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Weeks, R. E., Krohn, R., & Walker, T. H. (2000). Water management during the Pinto Valley removal action. In Tailings and Mine and Waste 2000, Proceedings of the Seventh International Conference, Fort Collins, US, Jan 22 26, 2000 (pp. 499–506).
Abstract: Der Bruch des Dammes einer Halde der Grube Nr. 14 des Kupfer- Bergbaubetriebes Pinto Valley in Arizona, USA, im Jahre 1997 führte zum Eintrag von 370000 yd(exp 3) Bergematerials und Tailings in das Bett des Flusses Pinto Creek, USA, wodurch letzteres blockiert wurde. Der Vorfall ereignete sich in bergigem Gelände unterhalb eines 14 Quadratmeilen großen Abschnittes des Flusseinzugsgebietes oberhalb des Sees Roosevelt Lake, USA, einer Trinkwasserquelle für Phoenix, USA. Aufgrund der Bedeutung des Gebietes wurde eine Strategie zur Verhütung weiterer Beeinträchtigungen der Wasserqualität ausgearbeitet. Diese beinhaltete Managementaspekte zur Gewährleistung einer schnellen Planung und Ausführung der notwendigen Arbeiten gekoppelt mit der Planung, dem Bau und dem Betrieb von Rückhalte und Umleitungssystemen für auftretende Wässer. Die Auslegung dieser Systeme erfolgte auf der Grundlage der Daten des Einzugsgebietes und der klimatischen Verhältnisse, wobei verschiedene Wahrscheinlichkeiten der Überschreitung der ermittelten Werte berücksichtigt wurden. Innerhalb von acht Monaten konnten die Tailings aus dem betroffenen Gebiet entfernt werden, ohne dass belastete Oberflächenwässer freigesetzt wurden.
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Watzlaf, G. R., Schroeder, K. T., & Kairies, C. L. (2000). Proceedings, 17th Annual National Meeting – American Society for Surface Mining and Reclamation. Tampa.
Abstract: Ten passive treatment systems, located in Pennsylvania and Maryland, have been intensively monitored for up to ten years. Influent and effluent water quality data from ten anoxic limestone drains (ALDs) and six reducing and alkalinity-producing systems (RAPS) have been analyzed to determine long-term performance for each of these specific unit operations. ALDs and RAPS are used principally to generate alkalinity, ALDs are buried beds of limestone that add alkalinity through dissolution of calcite. RAPS add alkalinity through both limestone dissolution and bacterial sulfate reduction. ALDs that received mine water containing less than 1 mg/L of both ferric iron and aluminum have continued to produce consistent concentrations of alkalinity since their construction. However, an ALD that received 20 mg/L of aluminum experienced a rapid reduction in permeability and failed within five months. Maximum levels of alkalinity (between 150 and 300 m&) appear to be reached after I5 hours of retention. All but one RAPS in this study have been constructed and put into operation only within the past 2.5 to 5 years. One system has been in operation and monitored for more than nine years. AIkalinity due to sulfate reduction was highest during the first two summers of operation. Alkalinity due to a limestone dissolution has been consistent throughout the life of the system. For the six RAPS in this study, sulfate reduction contributed an average of 28% of the total alkalinity. Rate of total alkalinity generation range from 15.6 gd''rn-'to 62.4 gd-'mL2 and were dependent on influent water quality and contact time.
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Stoica, L., & Dima, G. (2000). Pb(II) removal from aqueous systems by biosorption-flotation on mycelial residues of Penicillium chrysogenum. In A. Rozkowski (Ed.), 7th international Mine Water Association congress; Mine water and the environment (pp. 472–481). Sosnowiec: Uniwersytet Slaski.
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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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Skousen, J. G., Sexstone, A., & Ziemkiewicz, P. F. (2000). (I. Barnhisel Richard, G. Darmody Robert, & W. L. Daniels, Eds.). Reclamation of Drastically Disturbed Lands. Madison, Wis.: American Society of Agronomy.
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