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Hulshof, A. H. M., Blowes, D. W., & Douglas Gould, W. (2006). Evaluation of in situ layers for treatment of acid mine drainage: A field comparison. Water Res, 40(9), 1816–1826.
Abstract: Reactive treatment layers, containing labile organic carbon, were evaluated to determine their ability to promote sulfate reduction and metal sulfide precipitation within a tailings impoundment, thereby treating tailings effluent prior to discharge. Organic carbon materials, including woodchips and pulp waste, were mixed with the upper meter of tailings in two separate test cells, a third control cell contained only tailings. In the woodchip cell sulfate reduction rates were 500 mg L-1 a-1, (5.2 mmol L-1 a-1) this was coupled with the gradual removal of 350 mg L-1 Zn (5.4 mmol L-1). Decreased δ13CDIC values from -3‰ to as low as -12‰ indicated that sulfate reduction was coupled with organic carbon oxidation. In the pulp waste cell the most dramatic change was observed near the interface between the pulp waste amended tailings and the underlying undisturbed tailings. Sulfate reduction rates were 5000 mg L-1 a-1 (52 mmol L-1 a-1), Fe concentrations decreased by 80–99.5% (148 mmol L-1) and Zn was consistently <5 mg L-1. Rates of sulfate reduction and metal removal decreased as the pore water migrated upward into the shallower tailings. Increased rates of sulfate reduction in the pulp waste cell were consistent with decreased δ13CDIC values, to as low as -22‰, and increased populations of sulfate reducing bacteria. Lower concentrations of the nutrients, phosphorus, organic carbon and nitrogen in the woodchip material contribute to the lower sulfate reduction rates observed in the woodchip cell.
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Zinck, J. (2006). Icard 2006. St. Louis: Proceedings, International Conference of Acid Rock Drainage (ICARD).
Abstract: Sludge management is an escalating concern as the inventory of sludge continues to grow through perpetual “pump and treat” of acidic waters at mine sites. Current sludge management practices, in general, are ad hoc and frequently do not adress long-term storage, and in some cases, long-term stability. While a variety of sludge disposal practices have been applied, many have not been fully investigated and monitoring data on the performance of these technologies is limited and not readily available. This paper discusses options for treatment sludge management including conventionale disposal technologies and options for reclamation of sludge areas.
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Wolkersdorfer, C. (2006). Icard 2006. 7: Proceedings, International Conference of Acid Rock Drainage (ICARD).
Abstract: Acid mine drainage, the drainage of metals, and the prediction of mine water rebound after mine closure are major problems for the mining industry. In the literature, the difficulties in evaluating the hydrodynamics of flooded mines are well described, although only a few tracer tests in flooded mines have been published. Increased knowledge about the hydraulic behaviour of the mine water within a flooded mine might significantly reduce the costs of mine closure and remediation. Relatively cheap and reliable results for decision making can be obtained when tracer tests are properly conducted in a flooded mine prior to planning of remediation strategies or numerical simulations. Applying the results of successful tracer tests allows one to optimise remediation designs and thereby diminish the costs of remediation. The paper summarises the results of several tracer tests and draws general conclusions from such tests.
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Janneck, E., Schlee, K., Arnold, I., & Glombitza, F. (2006). Einsatz neuer Belüftungssysteme zur Effizienzsteigerung bei der Grubenwasserbehandlung in der Lausitz. Wissenschaftliche Mitteilungen, 31, 29–35.
Abstract: Im Beitrag wird über Erfahrungen und Ergebnisse berichtet, wie durch den Einsatz neuer Belüftungssysteme eine deutliche Stabilisierung des Prozesses der Eisenabtrennung in der GWRA Schwarze Pumpe erreicht wurde. Erstmals wurden im Lausitzer Revier Wendelbelüfter im Prozess der Grubenwasserreinigung eingesetzt. Unter Bedingungen, bei denen die Sauerstoffdiffusion der geschwindigkeitsbestimmende Schritt ist, bewirken diese Geräte eine deutliche Beschleunigung der Eisenoxidation. Als zusätzliche Effekte, die zur Effizienzsteigerung der Grubenwasserbehandlung beitragen, können eine wesentliche Durchsatzsteigerung, eine bessere Kalkausnutzung sowie eine deutlich verbes-serte Schlammeindickung genannt werden. The article presents experiences and results of the application of new aerator-systems in the mine water treatment. The processes of ferrous iron oxidation and sludge removal became more stable and efficiently by the application of the aerators. For the first time, spiral aerators were used in the Lower Lusatia lignite mining district to clean ferrous iron containing mine water. These devices lead to an enhanced iron oxidation rate under the existing conditions, where the oxygen diffusion is the rate determining step. Furthermore, the application caused increased throughput, optimal lime utilisation and better sludge thickening, which led to a higher efficiency of the mine water treatment.
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Wiessner, A., Kuschk, P., Buddhawong, S., Stottmeister, U., Mattusch, J., & Kästner, M. (2006). Effectiveness of various small-scale constructed wetland designs for the removal of iron and zinc from acid mine drainage under field conditions. Engineering in Life Sciences, 6(6), 584–592.
Abstract: A system of planted and implanted small-scale SSF (subsurface flow) and SF (surface flow) constructed wetlands together with HP (hydroponic systems) were installed to compare the removal efficiencies of Fe and Zn from AMD (acid mine drainage) under long-term field conditions. Maximum removal of 94 % – 97 % (116 mg/m(exp 2)/d – 142 mg/m(exp 2)/d) for Fe and 69 % – 77 % (6.2 mg/m(exp 2)/d – 7.9 mg/m(exp 2)/d) for Zn was calculated for the planted soil systems. The planted SSF was most sensitive to heavy rain fall. Short-term increases of the metal concentration in the outflows, short-term breakdowns of the Fe removal and continual long-term breakdowns of the Zn removal were observed. In contrast to Zn removal, all wetland types are applicable for Fe removal with maximum removal in the range of 60 % – 98 %. Most of the removed Fe and Zn was transformed and deposited inside the soil bed. The amount absorbed by the plants (0.03 % to 0.3 %) and gravel-associated soil beds (0.03 % to 1.7 %) of the total input were low for both metals. The response of the planted SSF to rainfall suggests a remobilisation of metals accumulated inside the rhizosphere and the importance of buffering effects of the surface water layers of SF systems. The importance of plants for metal removal was shown.
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