A hydrogen scrubbing system

Abstract

The utility model provides a kind of hydrogen washing system, comprising: washing tower, the lower part of its shell is connected to the hydrogen input pipe to be washed;Several packing sections are arranged in the shell, and the upper part of packing section is sequentially arranged liquid collection redistributor, bubble cap tray;The lower part of shell is provided with scrubbing liquid outlet, and scrubbing liquid outlet is connected with scrubbing liquid inlet on the shell through scrubbing liquid cooler, and the inlet end of scrubbing liquid is located on the upper part of bubble cap tray;The top of shell is equipped with first mist removal device;Water ring compressor, refrigerated water cooler, refrigerated water injection device and second mist removal device are sequentially arranged on hydrogen delivery pipe connected with the top outlet of washing tower, and high-purity hydrogen is output from the outlet of second mist removal device.Washing tower packing section upper part is provided with bubble cap tray, so as to enhance the mass transfer contact of hydrogen and scrubbing liquid;Combined with refrigerated water injection device, refrigerated water is injected into hydrogen delivery pipe to dissolve and absorb trace amount of alkali crystals in hydrogen, and alkali mist entrained in wet hydrogen is efficiently removed.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, specifically to a hydrogen scrubbing system. Background Technology

[0002] Hydrogen is an important basic chemical raw material that can be directly used in the synthesis of various chemicals, and can also be stored and sold as a clean fuel. In chlor-alkali chemical industry, a large amount of hydrogen can be obtained through electrolysis. However, because the high-temperature hydrogen produced by electrolysis often contains a certain amount of alkali, it needs to be washed and purified before it can be used in downstream processes, such as hydrogen chloride synthesis, fuel cells, or the use of high-purity hydrogen.

[0003] Traditional hydrogen scrubbing processes involve spray tower washing and cooling, followed by compression by a hydrogen compressor, cooling by a cooler, and water mist collection by a water mist collector before distribution to downstream processes. Understandably, as a reaction feedstock for downstream processes, the purity of the washed hydrogen plays a crucial role in the quality and performance of the final product. Incomplete removal of alkaline mist from the hydrogen will directly affect the product yield and equipment lifespan in downstream processes. For example, existing process practices have shown that high alkaline content in the outlet gas of the hydrogen spray scrubbing tower causes scaling on the hydrogen compressor blades, requiring shutdown and cleaning every three months, resulting in an average annual loss of approximately 15%. Furthermore, if incompletely de-alkaline hydrogen is used in HCl production, residual alkaline mist will undergo side reactions during combustion in the synthesis furnace, generating salts. This not only affects the furnace's production efficiency but also increases the frequency of equipment maintenance, potentially impacting the furnace's lifespan.

[0004] To improve the alkali removal rate of hydrogen output from electrolyzers, existing processes use acidic washing solutions to enhance the alkali absorption efficiency in the washing tower. However, such processes can cause equipment corrosion and reduce the alkali absorption efficiency in hydrogen due to issues such as pH fluctuations and uneven acid dispersion. Furthermore, these processes may lead to the risk of salt spray corrosion. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model discloses a hydrogen scrubbing system that can solve the problem of hydrogen alkali mist entrainment caused by incomplete scrubbing in traditional hydrogen scrubbing processes, reduce the frequency of subsequent equipment maintenance, and ensure the normal operation and service life of hydrogen utilization equipment.

[0006] To achieve the above technical objectives, this utility model proposes a hydrogen scrubbing system, which includes: a scrubbing tower comprising a shell, the lower part of which is connected to a hydrogen input pipe to be scrubbed; several packing sections are arranged inside the shell, and a liquid collector and redistributor and a bubble cap tray are sequentially arranged on the upper part of the packing sections; a scrubbing liquid outlet is provided at the lower part of the shell, and the scrubbing liquid outlet is connected to a scrubbing liquid inlet located on the shell via a scrubbing liquid cooler, the inlet end of which is located on the upper part of the bubble cap tray; a first demister is provided at the top of the shell; a water ring compressor, a chilled water cooler, a chilled water injection device, and a second demister are sequentially arranged on the hydrogen delivery pipe connected to the top outlet of the scrubbing tower, and the outlet of the second demister outputs high-purity hydrogen; wherein, the nozzle of the chilled water injection device faces the inner cavity of the hydrogen delivery pipe and is used to spray chilled water into the hydrogen delivery pipe.

