Absorbent tank and absorbent dissolving method

Abstract

The invention discloses an absorbent dissolving tank. The dissolving tank comprises an absorbent tank, a feeding pump and an absorption liquid circulating pump; wherein the absorbent tank comprises a tank body, a feeding pipeline, a partition plate I and a partition plate II; the inner space of the absorbent tank is divided into a dissolving area, a buffer area and a storage area from top to bottom by the partition plate; the dissolving area and the buffer area are separated by a partition plate I and are communicated through an overflow pipe or an overflow weir I penetrating through the partition plate I; the buffer area and the storage area are separated by a partition plate II and are communicated through an overflow pipe or an overflow weir II penetrating through the partition plate II; a circulating liquid outlet is formed in a conical opening of the partition plate II, a circulating liquid inlet is formed in a conical opening of the partition plate I, and the circulating liquid outlet is connected with an inlet of an absorption liquid circulating pump through the tank wall; and the absorption liquid feeding pipe orifice is arranged on the pipe wall of the storage area at the lower part of the tank body. The solid-liquid and liquid-liquid mass transfer and heat transfer efficiency in the tank is improved, and the problems that absorption liquid of an existing absorbent tank is prone to cooling crystallization and insufficient in dissolving capacity are solved.

Description

Technical Field

[0001] The invention belongs to the field of flue gas desulfurization, and particularly relates to an absorbent tank and an absorbent dissolving method. Background Art

[0002] Flue gases generated during production processes in various industries, such as power, metallurgy, and petrochemicals, often contain various pollutants such as SO2, SO3, CO2, and HCl. These pollutants need to be purified and removed before discharge. Commonly used absorbents include sodium-, potassium-, magnesium-, or calcium-based alkaline substances. To meet production needs and ensure purification requirements and the longest possible use cycle of the absorbent, the absorbent is typically prepared with softened water to form a high-concentration solution, which is then stored in an absorbent tank. Because the absorbent's solubility varies significantly with ambient temperature, crystals often precipitate during storage. On-site preparation of the absorbent can be difficult due to the absorbent's solubility, requiring heating and insulation of the dissolving tank. However, due to the absorbent's large heat capacity, the heating and insulation are ineffective, often resulting in less than optimal results.

[0003] Patent CN201610018335.5 lacks any heating or stirring facilities, allowing only the preparation of relatively low-concentration solutions. Patent CN201821689037.X utilizes a jacketed dissolution tank for insulation and relies solely on a circulating pump to enhance the absorption liquid's circulation and a stirrer to dissolve solid chemicals. Insufficient stirring can lead to undissolved solids or crystals settling at the bottom of the tank.

[0004] The dual-fluid atomizing spray guns used in patents CN201610254686.6 and CN201610573963.X both use air as cooling air to prevent the spray gun barrel from evaporating and crystallizing the absorbent due to high-temperature flue gas, which can clog and wear the barrel, as well as excessive heat deformation during downtime. However, due to the relatively small heat capacity of air, a relatively large amount of cooling air is required to ensure that the absorbent does not crystallize and clog the pipe due to water evaporation and vaporization within the spray gun. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an improved absorbent dissolution tank and absorbent dissolution method. The present invention greatly improves the mass and heat transfer efficiency between the solid and liquid and between the liquid and liquid in the tank, and can overcome the problems of the absorbent in existing absorbent tanks, such as easy cooling and crystallization, and insufficient dissolution capacity.

[0006] According to a first aspect of the present invention, there is provided an absorbent dissolving tank.

[0007] The absorbent dissolving tank of the present invention comprises: (1) An absorbent tank, in which absorbent powder and softened water are mixed, dissolved, and stored; which includes: The tank body is a cylindrical structure as a whole; A feed pipe, entering the tank body from the top of the tank, is used to feed absorbent powder and softened water into the absorbent tank; Partitions I and II are inverted conical and divide the interior space of the absorbent tank into a dissolution zone, a buffer zone, and a storage zone from top to bottom; the dissolution zone and the buffer zone are separated by partition I and are connected by an overflow pipe or overflow weir I passing through partition I; the buffer zone and the storage zone are separated by partition II and are connected by an overflow pipe or overflow weir II passing through partition II; A circulating liquid outlet is provided at the tapered opening of the partition II, and a circulating liquid inlet is provided at the tapered opening of the partition I. The circulating liquid outlet is connected to the inlet of the absorption liquid circulation pump through the tank wall; The absorption liquid feeding pipe port is provided on the pipe wall of the storage area at the lower part of the tank body; (2) a feed pump for delivering the absorption liquid to the nozzle of the atomizing spray gun in the flue, the feed inlet of the feed pump being connected to the opening of the absorption liquid feed pipe, and the outlet of the feed pump being connected to the inner tube of the spray gun in the flue; (3) An absorption liquid circulation pump, which is used to feed the absorption liquid into the temperature jacket of the atomizing spray gun in the flue, and circulate the absorption liquid after heat exchange in the temperature jacket back to the absorbent tank, and spray it out through the circulating liquid inlet at the tapered mouth of the partition I.

