Methanol preparation system with annular tubular reactor

Abstract

The utility model aims to provide a methanol preparation system with an annular tubular reactor, which relates to the technical field of chemical production and comprises a first reactor, a second reactor, a condenser, a heat exchanger, a fractionation and rectification device, a gas dryer and a feed pipe, the feeding pipe is used for inputting mixed gas into a feeding hole of the reactor; the reactors are used for catalyst placement and reaction, the condenser is used for condensing liquid products such as methanol dimethyl ether, the liquid products enter the fractionation and rectification device, and gas flows through the gas dryer through a raw material recovery pipe and enters the second reactor for reaction; the heat exchanger applies heat of the first reactor and the second reactor to the fractionation and rectification device; according to the condenser, through the design of the spiral pipeline, the low-temperature environment of the condenser is maintained; the reactor can be matched with different catalysts and drying agents according to the proportion of reaction gas through the annular arrangement design of the tube nests, so that the yield of a target product is improved.

Description

Technical Field

[0001] This utility model relates to the field of chemical production technology, and in particular to a methanol production system with a ring-shaped tubular reactor. Background Technology

[0002] The development of fossil fuels has provided humanity with high-quality fuels, leading to a long-term and extensive dependence on them. As environmental protection and sustainable development concepts gain wider acceptance, people realize that fossil fuel use results in a continuous increase in carbon dioxide emissions, a greenhouse gas that will undoubtedly have a significant negative impact on the Earth's environment and future. With rapid technological advancements, people are increasingly focusing on the development of other clean energy sources. Methanol, often referred to as "liquid sunshine," has gained considerable attention. Methanol serves as both a potential energy carrier and an important chemical raw material. Therefore, methanol production technology has attracted significant interest. Among these, the hydrogenation of carbon monoxide and carbon dioxide to produce methanol is a crucial pathway for the effective utilization of carbon resources and the reduction of greenhouse gas emissions.

[0003] Currently, the main process for producing methanol involves introducing carbon monoxide, carbon dioxide, and hydrogen into a methanol reactor, where methanol and water are produced under high temperature, high pressure, and catalytic conditions. Although the methanol production process is relatively mature and in production, the low equilibrium conversion rate of carbon dioxide and high energy consumption make methanol less competitive in the energy market. Therefore, there is significant room for improvement in the process of producing methanol using carbon monoxide and carbon dioxide.

[0004] Existing methanol reactor designs are monotonous, resulting in incomplete reaction between the reactant gas and catalyst, leading to reduced catalytic efficiency. Ineffective condensation devices in existing units cause incomplete product separation, with generated gaseous methanol and water re-entering the reaction, further decreasing efficiency. Therefore, optimizing the methanol reactor's heat utilization to reduce energy consumption, efficiently separating products to minimize their re-entry, and improving reactor design to enhance reaction efficiency and simplify catalyst replacement are crucial considerations for carbon monoxide / carbon dioxide hydrogenation to methanol production plants. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides the following technical solution:

[0006] A methanol production system with a ring-shaped tubular reactor includes a first reactor, a second reactor, a condenser, a heat exchanger, a fractionation and distillation unit, a gas dryer, and conduits;

[0007] The outlets of the first reactor and the second reactor are connected to the condenser inlet via conduits. The condenser is used to condense the discharged products. The condenser is equipped with a condenser outlet one and a condenser outlet two. The condenser outlet one is connected to the fractionation and distillation apparatus, and the condenser outlet two is connected in sequence to the gas dryer and the inlet of the second reactor. The first reactor and the second reactor are respectively connected to the fractionation and distillation apparatus via heat exchangers.

[0008] Furthermore, the inlet of the first reactor is provided with a feed pipe for introducing a mixed gas of carbon monoxide, carbon dioxide, and hydrogen into the inlet of the first reactor; a first inlet pipe and a second inlet pipe are connected in parallel on the feed pipe, the first inlet pipe is used to introduce carbon monoxide and carbon dioxide gas, and the second inlet pipe is used to introduce hydrogen gas; a compressor is provided on both the first inlet pipe and the second inlet pipe; a gas detector is also connected in parallel on the feed pipe for detecting the ratio of carbon monoxide, carbon dioxide, and hydrogen in the reaction gas.

[0009] Furthermore, the first condenser outlet is connected to the fractionation and distillation device via a liquid outlet pipe; the second condenser outlet is connected to the gas dryer via a raw material recovery pipe; the gas dryer and the second reactor are connected via a conduit, and a compressor is installed in series and a gas dryer is installed in parallel on the conduit connecting the gas dryer and the second reactor.