[0007] The above technical solution incorporates multiple technical features for removing alkaline mist from hydrogen gas:

[0008] In the washing tower described above, a circulating and cooled washing liquid is sprayed and washed to remove alkali entrained in the wet hydrogen output from the upstream electrolysis process. The washing tower has a bubble cap tray at the top of the packed section, allowing the circulating washing liquid output from the bottom of the tower to be cooled and sprayed onto the bubble cap tray. The liquid then flows through an overflow weir or downcomer on the tray. The hydrogen to be washed enters the gas phase space above the tray through the bubble cap's riser, ensuring sufficient contact between the hydrogen and the washing liquid on the bubble cap tray for efficient mass and heat transfer, thereby absorbing and removing alkali mist from the hydrogen. The washing liquid entering the lower part of the bubble cap tray is collected by a liquid collector and redistributor and distributed back into the packed section, continuing to contact and wash the newly input hydrogen, thus enhancing the removal of alkali entrained in the hydrogen. The washed hydrogen then enters the first demister at the top of the washing tower, where a small amount of alkali droplets entrained in the extracted hydrogen are physically separated, improving the hydrogen purity. Through the washing tower of this invention, most of the alkali entrained in the input hydrogen gas is absorbed and removed.

[0009] Furthermore, after being washed, the hydrogen gas is extracted from the top of the washing tower and then compressed by a water ring compressor. This not only ensures that the hydrogen pressure meets the pressure requirements of downstream processes, but also allows the liquid ring water to dissolve and absorb a small amount of alkali crystals, further removing any alkali entrained in the hydrogen gas. The pressurized hydrogen gas is then cooled by a chilled water cooler, which removes any water that may be present in the hydrogen gas, thereby simultaneously separating any alkali that may be dissolved in the water.

[0010] Furthermore, the above technical solution also includes a chilled water injection device installed on the hydrogen delivery pipeline. By injecting chilled water into the chilled hydrogen, the trace amounts of alkaline crystals contained in the hydrogen can be dissolved. This is further combined with a demisting device to remove alkaline droplets entrained in the hydrogen, and finally, high-purity hydrogen is output from the outlet of the second demisting device.

[0011] In a further example of this utility model, the chilled water injection device includes a chilled water inlet pipe and a nozzle connected to the outlet end of the chilled water inlet pipe.

[0012] In an optional embodiment of this utility model, the chilled water input pipe includes a main pipe and an inner extension pipe; the inner extension pipe extends from the outlet end of the main pipe into the inner cavity of the hydrogen delivery pipe, and the end of the inner extension pipe is provided with a bend.

[0013] In an optional embodiment of this invention, the angle α between the extending direction of the bent portion and the extending direction of the hydrogen delivery pipe satisfies: 0° ≤ α ≤ 30°. In an optional embodiment of this invention, the angle α is 0°.

[0014] In an optional embodiment of this invention, the opening direction of the bend is the same as the conveying direction of the hydrogen delivery pipe.

[0015] In an optional embodiment of this invention, the opening direction of the bend is opposite to the delivery direction of the hydrogen delivery pipe.

[0016] In an optional embodiment of this invention, a first on / off valve and a check valve are provided on the chilled water inlet pipe. In another optional embodiment of this invention, a flow meter is provided on the chilled water inlet pipe.

[0017] In an optional embodiment of this invention, the nozzle is a spiral nozzle. In another optional embodiment of this invention, the number of nozzles is one, improving the operability of the system.

[0018] In a further example of this invention, the outlet of the water ring compressor is connected to a first branch of the hydrogen input pipe to be washed. In an optional example of this invention, a second switching valve is provided on the first branch.

[0019] In a further example of this invention, a plurality of bubble cap trays are provided at the upper part of any one of the packing sections. In an optional example of this invention, two bubble cap trays are provided at the upper part of any one of the packing sections.

[0020] In a further example of this utility model, the first demisting device is a cyclone demister or a wire mesh demister.

[0021] In a further example of this invention, the second demisting device is a demister or coalescer including a coalescing filter element. In an optional example of this invention, the high-efficiency coalescing filter element is a coalescing filter element capable of coalescing and separating droplets larger than 1 μm.

