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Aytas, S. O., Akyil, S., Aslani, M. A. A., & Aytekin, U. (1999). Removal of uranium from aqueous solutions by diatomite (Kieselguhr). Journal of Radioanalytical and Nuclear Chemistry, 240(3), 973–976.
Keywords: acid mine drainage; actinides; adsorption; aqueous solutions; clastic rocks; concentration; decontamination; diatomite; experimental studies; isotherms; laboratory studies; metals; pH; physicochemical properties; pollution; remediation; sedimentary rocks; solutes; sorption; techniques; uranium; uranyl ion; waste disposal; waste water 22, Environmental geology
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Banks, S. B. (2003). The Coal Authority Minewater Treatment Programme: An update on the performance of operational schemes. Land Contam. Reclam., 11(2), 161–164.
Abstract: The performance of mine water treatment schemes, operated under the Coal Authority's national Minewater Treatment Programme, is summarised. Most schemes for which data are available perform successfully and remove over 90% iron. Mean area-adjusted iron removal rates for reedbed components of treatment schemes, range from 1.5 to 5.5 g Fe/m2, with percentage iron removal rates ranging from 68% to 99%. In the majority of cases, calculated area-adjusted removal rates are limited by influent iron loadings, and the empirical sizing criterion for aerobic wetlands, based on American removal rates of 10 g Fe/m2day, remains a valuable tool in the initial stages of treatment system design and estimation of land area requirements. Where a number of schemes have required modification after becoming operational, due consideration must always be given to the potential for dramatic increases in influent iron loadings, and to how the balance between performance efficiency and aesthetic appearance can best be achieved. Continual review and feedback on the performance of treatment systems, and the problems encountered during design implementation, will enhance the efficiency and effectiveness of the Minewater Treatment Programme within the UK.
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Baskin, L. (1979). Linear relationship between mine flow-acid load and influence of depositional environment. In Underground coal mining symposium. New York City: McGraw-Hill.
Keywords: acid mine drainage; Bell Gap Run; Blair County Pennsylvania; Cambria County Pennsylvania; environmental geology; ground water; hydrology; inorganic acids; iron; land use; Little Schuykill River; Loyalsock Creek; metals; Pennsylvania; pollution; programs; pyrite; Randolph County West Virginia; reclamation; rivers and streams; Roaring Creek; Schuylkill County Pennsylvania; statistical analysis; sulfides; sulfuric acid; Sullivan County Pennsylvania; surveys; Swatara Creek; treatment; United States; waste disposal; watersheds; West Virginia 22, Environmental geology
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Benner, S. G., Blowes, D. W., & Ptacek, C. J. (1997). A full-scale porous reactive wall for prevention of acid mine drainage. Ground Water Monitoring and Remediation, 17(4), 99–107.
Abstract: The generation and release of acidic drainage containing high concentrations of dissolved metals from decommissioned mine wastes is an environmental problem of international scale. A potential solution to many acid drainage problem is the installation of permeable reactive walls into aquifers affected by drainage water derived from mine waste materials. A permeable reactive wall installed into an aquifer impacted by low-quality mine drainage waters was installed in August 1995 at the Nickel Rim mine site near Sudbury, Ontario. The reactive mixture, containing organic matter, was designed to promote bacterially mediated sulfate reduction and subsequent metal sulfide precipitation. The reactive wall is installed to an average depth of 12 feet (3.6 m) and is 49 feet (15 m) long perpendicular to ground water flow. The wall thickness (flow path length) is 13 feet (4 m). Initial results, collected nine months after installation, indicate that sulfate reduction and metal sulfide precipitation is occurring. Comparing water entering the wall to treated water existing the wall, sulfate concentrations decrease from 2400 to 4600 mg/L to 200 to 3600 mg/L; Fe concentration decrease from 250 to 1300 mg/L to 1.0 to 40 mg/L, pH increases from 5.8 to 7.0; and alkalinity (as CaCO<inf>3</inf>) increases from 0 to 50 mg/L to 600 to 2000 mg/L. The reactive wall has effectively removed the capacity of the ground water to generate acidity on discharge to the surface. Calculations based on comparison to previously run laboratory column experiments indicate that the reactive wall has potential to remain effective for at least 15 years.
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Benzaazoua, M., & Bussiere, B. (1999). Desulphurization of tailings with low neutralizing potential; kinetic study and flotation modeling. In D. Goldsack, N. Belzile, P. Yearwood, & G. Hall (Eds.), Sudbury '99; Mining and the environment II; conference proceedings.
Abstract: Environmental desulphurization is an attractive alternative for acid generating tailings management as demonstrated during the last few years. In fact, such process placed at the end of the primary treatment circuit allows to reduce greatly the amount of problematic tailings by concentrating the sulphidic fraction. Moreover, the desulphurized tailings (non-acid generating) have the geotechnical and environmental properties for being used as fine material in a cover with capillary barrier effects. To produce desulphurized tailings, non selective froth flotation is the most adapted method as shown in many previous works. Desulphurization level is fixed by tailings sulphur content (or sulphide content) and neutralization potential NP. The final residue should have enough NP to compensate for his acid generating potential AP. In this paper, the authors present the results of laboratory tests conducted in Denver cells for studying the sulphide flotation kinetics of four mine tailings which are characterized by a weak neutralization potential (under 37 kg CaCO (sub 3) /t). Tailings 1, 2, 3 and 4 contain respectively 5.27, 10, 4.25 and 16.9 sulphur Wt. %. Tailings 1 and 2 are cyanide free and are well floated at pH around 11 by using amyl xanthate as collector. Collector dosage was optimized for these tailings and the results show that Tailing 2 need more collector. However, Tailings 3 and 4, which come from a gold cyanidation process, could not provide good sulphide recovery with xanthate collector because of the pyrite depression. To overcome this problem, amine acetate was used successfully but induces important entrainment. The consumption of this collector was also optimized. The results of kinetic tests and collector dosage were combined and modeled to establish relationships which allow to estimate the desulphurization performances.
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