[0010] Furthermore, the gas dryer is used to dry the raw material gas discharged from the condenser, and the desiccant of the gas dryer includes, but is not limited to, calcium oxide.

[0011] Furthermore, the condenser is externally connected to a coolant circulation motor, and a coolant feed pipe is provided at the inlet of the coolant circulation motor. The condenser is externally wound with a spiral pipe. The coolant is circulated in the spiral pipe by the external coolant circulation motor, so that the coolant is kept at a low temperature, and the temperature of the condenser is lower and more uniformly distributed. This allows a greater temperature difference to be formed between the condenser and the gas flowing in from the inlet, thereby causing more products to condense into liquid.

[0012] Furthermore, the fractionation and distillation apparatus is equipped with a methanol collection pipe. The fractionation and distillation apparatus is used to purify methanol products. The heat exchanger uses the heat from the first reactor and the second reactor to provide heat to the fractionation and distillation apparatus.

[0013] Furthermore, the first reactor and the second reactor have the same structural design. The first reactor includes a material column and an outer shell. The material column is located inside the outer shell, and several catalytic layers and adsorption layers are arranged from the inside to the outside inside the material column.

[0014] Furthermore, the catalytic layer and the adsorption layer are alternately arranged, and both the catalytic layer and the adsorption layer are composed of several columns of tubes arranged at circumferential intervals; several mesh holes are opened on the tube wall, and several mounting holes are opened on the material column corresponding to the positions of the tubes.

[0015] Furthermore, the diameter of the tubes in the catalyst layer is larger than the diameter of the tubes in the adsorption layer.

[0016] Furthermore, a partition is installed at the bottom of the material column in a pull-out manner, and the tubes are placed on the partition through the mounting holes; connecting caps are detachably installed at both ends of the material column.

[0017] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0018] This invention uses a gas detector to detect the proportions of carbon monoxide, carbon dioxide, and hydrogen in the raw material gas, and makes adjustments accordingly to ensure a high conversion rate of carbon monoxide and carbon dioxide in the reaction.

[0019] The heat from the first and second reactors can be reused in the fractionation and distillation unit through a heat exchanger, reducing heat loss and energy consumption.

[0020] By using the spiral pipe design of the condenser, in conjunction with the coolant circulation motor, the coolant circulates in the spiral pipe, resulting in a lower and more uniform temperature distribution in the condenser. This increases the temperature difference between the gas entering the condenser and the condenser itself, leading to more condensation products.

[0021] By setting several catalytic layers and adsorption layers, each composed of several circumferentially spaced tubes, on the material columns of the first and second reactors, catalysts can be placed in the catalytic tubes and adsorbents in the adsorption tubes. The mesh design of the tubes ensures that the catalyst is heated more evenly and the reaction is more complete. The adsorbent can adsorb the water produced in the reaction, which can not only promote the forward reaction but also increase the conversion rate of carbon monoxide and carbon dioxide, improve selectivity, and reduce the water content discharged into the condenser, thereby improving the efficiency of subsequent condensation and distillation. In addition, the independent tube design facilitates the replacement of old and new catalysts and makes the reactor suitable for reactions with various gas ratios. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the system composition of this utility model;

[0023] Figure 2 This is a schematic diagram of the condenser structure of this utility model;

[0024] Figure 3 This is a schematic diagram of the structure of the first reactor of this utility model;

[0025] Figure 4 This is a schematic diagram of the explosion of the first reactor of this utility model;

[0026] Figure 5 This is a schematic diagram of the tube arrangement of this utility model.

[0027] In the diagram: First intake pipe-1, Second intake pipe-2, Compressor-3, Feed pipe-4, Gas detector-5, Coolant feed pipe-6, Coolant circulation motor-7, First reactor-8, Material column-81, Mounting hole-811, Slot-812, Clip-813, Connecting cover-82, Tube column-83, Baffle-84, Condenser-9, Spiral pipe-91, Condensate inlet-911, Condensate outlet-912, Condensate outlet one-92, Condensate outlet two-93, Condensate inlet-94, Gas dryer-10, Second reactor-11, Fractionation and distillation unit-12, Raw material recovery pipe-13, Liquid outlet pipe-14, Methanol collection pipe-15, Heat exchanger-16. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Example 1:

[0030] Please see Figure 1-3 A methanol production system with a ring-shaped tubular reactor includes a first reactor 8, a second reactor 11, a condenser 9, a heat exchanger 16, a fractionation and distillation unit 12, a gas dryer 10, and conduits.

