Hydrogen drying device and hydrogen recovery method for hydrogen production in chlor-alkali industry

Abstract

The present application relates to a hydrogen drying device and a hydrogen recovery method for hydrogen production in the chlor-alkali industry, comprising a main pipeline, the main pipeline comprising an "I"-shaped middle piece and two connecting pipes; the middle piece comprising two parallel connecting plates and an intermediate plate fixed between the two connecting plates, both sides of the intermediate plate forming an installation area, the connecting plates on both sides of the installation area are provided with a plurality of vents, the two connecting pipes respectively correspond to the two connecting plates, and the connecting pipes are fixed to the connecting plates; a drying box is slidably connected in the installation area, the two ends of the drying box are provided with a plurality of vents, the drying box is connected to the two connecting pipes through the vents and the vents; a plurality of desiccant sheets are arranged at intervals in the drying box. The above arrangement facilitates the replacement of the desiccant.

Description

Technical Field

[0001] The present application relates to the technical field of hydrogen recovery in the chlor-alkali industry, and in particular to a hydrogen drying device and a hydrogen recovery method for hydrogen production in the chlor-alkali industry. Background Art

[0002] The chlor-alkali industry is a vital component of the chemical industry, primarily producing basic chemicals such as chlorine, hydrogen, and caustic soda (sodium hydroxide). Its products have a wide range of uses in the national economy. With the development of new energy sources in my country, hydrogen, as a high-quality renewable energy source, has become increasingly important. The waste gas generated by the chlor-alkali industry is rich in hydrogen, making its utilization particularly critical. The current hydrogen recovery process requires the separation of water vapor from the gas. Condensation is a common method, where the purified hydrogen is discharged into a condenser for water vapor separation. To ensure hydrogen purity, after discharge from the condenser, the hydrogen is typically poured into a desiccant-equipped device for final drying. Currently, desiccant replacement is required after a period of use, which is inconvenient. Summary of the Invention

[0003] In order to improve the problem of inconvenient replacement of desiccant in the current hydrogen recovery process. The present application provides a hydrogen drying device for hydrogen production in the chlor-alkali industry, comprising a main pipeline, wherein the main pipeline comprises an "I"-shaped middle piece and two connecting pipes; the middle piece comprises two parallel connecting plates, and an intermediate plate fixed between the two connecting plates, both sides of the intermediate plate form an installation area, and the connecting plates on both sides of the installation area are provided with a plurality of vents, and the two connecting pipes correspond one to one with the two connecting plates, and the connecting pipes are fixed to the connecting plates;

[0004] A drying box is slidably connected in the installation area, and a plurality of air holes are opened at both ends of the drying box. The drying box is connected to the two connecting pipes through the air holes and the vent holes;

[0005] A plurality of desiccant sheets are arranged at intervals in the drying box.

[0006] By adopting the above solution, if the desiccant sheet in the drying box needs to be replaced after prolonged use, it can be removed from the installation area by sliding the drying box. During this process, the presence of two drying boxes ensures that the main pipeline remains unobstructed, thereby improving hydrogen production efficiency. Furthermore, cavities are provided in the connecting plates on both sides of the installation area. These cavities pass through the vents, and an operating hole is provided on the side of the connecting plate facing the middle plate, which communicates with the cavities.

[0007] A partition plate is slidably connected in the cavity, and the partition plate includes a main body and a force-bearing part. The main body is slidably connected to the cavity, and a plurality of connecting holes are opened on the main body. The plurality of connecting holes are used in a one-to-one correspondence with the plurality of vent holes. The force-bearing part extends into the installation area through the operation hole. An elastic member is provided between the force-bearing part and the intermediate plate. Under the action of the elastic member, the vent holes are aligned with the connecting holes.

[0008] A locking piece is provided between the drying box and the main pipeline. After the drying box is installed in the installation area, the air holes, the vent holes and the connecting holes are aligned, and the drying box is fixed by the locking piece.

[0009] By adopting the above solution, after the drying box is installed in the installation area, the drying box presses on the force-bearing portion, connecting the connection hole on the partition plate with the vent hole. At this time, the state of the drying box is fixed by the locking member. After the drying box is removed from the installation area, the partition plate loses its positional restraint by the drying box. At this time, the partition plate moves away from the middle plate under the action of the elastic member, causing the connection hole and the vent hole to be misaligned. The vent hole is now sealed, minimizing gas leakage during the desiccant replacement process.

