Methanol synthesis reactor, method for methanol synthesis and method for coal-to-methanol

Abstract

The present disclosure relates to a methanol synthesis reactor, which comprises a reactor body and a plurality of reaction tubes, the reactor body is provided with a gas inlet for feeding mixed gas into the inner cavity of the reactor body, the mixed gas contains carbon monoxide and carbon dioxide; all the reaction tubes are arranged in and communicated with the inner cavity, the reaction tube is formed with an inner tube reaction zone and an outer tube reaction zone, the inner tube reaction zone is isolated from the outer tube reaction zone by a separation film; the inner part of one of the inner tube reaction zone and the outer tube reaction zone is filled with a first methanol catalyst for eliminating carbon monoxide, and the inner part of the other is filled with a second methanol catalyst for eliminating carbon dioxide, the separation film can pass carbon monoxide or carbon dioxide, so that carbon monoxide or carbon dioxide moves in the reaction tube according to the gas concentration difference in the inner tube reaction zone and the outer tube reaction zone, so as to realize the zoned reaction of carbon monoxide and carbon dioxide, realize the common reaction in the same reactor, and realize the high-efficiency methanol synthesis.

Description

Technical Field

[0001] This disclosure relates to the field of coal gasification technology, and in particular to a methanol synthesis reactor, a method for methanol synthesis, and a method for producing methanol from coal. Background Technology

[0002] Methanol is an important organic chemical raw material, widely used in formaldehyde, ethanol, acetic acid, methyl tert-butyl ether, pharmaceuticals, and pesticides. Currently, all of my country's methanol production capacity uses coal as raw material, and the process includes coal gasification to produce syngas, syngas shift conversion and decarbonization, and methanol synthesis.

[0003] In addition to the effective gases carbon monoxide and hydrogen, the coal gasification process inevitably produces a large amount of carbon dioxide waste gas. Since carbon monoxide and carbon dioxide have different reactivity, if they react in the same reactor, their reactions will restrict each other, making it impossible to achieve efficient methanol synthesis from carbon monoxide and carbon dioxide in the same reactor. Summary of the Invention

[0004] To solve the above-mentioned technical problems, or at least partially solve them, this disclosure provides a methanol synthesis reactor, a method for methanol synthesis, and a method for coal-to-methanol production.

[0005] In a first aspect, this disclosure provides a methanol synthesis reactor, which includes a reactor body and several reaction tubes. The reactor body has an inlet for a mixed gas to enter, and the mixed gas contains carbon monoxide and carbon dioxide.

[0006] All reaction tubes are located in and connected to the inner cavity of the reactor body. An inner tube reaction zone and an outer tube reaction zone are formed inside the reaction tube. One of the inner tube reaction zone and the outer tube reaction zone is filled with a first methanol catalyst for eliminating carbon monoxide, and the other of the inner tube reaction zone and the outer tube reaction zone is filled with a second methanol catalyst for eliminating carbon dioxide.

[0007] The inner tube reaction zone and the outer tube reaction zone are separated by a separation membrane, which allows carbon monoxide or carbon dioxide to pass through. This allows carbon monoxide or carbon dioxide to move directionally within the reaction tube due to the gas concentration difference between the inner and outer tube reaction zones, enabling carbon monoxide and carbon dioxide to undergo a zoned reaction to produce methanol.

[0008] Optionally, a separation membrane support is coaxially arranged inside the reaction tube, and the separation membrane support is located between the reaction zone of the inner tube and the reaction zone of the outer tube, with the separation membrane wrapped around the outer wall of the separation membrane support.

[0009] Optionally, a separation sleeve is also provided inside the reaction tube. The separation sleeve is located at the bottom end of the separation membrane support and is coaxially connected to the separation membrane support. The inner tube reaction zone and the outer tube reaction zone are separated from each other by the separation sleeve on one side of the bottom of the reaction tube.

[0010] Optionally, a base support structure is provided at the bottom opening of the reaction tube, and the outer edge of the base support structure is connected to the edge of the bottom opening of the reaction tube. The separation sleeve is supported inside the reaction tube by the base support structure.

[0011] Optionally, in the axial direction of the reaction tube, the length of the separation membrane is 1 / 2 to 9 / 10 of the length of the reaction tube.