[0008] Furthermore, the absorbent dissolution tank of the present invention also includes: (iv) an atomizing spray gun, the main body of which is located inside the flue and includes a spray gun and a jacket covering the outside of the spray gun; the liquid inlet of the jacket is connected to the outlet of the circulation pump, and the liquid outlet of the jacket is connected to the circulating liquid inlet at the tapered mouth of the partition I through a pipeline.

[0009] Furthermore, a vent is provided on the top of the absorbent dissolution tank.

[0010] Furthermore, the head of the tank body is conical, elliptical or circular.

[0011] Furthermore, a heat-insulating layer is provided on the outside, top and bottom of the absorbent dissolution tank.

[0012] Furthermore, the absorption liquid circulation pump is a slurry pump, which can be used to transport liquid containing solid particles.

[0013] Furthermore, the atomizing spray gun is a jacketed structure and can be a single-fluid atomizing spray gun or a dual-fluid atomizing spray gun. In the case of a single-fluid atomizing spray gun, the absorption liquid flows out of the absorbent tank feed pipe opening, is pumped by the absorption liquid feed pump, enters the inner tube of the atomizing spray gun, and is sprayed into the flue through the nozzle. In the case of a dual-fluid atomizing spray gun, the absorption liquid flows out of the absorbent tank feed pipe opening, is pumped by the absorption liquid feed pump, enters the inner tube of the atomizing spray gun together with compressed air, and is sprayed into the flue through the nozzle.

[0014] Furthermore, the overflow pipe I can be one or more, or an overflow weir can be used. The flow area of ​​the overflow pipe or overflow weir is 2-8 times the cross-sectional area of ​​the feed pipe, and the flow rate of the absorption liquid in the cross-sectional area of ​​the overflow pipe or overflow weir is generally 0.1-2.0 m / s.

[0015] Furthermore, the number of the overflow pipe II is one or more, and an overflow weir can also be selected, whose flow area is 2-8 times the cross-sectional area of ​​the feed pipe, and the flow rate of the absorption liquid through the overflow pipe / overflow weir cross-section is 0.1-2.0 m / s.

[0016] Furthermore, the dissolution zone overflow pipe / overflow weir I and the buffer zone overflow pipe / overflow weir II are arranged opposite to each other on the center line of the tank body.

[0017] Furthermore, the radial angle α between the partition I and the partition II and the absorbent tank is greater than the repose angle of the absorbent powder by 1 to 30 degrees.

[0018] According to a second aspect of the present invention, the present invention further provides an absorbent dissolution method, which uses the absorbent dissolution tank described above.

[0019] Specifically, the absorbent dissolving method includes the following contents: Softened water and absorbent powder in a certain proportion enter the dissolution zone of the absorbent tank through the feed pipe at the top of the absorbent tank; then enter the buffer zone through the overflow pipe / overflow weir I, and the undissolved particles or crystals slide to the conical mouth of the inverted conical partition II; Start the absorption liquid circulation pump, and the slurry composed of undissolved particles or crystals and water flows out from the circulating liquid outlet set at the tapered port of partition II, passes through the circulating pump and enters the jacket outside the spray gun set in the flue, and after heat exchange with the flue gas and rising in temperature, flows out from the circulating liquid inlet at the tapered port of partition I and enters the dissolution area of ​​the absorbent tank at a pressure 5 to 50 kPa higher than the static pressure at the circulating liquid inlet; The supernatant in the absorbent tank buffer area overflows through the overflow pipe / overflow weir II penetrating the partition II and enters the absorbent tank storage area for standby use.

