Abstract: The exhaust gas discharged by coal thermal drying system of coal preparation plant is one of the sources of atmospheric pollution,and in some urban areas,coal burning is strictly forbidden.Use of clean energy in place of coal has become an inevitable trend.Natural gas,liquefied natural gas（ LNG）,steam and methanol are all ideal clean energy resources.The coal-fired drying system of Tianzhuang plant has now shifted to the use of pipe-line natural gas.An introduction is made in the paper,through citing the Tianzhuang project as an example,to the factors which should be taken into consideration in selection of clean energy,the engineering practice and energy-saving measures.Use of clean energy for coal produces a positive environmental impact and a marked energy conservation result.