The Microbial Metabolic Characteristics in the Course of Sulfate-Reduction

Acid-producing phase reactor of two-phase anaerobic treatment process has remarkable advantages treating sulfate-laden wastewater. In order to investigate SRB population‘s capability of utilizing substrate and the microbial acidification type formed during the course of sulfate reduction, continuous-flow and batch tests were conducted in a continuous stirred tank bio-film reactor supplied with sodium sulfate as electron acceptor. The experimental results demonstrated that the acidification type formed b...

The Microbial Metabolic Characteristics in the Course of Sulfate-Reduction

Acid-producing phase reactor of two-phase anaerobic treatment process has remarkable advantages treating sulfate-laden wastewater. In order to investigate SRB population's capability of utilizing substrate and the microbial acidification type formed during the course of sulfate reduction, continuous-flow and batch tests were conducted in a continuous stirred tank bio-film reactor supplied with sodium sulfate as electron acceptor. The experimental results demonstrated that the acidification type formed by acidogenic bacteria (AB) population was ethanol-type fermentation, but an Acetic Acid Type Microbial Metabolism was formed by the whole community based on the proportion of acetic acid to terminal products. SRB population's capability of utilizing substrate showed an order of hydrogen> ethanol> lactic acid >propionate acid> butyric acid>acetic acid. Although volatile fatty acids utilized SRB (FSRB) easily converted ethanol and lactic acid into acetic acid, acetic acid-utilized SRB (ASRB) could hardly utilize acetic acid further, which resulted in acetic acid accumulation in terminal liquid products. Moreover, ASRB could not win the competition against FSRB. A criterion was presented to explain the formation of an Acetic Acid Type Microbial Metabolism.