[0020] Furthermore, the absorbent is selected from one or more of Na2CO3, NaHCO3, NaHSO3, Na2SO3, NaOH, K2CO3, and KHCO3.

[0021] Furthermore, the temperature of the absorbent tank is maintained at 20-40° C., and the absorbent mass concentration is 15%-45%.

[0022] Furthermore, in order to prevent dust pollution caused by the discharge of powder from the vent during the preparation of the absorption liquid, a bag filter can be added to the vent.

[0023] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention divides the absorbent dissolution tank from top to bottom into three zones: a dissolution zone, a buffer zone, and a storage zone. These zones are separated by inverted conical partitions I and II, respectively, and connected by overflow pipes / overflow weirs I and II, located on partitions I and II. The dissolution zone is always in a boiling state, facilitating mass and heat transfer between solids and liquids, and liquids and dissolution of solid particles. The buffer zone fluid is relatively stable, facilitating solid-liquid separation. The storage zone exists entirely in the form of solution overflowing through overflow pipes / overflow weir II. The absorbent dissolution tank of the present invention combines dissolution, buffering, and storage functions, making it particularly suitable for arranging boiler flue gas purification equipment within space-constrained plant areas.

[0024] 2. The present invention uses a circulating pump to pump the solid slurry from the inverted conical opening of buffer zone partition II. After being heated by heat exchange in a jacket located outside the spray gun in the flue, the circulating liquid inlet located at the conical opening of partition I enters the dissolution zone, keeping the solid-liquid mixture in the dissolution zone in a constant boiling state, accelerating solid-liquid and liquid-liquid mass and heat transfer, and dissolution of solid particles. The present invention uses the buffer zone slurry as the cooling medium for the atomizing spray gun to prevent high-temperature deformation of the atomizing spray gun and clogging of the spray gun due to evaporation and crystallization of the absorbent liquid within the spray gun. This fully utilizes the heat of the flue gas to maintain the temperature of the absorbent tank, accelerates solid dissolution, and prevents crystallization of the absorbent in the absorbent tank, ensuring flue gas purification effectiveness while also achieving energy conservation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the absorbent dissolving tank of the present invention.

[0026] Figure 2 It is a schematic diagram of the vertical structure of the dissolution zone partition and overflow pipe / overflow weir of the absorbent tank of the present invention.

[0027] Figure 3 It is a schematic diagram of the vertical structure of the buffer partition and overflow pipe / overflow weir of the absorbent tank of the present invention.

[0028] Figure 4 It is a schematic diagram of the arrangement of the overflow pipe / overflow weir and the circulating liquid inlet in the dissolution zone of the absorbent tank of the present invention.

[0029] Figure 5 It is a schematic diagram of the arrangement of the overflow pipe / overflow weir and circulating liquid outlet of the absorbent tank buffer zone of the present invention.

[0030] In the figure, 100-absorbent tank, 140-softened water pipe, 130-absorbent powder, 110-tank body, 111-absorbent tank dissolution zone, 112-absorbent tank buffer zone, 113-absorbent tank storage zone, I-absorbent tank dissolution zone overflow pipe / overflow weir, I-partition between absorbent tank dissolution zone and absorbent tank buffer zone, II-absorbent tank buffer zone overflow pipe / overflow weir, II-partition between absorbent tank buffer zone and absorbent tank storage zone, 114-circulating liquid outlet, 115-circulating liquid inlet, 116-absorbent liquid feed pipe port, 117-feed pipe, 118-vent, 200-feed pump, 300-absorbent liquid circulation pump, 400-atomizing spray gun, 410-spray gun, 411-nozzle, 412-jacket, 413-compressed air duct, 500-flue, 510-flue gas / atomized absorption liquid mixing component. DETAILED DESCRIPTION

[0031] The present invention is described in more detail below with reference to the accompanying drawings and embodiments. Example 1

