Toxicity Reduction and Organic Removal of Sulfite Pulp Effluents by Combined Aerobic Biofilter-Aerated Stabilization Basin System, 1995 Environmental Conference Proceedings

Alexandra Kantardjieff

EKOKAN Inc.

J. Peter Jones

Université de Sherbrooke

Marcel Caron

Stone-Consolidated

Richard Tellier

Stone-Consolidated

A pilot-scale treatability study was performed to evaluate the capability of a combined aerobic biofilter-aerated stabilization basin (ASB) system to effectively treat a sulfite pulp and paper mill effluent. Attention was focused on the ability of such system to reduce the conventional pollutants (BOD5 , SS and COD) and the toxicity as measured by rainbow trout, Daphnia magna and photoluminescent bacteria below the new Canadian regulatory levels. The study involved first the operation of a laboratory scale aerated biofilter reactor followed by six month testing of an industrial scale pilot plant of the combined system. The aerobic biofilter was used as a pretreatment on the sulfite mill wastewaters, followed by a polishing treatment in an ASB of this effluent and all other mill wastewaters. Monitoring was carried out to determine effluent discharge quality, critical operational parameters and full scale system design criteria. The results of this study support the initial expectations for effective treatment of sulfite mill effluents by a combined aerobic biofilter + aerated stabilization basin system. The results show conventional pollutants reduced below the new pulp and paper regulatory requirements and final effluent nontoxic to rainbow trout, Daphnia magna and photoluminescent bacteria.