Water-soluble gas recovery tower

Abstract

The utility model discloses a water-soluble gas recovery tower which comprises a buffer tank, a first-stage absorption tower, a second-stage absorption tower, a third-stage absorption tower and an induced draft fan, the upper end of the buffer tank is communicated with the lower end of the first-stage absorption tower, the upper end of the second-stage absorption tower is communicated with the lower end of the third-stage absorption tower, and the upper end of the third-stage absorption tower is connected with an inlet of the induced draft fan. A first spraying mechanism and a heat exchanger are arranged in the first-stage absorption tower, an air inlet pipe is connected to the periphery of the first-stage absorption tower, and the connecting position of the air inlet pipe and the first-stage absorption tower is lower than the first spraying mechanism and higher than the heat exchanger, and a second spraying mechanism and a third spraying mechanism are arranged on the upper portion of the second-stage absorption tower and the upper portion of the third-stage absorption tower respectively. And an air supply pipe and an overflow pipe are connected between the buffer tank and the secondary absorption tower. The absorption liquid can be used for multiple times, and the utilization rate of the absorption liquid is increased.

Description

Technical Field

[0001] This utility model relates to the field of gas recovery technology, and more specifically, to a water-soluble gas recovery tower. Background Technology

[0002] With the rapid advancement of industrialization, numerous industries such as chemical, pharmaceutical, and food processing generate large quantities of various gases during their production processes, including many water-soluble gases such as ammonia, hydrogen chloride, and sulfur dioxide. If these water-soluble gases are not properly recovered and treated, they can combine with moisture in the atmosphere to form acid rain and other severe weather conditions, causing serious corrosion and damage to soil, water bodies, vegetation, and other ecosystems, threatening biodiversity. Traditional absorption towers, while widely used, discharge the absorbent liquid after it comes into contact with the gas. This absorbent liquid is used only once and then discharged, failing to achieve full utilization. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a water-soluble gas recovery tower.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] This utility model discloses a water-soluble gas recovery tower, including a buffer tank, a primary absorption tower, a secondary absorption tower, a tertiary absorption tower, and an induced draft fan. The upper end of the buffer tank is connected to the lower end of the primary absorption tower, the upper end of the secondary absorption tower is connected to the lower end of the tertiary absorption tower, and the upper end of the tertiary absorption tower is connected to the inlet of the induced draft fan. The primary absorption tower is equipped with a spray mechanism and a heat exchanger. An air inlet pipe is connected to the outer periphery of the primary absorption tower. The connection between the air inlet pipe and the primary absorption tower is lower than the spray mechanism and higher than the heat exchanger. The upper parts of the secondary and tertiary absorption towers are respectively equipped with a second and a third spray mechanism. A gas supply pipe and an overflow pipe are connected between the buffer tank and the secondary absorption tower. The connection between the gas supply pipe and the secondary absorption tower is higher than the connection between the overflow pipe and the secondary absorption tower, and the connection between the gas supply pipe and the buffer tank is higher than the connection between the overflow pipe and the buffer tank. It also includes a discharge circulation pump. The inlet of the discharge circulation pump is connected to the buffer tank through a pipe, and the outlet of the discharge circulation pump is connected to the second and first spray mechanisms through pipes.

[0006] Furthermore, it also includes a discharge port, and the outlet of the discharge circulation pump is connected to the discharge port through a pipeline.

[0007] Furthermore, the two ends of the heat exchanger are connected to the circulating water inlet main pipe and the circulating water outlet main pipe, respectively, and the height of the circulating water inlet main pipe is lower than that of the circulating water outlet main pipe.

[0008] Furthermore, a demister is installed at the upper end of the three-stage absorption tower, and the demister is located above the spraying mechanism.

[0009] Furthermore, it also includes an absorbent system, which is connected to the spray mechanism three via a pipeline. The absorbent system supplies absorbent to the spray mechanism three. An absorbent inlet flow regulating valve is installed on the pipeline connecting the absorbent system and the spray mechanism three. The inlet of the induced draft fan is connected to the upper end of the three-stage absorption tower via a pipeline. A concentration analyzer is installed on the pipeline connecting the induced draft fan and the three-stage absorption tower. The absorbent inlet flow regulating valve is electrically connected to the concentration analyzer.

