Reaction furnace for ultralow-temperature flue gas denitration
By setting up vertical partition walls and diversion grilles in ultra-low temperature flue gas denitrification equipment, the mixing stroke between flue gas and ammonia gas and heating it with flue gas heating chamber, the uneven mixing and low reaction efficiency in existing equipment are solved. Problem, significantly improving the denitrification effect.
Patent Information
- Application Number
- CN202421030443.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-13
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-05-13
AI Technical Summary
The existing ultra-low temperature flue gas denitrification equipment has uneven mixing flue gas and ammonia, resulting in uneven reaction areas of the catalytic bed, insufficient initial reaction, low reaction efficiency, and unable to achieve satisfactory denitrification effect.
A reactor for ultra-low temperature flue gas denitrification is designed. By setting up a vertical partition wall inside the furnace body, the furnace chamber is divided into a flue gas heating chamber and a denitrification reaction chamber, and a gas inlet and an ammonia spray head are installed in the flue gas heating chamber. and the diversion grid extend the mixing stroke between flue gas and ammonia, improve the mixing uniformity, and use the flue gas heating chamber to heat the denitrification reaction chamber to ensure the catalytic reaction temperature.
By increasing the mixing uniformity between flue gas and ammonia gas and maintaining an appropriate reaction temperature, the efficiency of the catalytic reaction is significantly improved, the unreacted NOx content in the exhaust gas is reduced, and the denitrification effect is improved.
Smart Images
Figure CN222239568U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of flue gas denitration, in particular to a reaction furnace for ultra-low temperature flue gas denitration. Background Art
[0002] Ultra-low temperature flue gas denitrification technology refers to the use of ammonia water or ammonia gas to remove NO in flue gas under the catalytic conditions of a low temperature range of 120-300℃. x Reduction to nitrogen, the existing ultra-low temperature denitrification equipment introduces fuel gas, flue gas and ammonia water into the furnace body in sequence for heating and then directly uses the catalytic bed to react. In this process, due to the short mixing distance of flue gas and ammonia, the mixing between ammonia and flue gas is not uniform enough. Therefore, when entering the catalytic bed to start the reaction, on the one hand, the reaction area on the catalytic bed is uneven, and on the other hand, the initial reaction is not sufficient. Although there are multiple catalytic beds behind, as the reaction proceeds, the flue gas temperature drops and the overall reaction efficiency decreases, so satisfactory results cannot be achieved. Utility Model Content
[0003] The main technical problem solved by the utility model is to provide a reaction furnace for ultra-low temperature flue gas denitration, which can improve the effect of ultra-low temperature denitration.
[0004] In order to solve the above technical problems, a technical solution adopted by the utility model is: to provide a reactor for ultra-low temperature flue gas denitration, the ultra-low temperature denitration reaction device comprising: a furnace body, a flue gas access pipeline, a gas access port, an ammonia water access port and an exhaust gas pipeline, the gas access port is connected to the gas access pipeline, and the ammonia water access port is connected to the ammonia supply system; a vertical partition wall is arranged inside the furnace body, the vertical partition wall divides the furnace cavity into a flue gas heating cavity and a denitration reaction cavity, the flue gas heating cavity is connected to the top of the denitration reaction cavity, the flue gas access pipeline is connected to the bottom of the flue gas heating cavity, the gas access port is arranged in the middle of the flue gas heating cavity, the gas access port is equipped with an ignition mechanism, the ammonia water access port is arranged at the upper part of the flue gas heating cavity, an ammonia water spray head connected to the ammonia water access port is installed inside the flue gas heating cavity, a plurality of catalytic beds are installed in the denitration reaction cavity, and the exhaust gas pipeline is connected to the bottom of the denitration reaction cavity; the flue gas access pipeline, the exhaust gas pipeline and the catalytic bed are respectively equipped with independent cleaning gas valves.
[0005] In a preferred embodiment of the utility model, the low-temperature denitration reaction device further includes a heat exchanger, the flue gas access pipe is connected to the bottom of the flue gas heating chamber after passing through the heat exchanger, and the tail gas pipe is connected to the bottom of the denitration reaction chamber after passing through the heat exchanger. The flue gas access pipe and the tail gas pipe are both installed with a diversion valve at the position where they enter the heat exchanger and the position where they leave the heat exchanger. The flue gas access pipe and the tail gas pipe are provided with a deashing gas valve dedicated to the diversion valve.
[0006] In a preferred embodiment of the utility model, a drainage slope is provided on the furnace wall at the top of the denitration reaction chamber. The angle between the drainage slope and the horizontal plane is 30°. A guide grid is also installed at the flue gas inlet of the denitration reaction chamber, and the guide grid is also connected to an independent dust cleaning gas valve.