[0012] Optionally, the reactor body includes an upper head, a lower head, and a vessel body. The vessel body is a barrel-shaped structure with openings at both the upper and lower ends. The upper head and the lower head are respectively placed over the openings at the upper and lower ends of the vessel body, and the reaction tube is located inside the vessel body.

[0013] An air inlet is formed on the upper end cap, and a discharge outlet is formed on the lower end cap, so that the reaction products inside the reactor body can be discharged through the discharge outlet.

[0014] Optionally, the discharge port includes a first discharge port and a second discharge port. The bottom opening of the inner tube reaction zone is connected to the first discharge port so that the reaction products in the inner tube reaction zone are discharged through the first discharge port. The bottom opening of the outer tube reaction zone is connected to the second discharge port so that the reaction products in the outer tube reaction zone are discharged through the second discharge port.

[0015] Optionally, a collecting pipe is also provided at the bottom of the reactor body. The inlet end of the collecting pipe is connected to the bottom opening of each inner tube reaction zone, and the outlet end of the collecting pipe is connected to the first discharge port.

[0016] Optionally, a separation membrane support and a separation sleeve are coaxially arranged inside the reaction tube. The separation membrane support is located between the inner tube reaction zone and the outer tube reaction zone. The separation membrane is wrapped around the outer wall of the separation membrane support. The separation sleeve is at the bottom end of the separation membrane support and is coaxially connected to the separation membrane support. The inner tube reaction zone and the outer tube reaction zone are separated from each other by the separation sleeve on one side of the bottom of the reaction tube.

[0017] The bottom of the separating sleeve is connected to the inlet end of the collecting pipe.

[0018] Optionally, several cooling water baffles are arranged vertically in the inner cavity, and water passages are formed between the cooling water baffles and the inner wall of the reactor body.

[0019] All water inlets are staggered along the axial direction of the reaction tube.

[0020] Optionally, at least one fixing plate is provided laterally in the inner cavity, and the surface of the fixing plate is provided with several fixing holes, into which the reaction tube is inserted.

[0021] Secondly, this disclosure also provides a method for methanol synthesis using the aforementioned methanol synthesis reactor, comprising:

[0022] A mixed gas containing carbon monoxide and carbon dioxide is introduced into the inner cavity of the reactor body.

[0023] The mixed gas is introduced into the reaction tube, so that carbon monoxide or carbon dioxide moves directionally between the inner tube reaction zone and the outer tube reaction zone of the reaction tube to produce methanol through a zoned reaction.

[0024] Thirdly, this disclosure also provides a method for producing methanol from coal using the aforementioned methanol synthesis reactor, comprising:

[0025] Coal is gasified to produce crude syngas containing carbon monoxide and carbon dioxide.

[0026] The crude syngas is purified and desulfurized, and then mixed with green hydrogen to form a mixed gas.

[0027] The mixed gas is introduced into the inner cavity of the reactor body;

[0028] The mixed gas is introduced into the reaction tube, so that carbon monoxide or carbon dioxide moves directionally between the inner tube reaction zone and the outer tube reaction zone of the reaction tube to produce methanol through a zoned reaction.

[0029] The technical solution provided in this disclosure has the following advantages compared with the prior art:

[0030] The methanol synthesis reactor, methanol synthesis method, and coal-to-methanol method disclosed herein improve the reactor by incorporating a reaction tube and dividing the reaction tube into zones using a separation membrane. Methanol catalysts targeting carbon monoxide and carbon dioxide are placed in different zones. Since the separation membrane allows both carbon monoxide and carbon dioxide to pass through, the mixed gas, after being introduced into the reaction tube, undergoes catalytic reactions under the action of the catalysts. As the concentrations of carbon monoxide and carbon dioxide gradually decrease during the reaction, the gas in the zone with the higher concentration passes through the separation membrane to continue the reaction. This achieves both zoned reactions and simultaneous reactions within the same reactor, enabling highly efficient methanol synthesis from carbon monoxide and carbon dioxide. Attached Figure Description

[0031] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0032] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the methanol synthesis reactor described in Embodiment 1 of this disclosure;

[0034] Figure 2 This is a schematic diagram of the structure of the separation membrane support described in Embodiment 1 of this disclosure;

[0035] Figure 3 This is a schematic diagram of the internal structure of the reaction tube described in Embodiment 1 of this disclosure;

[0036] Figure 4 for Figure 3 A partial structural diagram of part A in the middle;

[0037] Figure 5 This is a schematic flowchart of the methanol synthesis method described in Embodiment 2 of this disclosure;

[0038] Figure 6 This is a schematic flowchart of the coal-to-methanol method described in Embodiment 3 of this disclosure.

