一株脱硫自养菌的鉴定和脱硫特性研究

Identification and Sulfide Removal Characteristics of a Desulfurizing Strain

从无锡市某硫酸厂采集的土样中分离到一株具有脱硫性能的自养菌,对该细菌的16S rDNA序列进行了测定,并根据16S rDNA构建了系统发育树,结合菌落、细菌形态鉴定菌株为那不勒斯硫杆菌(Thiobacillus neapolitanus),命名为TL-1。同时,考察了TL-1菌株在不同温度和pH条件下的脱硫效率,并在反应器中以氧化还原电位(ORP)为控制条件,对菌株的脱硫效果和生成的单质硫颗粒特性进行了研究,结果表明,摇瓶实验中,30°C、pH7.5为脱硫最佳条件。反应器运行时,ORP控制在?370mV条件下运行效果最佳,系统能够维持95%以上的硫化物去除率和85%以上的单质硫回收率,随着ORP的增大,生成的单质硫颗粒粒径有逐渐增大的趋势。

A desulfurizing chemoautotroph strain TL-1 was isolated and further identified in this study. Moreover a phylogenetic tree was constructed by comparing with the published 16S rDNA sequences of the relative bacteria species. Based on the colony and cell morphology, this strain was identified to be the strain of Thiobacillus neapolitanus. The effect of different temperature and pH on the strain was studied in shake flask. In the airlift reactor, the desulfurizing efficiency and the characteristics of the sulfur particles were investigated using Oxidation Reduction Potential （ORP） as the control factor. The results indicated that the optimal condition for desulfurizing in shake flask was 30℃ and initial pH of 7.5. In the airlift reactor, the optimal ORP was at -370 mv, under this condition, sulfide removal rate was over 95% and over 85% sulfide was transferred into sulfur. Moreover the sulfur particles size was enlarged with the increase of ORP.