Ecological characteristics of predominant populations in an acidogenic sulf ate-reducing reactor

Preponderant populations of sulfate-reducing bacteria (SRB-ZH07) and acidogenic-bacteria (AB-ZH01) in an acidogenic sulfate-reducing reactor were isolated. The effects of pH value, COD/SO₄^2- and oxgen on the growth of AB-ZH01 and SRB-ZH07, and their substrates utilization were investigated. The results of the experiment showed that AB-ZH01 and SRB-ZH07 could grow well under pH 7.0, the sulfate removal rate was also the highest. AB-ZH01 could also grow well under pH7.0 and pH 6.0. Sulfate removal rate was as high as 94.24% when supplied lactic acid as the sole carbon source for SRB-ZH07. When supplied glucose as the sole carbon source for AB-ZH01, the increase of cell number could be the highest. SRB-ZH07 could live in aerobic and anaerobic condition, but growth rate higher in aerobic condition than that in anerobic condition. In addition, SRB-ZH07 could not reduce sulfate in aerobic conditions. When COD/SO₄ ratio was over 2.0, sulfate removal rate could reach about 80% supplying lactic acid as the sole carbon source. Otherwise, sulfate removal rate was less than 50%.