Tunnel kiln combustion-supporting gas inlet system

The utility model relates to a combustion-supporting gas inlet system of a tunnel kiln, which comprises a gas inlet pipe and is characterized by further comprising a waste heat recovery pipe, a heating chamber, a gas conveying pipe and a filtering device. An air inlet of the air inlet pipe is externally connected with an air source, an air outlet of the air inlet pipe is connected with the heating chamber, and the filtering device is installed on the air inlet pipe. A gas inlet of the waste heat recovery pipe is connected with a cooling area of the tunnel kiln, a gas outlet of the waste heat recovery pipe is connected with the heating chamber, a gas inlet of the gas conveying pipe is connected with the heating chamber, and a gas outlet of the gas conveying pipe is connected with a firing area of the tunnel kiln. According to the combustion-supporting gas inlet system of the tunnel kiln, the combustion-supporting gas is not influenced by the environment, and the combustion efficiency and the combustion-support