Heat exchange type double-cone gap impinging stream micro-reactor for exothermic reaction

Abstract

The present application belongs to the technical field of chemical reaction equipment, and discloses a heat exchange type double-cone gap impinging stream micro-reactor for exothermic reaction, which comprises an outer conical connecting pipe, the top opening of which is connected with a vertical liquid inlet pipe, and the left opening of which is connected with a mixed liquid outlet pipe; an inner conical connecting pipe coaxially arranged inside the outer conical connecting pipe and having a gap L I, the right opening of the inner conical connecting pipe being connected with the front end of a horizontal liquid inlet pipe; the front ends of the outer conical connecting pipe and the inner conical connecting pipe each have a conical portion, and the front end conical portion of the inner conical connecting pipe is provided with a plurality of spaced-apart micropores. The present application combines the double-cone gap impinging stream structure with the inner and outer heat exchange channels, and provides a micro-reactor integrating efficient mixing, heat transfer enhancement and high-throughput design, which can maintain the environmental stability of exothermic reaction under extreme conditions, and improve the reaction safety and product quality stability.

Description

Technical Field

[0001] This invention relates to the field of chemical reaction equipment technology, and in particular to a heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions, which is an enhanced heat and mass transfer device for high-pressure, high-exothermic reactions. Background Technology

[0002] Microreactors, as core equipment for enhancing heat and mass transfer in exothermic reactions, play a crucial role in fields such as chemical engineering, pharmaceuticals, and energy. Traditional microreactors generally suffer from problems such as low mixing efficiency, long processing times, and poor temperature control accuracy. This is especially true in fine chemical synthesis and nanomaterial preparation, which involve high pressure and high exothermic processes. Uneven fluid distribution and heat accumulation can easily lead to safety risks, and low-throughput designs are difficult to meet the needs of large-scale industrial production.

[0003] Existing microreactors often employ simplified flow channel designs, such as single straight channels or T-shaped mixing units, relying on molecular diffusion under laminar flow conditions as the primary mixing mechanism. This lack of active turbulence-promoting methods leads to uneven fluid distribution, slow interfacial diffusion, and mixing uniformity often below 0.5. When processing high-viscosity or easily reactive materials, this can easily trigger side reactions or product quality fluctuations. Furthermore, traditional equipment typically places heat exchangers externally in the mixing zone, using jackets or coils. This results in high thermal resistance, slow response, and an inability to precisely control reaction temperature. In high-exothermic scenarios, heat accumulation can cause local temperature fluctuations exceeding ±10℃, increasing the risk of thermal runaway. In addition, non-concentric shaft layouts and low-density micropore distribution further lead to poor pressure uniformity and increased flow dead zones, limiting throughput to below 400 L / H, making them unsuitable for high-throughput applications. These structural defects not only prolong mixing time and affect reaction efficiency but also restrict the adaptability of microreactors in extreme environments, highlighting the urgent need for innovative solutions.

[0004] Therefore, there is an urgent need for a microreactor that can solve the problems of low mixing efficiency, insufficient heat exchange capacity and limited flux, so as to break through the technical bottleneck of traditional equipment in high-pressure and high-exothermic reaction scenarios. Summary of the Invention

[0005] To address the technical problems existing in the prior art, the purpose of this invention is to provide a heat-exchange type double-cone gap impingement flow microreactor. This invention, through the combination of a double-cone gap impingement flow structure and internal and external heat exchange channels, provides a microreactor integrating efficient mixing, enhanced heat transfer, and high-throughput design.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions includes: an outer conical connecting pipe, the top opening of which is connected to a vertical liquid inlet pipe, and the left opening of which is connected to a mixed liquid outlet pipe;

[0008] The inner conical connecting tube is coaxially arranged inside the outer conical connecting tube and has a gap LⅠ. The opening on the right side of the inner conical connecting tube is connected to the front end of the horizontal liquid inlet tube. The front ends of both the outer conical connecting tube and the inner conical connecting tube have conical parts. The conical part at the front end of the inner conical connecting tube is provided with several micropores distributed at intervals.

