Effluent Reduction Through Process Optimization -- A Case Study, 1995 Environmental Conference Proceedings

Daniel Parker

Parker, Messana & Assoc.

Mike Anderson

Boise Cascade Corporation

Frederick Weber

Boise Cascade Corporation

Robert M. Seamons

CH2M HILL

The Boise Cascade, Vancouver Paper Mill is facing increasingly strict effluent discharge requirements, both from local regulation and proposed EPA limits. The mill is also planning to increase secondary fiber production which will increase effluent pollutant loading. The cost of upgrading the existing effluent treatment system to meet the proposed limits was found to be prohibitive. Lower cost alternatives for meeting the discharge requirements were investigated, combining modifications to the existing treatment system with reduction of effluent within the process. A complete survey and characterization of the plant process effluent were conducted, and a series of projects developed to reduce effluent flow and solids. A solids and water balance was developed for the plant and used to verify the expected results of the proposed effluent reduction projects under various production scenarios. This showed that the plant effluent flow could be reduced by nearly 50% through a series of projects to recover and recycle filtrate and seal waters. The process effluent reductions, in conjunction with upgrades to the existing effluent treatment system, enabled the proposed limits to be met at a considerably lower cost. The process effluent reduction projects had the additional benefit of showing a return in reduced operating costs, and increased fiber recovery.