the present process produces a clean burning coal from low grade coal and has a higher heating value per unit mass , as compared to the feed stock coal . the clean coal may be used in coal - fired power plants , industrial boilers , and homes since it produces fewer or none of the emissions commonly associated with coal burning devices . the process treats coal prior to its combustion and removes about 90 percent of the pollutants . these pollutants are removed within 6 to 18 minutes , many of which may be recycled into products such as roofing tar , chemical feed stocks , and light hydrocarbons that can be used as gaseous fuels . the final product is suitable for use in homes where coal is used for cooking and heating , and significantly improves the health of those who have previously been exposed to toxic fumes from burning uncleaned coal in their homes . the process is fueled by its own by - products , recycles heat , and reduces coal weight to save energy in transporting it to the user .