Spraying system for flue gas purification of power plant

Abstract

The invention discloses a spraying system for purifying flue gas of a power plant, which belongs to the field of spraying dust removal and comprises a vertically arranged tower body, a flue gas inlet pipe and a drain pipe are arranged on the lower portion of the tower body, a flue gas exhaust pipe is arranged on the upper portion of the tower body, and a purification area is arranged between the flue gas inlet pipe and the flue gas exhaust pipe in the tower body. Purification pipes with two through ends are arranged in an annular array around the vertical axis in the purification area, an independent spraying assembly is arranged on the upper portion of each purification pipe, and smoke entering the tower body from the smoke inlet pipe evenly enters the purification pipes from the lower ends of the purification pipes through the smoke distribution mechanism. According to the spraying system for flue gas purification of the power plant, the multiple independent purification pipes are arranged so that the number of the purification units put into operation can be adjusted according to requirements, and waste of energy and materials is reduced.

Description

Technical Field

[0001] This invention relates to the field of spray dust removal, specifically a spray system for purifying flue gas in power plants. Background Technology

[0002] Flue gas containing pollutants such as sulfur dioxide and dust is generated in fields such as thermal power generation. Direct emission of this gas would cause serious harm to the atmospheric environment. Therefore, it is necessary to purify the flue gas using equipment such as spray systems to achieve desulfurization and dust removal.

[0003] The working principle of a spray system is to ensure that the spray liquid comes into full contact with the flue gas flowing in from the bottom of the tower through spray components, thereby absorbing and removing pollutants. However, most existing spray systems adopt a centralized spray structure, which cannot flexibly adjust the number of purification units involved in the purification process according to changes in flue gas flow rate, pollutant concentration, etc. Under low-load conditions, the flue gas volume is significantly reduced, but the spray system still needs to operate at full load, resulting in a significant increase in spray liquid consumption and electrical energy, causing unnecessary waste of resources. Summary of the Invention

[0004] The purpose of this invention is to address the above problems by providing a spray system for purifying flue gas in power plants. By setting up multiple independent purification pipes, the number of purification units put into operation can be adjusted according to needs, thereby reducing the waste of energy and materials.

[0005] To achieve the above objectives, the present invention provides a spray system for flue gas purification in power plants. It includes a vertically arranged tower body, with an inlet pipe and an outlet pipe at the bottom and an outlet pipe at the top. A purification zone is defined within the tower body between the inlet and outlet pipes. Within the purification zone, purification pipes, extending from both ends, are arranged in a circular array around a vertical axis. Each purification pipe has an independent spray assembly at its upper part. After entering the tower body through the inlet pipe, the flue gas is evenly distributed by a smoke distribution mechanism, allowing the gas to enter individual purification pipes. When the unit is under low-load conditions, such as when the flue gas volume flow rate and pollutant concentration decrease, the number of purification pipes and corresponding spray assemblies that need to be activated can be reduced. Compared to existing centralized systems, this avoids the ineffective consumption of electrical energy for spray liquid and circulating pumps, reducing energy and material waste and significantly improving operational economy. Furthermore, each purification pipe and its spray assembly constitute an independent purification unit. When a purification unit experiences blockage, leakage, or other malfunctions, the corresponding purification pipe and spray assembly can be shut down, allowing for individual repair of the malfunctioning purification unit without stopping the entire spray system, thus improving system availability and maintenance efficiency.

[0006] Furthermore, the smoke distribution mechanism includes guide plates and gathering plates spaced apart vertically. The guide plates are located above the gathering plates, and both the guide plates and gathering plates are arc-shaped, with their centers located on the vertical axis of the annular array of purification pipes. The center of the guide plates faces upward, and through holes corresponding to and communicating with the lower parts of the purification pipes are opened on the guide plates. The center of the gathering plates faces downward, and air guide holes are opened in the middle of the gathering plates. Both the guide plates and the gathering plates are fixedly connected to the inner wall of the tower body. The flue gas entering the tower body first converges towards its center under the guidance of the arc-shaped gathering plates and passes through the central air guide holes, thereby completing the rectification. Subsequently, the flue gas flows upward and is diverted to the corresponding purification pipes through the through holes on the guide plates, thereby ensuring the uniformity of the flue gas flow at the lower inlet of each purification pipe, avoiding overload or underload, and ensuring the purification effect.

[0007] Furthermore, a drain outlet is provided between the edge of the agglomerating plate and the inner wall of the tower body. This allows the spray liquid on the agglomerating plate to flow quickly to the drain pipe below, preventing liquid accumulation on the agglomerating plate.