[0009] The vertical section of the condensate inlet pipe of the inner heat exchange channel is inserted into and connected to the top opening of the horizontal inlet pipe. The horizontal section is placed inside the horizontal inlet pipe and is connected in sequence to the first inner heat exchange connecting pipe, the second inner heat exchange connecting pipe, and the horizontal section of the condensate outlet pipe of the inner heat exchange channel placed inside the mixed liquid outlet pipe. The vertical section of the condensate outlet pipe of the inner heat exchange channel extends out from the top opening of the mixed liquid outlet pipe and is connected to it. The first and second inner heat exchange connecting pipes are placed in the inner conical connecting pipe and have a gap LⅡ. The outside of the second inner heat exchange connecting pipe is fixed to the front end face of the inner conical connecting pipe, and there is a gap between the second inner heat exchange connecting pipe, the outer conical connecting pipe, and the mixed liquid outlet pipe that allows fluid to flow.

[0010] An external heat exchange tube is sleeved outside the connection between the outer conical connecting pipe and the liquid outlet pipe of the mixed liquid, and has a gap LⅢ. The bottom opening of the external heat exchange tube is connected to the condensate inlet pipe of the external heat exchange channel, and the top opening of the external heat exchange tube is connected to the condensate outlet pipe of the external heat exchange channel.

[0011] Furthermore, the inner diameter of the horizontal inlet pipe is 18mm-25mm, the volumetric flow rate is 100L / H-378L / H, and the flow velocity is 0.109-0.214m / s.

[0012] Furthermore, the vertical inlet pipe has an inner diameter of 18mm-25mm, a volumetric flow rate of 142.86L / H-550L / H, and a flow velocity of 0.156-0.311m / s.

[0013] Furthermore, the inner diameter of the liquid outlet pipe is 20mm-25mm, and the volumetric flow rate is 242.86L / H-928L / H.

[0014] Furthermore, the micropores are circular through holes, and are evenly distributed in two rings along the circumference of the tapered part at the front end of the inner tapered connecting tube, with 90 holes in each ring.

[0015] Furthermore, the inner diameter of the micropore is 0.2mm-0.6mm, the gap LⅠ width between the inner conical connecting tube and the outer conical connecting tube is 1.5mm-2.5mm, and the flow ratio of the first fluid and the second fluid is 7:10.

[0016] Furthermore, the inner diameter of both the condensate inlet pipe and the condensate outlet pipe of the internal heat exchange channel is 8 mm.

[0017] Furthermore, the inner diameter of both the condensate inlet pipe and the condensate outlet pipe of the external heat exchange channel is 8 mm.

[0018] Furthermore, the gap LⅡ width between the first inner heat exchange connecting pipe and the second inner heat exchange connecting pipe and the inner conical connecting pipe is 3mm-5mm.

[0019] Furthermore, the gap LⅢ width between the connection between the external heat exchange tube and the external conical connecting tube and the mixed liquid outlet tube is 3mm-5mm.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. High-efficiency mixing enhancement: The microreactor of this invention uses an inner conical connecting tube and an outer conical connecting tube arranged coaxially. In the impact mixing zone of the conical section at the front end, combined with the micropore design of the conical section at the front end of the inner conical connecting tube, the first fluid is ejected at high speed through the micropores and collides with the second fluid in the impact mixing zone, forming a double-conical gap impact flow structure. The double-conical gap impact structure generates a turbulent effect, increasing the fluid contact area and relative velocity, ensuring stable fluid flow, overcoming the mixing limitations of traditional microreactors, improving mixing efficiency, shortening mixing time, and reducing side reactions.

[0022] 2. Dual heat exchange for precise temperature control: The microreactor of this invention adopts an integrated design of internal and external dual heat exchange channels. The internal and external heat exchange channels work together to remove the heat released during the reaction in a timely and efficient manner, thereby significantly reducing the safety risks that may be caused by heat accumulation, ensuring the safe conduct of the reaction, and maintaining the environmental stability of the exothermic reaction under extreme conditions (-40℃ to 200℃), thus improving the safety of the reaction and the stability of product quality.