[0010] Furthermore, the elastic member includes a push rod rotatably connected to the middle plate, and a torsion spring installed between the push rod and the middle plate.

[0011] By adopting the above solution, the cooperation between the push rod and the torsion spring can reduce the space occupied by the elastic member as much as possible.

[0012] Furthermore, a hidden groove is provided on the middle plate, the elastic member is located in the hidden groove, and after the drying box is installed in the installation area, the force-bearing portion of the partition plate is hidden in the hidden groove.

[0013] By adopting the above solution, the outer surface of the drying device is made smoother and the utilization area of ​​the connecting plate is increased.

[0014] Furthermore, the drying box includes a box body, both ends of which are provided with sliding grooves for use with the force-bearing part, and the force-bearing part is aligned with the sliding grooves;

[0015] The drying box further comprises a pushing member slidably connected to the sliding groove, an elastic member being fixedly connected between the pushing member and the drying box, and under the action of the elastic member, a side of the pushing member facing the middle plate is flush with a side of the drying box facing the middle plate, and when the box body is installed in the installation area, the pushing member presses the force-bearing portion into the hidden groove;

[0016] A track is provided in the sliding groove along the length direction of the sliding groove, a sliding member is slidably connected to the side of the pushing member away from the middle plate in the sliding groove, a slider is fixedly connected to the sliding member, and the slider is slidably connected to the track, a handheld plate is provided on the side of the box away from the middle plate, the sliding member is fixedly connected to the handheld plate, and a pull rope is fixedly connected between the sliding member and the pushing member;

[0017] When the slider slides to the end of the track away from the middle plate, the connecting hole on the partition plate and the vent hole on the connecting plate are in a misaligned state.

[0018] By adopting the above solution, after the box body is installed in the installation area, the pusher presses the force-bearing part into the hidden groove under the action of the elastic member so that the vent hole is aligned and connected with the connecting hole. When removing the drying box from the installation area, the handheld plate is first pulled to the side away from the middle plate. During this process, the handheld plate drives the pusher to move away from the middle plate through the pull rope. At this time, the force-bearing part of the partition plate moves away from the middle plate under the action of the elastic member so that the vent hole is gradually closed. When the slider moves to the end of the track away from the middle plate, the vent hole is completely closed. At this time, the handheld plate is continued to be pulled to separate the box body from the magnet and then from the installation area. In this way, the vent hole is completely closed before the box body moves away from the middle plate, thereby avoiding gas leakage as much as possible.

[0019] Furthermore, grooves are provided on the edges of the connecting plates on both sides of the installation area. Under the action of the elastic member, the handheld plate is attached to the drying box, and both sides of the handheld plate extend into the grooves.

[0020] By adopting the above solution, the sealing between the drying box and the main pipeline is further improved.

[0021] Furthermore, a placement groove is provided on a side of the box body facing the handheld plate, and a push rod is hinged in the placement groove.

[0022] By adopting the above solution, during the process of removing the box body from the installation area, before the box body is disengaged from the locking piece, the free end of the push rod is rotated to make the free end of the push rod abut against the hand-held plate. At this time, the state between the hand-held plate and the box body is fixed. After the box body is disengaged from the magnet, the hand-held plate will not stick to the box body due to the action of the elastic piece. After the desiccant is replaced, the staff will first install the box body into the installation area. During this process, the vent hole will not open due to the action of the push rod. After the box body is installed, the push rod is rotated to make the push rod enter the arrangement groove. At this time, the hand-held plate sticks to the box body under the action of the elastic piece, and the vent hole is opened, thereby avoiding gas leakage during the installation of the drying box into the installation area as much as possible.

[0023] Furthermore, the drying box includes a main body and a cover plate, the main body is provided with an opening, the cover plate can be detachably installed to the opening of the box body, a mounting rack is provided in the main body, a plurality of tooling areas are provided on the mounting rack, a plurality of the desiccant sheets correspond one-to-one to the plurality of the tooling areas, and the desiccant sheets are slidably connected to the tooling areas.

