Composite hydrogen scrubbing device

Abstract

The utility model provides a kind of composite hydrogen washing device, it is related to hydrogen washing technical field. Including washing tower, washing tower top has hydrogen outlet, washing tower bottom has hydrogen inlet and washing liquid outlet, liquid distributor is equipped in washing tower, filler layer, wire mesh demister, wire mesh demister is located between hydrogen outlet and liquid distributor;It further includes hydrogen condensing assembly, hydrogen condensing assembly includes hydrogen delivery pipe and first heat exchanger, hydrogen delivery pipe is communicated with hydrogen inlet;The tube pass of first heat exchanger is in series with hydrogen delivery pipe.Using the utility model, high-temperature wet hydrogen produced by ion exchange membrane electrolytic cell can be cooled first, most of alkali in hydrogen is dissolved in generated condensate and separated from hydrogen, the content of alkali in hydrogen entering washing tower is reduced, and then the consumption of washing liquid is reduced;At the same time, small liquid mist carried in hydrogen after washing is removed by wire mesh demister, to avoid mist entering subsequent equipment causing corrosion and blockage.

Description

Technical Field

[0001] This utility model relates to the field of hydrogen scrubbing technology, and more specifically, to a composite hydrogen scrubbing device. Background Technology

[0002] Currently, in China's chlor-alkali production process, the treatment of high-temperature humid hydrogen produced by ion-exchange membrane electrolyzers generally employs a scrubbing tower method. This scrubbing primarily uses pure water to wash the gas, thereby removing the alkali from the hydrogen. However, this method consumes a large amount of pure water. For example, a utility model patent with Chinese authorization announcement number CN207654937U discloses a hydrogen scrubbing device, specifically stating that "the distributor refers to a liquid distribution device installed at the top of the packed tower. Its function is to evenly distribute the liquid across the cross-section of the pipe, thereby ensuring high-efficiency operation." It also states that "in use, the hydrogen to be scrubbed is introduced into the pipe through the inlet, filtered through the packing layer to remove alkaline substances and dust, then further filtered by water in the distributor, and finally scrubbed again by water sprayed from the spray pipe before being discharged from the outlet. By setting up the distributor, the water is evenly distributed, ensuring that the hydrogen to be filtered is fully scrubbed by the water liquid, resulting in a good scrubbing effect."

[0003] The pure water used in this technology becomes alkaline after a period of washing, reducing the washing effect and increasing the alkali content in the hydrogen. Pure water must be added periodically to replace the alkalinity. This process consumes too much pure water, and the high alkali content in the hydrogen also affects user experience. The washed hydrogen carries tiny liquid droplets (due to the high-speed airflow potentially carrying some droplets during gas-liquid contact), which also contain alkali. If these droplets enter subsequent equipment, they can cause corrosion, blockages, and other problems. Utility Model Content

[0004] The purpose of this invention is to provide a composite hydrogen scrubbing device, which can first cool the high-temperature humid hydrogen produced by the ion membrane electrolyzer, so that most of the alkali in the hydrogen dissolves in the generated condensate and separates from the hydrogen, thereby reducing the alkali content in the hydrogen entering the scrubbing tower and thus reducing the consumption of scrubbing liquid; at the same time, a wire mesh demister removes the tiny liquid mist carried in the hydrogen after scrubbing, preventing the mist from entering subsequent equipment and causing corrosion and blockage.

[0005] The technical solution adopted in this utility model is as follows:

[0006] This application provides a composite hydrogen scrubbing device, including a scrubbing tower with a hydrogen outlet at the top and a hydrogen inlet and a scrubbing liquid outlet at the bottom. A liquid distributor and a packing layer are arranged sequentially from top to bottom inside the scrubbing tower. A wire mesh demister is provided inside the scrubbing tower, located between the hydrogen outlet and the liquid distributor.

[0007] It also includes a hydrogen condensation assembly, which includes a hydrogen delivery pipe and a first heat exchanger. The hydrogen delivery pipe is connected to the hydrogen inlet; the tube side of the first heat exchanger is connected in series with the hydrogen delivery pipe.

[0008] Furthermore, in some embodiments of this utility model, the hydrogen condensation assembly further includes a water seal, one end of which is connected to the tube side of the first heat exchanger.

[0009] Furthermore, in some embodiments of this utility model, the hydrogen scrubbing device further includes a condensate recovery component, which includes:

[0010] A condensate recovery tank is located below the water seal and is used to collect condensate overflowing from the water seal.

[0011] The recovery liquid delivery pipe is connected at one end to the condensate recovery tank;

[0012] A recovery liquid transfer pump is installed in the recovery liquid transfer pipe.

