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Author Watzlaf, G.R.; Schroeder, K.T.; Kairies, C.L.
Title Type (up) Book Whole
Year 2000 Publication Abbreviated Journal
Volume Issue Pages 262-274
Keywords 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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Corporate Author Thesis
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
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
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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Author Stewart, B.R.
Title The influence of fly ash additions on acid mine drainage production from coarse coal refuse Type (up) Book Whole
Year 1996 Publication Abbreviated Journal
Volume Issue Pages
Keywords acid mine drainage; acidic composition; alkalic composition; alkalinity; ash; coal; controls; copper; diffusion; dissolved materials; experimental studies; geologic hazards; hydraulic conductivity; iron; leachate; leaching; manganese; metals; organic residues; oxidation; oxygen; pH; pollutants; pollution; sedimentary rocks; soil treatment; soils; sorption; sulfate ion; waste disposal; water quality 22, Environmental geology
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Corporate Author Thesis Ph.D. thesis
Publisher Virginia Polytechnic Institute and State University, Place of Publication Blacksburg Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes The influence of fly ash additions on acid mine drainage production from coarse coal refuse; GeoRef; English Approved no
Call Number CBU @ c.wolke @ 6351 Serial 230
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Author Ordónez, A.; Loredo, J.; Pendás, F.
Title Type (up) Book Whole
Year 1999 Publication Abbreviated Journal
Volume Issue Pages 575-580
Keywords 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
Area Expedition Conference
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 (up) Journal Article
Year 2001 Publication Ecological Engineering Abbreviated Journal
Volume 17 Issue 2-3 Pages 165-178
Keywords 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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Series Editor Series Title Abbreviated Series Title
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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 Kepler, D.A.; Mc Cleary, E.C.
Title Successive Alkalinity-Producing Systems (SAPS) for the Treatment of Acid Mine Drainage Type (up) Journal Article
Year 1994 Publication Proceedings, International Land Reclamation and Mine Drainage Conference Abbreviated Journal
Volume 1 Issue Pages 195-204
Keywords acid mine drainage; alkalinity; anaerobic environment; calcium carbonate; chemical reactions; experimental studies; pH; pollutants; pollution; remediation; water quality SAPS mine water RAPS
Abstract Constructed wetland treatment system effectiveness has been limited by the alkalinity-producing, or acidity-neutralizing, capabilities of systems. Anoxic limestone drains (ALD's) have allowed for the treatment of approximately 300 mg/L net acidic mine drainage, but current design guidance precludes using successive ALD's to generate alkalinity in excess of 300 mg/L because of concerns with dissolved oxygen. “Compost” wetlands designed to promote bacterially mediated sulfate reduction are suggested as a means of generating alkalinity required in excess of that produced by ALD's. Compost wetlands create two basic needs of sulfate reducing bacteria; anoxic conditions resulting from the inherent oxygen demand of the organic substrate, and quasi-circumneutral pH values resulting from the dissolution of the carbonate fraction of the compost. However, sulfate reduction treatment area needs are generally in excess of area availability and/or cost effectiveness. Second generation alkalinity-producing systems demonstrate that a combination of existing treatment mechanisms has the potential to overcome current design concerns and effectively treat acidic waters ad infinitum. Successive alkalinity-producing systems (SAPS) combine ALD technology with sulfate reduction mechanisms. SAPS promote vertical flow through rich organic wetland substrates into limestone beds beneath the organic compost, discharging the pore waters. SAPS allow for conservative wetland treatment sizing calculations to be made as a rate function based on pH and alkalinity values and associated contaminant loadings. SAPS potentially decrease treatment area requirements and have the further potential to generate alkalinity in excess of acidity regardless od acidity concentrations.
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Series Editor Series Title Abbreviated Series Title
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Notes Successive Alkalinity-Producing Systems (SAPS) for the Treatment of Acid Mine Drainage; Cn, Kj, Aj; file:///C:/Dokumente%20und%20Einstellungen/Stefan/Eigene%20Dateien/Artikel/9722.pdf; AMD ISI | Wolkersdorfer Approved no
Call Number CBU @ c.wolke @ 9722 Serial 55
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