[0024] By adopting the above solution, it is easy to replace the desiccant.

[0025] A method for recovering hydrogen in the chlor-alkali industry using a drying device comprises the following steps:

[0026] S1, dechlorination process;

[0027] The gas from the electrolysis process enters the elution tower, where the hydrogen is sprayed and scrubbed with sodium sulfide solution to remove chlorine;

[0028] S2, raw gas compression process;

[0029] The hydrogen-containing tail gas, after chlorine is removed, enters the cyclone separator to remove the water carried in the tail gas. The hydrogen compressor pressurizes the tail gas, usually to 0.8MPa. The pressurized hydrogen enters the steam-water separator to remove the water.

[0030] S3, deoxidation and drying process

[0031] After the hydrogen has been dehydrated by the steam-water separator, it enters the deoxidizer to remove oxygen from the hydrogen. It is then cooled by the hydrogen cooler. The cooled gas then enters the cooling condenser, where it is further cooled with chilled water to remove water. The gas is then introduced into the hydrogen drying device through its air inlet. The gas enters the chamber through the vents and air holes, where it passes through multiple layers of desiccant sheets to further remove any residual moisture.

[0032] S4, pressure swing adsorption process

[0033] The cooled gas enters the pressure swing adsorption device to adsorb and remove nitrogen and a small amount of impurity gas in the hydrogen.

[0034] By adopting the above technical solution, high-purity hydrogen can be produced efficiently and quickly.

[0035] In summary, the present invention has at least the following beneficial effects:

[0036] 1. By setting up two groups of drying ovens, the drying ovens can be replaced alternately, thereby improving the efficiency of hydrogen production.

[0037] 2. Through the cooperation of the pushing member, the elastic member, the hand-held member and the force-bearing part, after the box body is installed in the installation area, the pushing member presses the force-bearing part into the hidden groove under the action of the elastic member so that the vent hole is aligned and connected with the connection hole. When removing the drying box from the installation area, first pull the hand-held plate to the side away from the middle plate. During this process, the hand-held plate drives the pushing member to move away from the middle plate through the pull rope. At this time, the force-bearing part of the partition plate moves away from the middle plate under the action of the elastic member, so that the vent hole is gradually closed. When the slider moves to the end of the track away from the middle plate, the vent hole is completely closed. At this time, continue to pull the hand-held plate to separate the box body from the magnet and then from the installation area. In this way, the vent hole is completely closed before the box body moves away from the middle plate, thus avoiding gas leakage as much as possible.

[0038] 3. By setting a push rod between the handheld plate and the box body, during the process of removing the box body from the installation area, before the box body is disengaged from the locking piece, the free end of the push rod is rotated to make the free end of the push rod abut against the handheld plate. At this time, the state between the handheld plate and the box body is fixed. After the box body is disengaged from the magnet, the handheld plate will not be attached to the box body due to the action of the elastic member. After the desiccant is replaced, the staff will first install the box body into the installation area. During this process, the vent hole will not be opened due to the action of the push rod. After the box body is installed, the push rod is rotated to make the push rod enter the arrangement groove. At this time, the handheld plate is attached to the box body under the action of the elastic member, and the vent hole is opened, so as to avoid gas leakage during the installation of the drying box into the installation area as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a schematic diagram showing the overall structure of the drying device in this embodiment;

[0040] Figure 2 is a schematic diagram showing the middleware structure in this embodiment;

[0041] Figure 3 Schematic diagram showing the structure of the drying box in this embodiment;

[0042] Figure 4 is a schematic diagram showing the internal structure of the connecting plate in this embodiment;

[0043] Figure 5 yes Figure 4 A partial enlarged schematic diagram of part B;

[0044] Figure 6 yes Figure 3 A partial enlarged schematic diagram of part A;

[0045] Figure 7 This is a schematic diagram showing the structure of the pusher in the embodiment of the present application;

[0046] Figure 8 This is a schematic diagram showing the arrangement structure of the ejector pins on the drying oven in an embodiment of the present application;

[0047] Figure 9 yes Figure 8 A partial enlarged schematic diagram of part C in the middle;

[0048] Figure 10 It is a schematic diagram showing the mounting frame structure in an embodiment of the present application.