[0008] Furthermore, each purification pipe is fixedly equipped with a baffle plate on its lower wall, and a flue gas hole is provided through the baffle plate. An opening and closing device is installed at each flue gas hole. By operating the independent opening and closing device of each purification pipe, the purification pipe can be opened or closed individually. When the opening and closing device is closed, the corresponding purification pipe is isolated from other purification pipes. This allows the system to flexibly control the number of purification pipes in operation according to actual needs, and also facilitates maintenance of the purification unit containing that purification pipe.

[0009] Furthermore, the flue gas vent is coaxially arranged with the purification pipe, and the upper and lower surfaces of the partition are configured as guide surfaces inclined towards the flue gas vent, so as to guide the droplets generated during the spraying process and the flue gas entering the purification pipe to the flue gas vent.

[0010] Furthermore, the tower body is equipped with a diversion tank coaxial with the axis of the annular array of purification tubes. The diversion tank is connected to each purification tube via multiple independent air guide pipes. The inlet of each air guide pipe is located below the partition of the corresponding purification tube, and the outlet is located at the lower part of the diversion tank. The diversion tank is also connected to each purification tube via multiple independent diversion pipes. The inlet of each diversion pipe is located at the upper part of the diversion tank, and the outlet is connected to the purification tube. Valves are installed on the air guide pipes and diversion pipes. For any target purification tube, when it needs to be closed, the opening and closing device at its partition and the valve on its diversion pipe are closed, while the valve on its air guide pipe is opened. For the remaining purification tubes that need to remain open, the opening and closing device at its partition and the valve on its diversion pipe are opened, while the valve on its air guide pipe is closed. In this way, the flue gas flowing towards the closed purification pipe is guided into the distribution tank through its guide pipe. After mixing in the tank, it is then evenly redistributed to the open purification pipes through the distribution pipes corresponding to all the open purification pipes. Thus, when one or more purification pipes are closed, the system can actively guide the flue gas that would otherwise enter that pipe to the distribution tank. After mixing in the distribution tank, the flue gas is output through the distribution pipes of the remaining open purification pipes at equal pressure. This avoids severe flow unevenness caused by the flue gas only flowing into the purification pipe adjacent to the closed one due to the principle of proximity, ensuring that the flue gas flow distributed to the purification pipes in all operating states remains highly uniform, thereby maintaining the stability of the overall purification efficiency of the system.

[0011] Furthermore, the top wall of the diversion tank is arc-shaped, with its center facing downwards and located on the vertical axis of the annular array of purification pipes. When flue gas flows into the diversion tank from multiple lower guide pipes, the arc-shaped top wall with its center facing downwards provides a smooth guiding surface for the rising airflow, ensuring uniform redistribution through the diversion pipes.

[0012] Furthermore, each purification pipe is provided with an inspection port on the side wall of the tower body, and the inspection port is equipped with an openable and closable inspection door. This allows for maintenance and repair of individual purification units without requiring a complete system shutdown, greatly improving the flexibility and efficiency of maintenance operations.

[0013] Furthermore, each purification pipe inside the tower is equipped with a vertically movable baffle, with each baffle corresponding to a purification pipe. By controlling the raising and lowering of the corresponding baffle, the flue gas outlet at the top of the purification pipe below it can be physically opened or closed. When the lower part of a purification pipe is closed, its corresponding baffle can be completely lowered to close its upper outlet, effectively preventing the purified flue gas discharged from other operating purification pipes from flowing back or short-circuiting.

[0014] Furthermore, the top wall of the tower body is provided with a storage groove for accommodating the baffles. The lower surface of each baffle is set as an inclined surface, with one side of the inclined surface facing the exhaust pipe. When the baffle is fully raised, it is located in the storage groove, which reduces the eddies and vibrations caused by the purified flue gas flowing into the gap between the baffle and the tower wall. At the same time, the inclined surface of the lower surface of the baffle guides the purified flue gas to the exhaust pipe, thereby improving the exhaust efficiency.

[0015] The beneficial effects of this invention are as follows: The number of purification units in operation can be flexibly adjusted according to the flow rate and concentration of the inlet flue gas, achieving precise matching between processing capacity and load. Under low-load conditions, unnecessary operation of purification units can be reduced, thereby significantly reducing the consumption of spray liquid and the operating energy consumption of equipment such as circulating pumps, avoiding waste of energy and materials. Each purification pipe and its matching spray assembly constitute a completely independent purification unit. When any unit experiences a fault such as blockage or leakage, that unit can be shut down independently and isolated from the system, allowing for maintenance without affecting the normal operation of other units. This improves the overall availability and operational efficiency of the system. Attached Figure Description

[0016] Figure 1 This is a side view of the internal structure of the tower.