[0010] Furthermore, a level gauge is installed on the buffer tank, and a discharge flow regulating valve is installed on the pipeline connecting the discharge circulation pump and the discharge port. The discharge flow regulating valve is electrically connected to the level gauge.

[0011] Furthermore, both the secondary and tertiary absorption towers are equipped with packing material. The packing material in the secondary absorption tower is located below the second spraying mechanism, and the packing material in the tertiary absorption tower is located below the third spraying mechanism.

[0012] The beneficial effects of this utility model are: the absorbent liquid in the secondary absorption tower and the tertiary absorption tower is temporarily stored at the bottom of the secondary absorption tower and then overflows into the buffer tank. Part of the absorbent liquid in the buffer tank can be reused in the spray mechanism one and the spray mechanism two. The absorbent liquid is recycled, so that the absorbent liquid is fully utilized. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a water-soluble gas recovery tower in this embodiment;

[0014] Figure 2 This is a partial structural schematic diagram of the water-soluble gas recovery tower in this embodiment.

[0015] Attached reference numerals: 1. Buffer tank; 2. Primary absorption tower; 3. Secondary absorption tower; 4. Tertiary absorption tower; 5. Demister; 6. Exhaust fan; 7. Discharge circulation pump; 8. Spray mechanism three; 9. Spray mechanism two; 10. Spray mechanism one; 11. Absorbent liquid system; 12. Gas phase inlet; 13. Discharge port; 14. Circulating water inlet main pipe; 15. Circulating water outlet main pipe; 16. U-shaped water seal; 17. Inlet flow regulating valve; 18. Thermometer; 19. Level gauge; 20. Discharge flow regulating valve; 21. Gas phase inlet pipe pressure gauge; 22. Variable frequency controller; 23. Concentration analyzer; 24. Absorbent liquid inlet flow regulating valve; 25. Flow meter; 26. Exhaust fan inlet pressure gauge; 27. Gas supply pipe; 28. Overflow pipe. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] like Figures 1-2 As shown, a water-soluble gas recovery tower includes a buffer tank 1, a primary absorption tower 2, a secondary absorption tower 3, a tertiary absorption tower 4, a demister 5, an induced draft fan 6, a discharge circulation pump 7, and an absorption liquid system 11. The upper end of the buffer tank 1 is connected to the lower end of the primary absorption tower 2, and the upper end of the secondary absorption tower 3 is connected to the lower end of the primary absorption tower 2. The secondary absorption tower 3 is located above the primary absorption tower 2 and is separated from the primary absorption tower 2 and is not connected to it.

[0018] A heat exchanger is installed inside the primary absorption tower 2, and a spray mechanism 10 is installed above the heat exchanger. The heat exchanger is a shell-and-tube type, arranged along the length of the primary absorption tower 2. Both ends of the heat exchanger are connected to a circulating water inlet main pipe 14 and a circulating water outlet main pipe 15, respectively. The height of the circulating water inlet main pipe 14 is lower than that of the circulating water outlet main pipe 15. An inlet flow regulating valve 17 is installed on the circulating water inlet main pipe 14, and a thermometer 18 is installed on the buffer tank 1. The inlet flow regulating valve 17 is electrically connected to the thermometer 18. The temperature of the liquid in the buffer tank 1 is detected by the thermometer 18. When the liquid temperature is higher than the set value, the inlet flow regulating valve 17 increases its opening, increasing the amount of liquid entering the primary absorption tower 2 and ensuring heat exchange efficiency. An air inlet pipe is connected to the outer periphery of the primary absorption tower 2. The connection between the air inlet pipe and the primary absorption tower 2 is located between the spray mechanism 10 and the primary absorption tower 2. The other end of the air inlet pipe is connected to the gas phase inlet 12. The gas to be treated at the gas inlet 12 enters the primary absorption tower 2 through the inlet pipe, where the water-soluble gases in the gas are absorbed by the absorbent discharged from the spray mechanism 10. Simultaneously, the gas passes through the primary absorption tower 2 and enters the buffer tank 1, where the primary absorption tower 2 exchanges heat with the gas, lowering its temperature and facilitating treatment. The gas in the buffer tank 1 enters the lower part of the secondary absorption tower 3 through the gas supply pipe 27.

