An industrial flue gas denitrification device based on pneumatic conveying

Abstract

The present invention relates to an industrial flue gas denitrification device based on pneumatic conveying, comprising an air supply system, a dosing system, a blowing system, an injection pipeline and a PLC process control system. The air supply system provides dry and stable compressed air for the entire device. The dosing system is connected to the blowing system, and the blowing system is connected to the injection pipeline. Compressed air is introduced into the dosing system and the injection system. Denitrification agent particles are transported and stored in a denitrification agent storage bin through the dosing system, and then transported and stored in the blowing system through pneumatic conveying, and sprayed into the flue to be denitrified through the injection pipeline. The PLC process control system is programmed, and processes switching quantities and analog quantities, and sends control signals to keep the device in normal working condition. The present invention achieves the purpose of spraying trace denitrification agent particles into the flue after long-distance transportation for denitrification, and can also realize continuous dosing and spraying, the spraying amount is adjustable, and the discharge of each spray gun is relatively uniform.

Description

Technical Field

[0001] The present invention relates to an industrial flue gas denitrification device based on pneumatic conveying, belonging to the technical field of flue gas purification devices. Furthermore, the present invention relates to a device for continuous dilute phase conveying and particle injection of a solid denitrifying agent, which utilizes pneumatic conveying and automatic control technologies to spray denitrifying agent particles through an injection pipe and a spray gun into the flue to be denitrified. Background Art

[0002] Nitrogen oxides (NO x ) is one of the main pollutants in flue gas produced by boilers and kilns in thermal power plants, steel industry, oil refining industry, glass industry, cement industry, etc. NO in flue gas x It is harmful to human health and can also cause photochemical smog and acid rain. x The control of NOx has attracted more and more attention from the state and related industries. The national and local governments have successively formulated emission control requirements for air pollutants in different industries, including NOx x The control of emission concentration is becoming more and more stringent.

[0003] Currently, industries involving flue gas denitrification, such as thermal power plants and the steel industry, primarily utilize SCR (Selective Catalytic Reduction), SNCR (Selective Non-Catalytic Reduction), and a combination of SCR and SNCR for their back-end denitrification processes. These three commonly used reducing agents all use liquid ammonia, aqueous ammonia, or urea solution. SCR technology boasts a denitrification efficiency of 80-90%, but its core component, the catalyst, is susceptible to poisoning, which affects the effectiveness of the denitrification unit and increases operating costs. Traditional SNCR technology has a denitrification efficiency of 30-60%, and its reaction temperature range is relatively narrow, from 850°C to 1150°C. The combined SCR and SNCR technology offers a denitrification efficiency of 50-80%. However, all three technologies utilize amino-based reducing agents. In industrial applications, excessive denitrification efficiency is often pursued to meet environmental protection requirements, resulting in increased ammonia consumption and, in turn, ammonia slip, causing secondary pollution and equipment corrosion.

[0004] Current SCR and SNCR systems inject liquid reducing agents, making it impossible to directly utilize existing denitrification equipment for injecting solid denitrification agents. While pneumatic conveying is widely used in the metallurgical industry to inject solid bulk materials into reaction systems, the particle size of the particles used in metallurgical injection differs from that of solid denitrification agents. The average particle size of solid denitrification agents is 20-30 μm. Furthermore, the metallurgical industry injects a gas-solid two-phase flow into a liquid environment, such as molten steel, while solid denitrification agents are injected into the flue gas. Furthermore, the two-phase transfer of solid denitrification agents involves dilute-phase pneumatic conveying, while injection involves micro-particle conveying (with a material-gas mixing ratio less than 1). The number of particles per unit mass of compressed air is very small, and the transport patterns of micro-particle conveying differ significantly from those of dilute-phase pneumatic conveying. Therefore, directly using the material injection equipment used in the metallurgical industry cannot achieve the desired transport of micro-solid denitrification agents and their uniform injection within the flue gas.

