Hydrogen washing system

Abstract

The invention provides a hydrogen washing system which comprises a washing tower, the lower part of a shell of the washing tower is connected with a to-be-washed hydrogen input pipe; a plurality of filler sections are arranged in the shell, and a liquid collection redistributor and a bubble cap tray are sequentially arranged at the upper parts of the filler sections; the lower part of the shell is provided with a washing liquid outlet, the washing liquid outlet is connected with a washing liquid inlet positioned on the shell through a washing liquid cooler, and the inlet end of the washing liquid is positioned at the upper part of the bubble cap tray; a first demisting device is arranged at the top of the shell; a water-ring compressor, a chilled water cooler, a chilled water spraying device and a second demisting device are sequentially arranged on a hydrogen conveying pipe connected with the extraction opening in the top of the washing tower, and high-purity hydrogen is output from an outlet of the second demisting device. A bubble-cap tray is arranged at the upper part of the filler section of the washing tower, so that mass transfer contact between hydrogen and washing liquid is enhanced; and chilled water is sprayed into the hydrogen conveying pipe by combining the chilled water spraying device to dissolve and absorb trace alkali crystals in hydrogen, so that alkali mist entrained in the wet hydrogen is efficiently removed.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical equipment, and in particular to a hydrogen scrubbing system. Background Art

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

[0003] The traditional hydrogen scrubbing process involves scrubbing and cooling in a spray tower, followed by compression in a hydrogen compressor, cooling in a cooler, and mist capture in a mist collector before distribution to downstream processes. Understandably, as a raw material for downstream reactions, the purity of the scrubbed hydrogen plays a critical role in the quality and performance of the final product. Incomplete removal of alkaline mist from the hydrogen directly impacts the yield of downstream processes and the lifespan of equipment. For example, existing process practices have shown that high alkaline content in the outlet gas from a hydrogen spray scrubber causes scaling of the hydrogen compressor blades, requiring downtime and cleaning every three months, resulting in an average annual loss of approximately 15%. If incompletely de-alkalified hydrogen is used in HCl production, the residual alkaline mist in the hydrogen will react with the combustion of the synthesis furnace lamps to produce salts, impacting the furnace's production efficiency and increasing the frequency of equipment maintenance, which can severely impact the furnace's lifespan.

[0004] To improve the alkali removal rate of hydrogen output from the electrolyzer, existing processes use acidic washing liquids for washing to enhance the absorption efficiency of alkali in the washing tower. However, due to problems such as pH control fluctuations and uneven acid addition dispersion, such processes will cause corrosion to the equipment and reduce the absorption efficiency of alkali in hydrogen. Such processes may also lead to the risk of entrained salt spray corrosion. Summary of the Invention

[0005] In response to the deficiencies in the prior art, the present invention discloses a hydrogen scrubbing system that can solve the problem of hydrogen alkaline mist entrainment caused by incomplete scrubbing in traditional hydrogen scrubbing processes, reduce the inspection and maintenance frequency of subsequent equipment, and ensure the normal operation and service life of hydrogen utilization equipment.

[0006] To achieve the above technical objectives, the present invention provides a hydrogen scrubbing system, comprising: a scrubbing tower comprising a shell, the lower portion of which is connected to a hydrogen inlet pipe to be scrubbed; a plurality of packing sections disposed within the shell, a liquid collecting and redistributing device and a bubble cap tray disposed in sequence above the packing sections; a scrubbing liquid outlet disposed at the lower portion of the shell, the scrubbing liquid outlet being connected to a scrubbing liquid inlet located on the shell via a scrubbing liquid cooler, the scrubbing liquid inlet being located above the bubble cap tray; a first demister disposed at the top of the shell; a hydrogen delivery pipe connected to the scrubbing tower top outlet being provided with: a water ring compressor, a chilled water cooler, a chilled water spraying device, and a second demister, wherein high-purity hydrogen is output from the outlet of the second demister; wherein the nozzle of the chilled water spraying device is directed toward 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 has multiple technical features for removing alkaline mist from hydrogen:

