HIGH RATE ANAEROBIC DIGESTION OF PRIMARY AND SECONDARY SLUDGE USING THE STATIC GRANULAR BED REACTOR (SGBR)

摘要

Anaerobic treatment of primary and secondary municipal sludge was studied with a laboratory-scale SGBR at organic loading rates (OLR) from 2.8 ± 0.9 to 5.5 ± 1.7 g COD/L·d and hydraulic retention times (HRT) from 48 to 24 h. The results of this research demonstrated the SGBR system's potential to be a practical and competitive alternative to conventional anaerobic digestion of wastewater sludges. The laboratory-scale SGBR produced a biogas with a higher methane content (76 ± 4%) than the conventional anaerobic digester analyzed (59 ± 2.8%). Effluent volatile fatty acid (VFA) concentrations remained below 30 mg/L as HAc, indicating the potential to reduce process instability from the buildup of intermediate by-products. The low VFA concentrations of the SGBR's effluent also reduces odors compared to the discharge from conventional anaerobic digesters. The SGBR produced an effluent with low concentrations of organic matter due to the high removal rates in the system (e.g., average total suspended solids (TSS) and chemical oxygen demand (COD) removal efficiencies remained above 90% at all OLR and HRT conditions).