[0022] In a further example of this utility model, the packing segment is a garland-shaped packing; in an optional example of this utility model, the packing is a PP garland-shaped packing or a ceramic garland-shaped packing; in an optional example of this utility model, the packing is a PP garland-shaped packing or a ceramic garland-shaped packing with a hydrophobic modified surface.

[0023] Furthermore, the liquid collection and redistributor is one of the inclined plate type liquid collection and redistributor, the disc type liquid collection and redistributor, and the pagoda type liquid collection and redistributor, preferably the trough type liquid collection and redistributor.

[0024] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0025] This invention enhances the contact mass transfer between hydrogen and the washing liquid by installing a bubble cap tray at the top of the packing section of the washing tower, combined with a first demister, promoting the dissolution and separation of alkali entrained in the hydrogen. Further, a water ring compressor and chilled water cooler further remove the alkali entrained in the hydrogen and pressurize and cool it. A chilled water injection device dissolves trace amounts of alkali crystals contained in the hydrogen by injecting a small amount of chilled water into the hydrogen delivery pipe. The dried hydrogen is then further de-misted in a second demister to remove entrained alkaline droplets, ultimately outputting high-purity hydrogen from the outlet of the second demister. Process practice has demonstrated that this hydrogen system can efficiently remove alkali mist entrained in the wet hydrogen output from the upstream electrolysis process, achieving a removal rate of over 99.9%, meeting the needs of downstream hydrogen-using processes. This hydrogen washing system can efficiently remove alkali entrained in hydrogen without the need for acidic washing liquid, reducing equipment maintenance frequency, ensuring normal equipment operation, and extending equipment lifespan. Attached Figure Description

[0026] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0027] Figure 1 This diagram shows a structural schematic of a hydrogen scrubbing system according to the present invention.

[0028] Figure 2 This invention provides a schematic diagram of a chilled water injection device.

[0029] Figure 3This invention provides another structural schematic diagram of a hydrogen scrubbing system.

[0030] The above figures include the following reference numerals:

[0031] 11-Shell, 12-Packing section, 13-Liquid collection and redistribution device, 14-Bubble cap tray, 15-Washing liquid cooler, 16-First demister, 21-Hydrogen input pipe to be washed, 22-Hydrogen delivery pipe, 3-Water ring compressor, 31-First branch, 311-Second switching valve, 4-Chilled water cooler, 5-Chilled water injection device, 51-Chilled water input pipe, 511-Main pipe, 512-Inner extension pipe, 5121-Bend, 513-First switching valve, 514-Check valve, 515-Flow meter, 52-Nozzle, 6-Second demister. Detailed Implementation

[0032] To facilitate understanding of this utility model, a more comprehensive description of it will be provided below, along with preferred embodiments. However, it should be understood that these embodiments are merely for more detailed explanation and should not be construed as limiting the utility model in any way, i.e., not limiting the scope of protection of this utility model.

[0033] Unless otherwise defined, the technical terms used in the following embodiments have the same meanings as commonly understood by those skilled in the art to which this invention pertains. Unless otherwise specified, the experimental reagents used in the following embodiments are conventional biochemical reagents; and the experimental methods described are conventional methods.

[0034] Example 1

[0035] A hydrogen scrubbing system, such as Figure 1 As shown, the system includes:

[0036] Scrubbing tower: includes a shell 11, the lower part of which is connected to the hydrogen input pipe 21 to be scrubbed;

[0037] The shell 11 is provided with several packing sections 12. A liquid collection and redistribution device 13 and a bubble cap tray 14 are arranged sequentially on the upper part of the packing sections 12. A washing liquid outlet is provided at the lower part of the shell 11. The washing liquid outlet is connected to the washing liquid inlet located on the shell 11 via a washing liquid cooler 15. The inlet end of the washing liquid is located on the upper part of the bubble cap tray 14. A first demister 16 is provided at the top of the shell 11.

[0038] The hydrogen delivery pipe 22, which connects to the top outlet of the scrubbing tower, is sequentially equipped with: a water ring compressor 3, a chilled water cooler 4, a chilled water injection device 5, and a second demister 6. High-purity hydrogen is output from the outlet of the second demister 6. The nozzle of the chilled water injection device 5 faces the inner cavity of the hydrogen delivery pipe 22 and is used to inject chilled water into the hydrogen delivery pipe 22.