[0039] The components are as follows: 1. Reactor body; 11. Air inlet; 12. Upper head; 13. Lower head; 14. Reactor body; 15. First discharge port; 16. Second discharge port; 17. Cooling water inlet; 18. Cooling water outlet; 19. Cooling water baffle; 2. Reaction tube; 21. Inner tube reaction zone; 22. Outer tube reaction zone; 23. First methanol catalyst; 24. Second methanol catalyst; 25. Separation membrane; 26. Separation membrane support; 261. Support frame; 262. Support beam; 27. Bottom support structure; 28. Separation sleeve; 3. Collecting pipe; 4. Fixed orifice plate. Detailed Implementation

[0040] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0041] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0042] Methanol is an important organic chemical raw material, widely used in formaldehyde, ethanol, acetic acid, methyl tert-butyl ether, pharmaceuticals, and pesticides. In recent years, the application areas of methanol have been continuously expanding, and its demand is also constantly increasing, indicating a promising future for the development of the methanol industry.

[0043] Currently, all of my country's methanol production capacity uses coal as raw material, and the process includes coal gasification to produce syngas, syngas shift decarbonization, and methanol synthesis.

[0044] In addition to the effective gases carbon monoxide and hydrogen, the coal gasification process inevitably produces a large amount of carbon dioxide. Carbon dioxide and the carbon dioxide produced in subsequent conversion processes must be removed during the decarbonization process. If they are directly emitted into the atmosphere, the resulting greenhouse effect and the resulting changes in the ecological climate threaten human survival.

[0045] For the coal-to-methanol industry, due to the different reactivity of carbon monoxide and carbon dioxide, if they react in the same reactor, their reactions will not only mutually restrict each other—carbon monoxide reacts faster, causing carbon dioxide to be carried out of the reactor before it can react, but the presence of carbon dioxide will also reduce the partial pressure of carbon monoxide, leading to a slower reaction rate—but also, the carbon dioxide reaction produces water, which will slowly pulverize the carbon monoxide-to-methanol catalyst (currently commonly copper-zinc-aluminum catalysts, with aluminum as a co-aluminum catalyst pulverizing upon contact with water), reducing its catalytic activity. Therefore, it is currently impossible to achieve efficient methanol synthesis from carbon monoxide and carbon dioxide in the same reactor.

[0046] To address the aforementioned shortcomings, this embodiment provides a methanol synthesis reactor. By improving the reactor body, it achieves zoned reactions of carbon monoxide and carbon dioxide within the reactor body, and its structure is simple and easy to set up. Specifically, the structural configuration of this methanol synthesis reactor is as follows:

[0047] Example 1

[0048] like Figure 1-4 As shown, this embodiment provides a methanol synthesis reactor, which includes a reactor body 1 and several reaction tubes 2. The reactor body 1 is provided with an inlet 11 for introducing a mixed gas into the inner cavity of the reactor body 1. The mixed gas contains carbon monoxide and carbon dioxide.

[0049] This methanol synthesis reactor is used in the coal gasification process. Typically, the crude synthesis gas produced by coal gasification, after initial purification to remove ash, directly enters the desulfurization system for desulfurization. The desulfurized synthesis gas is then mixed with green hydrogen to adjust the hydrogen-to-carbon ratio to between 3 and 5. This adjusted synthesis mixture then enters the methanol synthesis reactor, where the methanol synthesis reaction takes place. Adjusting the hydrogen-to-carbon ratio is crucial for optimal reaction performance, preventing either an excessively low ratio (leading to incomplete reaction) or an excessively high ratio (increasing hydrogen circulation energy consumption).

[0050] All reaction tubes 2 are located inside and connected to the inner cavity of the reactor body 1. An inner tube reaction zone 21 and an outer tube reaction zone 22 are formed inside the reaction tube 2. One of the inner tube reaction zone 21 and the outer tube reaction zone 22 is filled with a first catalyst for eliminating carbon monoxide, and the other of the inner tube reaction zone 21 and the outer tube reaction zone 22 is filled with a second catalyst for eliminating carbon dioxide. The inner tube reaction zone 21 and the outer tube reaction zone 22 are separated by a separation membrane 25, which allows carbon monoxide or carbon dioxide to pass through. This allows carbon monoxide or carbon dioxide to move directionally within the reaction tube 2 according to the gas concentration difference between the inner tube reaction zone 21 and the outer tube reaction zone 22, so as to carry out a zoned reaction of carbon monoxide and carbon dioxide to produce methanol.

