Biological WWTP for Coke Battery Wastewater Discharge: Design, Construction and Start-Up Challenges and Solutions

摘要

DTE Energy Inc./EES Coke Battery LLC (DTE/ EES) operates the No. 5 coke battery and the No. 3 byproduct recovery plant located on Zug Island in Detroit, Mich. Site operations generate process wastewater at a rate of approximately 200 gpm. This wastewater is processed through the byproducts recovery plant on-site to remove primarily tar, phenols and free/fixed ammonia. These byproducts that are removed from the wastewater stream are recovered in various forms for additional processing, reuse, sale and/or disposal. The effluent wastewater stream passing through this process was discharged to the Detroit Water and Sewerage Department (DWSD) public-owned treatment works (POTW) via the municipal sanitary sewer system with no further treatment. In March 2005, the DWSD presented new discharge limitations in the City of Detroit Ordinance 08-05 (National Categorical Pretreatment Standards are incorporated by reference into this ordinance), which applied to many industrial users of the sewer system in the Detroit metropolitan area. Most notably for DTE/EES, this ordinance reduced the discharge limit for mercury to <0.2 μg/L and the limit for phenolic compounds to 0.5 mg/L.