Air Quality
Our air emissions have been steadily declining. Air emissions from our facilities come primarily from two sources:
- Industrial boilers that burn fuel to produce electricity and steam and recover chemicals used in the pulping process
- Airborne chemicals released in the production of wood, pulp and paper products
Air Quality Measures
Boiler replacements and upgrades at pulp and paper mills have a positive effect
on air quality. Between 2000 and 2009, our cellulose fibers facilities reduced their
SO2 emissions by 25 percent and their particulate matter emissions by
36 percent. In our wood products mills, we’ve reduced air emissions of volatile
organic compounds by 19 percent since 2000. Also since 2000, our wood products and
cellulose fibers facilities reduced air emissions of particulate matter per ton
of production by 66 percent and nitrogen oxides by 18 percent. This trend is 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.
Cellulose Fibers — Air-Quality Measures
Estimated pounds emitted per ton of production1
| |
2005 |
2006 |
2007 |
2008 |
2009 |
| Nitrogen oxides |
4.5 |
4.4 |
4.7 |
4.4 |
4.2 |
| Particulate matter |
1.5 |
1.3 |
1.2 |
1.1 |
1.0 |
| Sulfur dioxide |
3.3 |
3.4 |
3.3 |
3.1 |
2.7 |
| Total reduced sulfur |
0.2 |
0.1 |
0.1 |
0.1 |
0.1 |
Wood Products Facilities — Air-Quality Measures
Estimated pounds emitted per ton of production
| |
2005 |
2006 |
20071 |
2008 |
2009 |
| Carbon monoxide |
3.0 |
3.2 |
2.2 |
2.1 |
6.22 |
| Volatile organic compounds |
1.5 |
1.4 |
1.5 |
1.5 |
1.5 |
| Particulate matter |
0.8 |
0.8 |
0.9 |
0.5 |
0.5 |
| Nitrogen oxides |
0.6 |
0.6 |
0.6 |
0.6 |
0.6 |
Canadian Criteria Air Contaminants Reporting
Estimated metric tons released from Weyerhaeuser's Canadian manufacturing facilities
|
2004 |
2005 |
2006 |
2007 |
20081 |
| Oxides of nitrogen (as NO2) |
4,965 |
5,246 |
4,494 |
1,298 |
1,115 |
| Carbon monoxide |
16,433 |
14,264 |
14,268 |
3,292 |
2,195 |
| Sulfur dioxide |
1,307 |
1,402 |
1,810 |
1,717 |
2,061 |
| Total particulate matter |
4,258 |
4,066 |
3,849 |
828 |
532 |
| Particulate matter < 10um |
3,130 |
3,000 |
2,881 |
668 |
344 |
| Particulate matter < 2.5um |
2,556 |
2,492 |
2,231 |
568 |
257 |
| Volatile organic compounds |
4,502 |
3,985 |
3,397 |
1,377 |
852 |
| TOTAL Canadian Weyerhaeuser operations2 |
31,465 |
28,963 |
27,818 |
8,505 |
6,755 |
Sustainability in Action
Something is bugging folks in Elkin, N.C.
Weyerhaeuser’s OSB mill in Elkin, N.C., is employing a team of millions to reduce air pollutants emitted from their press. Instead of using a traditional natural-gas-consuming regenerative catalytic oxidizer to get the job done, they’ve installed a biofilter that uses emission-eating bacteria to help the mill meet air-emission standards.
The standards are set by the Maximum Achievable Control Technology rule, known as MACT, which requires a reduction of certain emissions by 90 percent. For Elkin, the rule required a reduction of formaldehyde emissions.
To achieve this goal, the mill opted for a biofilter because it doesn’t require natural gases or carbon fuels in its process and the bacteria are free. The regenerative catalytic oxidizer would have cost half a million dollars per year in fuel cost alone.
The biofilter works by taking OSB press emissions through a series of chambers where the moist environment encourages the growth of bacteria that “eat” the emissions.
“We count the bugs monthly to keep things operating smoothly,” says Billie Caudill, environmental specialist at the Elkin mill. “If the temperature gets too hot, they die. If it gets too cool, they sleep and don’t eat. Every now and then they like a little Miracle Gro fertilizer or five gallons of molasses.”
The destruction removal efficiency rate for this process is impressive — more than 95 percent. And with minimal operational costs, the bugs offer a financially sustainable solution to this environmental challenge, too.
Limited Use of Methyl Bromide
The forest products industry uses methyl bromide, in a targeted and careful way,
to prevent seedling mortality by harmful insects, weeds and disease-causing organisms
in tree-seedling nursery beds, and product shipments as appropriate to meet quarantine
pest control requirements. In accordance with the Montreal Protocol, countries are
phasing out substances that deplete the ozone layer. Methyl bromide is one such
substance.
Within the Protocol, industry can still legally use methyl bromide to prevent the
spread of designated quarantine pests, which can include diseases, insects and invasive
weeds. The ability to use methyl bromide and other chemicals in forest nurseries
enables a very small overall nursery land base to supply the planting stock necessary
to promptly plant thousands of acres of forest land annually, with the corresponding
significant environmental and societal benefits that healthy working forests bring.
Weyerhaeuser uses methyl bromide carefully in targeted and limited applications.
For example, we achieved a 22 percent reduction in pounds of methyl bromide applied
per acre in our Washington and Oregon tree nurseries between 2001 and 2009.
Weyerhaeuser has been a leader in research to develop alternatives to methyl bromide
for forest nursery use in partnership with a number of other agencies and sponsors.
This research has met with some success, but no other fumigants or other alternatives
evaluated to date have shown efficacy across the range of climate, soil type and
pest conditions. As global supplies of methyl bromide continue to decline, the industry
will depend heavily on manufacturers and distributors to step up with effective,
cost-effective, environmentally sound alternatives and the technology to apply them
safely.
