As the environmental significance of chlorinated waste streams from pulp mills has become more widely recognized, pressures to find substitutes for chlorine in the bleaching process have been applied to both the pulp and paper industry and the government agencies responsible for regulating the industry. To reduce the adverse effects of chlorinated effluents, a number of non-chlorine bleaching or "totally chlorine free" (TCF) technologies have been developed. Several of these processes are now in commercial use and generally accepted as proven technologies. To determine the environmental consequences of replacing chlorine with other bleaching agents, the non-chlorine bleaching alternatives have to be systematically investigated. The BC Ministry of Environment, Lands and Parks has retained Klohn-Crippen, in collaboration with H.A. Simons Ltd. to provide a technical review of the chemical and toxicological properties and environmental impacts of effluents and other wastes produced from kraft pulp mills using TCF processes in bleaching wood pulp to achieve the required brightening. By identifying the nature of waste streams from TCF processes and their effects on the environment, the environmental significance of non-chlorine bleaching processes can be appreciated prior to large scale commercial use. In addition, some findings may have applications in the determination of appropriate limits on overall discharges from non-chlorinated bleaching processes.
Klohn-Crippen Consultants Ltd.. 1994. Non-Chlorine Bleaching Pulp Mills: Chemical and Toxological Properties and Impacts of Effluents and Other Wastes. BC Ministry of Environment, Lands and Parks