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

Abstract

The invention relates to a hydrogen drying device for hydrogen production in the chlor-alkali industry and a hydrogen recovery method. The hydrogen drying device comprises a main pipeline, and the main pipeline comprises an I-shaped middleware and two communicating pipes; the middle piece comprises two connecting plates arranged in parallel and a middle plate fixed between the two connecting plates, mounting areas are formed on the two sides of the middle plate, a plurality of vent holes are formed in the connecting plates on the two sides of the mounting areas, the two communicating pipes correspond to the two connecting plates one to one, and the two communicating pipes are communicated with the two connecting plates. The communicating pipe is fixedly connected to the connecting plate; a drying box is slidably connected into the mounting area, a plurality of air passing holes are formed in the two ends of the drying box, and the drying box communicates with the two communicating pipes through the air passing holes and the vent holes; a plurality of drying agent pieces are arranged in the drying box at intervals. Through the arrangement, the drying agent can be conveniently replaced.

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 an important part of the chemical industry. The chlor-alkali industry is mainly used to produce basic chemicals such as chlorine, hydrogen and caustic soda (sodium hydroxide). Its products have a wide range of uses and an important strategic position in the national economy. With the development of new energy in my country, hydrogen as a high-quality new energy has become increasingly important. The waste gas generated in the chlor-alkali industry contains abundant hydrogen, and the utilization of this part of hydrogen is particularly critical. In the current hydrogen recovery process, it is necessary to separate the water vapor in the gas. The commonly used method is condensation, that is, the purified hydrogen is discharged into the condensation tank for water vapor separation. In order to ensure the purity of the hydrogen, after the hydrogen is discharged from the condensation tank, it is generally poured into the equipment equipped with desiccant for final drying. At present, the desiccant needs to be replaced after a period of use, and the replacement of the desiccant is relatively 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, including a main pipeline, the main pipeline includes an "I"-shaped middle piece and two connecting pipes; the middle piece includes 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, the two connecting pipes correspond to the two connecting plates one by one, and the connecting pipes are fixed to the connecting plates; 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 with the two connecting pipes through the air holes and the vent holes; A plurality of desiccant sheets are arranged at intervals in the drying box.

[0004] By adopting the above solution, when the desiccant sheet in the drying box needs to be replaced after a long period of use, the drying box can be slid out of the installation area for replacement, and in this process, due to the presence of two drying boxes, the main pipeline can always be kept unobstructed, thereby improving the hydrogen production efficiency. Furthermore, cavities are provided in the connection plates on both sides of the installation area, the cavities pass through the vents, and an operation hole connected to the cavity is provided on one side of the connection plate facing the middle plate; 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 connection holes are provided on the main body. The connection holes are used in a one-to-one correspondence with the ventilation 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 middle plate. Under the action of the elastic member, the ventilation holes are aligned with the connection holes. A locking piece is arranged 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.

[0005] By adopting the above solution, after the drying box is installed in the installation area, the drying box presses the force-bearing part, so that the connection hole on the partition plate is connected with the vent hole, and 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 the limit of the drying box. At this time, the partition plate moves away from the middle plate under the action of the elastic member, so that the connection hole and the vent hole are misaligned. At this time, the vent hole is closed, and gas leakage is avoided as much as possible during the process of replacing the desiccant.

[0006] 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.

[0007] 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.

[0008] 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.

[0009] 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.

[0010] 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; It also includes a pushing member slidably connected to the sliding groove, an elastic member is 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 part into the hidden groove; A track is provided in the sliding groove along the length direction of the sliding groove, a sliding member is slidably connected to a side of the pushing member away from the middle plate in the sliding groove, a slider is fixedly connected to the sliding member, the slider is slidably connected to the track, a hand-held board is provided on a side of the box away from the middle plate, the sliding member is fixedly connected to the hand-held board, and a pull rope is fixedly connected between the sliding member and the pushing member; When the sliding block 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.

[0011] By adopting the above scheme, after the box 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. In the process of removing the drying box from the installation area, first pull the hand-held plate to move to the side away from the middle plate. In this process, the hand-held 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, and 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 from the magnet and then from the installation area. In this way, the vent hole is completely closed before the box moves away from the middle plate, avoiding gas leakage as much as possible.

[0012] Furthermore, grooves are provided at the edges of the connection plates on both sides of the installation area. Under the action of the elastic member, the hand-held plate is attached to the drying box, and both sides of the hand-held plate extend into the grooves.

[0013] By adopting the above solution, the sealing performance between the drying box and the main pipeline is further improved.