[0013] Furthermore, in some embodiments of this utility model, a gas distributor is provided inside the scrubbing tower, and the gas distributor is located between the packing layer and the hydrogen inlet.

[0014] Furthermore, in some embodiments of this utility model, at least two packing restricting grid plates are provided at intervals inside the washing tower, and packing restricting grid plates are provided at the top and bottom of the packing layer.

[0015] Furthermore, in some embodiments of this utility model, the hydrogen scrubbing device further includes a scrubbing liquid circulation assembly, which includes a scrubbing liquid circulation pipe and a second heat exchanger, a flow meter, and a scrubbing liquid circulation pump connected in series with the scrubbing liquid circulation pipe; one end of the scrubbing liquid circulation pipe is connected to the inlet end of the liquid distributor, and the other end of the scrubbing liquid circulation pipe is connected to the scrubbing liquid outlet.

[0016] Compared with the prior art, the embodiments of this utility model have at least the following advantages or beneficial effects:

[0017] The hydrogen scrubbing device provided in this application can first cool down the high-temperature humid hydrogen produced by the ion membrane electrolyzer, so that most of the alkali in the hydrogen dissolves in the generated condensate and separates from the hydrogen, thereby reducing the alkali content in the hydrogen entering the scrubbing tower and thus reducing the consumption of scrubbing liquid; at the same time, the wire mesh demister removes the tiny liquid droplets carried in the hydrogen after scrubbing, preventing the droplets from entering subsequent equipment and causing corrosion and blockage. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the hydrogen scrubbing device provided in an embodiment of the present invention;

[0020] Figure 2 A partial cross-sectional view of the interior of the washing tower provided in an embodiment of this utility model;

[0021] Figure 3 A partial cross-sectional view of the tube side and water seal of the first heat exchanger provided in an embodiment of this utility model.

[0022] icon:

[0023] 10-Scrubber; 11-Hydrogen outlet; 12-Hydrogen inlet; 13-Scrubber liquid outlet; 14-Liquid distributor; 15-Packing layer; 16-Wire mesh demister; 17-Gas distributor; 18-Packing restrictor grid plate;

[0024] 20-Hydrogen condenser assembly; 21-Hydrogen delivery pipe; 22-First heat exchanger; 221-Tube side; 23-Water seal;

[0025] 30 - Condensate recovery assembly; 31 - Condensate recovery tank; 32 - Recovered liquid delivery pipe; 33 - Recovered liquid delivery pump;

[0026] 40-Washing liquid circulation assembly; 41-Washing liquid circulation pipe; 42-Second heat exchanger; 43-Flow meter; 44-Washing liquid circulation pump. Detailed Implementation

[0027] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0028] Example

[0029] Please refer to Figures 1-3 This embodiment provides a composite hydrogen scrubbing device, including a scrubbing tower 10. The top of the scrubbing tower 10 has a hydrogen outlet 11, from which the scrubbed hydrogen is discharged. The hydrogen outlet 11 can be connected to an external hydrogen compressor. The bottom of the scrubbing tower 10 has a hydrogen inlet 12 and a scrubbing liquid outlet 13. The hydrogen inlet 12 is used to introduce the hydrogen to be scrubbed into the scrubbing tower 10, and the scrubbing liquid, after scrubbing the hydrogen, is discharged from the scrubbing tower 10 through the scrubbing liquid outlet 13.

[0030] The scrubbing tower 10 contains a liquid distributor 14 and a packing layer 15 arranged sequentially from top to bottom. The liquid distributor 14 is a conventional product, and its function is to evenly distribute the scrubbing liquid to the top of the packing layer 15, ensuring that the surface of the packing is fully covered by liquid to form a continuous liquid film, thereby maximizing the gas-liquid contact area and ensuring the scrubbing effect. The packing layer 15 uses existing products such as Raschig rings and Pall rings. As the core area for gas-liquid contact, the packing provides a large specific surface area (surface area per unit volume of packing), allowing hydrogen to fully contact the scrubbing liquid sprayed from the top of the tower, removing impurities from the hydrogen through absorption, adsorption, or condensation. The packing is usually granular (such as Raschig rings or Pall rings), stacked between the packing restricting grid plates 18 inside the tower. The scrubbing liquid is evenly sprayed from the top of the upper packing by the liquid distributor 14 and flows downward along the surface of the packing (forming a liquid film); hydrogen flows upward from the bottom of the lower packing, contacting the liquid film in the opposite direction. The scrubbing tower 10 is equipped with a wire mesh demister 16, which is located between the hydrogen outlet 11 and the liquid distributor 14. The wire mesh demister is a gas-liquid separation device. When the gas passes through the wire pad of the wire mesh demister 16, the mist entrained in the gas can be removed.

