It is possible to remove most of the sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate matter (PM) emissions from the coal-burning process. For example, various techniques are used in a coal preparation plant to reduce the amount of non-combustible matter (i.e. ash) in the coal prior to burning. During combustion, fluidized bed combustion is used to reduce sulfur dioxide emissions. After burning, particulate matter (i.e. ash and dust) can be reduced using an electrostatic precipitator and sulfur dioxide emissions can be further reduced with flue-gas desulfurization. Trace amounts of radionuclides are more difficult to remove.