[0049] Description of reference numerals:

[0050] 1. Main pipe; 11. Air inlet; 12. Air outlet; 13. Intermediate piece; 131. Connecting plate; 1311. Air vent; 1312. Groove; 1313. Cavity; 1314. Operation hole; 132. Intermediate plate; 1321. Hidden slot; 1322. Mounting slot; 1323. Jack; 1324. Mounting hole; 1325. Screw; 133. Mounting area; 14. Connecting pipe; 2. Drying oven; 21. Box body; 211. Air vent; 212. Sliding slot; 21 3. Track; 214. Layout groove; 2141. Push rod; 215. Main body; 216. Cover plate; 217. Latch; 218. Perforation; 22. Push member; 221. Elastic member; 23. Handle plate; 24. Sliding member; 241. Sliding block; 242. Through hole; 25. Pull rope; 3. Partition plate; 31. Main body; 311. Connecting hole; 32. Force-bearing part; 4. Elastic member; 41. Push rod; 5. Locking member; 6. Mounting frame; 61. Work area; 611. Desiccant sheet. DETAILED DESCRIPTION

[0051] The hydrogen drying device for hydrogen production in the chlor-alkali industry provided in the application embodiment is referred to Figure 1 and Figure 2 , including a main pipeline 1, one end of the main pipeline 1 is an air inlet 11, and the other end of the main pipeline 1 is an air outlet 12. Specifically, the main pipeline 1 includes an "I"-shaped middle piece 13, and two connecting pipes 14 arranged at both ends of the middle piece 13, and the cross-section of the connecting pipe 14 is circular. The middle piece 13 includes two parallel connecting plates 131, and the connecting plate 131 is a circular plate. An intermediate plate 132 is fixed between the two connecting plates 131, and installation areas 133 are formed on both sides of the intermediate plate 132. The two connecting plates 131 correspond to the two connecting pipes 14 one by one. The connecting pipe is coaxially fixed to the side of the connecting plate 131 away from the intermediate plate 132. Vents 1311 are provided on the connecting plates 131 on both sides of the installation area 133, and the connecting pipe 14 is connected to the installation area 133 through the vents 1311.

[0052] The drying box 2 is slidably connected in the installation area 133 .

[0053] Reference Figure 3A plurality of air holes 211 are provided at both ends of the drying box 2. When the drying box 2 is installed in the installation area 133, the air holes 211 are aligned with the vent holes 1311, and the connecting pipe 14 is connected to the drying box 2 through the vent holes 1311 and the air holes 211.

[0054] Several desiccant sheets 611 are evenly arranged in the drying box 2. The desiccant can be activated carbon or the like.

[0055] When the desiccant sheet 611 in the drying box 2 needs to be replaced after a long period of use, the drying box 2 can be slid out of the installation area 133 for replacement. In this process, two drying boxes 2 can be replaced alternately, which can always keep the main pipeline 1 unobstructed and improve hydrogen production efficiency.

[0056] Reference Figure 4 During the desiccant replacement process, in order to prevent the gas in the main pipeline 1 from leaking outward through the vent holes 1311 as much as possible. A cavity 1313 is provided in the connecting plates 131 on both sides of the installation area 133. The cavity 1313 passes through a plurality of vent holes 1311. An operating hole 1314 communicating with the cavity 1313 is provided on the side of the connecting plate 131 facing the middle plate 132. A partition plate 3 is slidably connected in the cavity 1313. The partition plate 3 includes an integral main body 31 and a force-bearing portion 32. The main body 31 is slidably connected to the cavity 1313. A plurality of connecting holes 311 are provided on the main body 31. The plurality of connecting holes 311 correspond one-to-one to the plurality of vent holes 1311 on the connecting plate 131.

[0057] Reference Figure 4 and Figure 5 The force-bearing portion 32 extends downward through the operating hole 1314 into the mounting area 133. An elastic member 4 is provided between the partition plate 3 and the middle plate 132. Under the action of the elastic member 4, the connection hole 311 on the partition plate 3 and the vent hole 1311 on the connection plate 131 are misaligned.

