The techndogical flow: Up-stage gas gets into electrical detarrer ,whose work temperature is between 90~150℃. Where the light tar fog-drops and dusts are polarized and then influxed on inside wall of polar tube , and finally flows automatically to light oil jar. The content of light tar is equal to heavy diesel oil. Firstly ,Down-stage gas gets through ash-dropping tube to separate large size dust. Then, gas into the cyclone separation is centrifugally separated and gas temperature is lowered to about 450~550℃. Up-stage gas is mixed with down-stage gas for heating stove through gas pipes.