[0051] In practice, the mixed gas is introduced into the methanol synthesis reactor, and carbon monoxide and carbon dioxide react separately in reaction tube 2. Since the inner tube reaction zone 21 and the outer tube reaction zone 22 are equipped with different reaction catalysts, only one type of gas can react in a single reaction zone.

[0052] Because carbon monoxide is highly reactive, it rapidly reacts with hydrogen in the reaction tube 2 under the action of the first methanol catalyst 23 to synthesize methanol. As carbon monoxide is continuously consumed, the carbon dioxide concentration in the reaction zone where the first methanol catalyst 23 is placed gradually increases. For example, when the separation membrane 25 has the best permeation effect on carbon dioxide, carbon dioxide in the reaction zone where the first methanol catalyst 23 is placed passes through the separation membrane 25 and enters another reaction zone through the selective permeation effect of the separation membrane 25. At the same time, the unconsumed residual hydrogen passes through the separation membrane 25 and enters another reaction zone, thereby causing carbon dioxide to react and generate methanol and water.

[0053] The product after the reaction flows directly out from the bottom of reaction tube 2 and enters the crude alcohol distillation system in the next step. The unreacted gaseous product flows back to the reactor inlet through the outlet at the top of the reactor, and after adjusting the hydrogen-carbon ratio with green hydrogen, it re-enters the reactor to participate in the synthesis reaction until it is completely consumed.

[0054] This methanol synthesis reactor is an improvement that incorporates a reaction tube 2 inside the reactor. The reaction tube 2 is divided into sections by a separation membrane 25, with methanol catalysts for carbon monoxide and carbon dioxide placed in each section. Since the separation membrane 25 allows both carbon monoxide and carbon dioxide to pass through, the mixed gas, after being introduced into the reaction tube 2, undergoes catalytic reactions under the action of the catalysts. As the concentrations of carbon monoxide and carbon dioxide gradually decrease during the reaction, the gas in the section with the higher concentration passes through the separation membrane 25 to continue reacting. This not only achieves zoned reactions but also enables simultaneous reactions within the same reactor, achieving highly efficient methanol synthesis from carbon monoxide and carbon dioxide.

[0055] In this embodiment, the separation membrane 25 is used as an example to illustrate the best permeation effect of carbon monoxide. In other embodiments, the membrane can be replaced accordingly, or the separation membrane 25 can be made to have a good permeation effect for both gases, as long as the reaction is carried out in sections and at least one of the gases can pass through the separation membrane 25 smoothly.

[0056] In this embodiment, the separation membrane 25 is an organic or inorganic membrane capable of efficiently separating carbon monoxide and carbon dioxide, such as a molecular sieve membrane, a nano-graphene oxide membrane, a hollow fiber membrane, a polyethylene membrane, a polypropylene membrane, a polytetrafluoroethylene membrane, or a polysulfone ether membrane. The first methanol catalyst 23 for reacting with carbon monoxide is copper-zinc-aluminum oxide, and the second methanol catalyst 24 for reacting with carbon dioxide can be copper-zinc-aluminum oxide.

[0057] Meanwhile, to increase the driving force of carbon monoxide permeation, the pressure difference between the inner tube reaction zone 21 and the outer tube reaction zone 22 can be controlled at 0.05-0.5 MPa. This is to avoid insufficient driving force for permeation due to a small pressure difference, which would prevent effective separation of carbon dioxide and carbon monoxide, or excessive pressure difference, which would result in a greater impact on the separation membrane 25 and increase the risk of damaging the separation membrane 25.

[0058] The reactor body 1 includes an upper end cap 12, a lower end cap 13, and a vessel body 14. The vessel body 14 is a barrel-shaped structure with openings at both the top and bottom. The upper end cap 12 and the lower end cap 13 are respectively installed at the openings at the top and bottom of the vessel body 14. The reaction tube 2 is located inside the vessel body 14. (See details...) Figure 1 As shown.

