Monitoring the restart-up of an upflow anaerobic sludge blanket (UASB) reactor for the treatment of a soybean processing wastewater

Restart-up of an upflow anaerobic sludge blanket (UASB) reactor for the treatment of soybean processing wastewater was investigated. During the restart-up period, both chemical oxygen demand (COD) degradation efficiency and gas production rate increased. The specific methanogenic activity of anaerobic sludge and the fluorescence score for coenzyme F 420 in the effluent increased from 0.31 to 0.81 g-CH 4-COD/gVSS/d and from 153 to 313, respectively. Among the various operating parameters the volatile fatty acids (VFA) and the CH 4 content were the first to become stable, which could be used as the main parameter for the reactor restart-up. The coenzyme F 420 also existed in the effluent and its concentration had a similar changing trend to the specific methanogenic activity value of the anaerobic sludge. Therefore, the F 420 fluorescence score in the effluent could be used to determine the methanogenic activity of anaerobic reactors.