Treatment of Adsorbable Organic Halide (AOX) from pulp and paper industry wastewater using aerobic granules in pilot scale SBR

Aerobic granulation of activated sludge was achieved in a pilot scale column type sequencing batch reactor (SBR) employed for the treatment of pulp and paper industry wastewater containing Adsorbable Organic Halide (AOX) in the range of 15-20 mg/L. Throughout the 780 days of operation the biomass trends to remain in between 7 and 8 g/L MLVSS and SVI reduced to 60-80 mL/g MLSS. After applying different selection pressure the average size of aerobic granule in the SBR was in the range of 2-4 mm. After achieving steady state conditions in the pilot plant, at an organic loading rateof 4.5 kg COD m(-3) day(-1) at 6 h HRT the degradation of AOX was significant and the effluent AOX concentration of below 5 mg/L was achieved. The results achieved in the study exhibit the viability of formation of aerobic granules in pilot scale SBR and maintenance of long-term strength of aerobic granular sludge with a high reduction of AOX in pulp and paper industry wastewater.