[0031] It also includes a hydrogen condensation assembly 20, which includes a hydrogen delivery pipe 21 and a first heat exchanger 22. The hydrogen delivery pipe 21 is connected to the hydrogen inlet 12; the tube side 221 of the first heat exchanger 22 is connected in series with the hydrogen delivery pipe 21. In this embodiment, the first heat exchanger 22 is a shell-and-tube heat exchanger made of stainless steel and is a horizontal heat exchanger. The shell-and-tube heat exchanger has a shell side and a tube side 221. When wet hydrogen is transported through the hydrogen delivery pipe 21, it passes through the tube side 221 of the shell-and-tube heat exchanger, while cooling water passes through the shell side of the shell-and-tube heat exchanger to cool the wet hydrogen.

[0032] In the specific implementation process, the high-temperature humid hydrogen produced by the ion-exchange membrane electrolyzer is input through one end of the hydrogen delivery pipe 21 and passes through the tube side 221 of the first heat exchanger 22. Cooling water cools the humid hydrogen through the shell side of the tube heat exchanger. At this time, the high-temperature humid hydrogen produces condensate after cooling. Most of the alkali in the hydrogen dissolves in the condensate and is separated from the hydrogen. Then, the cooled hydrogen is transported into the scrubbing tower 10 through the hydrogen delivery pipe 21. Since most of the alkali in the hydrogen dissolves in the condensate and is separated from the hydrogen, the alkali content in the hydrogen entering the scrubbing tower 10 is reduced, thereby reducing the consumption of scrubbing liquid.

[0033] Hydrogen gas passes through the packing layer 15 and the liquid distributor 14 from bottom to top within the scrubbing tower 10. During this process, the scrubbing liquid is evenly distributed to the top of the packing layer 15 via the liquid distributor 14, ensuring that the packing surface is fully covered by liquid, forming a continuous liquid film, thereby maximizing the gas-liquid contact area and ensuring the scrubbing effect. After scrubbing, the hydrogen gas passes through the wire mesh demister 16 and then exits the scrubbing tower 10 through the hydrogen outlet 11. During the process of the hydrogen gas passing through the wire mesh demister 16, the wire mesh demister 16 removes the mist entrained in the hydrogen gas, preventing the mist from entering subsequent equipment and causing corrosion and blockage.

[0034] like Figures 1-3 As shown, in some embodiments, the hydrogen condensation assembly 20 further includes a water seal 23, one end of which is connected to the tube side 221 of the first heat exchanger 22. The hydrogen scrubbing device also includes a condensate recovery assembly 30, which includes a condensate recovery tank 31, a recovery liquid delivery pipe 32, and a recovery liquid delivery pump 33. The condensate recovery tank 31 is located below the water seal 23 and is used to collect the condensate overflowing from the water seal 23. One end of the recovery liquid delivery pipe 32 is connected to the condensate recovery tank 31, and the recovery liquid delivery pump 33 is located on the recovery liquid delivery pipe 32.

[0035] The main function of water seal 23 is to maintain the airtightness of the system. The water seal is a closed space formed by a water-filled bend in the pipe, using water to isolate gas within the pipe system. When condensate is generated and flows through the discharge pipe, the water seal ensures that gas will not be discharged from the system along with the condensate.

[0036] This invention, by setting up a water seal 23 and a condensate recovery assembly 30, allows the condensate produced after hydrogen gas is cooled by the first heat exchanger 22 to flow into the water seal 23 through the tube side 221 of the first heat exchanger 22. Figure 3 As shown, with the increase of condensate, the condensate can overflow through the water seal 23 and drip into the condensate recovery tank 31 below. In this way, the condensate containing alkali can be collected through the condensate recovery tank 31. Subsequently, the collected condensate can be transported out through the recovery liquid transfer pump 33 and the recovery liquid transfer pipe 32 and used for emergency chlorination or dechlorination of brine, which facilitates the recycling of the condensate and creates economic value.

[0037] like Figures 1-2 As shown, in some embodiments, a gas distributor 17 is provided inside the scrubbing tower 10, located between the packing layer 15 and the hydrogen inlet 12. The gas distributor 17 is an existing product, and its function is to evenly distribute the hydrogen entering the scrubbing tower 10 across the tower cross-section, preventing gas flow deviation or excessively high local flow velocities, and ensuring sufficient contact between the gas and the subsequent packing layer 15 and scrubbing liquid.

[0038] like Figures 1-2As shown, in some embodiments, at least two packing restricting grid plates 18 are spaced apart inside the scrubbing tower 10, and packing restricting grid plates 18 are provided at both the top and bottom of the packing layer 15. For example... Figure 2 As shown, in this embodiment, three packing restricting grid plates 18 are used, and two packing layers 15 are used. The packing restricting grid plates 18 have a porous structure and are used to restrict the packing, allowing hydrogen and washing liquid to flow through.

