Dry desulfurization reactor of circulating fluidized bed

Abstract

The utility model discloses a dry desulfurization reactor of a circulating fluidized bed, which comprises an absorption tower and a Venturi tube, the spraying system comprises a cooling recovery chamber wrapping the outer side of the feeding end of the Venturi tube, a water pipe communicated with the interior of the absorption tower, a spraying pipe communicated with the water pipe, a nozzle arranged on the spraying pipe and a cooling pipe communicated with the water pipe; the flow guide rotating mechanism comprises a flow guide plate, blades positioned on the flow guide plate, a convex block arranged on the flow guide plate, a through hole formed in the convex block, and a rotating rod which penetrates through the through hole and is fixed with the side wall of the absorption tower. The spray system arranged in the dry desulfurization reactor of the circulating fluidized bed can pre-cool the flue gas in the diffusion pipe and cool the flue gas in the absorption tower, so that the flue gas cooling effect in the whole desulfurization process is ensured; the flow guide rotating mechanism can continuously enhance friction and collision force between flue gas and particles by means of water flow impulsive force.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas desulfurization, in particular to a circulating fluidized bed dry desulfurization reactor. Background Art

[0002] Coal-fired flue gas contains a large amount of dust and SO2. Untreated coal-fired flue gas is discharged into the atmosphere, causing pollution to the atmospheric environment. At present, my country's purification of coal-fired flue gas mainly adopts wet dust removal and desulfurization and dry desulfurization methods. The common flue gas desulfurization methods are spray drying, ammonium phosphate fertilizer, furnace calcium spray tail humidification method and flue gas circulating fluidized bed method, and the most commonly used is the flue gas circulating fluidized bed method. The flue gas circulating fluidized bed desulfurization process consists of absorbent preparation, absorption tower, desulfurization ash recycling, dust collector and control system. The process generally uses dry slaked lime powder as the absorbent, and other dry powders or slurries that have the ability to absorb sulfur dioxide can also be used as absorbents. In the flue gas circulating fluidized bed method, untreated flue gas discharged from the boiler enters the bottom of the absorption tower (i.e., fluidized bed). The bottom of the absorption tower is a Venturi device. After the flue gas flows through the Venturi tube, its speed increases and it mixes with very fine absorbent powder. The gas and particles rub violently to form a fluidized bed. Under the condition of spraying water to lower the flue gas temperature, the absorbent reacts with sulfur dioxide in the flue gas to generate CaSO3 and CaSO4. After desulfurization, the flue gas carrying a large amount of solid particles is discharged from the top of the absorption tower and enters the recycling dust collector. The separated particles return to the absorption tower through the intermediate ash bin. Since the solid particles are repeatedly circulated for hundreds of times, the absorbent utilization rate is relatively high.

[0003] However, when the current absorption tower is performing flue gas desulfurization treatment, the flue gas temperature decreases slowly, and the flue gas and desulfurizer are suspended only by the acceleration of the Venturi tube. The friction and collision force between the flue gas and the particles will gradually weaken, affecting the flue gas desulfurization effect. Utility Model Content

[0004] The utility model aims to provide a circulating fluidized bed dry desulfurization reactor.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a circulating fluidized bed dry desulfurization reactor, comprising an absorption tower, and a venturi tube located at the bottom of the absorption tower, wherein the feed end of the venturi tube is located outside the absorption tower, and the discharge end of the venturi tube is located inside the absorption tower, and a spray system for cooling the flue gas temperature is arranged inside the absorption tower, wherein the spray system comprises a cooling recovery chamber wrapped around the outside of the feed end of the venturi tube, a water pipe connected to the absorption tower, a spray pipe connected to the water pipe, a nozzle arranged on the spray pipe, and a cooling pipe connected to the water pipe, wherein the cooling pipe is located in the recovery chamber;

[0006] It also includes a guide rotation mechanism, which includes a guide plate, blades located on the guide plate, a protrusion arranged on the guide plate, a through hole opened on the protrusion, and a rotating rod passing through the through hole and fixed to the side wall of the absorption tower. The rotating rod and the through hole are gap-matched so that the guide plate can rotate with the rotating rod as a fulcrum. The guide plate is an arc-shaped plate, and the lowest end of the guide plate corresponds to the recovery chamber.

