Tubular reaction chamber, reactor, methanol reforming hydrogen production method and numerical simulation method

Abstract

The invention provides a tubular reaction chamber, a reactor, a methanol reforming hydrogen production method and a numerical simulation method. The tubular reaction cavity comprises a plurality of extension tube sections and a plurality of contraction tube sections, wherein the number of the extension tube sections is not less than that of the contraction tube sections; the extension pipe sections and the contraction pipe sections are arranged at intervals, and the diameter of the extension pipe sections is larger than that of the contraction pipe sections. The reactor comprises an evaporation unit, a combustion chamber and the tubular reaction cavity. According to the tubular reaction cavity and the reactor provided by the invention, through the structure that the extension tube sections and the contraction tube sections are arranged at intervals, the volume of the reaction cavity can be reduced, the surface area of the reaction cavity can be increased, the tortuosity of a reactant mass transfer path can be increased, the retention time of reactants in the reaction cavity can be prolonged, and meanwhile, the radial heat exchange efficiency is improved; the heat transfer efficiency is improved, so that the reaction is fully carried out.

Description

Technical Field

[0001] The present invention relates to the field of hydrogen energy technology, and in particular to a tubular reaction chamber, a reactor, a methanol reforming hydrogen production method and a numerical simulation method. Background Art

[0002] As energy crisis and environmental pollution become increasingly serious, the development of efficient and clean new energy sources has attracted much attention. Hydrogen has a good prospect in meeting current and future energy needs due to its unique advantages of high energy density, zero carbon emissions and renewability, and has been widely used in recent years. However, the immaturity of hydrogen storage technology and transportation difficulties, as well as the high cost of fuel storage and refueling infrastructure, have greatly hindered the development of hydrogen energy. In order to effectively solve the difficulties in hydrogen storage and transportation, in addition to vigorously developing and researching hydrogen storage and transportation technology, another feasible solution is to use alcohols and hydrocarbons for in-situ online hydrogen production.

[0003] Compared with traditional hydrogen production and storage and transportation, online hydrogen production is more convenient and safer. Among many hydrogen-containing carriers, methanol has a low temperature requirement of 250-300 °C for steam reforming. It has outstanding advantages such as wide renewable sources, high hydrogen-to-carbon ratio, convenient storage and transportation, low price and easy availability, and easy process implementation. It is the preferred raw material for in-situ online hydrogen production. Methanol reforming hydrogen production is currently a relatively mature method of hydrogen production. Methanol and water are mixed in a certain proportion. After preheating and vaporization, a reforming reaction is carried out under the action of a catalyst. The main products generated are H2 and CO2, and usually less than 1% of CO.

[0004] The methanol steam reforming reaction is an endothermic reaction and requires additional heat. The internal structure of the reactor will affect the overall heat and mass transfer efficiency and the activity of the catalyst, thereby affecting the hydrogen production performance. The methanol steam reforming hydrogen production reactor mainly includes tubular reactors, microreactors, membrane reactors, etc. The existing technical literature "Numerical Study on Multi-channel Reactors for Methanol Steam Reforming to Produce Synthesis Gas under Different Operating Conditions" ( "Numerical investigation of a multichannel reactor for syngas production by methanol steam reforming at various operating conditions”,International Journal of Hydrogen Energy,Volume 45, Issue 29, 26 May 2020, Pages 14790-14805 ) disclosed a multichannel reactor with a bifurcated inlet manifold, a rectangular outlet manifold and 16 parallel microchannels, and numerically simulated the methanol steam reforming using a triple rate kinetic model. The maximum temperature difference in the reactor was only 2.5 K, which was much lower than other reactors reported in the literature. However, the residence time of the reactants in the reactor was short, the reaction process was incomplete, and the methanol conversion rate was low.

[0005] At present, how to overcome the shortcomings of existing technologies, design a more complete reaction chamber and reactor, and improve the performance of methanol reforming to produce hydrogen is a topic of great application value. Summary of the invention

[0006] The present invention provides a tubular reaction chamber and a reactor, which optimize the internal structure of the reaction chamber, strengthen the heat and mass transfer process, and solve the problems of low heat transfer efficiency and insufficient endothermic reaction in the reaction chamber in the prior art.

[0007] For the methanol steam reforming hydrogen production reaction, the methanol conversion rate and hydrogen production performance can be improved.

