ABSTRACT

Sulphate (SO4) abundance in the earth’s crust contributes largely to industrial wastewater contamination lowering the pH, which exuberates the dissolution of metals forming acidic drainages. Biological sulphate reduction as a remediation process can be affected by factors such as pH, temperature and high sulphide concentrations. In this study, sulphate-reducing bacterial community enriched from mine wastewaters was applied in semi-automated bioreactors to assess the effects of these factors on microbial sulphate reduction capacities. Low pH (3.5) and temperature (10°C) were observed to promote the toxicity of sulphur-reduced species on the consortium while mesophilic temperature (25°C) and near neutral pH (6.2) were observed to induce optimum SO4 reduction attaining a maximum of 95% SO4 reduction. Obtained SO4 reduction dynamics data was then applied in formulating a unique non-competitive inhibition equation that models biogeochemical events during SO4 reduction under varied pH and temperature conditions and predicts the efficacy of a bioremediation system.

摘要

地壳中丰富的硫酸盐 (SO4) 在很大程度上导致了工业废水污染，降低了 pH 值，从而促进了金属的溶解，形成酸性废水。生物硫酸盐还原作为修复过程可能会受到 pH 值、温度和高硫化物浓度等因素的影响。在这项研究中，从矿山废水中富集的硫酸盐还原细菌群落被应用于半自动化生物反应器中，以评估这些因素对微生物硫酸盐还原能力的影响。观察到低 pH (3.5) 和温度 (10°C) 会促进硫还原物质对聚体的毒性，而观察到中温温度 (25°C) 和接近中性 pH (6.2) 会诱导最佳 SO4 还原，从而达到SO4 最多减少 95%。