[0019] Spray mechanism 3 (8) and spray mechanism 2 (9) are installed in the secondary absorption tower 3 and tertiary absorption tower 4, respectively. Packing material is installed below spray mechanisms 3 (8) and 2 (9) in both towers. The packing material provides sufficient contact surface for the gas and liquid phases, and its height is 1800-2100 mm. A gas supply pipe 27 and an overflow pipe 28 connect the buffer tank 1 and the secondary absorption tower 3. The connection point of the gas supply pipe 27 to the secondary absorption tower 3 is higher than the connection point of the overflow pipe 28 to the secondary absorption tower 3, and the connection point of the gas supply pipe 27 to the buffer tank 1 is higher than the connection point of the overflow pipe 28 to the buffer tank 1. The end of the gas supply pipe 27 connected to the secondary absorption tower 3 is inclined upwards at 3° to prevent condensate from clogging the pipe. A U-shaped water seal 16 is installed near the connection point of the overflow pipe 28 to the buffer tank 1. The U-shaped water seal 16 prevents gas from passing through the overflow pipe 28, thus preventing cross-contamination between the buffer tank 1 and the secondary absorption tower 3.

[0020] The gas passes through the secondary absorption tower 3 and the tertiary absorption tower 4, and is then guided and discharged by the induced draft fan 6. While in the secondary absorption tower 3 and the tertiary absorption tower 4, the gas is absorbed by the water-soluble gases by the absorption liquid discharged through the spray mechanism 3 8 and the spray mechanism 2 9. This liquid falls into the bottom of the secondary absorption tower 3 for temporary storage, and overflows into the buffer tank 1 through the overflow pipe 28 after reaching a certain amount.

[0021] A demister 5 is installed inside the three-stage absorption tower 4, above the spray mechanism 8. The gas passes through the demister 5 to remove condensation and reduce entrained liquid droplets.

[0022] The inlet of the induced draft fan 6 is connected to the upper end of the three-stage absorption tower 4, and the outlet of the induced draft fan 6 is connected to the atmosphere. A concentration analyzer 23 and an inlet pressure gauge 26 are installed on the pipe connecting the induced draft fan 6 and the three-stage absorption tower 4. The absorbent system 11 is connected to the spray mechanism 8 via a pipe, and the absorbent system 11 provides new absorbent to the spray mechanism 8 through the pipe. An absorbent inlet flow regulating valve 24 and a flow meter 25 are installed on the pipe connecting the absorbent system 11 and the spray mechanism 8. The absorbent inlet flow regulating valve 24 is electrically connected to the concentration analyzer 23. The concentration analyzer 23 detects the concentration of water-soluble gases in the discharged gas. When the concentration is higher than a set value, the absorbent inlet flow regulating valve 24 is opened wider, increasing the amount of new absorbent entering the spray mechanism 8 to absorb more water-soluble gases and reduce the concentration of water-soluble gases in the discharged gas.

[0023] The inlet of the discharge circulation pump 7 is connected to the buffer tank 1, and the outlet of the discharge circulation pump 7 is connected to the spray mechanism 2 9, the spray mechanism 10, and the discharge port 13 via pipelines. Part of the absorbent in the buffer tank 1 is pumped by the discharge circulation pump 7 into the spray mechanism 2 9 and the spray mechanism 10 for continued absorption of water-soluble gases, while the remaining part is pumped out from the discharge port 13 by the discharge circulation pump 7. Simultaneously, new absorbent is added to the absorbent system 11 to maintain a balance in the total amount of absorbent. The primary absorption tower 2 and the secondary absorption tower 3 use the old absorbent for preliminary absorption, while the tertiary absorption tower 4 uses new absorbent for final absorption. This multiple absorption process ensures full utilization of the absorbent and guarantees sufficient absorption of water-soluble gases.

[0024] A discharge flow regulating valve 20 is installed on the pipeline connecting the discharge circulation pump 7 and the discharge port 13. A level gauge 19 is installed on the buffer tank 1. The discharge flow regulating valve 20 and the level gauge 19 are electrically connected. The level gauge 19 is used to detect the amount of absorbent liquid in the buffer tank 1. When the amount of absorbent liquid exceeds the set value, the opening of the discharge flow regulating valve 20 is increased, so that the amount of absorbent liquid discharged from the discharge port 13 increases, thereby keeping the total amount of absorbent liquid in the tower balanced.

