Loop microchannel reactor system

Abstract

The invention provides a loop micro-channel reactor system, and relates to the technical field of chemical engineering, the loop micro-channel reactor system is characterized in that a first-stage reaction mechanism is fixedly communicated with a first-stage circulating pump and a first-stage external heat exchange mechanism through a first-stage circulating pipeline assembly, and the right top of the first-stage reaction mechanism is fixedly communicated with a first-stage reaction outlet pipe; the right end of the first-stage reaction outlet pipe is fixedly communicated with the top input end of the second-stage reaction mechanism, and the second-stage reaction mechanism is fixedly communicated with a second-stage circulating pump and a second-stage external heat exchange mechanism through a second-stage circulating pipeline assembly; the first-stage reaction mechanism, the second-stage reaction mechanism, the first-stage external heat exchange mechanism and the second-stage external heat exchange mechanism are electrically connected with the controller respectively; and the cycle index and the flow velocity of the to-be-reacted material in the cavity of the single reaction unit are adjusted by controlling the rotating speed of the first-stage circulating pump in the circulating pipeline assembly. The multi-stage reaction mechanisms are connected in series, so that the reaction rate and the yield of a target product can be remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical engineering, and in particular to a loop microchannel reactor system. Background Art

[0002] In the field of chemical reactions, the performance of the reactor plays a key role in the reaction effect and production efficiency. Traditional stirred reactors are widely used in many chemical production scenarios due to their flexible and convenient characteristics. It has a relatively simple structure, is easy to operate, and can easily adapt to the needs of reactions of different scales and types. However, this type of reactor has significant limitations. Its pressure resistance is largely limited by the mechanical stirring device. When faced with a high-pressure reaction environment, problems such as the strength and sealing of the mechanical stirring components will make it difficult for the entire reactor to withstand high pressure, thereby limiting its application in the field of high-pressure reactions. At the same time, the mixing effect of traditional stirred reactors is also unsatisfactory. During the stirring process, stirring dead corners are prone to occur, resulting in uneven mixing of materials, affecting the sufficiency and consistency of the reaction, and reducing product quality and production efficiency. In addition, it is difficult for traditional stirred reactors to achieve continuous fluid reaction and automated control.

[0003] With the development of chemical technology, microchannel, fixed bed, and Venturi reactors have emerged. This type of reactor is equipped with a structure that promotes static mixing, and the equipment itself does not require mechanical stirring. This unique structure significantly improves its pressure resistance and can meet the needs of some reactions with higher pressure requirements. Microchannel reactors are designed with different flow channel characteristics to achieve ideal mixing or mass transfer and heat transfer effects, but their mixing or mass transfer effects are ultimately limited by the material flow rate in the reactor. When the material flow rate is low, the mixing effect is poor, affecting the reaction efficiency. When the material flow rate is too high, for the same reactor, the medium residence time becomes correspondingly shorter, which may cause the reaction to fail to proceed fully and make it difficult to achieve the desired reaction effect. For example, patent CN200980143803.X designs a special mixing channel configuration, setting up a tiny channel configuration with a size of 1-5 mm on a reaction plate. For a certain reaction medium flow rate, in order to achieve better mixing or mass transfer and longer residence time, it is necessary to use a smaller reaction channel or increase the number of reaction plates. Patent (CN 222196895 U) achieves material diversion and mixing through a stacked reaction channel design, but still relies on the material flow rate to adjust the mixing effect. Summary of the Invention

[0004] The present invention provides a loop microchannel reactor system to solve at least one of the technical problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides a loop microchannel reactor system, comprising: a primary reaction mechanism, a secondary reaction mechanism, a primary external heat exchange mechanism, a secondary external heat exchange mechanism, a primary circulation pipeline assembly, a secondary circulation pipeline assembly, a first-stage circulation pump, a second-stage circulation pump and a controller, characterized in that: the primary reaction mechanism is fixedly connected to the first-stage circulation pump and the primary external heat exchange mechanism through the primary circulation pipeline assembly, the right top of the primary reaction mechanism is fixedly connected to the first-stage reaction outlet pipe, the right end of the first-stage reaction outlet pipe is fixedly connected to the top input end of the secondary reaction mechanism, the secondary reaction mechanism is fixedly connected to the second-stage circulation pump and the secondary external heat exchange mechanism through the secondary circulation pipeline assembly, and the primary reaction mechanism, the secondary reaction mechanism, the first external heat exchange mechanism and the second external heat exchange mechanism are respectively electrically connected to the controller.

[0006] Preferably, the first-level reaction mechanism includes: a reaction unit cavity one, wherein several layers of mixed fluid microchannel structures for promoting material mixing are fixedly provided inside the reaction unit cavity one, and the several layers of mixed fluid microchannel structures are composed of one or more flow channels. A first cyclone mixer is fixedly installed inside the reaction unit cavity one below the several layers of mixed fluid microchannel structures. A vertical connecting pipe two is fixedly connected to the center of the bottom of the reaction unit cavity one. A first-level liquid buffer is fixedly installed at the connection point of the connecting pipe two inside the reaction unit cavity one. A pair of liquid inlets are fixedly provided symmetrically on the left and right sides of the top of the reaction unit cavity one. A vertical connecting pipe one is fixedly connected to the center of the top of the reaction unit cavity one. A heat medium inlet one is provided at the lower left part of the reaction unit cavity one, and a heat medium outlet one is provided at the upper right part of the reaction unit cavity one.

[0007] Preferably, the primary circulation pipeline assembly includes: a tee, the input end of the connecting pipeline is fixedly connected to the output end of the tee, the top output port of the tee is fixedly connected to the first-stage reaction outlet pipe, a control valve is fixedly installed on the first-stage reaction outlet pipe, the right-end branch port of the tee is fixedly connected to the output port of the first-stage circulation pump, the input port of the first-stage circulation pump is fixedly connected to the output end of the heat exchange pipeline, the input end of the heat exchange pipeline is fixedly connected to the outlet end of the first-stage external heat exchange mechanism, the motor speed range of the first-stage circulation pump and the second-stage circulation pump is 500-5000RPM, and the distance d between the impeller edge of the first-stage circulation pump and the inner wall of the flow channel is at most 10mm.

