Progressive system closure: A Canadian perspective

Abstract

Paper buying standards, environmental regulations, and economic factors are continuing the interest in progressing toward low effluent, closed-cycle pulp and paper mills. Customer satisfaction, reduced resource utilization, freedom to site mills in areas without a ready source of water and protection from future costs to meet tightening effluent regulations are some of the specific advantages associated with closed-cycle operation. Progressive system closure is gaining support in Canada as a way to achieve further effluent reduction, and to minimize the costs of environmental protection. This paper will provide a brief review of past and present mill efforts to apply system closure in Canadian pulp and paper mills. It will then describe some highlights from Paprican's program in progressive system closure which incorporates research and development activities in the areas of: water use reduction, improved prediction and design tools, dynamics and control, corrosion control, chemical separation and regeneration, removal and/or control of wood extractives, chemical additives, energy cost reduction and control of solid and gaseous emissions.