[0008] In the scrubbing tower of the above technical solution, alkali entrained in the wet hydrogen output from the upstream electrolysis process is removed by spraying and washing with circulating cooled scrubbing liquid. A bubble cap tray is provided above the packing section of the scrubbing tower, so that the circulating scrubbing liquid output from the lower portion of the scrubbing tower is cooled and sprayed onto the bubble cap tray, flowing through an overflow weir or downcomer on the tray. The hydrogen to be scrubbed then enters the gas phase space above the tray through the bubble cap riser. This allows the hydrogen to fully contact the scrubbing liquid on the bubble cap tray, achieving efficient mass and heat transfer, thereby absorbing and removing alkali mist from the hydrogen. The scrubbing liquid entering the lower portion of the bubble cap tray is collected by a liquid collector and redistributor and distributed in the packing section, where it continues to contact and wash with newly input hydrogen to be scrubbed, thereby enhancing the removal of alkali entrained in the hydrogen. The scrubbed hydrogen enters a first demister at the top of the scrubbing tower, which physically separates small amounts of alkali droplets entrained in the produced hydrogen, thereby improving hydrogen purity. By washing in the washing tower of the present invention, most of the alkali entrained in the input hydrogen is absorbed and removed.

[0009] Furthermore, after the washed hydrogen is extracted from the top of the washing tower and output, it is compressed by a water ring compressor, which not only makes the hydrogen pressure meet the pressure requirements of the gas used in the downstream process, but also dissolves and absorbs a small amount of alkali crystals through liquid ring water, thereby further removing the alkali entrained in the hydrogen; by cooling the pressurized hydrogen through a chilled water cooler, part of the water that may be contained in the hydrogen can be removed, and the alkali that may be dissolved in the water can be separated synchronously.

[0010] Furthermore, the above technical solution also provides a chilled water injection device on the hydrogen transmission pipeline. By spraying chilled water into the frozen hydrogen, the trace alkali crystals contained in the hydrogen can be dissolved. The alkaline droplets entrained in the hydrogen can be removed by further combining with the demisting device, and finally high-purity hydrogen is output from the outlet of the second demisting device.

[0011] In a further example of the present invention, the chilled water spraying device includes a chilled water input pipe and a spray head connected to an outlet end of the chilled water input pipe.

[0012] In an optional example of the present invention, 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 to the inner cavity of the hydrogen delivery pipe, and a bending portion is provided at the end of the inner extension pipe.

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

[0014] In an optional example of the present invention, the opening direction of the bent portion is the same as the delivery direction of the hydrogen delivery pipe.

[0015] In an optional example of the present invention, the opening direction of the bent portion is opposite to the conveying direction of the hydrogen conveying pipe.

[0016] In an optional example of the present invention, a first switch valve and a check valve are provided on the chilled water input pipe. In an optional example of the present invention, a flow meter is provided on the chilled water input pipe.

[0017] In an optional example of the present invention, the nozzle is a spiral nozzle. In an optional example of the present invention, the number of the nozzle is one, which improves the operability of the system.

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

[0019] In a further example of the present invention, a plurality of bubble cap trays are provided on the top of any of the packing sections. In an optional example of the present invention, two bubble cap trays are provided on the top of any of the packing sections.

[0020] In a further example of the present invention, the first demisting device is a cyclone plate demisting device or a wire mesh demisting device.

[0021] In a further example of the present invention, the second demisting device is a demister or coalescer comprising a coalescing filter element. In an optional example of the present invention, the high-efficiency coalescing filter element is a coalescing filter element that can coalesce and separate droplets larger than 1 μm.

[0022] In a further example of the present invention, the filler of the filler section is a garland-type filler; in an optional example of the present invention, the filler is a PP garland-type filler or a ceramic garland-type filler; in an optional example of the present invention, the filler is a PP garland-type filler or a ceramic garland-type filler with a hydrophobically modified surface.