[0007] Furthermore, the guide plate is divided into side A and side B with the rotating rod as a dividing interface, the length of side A is greater than the length of side B, and the bottom of side A of the guide plate corresponds to the nozzle.

[0008] Furthermore, the Venturi tube includes a contraction tube for flue gas to enter, a diffusion tube connected to the contraction tube, and a throat connected between the contraction tube and the diffusion tube. The contraction tube and the throat are located outside the absorption tower, the diffusion tube is located inside the absorption tower, and a desulfurizer inlet pipe is provided at the throat, and a blower is connected to the desulfurizer inlet pipe.

[0009] Furthermore, a water temperature drain pipe for too high a water level, a temperature sensor and a water level sensor are arranged inside the cooling recovery chamber. The water temperature drain pipe for too high a water level is provided with an electromagnetic valve 1, and the electromagnetic valve 1 is electrically connected to the temperature sensor. The water level drain pipe for too high a water level is provided with an electromagnetic valve 2, and the electromagnetic valve 2 is electrically connected to the water level sensor. The water temperature drain pipe for too high a water level is close to the bottom of the cooling recovery chamber, and the water level drain pipe for too high a water level is close to the top of the cooling recovery chamber.

[0010] It can be seen from the above technical solution that the utility model has the following beneficial effects:

[0011] The spray system of the circulating fluidized bed dry desulfurization reactor can pre-cool the flue gas in the diffusion tube and then cool the flue gas in the absorption tower to ensure the flue gas cooling effect during the entire desulfurization process; the diversion rotating mechanism can continuously enhance the friction and collision force between the flue gas and particles with the help of water flow impact to ensure the flue gas desulfurization effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0013] Figure 2 It is a schematic diagram of the structure of the integral flow-guiding rotating mechanism of the utility model.

[0014] In the figure: 1. Absorption tower; 2. Venturi tube; 2-1. Contraction tube; 2-2. Diffuser; 2-3. Throat; 2-4. Desulfurizer inlet pipe; 3-1. Cooling recovery chamber; 3-2. Water pipe; 3-3. Spray pipe; 3-4. Nozzle; 3-5. Cooling pipe; 4-1. Guide plate; 4-2. Blade; 4-3. Bump; 4-4. Through hole; 4-5. Rotating rod; 5. Blower; 6. Drain pipe for high water temperature; 7. Drain pipe for high water level; 8. Temperature sensor; 9. Water level sensor; 10. Solenoid valve 1; 11. Solenoid valve 2. DETAILED DESCRIPTION

[0015] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0016] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[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] See also Figure 1-Figure 2The utility model provides a circulating fluidized bed dry desulfurization reactor, comprising an absorption tower 1, a venturi tube 2, a spray system and a guide rotation mechanism. The venturi tube 2 is arranged at the lower end of the absorption tower 1, and the venturi tube 2 comprises a contraction tube 2-1, a diffusion tube 2-2, a throat 2-3 and a desulfurizer inlet tube 2-4. The lower end of the contraction tube 2-1 is used for the entry of coal-fired flue gas, the diffusion tube 2-2 is connected with the contraction tube, the throat 2-3 is arranged between the contraction tube and the diffusion tube, the contraction tube 2-1 and the throat 2-3 are located outside the absorption tower, the diffusion tube 2-2 is located inside the absorption tower, and the throat 2-3 is connected to the desulfurizer inlet tube 2-4, and the desulfurizer inlet tube 2-4 is connected with a blower 5. The desulfurizer adopts slaked lime powder, and the slaked lime powder enters the desulfurizer inlet tube through the blower 5 and then enters the diffusion tube 2-2 to mix with the flue gas.

