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Author openurl 
  Title 'Green' company offers desalination technology Type Journal Article
  Year 1998 Publication (down) Water Sewage and Effluent Abbreviated Journal  
  Volume 18 Issue 4 Pages 9-11  
  Keywords Groundwater problems and environmental effects geomechanics abstracts: excavations (77 10 10) acid mine drainage environmental effect mine drainage  
  Abstract Water and wastewater treatment activities, projects and capabilities of South African environmental engineering specialist Envig are detailed. The company, as part of the Weir Wesgarth Consortium, has pre-qualified for the major Namibian Water Supply Project, one of the largest of its kind to date in southern Africa. This project involves the desalination of seawater to meet increasing water demand and shortfalls. Envig, if awarded the contract, would be involved in construction of three or four reverse osmosis or mechanical vapour compression sea water desalination plants and associated infrastructure. The company is also involved in a mine water desalination project at the Eskom Tutuka Power Station. A reverse osmosis plant using low fouling maintenance is being installed to deal with acid mine drainage water. Details of the design and operation of this plant are given.  
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  ISSN 0257-8700 ISBN Medium  
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  Notes 'Green' company offers desalination technology; 0432290; South-Africa; Geobase Approved no  
  Call Number CBU @ c.wolke @ 17548 Serial 496  
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Author Hulshof, A.H.M.; Blowes, D.W.; Douglas Gould, W. url  openurl
  Title Evaluation of in situ layers for treatment of acid mine drainage: A field comparison Type Journal Article
  Year 2006 Publication (down) Water Res Abbreviated Journal  
  Volume 40 Issue 9 Pages 1816-1826  
  Keywords mine water Pollution and waste management non radioactive Groundwater problems and environmental effects acid mine drainage organic carbon oxidation microbial activity drainage groundwater pollution Bacteria microorganisms Contamination Groundwater Barriers Drainage Treatment  
  Abstract Reactive treatment layers, containing labile organic carbon, were evaluated to determine their ability to promote sulfate reduction and metal sulfide precipitation within a tailings impoundment, thereby treating tailings effluent prior to discharge. Organic carbon materials, including woodchips and pulp waste, were mixed with the upper meter of tailings in two separate test cells, a third control cell contained only tailings. In the woodchip cell sulfate reduction rates were 500 mg L-1 a-1, (5.2 mmol L-1 a-1) this was coupled with the gradual removal of 350 mg L-1 Zn (5.4 mmol L-1). Decreased δ13CDIC values from -3‰ to as low as -12‰ indicated that sulfate reduction was coupled with organic carbon oxidation. In the pulp waste cell the most dramatic change was observed near the interface between the pulp waste amended tailings and the underlying undisturbed tailings. Sulfate reduction rates were 5000 mg L-1 a-1 (52 mmol L-1 a-1), Fe concentrations decreased by 80–99.5% (148 mmol L-1) and Zn was consistently <5 mg L-1. Rates of sulfate reduction and metal removal decreased as the pore water migrated upward into the shallower tailings. Increased rates of sulfate reduction in the pulp waste cell were consistent with decreased δ13CDIC values, to as low as -22‰, and increased populations of sulfate reducing bacteria. Lower concentrations of the nutrients, phosphorus, organic carbon and nitrogen in the woodchip material contribute to the lower sulfate reduction rates observed in the woodchip cell.  
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  ISSN 0043-1354 ISBN Medium  
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  Notes May; Evaluation of in situ layers for treatment of acid mine drainage: A field comparison; file:///C:/Dokumente%20und%20Einstellungen/Stefan/Eigene%20Dateien/Artikel/10040.pdf; Science Direct Approved no  
  Call Number CBU @ c.wolke @ 10040 Serial 49  
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Author Smith, I.J.H. openurl 
  Title AMD treatment, it works but are we using the right equipment? Type Journal Article
  Year 2000 Publication (down) Tailings and mine waste ' Abbreviated Journal  
  Volume Issue Pages 419-427  
  Keywords Groundwater problems and environmental effects geomechanics abstracts: excavations (77 10 10) acid mine drainage conference proceedings methodology mine drainage remediation waste management  
  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).  