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

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention, by installing a bubble cap tray at the top of the packing section of the scrubbing tower and combining it with a first demisting device, strengthens the contact and mass transfer between hydrogen and scrubbing liquid, promoting the dissolution and separation of alkali entrained in the hydrogen. Furthermore, a water ring compressor and a chilled water cooler are combined to further remove alkali entrained in the hydrogen and increase the pressure and cool the hydrogen. A chilled water injection device dissolves trace 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-entrained by alkaline droplets in the second demisting device, and high-purity hydrogen is finally output from the outlet of the second demisting device. Process practice has proven that the hydrogen system of the present invention can efficiently remove alkaline mist entrained in the wet hydrogen output from the upstream electrolysis process, with a removal rate of over 99.9%, meeting the production needs of downstream hydrogen-using processes. The hydrogen scrubbing system of the present invention can efficiently remove alkali entrained in hydrogen without the need to add acidic scrubbing liquid, reducing the frequency of equipment inspection and maintenance, ensuring the normal operation of the equipment, and increasing its service life. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0027] Figure 1 A structural schematic diagram of a hydrogen scrubbing system according to the present invention is shown;

[0028] Figure 2 A schematic structural diagram of a chilled water injection device in the present invention is shown;

[0029] Figure 3 Another structural schematic diagram of a hydrogen scrubbing system according to the present invention is shown;

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

[0031] 11-shell, 12-packing section, 13-liquid collection and redistributor, 14-bubble tray, 15-washing liquid cooler, 16-first demisting device, 21-hydrogen inlet pipe to be washed, 22-hydrogen delivery pipe, 3-water ring compressor, 31-first branch, 311-second switch valve, 4-chilled water cooler, 5-chilled water injection device, 51-chilled water inlet pipe, 511-main pipe, 512-inner extension pipe, 5121-bend, 513-first switch valve, 514-check valve, 515-flow meter, 52-sprinkler, 6-second demisting device. DETAILED DESCRIPTION

[0032] To facilitate understanding of the present invention, the present invention will be described in more detail below, with preferred embodiments of the present invention provided. However, it should be understood that these embodiments are merely for the purpose of further explanation and are not to be construed as limiting the present invention in any form, i.e., they are not intended to limit the scope of protection of the present invention.

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

[0034] Example 1

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

[0036] The scrubbing tower comprises a shell 11, the lower portion of which is connected to a hydrogen inlet pipe 21 to be scrubbed;

[0037] Several packing sections 12 are provided within the housing 11. A liquid collecting and redistributing device 13 and a bubble cap tray 14 are sequentially provided above the packing sections 12. A washing liquid outlet is provided at the bottom of the housing 11. The washing liquid outlet is connected to a washing liquid inlet located on the housing 11 via a washing liquid cooler 15. The washing liquid inlet is located above the bubble cap tray 14. A first demisting device 16 is provided at the top of the housing 11.

[0038] The hydrogen delivery pipe 22 connected to the top outlet of the scrubbing tower is provided with: a water ring compressor 3, a chilled water cooler 4, a chilled water injection device 5 and a second demister 6 in sequence, and high-purity hydrogen is output from the outlet of the second demister 6; wherein, 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.

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

[0040] The high-temperature wet hydrogen output from the upstream electrolysis process is input into the lower part of the washing tower through the hydrogen to be washed input pipe 21. During the upward flow of the hydrogen, it first contacts the washing liquid in the packing section 12 in a countercurrent manner, thereby dissolving the alkaline mist entrained therein; then, it contacts the low-temperature washing liquid output from the liquid collection and redistributor 13 in the bubble tower plate by mass transfer, thereby enhancing the effect of removing the entrained alkali. At the same time, the temperature of the hydrogen is adjusted and lowered through heat exchange, which is conducive to stabilizing the hydrogen pressure to be suitable for gas use in subsequent processes, thereby reducing the saturated vapor pressure of the hydrogen and reducing the entrained water.