[0008] Preferably, the first-level external heat exchange mechanism on the left side includes: an external heat exchanger, the output end of the second heat exchange pipe is fixedly connected to the bottom of the external heat exchanger, the bottom inlet end of the external heat exchanger is fixedly connected to the connecting pipe one through the second heat exchange pipe, a heat exchanger heat medium inlet one is fixedly opened at the bottom of the right side wall of the external heat exchanger, and a heat exchanger heat medium outlet one is fixedly opened at the top of the left side wall of the external heat exchanger.

[0009] Preferably, the secondary external heat exchange mechanism on the right has the same structure as the primary external heat exchange mechanism on the left, and a heat exchanger heat medium inlet 2 is fixedly opened at the bottom of the right side wall of the secondary external heat exchange mechanism, and a heat exchanger heat medium outlet 2 is fixedly opened at the top of the left side wall of the secondary external heat exchange mechanism.

[0010] Preferably, the secondary reaction mechanism has the same internal structure as the primary reaction mechanism, and the secondary reaction mechanism includes: a second-stage reaction inlet pipe, the output end of the first-stage reaction outlet pipe is fixedly connected to the second-stage reaction inlet pipe, the right end of the second-stage reaction inlet pipe is fixedly connected to the reaction unit cavity 2, the top center of the reaction unit cavity 2 is fixedly connected to the second-stage reaction outlet pipe, and a heat medium inlet 2 is opened at the lower left part of the reaction unit cavity 2.

[0011] Preferably, a second heat medium outlet is opened at the upper right part of the second reaction unit cavity, several layers of mixed fluid microchannel structures are fixedly provided inside the second reaction unit cavity, a second cyclone mixer is fixedly installed at the bottom end of the second reaction unit cavity, a second-stage liquid buffer is fixedly installed below the second cyclone mixer inside the second reaction unit cavity, and a back pressure valve and a second control valve are fixedly installed on the second-stage reaction outlet pipe from left to right.

[0012] Preferably, the several layers of mixed fluid microchannel structure include: multi-layer mixing flow channels, mesh flow channels, porous microchannels and fixed bed flow channels, and the hydraulic pore size of the internal structure of the multi-layer mixing flow channels, mesh flow channels, porous microchannels and fixed bed flow channels is 10um to 10000um, and the optimal range of the hydraulic pore size is 50um to 5000um.

[0013] Preferably, a plurality of parallel and spaced flow channel baffles 1 are fixedly provided on the multi-layer mixing flow channel, and a fluid channel 1 is formed between two adjacent parallel and spaced flow channel baffles 1;

[0014] The mesh flow channel is composed of a plurality of longitudinal baffles 2 and transverse baffles 3 to form a rectangular flow channel 2, and the connection point between the longitudinal baffles 2 and the transverse baffles 3 is a confluence point;

[0015] A plurality of irregular flow channel dividers are fixedly arranged in the porous microchannel, and the plurality of irregular flow channel dividers divide a plurality of three-dimensional porous flow channels.

[0016] Preferably, two or more groups of primary reaction mechanisms and secondary reaction mechanisms can be connected in series through pipelines to achieve a cascade continuous reaction. The reaction mechanism of each stage is respectively provided with a material inlet and a material outlet, and the material inlet and the material outlet provide online raw material replenishment and material sampling functions for each stage of the reaction mechanism.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention provides a loop microchannel reactor system, which forms a closed-loop reaction loop by synergistically controlling the primary reaction mechanism, the secondary reaction mechanism and the external heat exchange mechanism through a controller. The material enters from the top of the primary reaction mechanism through the circulation pipe assembly. After the preliminary reaction is completed in the reaction unit cavity, the reaction liquid is diverted through a three-way pipe: one path is discharged through control valve one, and the other path is driven by the first-stage circulation pump to enter the external heat exchanger for precise temperature control. The material after heat exchange returns to the bottom of the reaction unit cavity through connecting pipe two to form a cycle. This design enables the reaction system to have multi-parameter coupling control capabilities of temperature-flow-pressure. The multi-stage reaction mechanisms are connected in series to achieve further deepening of the reaction. Through the multi-stage circulation reaction process, the reaction rate and the yield of the target product can be significantly improved;

[0018] Beneficial effects: The loop structure realizes the recycling of reaction liquid and the utilization rate of raw materials is increased by more than 40%; the external heat exchange mechanism is independently set, and the heat exchange efficiency is increased by 2.3 times compared with the traditional jacket type; the controller integrates PID algorithm, and the temperature fluctuation is controlled within the range of ±0.5℃; the modular design facilitates capacity expansion, and the processing capacity of a single system can be adjusted in the range of 1:100 (such as 0.1-10L / H). The circulation pipeline component controls the number of cycles of the reacted materials in the reaction unit cavity in a single reaction unit cavity by controlling the speed of the first-stage circulation pump, avoiding the traditional method being affected by the flow rate of the reacted materials input from the feed port, and avoiding the disadvantages of the traditional method of blindly connecting too many reaction mechanisms in series to increase the reaction contact time and the length of the reaction cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to 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 any creative work.

[0020] Figure 1 This is a diagram of the composition of the loop microchannel reactor system of the present invention;

[0021] Figure 2 This is a structural diagram of a single-stage loop microchannel reactor system of the present invention;

[0022] Figure 31 is a schematic structural diagram of a first cyclone mixer of the present invention;

[0023] Figure 4 It is a schematic diagram of a multi-layer mixing flow channel;

[0024] Figure 5 It is a schematic diagram of the mesh flow channel;

[0025] Figure 6 is a schematic diagram of a porous microchannel;

[0026] Figure 7 This is a schematic diagram of the first-stage circulation pump.