[0059] The upper head 12 and lower head 13 are bucket-lid structures, used to create a closed area inside the reactor body 1 and to provide necessary openings for operations such as feeding, water intake, and air intake. A connecting flange is provided on the bottom edge of the upper head 12, and correspondingly, a connecting flange is also provided at the top opening of the reactor body 14, thereby connecting the upper head 12 and the reactor body 14 via flanges. A sealing structure can be provided at the connection point to ensure a tight seal inside the reactor body 1. The connection method between the lower head 13 and the reactor body 14 can be the same as that between the upper head 12 and the reactor body 14.

[0060] Furthermore, an air inlet 11 is formed on the upper head 12, and a discharge port is formed on the lower head 13, so that the reaction products inside the reactor body 1 can be discharged through the discharge port. Correspondingly, the inlet of the reaction pipe 2 faces the air inlet 11 located on the upper head 12 to facilitate the smooth entry of the mixed gas, and the outlet of the reaction pipe 2 faces the discharge port to facilitate the smooth discharge of the reaction products.

[0061] For the discharge port provided on the lower end cap 13, since there are two reaction zones and the reaction products of carbon dioxide and carbon monoxide hydrogenation to synthesize methanol are different, corresponding discharge ports also need to be provided, so that the discharge ports include a first discharge port 15 and a second discharge port 16. The bottom opening of the inner tube reaction zone 21 is connected to the first discharge port 15 so that the reaction products in the inner tube reaction zone 21 are discharged through the first discharge port 15; the bottom opening of the outer tube reaction zone 22 is connected to the second discharge port 16 so that the reaction products in the outer tube reaction zone 22 are discharged through the second discharge port 16.

[0062] Based on this, to facilitate the discharge of products from the inner tube reaction zone 21 from the first outlet 15 and products from the outer tube reaction zone 22 from the second outlet 16, a collecting pipe 3 can be installed at the outlet end of the inner tube reaction zone 21. The inlet end of the collecting pipe 3 is connected to the bottom opening of each inner tube reaction zone 21, and the outlet end of the collecting pipe 3 is connected to the first outlet 15. Through the collecting effect of the collecting pipe 3, all products in the inner tube reaction zone 21 are guided to the first outlet 15, thereby achieving a diversion effect between the inner tube reaction zone 21 and the outer tube reaction zone 22.

[0063] In this embodiment, the first discharge port 15 is located on the side wall of the lower end cap 13, and the second discharge port 16 is located at the bottom of the lower end cap 13, thus placing the two discharge positions a certain distance apart to facilitate subsequent collection. Furthermore, and more importantly, for the inner tube reaction zone 21, discharging its products through the collecting pipe 3 via the side of the lower end cap 13 also prevents the high-pressure products from the inner tube from flowing back into the outer tube channel through the space of the lower end cap 13. Of course, in other embodiments, the location of the discharge ports can be adjusted adaptively, as long as the diversion effect is not affected.

[0064] Based on the aforementioned structural design of the reactor body 1, to facilitate the installation of the reaction tube 2 within the reactor body 1, at least one fixing plate 4 can be laterally arranged in the inner cavity of the reactor body 1. The surface of the fixing plate 4 has several fixing holes, into which the reaction tube 2 is inserted. The fixing plate 4 limits the position of the reaction vessel, providing support and ensuring it is positioned optimally within the reactor body 1, thus facilitating the reaction process within the reaction tube 2. In this embodiment, two fixing plates 4 are provided, located at the upper and lower openings of the reactor body 14 respectively, thereby securing the reaction tube 2 at both ends to ensure a secure fixation and stability during use.

[0065] In this embodiment, multiple reaction tubes 2 are arranged inside the reactor body 1, extending vertically and parallel to each other. The vertical extension of the reaction tubes 2 facilitates their alignment with the air inlet 11 at the upper end cap 12 and the discharge outlet at the lower end cap 13. The reaction tubes 2 can be evenly distributed within the reactor body 1 to ensure that the distance between each reaction tube 2 is the same, thus ensuring a balanced reaction process within each reaction tube 2. Furthermore, to ensure that the reaction tubes 2 can maintain a suitable reaction temperature, the distance between adjacent reaction tubes 2 must not be less than half the diameter of the reaction tube 2.

