Collected liquid recovery device for absorption tower of thermal power plant

Abstract

The utility model discloses a liquid collection and recovery device for an absorption tower of a thermal power plant and belongs to the technical field of waste gas treatment devices. The liquid collection and recovery device for the absorption tower of the thermal power plant comprises a liquid outlet arranged at the bottom of a tower body, the liquid outlet is connected with a spraying structure arranged in the tower body through a first connecting pipe, a liquid supplementing structure for supplementing liquid to an absorbent is arranged in the tower body, the liquid supplementing structure is arranged below the spraying structure and above an air inlet, and the air inlet is connected with the liquid outlet through a second connecting pipe. And a waste heat recycling structure is arranged in the tower body and is arranged above the spraying structure. By adopting the liquid collection and recovery device for the absorption tower of the thermal power plant, the problem that the effect of continuously absorbing waste gas by an absorbent is poor due to the existing absorbent recovery device can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas treatment devices, and particularly relates to a liquid collection and recovery device for an absorption tower in a thermal power plant. Background Technique

[0002] Waste gas treatment in an absorption tower is an environmental protection measure mainly used to remove acidic gases (such as sulfur dioxide SO2), dust, and other pollutants generated during industrial production processes to reduce air pollution. Inside the absorption tower, by spraying droplets of an absorbent (usually an alkaline solution, such as lime water or sodium hydroxide solution), a chemical reaction occurs with the acidic gases in the waste gas, and sulfur dioxide will be converted into sulfite or sulfate. The absorption tower is filled with packing (such as Raschig rings), and the gas and liquid come into full contact inside the tower, increasing the reaction area and time and improving the absorption efficiency.

[0003] The absorbent sprayed inside the absorption tower needs to be recycled to improve the utilization rate of the absorbent. The existing recycling of the spraying agent inside the absorption tower generally directly uses a circulation pump to send the absorbent at the bottom of the tower body into the spray pipe for direct recycling. This utilization method causes the effect of the absorbent continuously absorbing waste gas to weaken because the absorbent has already absorbed sulfur dioxide in the waste gas, affecting the absorption effect of the waste gas. Content of the Utility Model

[0004] The purpose of the utility model is to provide a liquid collection and recovery device for an absorption tower in a thermal power plant to solve the problem that the existing absorbent recovery device results in poor continuous absorption effect of the absorbent on waste gas.

[0005] To achieve the above object, the utility model provides a liquid collection and recovery device for an absorption tower in a thermal power plant, including a liquid discharge port arranged at the bottom of the tower body. The liquid discharge port is connected to a spray structure arranged inside the tower body through a first connecting pipe. A liquid supplement structure for supplementing the absorbent is arranged inside the tower body. The liquid supplement structure is arranged below the spray structure and above the air inlet. A waste heat recovery and utilization structure is arranged inside the tower body, and the waste heat recovery and utilization structure is arranged above the spray structure.

[0006] Preferably, the liquid supplement structure includes a support seat located at the center of the tower body. The side wall of the support seat is fixedly connected to the inner wall of the tower body through a support rod. An installation rod is rotatably arranged on the support seat. A motor for driving the installation rod to rotate is arranged on the support seat. A water cavity is fixedly arranged at the bottom of the installation rod. A plurality of water pipes communicating with the water cavity are arranged on the side wall of the water cavity. Nozzles are arranged on the water pipes. The water cavity is connected to a second connecting pipe through a rotary joint. The second connecting pipe is communicated with an absorbent tank arranged outside the tower body. A first power pump for pumping the absorbent is arranged on the second connecting pipe.

[0007] Preferably, a heat insulation protective cover is arranged outside the motor.

[0008] Preferably, the spraying structure includes an arc-shaped water inlet pipe fixed to the inner wall of the tower body. The water inlet pipe is communicated with the first connecting pipe, and a circulation pump is arranged on the first connecting pipe. A plurality of parallel spraying pipes are arranged on the water inlet pipe. The spraying pipes are communicated with the water inlet pipe, and a plurality of nozzles for spraying the absorbent downward are arranged on the spraying pipes.