[0014] Furthermore, a placement groove is provided on a side of the box body facing the hand-held board, and a push rod is hinged in the placement groove.

[0015] By adopting the above scheme, in the process of removing the box body from the installation area, before the box body is separated 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 separated from the magnet, the hand-held 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 in the installation area. In this process, due to the action of the push rod, the vent hole will not open. 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 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 in the installation area as much as possible.

[0016] 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 frame is provided in the main body, a plurality of tooling areas are provided on the mounting frame, a plurality of desiccant sheets correspond one by one to the plurality of tooling areas respectively, and the desiccant sheets are slidably connected to the tooling areas.

[0017] By adopting the above solution, it is convenient to replace the desiccant.

[0018] A method for recovering hydrogen in the chlor-alkali industry using a drying device comprises the following steps: S1, dechlorination process; The gas from the electrolysis process enters the leaching tower, where the hydrogen is sprayed and washed 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, usually to 0.8MPa, and the pressurized hydrogen enters the steam-water separator to remove the water; S3, deoxidation and drying process The hydrogen after dehydration in the steam-water separator 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 the water therein. The gas is then introduced into the hydrogen drying device through the air inlet of the hydrogen drying device. The gas enters the box through the vents and air holes, and the residual water vapor is further removed in the box through the action of multiple layers of desiccant sheets. 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.

[0019] By adopting the above technical solution, high-purity hydrogen can be produced efficiently and quickly.

[0020] In summary, the present invention has at least the following beneficial effects: 1. By setting up two groups of drying ovens, the drying ovens can be replaced alternately, thereby improving the hydrogen production efficiency.

[0021] 2. Through the cooperation of the pusher, the elastic member, the hand-held member and the force-bearing part, after the box 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. In the process of removing the drying box from the installation area, first pull the hand-held plate to move to the side away from the middle plate. In this process, the hand-held 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, and 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 from the magnet and then from the installation area. In this way, the vent hole is completely closed before the box moves away from the middle plate, avoiding gas leakage as much as possible.

[0022] 3. By setting a push rod between the hand-held plate and the box body, in the process of removing the box body from the installation area, before the box body is separated 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 separated from the magnet, the hand-held 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 in the installation area. In this process, due to the action of the push rod, the vent will not open. 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 is attached to the box body under the action of the elastic member, and the vent is opened, so as to avoid gas leakage during the installation of the drying box in the installation area as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram showing the overall structure of the drying device in this embodiment; Figure 2 is a schematic diagram showing the structure of the middleware in this embodiment; Figure 3 is a schematic diagram showing the structure of the drying box in this embodiment; Figure 4 is a schematic diagram showing the internal structure of the connecting plate in this embodiment; Figure 5 yes Figure 4 A partial enlarged schematic diagram of part B; Figure 6 yes Figure 3 A partial enlarged schematic diagram of part A; Figure 7 is a schematic diagram showing the structure of the pusher in the embodiment of the present application; Figure 8 is a schematic diagram showing the arrangement structure of the ejector rod on the drying box in an embodiment of the present application; Fig. 9 yes Figure 8 A partial enlarged schematic diagram of part C in the middle; Fig.10 It is a schematic diagram showing the structure of the mounting frame in the embodiment of the present application.

[0024] Description of reference numerals: 1. Main pipeline; 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 groove; 1322. Mounting groove; 1323. Jack; 1324. Mounting hole; 1325. Screw; 133. Mounting area; 14. Connecting pipe; 2. Drying box; 21. Box body; 211. Air hole; 212. Sliding groove; 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 tablet. DETAILED DESCRIPTION

[0025] 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 fixedly connected 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.

[0026] The drying box 2 is slidably connected in the installation area 133 .

[0027] Reference Figure 3 A 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 with the drying box 2 through the vent holes 1311 and the air holes 211.

[0028] A number of desiccant sheets 611 are evenly arranged in the drying box 2, and the desiccant may be activated carbon or the like.

[0029] When the desiccant sheet 611 in the drying box 2 needs to be replaced after being used for a long time, the drying box 2 can be slid out of the installation area 133 for replacement, and the two drying boxes 2 can be replaced alternately during this process, so that the main pipeline 1 can always be kept unobstructed, thereby improving the hydrogen production efficiency.