[0066] After determining the connection method between the reaction tube 2 and the reactor body 1, a separation membrane support 26 can be coaxially arranged inside the reaction tube 2. The separation membrane support 26 is located between the inner tube reaction zone 21 and the outer tube reaction zone 22, and the separation membrane 25 is wrapped around the outer wall of the separation membrane support 26. Through the combination of the separation membrane support 26 and the separation membrane, the inner area of ​​the separation membrane support 26 forms the inner tube reaction zone 21, and the area between the separation membrane support 26 and the reaction tube 2 forms the outer tube reaction zone 22. The separation membrane support 26 provides a supporting structure for the separation membrane 25, allowing it to maintain a fixed shape within the reaction tube 2. Furthermore, the coaxial arrangement of the separation membrane support 26 with the reaction tube 2 creates a more balanced reaction space, and the annular arrangement facilitates the passage of gas through the separation membrane 25 into another reaction zone, which helps to increase reaction efficiency.

[0067] like Figure 2As shown, the separation membrane support 26 can use a frame structure to minimize its area while ensuring support for the separation membrane 25. For example, the separation membrane support 26 may include several support frames 261 and several support beams 262. The support frames 261 have the same cross-sectional shape as the reaction tube 2 and are smaller than the cross-section of the reaction tube 2, so that an outer tube reaction zone 22 is formed between the separation membrane support 26 and the reaction tube 2. The several support frames 261 are distributed along the axial direction and fixed in multiple places by the support beams 262, thereby forming a relatively stable separation membrane support 26.

[0068] Based on this, a base support structure 27 is provided at the bottom opening of the reaction tube 2. The outer edge of the base support structure 27 is connected to the edge of the bottom opening of the reaction tube 2, and the separation membrane support 26 is supported inside the reaction tube 2 through the base support structure 27. The base support structure 27 supports the separation membrane support 26 on the one hand, and on the other hand, it also supports the catalyst bed inside the reaction tube 2. The base support structure 27 can be made of dense metal mesh or other metal structures that can be made into a catalyst bed, so that it can support the catalyst and the separation membrane support 26 without affecting the discharge of products.

[0069] During the hydrogenation of carbon dioxide to methanol, water is inevitably generated in addition to the main product, methanol. This water tends to flow downwards along the catalyst bed and accumulate at the bottom of reaction tube 2. To prevent water accumulation at the bottom of reaction tube 2 from soaking and damaging the separation membrane 25, thus connecting the inner and outer tube reaction zones 22, a separation sleeve 28 is installed inside reaction tube 2. The separation sleeve 28 is coaxially positioned on one side of the bottom of reaction tube 2 and connected to the bottom end of the separation membrane support 26. The inner tube reaction zone 21 and the outer tube reaction zone 22 are separated from each other on one side of the bottom of reaction tube 2 by the separation sleeve 28.

[0070] The axial length of the separation membrane 25 and the separation membrane support 26 is less than the length of the reaction tube 2. The top of the separation membrane support 26 is flush with the top of the reaction tube 2. To balance the effective separation efficiency of the separation membrane 25 and the impact of the accumulated water height at the bottom on the lifespan and strength of the separation membrane 25, the relationship between the length D1 of the separation membrane 25 and the length D2 of the reaction tube 2 is 0.5D2≤D1≤0.9D2. The bottom of the separation membrane support 26 is connected to the separation sleeve 28, which is coaxially connected to the bottom of the separation membrane support 26. The bottom of the separation sleeve 28 is supported at the bottom of the reaction tube 2 by the bottom support structure 27. The bottom of the separation sleeve 28 passes through the fixed orifice plate 4 and extends to the area of ​​the lower end cap 13 to communicate with the collecting pipe 3, thereby allowing the collecting pipe 3 to drain the product from the inner tube reaction zone 21.

[0071] In addition, to cool the reaction tube 2 during the reaction process, a cooling water inlet 17 is provided at the bottom of the reactor body 1, and a cooling water outlet 18 is provided at the top of the reactor body 1. The cooling water inlet 17 is used to introduce cooling water into the inner cavity to cool the reaction tube 2. By introducing cooling water, heat exchange is performed on the reaction tube 2, and the water that has absorbed heat is discharged from the top, thereby achieving the effect of removing heat from the reaction tube 2.

[0072] Furthermore, to enhance cooling and heat exchange capacity, several cooling water baffles 19 are arranged vertically within the inner cavity, forming water passages between the cooling water baffles 19 and the inner wall of the reactor body 1. All water passages are staggered along the axial direction of the reaction tube 2. This staggered arrangement of the water passages increases the flow path length of the cooling water, extending the heat exchange process time and further improving the heat exchange effect.

