Development of economical advanced biological treatment process for sewage containing dye wastewater

초록

Introduction of advanced treatment process into existing Sewage Treatment Plants(STP) for nutrient removal become necessary due to the strengthened effluent standards in Korea. A number of existing plants need to go through this process. The plant under investigation receives basically three waste streams : one wastewater is from residential area, the second is industrial wastewater from industrial complex, and the third is also industrial wastewater exclusively from the dyeing industrial complex. At present the plant has two parallel secondary biological treatment processes : one is only for the domestic sewage from the residential area (Qave=179,000 m3/d), the other is exclusively for industrial wastewater (Qave=206,000 m3/d) combining together with wastewaters (Qave=80,000 m3/d) from the dyeing complex. There have been operational difficulties on the industrial wastewater battery due mainly to a lack of carbon sources. This happens because of the fact that the discharge requirements imposed upon the wastewater plant in the dyeing complex are so severe that its effluent, which is influent to the downstream plant, does not contain enough carbon sources. Enough carbon is mandatory for BNR and a preliminary experiment discloses that amounts of carbon needed can easily be secured by manipulating the legal discharge limits for the dyeing industrial complex because dyeing wastewater has high enough original organic carbons.