USE OF THE ADVANCED BIOLOGICAL NUTRIENT REMOVAL PROCESSES IN KOREAN MUNICIPAL WASTEWATER TREATMENT PLANTS WITH LOW BODs

The Municipal Wastewater Treatment Plants (WWTP) in Korea are required to provide phosphorous and nitrogen removal to meet by year 2001, a new effluent limit required by the Korean Environmental Protection Agency. In the US, the advanced biological nutrient removal (BNR) processes such as A2/O, VIP, and UCT are being popular for upgrading the activated sludge process in WWTPs, to meet stringent discharge limitations for nutrients. To assist in the planning and implementation of nutrient removal for design of a new WWTP serving a new industrial area in Korea, three enhanced BNR processes were pilot tested; (a) Main Stream (A2/O with Return Activated Sludge Denitrification), (b) Side Stream or modified PhoStrip, and (c) Sequencing Biological Reactor (SBR). The pilot testing was conducted in two stages. The major industrial sources contributing in over 90% of the discharge into the WWTP are from electric wire, semiconductor, and electronics facilities. The wastewater from the industries, weak in BOD and COD, would be pretreated prior to be discharged into the WWTP. This paper provides a summary of the First-Stage (1st-Stage) evaluations leading to identification of A2/O process that could meet the treatment requirements of the facility. Also, it provides conclusions derived from the 1st - and 2nd -Stage pilot investigations.