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Rammlmair, D., & Grissemann, C. (2000). Natural attenuation in slag heaps versus remediation. In D. Rammlmair, J. Mederer, T. Oberthuer, R. B. Heimann, & H. J. Pentinghaus (Eds.), Applied mineralogy in research, economy, technology, ecology and culture (pp. 645–648).
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Sato, D., & Tazaki, K. (2000). Calcification treatment of mine drainage and depositional formula of heavy metals. Chikyu Kagaku = Earth Science, 54(5), 328–336.
Abstract: Depositional formula of heavy metals after disposal of the mine drainage from the Ogoya Mine in Ishikawa Prefecture, Japan, was mineralogically investigated. Strong acidic wastewater (pH 3.5) from pithead of the mine contains high concentration of heavy metals. In this mine, neutralizing coagulation treatment is going on by slaked lime (calcium hydroxides: Ca(OH) (sub 2) ). Core samples were collected at disposal pond to which the treated wastewater flows. The core samples were divided into 44 layers based on the color variation. The mineralogical and chemical compositions of each layer were analyzed by an X-ray powder diffractometer (XRD), an energy dispersive X-ray fluorescence analyzer (ED-XRF) and a NCS elemental analyzer. The upper parts are rich in brown colored layers, whereas discolored are the deeper parts. The color variation is relevant to Fe concentration. Brown colored core sections are composed of abundant hydrous ferric oxides with heavy metals, such as Cu, Zn, and Cd. On the other hand, S concentration gradually increases with depth. XRD data indicated that calcite decreases with increasing depth, and ettringite is produced at the deeper parts. Cd concentration shows similar vertical profile to those of calcite and ettringite. The results revealed that hydrous ferric oxides, calcite and ettringite are formed on deposition, whereby incorporating the heavy metals.
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Zinck, J. M., & Aube, B. C. (2000). Optimization of lime treatment processes. CIM Bull., 93(1043), 98–105.
Abstract: Lime neutralization technology is widely used in Canada for the treatment of acid mine drainage and other acidic effluents. In many locations, improvements to the lime neutralization process are necessary to achieve a maximum level of sludge densification and stability. Conventional lime neutralization technology effectively removes dissolved metals to below regulated limits. However, the metal hydroxide and gypsum sludge generated is voluminous and often contains less than 5% solids. Despite recent improvements in the lime neutralization technology, each year, more than 6 700 000 m3 of sludge are generated by treatment facilities operated by the Canadian mining industry. Because lime neutralization is still seen as the best available approach for some sites, sludge production and stability are expected to remain as issues in the near future. Several treatment parameters significantly impact operating costs, effluent quality, sludge production and the geochemical stability of the sludge. Studies conducted both at CANMET and NTC have shown that through minor modifications to the treatment process, plant operators can experience a reduction in operating costs, volume of sludge generated, metal release to the environment and liability. This paper discusses how modifications in plant operation and design can reduce treatment costs and liability associated with lime treatment.
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Fripp, J., Ziemkiewicz, P. F., & Charkavorki, H. (2000). Acid Mine Drainage Treatment. Ecosystem Management and Restoration Research Program Technical Notes, Erdc Tn-Emrrp-Sr-14, 7.
Abstract: Contaminated water flowing from abandoned coal mines is one of the most significant contributors to water pollution in former and current coal-producing areas. Acid mine drainage (AMD) can have severe impacts to aquatic resources, can stunt terrestrial plant growth and harm wetlands, contaminate groundwater, raise water treatment costs, and damage concrete and metal structures. In the Appalachian Mountains of the eastern United States alone, more than 7,500 miles of streams are impacted. The Pennsylvania Fish and Boat Commission estimates that the economic losses on fisheries and recreational uses are approximately $67 million annually (ref). While most modern coal-mining operations (Figure 1) must meet strict environmental regulations concerning mining techniques and treatment practices, there are thousands of abandoned mine sites in the United States (Figure 2). Treatment of a single site can result in the restoration of several miles of impacted streams. The purpose of this document is to briefly summarize key issues related to AMD treatment. This document is intended as a brief overview; thus, it is neither inclusive nor exhaustive. The technical note presents the preliminary planning issues
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Mitchell, P. (2000). Silica micro encapsulation: An innovative commercial technology for the treatment of metal and radionuclide contamination in water and soil. Environmental Issues and Management of Waste in Energy and Mineral Production, , 307–314.
Abstract: Klean Earth Environmental Company (KEECO) has developed the Silica Micro Encapsulation (SME) technology to treat heavy metals and radionuclides in water and soil. Unlike conventional neutralization/precipitation methods, SME encapsulates the contaminants in a permanent silica matrix resistant to degradation under even extreme environmental conditions. Encapsulated metals and radionuclides are effectively immobilized, minimising the potential for environmental contamination and impacts on human or ecosystem health. The effectiveness of SME has been proven through independent reviews, laboratory and field trials and commercial contracts, and the technology can be used to control and prevent acid drainage and the transport of soluble metals from mine sites, tailings areas, landfills and industrial sites. Successful demonstrations in the treatment of sediments and in brownfield redevelopment, treatment of metal-finishing wastewaters, and control of hazardous, low-level, and mixed waste at DOE/DOD sites and commercial nuclear power plants have also been undertaken. This paper describes the reactions involved in the SME process, the methods by which SME chemicals are introduced to various media, and recent project applications relevant to the cost effective remediation and prevention of environmental problems arising from energy and mineral production.
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