[0005] The denitrification efficiency depends on the degree of contact between the solid denitrifier and the flue gas. Currently, there is no equipment that can directly achieve this. Therefore, in order to use solid denitrifiers to achieve efficient and continuous denitrification, a set of equipment is required to transport trace denitrifier particles to the spray gun through a pneumatic conveying device, and then inject them into the position to be denitrified through the spray gun to fully mix and react with the flue gas. The spray metering can be adjusted and the spray operation can be carried out continuously. Summary of the Invention

[0006] The purpose of the present invention is to provide an industrial flue gas denitrification device based on pneumatic conveying to achieve the conveying of trace solid denitrification agents and uniform injection at the location to be denitrified, and the conveying amount is adjustable, and the denitrification agent conveying process is efficient and continuous.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] The present invention discloses an industrial flue gas denitrification device based on pneumatic conveying, comprising an air supply system, a dosing system, a spraying system, a spraying pipeline, and a PLC process control system. The dosing system comprises a denitrification agent storage bin, a bin top dust collector, a bin top safety valve, a bin top muffler, a bin top evacuator, a denitrification agent hopper, a bin feeder, and a conveying pipeline. The spraying system comprises a buffer silo, a buffer silo top dust collector, a buffer silo top safety valve, a spray silo, and a spray silo feeder. The spraying pipeline comprises a conveying pipeline and a spray gun. The air supply system provides dry, stable compressed air for the entire device. The dosing system is connected to the spraying system, which is connected to the spraying pipeline. Compressed air is introduced into the dosing system and the spraying system. The spray gun is inserted into the flue to be denitrified.

[0009] Preferably, the denitrification agent hopper is connected to the denitrification agent storage silo feed interface by a feed pipeline, the denitrification agent storage silo tank top is connected to the storage silo tank top dust collector, the storage silo tank top dust collector is connected to the storage silo tank top safety valve and the storage silo tank top evacuator, and the storage silo tank top evacuator is connected to the storage silo tank top muffler. The denitrification agent storage silo tank bottom is connected to the denitrification agent storage silo delivery pipeline, and a storage silo feeder is installed on the denitrification agent storage silo delivery pipeline; the denitrification agent storage silo delivery pipeline is connected to the injection system buffer silo feed interface, the buffer silo tank top is connected to the buffer silo tank top dust collector and the buffer silo tank top vent valve, the buffer silo tank bottom is connected to the tank top feed port of the spray silo through a discharge pipeline, the spray silo tank bottom is connected to the discharge pipeline, and a spray silo feeder is installed on the discharge pipeline. The delivery pipeline of the injection pipeline is connected to the spray silo feeder, and the rear end of the delivery pipeline is connected to the spray gun.

[0010] Preferably, the PLC process control system is programmed according to the process requirements, and processes various switching quantities and analog quantities from the system, sends various switching and analog signals in a timely manner, and controls and adjusts the process through the pneumatic control station. The analog quantities processed include the switching signals of the valves, the level signals of the denitrification agent storage bins, the level signals of the buffer bins, the level signals of the spray bins, the air pressure of each control point, and the gas flow signals.

[0011] Preferably, a feed port is provided at the upper portion of the denitrification agent feeding hopper, and a discharge port is provided at the lower portion, and the discharge port is connected to a feed pipeline of the denitrification agent storage bin.

[0012] Preferably, the air supply system compresses the air or flue gas, removes oil and water, and then delivers it to each air-using point or uses nitrogen. A pressure-stabilizing valve is installed on the compressed air inlet pipeline of the denitrification agent storage tank delivery pipeline and the injection pipeline.

[0013] Preferably, the storage bin feeder and the spray silo feeder both use variable frequency motors.

[0014] Preferably, the bottom of the denitrification agent storage bin is a conical tank bottom with a loose wind structure, and the bottom of the injection system buffer bin and the spray bin is a conical tank bottom.

[0015] Preferably, the denitrification agent storage silo, buffer silo and spray silo are pressure vessels, and the normal operating pressure range is 0~0.6MPa(a).

