Hot decoking gas, namely upper gas, conducts first-class trapping tar. After entering cyclone dust collectors, lower gas mixes with trapped upper gas and then enters air and gas mixer, ready to be sent to kiln.
  The gas contains a part of tar, light oil and dust. Its temperature is around 250 degrees and its comprehensive heat efficiency is higher than cold clean gas. It applies to the products which do not have high requirement on the quality of gas.