A denitration system for a thermal power boiler

Abstract

This invention relates to the field of waste gas treatment technology, specifically to a denitrification system for a thermal power boiler. The system includes an insulated box with a heater mounted on its side wall. A denitrification box is installed inside the insulated box. A second drain outlet and an air inlet pipe are located on the side wall of the insulated box. A first drain outlet is located at the bottom of the insulated box. A first discharge mechanism is installed on both the first and second drain outlets. A second discharge mechanism is located on the outer wall of the denitrification box, inside the insulated box. A lid is detachably connected to the top of the denitrification box. An inlet valve is located on one side of the lid's top, and an exhaust valve is located on the other side. A first denitrification mechanism is located in the middle of the lid. An air guide pipe is located on one side of the top of the insulated box. A filter screen is installed at the air inlet end of the air guide pipe, and the other end of the air guide pipe is connected to the first denitrification mechanism. This invention facilitates the recovery and utilization of waste heat from flue gas, making it more energy-efficient and environmentally friendly. It also facilitates the treatment of impurities generated during flue gas filtration, improving denitrification efficiency.

Description

Technical Field

[0001] This invention relates to the field of waste gas treatment technology, specifically to a denitrification system for a thermal power boiler. Background Technology

[0002] In practical industry, boiler denitrification technology is widely used. It can be found in various fields such as railways, ships, and power plants. Denitrification technology is the main method for removing nitrogen oxides from flue gas in coal-fired power plant boilers in my country. Due to the advantages of urea, such as stable supply, convenient transportation, and safe storage, using urea to replace liquid ammonia for denitrification has become a technically mature and feasible solution.

[0003] Chinese patent CN217939734U discloses a denitrification system for a gas-fired power boiler, including a dust removal tank. The dust removal tank separates dust and impurities from the flue gas, preventing them from entering the treatment tower and clogging the aeration heads. This eliminates the need for cleaning the treatment tower, improving the overall efficiency of the denitrification system and reducing maintenance costs. The aeration heads disperse the flue gas into small bubbles, ensuring sufficient contact between the flue gas and the urea solution. The spray nozzles spray the flue gas, and the urea solution-absorbing sponge sheets further treat the flue gas, resulting in more thorough denitrification and significantly improving the overall denitrification effect of the system.

[0004] However, during the use of the above-mentioned denitrification system, if the high-temperature and high-content dust or impurities in the flue gas are not treated in time after passing through the impurity removal water tank, the impurities inside the water tank may clog the filter screen, reduce the filtration effect of the flue gas, and prevent the flue gas from fully entering the treatment tower along the inlet pipe, thus reducing the denitrification efficiency. Summary of the Invention

[0005] (I) Purpose of the Invention

[0006] To address the technical problems existing in the background art, the present invention proposes a denitrification system for thermal power boilers that facilitates the removal of impurities and improves denitrification efficiency.

[0007] (II) Technical Solution

[0008] To solve the above problems, the present invention provides a denitrification system for a thermal power boiler, including an insulation box, a heater installed on the side wall of the insulation box, a denitrification box installed inside the insulation box, a second drain outlet and an air inlet pipe provided on the side wall of the insulation box, a first drain outlet provided at the bottom of the insulation box, a first discharge mechanism installed on both the second drain outlet and the first drain outlet, and a second discharge mechanism provided on the outer wall of the denitrification box and inside the insulation box.

[0009] The top of the denitrification box is detachably connected to a box cover. A feed valve is provided on one side of the top of the box cover, and an exhaust valve is provided on the other side of the top of the box cover. A first denitrification mechanism is provided in the middle of the box cover. A gas guide pipe is provided on one side of the top of the insulated box. A filter screen is provided at the air inlet end of the gas guide pipe, and the other end of the gas guide pipe is connected to the first denitrification mechanism.

[0010] Preferably, the first discharge mechanism includes a discharge pipe, which is connected to the insulation box and is located at either the first or second drain outlet. A first solenoid valve is provided on the discharge pipe near the insulation box, and a second solenoid valve is provided on the discharge pipe away from the insulation box.

[0011] Preferably, the second discharge mechanism includes an annular rotating seat installed on the outer wall of the denitrification box. The outer wall of the annular rotating seat is provided with driven teeth, which are meshed with a driving gear. The driving gear is driven to rotate by a motor installed on the top of the insulation box.

[0012] Preferably, two sets of electric telescopic rods are symmetrically arranged at the bottom of the annular rotating seat. A pusher plate is installed at the output end of the electric telescopic rod, and the left and right side walls of the pusher plate are slidably connected to the side walls of the insulation box and the denitrification box, respectively.