[0023] 3. High throughput and pressure balance optimization: This invention ensures smooth fluid flow by using parameters such as the inner diameter and volumetric flow rate of the horizontal inlet pipe, vertical inlet pipe, and mixed liquid outlet pipe. This reduces dead zones, lowers system pressure drop, and increases the reactor throughput to an upper limit of 928 L / H, meeting the needs of industrial production. It also ensures balanced pressure distribution and improves mass transfer efficiency and reaction stability.

[0024] 4. Compact Structure and High Adaptability: The overall structure of this invention is compact, with ingenious connections between components. The integrated design saves installation space and facilitates operation and maintenance. This reactor is suitable for harsh reaction conditions and has broad application prospects in many fields. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the internal structure of a heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to the present invention.

[0027] Figure 2 This is a schematic diagram of the internal fluid flow direction of a heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to the present invention.

[0028] Figure 3 This is a schematic diagram of the flow direction of condensate in the inner and outer heat exchange channels of a heat exchange type double-cone gap impingement flow microreactor for exothermic reactions according to the present invention.

[0029] Figure 4 This is a schematic diagram of the microporous structure on the inner conical connecting tube of the present invention;

[0030] Figure 5 This is a schematic diagram of the structure at the impact mixing zone of the present invention;

[0031] Figure 6 A schematic diagram of the disassembled structure of a heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to the present invention;

[0032] Figure 7 This is a diagram showing the concentration mixing simulation results in the numerical simulation test of Embodiment 1 of the present invention.

[0033] Figure 8 This is a comparison diagram of the mixing uniformity corresponding to different gap LⅠ widths in the embodiments of the present invention;

[0034] In the diagram, 1. Horizontal inlet pipe; 2. Vertical inlet pipe; 3. Mixed liquid outlet pipe; 4. Inner conical connecting pipe; 5. Outer conical connecting pipe; 6. Impact mixing zone; 7. Micropore; 8. Confluence mixing zone; 9. Condensate inlet pipe of inner heat exchange channel; 101. First inner heat exchange connecting pipe; 102. Second inner heat exchange connecting pipe; 11. Condensate outlet pipe of inner heat exchange channel; 12. Condensate outlet pipe of outer heat exchange channel; 13. External heat exchange pipe; 14. Condensate inlet pipe of outer heat exchange channel; 15. Gap LⅠ; 16. Gap LⅡ; 17. Gap LⅢ. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] Example 1

[0037] Reference Figures 1-6 This embodiment provides a heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions, including: an outer conical connecting pipe 5, the top opening of which is connected to a vertical liquid inlet pipe 2, and the left side opening of which is connected to a mixed liquid outlet pipe 3;

[0038] The inner conical connecting tube 4 is coaxially arranged inside the outer conical connecting tube 5 and has a gap LⅠ15. The opening on the right side of the inner conical connecting tube 4 is connected to the front end of the horizontal liquid inlet tube 1. The front ends of both the outer conical connecting tube 5 and the inner conical connecting tube 4 have conical parts. The conical part at the front end of the inner conical connecting tube 4 is provided with a number of spaced microholes 7.

[0039] The gap between the inner conical connecting pipe 4 and the corresponding conical part of the outer conical connecting pipe 5 forms an impact mixing zone 6, and a section of the mixed liquid outlet pipe 3 serves as a confluence mixing zone 8. The length of the confluence mixing zone 8 is 1 / 3 of the length of the mixed liquid outlet pipe 3.

