• Energy and Fuel

Energy and Fuel

The high temperature needed for cement manufacturing makes it an energy-intensive process. The average energy input required to make one ton of cement is 4.65 million Btu. According to the Department of Energy, U.S. cement production accounts for 2.9% of energy consumption—lower consumption levels than iron and steel mills at 7.9% and paper mills at 11.8%. From the PCA publication: U.S. and Canadian Labor-Energy Input Survey 2006, the cement industry has improved energy efficiency by 37.5% from 1972.

To improve the industry’s energy efficiency, PCA member companies partnered with the U.S. Environmental Protection Agency (USEPA) in the development of an Energy Performance Indicator (EPI). The EPI allows plants to compare their performance to that of the entire industry. The EPI is an outgrowth of the USEPA’s Energy Star Industrial Focus program. The tool is intended to help cement plant operators identify opportunities to improve energy efficiency, reduce greenhouse gas emissions, conserve conventional energy supplies, and reduce production costs.

Finding ways to reduce both energy needs and reliance on fossil fuels is a top priority for cement companies. Although coal, petroleum coke, and other fossil fuels have been traditionally burned in cement kilns, many cement companies have turned to energy-rich alternative fuels. Today, many plants meet 20-70% of their energy requirements with alternative fuels. And many of these alternative fuels are consumer wastes or byproducts from other industries. Recovering their energy value in cement making is a safe and proven form of energy recovery.

Because of strict product quality demands, the cement produced from kilns using alternative materials or fuels must be equal in quality to cement from kilns using conventional materials or fuels. Cement plants carefully utilize these alternative fuels and materials so that all types of cement conform to the rigid specifications of the ASTM International.

Burning alternative fuels in cement kilns offers several environmental benefits. This type of energy recovery conserves valuable fossil fuels for future generations while safely destroying wastes that would otherwise be deposited in landfills. From the PCA publication: 2006 U.S. and Canadian Portland Cement Industry: Plant Information Summary, 16 plants used waste oil, and 40 plants in 19 states used scrap tires. Solvents, unrecyclable plastics, and other materials are used as well.

From the PCA publication: U.S. and Canadian Labor-Energy Input Survey 2006, over 65% of the cement plants reporting used one or more waste fuels in 2006. In 1972, no waste fuels were utilized, and in 2006, the energy from waste fuels was 9% of the energy demand at cement plants.

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