[0008] According to one aspect of the present invention, a tubular reaction chamber is provided, which includes a plurality of extended pipe segments and a plurality of contracted pipe segments, wherein the number of the extended pipe segments is not less than the number of the contracted pipe segments; the extended pipe segments and the contracted pipe segments are arranged at intervals, and the diameter of the extended pipe segments is greater than the diameter of the contracted pipe segments.

[0009] According to a tubular reaction chamber provided by the present invention, the total length of the tubular reaction chamber is 20-100 mm; the diameter of the extension tube section is 2-5 mm, and the length is 3-5 mm; the diameter of the contraction tube section is 0.5-1.5 mm, and the length is 0.5-1.5 mm.

[0010] According to a tubular reaction chamber provided by the present invention, the diameter of the contraction tube section is 0.5 mm and the length is 1 mm; or the diameter of the contraction tube section is 1 mm and the length is 0.5 mm.

[0011] According to a tubular reaction chamber provided by the present invention, the number of the extended tube segments is 5-21, and the number of the contracted tube segments is 4-20.

[0012] According to a tubular reaction chamber provided by the present invention, the number of the extended tube segments is equal to the number of the contracted tube segments plus one.

[0013] According to another aspect of the present invention, a reactor is provided, comprising an evaporation unit, a combustion chamber and any one of the tubular reaction chambers as described above, wherein the evaporation unit is connected to the inlet of the tubular reaction chamber, and the combustion chamber is arranged outside the tubular reaction chamber.

[0014] According to a reactor provided by the present invention, a plurality of the above-mentioned tubular reaction chambers are arranged in parallel inside the reactor.

[0015] According to another aspect of the present invention, there is provided a method for producing hydrogen by reforming methanol, using any one of the reactors described above, comprising the following steps: uniformly filling a granular catalyst inside the tubular reaction chamber; conveying a mixture of methanol and water to the evaporation unit, wherein the mixture is evaporated into a gaseous state, i.e., a gaseous mixture of methanol and water, in the evaporation unit; conveying the gaseous mixture from the evaporation unit into the tubular reaction chamber through the inlet of the tubular reaction chamber, wherein the gaseous mixture undergoes a reforming reaction in the tubular reaction chamber to generate hydrogen and carbon dioxide, and the combustion chamber provides the reaction chamber with heat required for the reforming reaction; and discharging the generated hydrogen and carbon dioxide from the outlet of the tubular reaction chamber.

[0016] According to another aspect of the present invention, there is provided a numerical simulation method for hydrogen production by methanol reforming, comprising the following steps: constructing a three-dimensional geometric model of any tubular reaction chamber as described above and catalyst particles therein; based on the three-dimensional geometric model, using the lattice Boltzmann method to numerically simulate the reactant diffusion process in the tubular reaction chamber, and calculating the reactant concentration; when the reactant diffusion process reaches a steady state, calculating the effective diffusion coefficient of the tubular reaction chamber along the reactant entry direction, wherein the effective diffusion coefficient characterizes the flow and diffusion rate of the reactants.

[0017] According to a numerical simulation method for methanol reforming to produce hydrogen provided by the present invention, rebound boundary conditions are set on the surface of the catalyst particles and the inner surface of the tubular reaction chamber; and first-type boundary conditions are respectively set at the inlet and outlet of the tubular reaction chamber.

[0018] The present invention also provides a numerical simulation device for hydrogen production by reforming methanol, comprising: a model construction unit, used to construct a three-dimensional geometric model of the tubular reaction chamber provided by the present invention and the catalyst particles therein; a diffusion simulation unit, used to numerically simulate the reactant diffusion process in the tubular reaction chamber based on the three-dimensional geometric model and adopt the lattice Boltzmann method to calculate the reactant concentration; a coefficient calculation unit, used to calculate the effective diffusion coefficient of the tubular reaction chamber along the reactant entry direction when the reactant diffusion process reaches a steady state, wherein the effective diffusion coefficient characterizes the flow and diffusion rate of the reactant.

[0019] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, a numerical simulation method for producing hydrogen by reforming methanol as described above is implemented.

[0020] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the numerical simulation method for producing hydrogen by reforming methanol as described in any one of the above is implemented.

[0021] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the numerical simulation method for producing hydrogen by reforming methanol as described above is implemented.