[0040] Reference Figure 2 The first type of fluid in the horizontal inlet pipe 1 ( Figure 2 The fluid (blue arrow in the middle) flows into the inner conical connecting pipe 4 and then out through several micro-holes 7; the cone angle of the conical part of the inner conical connecting pipe 4 and the outer conical connecting pipe 5 is 60°, and the second fluid in the vertical inlet pipe 2 ( Figure 2(Red arrow in the middle) The first type of fluid flowing out of the micropore 7 is impacted in the impact mixing zone 6 to achieve the first mixing. A section of the mixed liquid outlet pipe 3 serves as the confluence mixing zone 8. After the first mixing, the first type of fluid and the second type of fluid are fully dispersed and mixed in the confluence mixing zone 8, and finally flow out through the mixed liquid outlet pipe 3. Figure 2 The green arrows represent the fluid resulting from the mixture of the first and second fluids.

[0041] It also includes: an inner heat exchange channel condensate inlet pipe 9 and an inner heat exchange channel condensate outlet pipe 11, both of which are L-shaped and symmetrically arranged. The vertical section of the inner heat exchange channel condensate inlet pipe 9 is inserted into and connected to the top opening of the horizontal inlet pipe 1. The horizontal section of the inner heat exchange channel condensate inlet pipe 9 is placed inside the horizontal inlet pipe 1 and is connected in sequence to the first inner heat exchange connecting pipe 101, the second inner heat exchange connecting pipe 102, and the horizontal section of the inner heat exchange channel condensate outlet pipe 11. The vertical section of the inner heat exchange channel condensate outlet pipe 11 extends out from the top opening of the mixed liquid outlet pipe 3. And connected to it; the first internal heat exchange connecting pipe 101 and the second internal heat exchange connecting pipe 102 are placed in the inner conical connecting pipe 4 and have a gap LⅡ16. The outside of the second internal heat exchange connecting pipe 102 is fixed to the front end face of the inner conical connecting pipe 4, and there is a gap between the second internal heat exchange connecting pipe 102 and the outer conical connecting pipe 5 and the mixed liquid outlet pipe 3 that allows fluid to flow. The condensate inlet pipe 9, the first internal heat exchange connecting pipe 101, the second internal heat exchange connecting pipe 102 and the condensate flow channel inside the condensate outlet pipe 11 of the internal heat exchange channel together constitute the internal heat exchange channel.

[0042] An external heat exchange tube 13 is sleeved around the connection between the outer conical connecting pipe 5 and the mixed liquid outlet pipe 3, with a gap LⅢ17. The bottom opening of the external heat exchange tube 13 is connected to the condensate inlet pipe 14 of the external heat exchange channel, and the top opening of the external heat exchange tube 13 is connected to the condensate outlet pipe 12 of the external heat exchange channel. The condensate flow channels inside the external heat exchange tube 13, the condensate inlet pipe 14, and the condensate outlet pipe 12 of the external heat exchange channel constitute the external heat exchange channel.

[0043] Reference Figure 3The blue arrows indicate the flow direction of the condensate in the inner and outer heat exchange channels. The condensate in the inner heat exchange channel flows in from the vertical section of the condensate inlet pipe 9, passes through its horizontal section into the first inner heat exchange connecting pipe 101, then flows into the second inner heat exchange connecting pipe 102, and finally flows out through the horizontal and vertical sections of the inner heat exchange channel condensate outlet pipe 11. The condensate in the outer heat exchange channel enters the internal space of the outer heat exchange pipe 13 from the outer heat exchange channel condensate inlet pipe 14, and then flows out from the outer heat exchange channel condensate outlet pipe 12. This dual-channel design allows the condensate to efficiently exchange heat with the fluid inside the horizontal inlet pipe 1, the front end of the inner conical connecting pipe 4, and the mixture in the impact mixing zone 6 and the confluence mixing zone 8, thereby quickly removing the heat released during the reaction and ensuring the reaction proceeds stably within the set temperature range.

[0044] Both the internal heat exchange channel condensate inlet pipe 9 and the external heat exchange channel condensate inlet pipe 14 use heat transfer oil as condensate. The condensate temperature range is generally -40℃ to 200℃, which can maintain the environmental stability of the exothermic reaction under extreme conditions (-40℃ to 200℃).