[0017] Figure 2 This is a schematic diagram of the purification pipe layout from a top-down view.

[0018] The text labels in the diagram represent: 1. Tower body; 2. Smoke inlet pipe; 3. Drainage pipe; 4. Smoke exhaust pipe; 5. Purification pipe; 6. Spray assembly; 7. Guide plate; 8. Gathering plate; 9. Through hole; 10. Air guide hole; 11. Liquid outlet; 12. Baffle plate; 13. Opening and closing device; 14. Diversion tank; 15. Air guide pipe; 16. Diversion pipe; 17. Inspection door; 18. Baffle; 19. Storage tank; 20. Connecting pipe; 21. Lifting drive device. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of the present invention in any way.

[0020] Example 1, such as Figures 1-2As shown, the specific structure of this embodiment is as follows: a spray system for purifying flue gas in a power plant, comprising a vertically arranged tower body 1, with an inlet pipe 2 and a drain pipe 3 at the lower part of the tower body 1, and an exhaust pipe 4 at the upper part of the tower body 1. A purification zone is set within the tower body 1 between the inlet pipe 2 and the exhaust pipe 4. Purification pipes 5, with both ends extending through each other, are arranged in a circular array around a vertical axis within the purification zone. The exhaust pipe 4 is coaxial with the array axis of the purification pipes 5. The cross-section of the channels within the purification pipes 5 is preferably circular to reduce local eddies, etc. Each purification pipe 5 has an independent spray assembly 6 at its upper part. Each spray assembly 6 includes an annular main pipe and multiple atomizing nozzles connected to it. The annular main pipe is connected to an external liquid supply main pipe but is equipped with an independent control valve, allowing for independent start / stop and flow rate adjustment of the spray liquid for that purification pipe 5. A sieve plate can be installed at the lower part of the purification pipe 5 as needed, with packing material placed on the sieve plate. Cooling channels can be provided on the side wall of the purification pipe 5, and coolant flows in the cooling channels to reduce the temperature inside the purification pipe 5.

[0021] A smoke distribution mechanism is provided inside the tower body between the purification pipe 5 and the smoke inlet pipe 2. The smoke distribution mechanism includes guide plates 7 and gathering plates 8 arranged at intervals. The edges of the guide plates 7 and gathering plates 8 are fixedly connected to the inner wall of the tower body through welding or other processes. A drain port 11 is provided between the edge of the gathering plate 8 and the inner wall of the tower body 1. Multiple drain ports 11 can be arranged around the axis of the annular array of purification pipes 5. The guide plate 7 is located above the gathering plate 8. Both the guide plate 7 and the gathering plate 8 are arc-shaped, and their centers are located on the vertical axis of the annular array of purification pipes 5. The arc center of the guide plate 7 faces upward, and the guide plate 7 has through holes 9 that correspond one-to-one with and communicate with the lower part of the purification pipes 5. The center of the gathering plate 8 faces downward, and the gathering plate 8 has an air guide hole 10 in the middle. A connecting pipe 20 is provided on the upper surface of the gathering plate 8 outside the air guide hole 10. The upper end of the connecting pipe 20 is fixedly connected to the guide plate 7. A through hole is provided on the upper part of the side wall of the connecting pipe 20. The position and number of the through hole are adapted to the purification pipes 5. The connecting pipe 20 is used to promote the accumulation of flue gas. The outlet of the flue gas inlet pipe 2 is located below the air guide hole 10.

[0022] A baffle plate 12 is welded and fixedly installed on the lower wall of each purification pipe 5. A circular flue gas hole coaxial with the purification pipe 5 is opened in the center of the baffle plate 12. An opening and closing device 13 is installed at the flue gas hole. The opening and closing device 13 can be a pneumatic butterfly valve, a baffle plate driven by a cylinder, etc. The opening and closing device 13 is used to open and close the flue gas passage of the purification pipe 5. The upper and lower surfaces of the baffle plate 12 are both machined into guide surfaces inclined towards the flue gas hole, and the lower side of the guide surface is located near the end of the flue gas hole.

