一种烟气自循环辐射管装置
By controlling the oxygen content of the mixed gas through the Laval tube and air heat exchanger in the flue gas self-circulation device, the problems of uneven flue gas flow and high NOx emissions in the radiant tube are solved, achieving efficient low NOx combustion and energy-saving effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ANGANG STEEL CO LTD
- Filing Date
- 2025-07-09
- Publication Date
- 2026-07-17
AI Technical Summary
The uneven flow of flue gas in existing radiant tubes leads to localized high temperatures, high NOx emissions, and safety hazards. Furthermore, existing flue gas recirculation technologies cannot effectively control the mixing volume and have low efficiency.
A flue gas self-circulation device is adopted, which mixes high-temperature flue gas and combustion air through a Laval tube. The oxygen content of the mixed gas is controlled at 15% to 21% by using the Laval injection principle, and the mixing amount is adjusted by a flue gas regulating valve. Combined with an air heat exchanger, the combustion air is preheated.
It achieves efficient and stable low-NOx combustion of radiant tubes, saving more than 10% in energy and reducing NOx generation by more than 5%, thus improving combustion efficiency and safety.
Smart Images
Figure CN224516777U_ABST
Abstract
Claims
1. A flue gas self-circulation radiant tube apparatus comprising a radiant tube, a burner, a mixed gas connection pipe, a laval pipe, a hot air connection pipe, a flue gas return pipe, a flue gas regulating valve, a flue gas pipe, a cold air connection pipe, and an air heat exchanger, characterized in that, The two ends of the radiant tube are connected to a burner and a flue gas pipe, respectively. An air heat exchanger is installed inside the side of the radiant tube connected to the flue gas pipe. The inlet and outlet ends of the air heat exchanger are connected to a cold air connection pipe and a hot air connection pipe, respectively. The outlet of the hot air connection pipe is connected to a Laval tube, the outlet of the Laval tube is connected to a mixed gas connection pipe, and the outlet of the mixed gas connection pipe is connected to the burner side of the radiant tube. A flue gas return pipe is connected between the flue gas pipe and the Laval tube.
2. A flue gas self-circulation radiant tube arrangement according to claim 1, characterized in that An oxygen analyzer is installed on the gas mixing connection pipe.
3. A flue gas self-circulation radiant tube apparatus according to claim 1, characterized in that, A flue gas regulating valve is installed on the flue gas return pipe.
4. A flue gas self-circulation radiant tube arrangement according to claim 3, characterized in that The flue gas regulating valve controls the oxygen content of the mixed gas in the mixed gas connecting pipe to be between 15% and 21%.
5. A flue gas self-circulation radiant tube arrangement according to claim 1, characterized in that, The flue gas return pipe has sloping ends at both ends, with a slope angle of 10° to 60°. One end of the flue gas return pipe that connects to the Laval tube extends into the center of the Laval tube, with the sloping end facing away from the airflow direction. The other end of the flue gas return pipe that connects to the flue gas pipe extends into the center of the flue gas pipe, with the sloping end facing the airflow direction.