Turbidity and BOD Control at Schoeller Technical Papers, Inc., 1992 Environmental Conference Proceedings

In spite of a rigorous spill control system, Schoeller Technical Papers in Pulaski, New York, was faced with a quantitative turbidity limit of 75 NTUs and even tighter BOD and TSS limits in 1992. A comprehensive approach was employed at Schoeller Technical Papers to first identify wasteload including BOD, COD, turbidity, and TSS. After a thorough in-mill sewer sampling program, an in-mill spill control system and two 30,000-gallon equalization tanks were designed to control turbidity violations. In addition, variable speed mixers were installed in the primary clarifier to facilitate proper floc formation, thereby lowering primary effluent turbidity and TSS.

To meet upcoming BOD and TSS limits, a pilot test program was designed to test 60-degree crossflow and vertical media installed in two separate biotower treatment plants. Schoeller Technical Paper’s only other plant producing the same technical grade paper is in Germany, where wastewater is treated in a biotower containing vertical media plastic strips. The loading at Schoeller’s mill in Pulaski varies between 15 and 50 ppd/1000 CF. Results of the pilot test program indicated removals of greater than 75 percent BOD with both types of media; however, the 60-degree crossflow media could be installed at a significant cost savings to Schoeller. Therefore, a secondary treatment system was designed and installed including a neutralization system to adjust pH, a 70-foot-diameter bio-tower, a secondary pump station, and associated instrumentation and controls.