[0032] like Figure 1 As shown, the absorbent dissolving tank of the present invention comprises: an absorbent tank 100, in which absorbent powder and softened water are mixed to dissolve and store the absorbent; The absorbent tank 100 includes a tank body 110 , which is a cylindrical structure as a whole; A feed pipe 117 , located at the top of the tank, is used to feed absorbent powder and softened water into the dissolution zone 111 of the absorbent tank 100 ; Partitions I and II are inverted conical and divide the interior space of the absorbent tank into a dissolution zone 111, a buffer zone 112, and a storage zone 113 from top to bottom. The dissolution zone 111 and the buffer zone 112 are separated by partition I and connected via an overflow pipe / overflow weir I penetrating partition I. The buffer zone 112 and the storage zone 113 are separated by partition II and connected via an overflow pipe / overflow weir II penetrating partition II. A circulating liquid outlet 114 is provided at the tapered opening of the partition II, and a circulating liquid inlet 115 is provided at the tapered opening of the partition I. The circulating liquid outlet 114 is connected to the inlet of the absorption liquid circulation pump 300 through the tank wall; An absorption liquid feed pipe port 116 is provided on the pipe wall of the storage area 113 of the absorbent tank 100; The feed pump 200 is used to deliver the absorption liquid to the nozzle 411 of the atomizing spray gun 410 in the flue 500. The feed port of the feed pump 200 is connected to the absorption liquid feed pipe port 116, and the outlet of the feed pump 200 is connected to the inner tube 410 of the spray gun in the flue 500; The absorption liquid circulation pump 300 is used to feed the absorption liquid into the temperature jacket 410 of the atomizing spray gun 400 in the flue, and circulate the absorption liquid after heat exchange in the temperature jacket 410 back to the absorbent tank 100 and spray it out through the circulation liquid inlet 115.

[0033] Preferably, the absorbent dissolution tank of the present invention also includes: an atomizing spray gun 400, the main body of which is located inside the flue 500, and includes a spray gun 410 and a jacket 412 covering the outside of the spray gun; the liquid inlet of the jacket 412 is connected to the outlet of the circulating pump 300, and the liquid outlet of the jacket 412 is connected to the circulating liquid inlet 115 through a pipeline.

[0034] The head of the tank body 110 of the absorbent tank 100 is conical, elliptical or circular, and a vent 118 is usually provided on the tank top.

[0035] The absorbent tank 100 is provided with a heat-insulating layer on the outside, top and bottom.

[0036] The absorption liquid circulation pump 300 is a slurry pump, which can be used to transport liquid containing solid particles.

[0037] Furthermore, the atomizing spray gun 400 is a jacketed structure and can be a single-fluid atomizing spray gun or a dual-fluid atomizing spray gun. When the atomizing spray gun is a single-fluid atomizing spray gun, the absorption liquid flows out of the feed pipe opening 116 of the absorbent tank 100, is transported by the absorption liquid feed pump 200, enters the inner tube 410 of the atomizing spray gun 400, and is sprayed into the flue through the nozzle 411. When the atomizing spray gun is a dual-fluid atomizing spray gun, the absorption liquid flows out of the feed pipe opening 116 of the absorbent tank 100, is transported by the absorption liquid feed pump 200, enters the inner tube 410 of the atomizing spray gun 400 together with compressed air 413, and is sprayed into the flue through the nozzle 411.

[0038] Furthermore, the number of the overflow pipe I is one or more, and an overflow weir can also be selected, whose flow area is 2-8 times the cross-sectional area of ​​the feed pipe, and the flow rate of the absorption liquid in the overflow pipe / overflow weir cross-section is 0.1-2.0 m / s.

[0039] Furthermore, the number of the overflow pipe II is one or more, and an overflow weir can also be selected, whose flow area is 2-8 times the cross-sectional area of ​​the feed pipe, and the flow rate of the absorption liquid in the overflow pipe / overflow weir cross-section is 0.1-2.0 m / s.

[0040] The absorbent dissolving tank and the dissolving method thereof include an absorbent tank 100, an absorption liquid circulation pump 300, softened water 140, absorbent powder 130, compressed air 413, an atomizing spray gun 400 and a flue 500, etc. Example 2

[0041] Combine Figure 1 , the absorbent dissolving method of the present invention comprises: (1) Softened water 140 and absorbent powder 130 enter the absorbent tank dissolution zone 111 through the top feed pipe 117 of the absorbent tank 100 in a certain proportion; then enter the buffer zone 112 through the overflow pipe / overflow weir I, and the undissolved particles or crystals slide to the conical mouth of the inverted conical partition II.

[0042] In order to accelerate the dissolution of the absorbent, the absorption liquid circulation pump 300 is started at the same time, and the slurry composed of undissolved particles or crystals and water flows out from the circulating liquid outlet 114 set at the tapered mouth of the partition II, passes through the circulating pump 300 and enters the jacket 412 outside the spray gun 400 set in the flue, and after heat exchange with the flue gas and heating, enters the dissolution area 111 of the absorbent tank through the circulating liquid inlet 115 at the tapered mouth of the partition I at a pressure 5 to 50 kPa higher than the static pressure at the circulating liquid inlet.