[0025] The induced draft fan 6 is controlled by a frequency converter 22. A gas inlet pipe pressure gauge 21 is installed on the pipe connecting the gas inlet 12 and the primary absorption tower 2. The frequency converter 22 is associated with the gas inlet pipe pressure gauge 21. When the gas inlet pipe pressure gauge 21 detects that the pressure rise exceeds the preset value, the frequency converter 22 controls the induced draft fan 6 to increase its operating frequency and increase the discharge to ensure pressure stability.

[0026] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A water-soluble gas recovery tower, characterized in that, The system includes a buffer tank (1), a primary absorption tower (2), a secondary absorption tower (3), a tertiary absorption tower (4), and an induced draft fan (6). The upper end of the buffer tank (1) is connected to the lower end of the primary absorption tower (2), the upper end of the secondary absorption tower (3) is connected to the lower end of the tertiary absorption tower (4), and the upper end of the tertiary absorption tower (4) is connected to the inlet of the induced draft fan (6). The primary absorption tower (2) is equipped with a spray mechanism (10) and a heat exchanger. An air inlet pipe is connected to the outer periphery of the primary absorption tower (2). The connection between the air inlet pipe and the primary absorption tower (2) is lower than the spray mechanism (10) and higher than the heat exchanger. The upper parts of the secondary absorption tower (3) and the tertiary absorption tower (4) are respectively... The system is equipped with a second spray mechanism (9) and a third spray mechanism (8). A gas supply pipe (27) and an overflow pipe (28) are connected between the buffer tank (1) and the secondary absorption tower (3). The connection between the gas supply pipe (27) and the secondary absorption tower (3) is higher than the connection between the overflow pipe (28) and the secondary absorption tower (3). The connection between the gas supply pipe (27) and the buffer tank (1) is higher than the connection between the overflow pipe (28) and the buffer tank (1). The system also includes a discharge circulation pump (7). The inlet of the discharge circulation pump (7) is connected to the buffer tank (1) through a pipe. The outlet of the discharge circulation pump (7) is connected to the second spray mechanism (9) and the first spray mechanism (10) through a pipe.

2. The water-soluble gas recovery tower according to claim 1, characterized in that, It also includes a discharge port (13), and the outlet of the discharge circulation pump (7) is connected to the discharge port (13) through a pipe.

3. The water-soluble gas recovery tower according to claim 1, characterized in that, The two ends of the heat exchanger are connected to the circulating water inlet main pipe (14) and the circulating water outlet main pipe (15) respectively. The height of the circulating water inlet main pipe (14) is lower than that of the circulating water outlet main pipe (15).

4. The water-soluble gas recovery tower according to claim 1, characterized in that, The upper end of the three-stage absorption tower (4) is provided with a demister (5), which is located above the spraying mechanism (8).

5. The water-soluble gas recovery tower according to claim 1, characterized in that, It also includes an absorption liquid system (11), which is connected to the spray mechanism three (8) through a pipe. The absorption liquid system (11) provides absorption liquid to the spray mechanism three (8). An absorption liquid inlet flow regulating valve (24) is provided on the pipe connecting the absorption liquid system (11) and the spray mechanism three (8). The inlet of the induced draft fan (6) is connected to the upper end of the three-stage absorption tower (4) through a pipe. A concentration analyzer (23) is provided on the pipe connecting the induced draft fan (6) and the three-stage absorption tower (4). The absorption liquid inlet flow regulating valve (24) is electrically connected to the concentration analyzer (23).

6. The water-soluble gas recovery tower according to claim 5, characterized in that, The buffer tank (1) is equipped with a level gauge (19), and the discharge circulation pump (7) is connected to the discharge port (13) by a discharge flow regulating valve (20), which is electrically connected to the level gauge (19).

7. The water-soluble gas recovery tower according to claim 1, characterized in that, Both the secondary absorption tower (3) and the tertiary absorption tower (4) are equipped with packing material. The packing material in the secondary absorption tower (3) is located below the second spray mechanism (9), and the packing material in the tertiary absorption tower (4) is located below the third spray mechanism (8).

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