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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Robbins, E. I., Cravotta, C. A., Savela, C. E., & Nord, G. L. (1999). Hydrobiogeochemical Interactions in 'anoxic' Limestone Drains for Neutralization of Acidic Mine Drainage. Fuel, 78(2), 259–270.
Abstract: Processes affecting neutralization of acidic coal mine drainage were evaluated within 'anoxic' limestone drains (ALDs). Influents had pH less than or equal to 3.5 and dissolved oxygen < 2 mg/l. Even though effluents were near neutral (pH > 6 and alkalinity > acidity), two of the four ALDs were failing due to clogging. Mineral-saturation indices indicated the potential for dissolution of calcite and gypsum, and precipitation of Al3+ and Fe3+ compounds. Cleavage mounts of calcite and gypsum that were suspended within the ALDs and later examined microscopically showed dissolution features despite coatings by numerous bacteria, biofilms, and Fe-Al-Si precipitates. In the drain exhibiting the greatest flow reduction, Al-hydroxysulfates had accumulated onlimestone surfaces and calcite etch points, thus causing the decline in transmissivity and dissolution. Therefore, where Al loadings are high and flow rates are low, a pre-treatment step is indicated to promote Al removal before diverting acidic mine water into alkalinity-producing materials. Published by Elsevier Science Ltd.
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Ordónez, A., Loredo, J., & Pendás, F. (1999). (R. Fernández Rubio, Ed.). Mine, Water & Environment. Ii: International Mine Water Association.
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Nairn, R. W., & Hedin, R. S. (1992). Designing wetlands for the treatment of polluted coal mine drainage. In M. C. Landin (Ed.), Wetlands; proceedings of the 13th annual conference; Society of Wetland Scientists (pp. 224–229).
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Miller, S. D. (1999). Overview of acid mine drainage issues and control strategies Remediation and management of degraded lands. In M. H. Wong, J. W. C. Wong, & A. J. M. Baker (Eds.),. Boca Raton: Lewis Publishers.
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