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Showing 1 to 20 of 37 for “"sulphate reduction"”.
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A kinetic study on anaerobic sulphate reduction : effects of sulphate and temperature
… kinetic information on the effects of feed sulphate concentration and temperature on the anaerobic sulphate reduction process and to develop a kinetic model to explain this dependency. These objectives were addressed by performing batch and continuous sulphate reduction experiments using a …
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An integrated geochemical and microbiological investigation of sulphate reduction in hypersaline pans
… were used to derive a holistic picture of sulphate reduction in five hypersaline pans in South Africa. Sulphate reduction rates were determined using a radioactive tracer (35 So/-) technique. This was applied to determination of in situ sulphate reduction rates, the effect of increased …
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Metals recovery from industrial wastewaters and metallic hydroxide sludges through microbial sulphate-reduction.
… metals can be recovered via microbial sulphate-reduction as metallic sulphides suitable as basemetal smelter feed. The bacterium Desulfovibrio desulfuricans is capable of reducing sulphate sulphur to sulphide sulphur while simultaneously oxidizing organic carbon to carbon dioxide. The …
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The development of a kinetic model for biological sulphate reduction with primary sewage sludge as substrate
Central to this process is biological sulphate reduction (BSR) using primary sewage sludge (PSS) as the electron donor and organic carbon source, with the concomitant reduction of sulphate to sulphide and production of carbonate alkalinity. To optimise the design, operation and control of BSR with …
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Optimisation of a linear flow channel reactor for semi-passive, simultaneous biological sulphate reduction and partial sulphide oxidation
… activities and typically has high levels of sulphate and heavy metals, at acidic pH. Similarly, high sulphate neutral rock drainage is of increasing concern. High sulphate content increases water salinity leading to adverse effects on human health as well as agriculture. Types of ARD and …
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Entwicklung einer Technologie zur langzeitstabilen Biologischen Reinigung schwermetallbelasteter Bergbauwässer
… both high concentrations of heavy metals and sulphate was developed. The technology is based on the technical coupling of microbially mediated hydrolysis, fermentation and microbial sulphate reduction in a self-stabilising process. Electron donor for sulphate reduction is supplied by …
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An investigation into the relationship between process kinetics and microbial community dynamics in a lactate-fed sulphidogenic CSTR as a function of residence time and sulphate loading
The treatment of acid mine drainage and other sulphate-laden wastewaters usingbiological sulphate reduction technology has been shown to offer several advantages.This process effectively removes the following toxicants: sulphate, heavy metals andacidity. Previous studies have also revealed that the …
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A mathematical model of a high sulphate wastewater, anaerobic treatment system
High sulphate wastewaters, originating from industrial activity or from the biological oxidation of sulphide ores (acid mine drainage), cannot be discharged into the environment untreated. Apart from the high sulphate levels, these waters may be very acidic and have high dissolved heavy metal …
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A novel semi-passive process for sulphate removal and elemental sulphur recovery centred on a hybrid linear flow channel reactor
… These semi-passive systems typically target sulphate salinity through biological sulphate reduction catalysed by sulphate reducing bacteria (SRB). These anaerobic bacteria reduce sulphate, in the presence of a suitable electron donor, to sulphide and bicarbonate. However, the hydrogen …
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ORGANIC MATTER IN ANOXIC PORE WATER FROM GREAT BAY, NEW HAMPSHIRE
… and phosphate in Great Bay pore waters, rates of sulphate reduction and ammonia and phosphate production were calculated using a kinetic model (Berner, 1980). Calculated values of sulphate reduction at two sites in Great Bay agreed quite well with measured rates (Hines, 1981).</p><p>Dissolved …
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Linking microbial community dynamics and performance of a biological sulphate reducing system using a mixed volatile fatty acid stream as electron donor
… by lowering its pH and increasing its metal and sulphate loading, thus making it unsuitable for use by many forms of life. AMD must therefore be treated before entering nearby water systems and soils. An effective treatment technology is considered as the one that can result in water …
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Groundwater redox conditions at a petroleum contaminated site, Kuils River, South Africa : pathways for BTEX biodegradation
… constituents show that bioremediation via NO₃- reduction, Fe³+ reduction, and SO₄²- reduction (and possibly methanogenesis in the most reduced part of the plume) is occurring. In some cases redox processes are taking place simultaneously resulting in redox zones that overlap. Iron and sulphate …
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The effects of fish waste and oxytetracycline on the microbenthos
… day, with a shift away from microbially mediated sulphate reduction to methanogenesis in the degradation of fish waste. Most of the OTC was quickly washed out of the fish waste when added to the sediments, with small quantities of theantibiotic persisting throughout the duration of the study. …
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The formation and origin of carbonate minerals in the Darling and Yzerfontein hypersaline pans, Western Cape, South Africa
… organic-matter rich layer in which bacterial sulphate reduction is occurring (hydrogen-sulphide smell). All of the pans contain disseminated calcite, with only the Zwartwater North and Zwartwater South pans containing a mixture of dolomite and calcite. Yzerfontein and Zwartwater North pans …
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Element cycling in organic rich sediments on the Pakistan margin
… Mn supply to the OMZ sediments was limited by Mn reduction within the OMZ water-column. In turn, Mn was effectively transported out of the OMZ and accumulated in underlying oxic sediments. In contrast, Fe supply to the sediments appeared to be unaffected by the OMZ; however, benthic porewater Fe …
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An investigation towards passive treatment solutions for the oxidation of sulphide and subsequent removal of sulphur from acid mine water
… which was developed for the treatment of sulphate-laden mine water discharges. The system consists of modular sulphate reduction and sulphide oxidation units. A demonstration-scale plant was constructed at BHP Billiton’s Middelburg Colliery, however the sulphide oxidation unit, the linear …
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Terminal anerobic interactions in a microbial association isolated from landfill
… dioxide, although this has only been reported in sulphate-reducing bacteria (Widdel, Kohring & Mayer, 1983); and (ii) that a syntrophic association was involved in which the hydrogen produced, during hexanoate catabolism to acetate, was removed by a hydrogen-oxidising species such as a methanogen …
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The mechanism of cathodic depolarization exhibited by sulphate-reducing bacteria during metallic corrosion processes
The mechanism of the corrosive action of sulphate reducing bacteria of the genus Desulfovibrio towards ferrous metals has been investigated. This corrosive action is anomalous when considered in the light of established knowledge of corrosion processes, since it occurs in the absence of oxygen, at …
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