Continuous reaction multistage microchannel reactor connected with rectifying tower in series

Abstract

The utility model discloses a continuous reaction multistage micro-channel reactor connected in series with a rectifying tower, which comprises a reaction raw material prefabricating system, a raw material conveying system, a first-stage micro-channel reaction system, a first-stage product rectifying and separating system, a second-stage micro-channel reaction system and a product collecting system, a raw material tank is respectively connected with a micro-channel reactor of the first-stage micro-channel reaction system and a second-stage micro-channel reactor of the second-stage micro-channel reaction system through a metering pump arranged in the raw material conveying system, and the micro-channel reactors are communicated with a rectifying tower of the first-stage product rectifying separation system; the outlet end of the rectifying tower is communicated with the inlet end of the second-stage microchannel reactor, and the outlet end of the second-stage microchannel reactor is communicated with the product collecting system. The continuous reaction device is connected with the rectifying tower in series to realize continuous reaction of materials, can be directly used for industrial production, can replace the original kettle type reaction process, and improves the production efficiency.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical equipment, in particular to a continuous reaction multi-stage microchannel reactor connected in series with a distillation tower. Background Art

[0002] As an important component of microchemical systems, microchannel reactors have sub-millimeter characteristic dimensions, shorter mixing paths, and larger specific surface areas compared to conventional reactors such as intermittent, tubular, and fluidized beds, which greatly promote reaction rates, reduce residence time, and improve selectivity and yield. The internal mixing of microchannel reactors mainly relies on the free diffusion of molecules under low Reynolds numbers. The mixing process is slow, and a longer channel and residence time are required to achieve complete mixing. In order to accurately control the reaction process, it is necessary to achieve good mixing of reactants within a specific flow channel length and reaction time. In order to enhance the mixing effect of microchannel reactors, researchers have proposed various types and structures of passive micromixers, such as stacked plates, obstacles, aggregation-divergence, and curved channels, and have conducted experimental and numerical studies.

[0003] However, current research on microchannel reactors is more focused on the structure of the microchannel reactor itself, and there is less research on the full process equipment involved in actual production. Therefore, designing a microchannel reaction system that can replace the full process of kettle reactors has become an urgent issue to be solved in the industrial transformation and application of microchannel reactors.

[0004] To this end, we designed a continuous reaction multi-stage microchannel reactor connected in series with a distillation tower to solve the above problems. Utility Model Content

[0005] The purpose of the utility model is to solve the shortcomings in the prior art that the research on microchannel reactors is mostly focused on the structure of the microchannel reactors themselves, and lacks research on the full process equipment involved in actual production, and proposes a continuous reaction multi-stage microchannel reactor connected in series with a distillation tower.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A continuous reaction multi-stage microchannel reactor connected in series with a distillation tower, comprising a reaction raw material prefabrication system, a raw material delivery system, a primary microchannel reaction system, a primary product distillation and separation system, a secondary microchannel reaction system and a product collection system, wherein the reaction raw material prefabrication system has a built-in raw material tank, the raw material tank is connected to the microchannel reactor of the primary microchannel reaction system and the secondary microchannel reactor of the secondary microchannel reaction system through a metering pump built into the raw material delivery system, respectively, the microchannel reactor is connected to the distillation tower of the primary product distillation and separation system, the outlet end of the distillation tower is connected to the inlet end of the secondary microchannel reactor, and the outlet end of the secondary microchannel reactor is connected to the product collection system.

[0008] This scheme is further preferred, the raw material tank includes raw material tank one, raw material tank two and raw material tank three, the metering pump includes metering pump one, metering pump two and metering pump three, the raw material tank one and metering pump one, the raw material tank two and metering pump two, and the raw material tank three and metering pump three are all connected through pipelines; wherein, the metering pump one and metering pump two are connected to the inlet end of the microchannel reactor through a pipeline, and the metering pump three is connected to the inlet end of the secondary microchannel reactor.