[0058] Reference Figure 2 A locking member 5 is also provided between the drying box 2 and the intermediate member 13. The locking member 5 can be a bolt, a screw, etc. In this case, the locking member 5 is a magnet. Specifically, a mounting groove 1322 is provided on the intermediate plate 132, and the locking member 5 is fixed to the mounting groove 1322. After the drying box 2 is installed in the installation area 133, the drying box 2 presses the force-bearing portion 32, so that the connection hole 311 on the partition plate 3 is connected to the vent hole 1311, and the state of the drying box 2 is fixed by the locking member 5. After the drying box 2 is removed from the installation area 133, the partition plate 3 loses the position limit of the drying box 2. At this time, the partition plate 3 moves away from the intermediate plate 132 under the action of the elastic member 4, so that the connection hole 311 and the vent hole 1311 are misaligned. At this time, the vent hole 1311 is closed, and gas leakage during the desiccant replacement process is avoided as much as possible.

[0059] Reference Figure 4 and Figure 5 Specifically, the elastic member 4 includes a push rod 41 having one end hinged to the middle plate 132, a torsion spring is provided between the push rod 41 and the connecting plate 131, and the other free end of the push rod 41 abuts against the force-bearing portion 32 of the partition plate 3. Under the action of the torsion spring, the free end of the push rod 41 can push the partition plate 3 to move away from the middle plate 132. At the same time, the cooperation between the push rod 41 and the torsion spring can minimize the space occupied by the elastic member 4.

[0060] To smooth the drying device's exterior and maximize the usable surface area of ​​the connecting plate 131, the intermediate plate 132 is provided with a recessed groove 1321 for accommodating the elastic member 4 and the partition plate 3. After the drying oven 2 is mounted in the mounting area 133, the surface of the drying oven 2 facing the intermediate plate 132 abuts against the intermediate plate 132, and the force-bearing portion 32 of the partition plate 3 enters the recessed groove 1321.

[0061] Reference Figure 3 The drying box 2 includes a box body 21, and the end surfaces of both ends of the box body 21 are provided with sliding grooves 212 used in conjunction with the force-bearing part 32, and the force-bearing part 32 is aligned with the sliding grooves 212.

[0062] Reference Figure 6 and Figure 7 The drying box 2 also includes two pushers 22 for use with the sliding grooves 212. The two pushers 22 correspond one-to-one with the two sliding grooves 212. The pushers 22 are slidably connected to the sliding grooves 212. An elastic member 221 is fixedly connected between the pushers 22 and the box body 21. The elastic member 221 is a spring. Under the action of the elastic member 221, the end of the pusher 22 facing the middle plate 132 is flush with the side of the box body 21 facing the middle plate 132. The drying box 2 also includes a handheld plate 23 mounted on the side of the box body 21 away from the middle plate 132. A track 213 is defined in the sliding grooves 212. A sliding member 24 is slidably connected to the corresponding sliding grooves 212. The sliding member 24 is located on the side of the pusher 22 away from the middle plate 132. A slider 241 is fixedly connected to the side wall of the slider 24. The slider 241 is slidably connected to the track 213. A through hole 242 is opened on the sliding member 24 along the length direction of the sliding groove 212. A pull rope 25 is fixed between the pushing member 22 and the handheld plate 23. One end of the pull rope 25 is fixed to the pushing member 22, and the other end of the pull rope 25 passes through the through hole 242 and is fixed to the handheld plate 23.

[0063] After the box body 21 is installed in the installation area 133 , the elastic member 221 acts to push the force-bearing portion 32 of the pushing member 22 into the hidden groove 1321 so that the vent hole 1311 is aligned with the connecting hole 311 and communicates with each other. When removing the drying box 2 from the installation area 133, the hand-held plate 23 is first pulled to move toward the side away from the middle plate 132. During this process, the hand-held plate 23 drives the pushing member 22 to move in the direction away from the middle plate 132 through the pull rope 25. At this time, the force-bearing portion 32 of the partition plate 3 moves in the direction away from the middle plate 132 under the action of the elastic member 4, so that the vent 1311 is gradually closed, and when the slider 241 moves to the end of the track 213 away from the middle plate 132, the vent 1311 is completely closed. At this time, continue to pull the hand-held plate 23 to separate the box body 21 from the magnet and then from the installation area 133. In this way, the vent 1311 is completely closed before the box body 21 moves away from the middle plate 132, thereby avoiding gas leakage as much as possible.