[0016] Preferably, the bottom discharge pipe of the buffer silo of the spray system is connected to at least two spray silos, a stop valve is installed on the top feed pipeline of each spray silo, and the feed pipelines of all spray silos are connected to the bottom discharge pipe of the buffer silo.

[0017] Preferably, the injection system can be installed on the ground or on a platform near the location to be denitrated.

[0018] Preferably, the number of spray guns is adjustable, influenced by the denitrification equipment being used. The spray guns can be placed on a single side or symmetrically on both sides, with the spray gun diameter ≤ the diameter of the delivery pipe in the injection pipeline. When the number of spray guns on a single side is odd, the upper end of the vertical delivery pipe is connected to the second horizontal delivery pipe. When the number of spray guns on a single side is even, the middle of the vertical delivery pipe is connected to the second horizontal delivery pipe via a diameter-expanding distributor.

[0019] The beneficial effects of the present invention are as follows:

[0020] 1. This invention uses a tank-top evacuator to create negative pressure within the denitrification agent storage bin. Denitrification agent particles enter the denitrification agent storage bin from a tank truck or packaging bag through a denitrification agent hopper, completing the denitrification agent transfer process. This simplifies the feeding process, reduces labor costs, and minimizes the impact of denitrification agent powder on the surrounding environment and workers. Furthermore, the denitrification agent storage bin ensures that incoming denitrification agent is quickly transferred to a dry and sealed environment, reducing the possibility of denitrification agent particles absorbing moisture and agglomerating.

[0021] 2. The present invention introduces compressed air into the denitrification agent storage bin, buffer bin, and spray bin to maintain the pressure of the denitrification agent storage bin, buffer bin, and spray bin within a certain range, thereby promoting the flow of denitrification agent particles to the bottom of the tank, and providing a solution to the problem that the fluidity of denitrification agent particles deteriorates after being stored for a long time.

[0022] 3. The present invention utilizes pneumatic conveying to transport and spray denitrification agent particles, and can realize the transport of trace particles and the regulation of the denitrification agent transport amount by controlling the conveying air volume and the frequency of the feeder.

[0023] 4. The present invention realizes continuous delivery of denitrification agent and multi-point uniform spraying in the area to be denitrified through the delivery pipeline between the denitrification agent storage bin and multiple buffer silos and the valves on the pipeline, as well as the structure of the delivery pipeline and the spray gun, combined with the PLC process control system. The degree of automation is high, and the area to be denitrified can be a negative pressure area or a positive pressure area, and the application range of the device is wide. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the composition of an industrial flue gas denitrification device based on pneumatic conveying according to the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of 4 spray guns;

[0026] Figure 3 It is a schematic diagram of the structure of 6 spray guns;

[0027] In the above figures, 1. air supply system; 2. dosing system; 201. storage tank top muffler; 202. storage tank top evacuator; 203. storage tank top safety valve; 204. storage tank top dust collector; 205. denitrification agent feeding hopper; 206. denitrification agent storage silo; 207. storage silo feeder; 208. denitrification agent storage silo conveying pipeline; 209. denitrification agent storage silo feeding pipeline; 3. injection system; 301. buffer silo tank top dust collector; 302. buffer silo tank top safety valve; 30 3. Buffer silo; 304. Spray silo; 305. Spray silo feeder; 4. Injection pipeline; 401. Conveying pipeline; 4011. Vertical conveying pipe of conveying pipeline; 4012. Vertical conveying pipe expansion distributor; 4013. Horizontal conveying pipe 1; 4014. Bend pipe; 4015. Horizontal conveying pipe 2; 4016. Horizontal conveying pipe expansion distributor; 4017. Vertical conveying pipe of spray gun; 402. Spray gun; 5. PLC process control system; 6. Flue to be denitrified. DETAILED DESCRIPTION

[0028] Below with reference to the accompanying drawings of the present invention, Figures 1-3 , clearly and completely describing the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Directional terms mentioned in the embodiments, such as up, down, front, and back, are only used with reference to the directions in the accompanying drawings and are used to illustrate and not to limit the present invention.

