Integrated coal-fired flue gas desulfurization and denitrification device

Abstract

The integrated coal-fired flue gas desulfurization and denitrification device comprises a denitrification assembly, a desulfurization assembly and a control assembly, the denitrification assembly comprises a first static mixer, a second static mixer and a catalytic reactor, and a main gas inlet of the first static mixer is connected with an ammonia gas source; a gas filling port of the first static mixer is connected with an air source, a gas outlet of the first static mixer is connected with a main gas inlet of the second static mixer, a gas filling port of the second static mixer is connected with a flue gas source, a gas outlet of the second static mixer is connected with a first gas conveying pipe, and the catalytic reactor comprises a reaction cylinder. The reaction cylinders are symmetrically arranged, the top ends of the reaction cylinders are provided with gas inlet ends, the bottom ends of the reaction cylinders are provided with gas outlet ends, the gas outlet ends and the gas inlet ends are provided with three-way electric reversing air valves, and one end of the first gas conveying pipe is connected with gas inlets of the three-way electric reversing air valves at the gas inlet ends of the reaction cylinders.

Description

Technical Field

[0001] The utility model belongs to the technical field of desulfurization and denitrification, and specifically relates to an integrated coal-fired flue gas desulfurization and denitrification device. Background Art

[0002] At present, the core of the integrated desulfurization and denitrification technology widely used at home and abroad lies in the organic combination of wet flue gas desulfurization and selective catalytic reduction denitrification technology. Specifically, wet flue gas desulfurization technology widely uses lime or limestone as a desulfurizer, that is, the calcium method, and its desulfurization efficiency is excellent, generally exceeding 90%. Selective catalytic reduction denitrification technology is known for its efficient denitrification ability, and the denitrification rate is usually between 70% and 90%. This technical system has matured and has been widely used and verified around the world, especially in developed countries.

[0003] However, it is worth noting that as the catalyst ages, the technical system may face the problem of increased concentrations of nitrogen oxides and ammonia in the exhaust gas. Therefore, regular inspection and maintenance are essential to ensure its continued stable operating performance. In addition, the catalyst replacement process is often accompanied by the shutdown of the production line, which undoubtedly poses a significant constraint on production efficiency and equipment utilization. In view of this, the utility model proposes an integrated coal-fired flue gas desulfurization and denitrification device. The device is designed to achieve continuous and uninterrupted operation of the desulfurization and denitrification process, fundamentally solving the problem of production interruptions caused by shutdowns to replace catalysts in traditional methods, and can effectively improve production efficiency and equipment utilization.

[0004] Currently, no effective solution has been proposed for the problems in the related technologies. Utility Model Content

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an integrated coal-fired flue gas desulfurization and denitrification device, comprising a denitrification component, a desulfurization component and a control component, the denitrification component comprising a first static mixer, a second static mixer and a catalytic reactor, the main air inlet of the first static mixer is connected to an ammonia source, the air supply port of the first static mixer is connected to an air source, the air outlet of the first static mixer is connected to the main air inlet of the second static mixer, the air supply port of the second static mixer is connected to a flue gas source, the air outlet of the second static mixer is connected to a first air supply pipe, the catalytic reactor comprises a reaction cylinder, the reaction cylinder is symmetrically arranged, the top end of the reaction cylinder is provided with an air inlet end, the bottom end of the reaction cylinder is provided with an air outlet end, the air outlet end and the air inlet end are both installed with a three-way electric reversing air valve, one end of the first air supply pipe is connected to the air inlet of the three-way electric reversing air valve at the air inlet end of the reaction cylinder, and the air outlet of the three-way electric reversing air valve at the air outlet end of the reaction cylinder is connected to the second air supply pipe;

[0006] The control component includes an ammonia sensor, a nitrogen oxide sensor and a controller. The ammonia sensor and the nitrogen oxide sensor are respectively installed on the second gas pipeline body. The controller is respectively electrically connected to the ammonia sensor, the nitrogen oxide sensor and the valve motor driver of the three-way electric reversing air valve.

[0007] As an optimal technical solution of the utility model, the desulfurization component includes a tower body, the top of the tower body is provided with an exhaust port, one side of the bottom of the tower body is provided with a flue gas inlet, the flue gas inlet is connected to the second gas pipe, and a sprayer and a demister are respectively provided inside the tower body.

[0008] As a preferred technical solution of the utility model, the air inlet of the first static mixer, the air inlet of the second static mixer, and the air inlet and outlet of the three-way electric reversing air valve at the air inlet and outlet ends of the reaction cylinder are all equipped with pressurized fans.

[0009] As a preferred technical solution of the utility model, the reaction cylinder comprises a cylinder body, and a catalyst bed is evenly installed inside the cylinder body.

