Scientist To Change Focus Of Research On Dioxin
(November 16, 1994, Washington, D.C.) - The focus of research on the environmental effects of pulp and paper mills will likely shift from chlorine to naturally occurring compounds in wood, scientists concluded last week at the 2nd International Environmental Fate and Effects of Bleached Pulp Mill Effluents conference in Vancouver, British Columbia.
Chlorinated compounds, such as dioxin, which are linked to chlorine use in pulp manufacture, were once a cause of environmental concern. "By switching to chlorine dioxide as the principal bleaching agent, we have reduced the environmental effects of chlorinated compounds to the point of insignificance," said Dr. Keith Solomon, Director, Centre for Toxicology, University of Guelph, Ontario. "With chlorine dioxide, we've peeled back the onion's layer we call dioxin, revealing effects which may be caused by natural compounds in mill waste water."
Moreover, research results presented at the conference may help mills decide between today's competing bleaching technologies: ECF, or Elemental Chlorine-Free, based on chlorine dioxide and TCF, or Totally Chlorine-Free, said conference Co-Chair Dr. John Carey, National Water Research Institute, Ontario.
"The studies haven't shown a major difference between ECF and TCF processes with respect to their environmental impacts," Carey said. "This may allow mills to choose a bleaching process based on market demand for the respective pulps, rather than a perceived difference in environmental performance."
Demand for ECF pulp is far outpacing that for TCF. Worldwide ECF pulp production now totals about 23.5 million tons, seven times that for TCF pulp, reported Canadian Papermaker in its October 1994 issue. In the US, ECF pulp production has grown by 1,300 percent since 1990 to capture 23 percent of the market. In comparison, TCF pulp production will barely reach one percent of the American market by year's end.
"This conference closes a chapter on dioxin. Chlorine dioxide has been key to the dramatic improvements measured in ecosystems downstream of US bleached pulp mills," said Doug Pryke, Executive Director of the Alliance for Environmental Technology (AET). "Already, mills based on chlorine dioxide bleaching are discovering ways to eliminate mill waste water."
AET is an international association of 18 forest products manufacturers and chemical companies dedicated to improving the environmental performance of the pulp and paper industry.