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The effectiveness and cost of the sulfate-reducing bacteria (Sulfate Reducing Bacteria SRB) for treatment of acid sulfate wastewater main factor is the carbon source. SRB carbon source material can be done up to now reported in the literature over 100 kinds; including lactate is the best, but it is expensive, low utilization rate of wastewater treatment effect; organic compounds in water too much, resulting in treated water can not national emission standards, so finding a source of adequate, easily obtained, low-cost material do SRB carbon source is the main purpose of this thesis. Soybean fermented and unfermented soy COD and nitrogen content of the difference between static test methods to explore the feasibility of with fully fermented soybeans as a carbon source, the main effects of SO42-removal rate changes over time, different carbon sources, different influent SO42-concentration of SO42-removal rate. Based on pre explore experimental results, to determine influent acidity COD/SO42-, SRB concentration, influent SO42-concentration affect the effectiveness of wastewater treatment as a carbon source, fully fermented soybeans, by measuring SO42-removal rate influent pH, water pH, COD removal rate of the effluent sulfide concentration, water redox potential, the effluent total sulfur concentration of the same amount to determine the most appropriate test conditions; then adding a growth factor D in the influent growth factor D and without growth factor D comparison test. The test results show that: the fully fermented soybeans as a carbon source, when the the influent acidity of 0.5-9.0, SO42-removal rates of up to 92.31%. SO42-removal efficiency, water pH, sulfide concentration maximum at COD/SO42- = 3.0, respectively, 93.73%, of 6.52,32.52 mg / L, therefore choose COD/SO42 of 3.0 for the most suitable experimental parameters. As the the SRB concentration increases, the removal rate of sulfate, COD removal and effluent sulfide concentration increases gradually, the effluent pH, redox potential and the total sulfur concentration in water decreases gradually, but when when the SRB concentration greater than 10%, they are substantially constant, considering the cost SO42-removal and carbon, and select a concentration of 10% of the SRB. Less than 2500mg / L when the influent concentration of SO42-, SO42-removal rate is higher than 86.2%. Join growth factor D reduces the influent pH S042-removal rate, the effluent pH, COD removal efficiency and effluent sulfide concentrations, SRB can also be better at low pH treatment of acid sulfate wastewater.
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