  Address J.H. Smith III, SEPCO Incorporated, Fort Collins, CO, United States  
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  Notes Book; Conference-Paper; AMD treatment, it works but are we using the right equipment?; 2263351; Using Smart Source Parsing 00-Proceedings-of-the-7th-international-conference-Fort-Collins-January- 2000 Netherlands; Geobase Approved no  
  Call Number CBU @ c.wolke @ 17541 Serial 237  
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Author Benzaazoua, M.; Bussiere, B. isbn  openurl
  Title Desulphurization of tailings with low neutralizing potential; kinetic study and flotation modeling Type Book Chapter
  Year 1999 Publication (down) Sudbury '99; Mining and the environment II; conference proceedings Abbreviated Journal  
  Volume Issue Pages  
  Keywords acid mine drainage chemical properties chemical reactions environmental analysis environmental effects experimental studies flotation geochemistry kinetics laboratory studies mathematical models neutralization pH pollution sulfur tailings 22 Environmental geology 02A General geochemistry  
  Abstract Environmental desulphurization is an attractive alternative for acid generating tailings management as demonstrated during the last few years. In fact, such process placed at the end of the primary treatment circuit allows to reduce greatly the amount of problematic tailings by concentrating the sulphidic fraction. Moreover, the desulphurized tailings (non-acid generating) have the geotechnical and environmental properties for being used as fine material in a cover with capillary barrier effects. To produce desulphurized tailings, non selective froth flotation is the most adapted method as shown in many previous works. Desulphurization level is fixed by tailings sulphur content (or sulphide content) and neutralization potential NP. The final residue should have enough NP to compensate for his acid generating potential AP. In this paper, the authors present the results of laboratory tests conducted in Denver cells for studying the sulphide flotation kinetics of four mine tailings which are characterized by a weak neutralization potential (under 37 kg CaCO (sub 3) /t). Tailings 1, 2, 3 and 4 contain respectively 5.27, 10, 4.25 and 16.9 sulphur Wt. %. Tailings 1 and 2 are cyanide free and are well floated at pH around 11 by using amyl xanthate as collector. Collector dosage was optimized for these tailings and the results show that Tailing 2 need more collector. However, Tailings 3 and 4, which come from a gold cyanidation process, could not provide good sulphide recovery with xanthate collector because of the pyrite depression. To overcome this problem, amine acetate was used successfully but induces important entrainment. The consumption of this collector was also optimized. The results of kinetic tests and collector dosage were combined and modeled to establish relationships which allow to estimate the desulphurization performances.  
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  Publisher Place of Publication Editor Goldsack, D.; Belzile, N.; Yearwood, P.; Hall, G.  
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  ISSN ISBN 0886670470 Medium  
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  Notes Desulphurization of tailings with low neutralizing potential; kinetic study and flotation modeling; GeoRef; English; 2002-060841; Sudbury '99; Mining and the environment II--Sudbury '99; L'exploitation miniere et l'environnement, Sudbury, ON, Canada, Sept. 13-17, 1999 References: 26; illus. incl. 5 tables Approved no  
  Call Number CBU @ c.wolke @ 16572 Serial 452  
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Author Ntengwe, F.W. url  openurl
  Title An overview of industrial wastewater treatment and analysis as means of preventing pollution of surface and underground water bodies – The case of Nkana Mine in Zambia Type Journal Article
  Year 2005 Publication (down) Phys. Chem. Earth Abbreviated Journal  
  Volume 30 Issue 11-16 Spec. Iss. Pages 726-734  
  Keywords mine water treatment Groundwater problems and environmental effects Pollution and waste management non radioactive geomechanics abstracts: excavations (77 10 10) geological abstracts: environmental geology (72 14 2) wastewater pollution control acid mine drainage Hyacinthus Zambia Southern Africa Sub Saharan Africa Africa Eastern Hemisphere World  
  Abstract The wastewaters coming from mining operations usually have low pH (acidic) values and high levels of metal pollutants depending on the type of metals being extracted. If unchecked, the acidity and metals will have an impact on the surface water. The organisms and plants can adversely be affected and this renders both surface and underground water unsuitable for use by the communities. The installation of a treatment plant that can handle the wastewaters so that pH and levels of pollutants are reduced to acceptable levels provides a solution to the prevention of polluting surface and underground waters and damage to ecosystems both in water and surrounding soils. The samples were collected at five points and analyzed for acidity, total suspended solids, and metals. It was found that the pH fluctuated between pH 2 when neutralization was forgotten and pH 11 when neutralization took place. The levels of metals that could cause impacts to the water ecosystem were found to be high when the pH was low. High levels of metals interfere with multiplication of microorganisms, which help in the natural purification of water in stream and river bodies. The fish and hyacinth placed in water at the two extremes of pH 2 and pH 11 could not survive indicating that wastewaters from mining areas should be adequately treated and neutralized to pH range 6-9 if life in natural waters is to be sustained. < copyright > 2005 Elsevier Ltd. All rights reserved.  
  Address F.W. Ntengwe, Copperbelt University, School of Technology, P.O. Box 21692, Kitwe, Zambia fntengwe@cbu.ac.zm  
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  ISSN 1474-7065 ISBN Medium  
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  Notes Review; An overview of industrial wastewater treatment and analysis as means of preventing pollution of surface and underground water bodies – The case of Nkana Mine in Zambia; 2790318; United-Kingdom 23; file:///C:/Dokumente%20und%20Einstellungen/Stefan/Eigene%20Dateien/Artikel/10301.pdf; Geobase Approved no  
  Call Number CBU @ c.wolke @ 17497 Serial 24  
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