[0041] The hydrogen after washing in the washing tower is transported through the hydrogen delivery pipe 22 and flows through the following devices in sequence:

[0042] The hydrogen is then fed into the first demisting device 16 to remove alkali droplets entrained in the gas. The water ring compressor 3 compresses the hydrogen, increasing its pressure while simultaneously removing alkali crystals entrained in the hydrogen through dissolution and absorption by the liquid ring water. The chilled water cooler 4 further cools and dehydrates the hydrogen using chilled water at 5-7°C. Subsequently, chilled water at approximately 5-7°C is sprayed into the hydrogen inlet pipe 21 to be washed via the chilled water injection device 5 to dissolve and absorb any small amounts of alkali crystals still entrained in the hydrogen. The use of chilled water also reduces the saturated vapor pressure of the hydrogen, reducing water entrainment. The dried hydrogen is then fed into the second demisting device 6 to further efficiently remove trace amounts of alkali mist entrained in the hydrogen, and high-purity hydrogen is output from the outlet of the second demisting device 6.

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

[0044] Optionally, the second demister 6 can be a demister or coalescer comprising a coalescing filter element. Further optionally, the high-efficiency coalescing filter element is a coalescing filter element that can coalesce and separate droplets larger than 1 μm.

[0045] Optionally, the filler of filler section 12 is a rosette-shaped filler. Through experiments, the researchers of the present invention have found that the filler can further be a PP rosette-shaped filler or a ceramic rosette-shaped filler, which can achieve a better alkali removal effect. Furthermore, the PP rosette-shaped filler or the ceramic rosette-shaped filler can be a filler with a hydrophobic surface modification to reduce the adhesion of alkali crystals and clogging of the filler. It should be noted that the present invention is not limited to the specific method of hydrophobic surface modification of the filler. Those skilled in the art can select a suitable PP rosette-shaped filler or ceramic rosette-shaped filler with a hydrophobic surface modification as needed.

[0046] Optionally, the liquid collecting and redistributor 13 is one of an inclined plate type liquid collecting and redistributor, a disc type liquid collecting and redistributor and a pagoda type liquid collecting and redistributor; the liquid collecting and redistributor 13 is a trough type liquid collecting and redistributor 13, and the washing liquid can be evenly sprayed onto the bubble tower plate 14 after passing through the liquid collecting and redistributor 13.

[0047] Optionally, a washing liquid circulation pump is further provided on the pipeline connecting the washing liquid collection 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 embodiment 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 input pipe 51 and a nozzle 62 connected to the outlet end of the chilled water input pipe 51. The chilled water input from the chilled water input pipe 51 is sprayed into the hydrogen input pipe 21 to be washed through the nozzle 62 to contact the hydrogen, dissolve and absorb the alkali crystals in the hydrogen.

[0051] Example 3

[0052] Based on the hydrogen scrubbing system shown in Example 2, the specific structure of the chilled water input pipe 51 is not limited, and the chilled water can be delivered to a suitable position of the hydrogen delivery pipe 22. In this embodiment, the structure of the chilled water injection device 5 is further optimized.

[0053] Optionally, combined Figure 2 The chilled water input 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. A bend 5121 is provided at the end of the inner extension pipe 512. The bend 5121 connects to the nozzle 62. Chilled water input from the main pipe 511 is sprayed through the bend 5121 of the inner extension pipe 512 and the nozzle 62, thereby more accurately delivering the chilled water to a specific location. The provision of the bend 5121 facilitates adjustment of the spray direction and coverage of the sprayed chilled water, thereby adjusting the contact angle and contact area between the chilled water and the transmitted hydrogen.

[0054] Further optionally, the angle α between the extension direction of the bend 5121 and the extension direction of the hydrogen delivery pipe 22 satisfies the following: 0°≤α≤30°. Adjusting the extension direction of the bend 5121 can affect the spray direction of the nozzle 62. Optimizing the angle between the extension direction of the bend 5121 and the extension direction of the hydrogen delivery pipe 22 to be 0° to 30° promotes uniform and sufficient contact between the chilled water and the hydrogen, facilitating the chilled water to dissolve and absorb alkali crystals in the hydrogen and improving cooling efficiency. Further optionally, the angle α = 0°.

[0055] Example 4

[0056] Based on the hydrogen scrubbing system shown in Example 3, the opening direction of the bent portion 5121 can be selected to be the same as or opposite to the delivery direction of the hydrogen delivery pipe 22. In this embodiment, the opening direction of the bent portion 5121 is optimized.