[0009] Preferably, a filler is arranged between the spraying structure and the liquid supplementing structure. The filler is placed on a support plate fixed to the inner wall of the tower body. A pressing plate for pressing the filler is arranged above the filler. Both the pressing plate and the support plate are of a frame structure.

[0010] Preferably, the waste heat recovery and utilization structure includes a mounting frame fixed to the inner wall of the tower body. A partition is arranged inside the mounting frame, and the partition divides the mounting frame into an upper water chamber and a lower water chamber. A lower heat exchange structure communicated with the lower water chamber is arranged at the lower part of the mounting frame, and an upper heat exchange structure communicated with the upper water chamber is arranged at the upper part of the mounting frame.

[0011] Preferably, the lower heat exchange structure includes a plurality of first branch pipes arranged in parallel. A first baffle for dividing the lower water chamber into a lower water inlet chamber and a lower water outlet chamber is arranged inside the lower water chamber. Two ends of the first branch pipes are respectively communicated with the lower water inlet chamber and the lower water outlet chamber. A first water inlet is arranged on the lower water inlet chamber, and a first drain outlet is arranged on the lower water outlet chamber. The first water inlet is communicated with a water tank arranged outside the tower body through a third connecting pipe, and the first drain outlet is connected with an external heat exchange device through a drain pipe. The water return port of the heat exchange device is communicated with the water tank through a pipeline.

[0012] Preferably, the upper heat exchange structure includes a plurality of second branch pipes arranged in parallel. A second baffle for dividing the upper water chamber into an upper water inlet chamber and an upper water outlet chamber is arranged inside the upper water chamber. Two ends of the second branch pipes are respectively communicated with the upper water inlet chamber and the upper water outlet chamber. A second water inlet is arranged on the upper water inlet chamber, and a second drain outlet is arranged on the upper water outlet chamber. The second water inlet is communicated with the third connecting pipe, and the second drain outlet is communicated with the drain pipe.

[0013] Preferably, the first branch pipes and the second branch pipes are vertically arranged, and a channel for the flue gas to pass through is formed between the first branch pipes and the second branch pipes.

[0014] Preferably, a discharge port is arranged at the bottom end of the tower body, and a valve for controlling the opening or closing of the discharge port is arranged at the discharge port.

[0015] The advantages and positive effects of a liquid collection and recovery device for an absorption tower in a thermal power plant described in this utility model are as follows: In this application, a liquid supplement structure is provided inside the tower body, and absorbent is supplemented into the tower body through the liquid supplement structure to achieve the renewal of the absorbent, which is beneficial to improving the absorption effect of the absorbent on waste gas. While supplementing the absorbent, the liquid supplement structure can preliminarily cool the waste gas; and the waste gas is stirred through a water pipe, enabling the waste gas to fully contact the absorbent sprayed from the spray pipe, thereby improving the absorption effect on the waste gas. The waste heat recovery and utilization structure provided at the upper part of the tower body can make full use of the waste heat in the waste gas, reduce the temperature of the waste gas, and improve the energy utilization rate.

[0016] The following further describes the technical solutions of this utility model in detail through the drawings and embodiments. Brief Description of the Drawings

[0017] Figure 1 It is a schematic structural diagram of an embodiment of this utility model;

[0018] Figure 2 It is a schematic cross-sectional structural diagram of an embodiment of this utility model;

[0019] Figure 3 It is a schematic spray structure diagram of an embodiment of this utility model;

[0020] Figure 4 It is a schematic bottom view structure diagram of the spray of an embodiment of this utility model;

[0021] Figure 5 It is a schematic waste heat recovery and utilization structure diagram of an embodiment of this utility model;

[0022] Figure 6 It is a schematic bottom view structure diagram of the waste heat recovery and utilization structure of an embodiment of this utility model;

[0023] Figure 7 It is a schematic cross-sectional structure diagram of the waste heat recovery and utilization structure of an embodiment of this utility model.