[0030] Reference Figure 4 In the process of replacing the desiccant, in order to prevent the gas in the main pipeline 1 from leaking out through the vent holes 1311 as much as possible. The connection plates 131 on both sides of the installation area 133 are provided with cavities 1313, and the cavities 1313 pass through a plurality of vent holes 1311. The connection plates 131 are provided with operation holes 1314 communicating with the cavities 1313 on one side facing the middle plate 132. The cavity 1313 is slidably connected with a partition plate 3, and the partition plate 3 includes an integrally arranged main body 31 and a force-bearing part 32. The main body 31 is slidably connected to the cavity 1313, and a plurality of connection holes 311 are provided on the main body 31. The plurality of connection holes 311 correspond one-to-one with the plurality of vent holes 1311 on the connection plate 131.

[0031] 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 disposed 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.

[0032] Reference Figure 2 There is also a locking member 5 between the drying box 2 and the middle 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 middle 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 part 32, so that the connecting hole 311 on the partition plate 3 is connected with 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 limit of the drying box 2. At this time, the partition plate 3 moves away from the middle plate 132 under the action of the elastic member 4, so that the connecting hole 311 and the vent hole 1311 are misaligned. At this time, the vent hole 1311 is closed to avoid gas leakage during the process of replacing the desiccant as much as possible.

[0033] Reference Figure 4 and Figure 5Specifically, the elastic member 4 includes a push rod 41 with one end hinged to the middle plate 132, a torsion spring is arranged 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.

[0034] In order to make the outer surface of the drying device smoother and increase the utilization area of ​​the connecting plate 131, a hidden groove 1321 for accommodating the elastic member 4 and the partition plate 3 is provided on the middle plate 132. After the drying box 2 is installed in the installation area 133, the side of the drying box 2 facing the middle plate 132 is attached to the middle plate 132, and at this time, the force-bearing portion 32 of the partition plate 3 enters the hidden groove 1321.

[0035] Reference Figure 3 The drying box 2 includes a box body 21, and the end surfaces at 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.

[0036] Reference Figure 6 and Figure 7 The drying box 2 also includes two pushers 22 used in conjunction with the sliding grooves 212. The two pushers 22 correspond to the two sliding grooves 212 one by one. The pushers 22 are slidably connected to the sliding grooves 212, and 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, one 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 installed on the side of the box body 21 away from the middle plate 132. A track 213 is provided in the sliding groove 212. A sliding member 24 is slidably connected to the corresponding sliding groove 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 formed on the sliding member 24 along the length direction of the sliding groove 212 . A pull rope 25 is fixedly connected between the pushing member 22 and the hand-held plate 23 . One end of the pull rope 25 is fixedly connected to the pushing member 22 , and the other end of the pull rope 25 passes through the through hole 242 and is fixedly connected to the hand-held plate 23 .

[0037] After the box body 21 is installed in the installation area 133 , the pusher 22 presses the force-bearing portion 32 into the hidden groove 1321 under the action of the elastic member 221 so that the vent hole 1311 is aligned and connected with the connecting hole 311 . When removing the drying box 2 from the installation area 133, first pull the hand-held plate 23 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 toward 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 toward 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.

[0038] 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 in the installation area 133, the edge of the hand-held plate 23 is located in the groove 1312 under the action of the elastic member 221, further improving the sealing between the drying box 2 and the main pipeline 1.

[0039] Reference Figure 8 and Fig. 9 A layout 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 in the layout groove 214 . When the box 21 is removed from the installation area 133, before the box 21 is separated from the locking piece 5, the free end of the push rod 2141 is rotated to make the free end of the push rod 2141 abut against the hand-held plate 23. 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 be attached to the box 21 due to the action of the elastic member 221. After the desiccant is replaced, the staff will first install 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 attached 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.

[0040] 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.

[0041] Reference Fig.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 to the plurality of tooling areas 61 one by one. The desiccant sheets 611 are slidably connected to the tooling areas 61, so as to facilitate replacement of the desiccant in the box body 21.

[0042] Reference Figure 2 and Figure 3 In order to avoid the drying device 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 used in conjunction 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.

[0043] 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 toward 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, and before the box body 21 is separated from the locking member 5, the free end of the push rod 2141 is rotated so that the free end of the push rod 2141 abuts against the hand-held plate 23, and then the hand-held plate 23 is continued to be pulled to separate the box body 21 from the magnet and then from the installation area 133. In this way, before the box body 21 moves away from the middle plate 132, the vent 1311 is closed. 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 to 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 push rod 2141, the vent 1311 will not open. After the box body 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 attached to the box body 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 into the installation area 133 as much as possible.