[0064] Reference Figure 2 , grooves 1312 are provided on the edges of the connecting plates 131 on both sides of the installation area 133. After the box body 21 is installed to the installation area 133, the edges of the hand-held plate 23 are located in the grooves 1312 under the action of the elastic member 221, further improving the sealing between the drying box 2 and the main pipeline 1.

[0065] Reference Figure 8 and Figure 9 A placement groove 214 is formed on one side of the box body 21 facing the hand-held plate 23 , and a push rod 2141 is connected to the placement groove 214 . When the box 21 is removed from the installation area 133, the free end of the push rod 2141 is rotated to make the free end of the push rod 2141 contact with the hand-held plate 23 before the box 21 is disengaged from the locking member 5. At this time, the state between the hand-held plate 23 and the box 21 is fixed. After the box 21 is separated from the magnet, the hand-held plate 23 will not stick to the box 21 due to the action of the elastic member 221. After the desiccant is replaced, the staff first installs the box 21 into the installation area 133. In this process, due to the action of the push rod 2141, the vent 1311 will not open. After the box 21 is installed, the push rod 2141 is rotated to make the push rod 2141 enter the arrangement groove 214. At this time, the hand-held plate 23 is stuck to the box 21 under the action of the elastic member 221, and the vent 1311 is opened, so as to avoid gas leakage during the installation of the drying box 2 to the installation area 133 as much as possible.

[0066] Reference Figure 3 The box body 21 includes a main body 215 and a cover plate 216. The main body 215 is provided with an opening on one side facing the middle plate 132. The cover plate 216 is detachably mounted to the opening position of the main body 215 by bolts or screws.

[0067] Reference Figure 10 A mounting frame 6 is provided in the main body 215, and a plurality of tooling areas 61 are evenly spaced on the mounting frame 6. A plurality of desiccant sheets 611 correspond one to one with the tooling areas 61. The desiccant sheets 611 are slidably connected to the tooling areas 61 to facilitate replacement of the desiccant in the box body 21.

[0068] Reference Figure 2 and Figure 3 In order to avoid the drying device from being accidentally touched by the staff in the working state, causing the position of the drying device to change and affecting normal operation, a latch 217 is fixedly connected to the side of the box body 21 facing the middle plate 132, and a through hole 218 is provided on the latch 217. Correspondingly, a socket 1323 for cooperating with the latch 217 is provided on the middle plate 132, and a mounting hole 1324 is provided on the side wall. The mounting hole 1324 passes through the socket 1323, and a screw 1325 is connected to the inner thread of the mounting hole 1324. When the box body 21 is installed to the middle piece 13, the latch 217 extends into the socket 1323, and the through hole 218 is aligned with the mounting hole 1324. At this time, the staff can lock the drying box 2 by screwing the screw 1325 to make the screw 1325 pass through the through hole 218.

[0069] The implementation principle of this case is as follows: in the process of removing the drying box 2 from the installation area 133, the hand-held plate 23 is first pulled to move to the side away from the middle plate 132. In this process, the hand-held plate 23 drives the pushing member 22 to move in the direction away from the middle plate 132 through the pull rope 25. At this time, the force-bearing portion 32 of the partition plate 3 moves in the direction away from the middle plate 132 under the action of the elastic member 4, so that the vent 1311 is gradually closed, and when the slider 241 moves to the end of the track 213 away from the middle plate 132, the vent 1311 is completely closed. Before the box body 21 disengages from the locking member 5, the free end of the top rod 2141 is rotated to make the free end of the top rod 2141 abut against the hand-held plate 23, and then the hand-held plate 23 is continued to be pulled to make the box body 21 disengage from the magnet and then disengage from the installation area 133. In this way, before the box body 21 moves away from the middle plate 132, the vent 1311 is completely sealed, and gas leakage is avoided as much as possible. After the box body 21 is separated from the installation area 133, the staff can remove the desiccant sheet 611 in the drying box 2 from the cover plate 216 for replacement. In this process, due to the presence of two drying boxes 2, the main pipeline 1 can always be kept unobstructed, thereby improving the hydrogen production efficiency. After the desiccant is replaced, the staff first installs the box body 21 into the installation area 133. In this process, due to the action of the top rod 2141, the vent 1311 will not open. After the box body 21 is installed, the top rod 2141 is rotated to make the top rod 2141 enter the arrangement groove 214. At this time, the handheld plate 23 is attached to the box body 21 under the action of the elastic member 221, and the vent 1311 is opened, thereby avoiding gas leakage during the installation of the drying box 2 into the installation area 133 as much as possible.

