Cleaner Air on the Fly?

The article reports on how optimizing boiler operation can result in mercury emission reductions by up to 70 percent. Carlos Romero of the Energy Research Center at the Lehigh University says, mercury emitted directly from power plants is not considered harmful, and that elemental mercury becomes highly toxic when it undergoes a series of chemical transformations to become methylmercury. Romero believes that if you leave more unburned carbon in the fly ash, the better able it is to captue oxidized mercury. He suggests grinding the coal more coarsely to increase the level of unburned carbon.