Our air emissions have been steadily declining. Air emissions from our facilities come primarily from two sources:
Boiler replacements and upgrades at our cellulose fiber mills have had a positive effect on air quality. Between 2000 and 2010, our cellulose fibers facilities reduced their SO2 emissions by 55 percent and their particulate matter emissions by 49 percent. In our wood products mills, we’ve reduced air emissions of volatile organic compounds by 33 percent since 2000. These trends are the result of process modifications and the use of lower-emitting additives as well as pollution-control equipment that has captured or destroyed a significant amount of emissions.
Our strategy for reducing air emissions evaluates cost effective options including process changes, efficiency improvements, and, when necessary, add-on pollution control equipment. Our approach is to determine the most effective means to meet regulatory requirements and improve performance while minimizing greenhouse gas and conventional air pollutant emissions.
Minute amounts of dioxin are released through permitted air emissions, such as from biomass-fired boilers, which burn wood residuals such as bark. Just as campfires release dioxin, so do our mills when we burn biomass fuel. We're addressing the environmental impact through techniques that improve combustion efficiency and temperature controls.
Sustainability in Action
Triple win at NORPAC
Our Longview, Wash., NORPAC joint venture, which produces newsprint and premium uncoated paper grades for publishers, has pulled off something even better than a win-win. In working to lessen the facility’s manufacturing footprint, the mill has achieved a triple win.
First, energy conservation: By capturing 90 percent more reusable steam heat and recycling (as low pressure steam or hot water) elsewhere in the manufacturing process, the mill has reduced its demand for fresh steam.
Second, manufacturing cost savings: By recycling heat, the facility has reduced the amount of purchased steam per ton of production by about 15 percent. This has resulted in cost savings for the mill, even as pulp production increased by about 25 percent.
Third, environmental improvements: Projects to conserve energy and increase fiber recovery have reduced air emissions of volatile organic compounds and carbon monoxide by about two thirds (compared to 2005 levels and despite increased production). These reductions have multiple air-quality benefits for the environment and human health, since some volatile organic compounds can undergo transformations that may contribute to downwind visibility impairment or ozone formation.