[0027] Reference numerals:

[0028] 1. First-stage reaction mechanism; 2. Second-stage reaction mechanism; 3. First-stage external heat exchange mechanism; 4. First-stage circulation pipeline assembly; 5. Controller; 6. Reaction unit cavity 1; 7. Connecting pipeline 1; 8. Connecting pipeline 2; 9. Heat medium inlet 1; 10. Heat medium outlet 1; 11. Mixed fluid channel structure; 12. First cyclone mixer; 13. First-stage liquid buffer; 14. Liquid inlet 1; 15. Tee; 16. First-stage reaction outlet pipe; 17. Control valve 1; 18. Second-stage reaction inlet pipe; 19. Reaction unit cavity 2; 20. Second-stage reaction outlet pipe; 21. Heat medium inlet 2; 22. Heat medium outlet 2; 23. Second cyclone mixer; 24. Second-stage liquid buffer; 25 , back pressure valve; 26, control valve two; 27, multi-layer mixing flow channel; 28, mesh flow channel; 29, porous microchannel; 30, fixed bed flow channel; 31, flow channel baffle one; 3101, fluid channel one; 32, longitudinal baffle two; 33, transverse baffle three; 3301, rectangular flow channel two; 34, flow channel divider; 3401, three-dimensional porous flow channel; 35, first-stage circulation pump; 36, heat exchange pipe two; 37, external heat exchanger; 38, heat exchange pipe one; 39, heat exchanger heat medium inlet one; 40, heat exchanger heat medium outlet one; 41, secondary external heat exchange mechanism; 42, heat exchanger heat medium inlet two; 43, heat exchanger heat medium outlet two; 44, secondary circulation pipe assembly; 45, second-stage circulation pump. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0030] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0031] In addition, in the present invention, descriptions such as "first" and "second" are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present invention. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions and technical features between the various embodiments can be combined with each other, but this must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0032] The present invention provides the following embodiments

[0033] Example 1

[0034] The embodiment of the present invention provides a loop microchannel reactor system, such as Figure 1 As shown, a loop microchannel reactor system includes: a primary reaction mechanism 1, a secondary reaction mechanism 2, a primary external heat exchange mechanism 3, a secondary external heat exchange mechanism 41, a primary circulation pipeline assembly 4, a secondary circulation pipeline assembly 44, a first-stage circulation pump 35, a second-stage circulation pump 45 and a controller 5, characterized in that: the primary reaction mechanism 1 is fixedly connected to the first-stage circulation pump 35 and the primary external heat exchange mechanism 3 through the primary circulation pipeline assembly 4, the right top of the primary reaction mechanism 1 is fixedly connected to the first-stage reaction outlet pipe 16, the right end of the first-stage reaction outlet pipe 16 is fixedly connected to the top input end of the secondary reaction mechanism 2, the secondary reaction mechanism 2 is fixedly connected to the second-stage circulation pump 45 and the secondary external heat exchange mechanism 41 through the secondary circulation pipeline assembly 44, and the primary reaction mechanism 1, the secondary reaction mechanism 2, the primary external heat exchange mechanism 3 and the secondary external heat exchange mechanism 41 are respectively electrically connected to the controller 5.

[0035] The working principle and beneficial effects of the above technical solution are:

[0036] Working principle: This embodiment uses the controller 5 to coordinately control the primary reaction mechanism 1, the secondary reaction mechanism 2 and the external heat exchange mechanism 3 to form a closed-loop reaction circuit. The material enters from the top of the primary reaction mechanism 1 through the primary circulation pipeline assembly 4. After completing the preliminary reaction in the reaction unit cavity, the reaction liquid is diverted through the three-way pipe 15: one path is discharged through the control valve 17, and the other path is driven by the first-stage circulation pump 35 to enter the external heat exchanger 37 for precise temperature control. The first-stage circulation pump 35 rotates at high speed through the impeller to provide material circulation power and stir and mix the material at high speed; after the material reacts inside the primary reaction mechanism 1, it flows out from the bottom, and the material after heat exchange through the first-stage external heat exchange mechanism 3 returns to the top of the reaction unit cavity through the connecting pipe 7 to form a cycle. The reaction of the secondary reaction mechanism 2 is similar to that of the primary reaction mechanism 1. This design enables the reaction system to have the multi-parameter coupling control capability of temperature-flow-pressure. The multi-stage reaction mechanism is connected in series to form a cascade continuous flow loop microchannel reactor system with the outlet of the previous stage connected to the inlet of the next stage loop reaction unit cavity. This further deepens the reaction and significantly improves the reaction rate and the yield of the target product through the multi-stage cyclic reaction process.

[0037] Beneficial effects: The loop structure realizes the recycling of reaction liquid and the utilization rate of raw materials is increased by more than 40%; the external heat exchange mechanism 3 is independently set, and the heat exchange efficiency is increased by 2.3 times compared with the traditional jacket type; the controller 5 integrates the PID algorithm, and the temperature fluctuation is controlled within the range of ±0.5°C; the modular design facilitates the expansion of production capacity, and the processing capacity of a single system can be adjusted in the range of 1:100 (such as 0.1-10L / H). The first-level circulation pipeline component 4 controls the number of cycles of the reacted material in the reaction unit cavity in a single reaction unit cavity by controlling the speed of the first-stage circulation pump 35, avoiding the traditional method being affected by the flow rate of the reacted material input from the feed port, and avoiding the disadvantage of the traditional method of blindly connecting too many reaction mechanisms in series to increase the reaction contact time and the length of the reaction cavity.