[0023] Above each purification pipe 5, a baffle 18 is installed that can move up and down along a vertical guide rail. The baffle 18 is driven by a lifting drive device 21 at the top of the tower body 1. The lifting drive device 21 can be a hydraulic cylinder or the like. The baffles 18 are set one-to-one with the purification pipes 5. On the top wall of the tower body 1, a receiving groove 19 is provided corresponding to the upper limit position of each baffle 18. When the baffle 18 is raised to the highest point, its main body can be completely embedded in this groove. The lower surface of each baffle 18 is processed into a slope, and the lower side of the slope faces the exhaust pipe 4 in the center of the tower body.

[0024] The tower body 1 has a cylindrical diversion tank 14 coaxial with the array of purification pipes 5 at its center, and the lower end of the diversion tank 14 is fixed to the guide plate 7. The middle part of the side wall of the diversion tank 14 is designed as an inwardly concave annular narrowing structure to promote flue gas mixing. Its top wall is an arc-shaped dome with the center facing downward and coincides with the array axis of the purification pipes 5.

[0025] Each purification pipe 5 is connected to the distribution tank 14 via two independent pipes. The inlet of one end of the guide pipe 15 is located on the side wall of the corresponding purification pipe 5, below the partition 12; the outlet of the other end connects to the lower part of the distribution tank 14. The guide pipe 15 is equipped with an electric or pneumatic valve. The outlet of one end of the distribution pipe 16 is located on the side wall of the corresponding purification pipe 5; the inlet of the other end connects to the upper part of the distribution tank 14. The distribution pipe 16 is also equipped with an electric or pneumatic valve. That is, the outlet of the distribution pipe 16 and the inlet of the guide pipe 15 are on the same side and located on the upper and lower sides of the partition 12, respectively. The inlet of the distribution pipe 16 and the outlet of the guide pipe 15 are on the same side. A fan or similar device is installed inside the distribution pipe 16 to guide the flow of flue gas. A one-way valve can also be installed inside the distribution pipe 16 to prevent flue gas from the purification pipe 5 from entering the distribution tank 14 through the distribution pipe 16.

[0026] On the side wall of the tower body 1, an inspection port is provided corresponding to the position of each purification pipe 5, and an inspection door 17 with a sealing ring is hinged to the outside of each inspection port.

[0027] Specific working process: During normal full-load operation, flue gas enters tower 1 from inlet pipe 2, is collected by gathering plate 8, and moves upward through guide hole 10. The flue gas then encounters guide plate 7, is forcibly dispersed, and evenly enters the lower end of corresponding purification pipe 5 through through holes 9. All opening and closing devices 13 of purification pipe 5 are activated, and its spray assembly 6 is engaged. As the flue gas rises within the purification pipe 5, it comes into contact with the spray liquid sprayed from top to bottom, completing desulfurization and dust removal. The purified flue gas flows out from the upper end of each purification pipe 5, collects at the top of tower 1, and is discharged through exhaust pipe 4, while the condensed droplets flow away through drain port 11. At this time, all valves on guide pipe 15 are closed, all valves on diversion pipe 16 are also closed, and diversion tank 14 does not participate in operation. All baffles are in the raised and collected state within the trough 19, not affecting flue gas convergence.

[0028] When it is necessary to shut down a specific purification pipe 5, this embodiment will use the shutdown of purification pipe No. 1 as an example. First, close the control valve of the spray assembly 6 corresponding to purification pipe No. 1. Next, close the opening and closing device 13 on the partition 12 inside purification pipe No. 1 to cut off the main flue gas passage. At the same time, open the valve on the air guide pipe 15 connected to purification pipe No. 1 and close the valve on the diversion pipe 16 connected to it. Keep the opening and closing devices 13 of all other purification pipes open, and ensure that their spray assemblies 6 operate normally. At the same time, ensure that the valve of the air guide pipe 15 connected to the operating purification pipe is closed, while the valve of the diversion pipe 16 is open.

[0029] The flue gas from the inlet pipe 2, upon reaching the closed inlet of the first purification pipe, is prevented from entering due to the closed opening and closing device 13. This portion of the flue gas pressure increases and is instead drawn into the lower part of the distribution tank 14 through the open duct 15. Inside the distribution tank 14, particularly through its central recess, the flue gas is thoroughly mixed. Subsequently, the mixed flue gas is evenly redistributed from the upper part of the distribution tank 14 through all the open distribution pipes 16 and injected into each operating purification pipe 5. At this time, the baffle 18 corresponding to the first purification pipe descends, tightly covering the upper outlet of the first purification pipe to prevent airflow from other pipes from entering. Figure 1 In the diagram, solid arrows indicate the flue gas flow path during normal full-load operation of the system; dashed arrows indicate the alternative flow path of the flue gas originally planned to enter a purification pipe when a certain purification pipe (such as purification pipe No. 1) is closed.

