Evaluation of Start-up Performance of Anaerobic Bioreactors with Unit Substrate Degradation Rate Constant

摘要

Performance of a designed integrated UASB reactor was tested by treating synthetic sucrose wastewater. The start-up of the reactor went through 6 stages in 55 days. The volume-loading rate (VLR) of influent was increased step by step from 2.09 kg COD·(m3·d)-1 to 28.02 kg COD·(m3·d)-1, and COD removal rate was up to 98.45% in the end. An evaluation method using K2 ', i.e. unit substrate degradation rate constant, was proposed to indicate the variance of performance of the reactor in the different stages during the start-up process. Test data obtained from each stage were analyzed and evaluated using K2 ' value, which indicated that an optimum performance reached at the 5th stage of the UASB reactor. The K2 ' values of some test data about the start-up of anaerobic reactors reported in other papers were also calculated and then the performances were compared and evaluated. It is obvious that the correlative operation parameters leading to a maximum K2' account as the parameters of optimal operation performance of anaerobic reactor. It is better and more comprehensive to employ K2' as evaluation criterion to evaluate operation performance of bioreactors than using removal efficiency or volume-loading rate solely.