| 摘要 |
PROBLEM TO BE SOLVED: To ensure a much larger space by making compact a venturi mixer for recirculating exhaust gas for reducing NOx and a pipe for recirculating the exhaust gas, and prevent a sucking force for the recirculating exhaust gas from becoming sufficient when temperature is high. SOLUTION: A radiant tube combustion device has such an arrangement that fuel gas is alternately supplied to regenerative burners 2a, 2b which are, respectively, mounted to both ends of a radiant tube 1, and that charge and discharge of gas to and from both of the burners 2a, 2b are switched by a four-way valve 3. By providing a communicating pipe 4 for communicating a discharging side of the four-way valve 3 with a charging side thereof and sending high-pressure air to a venturi mixer 5 which is provided in the communicating pipe 4, a portion of the exhaust gas is recirculated to the charging side. |
