Stewart, D., Norman, T., Cordery-Cotter, S., Kleiner, R., Sweeney, E., & Nelson, J. D. (1997). Utilization of a ceramic membrane for acid mine drainage treatment. Tailings and Mine Waste '97, , 453–460.
Abstract: BASX Systems LLC has developed a treatment system based on ceramic membranes for the removal of heavy metals from an acid mine drainage stream. This stream also contained volatile organic compounds that were required to be removed prior to discharge to a Colorado mountain stream. The removal of heavy metals was greater than 99% in most cases. A decrease of 30% in chemicals required for treatment and a reduction by more than 75% in labor over a competing technology were achieved. These decreases were obtained for operating temperatures of less than 5 degrees C. This system of ceramic microfiltration is capable of treating many different types of acid mine waste streams for heavy metals removal.
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Smyth, D. J. A., Blowes, D. W., Benner, S. G., Hulshof, A. M., & Nelson, J. D. (2001). In situ treatment of groundwater impacted by acid mine drainage using permeable reactive materials. In Proceedings of the Eighth international conference on Tailings and mine waste '01 (pp. 313–322).
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Smith, I. J. H. (2000). AMD treatment, it works but are we using the right equipment? Tailings and mine waste ', , 419–427.
Abstract: For the past 40 years various approaches have been developed to treat acid waters coming from abandoned as well as operating mining operations. System designs have evolved to meet increasingly stringent discharge permit limits for treated water, as well as to provide solid disposal within economic constraints. A treatment system for remediation of acid mine drainage (AMD) or acid groundwater (AG) requires two main steps: 1. The addition of chemicals to precipitate dissolved metals contained in the waters, and if necessary, to coagulate the precipitated solids ahead of physical separation. 2. Physical separation of the precipitated solids from the water so the water can be lawfully discharged from the site. Choosing the appropriate technology and equipment results in the most efficient plant design, the lowest capital outlay, and minimum operating cost. The goal of these plants is to discharge liquids and solids able to meet standards. The separation of solids from liquids can be achieved through various means, including gravity settling, flotation, mechanical dewatering, filtration and evaporation. As important as the liquid solids separation unit operations are, they are driven by the chemistry of the water to be treated. The content of the dissolved solids will influence the quality and quantity of the solids produced during precipitation. Thus the two aspects must be integrated, with chemistry first, then mechanical engineering. This presentation will provide an overview of a number of liquid solids separation tools currently being used to treat AMD-AG at several sites in the USA. It will also discuss how their operations are impacted by the chemistry of their particular acid water feeds. The tools used include clarifier-thickeners, solids contact clarifiers, dissolved air flotation, polishing filters, membrane filters, and mechanical dewatering devices (belt and filter presses, vacuum filters, and driers).
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Naugle, W. K. (2003). Remediation of the Eagle Mine superfund site: a biological success story. Tailings and Mine Waste '03, , 481–485.
Abstract: Remediation of the Eagle Mine Superfund Site began in 1988. Remedial action included: bulk-heading adits, flooding mine workings; constructing diversion ditches around waste rock; consolidating mine wastes in an on-site tailings pile; capping the tailings pile with a multi-layer, engineered cap; and revegetating disturbed areas with native plants. Flooding the mine workings resulted in unacceptable seepage into the Eagle River in late 1989. A water treatment plant was constructed to collect mine seepage and groundwater at the main tailings pile. In October 2001, construction of the remedy was declared “complete” and the site is now in the operation, maintenance and monitoring phase. A strong downward trend in zinc and cadmium concentrations in the Eagle River has occurred and, trout and macroinvertebrate populations have increased. Biological data are being used to establish water quality standards for the Eagle River.
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Harrington, J. M. (2002). In situ treatment of metals in mine workings and materials. Tailings and Mine Waste '02, , 251–261.
Abstract: Contact of oxygen contained in air and water with mining materials can increase the solubility of metals. In heaps leached by cyanide, metals can also be made soluble through complexation with cyanide. During closure, water in heaps, and water collected in mine workings and pit lakes may require treatment to remove these metals. In situ microbiological treatment to create reductive conditions and to precipitate metals as sulfides or elemental metal has been applied at several sites with good success. Treatment by adding organic carbon to stimulate in situ microbial reduction has been successful in removing arsenic, cadmium, chromium, copper, iron, lead, manganese, mercury, nickel, selenium, silver, tin, uranium, and zinc to a solid phase. Closure practices can affect the success of in situ treatment at mining sites, and affect the stability of treated materials. This paper defines factors that determine the cost and permanence of in situ treatment.
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