[0030] At this point, the inspection door 17 corresponding to the No. 1 purification pipe can be safely opened for internal maintenance, while the rest of the system continues to operate.

[0031] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0032] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only for the purpose of helping to understand the method and core ideas of the present invention. The above descriptions are only preferred embodiments of the present invention. It should be noted that due to the limitations of textual expression, there are objectively infinite specific structures. For those skilled in the art, several improvements, modifications, or changes can be made without departing from the principles of the present invention, and the above technical features can also be combined in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. A spray system for purifying flue gas in a power plant, comprising a vertically arranged tower body (1), wherein a flue gas inlet pipe (2) and a drain pipe (3) are provided at the lower part of the tower body (1), and a flue gas exhaust pipe (4) is provided at the upper part of the tower body (1), wherein a purification zone is provided within the tower body (1) between the flue gas inlet pipe (2) and the flue gas exhaust pipe (4), characterized in that, The purification zone is arranged in a ring array around the vertical axis with purification pipes (5) that are connected at both ends. Each purification pipe (5) is equipped with an independent spray assembly (6) at the top. The flue gas entering the tower body (1) from the smoke inlet pipe (2) is evenly distributed into the purification pipe (5) from the bottom end of the purification pipe (5) by the smoke distribution mechanism.

2. The spray system for purifying flue gas in power plants according to claim 1, characterized in that, The smoke distribution mechanism includes a guide plate (7) and a gathering plate (8) arranged at intervals. The guide plate (7) is located above the gathering plate (8). Both the guide plate (7) and the gathering plate (8) are arc-shaped, and their centers are located on the vertical axis of the annular array of purification pipes (5). The center of the guide plate (7) faces upward, and the guide plate (7) has through holes (9) that correspond one-to-one with and communicate with the lower part of the purification pipes (5). The center of the gathering plate (8) faces downward, and the gathering plate (8) has an air guide hole (10) in the middle.

3. A spray system for purifying flue gas in power plants according to claim 2, characterized in that, A drain port (11) is provided between the edge of the agglomeration plate (8) and the inner wall of the tower body (1).

4. A spray system for purifying flue gas in power plants according to claim 1, characterized in that, Each purification pipe (5) has a partition (12) fixedly installed on the lower pipe wall. The partition (12) has a flue gas hole, and the flue gas hole is equipped with an opening and closing device (13).

5. A spray system for purifying flue gas in power plants according to claim 4, characterized in that, The flue gas vent is coaxially arranged with the purification pipe (5), and the lower surface of the partition plate (12) is set as a guide surface inclined towards the flue gas vent.

6. A spray system for purifying flue gas in power plants according to claim 4, characterized in that, The tower body (1) is equipped with a diversion tank (14) coaxial with the annular array axis of the purification pipe (5); the diversion tank (14) is connected to each purification pipe (5) through multiple independent air guide pipes (15), the air inlet of each air guide pipe (15) is located below the partition (12) of the corresponding purification pipe (5), and the air outlet is located at the lower part of the diversion tank (14); the diversion tank (14) is also connected to each purification pipe (5) through multiple independent diversion pipes (16), the air inlet of each diversion pipe (16) is located at the upper part of the diversion tank (14), and the air outlet is connected to the purification pipe (5); valves are respectively provided on the air guide pipes (15) and the diversion pipes (16).

7. A spray system for purifying flue gas in power plants according to claim 6, characterized in that, The top wall of the diversion tank (14) is set in an arc shape, with the center of the top wall of the diversion tank (14) facing downwards and located on the vertical axis of the annular array of purification pipes (5).

8. A spray system for purifying flue gas in power plants according to claim 4, characterized in that, Each purification pipe (5) is provided with an inspection port on the side wall of the tower body (1), and an openable and closable inspection door (17) is provided at the inspection port.

9. A spray system for purifying flue gas in power plants according to claim 8, characterized in that, Inside the tower body (1), above each purification pipe (5), there is a baffle (18) that can move vertically, and the baffle (18) is set one-to-one with the purification pipe (5).

10. A spray system for purifying flue gas in power plants according to claim 9, characterized in that, The top wall of the tower body (1) is provided with a storage groove (19) for storing baffles (18), and the lower surface of each baffle is set as an inclined surface, with one side of the inclined surface facing the exhaust pipe (4).

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