[0022] The tubular reaction chamber and reactor provided by the present invention can reduce the volume of the reaction chamber, increase the surface area of ​​the reaction chamber, increase the tortuosity of the reactant mass transfer path, prolong the residence time of the reactants in the reaction chamber, and improve the radial heat exchange efficiency. The improvement of the heat transfer efficiency is conducive to the full progress of the reaction.

[0023] In the case of methanol steam reforming hydrogen production reaction, the residence time of the methanol steam mixed reactants in the reactor is increased, so that the reactants and the catalyst are fully in contact, and the reaction process is carried out more completely. Compared with the reaction chamber and reactor in the prior art, it has the advantages of high methanol conversion rate and high hydrogen production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 The side view schematic diagram of a common tubular reaction chamber (a) in the prior art and the side view schematic diagram of a tubular reaction chamber (b) provided by the present invention are shown; Figure 2 It is a schematic diagram of the heat transfer process of the tubular reaction chamber provided by the present invention; Figure 3 The three-dimensional geometric model of the tubular reaction chamber provided by the present invention and the common tubular reaction chamber is shown, and each reaction chamber is filled with a catalyst; Figure 4 The effect of the diameter of the local contraction structure on the diffusion process of substances in the reaction chamber is shown; Figure 5 The effect of the length of the local contraction structure on the diffusion process of substances in the reaction chamber is shown; Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Tubular reactors are commonly used reactors for methanol steam reforming reactions. The reactor consists of two concentric cylinders arranged in a shell-and-tube type. The methanol steam reforming process is usually carried out in the tube, while the catalytic combustion process is considered to be carried out in the shell. Tubular reactors are generally used in continuous operation processes. Traditional reforming reactors are mostly tube-in-tube type with uniform axial temperature distribution. Tubular reactors have the advantages of simple structure, convenient processing, and convenient replacement of reaction catalysts, but at the same time there are disadvantages of relatively poor heat exchange effect. The radial temperature distribution of the catalyst bed is uneven, resulting in the catalyst performance not being able to perform to the best. When the catalyst load is fixed, increasing the number of tubes and reducing the tube diameter can increase the methanol conversion rate, but it will also increase the CO concentration in the reformed gas.

[0028] Microchannel reactors are catalytic reaction devices with microscale channels, which have great advantages in mass transfer and heat transfer. Compared with conventional reactors, microreactors usually have the advantages of fast mixing of different reactants, high heat exchange efficiency, precise temperature control, low incidence of side reactions, and high safety. However, microreactors and membrane reactors are still in the experimental research stage, and the hydrogen production is low. They need to be integrated in series or parallel to increase the hydrogen production.

[0029] The present invention combines the characteristics of a tubular reactor and a microreactor to provide a tubular reaction chamber with a local contraction structure.

[0030] Combine the following Figure 1 , Figure 2 The tubular reaction chamber provided by the present invention is described in detail.

[0031] Figure 1 (a) shows a common tubular reaction chamber in the prior art. Based on the common tubular reaction chamber, the present invention adopts a design with different diameters in the length direction to provide a new reaction chamber structure, such as Figure 1 (b) shown. Figure 1 The methanol reforming hydrogen production reaction chamber shown in (b) includes a plurality of extended pipe segments and a plurality of contracted pipe segments, the number of the extended pipe segments is not less than the number of the contracted pipe segments; the extended pipe segments and the contracted pipe segments are arranged at intervals, and the diameter of the extended pipe segments is greater than the diameter of the contracted pipe segments.

[0032] For the convenience of further detailed description, the ordinary tubular reaction chamber can be named D0, and the tubular reaction chamber with a local contraction structure provided by the present invention can be named DdLl, wherein d represents the diameter of the contraction tube section, and l represents the length of the contraction tube section, both in mm.

[0033] For example, the total length L of the tubular reaction chamber of the present invention may be 20-100 mm, the diameter D of the extension tube section may be 2-5 mm, the length may be 3-5 mm, the diameter d of the contraction tube section may be 0.5-1.5 mm, and the length may be 0.5-1.5 mm. For example, when the total length L of the reaction chamber is 20 mm and the diameter D of the extension tube section is 2 mm, preferably, the diameter d of the contraction tube section is 0.5 mm, 1 mm or 1.5 mm, and the length l is 0.5 mm, 1 mm or 1.5 mm.

