JOINT TREATMENT OF MUNICIPAL SEWAGE AND PULP MILL EFFLUENTS by The Green Bay Metropolitan Sewerage District Green Bay, Wisconsin 54305 a report for the Program #12130 EDX Engin Mary TD 899 P3 G78 EPA Review Notice This report has been reviewed by the Environmental use. For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price $6 Stock Number 5501-0206 This research project determined the technical and economic feasibility of jointly treating the influent to the present treatment facilities of the Green Bay Metropolitan Sewerage District in combination with the weak effluents from the pulping sections of four local paper mills, specifically American Can Company, Charmin Paper Products Company, Fort Howard Paper Company and Green Bay Packaging, Inc. Four activated sludge processes (conventional, step aeration, contact stabilization, and Kraus) were studied in parallel using 1-gpm pilot plants. At the end of the 12 months, the conventional and step aeration processes were eliminated from further consideration. The contact stabilization and Kraus processes were studied for an additional four and one-half months. Contact stabilization was selected as the most promising process and units were operated for an additional five months to obtain refined design and operating parameters for a full-scale treatment plant. Shortly after initial start-up, the pilot plants became infested with filamentous organisms identified as a bacterial species of the genus Thiothrix, a sulfur-storing organism. Of various procedures implemented, chlorina tion of the return activated sludge successfully controlled the growth of filamentous organisms which caused sludge bulking. It was also necessary to add nutrients to achieve the desired BOD: N: P ratios. The operation of the pilot plant units during the last study phase gave the following results: Extensive solids -handling unit process studies were conducted at the pilot plant site and in the cooperating manufacturer's laboratories. The capital costs to the individual participants, based on becoming a part of the joint venture or providing separate facilities, are presented. American Can Company and Charmin Paper Products Company are joining with the Green Bay Metropolitan Sewerage District in a joint treatment plant program. Fort Howard Paper Company and Green Bay Packaging, Inc. have elected to provide their own facilities. This report was submitted in fulfillment of Grant No. WPRD-60-01-67 between the Federal Water Quality Administration and the Green Bay Metropolitan Sewerage District. Key Words: Joint Treatment - Weak Pulp Mill Effluent - Municipal |