[0057] Optionally, the opening direction of the bend 5121 is the same as the delivery direction of the hydrogen delivery pipe 22, so that the spray direction of the chilled water is the same as the flow direction of the hydrogen, thereby reducing the relative speed between the chilled water and the hydrogen, reducing the breakage and splashing of droplets, and reducing the energy loss of the system.

[0058] Optionally, the opening direction of the bend 5121 is opposite to the delivery direction of the hydrogen delivery pipe 22. That is, the chilled water spray direction is opposite to the flow direction of the hydrogen. This allows the chilled water to more strongly impact the hydrogen and helps the chilled water better capture alkali crystals in the hydrogen, thereby improving the purity of the hydrogen. Furthermore, when the opening direction of the bend 5121 is opposite to the delivery direction of the hydrogen delivery pipe 22, a U-shaped water seal section is provided on the chilled water inlet pipe 51 to prevent hydrogen from flowing back into the chilled water pipeline, thereby improving equipment safety.

[0059] Example 5

[0060] Based on the hydrogen scrubbing system shown in Example 2, the structures of the chilled water input pipe 51 and the nozzle 62 are optimized in this embodiment.

[0061] Optionally, a first switch valve 513 and a check valve 514 are provided on the chilled water input 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] Further optionally, a flow meter 515 is provided on the chilled water input pipe 51 to adjust the chilled water input flow rate according to the hydrogen flow rate of the hydrogen delivery pipe 22 and / or the alkali crystal content in the hydrogen, thereby improving the adaptability and flexibility of the system of the present invention.

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

[0064] In this embodiment, optionally, the nozzle 62 is a spiral nozzle 62, so as to achieve a more uniform spray coverage range and enhance the removal effect of alkali crystals in hydrogen.

[0065] Example 6

[0066] Based on the hydrogen scrubbing system shown in Examples 1 to 5, Figure 3 As shown, in this embodiment, a first branch 31 connected to the hydrogen to be washed inlet pipe 21 is provided at the outlet of the water ring compressor 3, so that when the process is initially run, the replacement gas in the system can be compressed and pressurized and mixed with the hydrogen to be washed in the hydrogen to be washed inlet pipe 21, which can increase the pressure of the hydrogen input to the washing tower, thereby optimizing the operating conditions of the washing tower, especially better promoting the washing liquid to pass through the pores of the bubble tower tray 14, thereby facilitating the efficient operation of the bubble tower tray 14.

[0067] Optionally, a second switch valve 311 is provided on the first branch 31 , and the second switch valve 311 can be optionally closed when the hydrogen scrubbing system of the present invention operates normally.

[0068] Example 7

[0069] Based on the hydrogen scrubbing system shown in Example 1, multiple bubble cap trays 14 can be optionally provided on the upper portion of any packing section 12 in this embodiment. The researchers of the present invention have proved through a large number of experiments that providing multiple bubble cap trays 14 on the upper portion of the packing section 12 can enhance the alkali removal effect in hydrogen. It is understandable that the number of packing sections 12 in the present invention is several (including one or more), such as Figure 1 It includes a packing section 12, Figure 3 There are two packing sections 12. When a plurality of packing sections 12 are provided in the washing tower, a plurality of bubble cap trays 14 can be optionally provided on top of one or more packing sections 12. The arrangement can be made as required in the specific process.

[0070] Further optionally, two bubble cap trays 14 are provided on the top of any filling 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 the present invention under specific working conditions. It should be noted that this embodiment is only a preferred example and does not limit the scope of protection of the present invention.

[0073] Source of hydrogen to be scrubbed: For a 300,000-ton caustic soda plant (with an upper limit of 120% operating flexibility), the maximum flow rate of wet hydrogen (hydrogen to be scrubbed) from the electrolysis process is 5437 kg / h, of which the mass ratio of hydrogen is approximately 21%. Under operating conditions (85°C, 12 kPaG), the volume flow rate of hydrogen entering the hydrogen scrubber kettle is approximately 26175 m 3 / h.