[0039] like Figures 1-3 As shown, in some embodiments, the hydrogen scrubbing device further includes a scrubbing liquid circulation assembly 40, which includes a scrubbing liquid circulation pipe 41 and a second heat exchanger 42, a flow meter 43 and a scrubbing liquid circulation pump 44 connected in series with the scrubbing liquid circulation pipe 41; one end of the scrubbing liquid circulation pipe 41 is connected to the liquid inlet of the liquid distributor 14 and the other end of the scrubbing liquid circulation pipe 41 is connected to the scrubbing liquid outlet 13.

[0040] In this embodiment, the washing liquid circulation pump 44 is made of carbon steel and is a centrifugal pump. It is used to send the washing liquid to the liquid distributor 14 at the top of the washing tower 10, thereby achieving the effect of washing liquid circulation. The second heat exchanger 42 is made of stainless steel and is a plate heat exchanger, used for cooling the washing liquid. The flow meter 43 is a rotor flow meter used to observe the washing liquid circulation volume. By setting up the washing liquid circulation assembly 40, the washing liquid generated after hydrogen washing flows out from the washing liquid outlet 13, is transported by the washing liquid circulation pump 44 to the second heat exchanger 42 for cooling, and then transported back to the washing tower 10, which facilitates the recycling of the washing liquid.

[0041] Furthermore, unless otherwise explicitly specified or limited, the terms "installation" and "connection" in this application embodiment should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. The terms "upper," "lower," "left," "right," "inner," "outer," and "side," etc., are merely for reference to the direction in the accompanying drawings or the usual placement of the product during use. They are only for clearly describing this application and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limitations on this application. The terms "first," "second," etc., are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance; "multiple" refers to at least two. In this application embodiment, the limitations on relative positional relationships such as parallel, perpendicular, and aligned are all relative to the current technological level and are not absolutely strict limitations. Slight deviations are allowed; approximations of parallel, perpendicular, and aligned are all acceptable. For example, "A and B are parallel" means that A and B are parallel or approximately parallel, and the angle between A and B can be between 0 degrees and 10 degrees.

[0042] The above are only some embodiments and implementation methods of this application. The protection scope of this application is not limited thereto. In the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other. Any combination of features in different embodiments is also within the protection scope of this application. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application.

Claims

1. A composite hydrogen scrubbing device, comprising a scrubbing tower, wherein the scrubbing tower has a hydrogen outlet at the top and a hydrogen inlet and a scrubbing liquid outlet at the bottom, and wherein a liquid distributor and a packing layer are arranged sequentially from top to bottom inside the scrubbing tower; characterized in that, The scrubbing tower is equipped with a wire mesh demister, which is located between the hydrogen outlet and the liquid distributor. It also includes a hydrogen condensation assembly, which includes a hydrogen delivery pipe and a first heat exchanger. The hydrogen delivery pipe is connected to the hydrogen inlet; the tube side of the first heat exchanger is connected in series with the hydrogen delivery pipe.

2. The composite hydrogen scrubbing device according to claim 1, characterized in that, The hydrogen condensation assembly also includes a water seal, one end of which is connected to the tube side of the first heat exchanger.

3. The composite hydrogen scrubbing device according to claim 2, characterized in that, The hydrogen scrubbing device further includes a condensate recovery component, which comprises: A condensate recovery tank is located below the water seal and is used to collect the condensate overflowing from the water seal. A recovery liquid delivery pipe, one end of which is connected to the condensate recovery tank; A recovery liquid transfer pump is installed in the recovery liquid transfer pipe.

4. A composite hydrogen scrubbing device according to any one of claims 1-3, characterized in that, The scrubbing tower is equipped with a gas distributor, which is located between the packing layer and the hydrogen inlet.

5. A composite hydrogen scrubbing device according to any one of claims 1-3, characterized in that, The washing tower is provided with at least two packing restricting grid plates at intervals, and the packing restricting grid plates are provided at the top and bottom of the packing layer.

6. A composite hydrogen scrubbing device according to any one of claims 1-3, characterized in that, The hydrogen scrubbing device further includes a scrubbing liquid circulation assembly, which includes a scrubbing liquid circulation pipe and a second heat exchanger, a flow meter, and a scrubbing liquid circulation pump connected in series with the scrubbing liquid circulation pipe; one end of the scrubbing liquid circulation pipe is connected to the inlet end of the liquid distributor, and the other end of the scrubbing liquid circulation pipe is connected to the scrubbing liquid outlet.

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