[0013] Preferably, the first denitrification mechanism includes a main air pipe located in the middle of the box cover. The main air pipe is driven to rotate by a driving component located at the top of the box cover. Several sets of branch air pipes are provided at the bottom of the main air pipe, and several sets of air outlets are evenly distributed on the side wall of the branch air pipes.

[0014] Preferably, a turntable is rotatably connected to the upper end of the inner wall of the main trachea, and an air guide tube is connected to the middle of the turntable. The bottom end of the air guide tube extends to the bottom of the main trachea near the bronchus.

[0015] Preferably, it also includes a second denitrification mechanism installed on the cover of the box. The second denitrification mechanism includes a first diversion pipe and a second diversion pipe. Several sets of connecting pipes are installed between the first diversion pipe and the second diversion pipe. Several sets of atomizing nozzles are installed on the first diversion pipe, the second diversion pipe and the connecting pipes. A conveying pipe is installed at one end of the first diversion pipe. A high-pressure pump is installed on the conveying pipe. The bottom end of the conveying pipe extends to the bottom of the denitrification box.

[0016] Preferably, a liquid level sensor is installed inside the insulated box.

[0017] Compared with the prior art, the above-mentioned technical solution of the present invention has the following beneficial technical effects:

[0018] 1. This invention places the heat preservation box outside the denitrification box, which facilitates the absorption and utilization of residual heat during the filtration of flue gas impurities, thus saving resources and being more environmentally friendly.

[0019] 2. The present invention uses a second discharge mechanism to facilitate the pushing of impurities floating on the water surface in the heat preservation box from the second drain port to the corresponding first discharge mechanism for discharge; the first drain port can facilitate the discharge of impurities settled at the top of the heat preservation box through the corresponding first discharge mechanism, thereby reducing the water impurity removal load and facilitating the smooth entry of flue gas into the main gas pipe through the gas guide pipe.

[0020] 3. The present invention facilitates full contact between the filtered flue gas and the urea aqueous solution through the first denitrification mechanism to complete the denitrification reaction, thereby improving work efficiency;

[0021] The present invention facilitates the spraying of urea aqueous solution at the bottom of the denitrification chamber from top to bottom through the second denitrification mechanism, so that it can fully contact the rising flue gas again to carry out a secondary denitrification reaction, thereby further improving the denitrification efficiency. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the internal structure of the insulated box of the present invention;

[0024] Figure 3 This is a schematic diagram of the denitrification box structure of the present invention;

[0025] Figure 4 This is a schematic diagram showing the connection between the second discharge mechanism and the denitrification box of the present invention;

[0026] Figure 5 This is a schematic diagram of the connection between the second denitrification mechanism and the box cover of the present invention.

[0027] Attached reference numerals: 1. Insulation box; 101. First drain outlet; 102. Second drain outlet; 103. Air inlet pipe; 2. Denitrification box; 201. Annular rotating seat; 202. Drive gear; 203. Electric telescopic rod; 204. Push plate; 3. Box cover; 301. Main air pipe; 302. Branch air pipe; 303. Air outlet; 304. Turntable; 305. Air guide pipe; 4. First branch pipe; 401. Second branch pipe; 402. Connecting pipe; 403. Atomizing nozzle; 404. Conveying pipe; 405. High-pressure pump; 5. Discharge pipe; 501. First solenoid valve; 502. Second solenoid valve. Detailed Implementation

[0028] Example 1

[0029] like Figures 1 to 4As shown, the present invention proposes a denitrification system for a thermal power boiler, including an insulation box 1, a heater provided on the side wall of the insulation box 1, a denitrification box 2 installed inside the insulation box 1, a second drain outlet 102 and an air inlet pipe 103 provided on the side wall of the insulation box 1, a first drain outlet 101 provided at the bottom of the insulation box 1, a first discharge mechanism installed on both the second drain outlet 102 and the first drain outlet 101, and a second discharge mechanism provided on the outer wall of the denitrification box 2 and inside the insulation box 1.

[0030] Furthermore, the first discharge mechanism includes a discharge pipe 5, which is connected to the insulation box 1 and is adapted to the first drain outlet 101 or the second drain outlet 102. A first solenoid valve 501 is provided on the discharge pipe 5 near the insulation box 1, and a second solenoid valve 502 is provided on the discharge pipe 5 away from the insulation box 1.

[0031] Furthermore, the second discharge mechanism includes an annular rotating seat 201 installed on the outer wall of the denitrification box 2. The annular rotating seat 201 is rotatably connected to the insulation box 1. The outer wall of the annular rotating seat 201 is provided with driven teeth, which are meshed with a driving gear 202. The driving gear 202 is driven to rotate by a motor installed on the top of the insulation box 1.

