Steel company ArcelorMittal USA's normalized carbon emissions increased 18.6 percent year-on-year, according to the company's latest corporate sustainability report.
In 2010, the steel giant emitted 1.5 tons of CO2 for every ton of steel it produced. In 2011 this figure increased to 1.78 tons of CO2 per ton of steel. The company says that, despite the year-on-year increase, its normalized carbon emissions remain lower than the industry average of 1.8 tons of CO2 per ton of steel in both 2010 and 2011.
The company has a target of reducing this metric by eight percent by 2020 compared to 2007 levels. The report says that the company is working towards this goal through improvements in its equipment and process management capabilities.
On an absolute basis, ArcelorMittal USA was responsible for emitting 27.5 million metric tons of CO2 in 2011. There are no corresponding figures for 2010 in the report.
One carbon reduction initiative that the report highlights is the use of emission control technology. These systems are designed to meet continuous compliance with Maximum Achievable Control Technology, or MACT, requirements set by the EPA and authorized by the Clean Air Act. Last year saw the company invest in its 504 Boiler Project at its Indiana Harbor facility in East Chicago, Ind. This project involved the installation of a boiler which captures blast furnace gas to generate steam. The end result is the displacement of purchased electric energy, thus reducing overall greenhouse gas emissions, the report says.
In 2011, ArcelorMittal's direct energy consumption totaled 266,319,937 GJ, none of which came from renewable sources, the report says. The company's sustainability report does not include comparable figures for 2010 but the report does say that the company's energy use dropped 2.9 percent over the course of the year.
The report also says that ArcelorMittal saved $7.6 million through energy initiatives in 2011. Since 2006, the company says its US facilities have saved more than $151 million though energy efficiency drives. In 2011, 51.3 percent of the total energy used in steel production at its integrated facilities was generated by capturing coke oven and blast furnace gas.
ArcelorMittal says that these accomplishments have made it the first and only steel company to be recognized as an Energy Star partner. The Energy Star Sustained Excellence Award, which was presented in March 2011, is the company's fourth consecutive Energy Star award.
Energy-saving measures implemented in 2011 include a steam trap inspection and repair program at two facilities. The program reduced steam inefficiencies, resulting in reduced emissions and an energy savings of about $150,000 per month.
The company's Columbus, Ohio, facility replaced two 400-horsepower steam generators with one 600-horsepower, low NOx, high efficiency generator, resulting in a reduction in natural gas requirements and a cost savings of about $192,000 per year, the report says.
The report calls steel "the most recycled material in the world," but the amount of steel the company recycles for every ton it produced dropped from 38 percent in 2010 to 33.5 percent in 2011.
Beyond the recycling of steel itself, ArcelorMittal also recycles many co-products and by-products of the steelmaking process: slag is recovered and reused to build roads, create fertilizer or make glass, and iron oxide is salvaged from making tin cans and reused to make magnets, ship ballasts and concrete, the report says.
The company withdrew 1.358 billion cubic meters of water in 2011, but the report does not provide equivalent figures for 2010. According to ArcelorMittal it takes between 13,000 to 23,000 gallons of water to produce a ton of steel, depending on the grade of steel produced. In the company's US operations about 70 percent of the water it withdraws is used for cooling and is returned to source. Any water that comes into contact with steel is treated and returned to source in compliance with state and federal regulations, the company says.