[0034] In one embodiment of the present invention, a contraction pipe segment is arranged between every two extension pipe segments, that is, the number of extension pipe segments is equal to the number of contraction pipe segments plus one. The number of extension pipe segments is at least two, and the number of contraction pipe segments is at least one. Preferably, the number of extension pipe segments is 5-21, and the number of contraction pipe segments is 4-20.

[0035] exist Figure 1 In the schematic diagram of (b), the diameters of the extension pipe sections are equal, and the lengths except the first and last sections are also equal; the diameters of the contraction pipe sections are equal, and the lengths are equal; but the specific implementation of the present invention is not limited thereto, that is, the diameters and lengths of the extension pipe sections and / or the diameters and lengths of the contraction pipe sections can also be set to be different or not completely the same. In actual use, the total length of the reaction chamber, the diameter D of the extension pipe sections, the number of contraction pipe sections, the diameter d, the length l and other parameters can be adjusted according to the actual demand for hydrogen production.

[0036] In one embodiment, the tubular reaction chamber of the present invention is an integrated reaction chamber for methanol steam reforming hydrogen production reaction. The interior of the tubular reaction chamber is evenly filled with a granular catalyst; the outside of the reaction chamber is a combustion chamber of a microreactor, which provides heat for the methanol steam reforming reaction. The reactant is a mixed solution of methanol and water, which is transported to an evaporation unit and evaporated into a gaseous state at high temperature. The gaseous mixture of methanol and water enters the reaction chamber from the inlet at one end of the reaction chamber, and a reforming reaction occurs under high temperature conditions to generate hydrogen, carbon dioxide and a small amount of by-product carbon monoxide, and the reaction products and unreacted reactants are discharged from the outlet at the other end of the reaction chamber.

[0037] The methanol steam reforming reaction includes three reactions: methanol reforming as shown in formula (1), methanol decomposition as shown in formula (2), and water gas shift as shown in formula (3): (1) (2) (3) The methanol reforming hydrogen production reaction chamber of the present invention can reduce the volume of the reaction chamber and increase the surface area of ​​the reaction chamber by arranging an internal local contraction structure, while increasing the tortuosity of the methanol-water vapor mixed reactant in the mass transfer direction, thereby prolonging the residence time of the methanol-water vapor mixed reactant in the reaction chamber and improving the heat transfer efficiency, which is beneficial to the methanol-water vapor reforming hydrogen production reaction and improves the methanol conversion rate.

[0038] Specifically, according to Fourier's law shown in the following formula (4), the increase in the surface area of ​​the reaction chamber promotes the heat transfer between the combustion chamber and the reaction chamber. When the temperature difference between the two ends of the wall is constant, the larger the heat transfer area, the greater the heat transfer amount. Compared with the ordinary tubular reaction chamber, the heat transfer reaction chamber with a variable tube diameter of the present invention can increase the surface area of ​​the reaction chamber. In addition, in addition to being able to transfer heat from the outside to the inside along the radial direction to the center of the reaction chamber (such as Figure 2 middle Q 1), and can also be transferred into the reactor by adding a circular ring portion perpendicular to the inflow direction of the methanol-water vapor mixed reactant after the contraction tube section is added (such as Figure 2 middle Q 2).

[0039] (4) in, Q For heat transfer, k is the thermal conductivity, A is the heat transfer area, Δ T is the temperature difference on both sides of the reaction chamber wall, δ is the wall thickness of the reaction chamber.

[0040] In order to illustrate the advantages of the reaction chamber with an extended tube section and a contracted tube section of the present invention, the reaction chamber of the present invention and the ordinary tubular reaction chamber in the prior art under five different geometric parameters are compared. The calculation results of the surface area, volume and specific surface area of ​​these six reaction chambers are shown in Table 1.

[0041] Table 1 Common tubular reaction chamber and tubular reaction chamber of the present invention with different geometric parameters

[0042] The calculation uses a common tubular reaction chamber D0 with a diameter of 2 mm and a length of 20 mm as a control structure.

[0043] When the length of the contraction tube section is 1 mm, as the diameter of the contraction tube section decreases, the surface area of ​​the reaction chamber first increases and then decreases, but the effect is small; the reduction in the diameter of the contraction tube section gradually reduces the volume. On the whole, the reduction in the diameter of the contraction tube section is beneficial to the methanol steam reforming reaction. When the diameter of the contraction tube section is 1 mm, as the length of the contraction tube section decreases, the surface area and volume of the reaction chamber gradually increase. Among the five different geometric parameters of the reaction chamber of the present invention, the surface area of ​​the D1L0.5 reaction chamber, that is, the heat transfer area, is the largest, and the heat transfer effect is best promoted. The time required for the diffusion process of the substance in the D0.5L1 reaction chamber to reach a steady state is the longest.