[0045] The horizontal inlet pipe 1 has an inner diameter of 18 mm, a volumetric flow rate of 100 L / H, and a flow velocity of 0.109 m / s.

[0046] The vertical inlet pipe 2 has an inner diameter of 18 mm, a volumetric flow rate of 142.86 L / H, and a fluid velocity of 0.156 m / s.

[0047] The inner diameter of the liquid outlet pipe 3 is 25 mm, and the volumetric flow rate is 242.86 L / H.

[0048] Reference Figure 4 The micropores 7 are circular through holes. In this embodiment, there are a total of 180 micropores 7, which are evenly distributed in two rings along the circumference of the tapered part at the front end of the inner tapered connecting tube 4, with 90 micropores in each ring.

[0049] The inner diameter of the micropore 7 is 0.6 mm, the width of the gap LⅠ15 between the inner conical connecting pipe 4 and the outer conical connecting pipe 5 is 1.5 mm, and the flow ratio of the first fluid and the second fluid is 7:10.

[0050] The inner diameter of both the condensate inlet pipe 9 and the condensate outlet pipe 11 of the internal heat exchange channel is 8 mm.

[0051] The inner diameter of both the condensate inlet pipe 14 and the condensate outlet pipe 12 of the external heat exchange channel is 8 mm.

[0052] The gap LⅡ16 between the first inner heat exchange connecting pipe 101, the second inner heat exchange connecting pipe 102 and the inner tapered connecting pipe 4 has a width of 3mm.

[0053] The gap LⅢ17 between the connection point of the external heat exchange tube 13 and the external conical connecting tube 5 and the mixed liquid outlet tube 3 is 5mm wide.

[0054] Example 2

[0055] The difference from Example 1 is as follows:

[0056] The horizontal inlet pipe 1 has an inner diameter of 25 mm, a volumetric flow rate of 378 L / H, and a flow velocity of 0.214 m / s.

[0057] The vertical inlet pipe 2 has an inner diameter of 25 mm, a volumetric flow rate of 550 L / H, and a fluid velocity of 0.311 m / s.

[0058] The inner diameter of the liquid outlet pipe 3 is 25 mm, and the volumetric flow rate is 928 L / H.

[0059] The micropores 7 are circular through holes. In this embodiment, there are a total of 180 micropores 7 in two rings, with 90 in each ring.

[0060] The inner diameter of the micropore 7 is 0.2 mm, the width of the gap LⅠ15 between the inner conical connecting pipe 4 and the outer conical connecting pipe 5 is 2.5 mm, and the flow ratio of the first fluid and the second fluid is 7:10.

[0061] The inner diameter of both the condensate inlet pipe 9 and the condensate outlet pipe 11 of the internal heat exchange channel is 8 mm.

[0062] The inner diameter of both the condensate inlet pipe 14 and the condensate outlet pipe 12 of the external heat exchange channel is 8 mm.

[0063] The gap LⅡ16 between the first inner heat exchange connecting pipe 101, the second inner heat exchange connecting pipe 102 and the inner tapered connecting pipe 4 has a width of 5mm.

[0064] The gap LⅢ17 between the connection point of the external heat exchange tube 13 and the external conical connecting tube 5 and the mixed liquid outlet tube 3 is 3mm wide.

[0065] Reference Figure 5In this invention, the inner diameter of the micropore 7 is 0.2mm-0.6mm, and the width of the gap LⅠ15 between the inner conical connecting pipe 4 and the outer conical connecting pipe 5 is 1.5mm-2.5mm, meaning the width of the impact mixing zone 6 is 1.5mm-2.5mm. Due to the difference in cross-sectional area between the micropore 7 and the impact mixing zone 6, there is a velocity difference between the two continuous phase fluids and the dispersed phase fluid. The flow ratio of the first fluid to the second fluid is 7:10. Efficient mixing of the two fluids is achieved through this flow difference, i.e., the velocity difference. Even if the volumetric flow rates of the two phase fluids are the same, the velocity ratio can still reach approximately 6:1, forming a significant velocity difference. Under turbulent conditions, the impacting flow induces chaotic convection and turbulent kinetic energy dissipation, effectively reducing diffusion time and improving mixing efficiency. This design achieves a rapid and controllable mixing process through structure-induced turbulent dissipation.