[0074] The specific washing process includes:

[0075] (1) The hydrogen gas to be washed at 85℃~90℃ enters the washing tower from the bottom of the tower, and is fully contacted with the washing liquid uniformly sprayed by the liquid collecting and redistributor 13 in the packing section 12 and the bubble cap tray 14. The temperature of the hydrogen gas after being treated by the hydrogen washing tower at the top of the tower is about 45~50℃. It should be noted that in this example, according to the hydrogen processing capacity, the diameter of the washing tower is 3.2m, and the gas velocity in the tower is about 0.9m / s; the washing liquid extracted 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 about 40℃ by circulating water, and the cooled washing liquid enters the liquid collecting and redistributor 13, and after passing through the distributor, it is evenly sprayed to the surface of the bubble cap tray 14 in the hydrogen washing tower; according to the diameter of the hydrogen washing tower 1 and the spraying density requirements, the flow rate of the washing liquid circulation pump is selected to be 280m 3 / h.

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

[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 alkali 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, where it is cooled by 5°C chilled water.

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

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

[0081] It should be noted that the above content is a further detailed description of the present invention in conjunction with specific implementation methods, and the specific implementation of the present invention cannot be considered to be limited to these descriptions; the dimensional data of this embodiment does not limit the technical solution of this invention, but only illustrates one specific working condition. For those skilled in the art of the technology to which this invention belongs, simple improvements and modifications can be made without departing from the concept of the present invention, and all of these should be considered to fall within the scope of protection of this invention.

Claims

1. A hydrogen scrubbing system, characterized in that: The system comprises: The washing tower comprises a shell (11), the lower portion of which is connected to a hydrogen gas input pipe (21) to be washed; A plurality of packing sections (12) are arranged in the shell (11), and a liquid collecting and redistributing device (13) and a bubble cap tray (14) are sequentially arranged on the upper part of the packing section (12); A washing liquid outlet is provided at the lower portion of the shell (11), the washing liquid outlet is connected to a washing liquid inlet located on the shell (11) via a washing liquid cooler (15), and the washing liquid inlet end is located at the upper portion of the bubble cap tray (14); A first demisting device (16) is provided on the top of the housing (11); A hydrogen delivery pipe (22) connected to the top outlet of the scrubbing tower is provided with: a water ring compressor (3), a chilled water cooler (4), a chilled water injection device (5) and a second demisting device (6) in sequence, and high-purity hydrogen is output from the outlet of the second demisting device (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 spraying device (5) comprises a chilled water input pipe (51) and a spray head (62) connected to the outlet end of the chilled water input pipe (51).

3. The hydrogen scrubbing system according to claim 2, characterized in that: The chilled water input pipe (51) comprises 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) to the inner cavity of the hydrogen delivery pipe (22), and a bent portion (5121) is provided at the end of the inner extension pipe (512).

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

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

6. The hydrogen scrubbing system according to claim 2, characterized in that: A first switch valve (513) and a check valve (514) are provided on the chilled water input pipe (51); Preferably, a flow meter (515) is provided on the chilled water input pipe (51); and / or, the nozzle (62) is a spiral nozzle; Preferably, the number of the nozzle (62) is one.

7. The hydrogen scrubbing system according to any one of claims 1 to 6, characterized in that: The outlet of the water ring compressor (3) is provided with a first branch (31) connected to the hydrogen gas input pipe (21) to be washed; Preferably, a second switch valve (311) is provided on the first branch (31).

8. The hydrogen scrubbing system according to claim 1, characterized in that: A plurality of bubble cap trays (14) are arranged on the upper portion of any of the packing sections (12); Preferably, two bubble cap trays (14) are provided on the top of any one of the packing sections (12).

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

10. The hydrogen scrubbing system according to claim 1, characterized in that: The filler of the packing section (12) is a rosette-type filler, preferably a PP rosette-type filler or a ceramic rosette-type filler, and further preferably a PP rosette-type filler or a ceramic rosette-type filler whose surface is hydrophobically modified; And / or, the liquid collecting and redistributing device (13) is one of an inclined plate type liquid collecting and redistributing device, a disc type liquid collecting and redistributing device and a pagoda type liquid collecting and redistributing device, preferably a trough type liquid collecting and redistributing device.

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