[0024] Reference Signs

[0025] 1, tower body; 2, air inlet; 3, exhaust port; 4, circulation pump; 5, first connecting pipe; 6, absorbent tank; 7, first power pump; 8, second connecting pipe; 9, water tank; 10, second power pump; 11, third connecting pipe; 12, liquid discharge port; 13, support rod; 14, motor; 15, water pipe; 16, pressing plate; 17, support plate; 18, spray pipe; 19, nozzle; 20, water inlet pipe; 21, installation frame; 22, partition board; 23, upper water chamber; 24, lower water chamber; 25, first branch pipe; 26, second branch pipe; 27, first baffle; 28, second baffle; 29, first water inlet; 30, first water discharge; 31, second water inlet; 32, second water discharge. Detailed implementation manners

[0026] The technical solutions of the present utility model will be further described below with reference to the accompanying drawings and embodiments.

[0027] Unless otherwise defined, the technical terms or scientific terms used in the present utility model shall have the ordinary meanings understood by those of ordinary skill in the field to which the present utility model belongs. The "first", "second" and similar terms used in the present utility model do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "comprising" or "including" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left", "right" are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0028] Embodiment

[0029] As shown in Figure 1 and Figure 2 , a liquid collection and recovery device for an absorption tower of a thermal power plant includes a liquid discharge port 12 provided at the bottom of a tower body 1. The bottom of the tower body 1 is of a conical structure to facilitate the recovery of the absorbent. The liquid discharge port 12 is connected to a spray structure provided inside the tower body 1 through a first connecting pipe 5. A discharge port is provided at the bottommost end of the conical structure of the tower body 1, and a valve is provided at the discharge port for periodically discharging the waste liquid collected at the bottom of the tower body 1. An exhaust port 3 for discharging the treated waste gas is provided at the top of the tower body 1. A demister is provided below the exhaust port 3. The demister adopts an existing structure as required and is used to remove the moisture contained in the waste gas. The waste gas from which the moisture has been removed is discharged from the tower body 1 through the exhaust port 3.

[0030] As shown in Figure 3 and Figure 4As shown in the figure. The spraying structure includes an arc-shaped water inlet pipe 20, and the water inlet pipe 20 is fixed on the inner wall of the tower body 1. The water inlet pipe 20 is communicated with the first connecting pipe 5, and the first connecting pipe 5 passes through the side wall of the tower body 1. The first connecting pipe 5 and the side wall of the tower body 1 are sealed and connected through a rubber gasket. A circulating pump 4 is arranged on the first connecting pipe 5. The circulating pump 4 is a centrifugal pump, which is used to send the absorbent at the bottom end of the tower body 1 into the water inlet pipe 20 through the first connecting pipe 5. A plurality of parallel spray pipes 18 are arranged on the water inlet pipe 20, and the spray pipes 18 are communicated with the water inlet pipe 20. One end of the spray pipe 18 is fixed on the inner wall of the tower body 1 to improve the stability of the spray pipe 18. A plurality of nozzles 19 for spraying the absorbent downward are arranged on the spray pipe 18. The absorbent is evenly sprayed downward through the nozzles 19 on the spray pipe 18, which is beneficial to the uniform distribution of the absorbent in the tower body 1, is beneficial to the full contact between the absorbent and the gas, and improves the treatment effect on the gas.

[0031] A liquid supplement structure for supplementing the absorbent is arranged inside the tower body 1. The liquid supplement structure is arranged below the spraying structure and above the air inlet 2. The waste gas enters the inside of the tower body 1 through the air inlet 2. As the absorbent contacts the waste gas, the absorbent is consumed, and the liquid supplement structure supplements the absorbent into the tower body 1 to ensure the absorption effect of the absorbent on sulfur dioxide in the waste gas.