[0032] Furthermore, two sets of electric telescopic rods 203 are symmetrically arranged at the bottom of the annular rotating seat 201. A pusher plate 204 is installed at the output end of the electric telescopic rod 203. The left and right side walls of the pusher plate 204 are slidably connected to the side walls of the insulation box 1 and the denitrification box 2, respectively.

[0033] Furthermore, a liquid level sensor is installed inside the insulated box 1 to facilitate the detection of the water level inside the insulated box 1.

[0034] like Figures 1 to 3 As shown, the top of the denitrification box 2 is detachably connected to the box cover 3. A feed valve is provided on one side of the top of the box cover 3, and an exhaust valve is provided on the other side of the top of the box cover 3. A first denitrification mechanism is provided in the middle of the box cover 3. A gas guide pipe 305 is provided on one side of the top of the heat preservation box 1. A filter screen is provided at the air inlet end of the gas guide pipe 305, and the other end of the gas guide pipe 305 is connected to the first denitrification mechanism.

[0035] Furthermore, the first denitrification mechanism includes a main air pipe 301 located in the middle of the cover 3. The main air pipe 301 is driven to rotate by a driving component located at the top of the cover 3. Several sets of branch air pipes 302 are provided at the bottom of the main air pipe 301. Several sets of air outlets 303 are evenly distributed on the side wall of the branch air pipes 302. A check valve is provided at the connection between the air outlets 303 and the branch air pipes 302.

[0036] Furthermore, a turntable 304 is rotatably connected to the upper end of the inner wall of the main airway 301, and an air guide tube 305 is connected to the middle of the turntable 304. The bottom end of the air guide tube 305 extends to the bottom of the main airway 301 near the bronchus 302.

[0037] In this embodiment, an appropriate amount of water is injected into the insulation box 1 so that the water level is lower than the second drain outlet 102. Flue gas is introduced through the inlet pipe 103 and comes into contact with the water, allowing the residual heat to be absorbed by the water. The heater is then activated to reheat the water that has absorbed the heat, shortening the heating time and utilizing the residual heat of the high-temperature flue gas. Dust and impurities in the flue gas remain in the insulation box 1. The flue gas enters the main air pipe 301 along the guide pipe 305 and is ejected by several sets of outlet nozzles 303. Simultaneously, the drive unit drives the main air pipe 301 to rotate, thereby driving several sets of branch pipes 302 to rotate, allowing the flue gas to fully contact the urea solution inside the denitrification box 2 to complete the denitrification reaction. After the reaction, the flue gas moves upward and is discharged through the exhaust valve on the box cover 3. The motor drives the drive gear 202 to rotate the annular rotating seat 201, thereby... The two sets of electric telescopic rods 203 and pusher plates 204 are driven to rotate. The electric telescopic rods 203 start and drive the pusher plates 204 to move downward to a suitable height. As the pusher plates 204 rotate, the impurities floating on the water surface can be pushed from the second drain port 102 to the corresponding discharge pipe 5. Meanwhile, the sediment at the bottom of the insulation box 1 enters the corresponding discharge pipe 5 along the first drain port 101. The controller closes the first solenoid valve 501 and opens the second solenoid valve 502 to clean out the floating or sedimented impurities. After cleaning out the impurities, the second solenoid valve 502 is closed and the first solenoid valve 501 is opened to continue receiving impurities, which facilitates the cleaning of impurities and prevents the accumulation of impurities from interfering with the smooth flow of flue gas into the first denitrification mechanism along the gas guide pipe 305.

[0038] Example 2

[0039] like Figure 3 and Figure 5 As shown, the denitrification system for a thermal power boiler proposed in this invention, compared with Embodiment 1, further includes a second denitrification mechanism installed on the cover 3. The second denitrification mechanism includes a first diversion pipe 4 and a second diversion pipe 401. Several sets of connecting pipes 402 are installed between the first diversion pipe 4 and the second diversion pipe 401. Several sets of atomizing nozzles 403 are provided on the first diversion pipe 4, the second diversion pipe 401 and the connecting pipes 402. A conveying pipe 404 is installed at one end of the first diversion pipe 4. A high-pressure pump 405 is installed on the conveying pipe 404. The bottom end of the conveying pipe 404 extends to the bottom of the denitrification box 2.

[0040] In this embodiment, the urea aqueous solution at the bottom of the denitrification tank 2 is transported by the high-pressure pump 405 to the first diversion pipe 4 via the delivery pipe 404, and then to the second diversion pipe 401 via the connecting pipe 402. Finally, the urea aqueous solution is sprayed downward by several sets of atomizing nozzles 403, so that it can fully contact the flue gas after the first denitrification and improve the denitrification efficiency.

