These technologies are the keys in restoring Midwestern coal to its strong competitive position in large coal markets. A vigorous research and development effort is under way to tackle the sulfur problem. CCT projects remove sulfur before, during and after coal combustion. Sulfur in coal takes two distinct forms. The second is organic sulfur, which is chemically bound in the molecular structure of coal itself.
Pyritic sulfur is relatively easy to remove.
Since pyrite particles are much heavier than coal itself, most pyrite is removed through washing before coal is shipped. Coal washing has contributed greatly to the reduction of sulfur content. The remaining organic sulfur is a problem. Ordinary coal washing cannot remove it. Under the 1977 revisions to the Clean Air Act, all new coal fired units have to be equipped with emission control devices.