[0032] Packing is arranged between the spraying structure and the liquid supplement structure. The packing adopts an existing packing structure according to needs. The packing is placed on the support plate 17, and the support plate 17 is fixed on the inner wall of the tower body 1. A pressing plate 16 for pressing the packing is arranged above the packing. The pressing plate 16 fixes the packing to prevent the packing from shifting during the flow of the waste gas. Both the pressing plate 16 and the support plate 17 are frame structures, which is beneficial to the flow of the waste gas.

[0033] The liquid replenishment structure includes a support base, which is located at the center of the tower body 1. The side wall of the support base is fixedly connected to the inner wall of the tower body 1 through a support rod 13. The support base is rotatably provided with a mounting rod through a bearing, and a motor 14 for driving the mounting rod to rotate is fixedly arranged on the support base. The output shaft of the motor 14 is fixedly connected to the mounting rod. An insulating protective cover is arranged outside the motor 14, and the insulating protective cover is fixed on the support base to protect the motor 14. A water cavity is fixedly arranged at the bottom of the mounting rod, and a plurality of water pipes 15 communicating with the water cavity are arranged on the side wall of the water cavity. Nozzles are fixedly arranged on the water pipes 15. The water cavity is connected to the second connecting pipe 8 through a rotary joint, and the rotary joint adopts an existing structure. The second connecting pipe 8 communicates with an absorbent tank 6 arranged outside the tower body 1. Limestone slurry is filled in the absorbent tank 6, and the limestone slurry is used as an absorbent to absorb sulfur dioxide in the waste gas. The second connecting pipe 8 passes through the tower body 1 and is hermetically connected to the tower body 1 through a rubber gasket. A first power pump 7 for pumping the absorbent is arranged on the second connecting pipe 8. The first power pump 7 is an existing centrifugal pump, which provides power for the flow of the absorbent. A liquid adding port is arranged on the absorbent tank 6 for adding limestone slurry into the absorbent tank 6.

[0034] The motor 14 drives the water cavity to rotate through the mounting rod, the water cavity drives the water pipes 15 to rotate, and the water pipes 15 drive the nozzles to rotate, so as to perform rotary spraying on the waste gas in the tower body 1, improving the spraying effect on the waste gas. While replenishing the liquid, the liquid replenishment structure is beneficial to pre-cool the waste gas and reduce the temperature of the flue gas. And during the rotation of the water pipes 15, the waste gas is stirred, so that the waste gas can uniformly enter the packing above, which is beneficial to the full contact between the waste gas and the absorbent sprayed by the spray pipe 18, improving the absorption effect on the waste gas.

[0035] A waste heat recovery and utilization structure is arranged inside the tower body 1, and the waste heat recovery and utilization structure is arranged above the spray structure. The waste heat recovery and utilization structure is used for recovering and utilizing the waste heat in the waste gas.

[0036] As Figure 5 、 Figure 6 、 Figure 7 shown. The waste heat recovery and utilization structure includes a mounting frame 21, and the mounting frame 21 is fixed on the inner wall of the tower body 1. An annular partition plate 22 is fixedly arranged inside the mounting frame 21, and the partition plate 22 divides the mounting frame 21 into a closed upper water cavity 23 and a lower water cavity 24. A lower heat exchange structure communicating with the lower water cavity 24 is arranged at the lower part of the mounting frame 21, and an upper heat exchange structure communicating with the upper water cavity 23 is arranged at the upper part of the mounting frame 21.