[0044] It should be noted that although the above example of the reaction chamber of the present invention is smaller in volume than the D0 reaction chamber in the prior art, the reduction in volume does not mean that the reactants contained are reduced, because during the use of the reactor, the reactants continuously enter from the inlet, rather than filling the reactor with reactants and then closing the inlet for heating. There are always substances flowing in and out of the reaction chamber.

[0045] In order to further verify the feasibility of the reaction chamber structure provided by the present invention, the present invention also carried out numerical simulation verification. Figure 3-Figure 5 Specific description.

[0046] First, a three-dimensional geometric model of a common tubular reaction chamber and a reaction chamber with a contracted tube section of the present invention is constructed. Specifically, numerical reconstruction can be performed using, for example, Microsoft Visual Studio software and C# language programming. For the spherical catalyst in the reaction chamber, an algorithm for generating a porous medium model is used, such as a random growth four-parameter generation method. The reconstruction results are shown in FIG. Figure 3 As shown, the six groups of figures (a)-(f) respectively show a stereoscopic view, a side view and a cross-sectional view of a reaction chamber filled with catalyst particles. Figure (a) is the D0.5L1 reaction chamber of the present invention, Figure (b) is the D1L1 reaction chamber of the present invention, Figure (c) is the D1.5L1 reaction chamber of the present invention, Figure (d) is the D1L0.5 reaction chamber of the present invention, Figure (e) is the D1L1.5 reaction chamber of the present invention, and Figure (f) is the D0 reaction chamber of the prior art; the dark blue part is the outer shell of the reaction chamber, the yellow-green part is the cross-section of the reaction chamber perpendicular to the flow direction of the reactants, the yellow part represents the catalyst particles, and the green part represents the void area inside the reaction chamber except the catalyst.

[0047] Based on the reconstructed geometric model of the reaction chamber filled with spherical catalysts, the lattice Boltzmann method (LBM) is used to numerically simulate the diffusion process in the reaction chamber. The methanol-water vapor mixed reactant diffuses from one side of the reaction chamber to the other side. Ignoring the convection process in material transport, the diffusion process of the reactants can be described by Fick's law in formula (5): (5) in, C reactant is the local concentration of the reactant; D reactant is the local diffusion coefficient of the reactant in the electrolyte.

[0048] The lattice Boltzmann evolution equation including the collision and migration steps is shown in formulas (6) and (7). Formula (6) is the calculation formula for the collision process, and formula (7) is the calculation formula for the migration process: (6) (7) Among them, the subscript α Represents the migration direction of the distribution function; x is the coordinate of a grid point to be calculated; t is time; Δ t is the time step; τ is the relaxation factor; F α for f α They are the pre-collision distribution function and the post-collision distribution function respectively; e α is the grid speed; is the equilibrium distribution function.

[0049] The present invention can select a single relaxation (SRT) or multiple relaxation (MRT) three-dimensional model for calculation, and the discrete lattice velocity can have 7 directions (D3Q7), 15 directions (D3Q15), 19 directions (D3Q19), etc. Preferably, the single relaxation and D3Q19 models are used in this solution, and the discrete lattice velocity is shown in formula (8): (8) The weights of the distribution functions of different speed directions of the D3Q19 model are: ; ; (9) Relaxation Factors in the Lattice Boltzmann Evolution Equation τ Determined by the local diffusion coefficient of the reactant, the relationship follows formula (10): (10) Macroscopic concentration of reactants C The calculation of is shown in formula (11): (11) Rebound boundary conditions were set on the surface of the catalyst particles and the inner wall of the reaction chamber. The initial concentration of the reaction mixture in the voids of the reaction chamber was C 0 = 0 mol m -3 The first type of boundary conditions are set at the inlet and outlet of the reaction chamber.

[0050] When the diffusion process reaches a steady state, the concentration of the reactants at each point in the calculation area no longer changes. The effective diffusion coefficient of the reaction chamber along the reactant inflow direction can be calculated through the simulation results of the diffusion process and formula (12). The smaller the effective diffusion coefficient, the slower the flow and diffusion rate of the reactants in the reactor, the longer the time they stay in the reaction chamber, and the more complete the reforming reaction.