[0010] As a preferred technical solution of the utility model, a rectifying grid is installed inside the cylinder at the top of the catalyst bed.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] The utility model adopts two symmetrically arranged reaction tube structures, and is equipped with a three-way electric reversing air valve at the air inlet and outlet ports of each reaction tube. The control mechanism can monitor the concentration levels of nitrogen oxides and ammonia in the exhaust gas after denitration treatment in real time and accurately, and evaluate the working efficiency and aging status of the catalyst bed in the reaction tube by comparing and analyzing with the preset threshold value. Once the catalyst bed shows signs of aging, that is, its performance cannot meet the established exhaust gas purification standards, the control mechanism automatically controls the three-way electric reversing air valve to switch the flue gas path, and then activates the spare reaction tube for exhaust gas treatment, thereby ensuring the continuous and uninterrupted operation of the entire treatment process. It solves the problem of shutdown and production suspension that has to be faced in traditional methods due to shutdown to replace the catalyst bed, significantly improves production efficiency and equipment utilization, and reflects the emphasis and pursuit of industrial production continuity, stability and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0014] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0015] Figure 2 It is a schematic diagram of the cross-sectional structure of the reaction tube in the utility model;

[0016] In the figure: 1. first static mixer; 2. second static mixer; 3. first gas pipeline; 4. reaction cylinder; 5. air inlet; 6. air outlet; 7. three-way electric reversing air valve; 8. second gas pipeline; 9. ammonia sensor; 10. nitrogen oxide sensor; 11. rectifier grid; 12. tower body; 13. flue gas inlet; 14. exhaust port; 15. sprayer; 16. demister; 17. pressurized fan; 18. cylinder body; 19. catalyst bed. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] Example

[0019] See also Figure 1-2The utility model provides the following technical solutions: an integrated coal-fired flue gas desulfurization and denitrification device, including a denitrification component, a desulfurization component and a control component, the denitrification component includes a first static mixer 1, a second static mixer 2 and a catalytic reactor, the main air inlet of the first static mixer 1 is connected to an ammonia source, the air filling port of the first static mixer 1 is connected to an air source, the air outlet of the first static mixer 1 is connected to the main air inlet of the second static mixer 2, the air filling port of the second static mixer 2 is connected to a flue gas source, the air outlet of the second static mixer 2 is connected to a first air delivery pipe 3, the catalytic reactor includes a reaction tube 4, the reaction tube 4 is symmetrically arranged, the top end of the reaction tube 4 is provided with an air inlet end 5, the bottom end of the reaction tube 4 is provided with an air outlet end 6, the air outlet end 6 and the air inlet end The first gas pipe 3 is connected to the air inlet of the three-way electric reversing air valve 7 at the air inlet end 5 of the reaction tube 4, and the air outlet of the three-way electric reversing air valve 7 at the air outlet end 6 of the reaction tube 4 is connected to the second gas pipe 8; the control component includes an ammonia sensor 9, a nitrogen oxide sensor 10 and a controller, and the ammonia sensor 9 and the nitrogen oxide sensor 10 are respectively installed on the pipe body of the second gas pipe 8, and the controller is respectively electrically connected to the ammonia sensor 9, the nitrogen oxide sensor 10 and the valve motor driver of the three-way electric reversing air valve 7. In this embodiment, a symmetrical double reaction tube 4 structure is adopted, and the air inlet end 5 and the air outlet end 6 of each reaction tube 4 are equipped with a three-way electric reversing air valve 7. The control mechanism can monitor the concentration of nitrogen oxides and ammonia in the tail gas after denitration treatment in real time, and compare and analyze it with the preset threshold value to evaluate the working efficiency and aging condition of the catalyst bed 19 in the reaction tube 4. Once the catalyst bed 19 shows signs of aging, the control mechanism will immediately and automatically operate the three-way electric reversing air valve 7 to quickly switch the flue gas flow path and activate the spare reaction cylinder 4 for exhaust gas treatment to ensure that the entire treatment process can run continuously, stably and uninterruptedly.

[0020] In order to ensure the desulfurization efficiency, wet desulfurization is adopted. In this embodiment, as a preferred technical solution of the utility model, the desulfurization component includes a tower body 12, an exhaust port 14 is arranged at the top of the tower body 12, a flue gas inlet 13 is arranged at one side of the bottom of the tower body 12, the flue gas inlet 13 is connected to the second gas pipeline 8, and a sprayer 15 and a demister 16 are respectively arranged inside the tower body 12.

[0021] In order to pressurize the gas to complete the desulfurization and denitrification process, in this embodiment, as a preferred technical solution of the utility model, the gas inlet of the first static mixer 1, the gas inlet of the second static mixer 2, and the gas inlet and outlet of the three-way electric reversing air valve 7 at the gas inlet end 5 and the gas outlet end 6 of the reaction tube 4 are all equipped with a pressurized fan 17.

[0022] In order to ensure that the diluted ammonia and flue gas accelerate the reaction rate, in this embodiment, as a preferred technical solution of the utility model, the reaction cylinder 4 includes a cylinder body 18, and a catalyst bed 19 is evenly installed inside the cylinder body 18.

[0023] In order to evenly distribute the mixed gas and make it evenly pass through the catalyst bed 19, in this embodiment, as a preferred technical solution of the utility model, a rectifying grid 11 is installed inside the cylinder 18 at the top of the catalyst bed 19.