[0029] First embodiment:

[0030] Referring to the accompanying drawings, an industrial flue gas denitrification device based on pneumatic conveying of the present invention includes an air supply system 1, a dosing system 2, a spraying system 3 and a spraying pipe 4. The dosing system 2 includes a denitrification agent storage bin 206, a bin tank top dust collector 204, a bin tank top safety valve 203, a bin tank top muffler 201, a bin tank top evacuator 202, a denitrification agent hopper 205, a bin feeder 207 and a denitrification agent storage bin conveying pipe 208. The spraying system 3 includes a buffer bin 303, a buffer bin tank top dust collector 301, a buffer bin tank top safety valve 302, a spray bin 304 and a spray bin feeder 305. The spraying pipe 4 includes a conveying pipe 401 and a spray gun 402. The air supply system 1 provides dry and stable compressed air for the entire device. The dosing system 2 is connected to the spraying system 3, and the spraying system 3 is connected to the spraying pipe 4. The dosing system 2 and the injection system 3 are fed with compressed air, and the spray gun 402 is inserted into the flue 6 to be denitrified.

[0031] The denitrification agent feeding hopper 205 is connected to the denitrification agent storage bin 206 by a feed pipeline 209. The top of the denitrification agent storage bin 206 is connected to the bin top dust collector 204. The bin top dust collector 204 is connected to the bin top safety valve 203 and the bin top evacuator 202. The bin top evacuator 202 is connected to the bin top muffler 201. The bottom of the denitrification agent storage bin 206 is connected to the denitrification agent storage bin conveying pipe 208, and a storage bin feeder 207 is installed on the denitrification agent storage bin conveying pipe 208; the denitrification agent storage bin conveying pipe 208 is connected to the feed interface of the buffer bin 303 of the injection system 3, the top of the buffer bin 303 is connected to the buffer bin top dust collector 301 and the buffer bin top safety valve 302, the bottom of the buffer bin 303 is connected to the top feed port of the spray bin 304 through the discharge pipeline, the bottom of the spray bin 304 is connected to the discharge pipe, and a spray bin feeder 305 is installed on the discharge pipe; the conveying pipe 401 of the injection pipe 4 is connected to the spray bin feeder 305, and the rear end of the conveying pipe 401 is connected to the spray gun 402.

[0032] Preferably, the PLC process control system 5 is programmed according to the process requirements, and processes various switching quantities and analog quantities from the system, sends various switching and analog signals in a timely manner, and controls and adjusts the process through the pneumatic control station. The analog quantities processed include the switching signal of the valve, the material level signal of the denitrification agent storage bin 206, the material level signal of the buffer bin 303, the material level signal of the spray bin 304, the air pressure of each control point, and the gas flow signal.

[0033] Preferably, the denitrification agent hopper 205 has a feed port at the top and a discharge port at the bottom, and the discharge port is connected to the feed line 210 of the denitrification agent storage bin 206. To further optimize the solution, the denitrification agent hopper 205 is a conical hopper, a small variable frequency wall vibrator is installed on the outer wall of the hopper, a discharge port is opened at the bottom of the conical body of the hopper, and a stop valve and a regulating valve are installed on the denitrification agent storage bin feed line 209 to control the discharge speed of the denitrification agent hopper 205 and the time of starting discharge. The 90-degree elbow on the denitrification agent storage bin feed line 209 is used to change the flow direction, and a 10D elbow is selected. The storage bin tank top evacuator 202 is used to make the pressure in the denitrification agent storage bin 206 lower than the atmospheric pressure, so that the denitrification agent in the denitrification agent hopper 205 can be sucked into the denitrification agent storage bin feed line 209 and then enter the denitrification agent storage bin 206.