[0041] Working principle: By placing the insulation box 1 outside the denitrification box 2, the residual heat during the impurity filtration of flue gas is absorbed and utilized, saving resources and being more environmentally friendly. The annular rotating seat 201, drive gear 202, electric telescopic rod 203, and pusher plate 204 facilitate the pushing of impurities floating on the water surface in the insulation box 1 through the second drain port 102 to the corresponding discharge pipe 5 for discharge. The first drain port 101 allows impurities settled at the top of the insulation box 1 to be smoothly discharged through the corresponding discharge pipe 5, reducing the water's impurity removal load and facilitating the smooth flow of flue gas. The flue gas enters the main air pipe 301 through the guide pipe 305; the main air pipe 301, branch pipe 302, outlet 303 and turntable 304 facilitate the full contact between the filtered flue gas and the urea solution to complete the denitrification reaction, improving work efficiency; the first diversion pipe 4, the second diversion pipe 401, the connecting pipe 402, the atomizing nozzle 403, the delivery pipe 404 and the high-pressure pump 405 facilitate the spraying of the urea solution at the bottom of the denitrification box 2 from top to bottom, so that it can fully contact the rising flue gas again to carry out a secondary denitrification reaction, further improving the denitrification efficiency.

[0042] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A denitrification system for a thermal power boiler, characterized in that, The device includes an insulated box (1), a heater is provided on the side wall of the insulated box (1), a denitrification box (2) is installed inside the insulated box (1), a second drain outlet (102) and an air inlet pipe (103) are provided on the side wall of the insulated box (1), wherein an appropriate amount of water is injected into the insulated box (1) so that the residual heat is absorbed by the water, a first drain outlet (101) is provided at the bottom of the insulated box (1), a first discharge mechanism is installed on both the second drain outlet (102) and the first drain outlet (101), and a second discharge mechanism is provided on the outer wall of the denitrification box (2) and inside the insulated box (1); The second discharge mechanism includes an annular rotating seat (201) installed on the outer wall of the denitrification box (2). The outer wall of the annular rotating seat (201) is provided with driven teeth, which are meshed with a driving gear (202). The driving gear (202) is driven to rotate by a motor installed at the top of the insulation box (1). Two sets of electric telescopic rods (203) are symmetrically arranged at the bottom end of the annular rotating seat (201). A pusher plate (204) is installed at the output end of the electric telescopic rod (203). The left and right side walls of the pusher plate (204) are slidably connected to the side walls of the insulation box (1) and the denitrification box (2), respectively. The top of the denitrification box (2) is detachably connected to a box cover (3). A feed valve is provided on one side of the top of the box cover (3), and an exhaust valve is provided on the other side of the top of the box cover (3). A first denitrification mechanism is provided in the middle of the box cover (3). A gas guide pipe (305) is provided on one side of the top of the heat preservation box (1). A filter screen is provided at the air inlet end of the gas guide pipe (305), and the other end of the gas guide pipe (305) is connected to the first denitrification mechanism.

2. The denitrification system for a thermal power boiler according to claim 1, characterized in that, The first discharge mechanism includes a discharge pipe (5), which is connected to the insulation box (1) and is adapted to the first drain outlet (101) or the second drain outlet (102). A first solenoid valve (501) is provided on the discharge pipe (5) near the insulation box (1), and a second solenoid valve (502) is provided on the discharge pipe (5) away from the insulation box (1).

3. The denitrification system for a thermal power boiler according to claim 1, characterized in that, The first denitrification mechanism includes a main air pipe (301) located in the middle of the box cover (3). The main air pipe (301) is driven to rotate by a drive unit located at the top of the box cover (3). Several sets of branch pipes (302) are provided at the bottom of the main air pipe (301). Several sets of air outlets (303) are evenly distributed on the side wall of the branch pipes (302).

4. The denitrification system for a thermal power boiler according to claim 3, characterized in that, The upper end of the inner wall of the main airway (301) is rotatably connected to a turntable (304), and the middle of the turntable (304) is connected to a guide tube (305). The bottom end of the guide tube (305) extends to the bottom of the main airway (301) near the bronchus (302).

5. A denitrification system for a thermal power boiler according to claim 1, characterized in that, It also includes a second denitrification mechanism installed on the box cover (3). The second denitrification mechanism includes a first diversion pipe (4) and a second diversion pipe (401). Several sets of connecting pipes (402) are installed between the first diversion pipe (4) and the second diversion pipe (401). Several sets of atomizing nozzles (403) are installed on the first diversion pipe (4), the second diversion pipe (401) and the connecting pipes (402). A conveying pipe (404) is installed at one end of the first diversion pipe (4). A high-pressure pump (405) is installed on the conveying pipe (404). The bottom end of the conveying pipe (404) extends to the bottom of the denitrification box (2).

6. The denitrification system for a thermal power boiler according to claim 1, characterized in that, The heat preservation box (1) is equipped with a liquid level sensor.

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