Alcoa Cuts GHG Emissions 44% from 1990, Misses Mercury, Water Targets

by | May 7, 2010

Alcoa continued to reduce its absolute greenhouse gas (GHG) emissions in 2009, achieving a 44 percent cut from 1990 levels, compared to a reduction of 36 percent through 2008, according to the company’s 2009 Sustainability Report. The aluminum manufacturer attributed a large portion of the 2009 improvement to lower production capacity.

Starting in 2010, Alcoa will track GHG reductions that are indexed to production to eliminate annual variations due to either growth or reductions.

Alcoa continues to reduce perfluorocarbons (PFCs) in its smelting process and is looking for opportunities to reduce energy intensity in each of its processes and assoicated indirect CO2 emissions. As an example, process improvements in the Global Primary Products group reduced direct GHG emissions by more than 1 million tons in 2009.

For the first time, the company is including an annual reduction target — based on PFC reductions and energy efficiency across all businesses — as a component of its 2010 incentive compensation program.

The company also continues to drive energy efficiency efforts at its plants. Alcoa’s electrical energy requirement for smelters has dropped from 15 kWh per kilogram in 2000 to 13.3 kWh per kilogram today.

Renewable energy is also on Alcoa’s agenda. The company completed three solar energy system installations in 2007.

Alcoa also purchased enough renewable energy certificates (RECs) to power four of its administrative offices in the United States, avoiding the emissions of more than 6.3 million kilograms (13.9 million pounds) of carbon dioxide annually.

Alcoa said the economic situation in 2009 did not allow the company to invest capital in water reduction projects. Overall, reduction in freshwater use versus 2000 levels improved to 29 percent in 2009, but this was largely due to idled capacity at some of its primary metal production.

Still, it was short of its objective of a 70 percent reduction. Alcoa notes the reduction is still significant since it had doubled production over that time period.

The company’s new long-term goal will focus on fresh water use intensity within each business. From a 2005 baseline, each business targets an average reduction of water-use intensity of 10 percent by 2020 and 25 percent by 2030.

Reducing waste generation is another big focus area. If waste generation is not preventable, Alcoa will reuse the waste or make it useable for other industries to use. As an example, the company turns spent pot lining (SPL) — the carbon and refractory lining of aluminum smelting pots that have reached the end of their service life — into a raw material for other industries including cement manufacturers.

The company also uses recycled materials. As an example, Alcoa uses a waste product from the petroleum refining industry, petroleum coke, as a raw material to form the anodes for its electrolytic process. It also purchases coal tar pitch, a by-product of the steel industry, as the binder for the anodes.

In 2009, Alcoa purchased and recycled 553,000 tons of aluminum scrap. The company operates one of the largest used beverage (UBC) can recycling facilities, which was recently upgraded to increase its recycling capacity by 50 percent.

In early 2008, Alcoa announced a goal to raise the UBC recycling rate in North America to 75 percent by 2015 from 54 percent. This move is expected to save the industry the electricity equivalent of two average-size coal-fired power plants and prevent more than 11 million metric tons of carbon dioxide emissions a year.

The company says progress in reducing its emissions including mercury in 2009 was impacted by the curtailment of some of its primary metal production. As an example, the company set goals to reduce mercury emissions 80 percent by 2008 and 90 percent by 2010, but only posted a 4 percent decline. The company attributes this result to many factors including the variability in the levels of mercury naturally occurring in the bauxite it processes.

The revised goal is to reduce mercury emission intensity 80 percent by 2020 and 90 percent by 2030, based on a 2005 baseline. The company no longer has corporate reduction goals for VOC, NOx and SO2 emissions, but rather each business will work on reductions.

Other new goals, from a 2005 baseline, include:

— Reducing total carbon dioxide equivalent (CO2e) intensity 20 percent by 2020 and 30 percent by 2030.

— 10 percent reduction in the energy intensity of primary operations by 2020 and 15 percent by 2030.

— 20 percent reduction in the energy intensity of all other businesses by 2020 and 30 percent by 2030.

— 20 percent reduction in bauxite residue land requirements per million metric tons of alumina produced by 2020 and 40 percent by 2030

— Recycle or reuse 15 percent of residue generated by 2020 and 30 percent by 2030.

— Recycle or reuse 75 percent of remaining waste streams by 2020 and 100 percent by 2030.

Here’s a chart showing Alcoa’s water use from 2000 to 2009.

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