[0070] A method for recovering hydrogen in the chlor-alkali industry comprises the following steps:

[0071] S1, dechlorination process;

[0072] The gas from the electrolysis process enters the scrubbing tower, where the hydrogen is sprayed and scrubbed with sodium sulfide solution. The sodium sulfide solution reacts with the chlorine in the hydrogen to produce sulfide and sodium chloride, thereby removing the chlorine.

[0073] S2, raw gas compression process;

[0074] The hydrogen-containing tail gas, after chlorine is removed, enters the cyclone separator to remove the water carried in the tail gas. The hydrogen compressor pressurizes the tail gas, usually to 0.8MPa. The pressurized hydrogen enters the steam-water separator to further remove the water.

[0075] S3, deoxidation and drying process

[0076] After the hydrogen has been dehydrated by the steam-water separator, it enters the deoxidizer. Inside the deoxidizer, the hydrogen reacts with a deoxidizer (such as a copper-based catalyst) to remove oxygen from the hydrogen. The deoxidation process releases a large amount of heat, so the gas exiting the deoxidizer must first be cooled by a hydrogen cooler. The cooled gas then enters the cooling condenser, where it is further cooled with chilled water to remove water. It then enters the hydrogen drying device through its air inlet and then through the vents and air holes into the chamber, where it is further treated with multiple layers of desiccant to remove any residual moisture.

[0077] S4, pressure swing adsorption process

[0078] The cooled gas enters a pressure swing adsorption (PSA) unit. This unit is filled with adsorbents (such as activated alumina, activated carbon, silica gel, and molecular sieves). These adsorbents selectively adsorb nitrogen and small amounts of impurities in the hydrogen. During the adsorption process, the nitrogen and impurities in the hydrogen are adsorbed on the adsorbent, while pure hydrogen flows out through the adsorption bed. By adjusting the pressure and temperature of the adsorption bed, the adsorbent can be regenerated and hydrogen can be produced continuously. Ultimately, hydrogen with a purity exceeding 99.99% can be obtained.

[0079] The examples of this specific embodiment are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, any effective changes made based on the structure, shape, and principle of this application should be included in the scope of protection of this application.