[0066] In this invention, the horizontal inlet pipe 1, the inner conical connecting pipe 4, and the outer right side outer wall of the outer conical connecting pipe 5 are connected together by welding. This not only ensures that each annular component is coaxial, but also provides support for the outer walls of the inner conical connecting pipe 4 and the outer conical connecting pipe 5.

[0067] The horizontal inlet pipe 1, the inner conical connecting pipe 4, the outer conical connecting pipe 5, the mixed liquid outlet pipe 3, the horizontal section of the condensate inlet pipe 9 in the inner heat exchange channel, the first inner heat exchange connecting pipe 101, the second inner heat exchange connecting pipe 102, the horizontal section of the condensate outlet pipe 11 in the inner heat exchange channel, and the external heat exchange pipe 13 are coaxially connected to achieve uniform fluid distribution and pressure balance in the reactor.

[0068] In this invention, except for the external heat exchange tube 13 which is made of stainless steel, the base materials of the other components are all Hastelloy alloy.

[0069] The microreactor of the present invention can synthesize organic compounds in liquid-liquid systems with a volumetric flow rate of 100L / H-929L / H. Because the conical gap diversion channel (impact mixing zone 6) and several micropores 7 are uniformly distributed in two rings, and the diameter of the liquid outlet pipe 3 is 20mm-25mm, it can be used for material mixing reactions in pilot and intermediate stages.

[0070] This invention has significant application value in exothermic reaction fields such as fine chemical synthesis and nanoparticle preparation. Its core advantage lies in the synergistic effect of high-precision temperature control and homogenized material distribution: the internal and external dual heat exchange channel design enables precise control of the reaction environment temperature and maintains environmental stability under extreme conditions (-40℃ to 200℃).

[0071] The mixing effect of the heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions in Example 1 of this invention was tested by numerical simulation. The numerical simulation test process is as follows:

[0072] (1) Geometric modeling and mesh generation

[0073] Geometric Construction: A three-dimensional model of the reactor in Example 1 was built in COMSOL. The inner diameters of the horizontal inlet pipe 1 and the vertical inlet pipe 2 are both 18 mm. The width of the gap LⅡ16 between the first inner heat exchange connecting pipe 101, the second inner heat exchange connecting pipe 102 and the inner conical connecting pipe 4 is 3 mm. The width of the gap LⅠ15 between the inner conical connecting pipe 4 and the outer conical connecting pipe 5 is 1.5 mm. The inner diameter of the micropore 7 is 0.6 mm, and the radial length of the micropore 7 is 3 mm (i.e., the wall thickness of the inner conical connecting pipe 4 is 3 mm). The inner diameter of the mixed liquid outlet pipe 3 is 25 mm. The inner diameters of the condensate inlet pipe 9, the condensate outlet pipe 11, the condensate inlet pipe 14 and the condensate outlet pipe 12 of the inner heat exchange channel are all 8 mm. The width of the gap LⅢ17 between the connection of the outer heat exchange pipe 13 and the outer conical connecting pipe 5 and the mixed liquid outlet pipe 3 is 5 mm.

[0074] Mesh generation: The overall model is discretized using a free tetrahedral mesh. Local mesh refinement and boundary layer meshing are applied to areas with strong turbulent disturbances, such as micropore 7, to accurately capture turbulent features such as jets and eddies, while ensuring computational convergence.

[0075] (2) Selection and setting of physical field interface

[0076] Choosing a dual-physics coupling of turbulent flow and rarefied mass transport:

[0077] Turbulent physics: Select a suitable turbulence model (k-ε) for microscale jets to describe the fluid turbulence velocity field, pressure field, turbulent kinetic energy, and dissipation rate distribution, and assume that the fluid is an incompressible Newtonian fluid.

