry worldwide. It occurs as a result of natural oxidation of sulphide minerals contained in mining wastes at operating and closed/decommissioned mine sites. AMD may adversely impact the surface water and groundwater quality and land use due to its typical low pH, high acidity and elevated concentrations of metals and sulphate content. Once it develops at a mine, its control can be difficult and expensive. If generation of AMD cannot be prevented, it must be collected and treated. Treatment of AMD usually costs more than control of AMD and may be required for many years after mining activities have ceased. Therefore, application of appropriate control methods to the site at the early stage of the mining would be beneficial. Although prevention of AMD is the most desirable option, a cost-effective prevention method is not yet available. The most effective method of control is to minimize penetration of air and water through the waste pile using a cover, either wet (water) or dry (soil), which is placed over the waste pile. Despite their high cost, these covers cannot always completely stop the oxidation process and generation of AMD. Application of more than one option might be required. Early diagnosis of the problem, identification of appropriate prevention/control measures and implementation of these methods to the site would reduce the potential risk of AMD generation. AMD prevention/control measures broadly include use of covers, control of the source, migration of AMD, and treatment. This paper provides an overview of AMD prevention and control options applicable for developing, operating and decommissioned mines.
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