[0007] In a preferred embodiment of the utility model, a turbulent structure is provided on the top of the vertical partition wall, and the turbulent structure is arranged on one side of the smoke heating chamber.
[0008] In a preferred embodiment of the present invention, an induced draft fan is also installed on the exhaust gas duct.
[0009] In a preferred embodiment of the present invention, the bottom area of the flue gas heating chamber is larger than the bottom area of the denitration reaction chamber.
[0010] The beneficial effects of the utility model are as follows: the utility model is an improvement made on the basis of the existing nitration reaction device, and the sequential reaction chamber is changed into two parallel chambers. Thus, on the one hand, the length of the flue is increased, the mixing stroke of the flue gas and the ammonia is improved, and the uniformity of the mixing of the flue gas and the ammonia is effectively improved, so that the flue gas components are evenly dispersed when entering the catalyst bed for reaction, and the effect of the catalytic reaction can be maximized. On the other hand, the flue gas heating chamber can be used to heat the denitration reaction chamber, so that the flue gas can still ensure sufficient reaction temperature when entering the first catalyst bed, thereby ensuring the effect of the subsequent catalytic reaction, improving the efficiency of the reaction as a whole, and significantly reducing the unreacted NO in the tail gas. x The content of molecules can improve the denitrification effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 This is a schematic diagram of the internal structure of a preferred embodiment of the utility model;
[0012] The markings of the components in the accompanying drawings are as follows:
[0013] 1. Flue gas access pipeline, 2. Gas access pipeline, 3. Ammonia supply system, 4. Exhaust gas pipeline, 5. Sprinkler head, 6.
[0014] Vertical partition wall, 7. Drainage slope, 8. Drainage grid, 9. Catalytic bed, 10. Heat exchanger, 11. Induced draft fan, 12.
[0015] Drainage valve, 13. Dust removal valve. DETAILED DESCRIPTION
[0016] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.
[0017] See also Figure 1 , the utility model embodiment includes:
[0018] A reaction furnace for ultra-low temperature flue gas denitration, the ultra-low temperature denitration reaction device comprising: a furnace body, a flue gas access pipe 1, a gas access port, an ammonia water access port and an exhaust pipe 4, the gas access port is externally connected to a gas access pipe 2, the ammonia water access port is externally connected to an ammonia supply system 3; a vertical partition wall 6 is arranged inside the furnace body, the vertical partition wall 6 divides the furnace cavity into a flue gas heating cavity and a denitration reaction cavity, the flue gas heating cavity is connected to the top of the denitration reaction cavity, the flue gas access pipe 1 is connected to the bottom of the flue gas heating cavity, the gas access port is arranged It is located in the middle of the flue gas heating chamber, the gas inlet is equipped with an igniter, the ammonia water inlet is arranged at the upper part of the flue gas heating chamber, the flue gas heating chamber is equipped with an ammonia water spray head 5 connected to the ammonia water inlet, three catalytic beds 9 are installed in the denitration reaction chamber, the exhaust gas pipe 4 is connected to the bottom of the denitration reaction chamber, and the exhaust gas pipe 4 is also equipped with an induced draft fan 11; the flue gas access pipe 1, the exhaust gas pipe 4 and the catalytic bed 9 are respectively equipped with independent cleaning gas valves 13.
[0019] The low-temperature denitration reaction device also includes a heat exchanger 10. The flue gas access pipe 1 is connected to the bottom of the flue gas heating chamber after passing through the heat exchanger 10, and the tail gas pipe 4 is connected to the bottom of the denitration reaction chamber after passing through the heat exchanger 10. A diversion valve 12 is installed at the position where the flue gas access pipe and the tail gas pipe 4 enter the heat exchanger 10 and the position where they leave the heat exchanger 10. A ash cleaning gas valve 13 dedicated to the diversion valve 12 is provided on the flue gas access pipe 1 and the tail gas pipe 4, and the ash cleaning gas valve 13 is connected to the outside of the diversion valve 12. By using the heat exchanger 10, the waste heat of the tail gas can be used to preheat the flue gas access pipe 1 during actual operation, thereby reducing energy consumption and reducing the amount of gas used. The diversion valve 12 can stabilize the gas volume passing through the heat exchanger 10, reduce the fluctuation of the flue gas preheating temperature during preheating, and the ash cleaning gas valve 13 can blow away the ash in the pipe in time to prevent pipe blockage.