[0038] Example 2

[0039] On the basis of Example 1, Figure 1-Figure 3As shown, the first-level reaction mechanism 1 includes: a reaction unit cavity 6, wherein several layers of mixed fluid microchannel structures 11 for promoting material mixing are fixedly provided inside the reaction unit cavity 6, and the several layers of mixed fluid microchannel structures 11 are composed of one or more flow channels. A first cyclone mixer 12 is fixedly installed inside the reaction unit cavity 6 below the several layers of mixed fluid microchannel structures 11. A vertical connecting pipe 28 is fixedly connected to the center of the bottom of the reaction unit cavity 6. A first-level liquid buffer 13 is fixedly installed at the connection point of the connecting pipe 28 inside the reaction unit cavity 6. A pair of liquid inlets 14 are fixedly provided on the top of the reaction unit cavity 6 symmetrically on the left and right. A vertical connecting pipe 7 is fixedly connected to the center of the top of the reaction unit cavity 6. A heat medium inlet 9 is provided at the lower left part of the reaction unit cavity 6, and a heat medium outlet 10 is provided at the upper right part of the reaction unit cavity 6.

[0040] The primary circulation pipeline assembly 4 includes: a tee pipe 15, the input end of the connecting pipe 7 is fixedly connected to the output end of the tee pipe 15, the top output port of the tee pipe 15 is fixedly connected to the first-stage reaction outlet pipe 16, and a control valve 17 is fixedly installed on the first-stage reaction outlet pipe 16. The right end branch port of the tee pipe 15 is fixedly connected to the output port of the first-stage circulation pump 35, the input port of the first-stage circulation pump 35 is fixedly connected to the output end of the heat exchange pipe 38, and the input end of the heat exchange pipe 38 is fixedly connected to the outlet end of the primary external heat exchange mechanism 3. The motor speed range of the first-stage circulation pump 35 and the second-stage circulation pump 45 is 500-5000RPM, and the distance d between the impeller edge of the first-stage circulation pump 35 and the second-stage circulation pump 45 and the inner wall of the flow channel is at most 10mm.

[0041] The first-level external heat exchange mechanism 3 on the left side includes: an external heat exchanger 37, the output end of the heat exchange pipe 2 36 is fixedly connected to the bottom of the external heat exchanger 37, the bottom inlet end of the external heat exchanger 37 is fixedly connected to the connecting pipe 1 8 through the heat exchange pipe 2 36, and a heat exchanger heat medium inlet 1 39 is fixedly opened at the bottom of the right side wall of the external heat exchanger 37, and a heat exchanger heat medium outlet 1 40 is fixedly opened at the top of the left side wall of the external heat exchanger 37.

[0042] The working principle and beneficial effects of the above technical solution are:

[0043] Working Principle: The first-stage reaction mechanism 1 utilizes a dual-vortex mixing structure. After entering through liquid inlet 14, the material first passes through the first vortex mixer 12, generating a spiral flow field. This creates forced convection heat exchange with the heat exchange medium from heat medium inlet 9. The multi-layered structure of the mixed fluid channel structure 11 creates a turbulence enhancement zone, which, in conjunction with the first-stage liquid buffer 13, eliminates pulsating flow. The first-stage circulation pump 35 is driven by a variable-frequency motor. Its impeller-channel clearance (d) is designed to be ≤10mm, achieving a pumping flow accuracy of ±2%. In conjunction with the external heat exchanger 37, it achieves a reaction heat removal efficiency of ≥95%. The external heat exchanger 37 is independent of the reaction unit cavity 6 and is in fluid communication with the circulating mixing system through pipelines such as the heat exchange pipe 1 38 and the heat exchange pipe 2 36. It is used to perform heat exchange on the circulating material. The reacted material enters the top of the reaction unit cavity 6 from the liquid inlet 14. Driven by the first-stage circulation pump 35, the material flows counterclockwise through several layers of mixed fluid microchannel structure 11, the first cyclone mixer 12, the first-stage liquid buffer 13, the heat exchange pipe 2 36, and enters the bottom of the external heat exchanger 37 for heat exchange. The heat-exchanged material flows through the heat exchange pipe 1 38, the first-stage circulation pump 35, the tee 15, and the connecting pipe 7 and finally returns to the top of the reaction unit cavity 6 for the next circulation reaction. The heat medium of the external heat exchanger 37 enters from the heat medium inlet 39 and flows out from the heat medium outlet 40 to complete the heat exchange.

[0044] The feed rate at the loop microchannel reactor system's raw material feed port (liquid inlet 14) is much lower than the internal circulation rate. By optimizing the flow rate control of the first-stage circulation pump 35, the reactant flow rate within the primary reaction mechanism 1 can reach tens or even thousands of times the feed rate. This high flow rate creates a localized turbulent mixing mechanism within the designed flow channel of the primary reaction mechanism 1, eliminating the complex flow channel shapes and layouts of traditional microreactors to achieve mixing and mass transfer, thereby achieving good mixing and mass transfer between the reactants.

[0045] The loop microchannel reactor system circulation mixing system makes the linear velocity of the material in the reaction unit cavity 6 greater than 0.5m / s, preferably 1-5m / s; the number of cycles in the reaction unit cavity 1 is 1-10 times / minute;

[0046] Beneficial effects:

[0047] Improved mixing uniformity: The cyclone mixer makes the mixing uniformity CV value ≤3%, and the reaction selectivity is increased by 15%. The reaction mechanism can select one or more combined flow channels of enhanced mixing structures such as multi-layer mixing channels 27, mesh flow channels 28, porous microchannels 29, and fixed beds. Under the condition of a pressure drop of 0.1 MPa, its flow capacity is 0.5-1000 L / min, preferably 1-500 L / min. The reaction mechanism has a simpler hydraulic structure and has a larger flow capacity and application range than traditional microreactors.

[0048] Anti-clogging design: The gap between the impeller and the flow channel is ≤10mm, which increases pumping efficiency by 40% and enhances anti-clogging capability by three times. Both the first-stage circulation pump 35 and the second-stage circulation pump 45 use an impeller structure to drive material circulation and dynamically mix the materials. The high-speed rotation of the impeller breaks the material droplets into micron-level droplets within 0.1-1 seconds.

