Abstract:Using corn fermentation broth as the carbon source for microbial sulfate reduction system can significantly reduce the cost of reduction, which is of great significance in realizing the economic and efficient treatment of sulfate wastewater. The effects of ratio of composite carbon source, ratio of carbon to sulfur (CODcr/SO42-, C/S) and pH value on the reduction of sulfate by sulfate reducing bacteria (SRB) were investigated. The results show that when the initial concentration of SO42- is (1 000±50) mg/L, the five composite carbon source ratios are able to obtain better sulfate reduction effect, and the residual concentration of SO42- is less than that of the groundwater quality standard Class Ⅳ water quality of 350 mg/L. When the initial C/S ratio is in the range of 0—3.5, with the increase of the C/S ratio, the sulfate reduction rate by SRB increases, but the remaining sulfate reduction utilization efficiency of carbon source decreases. The sulfate reducing activity of SRB is the best when the initial pH value is close to 7.0. The changes in pH value and ORP of the reaction system can accurately indicate changes in bacterial activity.