[0043] The supernatant in the absorbent tank buffer area 112 overflows through the overflow pipe / overflow weir II penetrating the partition II and enters the absorbent tank storage area 113 for standby use.

[0044] Furthermore, the temperature of the absorbent tank 100 is maintained at 20-40° C., and the absorbent mass concentration is 15%-45%. Example 3

[0045] The effective volume of an absorbent tank is 25m 3 The outlet pressure of feed pipe 115 is 30 kPa higher than the static pressure at the location. Both overflow weirs I and II have rectangular cross-sections. The fluid velocity in overflow weir I is 1.0 m / s, and in overflow weir II is 0.5 m / s. The angle α is 36°.

[0046] The absorbent is Na2SO3, and the solution concentration is 23%, which is used to remove SO3 from the flue gas. The temperature of the absorbent dissolution tank is maintained at 30℃ for insulation.

[0047] Solution preparation process: Softened water and absorbent powder enter the dissolution area of ​​the absorbent tank through the absorbent tank inlet pipe. When the liquid phase volume in the buffer zone meets the 10-minute flow rate of the circulation pump, start the absorption liquid circulation pump 300.

[0048] Implementation effect: Samples were collected near the outlets of overflow weir I and overflow weir II and the outlet pipe of absorption liquid feed pipe 116. The results are shown in Table 1.

[0049] Table 1 Sample parameters at different locations Depth, m Overflow weir Ⅰ outlet Overflow weir II outlet Absorption liquid feed pump inlet pipe Sampling sample shape The solution concentration is 16.7%, and undissolved white solid particles are visible to the naked eye. The solution is transparent, with a mass concentration of 23% The absorption liquid concentration is 23%, the solution is transparent and has no solid particles. Comparative Example 1 A conventional absorbent dissolution tank is used, and no components are set in the tank. The effective volume is the same as that of the embodiment. External heating and heat preservation and a circulation pump are used to promote dissolution.

[0050] Implementation results: The absorption liquid concentration was 18.2%, and obvious white solid particles were visible in the sample. The absorption liquid concentration at different liquid depths from the top to the bottom of the absorbent tank is shown in Table 2.

[0051] Table 2 Absorption liquid concentration at different depths Depth, m 1.0 2.0 3.0 Sampling sample shape The solution concentration is 14.5%, and undissolved white solid particles are visible to the naked eye. The solution concentration is 16.8%, and undissolved white solid particles are visible to the naked eye. The solution concentration is 18.2%, and undissolved white solid particles are visible to the naked eye.

Claims

1. An absorbent dissolution tank, characterized in that: include: (1) An absorbent tank, in which absorbent powder and softened water are mixed, dissolved, and stored; which includes: The tank body is a cylindrical structure as a whole; A feed pipe, entering the tank body from the top of the tank, is used to feed absorbent powder and softened water into the absorbent tank; Partitions I and II are inverted conical and divide the interior space of the absorbent tank into a dissolution zone, a buffer zone, and a storage zone from top to bottom; the dissolution zone and the buffer zone are separated by partition I and are connected by an overflow pipe or overflow weir I passing through partition I; the buffer zone and the storage zone are separated by partition II and are connected by an overflow pipe or overflow weir II passing through partition II; A circulating liquid outlet is provided at the tapered opening of the partition II, and a circulating liquid inlet is provided at the tapered opening of the partition I. The circulating liquid outlet is connected to the inlet of the absorption liquid circulation pump through the tank wall; The absorption liquid feeding pipe port is provided on the pipe wall of the storage area at the lower part of the tank body; (2) a feed pump for delivering the absorption liquid to the nozzle of the atomizing spray gun in the flue, the feed inlet of the feed pump being connected to the opening of the absorption liquid feed pipe, and the outlet of the feed pump being connected to the inner tube of the spray gun in the flue; (3) An absorption liquid circulation pump, which is used to feed the absorption liquid into the temperature jacket of the atomizing spray gun in the flue, and circulate the absorption liquid after heat exchange in the temperature jacket back to the absorbent tank, and spray it out through the circulating liquid inlet at the tapered mouth of the partition I.