[0073] Example 2

[0074] like Figure 5 As shown, this embodiment provides a method for methanol synthesis, which uses the methanol synthesis reactor in Embodiment 1 to synthesize methanol. The methanol synthesis method specifically includes the following steps:

[0075] Step 101: Introduce a mixed gas containing carbon monoxide and carbon dioxide into the inner cavity of the reactor body;

[0076] Step 102: Allow the mixed gas to enter the reaction tube so that carbon monoxide or carbon dioxide can move directionally between the inner tube reaction zone and the outer tube reaction zone of the reaction tube to produce methanol through a zoned reaction.

[0077] The mixed gas is typically a gas containing carbon monoxide and carbon dioxide, formed by processing the crude syngas produced from coal gasification. In other embodiments, the mixed gas containing carbon monoxide and carbon dioxide obtained by other means can also be subjected to methanol synthesis processing.

[0078] In addition, to increase the driving force of carbon monoxide permeation, the pressure difference between the inner tube reaction zone and the outer tube reaction zone can be controlled at 0.05-0.5 MPa. This is to avoid insufficient driving force for permeation due to a small pressure difference, which would prevent effective separation of carbon dioxide and carbon monoxide, or excessive pressure difference, which would result in a greater impact on the separation membrane and increase the risk of damaging the separation membrane.

[0079] Example 3

[0080] like Figure 6 As shown, this embodiment provides a method for producing methanol from coal, which uses the methanol synthesis reactor from Embodiment 1 to synthesize methanol. The specific steps of this coal-to-methanol method are as follows:

[0081] Step 201: Gasify the coal to produce crude syngas containing carbon monoxide and carbon dioxide;

[0082] Step 202: Purify and desulfurize the crude syngas, and mix it with green hydrogen to form a mixed gas;

[0083] Step 203: Introduce the mixed gas into the inner cavity of the reactor body;

[0084] Step 204: Allow the mixed gas to enter the reaction tube so that carbon monoxide or carbon dioxide can move directionally between the inner tube reaction zone and the outer tube reaction zone to produce methanol through a zoned reaction.

[0085] In step 202, the crude syngas is purified and desulfurized. Specifically, after initial purification to remove ash, it is directly introduced into the desulfurization system for desulfurization. The treated crude syngas is then mixed with green hydrogen, and the hydrogen-to-carbon ratio after mixing needs to be between 3 and 5 before entering the methanol synthesis reactor. This improves the reaction effect and avoids incomplete reaction due to an excessively low hydrogen-to-carbon ratio, or increased hydrogen circulation energy consumption due to an excessively high hydrogen-to-carbon ratio.

[0086] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0087] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A methanol synthesis reactor, characterized in that, It includes a reactor body (1) and several reaction tubes (2). The reactor body (1) is provided with an air inlet (11) for the mixed gas to enter. The mixed gas contains carbon monoxide and carbon dioxide. All of the reaction tubes (2) are disposed in the inner cavity of the reactor body (1) and communicate with the inner cavity. An inner tube reaction zone (21) and an outer tube reaction zone (22) are formed in the reaction tube (2). The interior of one of the inner tube reaction zone (21) and the outer tube reaction zone (22) is filled with a first methanol catalyst (23) for eliminating carbon monoxide. The interior of the other of the inner tube reaction zone (21) and the outer tube reaction zone (22) is filled with a second methanol catalyst (24) for eliminating carbon dioxide. The inner tube reaction zone (21) and the outer tube reaction zone (22) are separated by a separation membrane (25), and the separation membrane (25) allows carbon monoxide or carbon dioxide to pass through, so that carbon monoxide or carbon dioxide moves directionally in the reaction tube (2) under the action of the gas concentration difference in the inner tube reaction zone (21) and the outer tube reaction zone (22), so that carbon monoxide and carbon dioxide can undergo a zoned reaction to produce methanol; A separation membrane support (26) is coaxially arranged inside the reaction tube (2). The separation membrane support (26) is located between the inner tube reaction zone (21) and the outer tube reaction zone (22). The separation membrane (25) is wrapped around the outer wall of the separation membrane support (26). The reaction tube (2) is also provided with a separation sleeve (28). The separation sleeve (28) is located at the bottom end of the separation membrane support (26) and is coaxially connected to the separation membrane support (26). The inner tube reaction zone (21) and the outer tube reaction zone (22) are separated from each other by the separation sleeve (28) on one side of the bottom of the reaction tube (2). The bottom opening of the reaction tube (2) is provided with a base support structure (27), the outer edge of the base support structure (27) is connected to the edge of the bottom opening of the reaction tube (2), and the separation sleeve (28) is supported at the bottom of the reaction tube (2) by the base support structure (27).