[0049] Wide temperature range control: The dual-channel design of the heat medium supports operation in a wide temperature range of -100°C to 400°C, adapting to various reaction requirements. The external heat exchanger 37 is connected to the circulation pipeline of the loop microchannel reactor system, and its heat exchange area can reach 1-5 times the heat exchange area of the first-stage reaction mechanism 1 itself;

[0050] Pressure stability: The buffer reduces pressure fluctuations by more than 80%, extending the service life of the equipment.

[0051] Example 3

[0052] On the basis of Example 2, Figure 2 、 Figure 3 As shown, the secondary external heat exchange mechanism 41 on the right has the same structure as the primary external heat exchange mechanism 3 on the left. A second heat exchanger heat medium inlet 42 is fixedly opened at the bottom of the right wall of the secondary external heat exchange mechanism 41, and a second heat exchanger heat medium outlet 43 is fixedly opened at the top of the left wall of the secondary external heat exchange mechanism 41.

[0053] The secondary reaction mechanism 2 has the same internal structure as the primary reaction mechanism 1. The secondary reaction mechanism 2 includes: a second-stage reaction inlet pipe 18, the output end of the first-stage reaction outlet pipe 16 is fixedly connected to the second-stage reaction inlet pipe 18, the right end of the second-stage reaction inlet pipe 18 is fixedly connected to the reaction unit cavity 2 19, the top center of the reaction unit cavity 2 19 is fixedly connected to the second-stage reaction outlet pipe 20, and a heat medium inlet 21 is opened at the lower left part of the reaction unit cavity 2 19.

[0054] A heat medium outlet 22 is provided at the upper right portion of the reaction unit cavity 19. Several layers of mixed fluid microchannel structures 11 are fixedly provided inside the reaction unit cavity 19. A second cyclone mixer 23 is fixedly installed at the bottom end of the reaction unit cavity 19. A second-stage liquid buffer 24 is fixedly installed below the second cyclone mixer 23 inside the reaction unit cavity 19. A back pressure valve 25 and a control valve 26 are fixedly installed on the second-stage reaction outlet pipe 20 from left to right.

[0055] The working principle and beneficial effects of the above technical solution are:

[0056] Working principle: The secondary reaction mechanism 2 adopts a flow field design that is symmetrical with the primary one. The second-stage reaction inlet pipe 18 receives the pre-reaction liquid from the primary one, and undergoes secondary mixing enhancement through the second cyclone mixer 23 in the reaction unit cavity 19. The back pressure valve 25 and the control valve 2 26 constitute a pressure regulating system. The reaction pressure is maintained within the range of 0.5-5MPa through the back pressure valve 25, and the pressure pulsation is attenuated in conjunction with the second-stage liquid buffer 24. The heat medium inlet 21 and the heat medium outlet 2 22 form an independent temperature control loop, forming a stepped temperature field with the primary system. When the primary reaction mechanism 1 is continuously fed through the liquid inlet 14 or more liquid inlets 14, the chemical reaction in the secondary reaction mechanism 2 further proceeds at the same residence time due to the lack of new raw materials, and the product percentage content in the secondary reaction mechanism 2 will be higher than that of the previous reactor system. The heat medium of the secondary external heat exchange mechanism 41 enters from the heat medium inlet 2 42 and finally flows out through the heat medium outlet 2 43 to complete the heat exchange.

[0057] The second-stage reaction outlet pipe 20 is connected to the back pressure valve 25, and then to the control valve 26. The operating pressure in the reactor system is set by the back pressure valve 25, and the discharge flow rate of the reactor system is controlled by the control valve 26, so that the feeding and discharging are carried out continuously to realize continuous flow reaction.

[0058] Specific process: Since the secondary reaction mechanism 2 has the same internal structure as the primary reaction mechanism 1, the material output from the first-stage reaction outlet pipe 16 of the primary reaction mechanism 1 enters the second-stage reaction inlet pipe 18 of the secondary reaction mechanism 2 and then enters the second reaction unit chamber 19. Within the second reaction unit chamber 19, the material first reacts in the mixed fluid channel structure 11, then passes through the second cyclone mixer 23 for further mixing. It then flows through the second-stage liquid buffer 24, through the secondary circulation pipe assembly 44, through the secondary external heat exchange mechanism 41, and through the second-stage circulation pump 45, returning to the second reaction unit chamber 19 for the next cycle of reaction. During the reaction, heat medium enters through the second heat medium inlet 21, exchanges heat with the material within the second reaction unit chamber 19, and then flows out through the second heat medium outlet 22. After multiple cycles of reaction are completed, the material flows out of the second-stage reaction outlet pipe 20. The backpressure valve 25 maintains a stable pressure within the reaction system, and the second control valve 26 controls the material output flow rate. The second-stage circulation pump 45 provides circulation pressure for the multiple cycles of reaction.

[0059] Beneficial effects: The secondary reaction mechanism 2 has the same structure as the primary reaction mechanism 1 and is connected in series, which further deepens the reaction. Through the two reaction processes, the reaction rate and the yield of the target product can be significantly improved; the re-mixing effect of the second cyclone mixer 23 ensures that the materials entering the secondary reaction mechanism 2 are evenly mixed, providing good conditions for subsequent reactions; the setting of the back pressure valve 25 ensures that the reaction is carried out under a stable pressure environment, which is conducive to the smooth progress of some pressure-sensitive reactions, and improves the selectivity of the reaction and the quality of the product; the control valve 26 can flexibly control the output of the material, which is convenient for adjusting the operating parameters of the reaction system according to production needs.

[0060] Example 4

[0061] On the basis of Example 2, Figure 2-Figure 4 As shown, the multi-layer mixed fluid microchannel structure 11 is composed of one or more flow channels, and the multi-layer mixed fluid microchannel structure 11 includes: multi-layer mixed flow channels 27, mesh flow channels 28, porous microchannels 29 and fixed bed flow channels 30. The hydraulic pore size of the internal structure of the multi-layer mixed flow channels 27, mesh flow channels 28, porous microchannels 29 and fixed bed flow channels 30 is 10um to 10000um, and the optimal range of the hydraulic pore size is 50um to 5000um.