[0019] The spray system includes a cooling recovery chamber 3-1, a water pipe 3-2, a spray pipe 3-3, a nozzle 3-4 and a cooling pipe 3-5. In this embodiment, the diffuser 2-2 is a funnel structure, and the cooling recovery chamber 3-1 is also a funnel structure. The cooling recovery chamber 3-1 is coaxially arranged with the diffuser 2-2, so that the cooling recovery chamber 3-1 is wrapped around the outside of the diffuser 2-2. The top of the cooling recovery chamber 3-1 is a non-sealed structure. The water inlet end of the water pipe 3-2 is located inside the absorption tower. A tee is arranged at the water inlet end of the water pipe 3-2, and the upper end of the tee is connected to the spray pipe 3-3. The upper end of the spray pipe 3-3 is connected to the nozzle 3-4, and the nozzle 3-4 is set upward. The lower end of the three-way pipe is connected to the cooling pipe 3-5. The cooling pipe 3-5 is located in the cooling recovery chamber 3-1. The cooling water enters the spray pipe 3-3 and the cooling pipe 3-5 respectively through the water pipe 3-2. The spray pipe 3-3 sprays the cooling water in the absorption tower 1 with the help of the nozzle to cool the flue gas. The cooling pipe 3-5 introduces the cooling water into the cooling recovery chamber 3-1 to cool the diffusion tube 2-2, that is, the flue gas in the diffusion tube is pre-cooled to ensure the flue gas cooling effect during the entire desulfurization process.

[0020] The guide rotating mechanism includes a guide plate 4-1, a blade 4-2, a protrusion 4-3, a through hole 4-4 and a rotating rod 4-5. The guide plate 4-1 is an arc-shaped plate, and the lowest end of the guide plate 4-1 corresponds to the recovery chamber. The blade 4-2 is arc-shaped. The material of the blade and the guide plate are both PP. The weight of the blade is less than the weight of the guide plate, and the blade is located at the upper end of the guide plate 4-1. The upper end of the guide plate is connected to the protrusion 4-3, and the protrusion is provided with a through hole 4-4. The rotating rod 4-5 passes through the through hole 4-4 and is fixedly connected to the side wall of the absorption tower, so that the guide plate 4-1 is fixed in the absorption tower. The rotating rod 4-5 and the through hole 4-4 are in clearance fit, so that the guide plate can rotate with the rotating rod as the fulcrum. The guide plate 4-1 is divided into side A and side B with the rotating rod as the dividing interface. The length of side A is greater than the length of side B. The bottom of side A of the guide plate 4-1 corresponds to the nozzle. When the nozzle sprays cooling water, the A side of the guide plate 4-1 is impacted by the water flow and rotates to one side, and the blades on the guide plate will stir and mix the flue gas and the desulfurizer powder, constantly causing intense friction between the flue gas and the particles; and because the length of the A side is greater than the length of the B side, the weight of the A side will inevitably be greater than the weight of the B side. When the A side is not impacted by the water flow, it is automatically reset by gravity, and the above work is repeated, and the friction and collision force between the flue gas and the particles are continuously enhanced with the help of the water flow to ensure the flue gas desulfurization effect. The arc-shaped guide plate will collect the water vapor in the absorption tower and recycle it to the cooling recovery chamber 3-1.

[0021] The cooling recovery chamber 3-1 is provided with a water temperature over-high drain pipe 6, a water level over-high drain pipe 7, a temperature sensor 8 and a water level sensor 9. The water temperature over-high drain pipe 6 is provided with a solenoid valve 10, which is electrically connected to the temperature sensor 8. The water level over-high drain pipe 7 is provided with a solenoid valve 2 11, which is electrically connected to the water level sensor 9. The water temperature over-high drain pipe 6 is close to the bottom of the cooling recovery chamber, and the water level over-high drain pipe 7 is close to the top of the cooling recovery chamber. When the temperature sensor 8 detects that the water temperature is too high, the diffusion tube 2-2 cannot be cooled, so the solenoid valve 10 is controlled to open to discharge the water in the cooling recovery chamber, and when the water level sensor 9 detects that the water level is too high, the solenoid valve 2 11 is controlled to open to discharge the water in the cooling recovery chamber. The pre-cooling effect of the flue gas in the diffusion tube is ensured by continuously injecting new cooling water.