[0078] The physical field for mass transfer of rare matter is the velocity field coupled with turbulent flow, which describes the evolution of the concentration field of solute under turbulent mixing, and considers the enhancing effect of turbulent diffusion on mass transfer.

[0079] (3) Definition of boundary conditions and initial conditions

[0080] Inlet boundary: Horizontal inlet pipe 1 is set with a turbulent inlet velocity of 0.109 m / s and a concentration of 0 mol / m³. 3 The turbulence intensity and turbulence scale were specified; the vertical inlet pipe 2 was set with a flow velocity of 0.156 m / s and a concentration of 1 mol / m³. 3 Simultaneously set turbulence parameters.

[0081] Outlet boundary: Mixed liquid outlet pipe 3 is set as a pressure outlet with a gauge pressure of 0 Pa to ensure continuous fluid flow. At the same time, turbulence variable outlet boundary conditions are set.

[0082] Wall Boundaries: All flow channel walls are set as no-slip walls with wall functions (to adapt to turbulence models), and flux-free boundaries are set to avoid fluid leakage and solute diffusion.

[0083] Initial conditions: The fluid concentration in the flow channel is 0 at the initial moment, and the velocity field and turbulence variables are set to 0 or small disturbances. Start steady-state calculation.

[0084] (4) Solver configuration and steady-state calculation

[0085] Research type: Select steady-state study to obtain the steady-state concentration field distribution of turbulent mixing after full development.

[0086] Solver settings: Use an iterative solver (such as FGMRES) combined with multigrid preprocessing, and set a relative tolerance (such as 10). -6 This enables strongly coupled computation of turbulence-dilute mass transfer, ensuring steady-state convergence.

[0087] Calculation execution: COMSOL iteratively solves the coupled equations of turbulent flow and mass transport until the residuals meet the convergence criteria, obtaining the steady-state flow field and concentration field, such as... Figure 7 As shown.

[0088] (5) Calculate the mixing uniformity MI (Mixing Index)

[0089] The definition of mixing uniformity (MI) is:

[0090] (1);

[0091] In formula (1):

[0092] σ: Standard deviation of fluid concentration obtained from simulation calculation;

[0093] σ max Standard deviation of theoretical maximum concentration;

[0094] When MI→1, σ is much smaller than σ max This indicates that the fluid is uniformly dispersed, close to the ideal mixing target, and the mixing is thorough;

[0095] When MI→0, σ is approximately equal to σ max This indicates that the fluid stratification or clusters have not diffused, resulting in poor mixing.

[0096] The formula for calculating σ is:

[0097] (2);

[0098] In formula (2):

[0099] c i The concentration of fluid monitored at a certain monitoring point;

[0100] The average concentration of the fluid flowing out of the outlet via the mixed liquid outlet pipe 3 after mixing in the mixing zone 8;

[0101] N: Total number of monitoring points;

[0102] The larger the σ, the greater the concentration difference at different locations (the less uniform the mixing, and the more obvious the concentration stratification / clustering).

[0103] The smaller σ is, the closer the concentration is to the mean (the more uniform the mixing and the higher the consistency of the fluid distribution).

[0104] from Figure 7 It can be seen that the first type of fluid flowing out through the micropore 7 and the second type of fluid flowing into the gap LⅠ15 through the vertical inlet pipe 2 collide at the gap LⅠ15. The mixing method is dissipation under turbulent conditions, and the subsequent mixing method relies on molecular diffusion.

[0105] In addition, the mixing uniformity was verified by changing the width of the gap LⅠ15 in this embodiment, and the results were as follows. Figure 8 The diagram shows a comparison of mixing uniformity for different gap widths (LI15). It can be seen from the diagram that when the gap width (LI15) is 1.5mm and 2.5mm, the mixing uniformity can reach 0.98, which is close to 1. The fluid is evenly dispersed within the gap width (LI15) range of 1.5mm-2.5mm, which is close to the ideal mixing target and the mixing is sufficient.

