The fermentation type of acidogenic bacteria and their cooperation with SRB in an acidogenic sulfate-reducing reactor
产酸-硫酸盐还原系统中产酸菌的发酵类型及其与SRB的协同作用

The fermentation type of acidogenic bacteria (AB), the substrate utilization of sulfate-reducing bacteria (SRB) and the cooperation of these two kinds of bacteria in an acidogenic sulfate-reducing reactor were investigated via continuous-flow and batch tests. The results achieved from batch test showed that the AB performed ethanol type fermentation according to the proportion of ethanol and acetic acid in terminal liquid products, which were 35.6% and 37.7% respectively. It is found that SRB preferred to hydrogen, ethanol and lactic acid as substrate, but not the acetic acid, propionate acid and butyric acid. In the meantime, SRB could convert ethanol into acetic acid. Therefore, acetic acid accumulated in the terminal liquid products since it is hard to be transformed by SRB any more. The results got from continuous-flow experiment showed that the cooperation of AB and SRB has great effect on the sulfate-reducing efficiency. When they cooperated well, the sulfate removal rate was high; otherwise, the sulfate removal rate was low.