REMOVAL OF COD AND NITROGEN IN WASTE-WATER USING SEQUENCING BATCH REACTOR WITH FIBROUS PACKING

An 11-litre sequencing batch reactor (SBR) filled with fibrous packing was found to be very effective for the removal of not only Chemical Oxygen Demand (COD), but also nitrogen from synthetic wastewaters with 250-1034 mg/l of COD and 22-114 mg/l of nitrogen. As compared to the conventional SBR, this system had a shorter cycle time by skipping the settling step. In addition, denitrification was efficiently conducted in the interior of the 'bio-pompons', which were formed by the attached growth of biomass on the fibrous packings, even though the bulk of the reactor was under constant aeration. The system was tested at 12 loading conditions, ranging from 0.56 to 4.51 kg-COD/m3-day and from 0.04 to 0.49 kg-NH3-N/m3-day. On average, 95% of COD was removed within 2 h of aeration, while 57% of total nitrogen was removed after a retention time of 4-8 h.