[0062] The multi-layer mixing channel 27 is fixed with a plurality of parallel and spaced flow channel baffles 31, and a fluid channel 3101 is formed between two adjacent parallel and spaced flow channel baffles 31;

[0063] The mesh flow channel 28 is formed by a plurality of longitudinal baffles 2 32 and transverse baffles 33 to form a rectangular flow channel 2 3301, and the connection point between the longitudinal baffles 2 32 and the transverse baffles 3 33 is a confluence point;

[0064] A plurality of irregular flow channel dividers 34 are fixedly provided in the porous microchannel 29 , and the plurality of irregular flow channel dividers 34 divide a plurality of three-dimensional porous flow channels 3401 .

[0065] Two or more groups of first-stage reaction mechanisms 1 and second-stage reaction mechanisms 2 can be connected in series through pipelines to realize a cascade continuous reaction. A material inlet and a material outlet are respectively provided on the reaction mechanism of each stage. The material inlet and the material outlet in the first-stage reaction mechanism 1 are respectively a liquid inlet 14 and a first-stage reaction outlet pipe 16, and the material inlet and the material outlet in the second-stage reaction mechanism 2 are respectively a second-stage reaction inlet pipe 18 and a second-stage reaction outlet pipe 20; the material inlet and the material outlet provide online raw material replenishment and material sampling functions for each stage of the reaction mechanism.

[0066] The working principle and beneficial effects of the above technical solution are:

[0067] Working Principle: In the mixed fluid channel structure 11, the multi-layer mixing channel 27 divides the fluid channel 1 3101 by the channel baffle 1 31, allowing materials to flow and mix in different channels. The meshed channel 28 utilizes the rectangular channel 2 3301 formed by the longitudinal baffle 2 32 and the transverse baffle 3 33, as well as the confluence point, to achieve multiple diversion and confluence of materials, enhancing the mixing effect. The porous microchannel 29 is divided into three-dimensional porous channels 3401 by irregular channel dividers 34, increasing the contact area and flow path of the materials, thereby promoting the reaction. Different channel combinations can be selected and adjusted according to the characteristics and needs of the reaction. When two or more sets of primary reaction mechanisms 1 and secondary reaction mechanisms 2 are connected in series through pipelines, the material inlet of each reaction mechanism can be replenished with raw materials, and the material outlet can be sampled for real-time monitoring of the reaction progress. The materials pass through each reaction mechanism in sequence, reacting in the different channel structures, and gradually completing the entire reaction process.

[0068] Beneficial effects: Various flow channel combinations provide diverse options for different types of reactions, and can optimize reaction conditions according to the characteristics of the reaction (such as reaction rate, reactant characteristics, etc.), thereby improving the applicability and efficiency of the reaction; the unique structure of the multi-layer mixing flow channel 27, the mesh flow channel 28 and the porous microchannel 29 effectively increases the mixing degree and contact area of the materials, promotes the full progress of the reaction, and improves the reaction conversion rate and product quality; the series design of the reaction mechanism and the setting of the material inlet and outlet realize cascade continuous reaction, which not only improves production efficiency, but also facilitates real-time monitoring and adjustment of the reaction process, and can timely replenish raw materials and adjust reaction parameters according to the reaction progress to ensure the smooth progress of the reaction and the stability of product quality.

[0069] Example 5

[0070] On the basis of Example 2, a reaction mechanism abnormal state early warning assessment module is further provided, and the reaction mechanism abnormal state early warning assessment module includes:

[0071] Temperature detection unit 1, used for real-time detection of the temperature of the medium fluid entering the connecting pipe 1 7;

[0072] The second temperature detection unit is used to detect the temperature of the medium fluid flowing out of the second connecting pipe 8 in real time;

[0073] Temperature detection unit 3, used for real-time detection of the temperature value of the first-stage circulation pump 35;

[0074] Temperature detection unit 4, used to detect the temperature of the medium fluid in the external heat exchanger 37;

[0075] Pressure sensor 1, used to detect the pressure value of the medium fluid at the outlet of connecting pipe 2 8;

[0076] Pressure sensor 2, used to detect the pressure value of the medium fluid at the inlet of connecting pipe 1 7;

[0077] Density sensor, used to detect the density value of the medium fluid in the reaction unit cavity 6;

[0078] A flow rate sensor, used to detect the flow rate of the medium fluid in the connecting pipe 17;

[0079] Alarm, used to give an alarm in case of abnormal situation;

[0080] A first calculation unit is used to calculate the friction resistance coefficient of the microchannel reactor;

[0081] a second calculation unit, for calculating an abnormal state evaluation value of the reaction mechanism within a detection time period based on the result of the first calculation unit;

[0082] A comparison and judgment unit, used for comparing and judging the state of the abnormal state evaluation value;

[0083] The control unit is used to collect and process the data from each sensor. The control unit is electrically connected to the first calculation unit, the second calculation unit, the temperature detection unit 1, the temperature detection unit 2, the temperature detection unit 3, the temperature detection unit 4, the flow rate sensor for detecting the flow rate of the medium fluid in the connecting pipe 1 7, the density sensor, the flow sensor, the pressure sensor 1, the pressure sensor 2 and the alarm.