[0009] In the present solution, it is further preferred that the pipelines connecting the inlet and outlet ends of the metering pump 1 and the metering pump 2 are covered with a diaphragm sleeve.

[0010] This scheme is further preferred, a metering pump four is provided on the pipeline connecting the microchannel reactor and the distillation tower, and a metering pump five is provided on the pipeline connecting the outlet end of the distillation tower and the inlet end of the secondary microchannel reactor.

[0011] In the present embodiment, a metering pump 6 is provided on the pipeline connecting the outlet end of the secondary microchannel reactor and the product collection system.

[0012] In a further preferred embodiment of the present invention, the product collection system has a built-in cooling tower, a crystallization tower or an extraction tower.

[0013] The present solution is further preferred in that the inlet and outlet ends of the microchannel reactor and the secondary microchannel reactor are both provided with spherical connecting valves, and the reaction channels in the microchannel reactor and the secondary microchannel reactor are both heart-shaped pipeline structures.

[0014] In the present embodiment, the distillation tower is further provided with multiple layers of tower plates, and each layer of the tower plates is provided with a spherical connecting valve.

[0015] Compared with the prior art, the utility model has the following beneficial effects: the utility model realizes continuous reaction of materials by connecting the distillation tower in series, and the equipment can be directly used for industrial production, has strong applicability, can replace the original kettle reaction process, and improves production efficiency. At the same time, since each layer of the distillation tower can be connected to the microchannel reactor, the applicability of the equipment is increased, and the industrial practical application of the microchannel reactor is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a connection schematic diagram of a continuous reaction multi-stage microchannel reactor connected in series with a distillation tower proposed by the utility model.

[0017] The numbers in the figure are: 1. Raw material tank one; 2. Raw material tank two; 3. Metering pump one; 4. Metering pump two; 5. Microchannel reactor; 6. Metering pump four; 7. Distillation tower; 8. Metering pump five; 9. Raw material tank three; 10. Metering pump three; 11. Secondary microchannel reactor; 12. Metering pump six; 13. Extraction tower. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0019] Example 1: This example proposes a continuous reaction multi-stage microchannel reactor connected in series with a distillation tower, referring to Figure 1 The equipment mainly includes a reaction raw material prefabrication system A, a raw material transportation system B, a primary microchannel reaction system C, a primary product distillation and separation system D, a secondary microchannel reaction system E and a product collection system F.

[0020] The reaction raw material prefabrication system A is mainly used for processing raw materials, such as heating or cooling. A raw material tank is built in the reaction raw material prefabrication system A, and the material is heated or cooled through the raw material tank. The raw material tank is connected to the microchannel reactor 5 of the primary microchannel reaction system and the secondary microchannel reactor 11 of the secondary microchannel reaction system through the metering pump built in the raw material conveying system. The raw material tank and the stirring paddle used for stirring the material in the raw material tank are made of high temperature resistant, low temperature resistant and corrosion resistant polytetrafluoroethylene material, and the stirring speed of the stirring paddle can reach 5000 r / min. Specifically, the above-mentioned raw material tank includes raw material tank 1, raw material tank 2 and raw material tank 3 9; the above-mentioned metering pump includes metering pump 1 3, metering pump 2 4 and metering pump 3 10.

[0021] The raw material tank 1 and the metering pump 1 3, the raw material tank 2 and the metering pump 2 4, and the raw material tank 3 9 and the metering pump 3 10 are all connected through pipelines. Among them, the metering pump 1 3 and the metering pump 2 4 are connected to the inlet end of the microchannel reactor 5 through a pipeline, and the metering pump 3 10 is connected to the inlet end of the secondary microchannel reactor 11.

[0022] In order to ensure the temperature of the raw materials in the conveying system, the pipelines connecting the inlet and outlet ends of metering pump 1 3 and metering pump 2 4 are covered with a diaphragm sleeve with a heat preservation function.

