Integrated OAAO-ceramic membrane MBR process for the capacity expansion of municipal wastewater treatment plant

An integrated oxic-anoxic-anaerobic-oxic(OAAO)-ceramic membrane MBR process with a treatment capacity of 20 000 m3/d was built to solve the problem of long-term full-load and even overload operation of a municipal wastewater treatment plant in Dinghu, Guangdong Province, China. With microbial environment precisely control, high-efficiency treatment with micro-oxygenated organisms was realized. The project operated stably after completion, with COD and NH4+-N in effluent reaching the Ⅳ class water standard in the Environmental Quality Standard for Surface Water(GB 3838-2002), while TN and TP could also meet the Class A standard in the Pollutant Discharge Standard for Urban Wastewater Treatment Plants(GB 18918-2002) stably. This project involved a total investment of 40.61 million yuan, covered an area of 4 713.4 m2, and the unit treatment cost was 0.42 yuan/t. Compared with the AAO-denitrification filter process with the same treatment capacity in this wastewater treatment plant, integrated OAAO-ceramic membrane MBR process saved 43.8% of the total investment, reduced 66% of area and 19.23% of unit treatment cost, also decreased the waste sludge production to 1.5 t/d.