[0084] The first calculation unit is calculated based on the following formula:

[0085] Where: f is the friction coefficient of the microchannel reactor, ρ is the density of the medium fluid in the reaction unit cavity 6 detected by the density sensor, P in is the pressure value of the medium fluid at the inlet of the connecting pipe 7 detected by the pressure sensor, P out is the pressure value of the medium fluid at the outlet of the connecting pipe 2 8 detected by the pressure sensor 2, Re is the Reynolds number of the medium fluid in the reaction unit cavity 1 6, and D h is the average hydraulic diameter of the microchannel, L is the length of the reaction unit cavity, μ f is the dynamic viscosity coefficient of the medium fluid;

[0086] The second calculation unit is based on the first calculation unit and is calculated based on the following formula:

[0087]

[0088] Where: t is the abnormal state evaluation value of the reaction mechanism in the detection time period t, L1 is the total length of the connecting pipe 2 8 and the connecting pipe 1 7, D1 is the inner diameter of the connecting pipe 2 8, vt is the flow rate value of the medium fluid in the connecting pipe 1 7 detected by the flow rate sensor within the detection time period t, T1 is the temperature value of the external heat exchanger 37 detected by the temperature detection unit 4, T out is the temperature value of the medium fluid flowing out of the connecting pipe 2 8 detected by the temperature detection unit 2, T in is the temperature value of the medium fluid entering the connecting pipe 7 detected by the temperature detection unit 1, T max The maximum operating temperature of the first-stage circulating pump 35 detected by the temperature detection unit 3, T min is the minimum operating temperature of the first-stage circulating pump 35 detected by the temperature detection unit 3, ln is a logarithmic function, e is a natural constant with a value of 2.72; A0 is the cross-sectional area of the reaction unit cavity 6, A c is the cross-sectional area of the mixed fluid channel, T w It is the average temperature value of the external heat exchanger 37 detected by the temperature detection unit 29.

[0089] The comparison judgment unit performs comparison, when χ t When the value is greater than the safety threshold, the control unit controls the alarm to sound an alarm, stops the first-stage circulating pump 35 in time, notifies the maintenance personnel to check and repair the reaction mechanism, and cleans or replaces the microchannel components in time. t When the value is less than or equal to the safety threshold, the abnormal state assessment value is normal and no alarm is required.

[0090] The working principle and beneficial effects of the above technical solution are:

[0091] Working Principle: This embodiment integrates multi-parameter monitoring and intelligent assessment modules to achieve real-time diagnosis and risk warning of the operating status of the reaction mechanism. The specific process is as follows:

[0092] Data acquisition layer: Temperature detection units 1 to 4 respectively monitor the temperatures of the inlet of connecting pipe 1 7, the outlet of connecting pipe 2 8, the impeller pump, and the external heat exchanger 37, forming a full-link temperature field monitoring system. Pressure sensors 1 and 12 detect the pressure difference between the inlet and outlet of the connecting pipe, and combine the data from the density sensor and flow rate sensor to reflect the fluid dynamics characteristics.

[0093] Core computing layer: The first computing unit calculates the microchannel friction resistance coefficient f through parameters such as pressure difference, density, and flow velocity to quantify the fluid flow resistance;

[0094] The second calculation unit combines the Reynolds number Re, the hydraulic diameter Dh and the heat exchanger temperature parameters to generate the abnormal state evaluation value χ t , which integrates multi-dimensional information of flow field stability, heat transfer efficiency and equipment operating conditions;

[0095] Decision execution layer: The comparison judgment unit will tDynamically compare with the preset safety threshold. If it exceeds the limit, the alarm will be triggered and the control unit will be linked to execute shutdown protection and maintenance instructions.

[0096] Beneficial effects:

[0097] Fault precursor identification: Sudden changes in the friction resistance coefficient f can provide early warning of microchannel blockage or scaling, avoiding unplanned downtime; impeller pump temperature monitoring can capture bearing overheating or seal leakage in real time to prevent equipment damage accidents.

[0098] Quantitative evaluation of heat exchange performance: abnormal state evaluation value χ t Comprehensively reflects the degree of heat exchanger efficiency attenuation. When χ t When it is greater than the safety threshold, it indicates that the heat exchanger dirt deposition exceeds 20%, and the online cleaning program needs to be started.

[0099] Process safety closed-loop control: Automatically shut down and lock the impeller pump after an alarm to prevent leakage of high-temperature media; maintenance personnel can retrieve historical data (such as f change curve, χ t Overtime period), accurately locate the fault point and improve maintenance efficiency.

[0100] Energy efficiency optimization guidance: Long-term operation data can be analyzed to determine the optimal operating parameters, guide process parameter optimization, and reduce energy consumption.

[0101] Equipment life management: The friction resistance coefficient f is positively correlated with the equipment operating time. The f-time curve can be used to predict the life of microchannel components and achieve preventive maintenance.

[0102] This embodiment upgrades traditional passive maintenance to active early warning. By building a "monitoring-calculation-decision-making" closed-loop system, the operational reliability of the reaction mechanism is improved and maintenance costs are greatly reduced. It is particularly suitable for high-risk and continuous production scenarios.

[0103] 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 various embodiments of the present invention.

Claims

1. A loop microchannel reactor system, comprising a primary reaction mechanism (1), a secondary reaction mechanism (2), a primary external heat exchange mechanism (3), a secondary external heat exchange mechanism (41), a primary circulation pipeline assembly (4), a secondary circulation pipeline assembly (44), a first-stage circulation pump (35), a second-stage circulation pump (45) and a controller (5), characterized in that: The primary reaction mechanism (1) is fixedly connected to the first-stage circulation pump (35) and the primary external heat exchange mechanism (3) through the primary circulation pipeline assembly (4); the right top of the primary reaction mechanism (1) is fixedly connected to the first-stage reaction outlet pipe (16); the right end of the first-stage reaction outlet pipe (16) is fixedly connected to the top input end of the secondary reaction mechanism (2); the secondary reaction mechanism (2) is fixedly connected to the second-stage circulation pump (45) and the secondary external heat exchange mechanism (41) through the secondary circulation pipeline assembly (44); the primary reaction mechanism (1), the secondary reaction mechanism (2), the primary external heat exchange mechanism (3) and the secondary external heat exchange mechanism (41) are respectively electrically connected to the controller (5).

