Cold and clean coal gas,that is to say the upper coal gas will be reduced the temperature by the indirectly cooler after undertaking the primary electric tar precipitator, the lower coal gas will be reduced the temperature and de-dusting by indirectly cooler and exhausted hear exchanger after de-dusting by the cyclone dust removal.the syngas mixed with lower coal gas and upper coal gas will be reduced the temperature through the indirect cooler,then the tar oil and light oil of the syngas will be filler out through the electric tar precipitator,the syngas which come out from the electric tar precipitator is called cold clean coal gas,it will be transferred to the customer through the gas compressor. The cold clean coal gas is good quality and large scope of utilizing.This kind of coal gas is fit for heat accumulating type burner.