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Yernberg, W. R. (2000). Improvements seen in acid-mine-drainage technology. Min. Eng., 52(9), 67–70.
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Wilmoth, R. C. (1973). Environmental Protection Agency, Technology Series Report. Washington: U.S. Government Print. Offfice.
Abstract: EPA 670 2 73 100 Spiral-wound reverse osmosis systems were tested on four different acid mine drainage discharges in west virginia and pennsylvania. Comparison studies were made of the hollow-fiber, tubular, and spiral-wound systems at a ferrous iron acid discharge; and of hollow-fiber and spiral-wound systems at a ferric iron acid discharge. At all sites, the limiting factor in high recovery operation was calcium sulfate insolubility. An empirical formula was developed for predicting maximum recovery. Application of reverse osmosis was demonstrated to be technically feasible for a large percentage of acid mine drainage discharges. A process called 'neutrolisis' was developed in which the reverse osmosis brine is neutralized and clarified, and the supernatant recycled to the influent to the reverse osmosis unit. In this manner, the neutrolosis process discharges only a high quality product water and a neutralized sludge. Neutrolosis recoveries as high as 98.8 percent were achieved at a ferric iron acid discharge site. (epa)
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Ueki, K., Kotaka, K., Itoh, K., & Ueki, A. (1988). Potential availability of anaerobic treatment with digester slurry of animal waste for the reclamation of acid mine water containing sulfate and heavy metals. Journal of Fermentation Technology, 66(1).
Abstract: The use of an anaerobic digester slurry of cattle waste for the reclamation of acid mine water was examined. When the digester slurry was mixed with acid mine water, anaerobic digestion, including sulfate reduction and methanogenesis, was enhanced. In the mixture of acid mine water and the digester slurry, sulfate reduction proceeded without diminishing methanogenesis. The digester slurry and its supernatant (SDF-sup) showed a significant capacity to act as a strong alkaline reagent, and the pH of the acid mine water was markedly elevated by the addition of the digester slurry of SDF-sup even at the low ratio of 1% (v/v). Precipitation of heavy metals in the acid mine water occurred as the pH was elevated by the addition of SDF-sup. When the digester slurry was added at the ratio of 5% (v/v) to acid mine water which had been pretreated with SDF-sup, the rate of sulfate reduction increased with increasing the concentration of sulfate in the mixture up to about 1,400 mg·l-1. In acid mine water pretreated with SDF-sup and supplemented with the digester slurry at the ratio of 5% (v/v), the maximum amount of sulfate reduced within 20 d of incubation was about 1,000 mg·l-1, and the maximum rate of sulfate reduction was about 120 mg SO42-·l-1·d-1.
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Ye, Z. H., Whiting, S. N., Qian, J. H., Lytle, C. M., Lin, Z. Q., & Terry, N. (2001). Trace element removal from coal ash leachate by a 10-year-old constructed wetland. J. Environ. Qual., 30(5), 1710–1719.
Abstract: This study investigated the ability of a 10-yr-old constructed wetland to treat metal-contaminated leachate emanating from a coal ash pile at the Widows Creek electric utility, Alabama (USA). The two vegetated cells, which were dominated by cattail (Typha latifolia L.) and soft rush (Juncus effusus L.), were very effective at removing Fe and Cd from the wastewater, but less efficient for Zn, S, B, and Mn. The concentrations were decreased by up to 99% for Fe, 91% for Cd, 63% for Zn, 61% for S, 58% for Mn, and 50% for B. Higher pH levels (>6) in standing water substantially improved the removing efficiency of the wetland for Mn only. The belowground tissues of both cattail and soft rush had high concentrations of all elements; only for Mn, however, did the concentration in the shoots exceed those in the belowground tissues. The concentrations of trace elements in fallen litter were higher than in the living shoots, but lower than in the belowground tissues. ne trace element accumulation in the plants accounted for less than 2.5% of the annual loading of each trace element into the wetland. The sediments were the primary sinks for the elements removed from the wastewater. Except for Mn, the concentrations of trace elements in the upper layer (0-5 cm) of the sediment profile tended to be higher than the lower layers (5-10 and 10-15 cm). We conclude that constructed wetlands are still able to efficiently remove metals in the long term (i.e., >10 yr after construction).
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Schueck, J. H. (1995). Limestone diversion wells; a low-maintenance, cost-effective method for treating acid-mine drainage with limestone. In C. R. Carnein, & J. H. Way (Eds.), Guidebook for the Annual Field Conference of Pennsylvania Geologists, vol.60 Applied geology in the Lock Haven and Williamsport region, Clinton and Lycoming counties, northcentral Pennsylvania (pp. 9–12).
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