Advanced start up of UASB reactors by adding of water absorbing polymer

Abstract

We have developed a new approach to enhance granulation by adding water absorbing polymer (WAP) particles into the inoculated digested sludge. In this study, the effect of adding WAP on formation of anaerobic granular sludge was evaluated in lab-scale UASB reactors using two typical synthetic wastewater, i.e. glucose or volatile fatty acid (VFA) mixture solution. In addition, side by side with the lab-scale experiment, a pilot-scale experiment using the VFA mixture was carried out to evaluate the availability of accelerated start-up by adding WAP. The development of granular sludge was significantly enhanced by adding WAP. Granules developed on glucose and VFAs had high methanogenic activities and good settleability. From results of lab-scale experiment, the recommended dosage of WAP was about 750 mg/l of reactor volume. The results, pilot-scale experiment, indicated the availability of accelerated start-up by adding WAP.