[0051] (12) in, x , y , z Represents three directions in the 3D model space, D eff is the effective diffusion coefficient of the entire reaction chamber, D 0 is the local diffusion coefficient of the substance, C in and C out is the substance concentration at the reactor inlet and outlet.

[0052] Ratio of effective diffusion coefficient between the reaction chamber with contraction tube section of the present invention and the tubular reaction chamber of the prior art D DdLl,eff / D D0,eff It can be used to characterize the magnitude of the hindering effect of setting the contraction tube section on the diffusion process of the substance in the reaction chamber. The calculation results are as follows: Figure 4 and Figure 5 As shown. The calculation results show that compared with the traditional tubular reaction chamber, the reaction chamber with a contraction tube section of the present invention can effectively prolong the residence time of the reactants in the reaction chamber. As the diameter of the contraction tube section decreases and the length increases, the more obvious the hindering effect on the diffusion process of the substance in the reaction chamber, the longer the residence time of the reactants. Among the five geometric parameters used as examples of the reaction chamber of the present invention, D0.5L1 is the solution with the best effect improvement.

[0053] The present invention also provides a methanol reforming hydrogen production reactor, which includes an evaporation unit, a combustion chamber, and a heat transfer reaction chamber with a variable tube diameter as described above. The evaporation unit is connected to the inlet of the reaction chamber, and the reactants evaporated into a gaseous state in the evaporation unit enter the reaction chamber from the inlet. The combustion chamber is arranged outside the tubular reaction chamber to provide heat required for the reaction.

[0054] Preferably, a plurality of heat transfer reaction chambers may be arranged in parallel inside the reactor, so as to further increase the hydrogen production per unit time of the reactor.

[0055] The high heat transfer performance reactor proposed in the present invention has a structure in which the reaction chamber is arranged at intervals between the extended pipe section and the contracted pipe section, thereby improving the radial heat exchange efficiency and increasing the residence time of the reactants in the reaction chamber, so that the reactants are fully in contact with the catalyst, and the reaction process is more complete. Compared with the reactor in the prior art, the hydrogen production performance is significantly improved.

[0056] It should be noted that, although the above-mentioned embodiment is a reaction chamber and a reactor for producing hydrogen by reforming methanol, the present invention is obviously not limited thereto, but can be applied to various reaction chambers and reactors that need to improve the heat and mass transfer efficiency.

[0057] The numerical simulation device for producing hydrogen by reforming methanol provided by the present invention is introduced below. The numerical simulation device for producing hydrogen by reforming methanol and the numerical simulation method for producing hydrogen by reforming methanol described above can correspond to each other.

[0058] The numerical simulation device for hydrogen production by methanol reforming comprises: a model building unit, which is used to build a three-dimensional geometric model of the tubular reaction chamber provided by the present invention and the catalyst particles therein; a diffusion simulation unit, which is used to numerically simulate the reactant diffusion process in the tubular reaction chamber based on the three-dimensional geometric model and adopt the lattice Boltzmann method to calculate the reactant concentration; and a coefficient calculation unit, which is used to calculate the effective diffusion coefficient of the tubular reaction chamber along the reactant entry direction when the reactant diffusion process reaches a steady state, wherein the effective diffusion coefficient characterizes the flow and diffusion rate of the reactant.

[0059] Figure 6 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 6 As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630 and a communication bus 640, wherein the processor 610, the communication interface 620 and the memory 630 communicate with each other through the communication bus 640. The processor 610 may call the logic instructions in the memory 630 to execute a numerical simulation method for hydrogen production by methanol reforming, the method comprising: constructing a three-dimensional geometric model of the tubular reaction chamber and the catalyst particles therein provided by the present invention; based on the three-dimensional geometric model, using the lattice Boltzmann method to numerically simulate the reactant diffusion process in the tubular reaction chamber and calculate the reactant concentration; when the reactant diffusion process reaches a steady state, calculating the effective diffusion coefficient of the tubular reaction chamber along the reactant entry direction, the effective diffusion coefficient characterizing the flow and diffusion rate of the reactant.