2. A loop microchannel reactor system according to claim 1, characterized in that: The first-stage reaction mechanism (1) comprises: a reaction unit cavity (6), wherein the reaction unit cavity (6) is fixedly provided with a plurality of layers of mixed fluid microchannel structures (11) for promoting material mixing, wherein the plurality of layers of mixed fluid microchannel structures (11) are composed of one or more flow channels, wherein a first cyclone mixer (12) is fixedly installed below the plurality of layers of mixed fluid microchannel structures (11) in the reaction unit cavity (6), wherein the center of the bottom of the reaction unit cavity (6) is fixedly connected to a vertical connecting pipe (8), wherein the first-stage liquid buffer (13) is fixedly installed at the connection point of the connecting pipe (8) in the reaction unit cavity (6), wherein a pair of liquid inlets (14) are fixedly provided on the top of the reaction unit cavity (6) in a symmetrical manner, wherein the center of the top of the reaction unit cavity (6) is fixedly connected to a vertical connecting pipe (7), wherein a heat medium inlet (9) is provided at the lower left portion of the reaction unit cavity (6), and wherein a heat medium outlet (10) is provided at the upper right portion of the reaction unit cavity (6).

3. A loop microchannel reactor system according to claim 2, characterized in that: The primary circulation pipeline assembly (4) comprises: a tee (15), the input end of the connecting pipeline (7) is fixedly connected to the output end of the tee (15), the top output port of the tee (15) is fixedly connected to the first-stage reaction outlet pipe (16), the first-stage reaction outlet pipe (16) is fixedly installed with a control valve (17), the right end branch port of the tee (15) is fixedly connected to the output port of the first-stage circulation pump (35), the input port of the first-stage circulation pump (35) is fixedly connected to the output end of the heat exchange pipeline (38), the input end of the heat exchange pipeline (38) is fixedly connected to the outlet end of the primary external heat exchange mechanism (3), the motor speed range of the first-stage circulation pump (35) and the second-stage circulation pump (45) is 500-5000RPM, and the distance d between the impeller edge of the first-stage circulation pump (35) and the inner wall of the flow channel of the second-stage circulation pump (45) is at most 10mm.

4. A loop microchannel reactor system according to claim 3, characterized in that: The first-level external heat exchange mechanism (3) on the left side includes: an external heat exchanger (37), the output end of the second heat exchange pipe (36) is fixedly connected to the bottom of the external heat exchanger (37), the bottom inlet end of the external heat exchanger (37) is fixedly connected to the connecting pipe (8) through the second heat exchange pipe (36), a heat exchanger heat medium inlet (39) is fixedly opened at the bottom of the right side wall of the external heat exchanger (37), and a heat exchanger heat medium outlet (40) is fixedly opened at the top of the left side wall of the external heat exchanger (37).

5. A loop microchannel reactor system according to claim 1, characterized in that: The secondary external heat exchange mechanism (41) on the right side has the same structure as the primary external heat exchange mechanism (3) on the left side. A heat exchanger heat medium inlet (42) is fixedly provided at the bottom of the right side wall of the secondary external heat exchange mechanism (41), and a heat exchanger heat medium outlet (43) is fixedly provided at the top of the left side wall of the secondary external heat exchange mechanism (41).

6. A loop microchannel reactor system according to claim 3, characterized in that: The secondary reaction mechanism (2) has the same internal structure as the primary reaction mechanism (1), and the secondary reaction mechanism (2) comprises: a second-stage reaction inlet pipe (18); the output end of the first-stage reaction outlet pipe (16) is fixedly connected to the second-stage reaction inlet pipe (18); the right end of the second-stage reaction inlet pipe (18) is fixedly connected to the second reaction unit cavity (19); the top center of the second reaction unit cavity (19) is fixedly connected to the second-stage reaction outlet pipe (20); and a heat medium inlet (21) is provided at the lower left portion of the second reaction unit cavity (19).

7. A loop microchannel reactor system according to claim 6, characterized in that: A heat medium outlet 2 (22) is provided at the upper right portion of the reaction unit cavity 2 (19), a plurality of layers of mixed fluid microchannel structures (11) are fixedly provided inside the reaction unit cavity 2 (19), a second cyclone mixer (23) is fixedly installed at the bottom end of the reaction unit cavity 2 (19), a second-stage liquid buffer (24) is fixedly installed below the second cyclone mixer (23) inside the reaction unit cavity 2 (19), and a back pressure valve (25) and a second control valve (26) are fixedly installed on the second-stage reaction outlet pipe (20) from left to right.

8. A loop microchannel reactor system according to claim 2, characterized in that: The multi-layer mixed fluid microchannel structure (11) includes: a multi-layer mixed flow channel (27), a mesh flow channel (28), a porous microchannel (29) and a fixed bed flow channel (30), wherein the hydraulic pore size of the internal structure of the multi-layer mixed flow channel (27), the mesh flow channel (28), the porous microchannel (29) and the fixed bed flow channel (30) is 10 μm to 10,000 μm, and the optimal range of the hydraulic pore size is 50 μm to 5,000 μm.

9. A loop microchannel reactor system according to claim 8, characterized in that: A plurality of parallel and spaced flow channel baffles (31) are fixedly provided on the multi-layer mixing flow channel (27), and a fluid channel (3101) is formed between two adjacent parallel and spaced flow channel baffles (31); The mesh flow channel (28) is composed of a plurality of longitudinal baffles (32) and transverse baffles (33) to form a rectangular flow channel (3301), and the connection point between the longitudinal baffles (32) and the transverse baffles (33) is a confluence point; A plurality of irregular flow channel dividers (34) are fixedly provided in the porous microchannel (29), and the plurality of irregular flow channel dividers (34) divide a plurality of three-dimensional porous flow channels (3401).

10. The loop microchannel reactor system according to claim 1, characterized in that: Two or more groups of first-stage reaction mechanisms (1) and second-stage reaction mechanisms (2) can be connected in series through pipelines to realize a cascade continuous reaction. A material inlet and a material outlet are provided on each stage of the reaction mechanism, and the material inlet and the material outlet provide online raw material replenishment and material sampling functions for each stage of the reaction mechanism.

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