[0106] This invention optimizes the fluid distribution path through a double-cone gap impingement flow structure, ensuring uniform mixing of multiphase materials and providing a fundamental guarantee for efficient reactions. Combined with internal and external dual heat exchange channels, it avoids the shortcomings of traditional equipment in terms of thermal runaway risk and uneven mixing from the source. At the same time, it supports high-throughput production mode to meet the needs of large-scale industrial organic synthesis, improving production efficiency while ensuring product quality consistency, and providing key technical support for the large-scale upgrading of fine chemicals.

[0107] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions, characterized in that, include: The outer conical connecting pipe has its top opening connected to the vertical liquid inlet pipe and its left opening connected to the mixed liquid outlet pipe. The inner conical connecting tube is coaxially arranged inside the outer conical connecting tube and has a gap LⅠ. The opening on the right side of the inner conical connecting tube is connected to the front end of the horizontal liquid inlet tube. The front ends of both the outer conical connecting tube and the inner conical connecting tube have conical parts. The conical part at the front end of the inner conical connecting tube is provided with several micropores distributed at intervals. The vertical section of the condensate inlet pipe of the inner heat exchange channel is inserted into the top opening of the horizontal inlet pipe and fixed. The horizontal section is placed inside the horizontal inlet pipe and is connected in sequence to the first inner heat exchange connecting pipe, the second inner heat exchange connecting pipe, and the horizontal section of the condensate outlet pipe of the inner heat exchange channel placed inside the mixed liquid outlet pipe. The vertical section of the condensate outlet pipe of the inner heat exchange channel extends out from the top opening of the mixed liquid outlet pipe and is connected to it. The first inner heat exchange connecting pipe and the second inner heat exchange connecting pipe are placed in the inner conical connecting pipe and have a gap LⅡ. The outside of the second inner heat exchange connecting pipe is fixed to the front end face of the inner conical connecting pipe, and there is a gap between the second inner heat exchange connecting pipe, the outer conical connecting pipe, and the mixed liquid outlet pipe to allow fluid flow. An external heat exchange tube is sleeved outside the connection between the outer conical connecting pipe and the liquid outlet pipe of the mixed liquid, and has a gap LⅢ. The bottom opening of the external heat exchange tube is connected to the condensate inlet pipe of the external heat exchange channel, and the top opening of the external heat exchange tube is connected to the condensate outlet pipe of the external heat exchange channel.

2. The heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The horizontal inlet pipe has an inner diameter of 18mm-25mm, a volumetric flow rate of 100L / H-378L / H, and a flow velocity of 0.109m / s-0.214m / s.

3. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The vertical inlet pipe has an inner diameter of 18mm-25mm, a volumetric flow rate of 142.86L / H-550L / H, and a flow velocity of 0.156m / s-0.311m / s.

4. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The inner diameter of the liquid outlet pipe is 20mm-25mm, and the volumetric flow rate is 242.86L / H-928L / H.

5. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The micropores are circular through holes, and are evenly distributed in two rings along the circumference of the tapered part at the front end of the inner tapered connecting tube, with 90 holes in each ring.

6. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The inner diameter of the micropore is 0.2mm-0.6mm, the gap LⅠ between the inner conical connecting tube and the outer conical connecting tube is 1.5mm-2.5mm, and the flow ratio of the first fluid and the second fluid is 7:

10.

7. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The inner diameter of both the condensate inlet pipe and the condensate outlet pipe of the internal heat exchange channel is 8 mm.

8. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The inner diameter of both the condensate outlet pipe of the external heat exchange channel and the condensate outlet pipe of the external heat exchange channel is 8mm.

9. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The gap LⅡ width between the first and second internal heat exchange connecting pipes and the inner conical connecting pipe is 3mm-5mm.

10. A heat-exchange type double-cone gap impingement flow microreactor for exothermic reactions according to claim 1, characterized in that, The gap LⅢ width between the connection between the external heat exchange tube and the external conical connecting tube and the mixed liquid outlet tube is 3mm-5mm.

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