[0039] Taking the hydrogen output from the electrolysis process in the chlor-alkali process as an example, the operation process of the hydrogen scrubbing system in this embodiment can be selected as follows:

[0040] The high-temperature humid hydrogen output from the upstream electrolysis process is fed into the lower part of the scrubbing tower through the hydrogen input pipe 21. As the hydrogen flows upward, it first comes into countercurrent contact with the scrubbing liquid in the packing section 12, thereby dissolving the entrained alkali mist in the scrubbing liquid. Subsequently, it comes into mass transfer contact with the low-temperature scrubbing liquid output from the liquid collector and redistributor 13 in the bubble cap tray, enhancing the removal of the entrained alkali. At the same time, the temperature of the hydrogen is regulated and reduced through heat exchange, which helps to stabilize the hydrogen pressure to suit the gas used in subsequent processes. This also reduces the saturated vapor pressure of the hydrogen and reduces the entrained water.

[0041] The hydrogen gas, after being washed in the scrubbing tower, is transported through hydrogen delivery pipe 22 and flows sequentially through the following devices:

[0042] The gas is fed into the first demister 16 to remove alkaline droplets entrained in the gas. Compression by the water ring compressor 3 increases the pressure while simultaneously removing alkaline crystals entrained in the hydrogen through dissolution and absorption by the liquid ring water. The chilled water cooler 4 further cools and removes water from the hydrogen using chilled water at 5–7°C. Subsequently, chilled water at approximately 5–7°C is injected into the hydrogen input pipe 21 through the chilled water injection device 5 to dissolve and absorb any remaining small amounts of alkaline crystals in the hydrogen. The use of chilled water also lowers the saturated vapor pressure of the hydrogen, reducing water entrainment. The dried hydrogen is then fed into the second demister 6 for further efficient removal of trace amounts of alkaline mist, and high-purity hydrogen is output from the outlet of the second demister 6.

[0043] Optionally, the first demisting device 16 is a cyclone demister or a wire mesh demister.

[0044] Optionally, the second demisting device 6 may be a demister or coalescer including a coalescing filter element. More preferably, the high-efficiency coalescing filter element is a coalescing filter element capable of coalescing and separating droplets larger than 1 μm.

[0045] Optionally, the packing material in packing section 12 is a ring-shaped packing material. Through experiments, the researchers of this invention have found that the packing material can be further selected as a PP ring-shaped packing material or a ceramic ring-shaped packing material, which can achieve a better alkali removal effect. Even further, the packing material surface can be modified with hydrophobic PP ring-shaped packing material or ceramic ring-shaped packing material, thereby reducing alkali crystal adhesion and packing blockage. It should be noted that this invention does not limit the specific method of hydrophobic modification of the packing surface; those skilled in the art can select appropriate hydrophobically modified PP ring-shaped packing material or ceramic ring-shaped packing material as needed.

[0046] Optionally, the liquid collection and redistributor 13 is one of the inclined plate type liquid collection and redistributor, the tray type liquid collection and redistributor, and the pagoda type liquid collection and redistributor; the liquid collection and redistributor 13 is a trough type liquid collection and redistributor 13, which can uniformly spray the washing liquid onto the bubble cap tray 14 after passing through the liquid collection and redistributor 13.

[0047] Optionally, a washing liquid circulation pump is also installed on the pipeline connecting the washing liquid outlet and the washing liquid inlet to provide power for the recycling of the washing liquid.

[0048] Example 2

[0049] Based on the hydrogen scrubbing system shown in Example 1, this example optimizes the structure of the chilled water injection device 5.

[0050] like Figure 2 As shown, optionally, the chilled water injection device 5 includes a chilled water inlet pipe 51 and a nozzle 62 connected to the outlet end of the chilled water inlet pipe 51. The chilled water input from the chilled water inlet pipe 51 is sprayed into the hydrogen inlet pipe 21 to be washed through the nozzle 62 to contact with the hydrogen and dissolve and absorb the alkali crystals in the hydrogen.

[0051] Example 3

[0052] Based on the hydrogen scrubbing system shown in Embodiment 2, the specific structure of the chilled water inlet pipe 51 is not limited; chilled water can be delivered to a suitable position on the hydrogen delivery pipe 22. This embodiment further optimizes the structure of the chilled water injection device 5.