[0023] The microchannel reactor 5 is connected to the distillation tower 7 of the primary product distillation separation system, the outlet end of the distillation tower 7 is connected to the inlet end of the secondary microchannel reactor 11, and the outlet end of the secondary microchannel reactor 11 is connected to the product collection system, and the product collection system is built-in with any one of a cooling tower, a crystallization tower or an extraction tower, which is confirmed according to the specific reaction. If the product only needs to be cooled, a cooling tower is selected, if the product needs to be crystallized, a crystallization tower is selected, and if the product needs to be extracted, an extraction tower is selected. In this embodiment, the extraction tower 13 is taken as an example for description.

[0024] A metering pump 296 is provided on the pipeline connecting the microchannel reactor 5 and the distillation tower 7, and a metering pump 58 is provided on the pipeline connecting the outlet end of the distillation tower 7 and the inlet end of the secondary microchannel reactor 11. A metering pump 612 is provided on the pipeline connecting the outlet end of the secondary microchannel reactor 11 and the product collection system.

[0025] The inlet and outlet ends of the microchannel reactor 5 and the secondary microchannel reactor 11 are both provided with spherical connecting valves, and the reaction channels in the microchannel reactor 5 and the secondary microchannel reactor 11 are both heart-shaped pipeline structures, and the cavity is a plate structure, which can be disassembled and assembled according to actual needs. The material is silicon carbide material, and each plate has a sampling valve and a heat exchange channel. Commercial microchannel reactors are generally plate structures, and the reaction plate can be directly inserted into the cavity of the microchannel reactor to install the reaction plate, and the commercial microchannel reactor has a heat exchange pipeline, and the heat exchange pipeline of the equipment inside can be preheated. In the technical field, the self-structure of the microchannel reactor is a mature technology, and the internal structure of the microchannel reactor 5 and the secondary microchannel reactor 11 will no longer be described in detail in this scheme.

[0026] The distillation tower 7 is provided with multiple layers of tower plates, each of which is provided with a ball connecting valve, and the tower plates of any layer in the distillation tower 7 are connected to the microchannel reactor 5 and the secondary microchannel reactor 11 through the ball connecting valve.

[0027] Example 2: This example verifies the performance of the continuous reaction multi-stage microchannel reactor connected in series with the distillation tower proposed in Example 1 through actual operation. The specific operation method is as follows:

[0028] Inject 1 mol of ethylbenzene into raw material tank 1, preheat the temperature to 200°C, and stir at a speed of 1000 r / min.

[0029] Inject 1 mol of propylene and 2 g of anhydrous aluminum chloride into raw material tank 2, preheat the temperature to 100°C, and stir at a speed of 500 r / min.

[0030] The microchannel reactor 5 is preheated to 100°C, metering pump 1 3 and metering pump 2 4 are turned on, ethyl peroxide, propylene and catalyst aluminum chloride are pumped into the microchannel reactor 5, 4 plates are added to the microchannel reactor 5, and the product obtained by the reaction is pumped into the distillation tower 7 through the metering pump 4 6 to start distillation separation.

[0031] After the distillation separation is completed, the inlet pipeline of the metering pump five 8 is connected to the 10th tower plate of the distillation tower 7, and the distillate, i.e., styrene, is pumped into the secondary microchannel reactor 11. The secondary microchannel reactor 11 is preheated to 80°C in advance, 20g of emulsifier is added to water to make an emulsion, which is injected into the raw material tank three 9 with a stirring speed of 2000 r / min, and is pumped into the secondary microchannel reactor 11 through the metering pump three 10. The secondary microchannel reactor 11 is equipped with 6 plates; the reaction product is pumped into the extraction tower 13 pre-loaded with 300ml of 95 ethanol through the metering pump six 12, the chromatographic solid is removed, and the polystyrene microspheres are obtained by drying, and a scanning electron microscope test is performed.

[0032] Example 3: This example further verifies the performance of the continuous reaction multi-stage microchannel reactor connected in series with the distillation tower proposed in Example 1 by adjusting the operation mode. The specific operation mode is as follows:

[0033] Inject 0.5 mol of ethylbenzene into raw material tank 1, preheat the temperature to 100°C, and stir at a speed of 1000 r / min.