2. The absorbent dissolution tank according to claim 1, characterized in that: The absorbent dissolution tank also includes: (iv) an atomizing spray gun, the main body of which is located inside the flue and includes a spray gun and a jacket covering the outside of the spray gun; the liquid inlet of the jacket is connected to the outlet of the circulation pump, and the liquid outlet of the jacket is connected to the circulating liquid inlet at the tapered port of the partition I through a pipeline.

3. The absorbent dissolving tank according to claim 1, characterized in that: A vent is provided on the top of the absorbent dissolving tank.

4. The absorbent dissolution tank according to claim 1, characterized in that: The exterior, top and bottom of the absorbent dissolving tank are provided with heat-insulating layers.

5. The absorbent dissolving tank according to claim 1, characterized in that: The absorption liquid circulation pump is a slurry pump and can be used to transport liquid containing solid particles.

6. The absorbent dissolving tank according to claim 1, characterized in that: The atomizing spray gun is a jacketed structure and is a single-fluid atomizing spray gun or a double-fluid atomizing spray gun.

7. The absorbent dissolving tank according to claim 6, characterized in that: The atomizing spray gun is a single-fluid atomizing spray gun, the absorption liquid flows out from the feed pipe outlet of the absorbent tank, is transported by the absorption liquid feed pump, enters the inner tube of the atomizing spray gun, and is sprayed into the flue by the nozzle; alternatively, the atomizing spray gun is a dual-fluid atomizing spray gun, the absorption liquid flows out from the feed pipe outlet of the absorbent tank, is transported by the absorption liquid feed pump, enters the inner tube of the atomizing spray gun together with the compressed air, and is sprayed into the flue by the nozzle.

8. The absorbent dissolving tank according to claim 1, characterized in that: The number of the overflow pipe I is one or more, or an overflow weir is selected.

9. The absorbent dissolving tank according to claim 8, characterized in that: The flow area of ​​the overflow pipe or overflow weir is 2-8 times the cross-sectional area of ​​the feed pipe, and the flow velocity of the absorption liquid in the cross-sectional area of ​​the overflow pipe or overflow weir is 0.1-2.0 m / s.

10. The absorbent dissolution tank according to claim 1, characterized in that: The number of the overflow pipe II is one or more, or an overflow weir is selected, and its flow area is 2-8 times the cross-sectional area of ​​the feed pipe. The flow rate of the absorption liquid through the overflow pipe / overflow weir cross-section is 0.1-2.0 m / s.

11. The absorbent dissolving tank according to claim 1, characterized in that: The dissolution zone overflow pipe / overflow weir I and the buffer zone overflow pipe / overflow weir II are arranged opposite to each other on the center line of the tank body.

12. The absorbent dissolving tank according to claim 1, characterized in that: The radial angle α between the partition I and the partition II and the absorbent tank is greater than the repose angle of the absorbent powder, which is 1 to 30 degrees.

13. An absorbent dissolution method, which uses the absorbent dissolution tank according to any one of claims 1 to 12.

14. The dissolution method according to claim 13, characterized in that Includes the following: Softened water and absorbent powder in a certain proportion enter the dissolution zone of the absorbent tank through the feed pipe at the top of the absorbent tank; then enter the buffer zone through the overflow pipe / overflow weir I, and the undissolved particles or crystals slide to the conical mouth of the inverted conical partition II; Start the absorption liquid circulation pump, and the slurry composed of undissolved particles or crystals and water flows out from the circulating liquid outlet set at the tapered port of partition II, passes through the circulating pump and enters the jacket outside the spray gun set in the flue, and after heat exchange with the flue gas and rising in temperature, flows out from the circulating liquid inlet at the tapered port of partition I and enters the dissolution area of ​​the absorbent tank at a pressure 5 to 50 kPa higher than the static pressure at the circulating liquid inlet; The supernatant in the absorbent tank buffer area overflows through the overflow pipe / overflow weir II penetrating the partition II and enters the absorbent tank storage area for standby use.

15. The dissolution method according to claim 14, characterized in that The absorbent is selected from one or more of Na2CO3, NaHCO3, NaHSO3, Na2SO3, NaOH, K2CO3, and KHCO3.

16. The dissolution method according to claim 14, characterized in that The temperature of the absorbent tank is maintained at 20-40° C., and the absorbent mass concentration is 15%-45%.

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