[0034] Preferably, the air supply system 1 compresses the air or flue gas and removes oil and water to obtain compressed air, which is then transported to each air-using point. The compressed air after deoiling and dewatering slows down the rate of denitrification agent agglomeration and reduces the pollution to the denitrification agent. Or nitrogen is used as the air source. A pressure-stabilizing valve is installed on the compressed air inlet pipeline of the denitrification agent storage bin delivery pipeline 208 and the injection pipeline 4. Further optimization scheme, the pressure of the compressed air provided by the air supply system 1 is greater than 0.4MPa(a), and the pressure-stabilizing valve controls the wind pressure of the compressed air entering the denitrification agent storage bin delivery pipeline 208 and the injection pipeline 4 to 0.4MPa(a). The function of the pressure-stabilizing valve is to eliminate the influence of fluctuations in the air consumption of other air-using points on the delivery air, and to ensure the stability of the denitrification agent delivery. The device has multiple air use points. The purpose of the compressed air entering the upper part of the denitrification agent storage bin 206 is to increase the discharge speed of the denitrification agent in the storage bin; a loosening air structure can be installed at the bottom of the denitrification agent storage bin 206, and the loosening air here is used to loosen the compacted denitrification agent at the bottom of the storage bin; the purpose of the compressed air entering the buffer bin 303 and the spray bin 304 is to supplement the pressure of the buffer bin 303 and the spray bin 304 to reach the operating pressure; the compressed air entering the denitrification agent storage bin conveying pipe 208 and the injection pipe 4 serves to convey the denitrification agent particles.

[0035] Preferably, the bottom of the denitrification agent storage bin 206 is a conical tank bottom. Further optimization is to use an elliptical-top, conical-bottom steel container. A loose air mechanism is installed near the bottom outlet of the denitrification agent storage bin 206. This loose air mechanism simultaneously delivers loose air to four ventilation points. When denitrification agent particles are stored in the denitrification agent storage bin 206 for a long time, compaction may prevent the particles from being discharged. The loose air mechanism effectively solves this problem.

[0036] Preferably, the number of 90-degree elbows on the denitrification agent storage silo delivery pipe 208 is less than or equal to four. The delivery pipe 401 of the injection pipe 4 uses a 10D or larger diameter 90-degree elbow near the ground, and the elbow diameter on the high-altitude pipeline is less than the elbow diameter on the ground. A further optimization scheme is to use three 6D elbows on the denitrification agent storage silo delivery pipe 208. The delivery pipe 401 of the injection pipe 4 uses a 20D elbow for the 90-degree elbow near the ground, and a 10D elbow for the elbow on the high-altitude pipeline.

[0037] Preferably, the bottoms of the buffer silo 303 and the spray silo 304 of the spraying system 3 are conical tank bottoms. To further optimize the solution, both use elliptical top and conical bottom steel containers.

[0038] Preferably, the denitrification agent storage bin 206, the buffer bin 303 and the spray bin 304 are pressure vessels, and the normal operating pressure range is 0~0.6MPa(a).

[0039] Preferably, the buffer silo 303 of the spraying system 3 has a bottom discharge pipe connected to at least two spray silos 304. A stop valve is installed on the top feed line of each spray silo 304, and the feed lines of all spray silos 304 are connected to the bottom discharge pipe of the buffer silo 303. A further optimized solution is to have two spray silos 304, one for backup and one for use.

[0040] Preferably, the injection system 3 can be installed on the ground or on a platform near the location to be denitrated. As a further optimization solution, the injection system 3 can be installed on a platform near the location to be denitrated when space on site allows.

[0041] Preferably, the number of the spray guns 402 is affected by the denitrification equipment and can be adjusted. The spray guns can be set on one side or symmetrically on both sides, and the diameter of the spray gun is ≯ the diameter of the conveying pipe in the injection pipeline. When the number of spray guns on one side is odd, the upper end of the spray gun vertical conveying pipe 4017 is connected to the horizontal conveying pipe 2 4015. When the number of spray guns on one side is even, the middle of the spray gun vertical conveying pipe 4017 is connected to the horizontal conveying pipe 2 4015 through the horizontal conveying pipe expansion distributor 4016. Further optimization scheme, the number of spray guns 402 is selected to be 4, symmetrically distributed, 2 on each side, the diameter of the conveying pipe 401 of the injection pipeline is 50 mm (inner diameter), and the diameter of the spray gun 402 is 30 mm (inner diameter).

