Coal Waste Used to Create Concrete.

• Position: EYE ON ECOLOGY

A sustainable alternative to traditional concrete using fly ash, a waste product of coal-based electricity generation, has been created by researchers at Washington State University, Pullman. The advance tackles a pair of major environmental problems at once by making use of coal production waste and significantly reducing the environmental impact of concrete production.

Xianming Shi, associate professor in the Department of Civil and Environmental Engineering, and graduate student Gang Xu have developed a strong, durable concrete that uses fly ash as a binder and eliminates the use of environmentally intensive cement.

Production of traditional concrete, which is made by combining cement with sand and gravel, contributes between five and eight percent of greenhouse gas emissions worldwide. That is because cement, the key ingredient in concrete, requires high temperatures and a vast amount of energy to produce.

Fly ash, the material that remains after coal dust is burned, meanwhile, has become a significant waste management issue in the U.S. More than 50% ends up in landfills, where it easily can leach into the nearby environment.

While some researchers...