Anaerobic Treatment of Yeast Effluent in an Expanded Granular Sludge Bed Reactor

The purpose of this study was to investigate the use of an anaerobic expanded granular sludge bed (EGSB) reactor, to treat high strength yeast wastewater. The EGSB reactor was seeded with granular sludge from the UASB reactor of a full-scale brewery factory. Experiment was done under operational condition of a total superficial up flow velocity(Vup) of 6m·h-1, Temperature of 30□, COD concentration of about 20 g·L-1. Start-up of a step-wise manner was adopted. The volumetric organic loading (BV.TCOD) was increased progressively by varying flow of the influent, and extent of raising BV.TCOD should be less than 30% at each step. After the start-up period of 79 days, the BV.TCOD of the EGSB reactor reached 15.8 kg COD m-3·d-1, and obtained COD removal efficiency of 69.5%. The specific methanogenic activity of the sludge was about twice higher than that of the seeded sludge. The experimental results indicated that the anaerobic treatment of yeast effluent in an EGSB system appears to be a feasible option.