[0053] Optionally, combined Figure 2The chilled water inlet pipe 51 includes a main pipe 511 and an inner extension pipe 512. The inner extension pipe 512 extends from the outlet end of the main pipe 511 into the inner cavity of the hydrogen delivery pipe 22, and a bend 5121 is provided at the end of the inner extension pipe 512. The bend 5121 is connected to the nozzle 62. The chilled water input from the main pipe 511 is sprayed out through the bend 5121 of the inner extension pipe 512 and the nozzle 62, so that the chilled water can be delivered to a specific location more accurately. The bend 5121 is provided to facilitate the adjustment of the spray direction and coverage of the sprayed chilled water, thereby adjusting the contact angle and contact area between the water and the transmitted hydrogen.

[0054] Optionally, the angle α between the extending direction of the bend 5121 and the extending direction of the hydrogen delivery pipe 22 satisfies: 0°≤α≤30°. Adjusting the extending direction of the bend 5121 can affect the ejection direction of the nozzle 62. Optimizing the angle between the extending direction of the bend 5121 and the extending direction of the hydrogen delivery pipe 22 (0°~30°) promotes uniform and sufficient contact between chilled water and hydrogen, which is beneficial for the chilled water to dissolve and absorb alkali crystals in the hydrogen and improves cooling efficiency. Optionally, the angle α=0°.

[0055] Example 4

[0056] Based on the hydrogen scrubbing system shown in Embodiment 3, the opening direction of the bend 5121 can be selected to be the same as or opposite to the conveying direction of the hydrogen conveying pipe 22. This embodiment optimizes the opening direction of the bend 5121.

[0057] Optionally, the opening direction of the bend 5121 is the same as the conveying direction of the hydrogen conveying pipe 22, so that the injection direction of the chilled water is in the same direction as the flow direction of the hydrogen, thereby reducing the relative velocity between the chilled water and the hydrogen, reducing droplet breakage and splashing, and reducing the energy loss of the system.

[0058] Optionally, the opening direction of the bend 5121 is opposite to the conveying direction of the hydrogen conveying pipe 22, that is, the injection direction of the chilled water is opposite to the flow direction of the hydrogen, which makes the chilled water more strongly impact the hydrogen and is conducive to the chilled water better capturing alkali crystals in the hydrogen, thereby improving the purity of the hydrogen. Further, optionally, when the opening direction of the bend 5121 is opposite to the conveying direction of the hydrogen conveying pipe 22, a U-shaped water seal section is provided in the chilled water inlet pipe 51 to prevent hydrogen from backflowing into the chilled water pipeline and improve equipment safety.

[0059] Example 5

[0060] Based on the hydrogen scrubbing system shown in Example 2, the structure of the chilled water inlet pipe 51 and the nozzle 62 is optimized in this example.

[0061] Optionally, a first switching valve 513 and a check valve 514 are provided on the chilled water inlet pipe 51 to improve the operability of the chilled water injection device 5, prevent hydrogen from flowing back into the chilled water system and prevent hydrogen loss.

[0062] Alternatively, a flow meter 515 may be installed on the chilled water inlet pipe 51 to facilitate adjustment of the chilled water inlet flow rate according to the hydrogen flow rate of the hydrogen delivery pipe 22 and / or the alkaline crystal content in the hydrogen, thereby improving the adaptability and flexibility of the system of this utility model.

[0063] The specific structure and number of nozzles 62 in the hydrogen scrubbing system shown in Example 2 are not limited. Those skilled in the art can set a suitable structure and number of nozzles 62 according to actual needs.

[0064] In this embodiment, the nozzle 62 may optionally be a spiral nozzle 62, thereby achieving a more uniform spray coverage and enhancing the removal effect of alkali crystals in hydrogen.

[0065] Example 6

[0066] Based on the hydrogen scrubbing system shown in Examples 1-5, such as Figure 3 As shown, in this embodiment, a first branch 31 connected to the hydrogen input pipe 21 to be washed is provided at the outlet of the water ring compressor 3. This allows the replacement gas in the system to be compressed and pressurized and mixed with the hydrogen to be washed in the hydrogen input pipe 21 during the initial operation of the process. This increases the pressure of the hydrogen input into the washing tower, thereby optimizing the operating conditions of the washing tower. In particular, it better propels the washing liquid through the pores of the bubble cap tray 14, facilitating the efficient operation of the bubble cap tray 14.

[0067] Optionally, a second switching valve 311 is provided on the first branch 31, and the second switching valve 311 can be closed during normal operation of the hydrogen scrubbing system of this utility model.