[0024] In summary, with the help of the technical solution of the utility model, the effective mixing and dilution of air and high-concentration ammonia is achieved through the first static mixer 1. Subsequently, the diluted ammonia is mixed with the coal-fired flue gas through the second static mixer 2 and reacts. In this process, the three-way electric reversing air valve 7 opens the air inlet end 5 and the air outlet end 6 of the reaction tube 4 on one side, and closes the air outlet end 6 and the air inlet end 5 of the reaction tube 4 on the other side. At the same time, the pressurized fan 17 of the first gas pipeline 3 pressurizes the mixed gas and sends it into the reaction tube 4 with the air inlet end 5 and the air outlet end 6 opened. Inside the reaction tube 4, the rectifying grid 11 ensures that the mixed gas is evenly distributed and passes through the catalyst bed 19 evenly, so that under the catalytic action of the catalyst in the catalyst bed 19, ammonia reacts with the flue gas to generate nitrogen and water. The reaction product then enters the desulfurization tower body 12 through the three-way electric reversing air valve 7 at the air outlet end 6 of the reaction tube 4 and the second gas pipeline 8. To ensure the compliance of the exhaust gas, an ammonia sensor 9 and a nitrogen oxide sensor 10 are installed on the second gas pipeline 8 to monitor the concentration of ammonia and nitrogen oxides in the exhaust gas in real time. Once it is found that the long-term use of a certain side of the reaction tube 4 has caused the catalyst to age, causing the concentration of ammonia and nitrogen oxides in the exhaust gas to exceed the standard, the sensor will immediately convert the detected information into an electrical signal and transmit it to the controller. The controller immediately responds and controls the two three-way electric reversing air valves 7 to close the air inlet 5 and the air outlet 6 of the problematic reaction tube 4, and at the same time start the other side of the reaction tube 4 to continue working. Subsequently, the catalyst bed 19 in the aged reaction tube 4 is replaced by the staff.

[0025] The gas entering the desulfurization tower body 12 is then treated by the desulfurizer sprayed by the sprayer 15, which reacts with the flue gas after denitration to achieve desulfurization. Finally, the demister 16 is used to remove water vapor and liquid in the flue gas after desulfurization, thereby completing the entire denitration and desulfurization process.

[0026] Finally, it should be noted that in the present utility model, unless otherwise clearly stipulated and limited, terms such as "installation", "setting", "connection", "fixation", and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the utility model according to the specific circumstances.

[0027] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. An integrated coal-fired flue gas desulfurization and denitrification device, comprising a denitrification component, a desulfurization component and a control component, characterized in that: The denitration component comprises a first static mixer (1), a second static mixer (2) and a catalytic reactor, wherein the main air inlet of the first static mixer (1) is connected to an ammonia source, the air supply port of the first static mixer (1) is connected to an air source, the air outlet of the first static mixer (1) is connected to the main air inlet of the second static mixer (2), the air supply port of the second static mixer (2) is connected to a flue gas source, the air outlet of the second static mixer (2) is connected to a first air delivery pipe (3), and the catalytic reactor comprises a reactor The reaction cylinder (4) is symmetrically arranged, the top of the reaction cylinder (4) is provided with an air inlet end (5), the bottom of the reaction cylinder (4) is provided with an air outlet end (6), the air outlet end (6) and the air inlet end (5) are both installed with a three-way electric reversing air valve (7), one end of the first air supply pipe (3) is connected to the air inlet of the three-way electric reversing air valve (7) of the air inlet end (5) of the reaction cylinder (4), and the air outlet of the three-way electric reversing air valve (7) of the air outlet end (6) of the reaction cylinder (4) is connected to the second air supply pipe (8); The control component comprises an ammonia sensor (9), a nitrogen oxide sensor (10) and a controller. The ammonia sensor (9) and the nitrogen oxide sensor (10) are respectively installed on the pipe body of the second gas transmission pipe (8). The controller is respectively electrically connected to the ammonia sensor (9), the nitrogen oxide sensor (10) and the valve motor driver of the three-way electric reversing air valve (7).

2. The integrated coal-fired flue gas desulfurization and denitrification device according to claim 1, characterized in that: The desulfurization component comprises a tower body (12), the top of the tower body (12) is provided with an exhaust port (14), a bottom side of the tower body (12) is provided with a flue gas inlet (13), the flue gas inlet (13) is connected to a second gas pipeline (8), and a sprayer (15) and a demister (16) are respectively provided inside the tower body (12).

3. The integrated coal-fired flue gas desulfurization and denitrification device according to claim 1 is characterized in that: The air inlet of the first static mixer (1), the air inlet of the second static mixer (2), and the air inlet and air outlet of the three-way electric reversing air valve (7) at the air inlet end (5) and the air outlet end (6) of the reaction cylinder (4) are all equipped with a pressurized fan (17).

4. The integrated coal-fired flue gas desulfurization and denitrification device according to claim 1, characterized in that: The reaction cylinder (4) comprises a cylinder body (18), and a catalyst packed bed (19) is evenly installed inside the cylinder body (18).

5. The integrated coal-fired flue gas desulfurization and denitrification device according to claim 4 is characterized in that: A rectifying grid (11) is installed inside the cylinder (18) at the top of the catalyst packed bed (19).

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