[0042] Second embodiment:

[0043] The difference between this embodiment and the first embodiment is that the loose air structure at the bottom of the denitrification agent storage tank 206 is configured to simultaneously deliver loose air to six ventilation points. The number of 90-degree elbows on the denitrification agent storage tank delivery pipe 208 is four, and 8D elbows are used. The spraying system 3 is installed on the ground near the equipment to be denitrified. The delivery pipe 401 of the injection pipe 4 uses a 15D elbow for the 90-degree elbow on the pipeline near the ground, and a 6D elbow for the elbow on the pipeline at high altitude. The number of spray guns 402 is one, and the diameter of the delivery pipe 401 of the injection pipe is 40 mm (inner diameter), and the diameter of the spray gun 402 is 40 mm (inner diameter).

[0044] The working principle of the present invention is as follows:

[0045] When the denitrification agent storage silo 206 is empty, denitrification agent is added through the denitrification agent hopper 205. The silo top evacuator 202 creates a negative pressure inside the denitrification agent storage silo 206, and the denitrification agent is drawn into the denitrification agent storage silo through the denitrification agent storage silo feed line 209. A small variable frequency wall vibrator is installed on the outer wall of the denitrification agent hopper 205 to prevent the accumulation of denitrification agent particles inside the denitrification agent hopper 205. The air supply system 1 provides compressed air and loosening air to the denitrification agent storage silo 206, ensuring that the denitrification agent in the denitrification agent storage silo 206 smoothly falls into the storage silo feeder 207 and then into the denitrification agent storage silo delivery pipe 208. The air supply system 1 provides pneumatic conveying air to the denitrification agent storage silo delivery pipe 208, transporting the denitrification agent in the denitrification agent storage silo 206 to the buffer silo 303. The denitrification agent in the buffer silo 303 enters the spray silo 304 under the action of gravity. All the spray silos 304 contain a certain level of denitrification agent, and the denitrification agent is sprayed and transported in turn. When one of the spray silos 304 is about to be empty, it is switched to another spray silo 304 for spraying and transporting the denitrification agent, and the previous empty spray silo 304 is replenished at the same time. When the buffer silo 303 is about to be empty, it is directly replenished from the denitrification agent storage bin 206, which does not affect the spraying and transporting of the denitrification agent from the spray silo 304. Through the horizontal pipes, bends, vertical pipes, expansion distributors and spray guns of the injection pipeline 4, the direction of the conveying air and the denitrification agent particles is changed, and the denitrification agent particles are evenly injected into the area to be denitrified to complete the flue gas denitrification. By controlling the air volume of the conveying pipeline 401 and the frequency of the spray silo feeder 305, the conveying amount of the denitrification agent particles can be changed. The operations of replenishing, cutting tanks, and regulating pressure during the operation of the device all rely on the PLC process control system 5. The PLC process control system 5 processes various signals in sequence according to the programming, and then gives corresponding control signals to realize the above functions of the device.

[0046] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various improvements and modifications made by ordinary technicians in this field to the technical solutions of the present invention should fall within the scope of protection determined by the claims of the present invention.

