LABORATORY STUDIES ON ENHANCEMENT OF GRANULATION IN THE ANAEROBIC SEQUENCING BATCH REACTOR

The phenomenon of granulation was studied in anaerobic sequencing batc h reactors (ASBRs) treating a synthetic sucrose wastewater, The object ive was to study methods of minimizing the time typically required for start-up of high rate anaerobic processes, such as the ASBR, when uti lizing biomass from typical anaerobic digesters, More specifically, th e goal was to develop granular biomass soon after initial start-up of the ASBR in order to decrease the overall time required to achieve hig h rate anaerobic treatment, Laboratory-scale ASBRs were seeded with an aerobically digested municipal biosolids and operated until granulatio n was observed, Granule development was measured by determination of t he average particle diameter of a representative sample of biosolids f rom the ASBRs. Cationic polymer was added to the test ASBR to enhance rapid granule development and to aid in start-up. Cationic polymer add ition reduced the time required to form granules by approximately 75% compared to an un-enhanced control ASBR. (C) 1997 IAWQ. Published by E lsevier Science Ltd.