[0031] The outlets of the first reactor 8 and the second reactor 11 are connected to the condensation inlet 94 of the condenser 9 via conduits. The condenser 9 is used to condense the discharged products. The condenser 9 is provided with a first condensation outlet 92 and a second condensation outlet 93. The first condensation outlet 92 is connected to the fractionation and distillation apparatus 12, and the second condensation outlet 93 is connected in sequence to the gas dryer 10 and the inlet of the second reactor 11. The first reactor 8 and the second reactor 11 are respectively connected to the fractionation and distillation apparatus 12 via a heat exchanger 16.

[0032] In this embodiment, the inlet of the first reactor 8 is provided with a feed pipe 4, which is used to input a mixed gas of carbon monoxide, carbon dioxide and hydrogen into the inlet of the first reactor 8; a first inlet pipe 1 and a second inlet pipe 2 are connected in parallel on the feed pipe 4, the first inlet pipe 1 is used to input carbon monoxide and carbon dioxide gas, and the second inlet pipe 2 is used to input hydrogen; a compressor 3 is provided on both the first inlet pipe 1 and the second inlet pipe 2; a gas detector 5 is also connected in parallel on the feed pipe 4 to detect the ratio of carbon monoxide, carbon dioxide and hydrogen in the reaction gas;

[0033] In this embodiment, the condenser outlet 92 of the condenser 9 is connected to the fractionation and distillation apparatus 12 via a liquid outlet pipe 14; the condenser outlet 93 of the condenser 9 is connected to the gas dryer 10 via a raw material recovery pipe 13; the gas dryer 10 and the second reactor 11 are connected by a conduit, and a compressor 3 is installed in series and a gas dryer 10 is installed in parallel on the conduit connecting the gas dryer 10 and the second reactor 11.

[0034] In this embodiment, the gas dryer 10 is used to dry the raw material gas discharged from the condenser 9. The dryer of the gas dryer 10 includes, but is not limited to, calcium oxide. The condenser 9 is externally connected to a coolant circulation motor 7. A coolant feed pipe 6 is provided on the inlet of the coolant circulation motor 7. A spiral pipe 91 is wound around the outside of the condenser 9. The external coolant circulation motor 7 is connected in series with the condensant inlet 911 and condensant outlet 912 of the spiral pipe 91 to form a loop, so that the coolant circulates in the spiral pipe 91, so that the coolant maintains a lower temperature, so that the temperature of the condenser 9 is lower and more uniformly distributed. This allows the condenser 9 to form a larger temperature difference with the gas flowing in from the inlet, thereby causing more products to condense into liquid. The fractionation and distillation device 12 is provided with a methanol collection pipe 15. The fractionation and distillation device 12 is used to purify methanol products. The heat exchanger 16 uses the heat from the first reactor 8 and the second reactor 11 to provide heat to the fractionation and distillation device 12.

[0035] In this embodiment, the first reactor 8 and the second reactor 11 have the same structural design. The first reactor 8 includes a material column 81 and a shell. The material column 81 is located inside the shell, and several catalytic layers and adsorption layers are arranged from the inside to the outside inside the material column 81. The catalytic layers and adsorption layers are arranged alternately, and each catalytic layer and adsorption layer is composed of several circumferentially spaced tubes 83. Several mesh holes are opened on the tube walls of the tubes 83. The material column 81 is a hollow tubular structure. Several mounting holes 811 are opened at the upper end of the material column 81 corresponding to the position of the tubes 83, and the lower end is an open structure. The diameter of the tubes 83 of the catalytic layer is larger than the diameter of the tubes 83 of the adsorption layer. A partition 84 is installed in a pull-out manner below the material column 81, and the tubes 83 pass through... The material column 81 is placed on the partition plate 84 through the mounting hole 811. A slot 812 is provided on the outer wall below the material column 81. The partition plate 84 is slidably inserted into the material column 81 through the slot 812. The partition plate 84 has a filter plate structure, that is, several through slots are opened on the partition plate 84. In order to ensure airtightness, a sealing gasket is provided on the closed contact surface between the partition plate 84 and the slot 812. A snap-fit ​​groove 813 is provided below the material column 81 to facilitate the removal of the partition plate 84. Connecting caps 82 are detachably installed at both ends of the material column 81. The connecting caps 82 are connected to the material column 81 by threads or snap-fit. After the connecting caps 82 at the lower end of the material column 81 are installed, they cover the partition plate 84. This has the advantage of preventing the partition plate 84 from falling out and further ensuring airtightness.