[0037] The lower heat exchange structure includes a number of first branch pipes 25 arranged in parallel. Inside the lower water chamber 24, there is a first baffle 27 that divides the lower water chamber 24 into a lower inlet chamber and a lower outlet chamber. Two first baffles 27 divide the lower water chamber 24 into two semi-circular chambers. The two ends of the first branch pipe 25 are respectively communicated with the lower inlet chamber and the lower outlet chamber. A first water inlet 29 is arranged on the lower inlet chamber. The first water inlet 29 is communicated with a water tank 9 arranged outside the tower body 1 through a third connecting pipe 11. The first water inlet 29 passes through the inner wall of the tower body 1 and is sealedly connected to the inner wall of the tower body 1 through a rubber sealing ring. A first drain port 30 is arranged on the lower outlet chamber. The first drain port 30 is connected to an external heat exchange device through a drain pipe. The first drain port 30 passes through the inner wall of the tower body 1 and is sealedly connected to the inner wall of the tower body 1 through a rubber sealing ring. The heat exchange device adopts an existing structure as needed. For example, an existing plate heat exchanger can be used. The water return port of the heat exchange device is communicated with the water tank 9 through a pipeline to send the heat-exchanged water back to the water tank 9.

[0038] The upper heat exchange structure includes a number of second branch pipes 26 arranged in parallel. Inside the upper water chamber 23, there is a second baffle 28 that divides the upper water chamber 23 into an upper inlet chamber and an upper outlet chamber. Two second baffles 28 divide the upper water chamber 23 into two semi-circular chambers. The two ends of the second branch pipe 26 are respectively communicated with the upper inlet chamber and the upper outlet chamber. A second water inlet 31 is arranged on the upper inlet chamber. The second water inlet 31 passes through the inner wall of the tower body 1 and is sealedly connected to the inner wall of the tower body 1 through a rubber sealing ring. A second drain port 32 is arranged on the upper outlet chamber. The second drain port 32 passes through the inner wall of the tower body 1 and is sealedly connected to the inner wall of the tower body 1 through a rubber sealing ring.

[0039] The second water inlet 31 is communicated with the third connecting pipe 11, and the second drain port 32 is communicated with the drain pipe.

[0040] The first branch pipe 25 is perpendicularly arranged to the second branch pipe 26, and a channel for the flue gas to pass through is formed between the first branch pipe 25 and the second branch pipe 26. The first branch pipe 25 and the second branch pipe 26 can adopt copper pipes, which have a relatively good heat conduction coefficient to improve the heat exchange effect. The flue gas passes through the channel between the first branch pipe 25 and the second branch pipe 26, enabling the flue gas to fully contact the first branch pipe 25 and the second branch pipe 26, which is beneficial to improving the recovery and utilization rate of the heat in the flue gas.

[0041] The water in the water tank 9 is respectively sent into the first water inlet 29 and the second water inlet 31 through the third connecting pipe 11 under the action of the second power pump 10, and then enters the upper water inlet cavity and the lower water inlet cavity. The water in the lower water inlet cavity enters the first branch pipe 25, and the water in the upper water inlet cavity enters the second branch pipe 26. The water exchanges heat with the flue gas in the first branch pipe 25 and the second branch pipe 26. The heat-exchanged water enters the lower water outlet cavity through the first branch pipe 25 and enters the upper water outlet cavity through the second branch pipe 26, and then enters the heat exchange device through the drain pipe for heat exchange. The heat-exchanged water returns to the water tank 9 through the pipeline, realizing the circulation of water.

[0042] Therefore, by adopting the liquid collection and recovery device for the absorption tower of the thermal power plant described in the present utility model, the problem that the existing absorbent recovery device causes poor effect of continuously absorbing waste gas by the absorbent can be solved.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and are not intended to limit them. Although the present utility model has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present utility model, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present utility model.

Claims

1. A liquid collection recovery device for an absorption tower in a thermal power plant, characterized in that: The tower body comprises a liquid discharge port arranged at the bottom of the tower body, the liquid discharge port is connected to a spray structure arranged inside the tower body through a first connecting pipe, a liquid replenishing structure for replenishing the absorbent is arranged inside the tower body, the liquid replenishing structure is arranged below the spraying structure, the liquid replenishing structure is arranged above the air inlet, a waste heat recovery and utilization structure is arranged inside the tower body, and the waste heat recovery and utilization structure is arranged above the spraying structure.