[0068] Example 7

[0069] Based on the hydrogen scrubbing system shown in Example 1, in this embodiment, multiple bubble cap trays 14 can be optionally provided on the upper part of any packing section 12. Through extensive experiments, the developers of this invention have proven that providing multiple bubble cap trays 14 on the upper part of the packing section 12 can enhance the removal effect of alkali from hydrogen. Understandably, the number of packing sections 12 in this invention is several (including one or more), for example... Figure 1 It contains 1 packing section 12. Figure 3 It contains two packing sections 12. When multiple packing sections 12 are set in the washing tower, multiple bubble cap trays 14 can be set on the upper part of one or more packing sections 12. The specific process can be set as needed.

[0070] Alternatively, two bubble cap trays 14 may be provided at the top of any packing section 12, thereby reducing process costs.

[0071] Example 8

[0072] This embodiment demonstrates the process of hydrogen scrubbing and alkali removal using the hydrogen scrubbing system of this invention under specific operating conditions. It should be noted that this embodiment is merely a preferred embodiment and does not limit the scope of protection of this invention.

[0073] Source of hydrogen to be scrubbed: For a 300,000-ton caustic soda unit (operational flexibility upper limit 120%), the maximum flow rate of wet hydrogen (hydrogen to be scrubbed) from the electrolysis process is 5437 kg / h, of which the hydrogen mass ratio is approximately 21%. Under operating conditions (85℃, 12 kPaG), the volumetric flow rate of hydrogen entering the bottom of the hydrogen scrubbing tower is approximately 26175 m³ / h. 3 / h.

[0074] The specific washing process includes:

[0075] (1) Hydrogen gas to be washed at 85℃~90℃ enters the washing tower from the bottom of the tower. It comes into full contact with the washing liquid, which is uniformly sprayed by the liquid collector and redistributor 13, in the packed section 12 and bubble cap tray 14. The temperature of the hydrogen gas after treatment at the top of the tower is approximately 45~50℃. Note that in this example, based on the hydrogen processing capacity, the diameter of the washing tower is 3.2m, and the gas velocity inside the tower is approximately 0.9m / s. The washing liquid collected from the bottom of the tower is pressurized by the washing liquid circulation pump and sent to the washing liquid cooler 15. In the cooler, it is cooled to approximately 40℃ by circulating water. The cooled washing liquid then enters the liquid collector and redistributor 13 and is uniformly sprayed onto the surface of the bubble cap tray 14 inside the hydrogen washing tower. Based on the required diameter of the hydrogen washing tower 1 and the spray density, the flow rate of the washing liquid circulation pump is selected as 280m³ / s. 3 / h.

[0076] (2) After being washed in the scrubbing tower, the hydrogen gas passes through the first demister 16 to remove the alkaline droplets entrained in the hydrogen gas. It should be noted that in this embodiment, the first demister 16 is a cyclone demister (outer diameter 1.6m, inner diameter 0.8m) according to the hydrogen gas processing capacity.

[0077] (3) The hydrogen then enters the water ring compressor 3 and is pressurized to 0.1 MPaG by the compressor. In the water ring compressor 3, a small amount of alkaline crystals entrained in the hydrogen are dissolved and absorbed by the liquid ring water.

[0078] (4) The pressurized hydrogen is sent to the chilled water cooler 4 and cooled by chilled water at 5°C.

[0079] (5) Dry hydrogen gas at approximately 15°C at the outlet of chilled water cooler 4 is sent into the second demisting device 6; before entering the second demisting device 6, chilled water is sprayed into the hydrogen gas pipeline through the chilled water spraying device 5, thereby dissolving and absorbing trace amounts of alkali crystals carried in the dry hydrogen gas.

[0080] After undergoing the deep hydrogen scrubbing process in this embodiment, the delivered hydrogen pressure is 0.1 MPaG, the temperature is 15°C, and the alkali mist removal efficiency reaches 99.9%. The treated hydrogen is directly sent to the HCl synthesis furnace for the synthesis of HCl gas.

[0081] It should be noted that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions; the dimensional data in this embodiment do not limit the technical solution, but merely illustrate one specific working condition. For those skilled in the art to which this invention pertains, several simple improvements and modifications can be made without departing from the concept of the present invention, and all such improvements and modifications should be considered to fall within the scope of protection of the present invention.

