Abstract
The effect of adding water absorbing polymer (WAP) on formation of anaerobic granular sludge was evaluated in lab-scale UASB reactors using glucose or volatile fatty acid (VFA) mixture. The development of granular sludge was significantly enhanced by adding WAP. Granules developed on glucose and VFAs had high methanogemc activities and good settleability. The recommended dosage of WAP was between 750 and 1500mg/l of reactor volume. SEM observations suggested that rod-type Methanothrix-like organisms were prevalent species in the granules developed on the glucose while filamentous Methanothrix-like bacteria were predominant in the granules grown on the VFA mixture.