[0022] When in use, the flue gas enters through the lower end of the contraction tube 2-1, the slaked lime powder enters the desulfurizer inlet tube through the blower 5, and then enters the diffusion tube 2-2 to mix with the flue gas. After the flue gas flows through the venturi tube, the speed is accelerated and mixed with the slaked lime powder. The particles and the gas and particles rub violently to form a fluidized bed. In this process, the cooling water enters the spray pipe 3-3 and the cooling pipe 3-5 respectively through the water pipe 3-2. The spray pipe 3-3 sprays the cooling water into the absorption tower 1 with the help of a nozzle to cool the flue gas. The cooling pipe 3-5 guides the cooling water into the cooling recovery chamber 3-1 to cool the diffusion tube 2-2. Cooling, and when the nozzle sprays cooling water, the A side of the guide plate 4-1 is impacted by the water flow and will rotate to one side, and the blades on the guide plate will stir and mix the flue gas and desulfurizer powder, constantly causing intense friction between the flue gas and the particles. When the A side is not impacted by the water flow, it is automatically reset by gravity and the above work is repeated, constantly using the impact of the water flow to enhance the friction and collision force between the flue gas and the particles to ensure the flue gas desulfurization effect. After desulfurization is completed, the flue gas enters the downstream bag filter through the outlet at the top of the absorption tower 1, and the separated particles return to the absorption tower through the intermediate ash bin for circulation.

[0023] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A circulating fluidized bed dry desulfurization reactor, comprising an absorption tower (1), and a venturi tube (2) located at the bottom of the absorption tower, wherein the feed end of the venturi tube (2) is located outside the absorption tower, and the discharge end of the venturi tube (2) is located inside the absorption tower, characterized in that: The absorption tower (1) is provided with a spray system for cooling the flue gas temperature, the spray system comprising a cooling recovery chamber (3-1) wrapped around the outside of the venturi tube feed end, a water pipe (3-2) connected to the absorption tower, a spray pipe (3-3) connected to the water pipe, a nozzle (3-4) provided on the spray pipe, and a cooling pipe (3-5) connected to the water pipe, wherein the cooling pipe (3-5) is located in the cooling recovery chamber (3-1); The invention also comprises a flow guide rotating mechanism, which comprises a flow guide plate (4-1), a blade (4-2) located on the flow guide plate, a protrusion (4-3) arranged on the flow guide plate, a through hole (4-4) provided on the protrusion, and a rotating rod (4-5) passing through the through hole and fixed to the side wall of the absorption tower, wherein the rotating rod (4-5) and the through hole (4-4) are loosely matched so that the flow guide plate can rotate with the rotating rod as a fulcrum, and the flow guide plate (4-1) is an arc-shaped plate, and the lowest end of the flow guide plate (4-1) corresponds to the recovery chamber.

2. The circulating fluidized bed dry desulfurization reactor according to claim 1, characterized in that: The guide plate (4-1) is divided into an A side and a B side with the rotating rod as a dividing interface, the length of the A side is greater than the length of the B side, and the bottom of the A side of the guide plate (4-1) corresponds to the nozzle.

3. The circulating fluidized bed dry desulfurization reactor according to claim 1, characterized in that: The venturi tube (2) comprises a contraction tube (2-1) for flue gas to enter, a diffusion tube (2-2) connected to the contraction tube, and a throat tube (2-3) connected between the contraction tube and the diffusion tube, wherein the contraction tube (2-1) and the throat tube (2-3) are located outside the absorption tower, the diffusion tube (2-2) is located inside the absorption tower, and a desulfurization agent inlet tube (2-4) is provided at the throat tube (2-3), and a blower (5) is connected to the desulfurization agent inlet tube (2-4).

4. The circulating fluidized bed dry desulfurization reactor according to claim 1, characterized in that: The cooling recovery chamber (3-1) is provided with a water temperature too high drain pipe (6), a water level too high drain pipe (7), a temperature sensor (8) and a water level sensor (9). The water temperature too high drain pipe (6) is provided with a solenoid valve 1 (10), and the solenoid valve 1 (10) is electrically connected to the temperature sensor (8). The water level too high drain pipe (7) is provided with a solenoid valve 2 (11), and the solenoid valve 2 (11) is electrically connected to the water level sensor (9). The water temperature too high drain pipe (6) is close to the bottom of the cooling recovery chamber, and the water level too high drain pipe (7) is close to the top of the cooling recovery chamber.

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