2. The methanol synthesis reactor according to claim 1, characterized in that, In the axial direction of the reaction tube (2), the length of the separation membrane (25) is 1 / 2 to 9 / 10 of the length of the reaction tube (2).

3. The methanol synthesis reactor according to any one of claims 1-2, characterized in that, The reactor body (1) includes an upper end cap (12), a lower end cap (13) and a vessel body (14). The vessel body (14) is a barrel-shaped structure with openings at both the upper and lower ends. The upper end cap (12) and the lower end cap (13) are respectively covered at the openings at the upper and lower ends of the vessel body (14). The reaction tube (2) is located inside the vessel body (14). The air inlet (11) is formed on the upper end cap (12), and the discharge port is formed on the lower end cap (13) so that the reaction products in the reactor body (1) are discharged through the discharge port.

4. The methanol synthesis reactor according to claim 3, characterized in that, The discharge port includes a first discharge port (15) and a second discharge port (16). The bottom opening of the inner tube reaction zone (21) is connected to the first discharge port (15) so that the reaction products in the inner tube reaction zone (21) are discharged through the first discharge port (15). The bottom opening of the outer tube reaction zone (22) is connected to the second discharge port (16) so that the reaction products in the outer tube reaction zone (22) are discharged through the second discharge port (16).

5. The methanol synthesis reactor according to claim 4, characterized in that, The bottom of the reactor body (1) is also provided with a collecting pipe (3), the inlet end of the collecting pipe (3) is connected to the bottom opening of each inner tube reaction zone (21), and the outlet end of the collecting pipe (3) is connected to the first discharge port (15).

6. The methanol synthesis reactor according to claim 5, characterized in that, The reaction tube (2) is coaxially provided with a separation membrane support (26) and a separation sleeve (28). The separation membrane support (26) is located between the inner tube reaction zone (21) and the outer tube reaction zone (22). The separation membrane (25) is wrapped around the outer wall of the separation membrane support (26). The separation sleeve (28) is located at the bottom end of the separation membrane support (26) and is coaxially connected to the separation membrane support (26). The inner tube reaction zone (21) and the outer tube reaction zone (22) are mutually blocked on one side of the bottom of the reaction tube (2) by the separation sleeve (28). The bottom of the separating sleeve (28) is connected to the inlet end of the collecting pipe (3).

7. The methanol synthesis reactor according to claim 1, characterized in that, Several cooling water baffles (19) are arranged vertically in the inner cavity, and water inlets are formed between the cooling water baffles (19) and the inner wall of the reactor body (1). All the water inlets are arranged alternately along the axial direction of the reaction tube (2).

8. The methanol synthesis reactor according to claim 1, characterized in that, At least one fixing plate (4) is arranged laterally in the inner cavity. The surface of the fixing plate (4) is provided with several fixing holes, and the reaction tube (2) is inserted into the fixing holes accordingly.

9. A method for methanol synthesis using a methanol synthesis reactor as described in any one of claims 1-8, characterized in that, The method includes: The mixed gas containing carbon monoxide and carbon dioxide is introduced into the inner cavity of the reactor body; The mixed gas is introduced into the reaction tube to allow carbon monoxide or carbon dioxide to move directionally between the inner tube reaction zone and the outer tube reaction zone of the reaction tube to produce methanol through a zoned reaction.

10. A method for producing methanol from coal using a methanol synthesis reactor as described in any one of claims 1-8, characterized in that, The method includes: Coal is gasified to produce crude syngas containing carbon monoxide and carbon dioxide. The crude syngas is purified and desulfurized, and then mixed with green hydrogen to form the mixed gas. The mixed gas is introduced into the inner cavity of the reactor body; The mixed gas is introduced into the reaction tube to allow carbon monoxide or carbon dioxide to move directionally between the inner tube reaction zone and the outer tube reaction zone of the reaction tube to produce methanol through a zoned reaction.

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