Pilot Study of Biological - Ecological Filter (BEF) for Municipal Wastewater Treatment

摘要

Pilot-scale anaerobic hydrolysis - high load biological filter - earthworm filter combined process was set-up for the treatment of domestic wastewater. Results showed that CODcr and ammonia nitrogen of the effluent water after treated were 15-50 mg/L, and 1～ 3mg/L respectively, in the operating condition of residence time of pool acid hydrolysis (5h) and hydraulic loading of high-capacity biological filter (15m3/m2·d), and hydraulic loading of Microbe Earthworm Eco-Filter (7.0m3/m2·d), when the CODcr and ammonia nitrogen of the influent water were 280～450 mg/L and 2535 mg/L, respectively. Water quality of the effluent water could meet the first requirement of Chinese Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002). A large number of protozoa and metazoan were found in the microscopic examination of biofilm, implying operational stabilization of biofilter and large degradation of organic matter.