[0020] A drainage slope 7 is arranged on the furnace wall at the top of the denitration reaction chamber. The angle between the drainage slope 7 and the horizontal plane is 30°. The reason for using the drainage slope 7 is that after the flue gas and gasified ammonia water enter the denitration reaction chamber through the top driven by high temperature, the farther away from the vertical partition wall 6, the smaller the molecular density is. In this way, directly descending to the catalytic bed 9 will cause uneven reactions in various areas of the catalytic bed 9 below. In this way, the molecular density at the edge position can be enhanced by the drainage slope 7, thereby preventing the problem of uneven local reactions. A guide grid 8 is also installed at the flue gas inlet position of the denitration reaction chamber, and the guide grid 8 is also connected to an independent cleaning gas valve 13. The installation of the guide grid 8 can work synergistically with the drainage slope 7 to further homogenize the distribution of molecules in the chamber and improve the uniformity of the denitration reaction on the catalytic bed 9.
[0021] The top of the vertical partition wall 6 is provided with a turbulent structure, which is arranged on one side of the smoke heating chamber. The turbulent structure can disrupt the gasified ammonia water, so that the ammonia water and the smoke are mixed more evenly and the reaction efficiency is higher.
[0022] The bottom area of the flue gas heating chamber is larger than the bottom area of the denitrification reaction chamber. In actual implementation, the bottom area of the flue gas heating chamber is generally twice the bottom area of the denitrification reaction chamber. This setting is to balance the air pressure at the flue gas inlet and the exhaust gas outlet and reduce the workload of the induced draft fan 11.
[0023] In actual use of this embodiment, the flue gas is introduced into the pipe 1 through the heat exchanger 10 and then enters the bottom of the flue gas heating chamber. Then, the gas and ammonia water are introduced into the flue gas heating chamber in sequence. The gas burns and heats the flue gas and ammonia water, so that the ammonia water is gasified and fully mixed with the flue gas. Then, the ammonia water is homogenized again through the guide grid 8 and enters the catalyst bed 9 for continuous catalytic reaction to convert NO x After being reduced to nitrogen and water, it is led out through the tail gas pipeline 4.
[0024] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A reactor for ultra-low temperature flue gas denitrification, characterized in that: The ultra-low temperature denitration reaction device comprises: a furnace body, a flue gas access pipeline, a gas access port, an ammonia water access port and an exhaust gas pipeline, wherein the gas access port is externally connected to the gas access pipeline, and the ammonia water access port is externally connected to the ammonia supply system; A vertical partition wall is provided inside the furnace body, and the vertical partition wall divides the furnace cavity into a flue gas heating cavity and a denitration reaction cavity. The flue gas heating cavity is connected to the top of the denitration reaction cavity, and the flue gas access pipe is connected to the bottom of the flue gas heating cavity. The gas access port is arranged in the middle of the flue gas heating cavity, and an ignition mechanism is installed at the gas access port. The ammonia water access port is arranged at the upper part of the flue gas heating cavity, and an ammonia water spray head connected to the ammonia water access port is installed inside the flue gas heating cavity. Multiple catalytic beds are installed in the denitration reaction cavity, and the tail gas pipeline is connected to the bottom of the denitration reaction cavity. The flue gas access pipeline, tail gas pipeline and catalyst bed are respectively equipped with independent dust cleaning valves.
2. The ultra-low temperature flue gas denitrification reactor according to claim 1, characterized in that: The low-temperature denitration reaction device also includes a heat exchanger. The flue gas access pipeline passes through the heat exchanger and then is connected to the bottom of the flue gas heating chamber. The tail gas pipeline passes through the heat exchanger and then is connected to the bottom of the denitration reaction chamber.
3. The ultra-low temperature flue gas denitrification reactor according to claim 2, characterized in that: The positions where the flue gas access pipe and the tail gas pipe enter the heat exchanger and the positions where they leave the heat exchanger are both equipped with diversion valves.
4. The ultra-low temperature flue gas denitrification reactor according to claim 2, characterized in that: The flue gas access pipeline and the tail gas pipeline are provided with a dust cleaning gas valve dedicated to the diversion valve.
5. The ultra-low temperature flue gas denitrification reactor according to claim 1, characterized in that: A drainage slope is arranged on the furnace wall at the top of the denitration reaction chamber.
6. The ultra-low temperature flue gas denitrification reactor according to claim 5, characterized in that: The angle between the drainage slope and the horizontal plane is 30°.
7. The ultra-low temperature flue gas denitrification reactor according to claim 5, characterized in that: A guide grid is also installed at the flue gas inlet position of the denitration reaction chamber, and the guide grid is also connected to an independent dust cleaning gas valve.
8. The ultra-low temperature flue gas denitrification reactor according to claim 1, characterized in that: A turbulent flow structure is provided at the top of the vertical partition wall, and the turbulent flow structure is arranged on one side of the smoke heating chamber.
9. The ultra-low temperature flue gas denitrification reactor according to claim 1, characterized in that: An induced draft fan is also installed on the tail gas pipeline.
10. The ultra-low temperature flue gas denitrification reactor according to claim 1, characterized in that: The bottom area of the flue gas heating chamber is larger than the bottom area of the denitration reaction chamber.