Claims

1. A hydrogen drying device for hydrogen production in the chlor-alkali industry, characterized in that: The invention comprises a main pipeline (1), wherein the main pipeline (1) comprises an "I"-shaped middle piece (13) and two connecting pipes (14); the middle piece (13) comprises two parallel connecting plates (131), and an intermediate plate (132) fixed between the two connecting plates (131); both sides of the intermediate plate (132) form mounting areas (133); the connecting plates (131) on both sides of the mounting areas (133) are provided with a plurality of vent holes (1311); the two connecting pipes (14) correspond to the two connecting plates (131) respectively, and the connecting pipes (14) are fixed to the connecting plates (131); A drying box (2) is slidably connected in the installation area (133), and a plurality of air holes (211) are provided at both ends of the drying box (2). The drying box (2) is connected to the two connecting pipes (14) through the air holes (211) and the vent holes (1311); A plurality of desiccant sheets are arranged at intervals in the drying box (2); A cavity (1313) is provided in the connection plates (131) on both sides of the installation area (133), the cavity (1313) passes through the vent hole (1311), and an operation hole (1314) communicating with the cavity (1313) is provided on one side of the connection plate (131) facing the middle plate (132); A partition plate (3) is slidably connected in the cavity (1313), and the partition plate (3) includes a main body (31) and a force-bearing part (32). The main body (31) is slidably connected to the cavity (1313), and a plurality of connecting holes (311) are provided on the main body (31). The plurality of connecting holes (311) and the plurality of vent holes (1311) are used in a one-to-one correspondence. The force-bearing part (32) passes through the operating hole (1314) and extends into the installation area (133). An elastic member (4) is provided between the force-bearing part (32) and the intermediate plate (132). Under the action of the elastic member (4), the vent holes (1311) are aligned with the connecting holes (311). A locking piece (5) is provided between the drying box (2) and the main pipe (1); after the drying box (2) is installed in the installation area (133), the air hole (211), the vent hole (1311) and the connection hole (311) are aligned, and the drying box (2) is fixed by the locking piece (5); The drying box (2) comprises a box body (21), both ends of the box body (21) are provided with sliding grooves (212) for use with the force-bearing part (32), and the force-bearing part (32) is aligned with the sliding grooves (212); It also includes a pushing member (22) that is slidably connected to the sliding groove (212), and an elastic member (221) is fixedly connected between the pushing member (22) and the drying box (2). Under the action of the elastic member (4), the side of the pushing member (22) facing the middle plate (132) is flush with the side of the drying box (2) facing the middle plate (132). When the box body (21) is installed in the installation area (133), the pushing member (22) presses the force-bearing portion (32) into the hidden groove (1321); A track (213) is provided in the sliding groove (212) along the length direction of the sliding groove (212); a sliding member (24) is slidably connected to the side of the pushing member (22) in the sliding groove (212) away from the middle plate (132); a slider (241) is fixedly connected to the sliding member (24); the slider (241) is slidably connected to the track (213); a hand-held plate (23) is provided on the side of the box (21) away from the middle plate (132); the sliding member (24) is fixedly connected to the hand-held plate (23); a pull rope (25) is fixedly connected between the sliding member (24) and the pushing member (22); When the slider (241) slides to the end of the track (213) away from the middle plate (132), the connection hole (311) on the partition plate (3) and the vent hole (1311) on the connection plate (131) are in a misaligned state.

2. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 1, characterized in that: The elastic member (4) includes a push rod (41) rotatably connected to the intermediate plate (132), and a torsion spring installed between the push rod (41) and the intermediate plate (132).

3. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 1, characterized in that: A hidden groove (1321) is provided on the middle plate (132), the elastic member (4) is located in the hidden groove (1321), and after the drying box (2) is installed in the installation area (133), the force-bearing portion (32) of the partition plate (3) is hidden in the hidden groove (1321).

4. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 1, characterized in that: The locking member (5) is a magnet fixed to the intermediate member (13).

5. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 1, characterized in that: Grooves (1312) are provided on the edges of the connecting plates (131) on both sides of the installation area (133); under the action of the elastic member (221), the handheld plate (23) is attached to the drying box (2), and both sides of the handheld plate (23) extend into the grooves (1312).

6. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 5, characterized in that: A placement groove (214) is provided on one side of the box body (21) facing the handheld plate (23), and a push rod (2141) is hinged in the placement groove (214).

7. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 1, characterized in that: The drying box (2) comprises a body (215) and a cover plate (216); the body (215) is provided with an opening; the cover plate (216) is detachably mounted on the opening of the box body (21); a mounting frame (6) is provided in the body (215); a plurality of tooling areas (61) are provided on the mounting frame (6); a plurality of desiccant sheets correspond to the plurality of tooling areas (61) respectively; the desiccant sheets are slidably connected to the tooling areas (61).

8. A method for recovering hydrogen in the chlor-alkali industry using the drying device according to any one of claims 1 to 7, comprising the following steps: S1, dechlorination process; The gas from the electrolysis process enters the elution tower, where the hydrogen is sprayed and scrubbed with sodium sulfide solution to remove chlorine; S2, raw gas compression process; The hydrogen-containing tail gas with chlorine removed enters the cyclone separator to remove the water carried in the tail gas. The hydrogen compressor pressurizes the tail gas to 0.8MPa. The pressurized hydrogen enters the steam-water separator to remove the water. S3, deoxidation and drying process After the hydrogen is dehydrated by the steam-water separator, it enters the deoxidizer to remove oxygen from the hydrogen. It is then cooled by the hydrogen cooler. The cooled gas then enters the cooling condenser and is further cooled with chilled water to remove water. It then enters the drying device to further remove residual water vapor. S4, pressure swing adsorption process The cooled gas enters the pressure swing adsorption device to adsorb and remove nitrogen and a small amount of impurity gas in the hydrogen.

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