| |
Records |
Links |
|
Author |
Hulshof, A.H.M.; Blowes, D.W.; Douglas Gould, W. |
|
| |
Title |
Evaluation of in situ layers for treatment of acid mine drainage: A field comparison |
Type |
Journal Article |
| |
Year |
2006 |
Publication |
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. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0043-1354 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
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 |
|
| Permanent link to this record |
| |
|
| |
|
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 |
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. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0925-8574 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
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 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Foucher, S.; Battaglia-Brunet, F.; Ignatiadis, I.; Morin, D. |
|
| |
Title |
Treatment by sulfate-reducing bacteria of Chessy acid-mine drainage and metals recovery |
Type |
Journal Article |
| |
Year |
2001 |
Publication |
Chemical Engineering Science |
Abbreviated Journal |
|
|
| |
Volume |
56 |
Issue |
4 |
Pages |
1639-1645 |
|
| |
Keywords |
Acid mine drainage Sulfate-reducing bacteria Sulfide precipitation Hydrogen transfer Fixed bed column reactor |
|
| |
Abstract |
Acid-mine drainage can contain high concentrations of heavy metals and release of these contaminants into the environment is generally avoided by lime neutralization. However, this classical treatment is expensive and generates large amounts of residual sludge. The selective precipitation of metals using H2S produced biologically by sulfate-reducing bacteria has been proposed as an alternative process. Here, we report on experiments using real effluent from the disused Chessy-les-Mines mine-site at the laboratory pilot scale. A fixed-bed bioreactor, fed with an H2/CO2 mixture, was used in conjunction with a gas stripping column. The maximum rate of hydrogen transfer in the bioreactor was determined before inoculation. kLa was deduced from measurements of O2 using Higbie and Danckwert's models which predict a dependence on diffusivity. The dynamic method of physical absorption and desorption was used. The maximum rate of H2 transfer suggests that this step should not be a limiting factor. However, an increase in H2 flow rate was observed to induce an increase in sulfate reduction rate. For the precipitation step, the gas mixture from the bioreactor was bubbled into a stirred reactor fed with the real effluent. Cu and Zn could be selectively recovered at pH=2.8 and pH=3.5, respectively. Other impurities such as Ni and Fe could also be removed at pH=6 by sulfide precipitation. Part of the outlet stream from the bioreactor was used to regulate and maintain the pH during sulfide precipitation by feeding the outlet stream back into the bioreactor. The replacement of synthetic medium with real effluent had a positive effect on sulfate reduction rate which increased by 30-40%. This improvement in bacterial efficiency may be related to the large range of oligo-elements provided by the mine-water. The maximum sulfate reduction rate observed with the real effluent was 200 mgl-1 h-1, corresponding to a residence time of 0.9 day. A preliminary cost estimation based on a treatment rate of 5 m3 h-1 of a mine effluent containing 5 gl-1 SO42- is presented. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0009-2509 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Feb.; Treatment by sulfate-reducing bacteria of Chessy acid-mine drainage and metals recovery; file:///C:/Dokumente%20und%20Einstellungen/Stefan/Eigene%20Dateien/Artikel/10064.pdf; Science Direct |
Approved |
no |
|
| |
Call Number |
CBU @ c.wolke @ 10064 |
Serial |
54 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Johnson, D.B.; Hallberg, K.B. |
|
| |
Title |
Pitfalls of passive mine water treatment |
Type |
Journal Article |
| |
Year |
2002 |
Publication |
Reviews in Environmental Science & Biotechnology |
Abbreviated Journal |
|
|
| |
Volume |
1 |
Issue |
5 |
Pages |
335-343 |
|
| |
Keywords |
acid mine drainage acidophilic microorganisms heavy metals iron oxidation iron reduction remediation sulfate reduction wetlands Wheal Jane |
|
| |
Abstract |
Passive (wetland) treatment of waters draining abandoned and derelict mine sites has a number of detrac-tions. Detailed knowledge of many of the fundamental processes that dictate the performance and longevity of constructed systems is currently very limited and therefore more research effort is needed before passive treatment becomes an “off-the-shelf” technology. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1569-1705 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Dec.; Pitfalls of passive mine water treatment; 2; FG als Datei vorhanden 4 Abb., 1 Tab.; VORHANDEN | AMD ISI | Wolkersdorfer |
Approved |
no |
|
| |
Call Number |
CBU @ c.wolke @ 10138 |
Serial |
336 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Tsukamoto, T.K.; Miller, G.C. |
|
| |
Title |
Methanol as a Carbon Source for Microbiological Treatment of Acid Mine Drainage |
Type |
Journal Article |
| |
Year |
1999 |
Publication |
Water Res. |
Abbreviated Journal |
|
|
| |
Volume |
33 |
Issue |
6 |
Pages |
1365-1370 |
|
| |
Keywords |
mine water treatment mining activity sulfate-reducing bacteria microbial activity acid mine drainage methanol passive treatment systems sulfate-reducing bacterium sp-nov |
|
| |
Abstract |
Sulfate reducing passive bioreactors are increasingly being used to remove metals and raise the pH of acidic waste streams from abandoned mines. These systems commonly use a variety of organic substrates (i.e. manure, wood chips) for sulfate reduction. The effectiveness of these systems decreases as easily accessible reducing equivalents are consumed in the substrate through microbial activity. Using column studies at room temperature (23-26 degrees C), we investigated the addition of lactate and methanol to a depleted manure substrate as a method to reactivate a bioreactor that had lost >95% of sulfate reduction activity. A preliminary experiment compared sulfate removal in gravity fed, flow through bioreactors in which similar masses of each substrate were added to the influent solution. Addition of 148 mg/l lactate resulted in a 69% reduction in sulfate concentration from 300 to 92 mg/l, while addition of 144 mg/l methanol resulted in an 88% reduction in sulfate concentration from 300 to 36 mg/l. Because methanol was found to be an effective sulfate reducing substrate, it was chosen for further experiments due to its inherent physical properties (cost, low freezing point and low viscosity liquid) that make it a superior substrate for remote, high elevation sites where freezing temperatures would hamper the use of aqueous solutions. In these column studies, water containing sulfate and ferrous iron was gravity-fed through the bioreactor columns, along with predetermined methanol concentrations containing reducing equivalents to remove 54% of the sulfate. Following an acclimation period for the columns, sulfate concentrations were reduced from of 900 mg/l in the influent to 454 mg/l in the effluent, that reflects a 93% efficiency of electrons from the donor to the terminal electron acceptor. Iron concentrations were reduced from 100 to 2 mg/l and the pH increased nearly 2 units. (C) 1999 Elsevier Science Ltd. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0043-1354 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Apr; Methanol as a Carbon Source for Microbiological Treatment of Acid Mine Drainage; Isi:000079485400004; file:///C:/Dokumente%20und%20Einstellungen/Stefan/Eigene%20Dateien/Artikel/10197.pdf; AMD ISI | Wolkersdorfer |
Approved |
no |
|
| |
Call Number |
CBU @ c.wolke @ 10197 |
Serial |
50 |
|
| Permanent link to this record |