[0044] A method for recovering hydrogen in the chlor-alkali industry comprises the following steps: S1, dechlorination process; The gas from the electrolysis process enters the leaching tower, where the hydrogen is sprayed and scrubbed with a sodium sulfide solution. The sodium sulfide solution reacts with the chlorine in the hydrogen to produce sulfide and sodium chloride, thereby removing the 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, usually to 0.8MPa, and the pressurized hydrogen enters the steam-water separator to further remove the water; S3, deoxidation and drying process The hydrogen after dehydration in the steam-water separator enters the deoxidizer. In the deoxidizer, the hydrogen reacts with the deoxidizer (such as a copper-based catalyst) to remove oxygen from the hydrogen. A large amount of heat is released during the deoxidation process, so the gas coming out of the deoxidizer needs to be cooled by a hydrogen cooler first. The cooled gas then enters the cooling condenser and is further cooled with chilled water to remove the water. It then enters the hydrogen drying device through the air inlet of the hydrogen drying device, and then enters the box through the vents and air holes. In the box, the residual water vapor is further removed by the action of multiple layers of desiccant. S4, Pressure Swing Adsorption Process The cooled gas enters the pressure swing adsorption device. The pressure swing adsorption device is filled with adsorbents (such as activated alumina, activated carbon, silica gel, molecular sieves, etc.), which have a selective adsorption effect on nitrogen and a small amount of impurity gas in hydrogen. During the adsorption process, nitrogen and impurity gas in 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 continuously produced. Finally, hydrogen with a purity of more than 99.99% can be obtained.

[0045] The embodiments of this specific implementation are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. The same components are represented by the same figure marks. Therefore, any effective changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present 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 connecting plates (131) arranged in parallel, and an intermediate plate (132) fixed between the two connecting plates (131); both sides of the intermediate plate (132) form a mounting area (133); the connecting plates (131) on both sides of the mounting area (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 fixedly connected to the connecting plates (131); A drying box (2) is slidably connected in the installation area (133), a plurality of air holes (211) are provided at both ends of the drying box (2), and 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 (611) are arranged at intervals in the drying box (2).

2. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 1, characterized in that: The connection plates (131) on both sides of the installation area (133) are provided with cavities (1313), the cavities (1313) pass through the vent holes (1311), and the connection plates (131) are provided with operation holes (1314) in communication with the cavities (1313) on one side facing the middle plate (132); A partition plate (3) is slidably connected in the cavity (1313), and the partition plate (3) comprises a main body (31) and a force-bearing part (32). The main body (31) is slidably connected in the cavity (1313), and a plurality of connection holes (311) are provided on the main body (31), and the plurality of connection holes (311) and the plurality of ventilation 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), and under the action of the elastic member (4), the ventilation holes (1311) are aligned with the connection holes (311); A locking piece (5) is provided between the drying box (2) and the main pipeline (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).

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

4. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 2, 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).

5. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 2, characterized in that: The locking member (5) is a magnet fixed to the intermediate member (13).

6. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 5, characterized in that: 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) slidably connected to the sliding groove (212), an elastic member (221) being fixedly connected between the pushing member (22) and the drying box (2), and under the action of the elastic member (4), a side of the pushing member (22) facing the middle plate (132) is flush with a side of the drying box (2) facing the middle plate (132), and 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 body (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.

7. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 6, characterized in that: Grooves (1312) are provided at the edges of the connecting plates (131) on both sides of the installation area (133); under the action of the elastic member (221), the hand-held plate (23) is attached to the drying box (2), and both sides of the hand-held plate (23) extend into the grooves (1312).

8. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to any one of claim 7, characterized in that: A placement groove (214) is provided on one side of the box body (21) facing the hand-held plate (23), and a push rod (2141) is hinged in the placement groove (214).

9. The hydrogen drying device for hydrogen production in the chlor-alkali industry according to claim 6, 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 arranged inside the body (215); a plurality of tooling areas (61) are arranged on the mounting frame (6); a plurality of desiccant sheets (611) respectively correspond to the plurality of tooling areas (61); and the desiccant sheets (611) are slidably connected to the tooling areas (61).

10. A method for recovering hydrogen in the chlor-alkali industry using the drying device according to any one of claims 1 to 9, 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, usually to 0.8MPa, and the pressurized hydrogen enters the steam-water separator to remove the water; S3, deoxidation and drying process The hydrogen gas after dehydration in the steam-water separator enters the deoxidizer to remove oxygen from the hydrogen gas. It is then cooled by the hydrogen cooler. The cooled gas enters the cooling condenser and is further cooled by chilled water to remove water therein. The gas is then introduced into the hydrogen drying device through the air inlet (11) of the hydrogen drying device. The gas enters the housing (21) through the air vent (1311) and the air hole (211). The residual water vapor is further removed in the housing (21) through the action of the multi-layer desiccant sheet (611). 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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