Five Great Reasons Why We Care: The Pulp and Paper Industry's Virtual Elimination Strategy

Section 2

PROVEN PROGRESS

 

The pulp and paper industry's virtual elimination strategy for persistent, bio-accumulative, toxic compounds included elimination of contaminated wood chips, use of precursor-free defoamers, and increased substitution of chlorine dioxide for chlorine. As a result, the industry has virtually eliminated the discharge of 2,3,7,8-TCDD/F from bleached chemical pulp and paper mills to the Great Lakes. Dr. Donald Mackay, former member of both the IJC Great Lakes Science Advisory Board and the VETF, noted that this approach is "an enlightened industrial response to an environmental concern" [12].

In Canada, bleached chemical pulp producers in the Great Lakes Region have achieved compliance with the Canadian Environmental Protection Act requirement that prohibits release of "final effluent which contains any measurable concentrations of 2,3,7,8-TCDD or 2,3,7,8-TCDF" [4]. In the US, final mill effluent from bleached chemical pulp producers in the Great Lakes Region shows no detectable concentrations of 2,3,7,8-TCDD; all but one have no detectable concentrations of 2,3,7,8-TCDF in final mill effluent [13].

The success of this effort sets a new level of performance. Estimates show that other sources are responsible for 99% of the total airborne and waterborne loadings of 2,3,7,8-TCDD/F to the Great Lakes [14].

VIRTUAL ELIMINATION OF 2,3,7,8-TCDD/F FROM THE BLEACHED CHEMICAL PULP AND PAPER INDUSTRY

The industry began implementation of the virtual elimination strategy in 1987 following confirmation that it was a source of 2,3,7,8-TCDD/F. As discussed earlier, the industry adopted three aspects of pollution prevention: product reformulation, raw material substitution, and changes to production processes. The process of increasing substitution of chlorine dioxide for chlorine, and in many cases complete replacement with chlorine dioxide, known as ECF, combines both raw material substitution and significant change to the production process.

Virtual elimination of dioxins and furans has not been limited to a few select locations; on the contrary, the industry has employed these pollution prevention technologies throughout North America. The Great Lakes, shared by both Canada and the US, and home to more than 20% of the world's fresh surface water, provide a model of pollution prevention success for other industries to follow.

Bleached Chemical Pulp Mills In the Great Lakes Region

The ten bleached chemical pulp mills in the Great Lakes Region have implemented stringent programs of pollution prevention, including precursor-free defoamers, elimination of contaminated wood supplies, and increased chlorine dioxide substitution. As shown in Figure 2.1, the weighted average chlorine dioxide substitution at these mills increased from 25% in 1988 to 70% by 1994.

On the basis of performance levels like these, it is projected that industry in the Great Lakes Region may voluntarily convert the entire production to complete substitution by the year 2000, reflecting market demand for ECF pulp and paper products, and response to regulations such as the Ontario MISA Pulp and Paper Effluent Regulations and the proposed US EPA Cluster Rule guidelines for the bleached chemical pulp and paper industry [15, 11].

 

FIGURE 2.1

Great Lakes Region Bleached Chemical Pulp Mills
Weighted Average Chlorine Dioxide Substitution

The application of the virtual elimination strategy produced dramatic results: 2,3,7,8-TCDD/F discharges have decreased more than 98% across the entire Great Lakes Region, as shown in Figure 2.2 .

 

FIGURE 2.2

Great Lakes Region Bleached Chemical Pulp Mills
Virtual Elimination of 2,3,7,8-TCDD/F to Waterways

Recently, the Center for the Biology of Natural Systems estimated the total US and Canadian 2,3,7,8-TCDD/F loadings to the Great Lakes from both airborne and waterborne sources. The report shows that the pulp and paper industry is now a negligible source to the Great Lakes [14]. The study estimates that 99% of 2,3,7,8-TCDD/F loadings are from other sources, as shown in Figure 2.3. This analysis confirms earlier estimates of the pulp and paper industry's contribution to environmental protection [16].

 

FIGURE 2.3

Estimated Loadings of 2,3,7,8-TCDD/F to the Great Lakes
Total Airborne and Waterborne Sources: 61.6 grams/year

Bleached Chemical Pulp Mills in the Canada and the United States

The remarkable success of the virtual elimination strategy occurred in all bleached pulp and paper regions throughout Canada and the USas shown in Figure 2.4 [17,18,19]. It should be noted that the US production is approximately three times that of Canada. The North American pulp and paper industry decreased discharges by more than 96% over the period 1988-1994.

 

FIGURE 2.4

Canadian and US Bleached Chemical Pulp Mills
Virtual Elimination of 2,3,7,8-TCDD/F from Waterways

ELIMINATION OF PRIORITY POLLUTANTS

The US EPA's proposed Cluster Rule for the pulp and paper industry includes limits for polychlorinated phenolic compounds [11]. The formation of polychlorinated phenolic compounds, as in the case of dioxins, decreases as chlorine dioxide substitution increases. As shown in Figure 2.5, as chlorine dioxide completely replaces chlorine in chemical pulp bleaching, such compounds are virtually eliminated [20].

 

FIGURE 2.5

Virtual Elimination of Polychlorinated Phenolics vs.
Chlorine Dioxide Substitution in Bleach Plant Effluent
Adapted from Solomon et. al., 1993 [21]

If formed during bleaching, polychlorinated phenolic compounds are also degraded in biological secondary treatment. Typically, the removal efficiency is 80% [22]. The application of the virtual elimination strategy combined with secondary biological treatment produced dramatic reductions in polychlorinated phenolic compounds as shown in Figure 2.6. The discharge of such compounds is projected to be virtually eliminated when the entire production in the Great Lakes Region moves toward complete replacement with chlorine dioxide, ECF.

 

FIGURE 2.6

Great Lakes Region Bleached Chemical Pulp Mills
Elimination of Polychlorinated Phenolics to Waterways

Potlatch Corporation, Cloquet, Minnesota

Experience at Potlatch's bleached chemical pulp and paper mill in Cloquet, MN, provides a specific example of the elimination of 2,3,7,8-TCDD/F by chlorine dioxide substitution. Potlatch Corp. increased chlorine dioxide substitution from 10% in 1989 to 100% in 1994. As Figure 2.7 shows, as chlorine was successively replaced with chlorine dioxide, 2,3,7,8-TCDD/F concentrations declined, reaching non-detect at 55% substitution [23]. Figure 2.8 shows the annual loadings by year from the same site.

 

FIGURE 2.7

Final Mill Effluent 2,3,7,8-TCDD/F
vs. Chlorine Dioxide Substitution
Potlatch Corp., Cloquet, Minnesota

FIGURE 2.8

Final Mill Effluent 2,3,7,8-TCDD/F
Potlatch Corp., Cloquet, Minnesota