A low footprint and excess sludge production system for wastewater treatment

This paper reports the results of a study aimed at evaluating the effectiveness of an innovative technology (SBBGR - Sequencing Batch Biofilter Granular Reactor) for treating environmentally relevant wastewater (i.e., municipal wastewater, textile industry effluents and sanitary landfill leachates). SBBGR is a periodic biofilter based on aerobic granular sludge featured by a low excess sludge production. The results have shown that for the selected wastewater SBBGR is able to remove, in a single stage, completely the biodegradable organic material and 80-90% of nitrogen and total suspended solids content even at an organic loading rate of 2.5 kg COD/m3.d. SBBGR operated at very high sludge age value (i.e., 150 to 800 d) and biomass concentration (i.e., 30-50 kgTSS/m3). Excess sludge production ranged from 0.05 to 0.1 kg of dry sludge per kg of COD removed.