[0036] Example 2:

[0037] Please see Figure 1-3 According to Example 1, this utility model provides a novel carbon monoxide and carbon dioxide hydrogenation reaction system. Carbon monoxide and carbon dioxide enter through the first inlet pipe 1, and hydrogen enters through the second inlet pipe 2. After mixing, they are fed into the first reactor 8 through the feed pipe 4. A gas detector 5 is designed in a branch of the feed pipe 4 to detect the proportion of raw material gas and make adjustments.

[0038] After the raw material gas reacts in the first reactor 8, the generated products and unreacted reaction gas enter the condenser 9 through a conduit.

[0039] The generated product is condensed into a liquid in condenser 9. The liquid flows into fractionation and distillation unit 12 through liquid outlet pipe 14. The unreacted gas passes through raw material recovery pipe 13 and is dried in gas dryer 10 to remove moisture before entering the second reactor 11. A gas detector 5 is installed on this branch to detect the gas composition. When the hydrogen content in the raw material recovery gas is insufficient, another hydrogen feed pipe 4 can be installed in the second reactor 11 to meet the reaction conditions.

[0040] In this embodiment, the first air inlet pipe 1 and the second air inlet pipe 2 are respectively connected in parallel to the feed pipe 4 via corresponding compressors 3. The raw material recovery pipe 13 is connected from the gas outlet of the condenser 9 to the second reactor 11, and a corresponding compressor 3 is also designed in this pipe. Through this structure, the system mixes pressurized carbon monoxide, carbon dioxide and hydrogen and sends it into the second reactor 11 to meet the pressure required by the second reactor 11 and realize the recovery of residual raw materials in the product.

[0041] In this embodiment, a branch-connected gas detector 5 is installed before the reaction gas or raw material recovery gas enters the first reactor 8 and the second reactor 11. With this design, the gas composition can be intuitively understood, and the composition of the catalyst can be adjusted from the product according to the gas composition and target. For the second reactor 11, additional gas can be introduced into the second reactor according to the composition of the raw material recovery gas.

[0042] Example 3

[0043] Please see Figure 1-3 According to embodiments 1-2, this application also proposes a novel condenser design; the condenser 9 is externally wound with a spiral pipe 91 and externally connected to a coolant circulation motor 7, so that the coolant circulates in the spiral pipe 91.

[0044] When the reactor produces gaseous products, the temperature is high, requiring the products to be condensed into liquid in condenser 9. The condensate circulates under the action of the cooling liquid circulation motor 7, promptly removing heat from the gaseous products, lowering the temperature of condenser 9, and making the temperature of condenser 9 more uniform. For methanol products, under normal pressure, methanol changes from a gaseous state to a liquid state at around 60℃. By using an appropriate condenser, the temperature of the condenser can be significantly reduced. This large temperature difference allows more methanol products to condense into liquid and enter the next fractionation and distillation unit 12. Although not shown in the schematic diagram, in actual use, an insulation layer can be added to the outside of condenser 9, which can further reduce and unify the temperature while also reducing energy consumption.

[0045] Example 4:

[0046] Please see Figure 1-3According to embodiments 1-3, this application also proposes a novel reactor design; the first reactor 8 and the second reactor 11 have the same structural design, the first reactor 8 or the second reactor 11 includes a material column 81 and a shell, the material column 81 is located inside the shell, and several catalytic layers and adsorption layers are arranged from the inside to the outside inside the material column 81; the catalytic layers and adsorption layers are arranged alternately, and each catalytic layer and adsorption layer is composed of several circumferentially spaced tubes 83; several mesh holes are opened on the tube wall of the tubes 83, and several mounting holes 811 are opened on the material column 81 corresponding to the positions of the tubes 83 for mounting the tubes 83; the diameter of the tubes 83 in the catalytic layer is larger than the diameter of the tubes 83 in the adsorption layer;

[0047] In this embodiment, the carbon monoxide and carbon dioxide hydrogenation reaction system is designed with two reactors, namely the first reactor 8 and the second reactor 11. The purpose is to change the composition of the catalyst according to the gas composition of different feed gases. When the feed gas reacts in the first reactor 8, the gas composition will change. For example, when the carbon dioxide content introduced into the first reactor 8 is high, the carbon monoxide content in the discharged gas may be relatively high after the reaction. At this time, other types of catalysts can be placed in the second reactor 11 to cope with the change in gas composition. Therefore, the second reactor 11 is designed to place a more suitable catalyst for the gas after the reaction to improve the reactor yield.