Claims

1. A hydrogen scrubbing system, characterized in that, The system includes: Scrubbing tower: includes a shell (11), the lower part of which is connected to the hydrogen input pipe (21) to be scrubbed; The shell (11) is provided with several packing sections (12), and the upper part of the packing section (12) is provided with a liquid collection and redistributor (13) and a bubble cap tray (14) in sequence. The lower part of the shell (11) is provided with a washing liquid outlet. The washing liquid outlet is connected to the washing liquid inlet located on the shell (11) via a washing liquid cooler (15). The inlet end of the washing liquid is located on the upper part of the bubble cap tray (14). The top of the housing (11) is provided with a first defogging device (16). The hydrogen delivery pipe (22) connected to the top outlet of the washing tower is sequentially equipped with: a water ring compressor (3), a chilled water cooler (4), a chilled water injection device (5) and a second demister (6), and high-purity hydrogen is output from the outlet of the second demister (6); The nozzle of the chilled water injection device (5) is directed toward the inner cavity of the hydrogen delivery pipe (22) and is used to inject chilled water into the hydrogen delivery pipe (22).

2. The hydrogen scrubbing system according to claim 1, characterized in that, The chilled water injection device (5) includes a chilled water inlet pipe (51) and a nozzle (62) connected to the outlet end of the chilled water inlet pipe (51).

3. The hydrogen scrubbing system according to claim 2, characterized in that, The chilled water inlet pipe (51) includes a main pipe (511) and an inner extension pipe (512); the inner extension pipe (512) extends from the outlet end of the main pipe (511) into the inner cavity of the hydrogen delivery pipe (22), and the end of the inner extension pipe (512) is provided with a bend (5121).

4. The hydrogen scrubbing system according to claim 3, characterized in that, The angle α between the extension direction of the bent portion (5121) and the extension direction of the hydrogen delivery pipe (22) satisfies: 0°≤α≤30°.

5. The hydrogen scrubbing system according to claim 4, characterized in that, The included angle α is 0°.

6. The hydrogen scrubbing system according to claim 3, characterized in that, The opening direction of the bend (5121) is the same as or opposite to the delivery direction of the hydrogen delivery pipe (22).

7. The hydrogen scrubbing system according to claim 2, characterized in that, A first switching valve (513) and a check valve (514) are provided on the chilled water inlet pipe (51). And / or, the nozzle (62) is a spiral nozzle.

8. The hydrogen scrubbing system according to claim 7, characterized in that, A flow meter (515) is installed on the chilled water inlet pipe (51).

9. The hydrogen scrubbing system according to claim 7, characterized in that, The number of nozzles (62) is 1.

10. The hydrogen scrubbing system according to any one of claims 1 to 9, characterized in that, The outlet of the water ring compressor (3) is connected to the first branch (31) of the hydrogen input pipe (21) to be washed.

11. The hydrogen scrubbing system according to claim 10, characterized in that, A second switching valve (311) is installed on the first branch (31).

12. The hydrogen scrubbing system according to claim 1, characterized in that, Multiple bubble cap trays (14) are provided on the upper part of any of the packing sections (12).

13. The hydrogen scrubbing system according to claim 12, characterized in that, Two bubble cap trays (14) are provided on the upper part of any of the packing sections (12).

14. The hydrogen scrubbing system according to claim 1, characterized in that, The first demister (16) is a cyclone demister or a wire mesh demister; And / or, the second demister (6) is a demister or coalescer containing a coalescing filter element.

15. The hydrogen scrubbing system according to claim 1, characterized in that, The packing material in the packing section (12) is a garland-shaped packing material; And / or, the liquid collection and redistribution device (13) is one of the following: trough-type liquid collection and redistribution device, inclined plate-type liquid collection and redistribution device, disc-type liquid collection and redistribution device, and pagoda-type liquid collection and redistribution device.

16. The hydrogen scrubbing system according to claim 15, characterized in that, The packing material in the packing section (12) is PP garland packing or ceramic garland packing.

17. The hydrogen scrubbing system according to claim 16, characterized in that, The packing material in the packing section (12) is a PP garland packing material or a ceramic garland packing material with a hydrophobic modified surface.

18. The hydrogen scrubbing system according to claim 15, characterized in that, The liquid collection and redistribution device (13) is a trough-type liquid collection and redistribution device.

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