[0060] In addition, the logic instructions in the above-mentioned memory 630 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0061] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the numerical simulation method for methanol reforming to produce hydrogen provided by the above methods, and the method includes: constructing a three-dimensional geometric model of the tubular reaction chamber provided by the present invention and the catalyst particles therein; based on the three-dimensional geometric model, using the lattice Boltzmann method to numerically simulate the reactant diffusion process in the tubular reaction chamber and calculate the reactant concentration; when the reactant diffusion process reaches a steady state, calculating the effective diffusion coefficient of the tubular reaction chamber along the reactant entry direction, and the effective diffusion coefficient characterizes the flow and diffusion rate of the reactant.

[0062] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the numerical simulation method for methanol reforming to produce hydrogen provided by the above-mentioned methods, the method comprising: constructing a three-dimensional geometric model of the tubular reaction chamber provided by the present invention and the catalyst particles therein; based on the three-dimensional geometric model, using the lattice Boltzmann method to numerically simulate the reactant diffusion process in the tubular reaction chamber and calculate the reactant concentration; when the reactant diffusion process reaches a steady state, calculating the effective diffusion coefficient of the tubular reaction chamber along the reactant entry direction, the effective diffusion coefficient characterizing the flow and diffusion rate of the reactant.

[0063] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0064] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A tubular reaction chamber, characterized in that: It comprises a plurality of extension pipe segments and a plurality of contraction pipe segments, wherein the number of the extension pipe segments is not less than the number of the contraction pipe segments; the extension pipe segments and the contraction pipe segments are arranged at intervals, and the diameter of the extension pipe segments is greater than the diameter of the contraction pipe segments.

2. The tubular reaction chamber according to claim 1, characterized in that: The total length of the tubular reaction chamber is 20-100 mm; the diameter of the extended tube section is 2-5 mm, and the length is 3-5 mm; the diameter of the contracted tube section is 0.5-1.5 mm, and the length is 0.5-1.5 mm.

3. The tubular reaction chamber according to claim 2, characterized in that: The diameter of the shrinkable tube section is 0.5 mm and the length is 1 mm; or the diameter of the shrinkable tube section is 1 mm and the length is 0.5 mm.

4. The tubular reaction chamber according to any one of claims 1 to 3, characterized in that: The number of the extension pipe segments is 5-21, and the number of the contraction pipe segments is 4-20.

5. The tubular reaction chamber according to claim 4, characterized in that: The number of the extended pipe sections is equal to the number of the contracted pipe sections plus one.

6. A reactor, comprising an evaporation unit, a combustion chamber and a tubular reaction chamber as claimed in any one of claims 1 to 5, wherein the evaporation unit is connected to an inlet of the tubular reaction chamber, and the combustion chamber is arranged outside the tubular reaction chamber.

7. The reactor according to claim 6, characterized in that A plurality of tubular reaction chambers are arranged in parallel inside the reactor.

8. A method for producing hydrogen by reforming methanol, using the reactor as claimed in claim 6 or 7, comprising the following steps: Uniformly filling the interior of the tubular reaction chamber with a granular catalyst; The mixed liquid of methanol and water is transported to the evaporation unit, and the mixed liquid is evaporated into a gaseous state, that is, a gaseous mixture of methanol and water in the evaporation unit; The gaseous mixture is transported from the evaporation unit into the tubular reaction chamber through the inlet of the tubular reaction chamber, the gaseous mixture undergoes a reforming reaction in the tubular reaction chamber to generate hydrogen and carbon dioxide, and the combustion chamber provides the reaction chamber with heat required for the reforming reaction; The generated hydrogen and carbon dioxide are discharged from the outlet of the tubular reaction chamber.

9. A numerical simulation method for hydrogen production by methanol reforming, characterized in that: The steps include: Constructing a three-dimensional geometric model of the tubular reaction chamber and the catalyst particles therein as described in any one of claims 1 to 5; Based on the three-dimensional geometric model, a lattice Boltzmann method is used to numerically simulate the reactant diffusion process in the tubular reaction chamber to calculate the reactant concentration; When the reactant diffusion process reaches a steady state, the effective diffusion coefficient of the tubular reaction chamber along the reactant entry direction is calculated, and the effective diffusion coefficient represents the flow and diffusion rate of the reactant.

10. The numerical simulation method according to claim 9, characterized in that: Rebound boundary conditions are set on the surface of the catalyst particles and the inner surface of the tubular reaction chamber; and first-type boundary conditions are set at the inlet and outlet of the tubular reaction chamber, respectively.

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