[0048] For the reactor design, the reactor is placed in a high-temperature, high-pressure device, employing an independent array of tubes 83 of varying sizes to achieve different functional purposes. For the reactor, an important aspect is maximizing the contact area between the catalyst and the gas to ensure a complete reaction; another crucial factor is the ease of use of the instrument. In this design, the catalytic layer of tubes 83 is vertically arranged, surrounding the reactor to maximize the contact area between the catalyst and the gas. Smaller tubes 83 are arranged in the gaps between the tubes to form an adsorption layer. These tubes 83 are used to hold a desiccant. In the catalytic reaction, water is a major byproduct; appropriate adsorption of excess water can both promote the forward reaction and increase the selectivity of the target product, while reducing the amount of water entering the condenser 9.

[0049] In this embodiment, both ends of the tube 83 are detachably fitted with caps, facilitating the replacement of the catalyst and desiccant inside the tube 83. The caps feature a fine mesh structure to prevent catalyst from falling out and ensure smooth flow of the reactant gas. Both ends of the material column 81 are detachably fitted with connecting caps 82. By opening the connections at both ends and sliding out the partition 84, the tube 83 inside the material column 81 can be removed. Then, by sliding and inserting the partition 84, a new tube 83 can be inserted from above the material column 81. Finally, the connecting caps 82 at both ends are installed to replace the tube 83. In the reactor design, a single catalyst is not necessarily required; the independent tube design facilitates the placement of bifunctional catalysts. Therefore, this design not only facilitates catalyst replacement but also allows for the replacement of one or more catalysts based on the proportion of the feed gas and the requirements of the target product.

[0050] Example 5:

[0051] Please see Figure 1-3 According to Examples 1-4, the carbon monoxide and carbon dioxide hydrogenation reaction system of this application also includes a heat exchanger 16. Since the reaction generates a large amount of heat, the heat exchanger 16 is used to transfer the heat from the first reactor 8 and the second reactor 11 to the fractionation and distillation apparatus 12, thereby reducing the system energy consumption.

[0052] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A methanol production system with a ring-shaped tubular reactor, characterized in that, Includes a first reactor, a second reactor, a condenser, a heat exchanger, a fractionation and distillation unit, a gas dryer, and conduits; The outlets of the first reactor and the second reactor are connected to the condenser inlet; the condenser is provided with condenser outlet one and condenser outlet two, condenser outlet one is connected to the fractionation and distillation device, and condenser outlet two is connected in sequence to the gas dryer and the inlet of the second reactor; the first reactor and the second reactor are respectively connected to the fractionation and distillation device through heat exchangers.

2. The methanol production system with a ring-shaped tubular reactor according to claim 1, characterized in that, The first reactor is equipped with a feed pipe at its inlet, and a first air inlet pipe and a second air inlet pipe are connected in parallel on the feed pipe. Both the first air inlet pipe and the second air inlet pipe are equipped with compressors. A gas detector is also connected in parallel on the feed pipe.

3. The methanol production system with a ring-shaped tubular reactor according to claim 1, characterized in that, The outlets of the first reactor and the second reactor are respectively connected to the condenser via conduits; the condenser is externally designed with a spiral pipe; the first condenser outlet is connected to the fractionation and distillation device via a liquid outlet pipe; the second condenser outlet is connected to the gas dryer via a raw material recovery pipe; the gas dryer and the second reactor are connected via conduits, and a compressor is installed in series and a gas dryer is installed in parallel on the conduits connecting the gas dryer and the second reactor.

4. The methanol production system with a ring-shaped tubular reactor according to claim 1, characterized in that, The condenser is externally connected to a coolant circulation motor, and a coolant inlet pipe is provided at the inlet of the coolant circulation motor.

5. A methanol production system with a ring-shaped tubular reactor according to claim 1, characterized in that, The fractionation and distillation apparatus is equipped with a methanol collection pipe.

6. A methanol production system with a ring-shaped tubular reactor according to claim 1, characterized in that, The first reactor and the second reactor have the same structural design. The first reactor includes a material column and an outer shell. The material column is located inside the outer shell, and several catalytic layers and adsorption layers are arranged from the inside to the outside inside the material column.

7. A methanol production system with a ring-shaped tubular reactor according to claim 6, characterized in that, The catalytic layer and the adsorption layer are alternately arranged, and both the catalytic layer and the adsorption layer are composed of several tubes arranged circumferentially at intervals; several mesh holes are opened on the tube wall, and several mounting holes are opened on the material column corresponding to the position of the tubes.

8. A methanol production system with a ring-shaped tubular reactor according to claim 7, characterized in that, The diameter of the tubes in the catalytic layer is larger than that in the adsorption layer.

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