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The occurrence, distribution and nature of ambient thiobacilli along with their ability to oxidize different sulphur species under simulated natural and in vitro culture conditions were studied in the polluted and unpolluted sites of the River Ganga.
Thiobacillus thioparus, T. thiooxidans and T. denitrificans were isolated from the river water. the former two occurred in both polluted and unpolluted sites, while T. denitrificans occurred in polluted areas only. the paper pulp mill effluent discharge area contained the highest population of T. thioparus. the sewage drainage area showed relatively higher populations of T. thiooxidans and T. denitrificans.
The present study revealed that only biological oxidation of either thiosulphate or elemental sulphur occurred in the river water. All the thiobacilli screened oxidized thiosulphate, and three-fourths of them oxidized elemental sulphur. Some strains were found to be very good acidifiers. in spite of such acidification by the ambient thiobacilli, the pH of the river water remained alkaline. the specific rates of thiosulphate (0.18 -0.51 μMmolh-1 mg-1 cell) and sulphur (1.3 - 6.2 Normality day-1 mg-1 biomass) oxidations under simulated natural condition were found to be higher in polluted areas when compared with the unpolluted one (sulphur: 0.8 - 1.0 Normality day-1 mg-1).
Further, addition of thiouslphate or elemental sulphur in the river water in simulated in vitro condition resulted in the increase of respective oxidation rates. the variations in the natae of pollutants discharged into the river water influenced the oxidation rate of thiosulphate or sulphur. 相似文献
Thiobacillus thioparus, T. thiooxidans and T. denitrificans were isolated from the river water. the former two occurred in both polluted and unpolluted sites, while T. denitrificans occurred in polluted areas only. the paper pulp mill effluent discharge area contained the highest population of T. thioparus. the sewage drainage area showed relatively higher populations of T. thiooxidans and T. denitrificans.
The present study revealed that only biological oxidation of either thiosulphate or elemental sulphur occurred in the river water. All the thiobacilli screened oxidized thiosulphate, and three-fourths of them oxidized elemental sulphur. Some strains were found to be very good acidifiers. in spite of such acidification by the ambient thiobacilli, the pH of the river water remained alkaline. the specific rates of thiosulphate (0.18 -0.51 μMmolh-1 mg-1 cell) and sulphur (1.3 - 6.2 Normality day-1 mg-1 biomass) oxidations under simulated natural condition were found to be higher in polluted areas when compared with the unpolluted one (sulphur: 0.8 - 1.0 Normality day-1 mg-1).
Further, addition of thiouslphate or elemental sulphur in the river water in simulated in vitro condition resulted in the increase of respective oxidation rates. the variations in the natae of pollutants discharged into the river water influenced the oxidation rate of thiosulphate or sulphur. 相似文献
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氧化亚铁硫杆菌 (Thiobacillusferrooxidans)是极端嗜酸性的专性自养细菌 ,广泛分布于硫化矿床、酸性矿水及土壤中 ,最适生长pH 2 .0~ 2 .5 .氧化亚铁硫杆菌很早就被广泛应用于有用金属的浸出 ,特别适合于从低品位的矿石中浸出和回收稀有贵重金属 .这种方法具有低成本、低能耗、无污染等特点 ,因而在能源日益紧缺的今天 ,受到人们越来越多的关注 .目前许多国家已经成功地利用细菌浸出液技术开采多种金属 ,如铜、铀、金、钴、镍、锌和铅等 .其主要作用原理是通过氧化FeSO4 或FeS2 产生Fe3 氧化剂 ,氧化… 相似文献
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Biological mine drainage treatment 总被引:1,自引:0,他引:1
Drainage from sulphur mines contains a high concentration of ferrous iron and it is strongly acidic. The mechanism of acid mine drainage formation was briefly explained. As a case study, successful measures taken at the abandoned Matsuo mine, Iwate Prefecture, Japan, for preventing the pollution in receiving rivers was presented in this paper. The measures consisted of the construction works against pollution sources and the construction of a drainage treatment plant in which Thiobacillus ferrooxidans oxidizes ferrous iron under a low pH condition, and produced ferric iron is removed by sedimentation. Then, a laboratory-scale fluidized bed reactor using anion exchange resin as attaching material for the bacteria was examined in order to improve the efficiency of biological oxidation of ferrous iron. More than 90% of oxidation had been maintained for 2 months at 1 h of HRT, which suggests that the size of the oxidation tank could be reduced. 相似文献
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微生物对煤系固体废弃物淋滤液污染性影响 总被引:1,自引:0,他引:1
煤矸石和粉煤灰是煤矿区的两种主要废弃物,它们不仅占用大量的土地,同时也对矿区环境产生了严重污染。分别接种氧化硫硫杆菌和解磷细菌于煤矸石和粉煤灰中,通过柱状淋滤试验研究微生物对两种固体废弃物淋滤液污染性的影响。结果表明:煤矸石中添加氧化硫硫杆菌能显著脱除煤矸石中的硫,同时淋滤液中也生成了大量的H+和铁离子,使淋滤液中硫酸根和磷酸根离子浓度显著增大,超出了GB3838-2002《地表水环境质量标准》的指标。粉煤灰中添加解磷菌能显著提高淋滤液中的磷含量和电导率,但对淋滤液的pH、SO42-和铁离子影响不明显。氧化硫硫杆菌和解磷细菌对煤矸石和粉煤灰混合工艺处理效果较好,粉煤灰在一定程度上降低了硫、磷和铁的污染性。 相似文献
47.
选用嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans,简称T.f)、氧化硫硫杆菌(Thiobacillus thiooxidans,简称T.t)作为实验菌种研究其对线路板(Printed circuit board)粉金属铜的浸出;试验以单一菌种、混合菌种、无菌培养基及酸性蒸馏水进行浸出实验研究,通过对比不同条件下的浸出效果,得出单一氧化亚铁硫杆菌(T.f)的浸出效果最好,浸出率达到92.1%。通过对浸出过程中pH、ORP及Fe2+、Fe3+变化分析,发现Fe3+的氧化作用在铜的浸出过程中起主导作用,酸浸也有一定的贡献;对浸出后残余的PCB进行XRD及SEM观察分析发现,PCB组成成分中含有大量的酚烃、苯酚及邻、对位取代酚以及少量的长链烷烃及其脂肪烃,此类有机物在浸出过程中均与细菌或其代谢物发生了作用。 相似文献
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通过利用复合硫杆菌(氧化亚铁硫杆菌和氧化硫硫杆菌)在不同接种量(5%,10%,20%)对市政污泥进行生物淋滤实验,探讨了淋滤过程中pH和氧化还原电位(ORP)、Mn的淋滤效果及淋滤过程中其形态的变化。结果表明:该方法能有效淋出污泥中的Mn,生物淋滤12d后,10%接种量反应器Mn的淋出率达到100%;Mn的淋出率受pH和ORP的双重影响,与pH和ORP的关系为:淋出率等于2.439-0.452pH-0.002ORP;各形态中Mn的可交换态和残渣态变化幅度大,从形态变化上表明该淋滤反应对Mn具有有效的淋出;Mn各形态的淋滤能力是:碳酸盐结合态>铁锰氧化物结合态>残渣态>有机物结合态。 相似文献
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