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Author Ziemkiewicz, P.F.; Skousen, J.G.; Simmons, J.
Title Long-term Performance of Passive Acid Mine Drainage Treatment Systems Type Journal Article
Year 2003 Publication Mine Water Env. Abbreviated Journal
Volume 22 Issue 3 Pages 118-129
Keywords (up) acidity acid load aerobic wetlands anaerobic wetlands anoxic limestone drains limestone leach beds open limestone channels slag leach beds successive alkalinity producing systems vertical flow wetlands
Abstract State and federal reclamation programs, mining operators, and citizen-based watershed organizations have constructed hundreds of passive systems in the eastern U.S. over the past 20 years to provide reliable, low cost, low maintenance mine water treatment in remote locations. While performance has been reported for individual systems, there has not been a comprehensive evaluation of the performance of each treatment type for a wide variety of conditions. We evaluated 83 systems: five types in eight states. Each system was monitored for influent and effluent flow, pH, net acidity, and metal concentrations. Performance was normalized among types by calculating acid load reductions and removals, and by converting construction cost, projected service life, and metric tonnes of acid load treated into cost per tonne of acid treated. Of the 83 systems, 82 reduced acid load. Average acid load reductions were 9.9 t/yr for open limestone channels (OLC), 10.1 t/yr for vertical flow wetlands (VFW), 11.9 t/yr for anaerobic wetlands (AnW), 16.6 t/yr for limestone leach beds (LSB), and 22.2 t/yr for anoxic limestone drains (ALD). Average costs for acid removal varied from $83/t/yr for ALDs to $527 for AnWs. Average acid removals were 25 g/m2/day for AnWs, 62 g/m2/day for VFWs, 22 g/day/t for OLCs, 28 g/day/t for LSBs, and 56 g/day/t for ALDs. It appears that the majority of passive systems are effective but there was wide variation within each system type, so improved reliability and efficiency are needed. This report is an initial step in determining passive treatment system performance; additional work is needed to refine system designs and monitoring.
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1025-9112 ISBN Medium
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Notes Long-term Performance of Passive Acid Mine Drainage Treatment Systems; 1; FG 1 Abb., 7 Tab.; AMD ISI | Wolkersdorfer Approved no
Call Number CBU @ c.wolke @ 17454 Serial 187
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Author Ordónez, A.; Loredo, J.; Pendás, F.
Title Type Book Whole
Year 1999 Publication Abbreviated Journal
Volume Issue Pages 575-580
Keywords (up) hydrogeology mining water acid mine drainage treatment SAPS successive alkalinity producing system ALD anoxic limestone drainage
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Publisher International Mine Water Association Place of Publication Ii Editor Fernández Rubio, R.
Language Summary Language Original Title
Series Editor Series Title Mine, Water & Environment Abbreviated Series Title
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ISSN ISBN Medium
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Notes A Successive Alkalinity Producing System (SAPS) as operational Unit in a Hybrid Passive Treatment System for Acid Mine Drainage; 1; AMD ISI | Wolkersdorfer; FG 'de' 5 Abb., 4 Tab. Approved no
Call Number CBU @ c.wolke @ 9836 Serial 277
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Author Evangelou, V.P.
Title Pyrite microencapsulation technologies: Principles and potential field application Type Journal Article
Year 2001 Publication Ecological Engineering Abbreviated Journal
Volume 17 Issue 2-3 Pages 165-178
Keywords (up) mine water treatment Acid mine drainage Acidity Alkalinity Amelioration Coating Oxidation Surface reactions
Abstract In nature, pyrite is initially oxidized by atmospheric O2, releasing acidity and Fe2+. At pH below 3.5, Fe2+ is rapidly oxidized by T. ferrooxidans to Fe3+, which oxidizes pyrite at a much faster rate than O2. Commonly, limestone is used to prevent pyrite oxidation. This approach, however, has a short span of effectiveness because after treatment the surfaces of pyrite particles remain exposed to atmospheric O2 and oxidation continuous abiotically. Currently, a proposed mechanism for explaining non-microbial pyrite oxidation in high pH environments is the involvement of OH- in an inner-sphere electron-OH exchange between pyrite/surface-exposed disulfide and pyrite/surface-Fe(III)(OH)n3-n complex and/or formation of a weak electrostatic pyrite/surface-CO3 complex which enhances the chemical oxidation of Fe2+. The above infer that limestone application to pyritic geologic material treats only the symptoms of pyrite oxidation through acid mine drainage neutralization but accelerates non-microbial pyrite oxidation. Therefore, only a pyrite/surface coating capable of inhibiting O2 diffusion is expected to control long-term oxidation and acid drainage production. The objective of this study was to examine the feasibility in controlling pyrite oxidation by creating, on pyrite surfaces, an impermeable phosphate or silica coating that would prevent either O2 or Fe3+ from further oxidizing pyrite. The mechanism underlying this coating approach involves leaching mine waste with a coating solution composed of H2O2 or hypochlorite, KH2PO4 or H4SiO4, and sodium acetate (NaAC) or limestone. During the leaching process, H2O2 or hypochlorite oxidizes pyrite and produces Fe3+ so that iron phosphate or iron silicate precipitates as a coating on pyrite surfaces. The purpose of NaAC or limestone is to eliminate the inhibitory effect of the protons (produced during pyrite oxidation) on the precipitation of iron phosphate or silicate and to generate iron-oxide pyrite coating, which is also expected to inhibit pyrite oxidation. The results showed that iron phosphate or silicate coating could be established on pyrite by leaching it with a solution composed of: (1) H2O2 0.018-0.16 M; (2) phosphate or silicate 10-3 to 10-2 M; (3) coating-solution pH [approximate]5-6; and (4) NaAC as low as 0.01 M. Leachates from column experiments also showed that silicate coatings produced the least amount of sulfate relative to the control, limestone and phosphate treatments. On the other hand, limestone maintained the leachate near neutral pH but produced more sulfate than the control.
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ISSN 0925-8574 ISBN Medium
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Notes July 01; Pyrite microencapsulation technologies: Principles and potential field application; file:///C:/Dokumente%20und%20Einstellungen/Stefan/Eigene%20Dateien/Artikel/10063.pdf; Science Direct Approved no
Call Number CBU @ c.wolke @ 10063 Serial 37
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Author Watzlaf, G.R.; Schroeder, K.T.; Kairies, C.L.
Title Type Book Whole
Year 2000 Publication Abbreviated Journal
Volume Issue Pages 262-274
Keywords (up) passive treatment anoxic limestone drains wetlands sulfate reduction successive alkalinity-producing systems acid mine drainage ALD SAPS RAPS
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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Publisher Place of Publication Tampa Editor
Language Summary Language Original Title
Series Editor Series Title Proceedings, 17th Annual National Meeting – American Society for Surface Mining and Reclamation Abbreviated Series Title
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Notes Long-Term Perpormance of Alkalinity-Producing Passive Systems for the Treatment of Mine Drainage; 2; VORHANDEN | AMD ISI | Wolkersdorfer; als Datei vorhanden 4 Abb., 5 Tab. Approved no
Call Number CBU @ c.wolke @ 17440 Serial 216
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