by Trish Barker

The modern age is marked by a nearly insatiable hunger for electricity, and more than half of that power is generated by burning coal. But that electricity is doing more than lighting our homes and driving our computers; its production is also generating toxic mercury. Coal-burning power plants are the largest source of human-generated mercury emissions in the United States.

Scrubbing the hazardous mercury from power plant emissions is not easy. In its elemental form, mercury is not soluble in water and is not readily adsorbed by solids, traits that allow it to elude current techniques for trapping dangerous flue emissions. Recent research, however, has demonstrated that CDEM (a product derived from recycled pulp and paper mill waste) can capture 100 percent of the mercury in flue gases if the mercury is oxidized. Elemental mercury can react with the other components of flue gases, such as chlorine, to form oxidized compounds.

Putting this knowledge to use is complicated by the fact that the mechanisms that change elemental mercury into various oxidized forms are largely unknown. Paul Blowers, an assistant professor of chemical and environmental engineering at the University of Arizona, uses NCSA's two-teraflop IBM p690 cluster to study these reactions in the hopes that a better understanding of them will enable the design of improved strategies for capturing mercury to protect our air, water, and food supplies, and our health.

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Access Online | Posted 7-13-2004