Claims

1. An industrial flue gas denitrification device based on pneumatic conveying, comprising an air supply system, a dosing system, a blowing system, an injection pipeline, and a PLC process control system. The dosing system includes a denitrification agent storage bin, a bin top dust collector, a bin top safety valve, a bin top muffler, a bin top evacuator, a denitrification agent hopper, a bin feeder, and a conveying pipeline. The blowing system includes a buffer silo, a buffer silo top dust collector, a buffer silo top safety valve, a spray silo, and a spray silo feeder. The injection pipeline includes a conveying pipeline and a spray gun. The air supply system provides dry, stable compressed air for the entire device. The dosing system is connected to the blowing system, which is connected to the injection pipeline. Compressed air is introduced into the dosing system and the blowing system. The spray gun is inserted into the flue to be denitrified. The denitrification agent hopper is connected to the denitrification agent storage silo feed interface by a feed pipeline, the denitrification agent storage silo tank top is connected to the storage silo tank top dust collector, the storage silo tank top dust collector is connected to the storage silo tank top safety valve and the storage silo tank top evacuator, the storage silo tank top evacuator is connected to the storage silo tank top muffler, the denitrification agent storage silo tank bottom is connected to the denitrification agent storage silo delivery pipeline, the denitrification agent storage silo delivery pipeline is installed on the denitrification agent storage silo feeder, the denitrification agent storage silo delivery pipeline is connected to the injection system buffer silo feed interface, the cache silo tank top is connected to the cache silo tank top dust collector and the cache silo tank top safety valve, the cache silo tank bottom is connected to the tank top feed port of the spray silo through a discharge pipeline, the spray silo tank bottom is connected to the discharge pipe, the spray silo feeder is installed on the discharge pipe, the delivery pipe of the injection pipe is connected to the spray silo feeder, and the rear end of the delivery pipe is connected to the spray gun; The PLC process control system is an integrated circuit module. The PLC process control system is programmed according to process requirements and processes various switching quantities and analog quantities from the system, sends various switching and analog signals in a timely manner, and controls and adjusts the process through the pneumatic control station. The analog quantities processed include valve switching signals, denitrification agent storage bin material level signals, buffer bin material level signals, spray agent bin material level signals, and gas pressure and gas flow signals at each control point. The air supply system compresses air or flue gas, removes oil and water, and then delivers it to each air-using point, or uses nitrogen. A pressure-stabilizing valve is installed on the compressed air inlet pipeline of the denitrification agent storage tank delivery pipeline and the injection pipeline; the pressure of the compressed air provided by the air supply system is greater than 0.4 MPa(A), and the pressure-stabilizing valve controls the compressed air pressure entering the denitrification agent storage tank delivery pipeline and the injection pipeline to be 0.4 MPa(A); The bottom of the denitrification agent storage bin is a conical tank bottom with a loose air structure at the bottom; the loose air structure simultaneously delivers loose air at four ventilation points; The spray gun can be set on one side or symmetrically on both sides, and the diameter of the spray gun is ≯ the diameter of the conveying pipe in the spraying pipe; when the number of spray guns on one side is odd, the upper end of the vertical conveying pipe of the spray gun is connected to the second horizontal conveying pipe; when the number of spray guns on one side is even, the middle of the vertical conveying pipe of the spray gun is connected to the second horizontal conveying pipe through the horizontal conveying pipe diameter expansion distributor; The denitrification agent storage bin, buffer silo and spray silo are pressure vessels, and the normal operating pressure range is 0 to 0.6 MPa (A).

2. The industrial flue gas denitrification device based on pneumatic conveying according to claim 1 is characterized in that: The denitrification agent feeding hopper has a feed port at the top and a discharge port at the bottom, and the discharge port is connected to a feed pipeline of the denitrification agent storage bin.

3. The industrial flue gas denitrification device based on pneumatic conveying according to claim 1, characterized in that: Both the storage silo feeder and the spray silo feeder use variable frequency motors.

4. The industrial flue gas denitrification device based on pneumatic conveying according to claim 1, characterized in that: The bottoms of the buffer silo and the spray silo of the injection system are conical tank bottoms.

5. The industrial flue gas denitrification device based on pneumatic conveying according to claim 1 is characterized in that: The discharge pipe at the bottom of the buffer silo of the spray system is connected to at least two spray silos, and a stop valve is installed on the top feed pipeline of each spray silo.

6. The industrial flue gas denitrification device based on pneumatic conveying according to claim 1, characterized in that: The injection system can be installed on the ground or on a platform near the flue to be denitrified.

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