Technical and Economic Implications of Low Effluent Concepts for Bleached Kraft Mills, 1994 Environmental Conference Proceedings

Heikki Mannisto, Eva Mannisto, Pertti Winter

Sponsored by 20 companies, including six North American pulp and paper companies, a study of technical and economic consequences of the conversion of a bleached kraft mill to low effluent concepts was carried out. Three mill cases were evaluated: a) an old mill; b) a more recent mill; and c) a greenfield mill. The study also included an evaluation of the environmental impacts as well as the assessment of the risks involved in implementing the low effluent concepts.

The study indicates that the low effluent concepts involving the recovery of bleach plant effluent are not cost effective for existing mills. Depending on the initial status of the mill and the concepts selected for implementation, the total cost, including variable cost, maintenance cost and capital charges, is estimated to increase the cost of pulp manufacture by US $50 – 150/Adt. Even for a greenfield mill designed for liquid effluent-free operation, the total increased cost of pulp manufacture is expected to be US $20 – 60/Adt, as compared to a conventional mill.