2. A liquid collection recovery device for an absorption tower in a thermal power plant according to claim 1, characterized in that: The liquid replenishment structure includes a support seat, which is located at the center of the tower body. The side wall of the support seat is fixedly connected to the inner wall of the tower body through a support rod. A mounting rod is rotatably arranged on the support seat. A motor for driving the mounting rod to rotate is arranged on the support seat. A water cavity is fixedly arranged at the bottom of the mounting rod. A plurality of water pipes connected to the water cavity are arranged on the side wall of the water cavity. A nozzle is arranged on the water pipe. The water cavity is connected to a second connecting pipe through a rotating joint. The second connecting pipe is connected to an absorbent box arranged outside the tower body. A first power pump for pumping absorbent is arranged on the second connecting pipe.

3. A liquid collection recovery device for an absorption tower in a thermal power plant according to claim 2, characterized in that: A heat insulation protective cover is arranged outside the motor.

4. The liquid collection recovery device for the absorption tower of a thermal power plant according to claim 1, characterized in that: The spray structure includes an arc-shaped water inlet pipe, which is fixed on the inner wall of the tower body, connected to the first connecting pipe, on which a circulating pump is provided, and on which a plurality of parallel spray pipes are provided, which are connected to the water inlet pipe, and on which a plurality of nozzles for spraying absorbent downward are provided.

5. The liquid collection recovery device for the absorption tower of a thermal power plant according to claim 1, characterized in that: A filler is arranged between the spray structure and the liquid replenishing structure. The filler is placed on a support plate, and the support plate is fixed on the inner wall of the tower body. A pressing plate for pressing the filler is arranged above the filler. Both the pressing plate and the support plate are frame structures.

6. The liquid collection recovery device for the absorption tower of a thermal power plant according to claim 1, characterized in that: The waste heat recovery and utilization structure includes an installation frame, which is fixed on the inner wall of the tower body. A partition is arranged inside the installation frame, and the partition divides the installation frame into an upper water chamber and a lower water chamber. A lower heat exchange structure connected to the lower water chamber is arranged at the lower part of the installation frame, and an upper heat exchange structure connected to the upper water chamber is arranged at the upper part of the installation frame.

7. A liquid collection recovery device for an absorption tower in a thermal power plant according to claim 6, characterized in that: The lower heat exchange structure includes a plurality of first branch pipes arranged in parallel, a first baffle is arranged inside the lower water chamber to divide the lower water chamber into a lower water inlet chamber and a lower water outlet chamber, two ends of the first branch pipe are respectively connected with the lower water inlet chamber and the lower water outlet chamber, a first water inlet is arranged on the lower water inlet chamber, a first drain is arranged on the lower water outlet chamber, the first water inlet is connected with a water tank arranged outside the tower body through a third connecting pipe, the first drain is connected with an external heat exchange device through a drain pipe, and a return water outlet of the heat exchange device is connected with the water tank through a pipeline.

8. The liquid collection recovery device for the absorption tower of a thermal power plant according to claim 7, characterized in that: The upper heat exchange structure includes a plurality of second branch pipes arranged in parallel, a second baffle is arranged inside the upper water chamber to divide the upper water chamber into an upper water inlet chamber and an upper water outlet chamber, two ends of the second branch pipe are respectively connected with the upper water inlet chamber and the upper water outlet chamber, a second water inlet is arranged on the upper water inlet chamber, a second drain outlet is arranged on the upper water outlet chamber, the second water inlet is connected with the third connecting pipe, and the second drain outlet is connected with the drain pipe.

9. A liquid collection recovery device for an absorption tower in a thermal power plant according to claim 8, characterized in that: The first branch pipe and the second branch pipe are arranged vertically, and a passage for smoke to pass through is formed between the first branch pipe and the second branch pipe.

10. A liquid collection recovery device for an absorption tower in a thermal power plant according to claim 9, characterized in that: The bottom end of the tower body is provided with a discharge port, and a valve for controlling the opening or closing of the discharge port is provided at the discharge port.

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