[0034] Inject 1 mol of propylene and 2 g of anhydrous aluminum chloride into raw material tank 2, preheat the temperature to 100°C, and stir at a speed of 500 r / min.

[0035] The microchannel reactor 5 is preheated to 80°C, metering pump 1 3 and metering pump 2 4 are turned on, ethyl peroxide, propylene and catalyst aluminum chloride are pumped into the microchannel reactor 5, and 4 plates are added to the microchannel reactor 5. The product obtained by the reaction is pumped into the distillation tower 7 through the metering pump 2 6 to start distillation separation.

[0036] After the distillation separation is completed, the inlet pipeline of the metering pump five 8 is connected to the 10th tower plate of the distillation tower 7, and the distillate, i.e., styrene, is pumped into the secondary microchannel reactor 11. The secondary microchannel reactor 11 is preheated to 50°C in advance, 15g of emulsifier is added to water to make an emulsion, which is injected into the raw material tank three 9 with a stirring speed of 2000 r / min, and is pumped into the secondary microchannel reactor 11 through the metering pump three 10. The secondary microchannel reactor 11 is equipped with 5 plates; the reaction product is pumped into the extraction tower 13 pre-loaded with 300ml of 95 ethanol through the metering pump six 12, the chromatographic solid is removed, and the polystyrene microspheres are obtained by drying, and a scanning electron microscope test is performed.

[0037] In Example 2 and Example 3, two different specific process operations are used, and the products are also two different microspheres with obvious difference in particle size (under the same 1 μm scale, the particle size of the product of Example 3 is obviously smaller than that of the product of Example 2). Examples 2 and 3 show that the continuous reaction multi-stage microchannel reactor connected in series with the distillation tower proposed in this scheme can be directly used for industrial production and has wide applicability.

[0038] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A continuous reaction multistage microchannel reactor connected in series with a distillation tower, characterized in that: The invention comprises a reaction raw material prefabrication system, a raw material delivery system, a primary microchannel reaction system, a primary product distillation and separation system, a secondary microchannel reaction system and a product collection system. The reaction raw material prefabrication system has a built-in raw material tank, and the raw material tank is connected to a microchannel reactor (5) of the primary microchannel reaction system and a secondary microchannel reactor (11) of the secondary microchannel reaction system through a metering pump built into the raw material delivery system, respectively. The microchannel reactor (5) is connected to a distillation tower (7) of the primary product distillation and separation system, the outlet end of the distillation tower (7) is connected to the inlet end of the secondary microchannel reactor (11), and the outlet end of the secondary microchannel reactor (11) is connected to the product collection system.

2. A continuous reaction multi-stage microchannel reactor connected in series with a distillation tower according to claim 1, characterized in that: The raw material tank comprises a raw material tank 1 (1), a raw material tank 2 (2) and a raw material tank 3 (9); the metering pump comprises a metering pump 1 (3), a metering pump 2 (4) and a metering pump 3 (10); the raw material tank 1 (1) and the metering pump 1 (3), the raw material tank 2 (2) and the metering pump 2 (4), and the raw material tank 3 (9) and the metering pump 3 (10) are all connected via pipelines; wherein the metering pump 1 (3) and the metering pump 2 (4) are connected to the inlet end of the microchannel reactor (5) via a pipeline, and the metering pump 3 (10) is connected to the inlet end of the secondary microchannel reactor (11).

3. A continuous reaction multi-stage microchannel reactor connected in series with a distillation tower according to claim 2, characterized in that: The pipelines connecting the inlet and outlet ends of the metering pump 1 (3) and the metering pump 2 (4) are covered with a diaphragm sleeve.

4. The continuous reaction multi-stage microchannel reactor connected in series with a distillation tower according to claim 1, characterized in that: A metering pump four (6) is provided on the pipeline connecting the microchannel reactor (5) and the distillation tower (7), and a metering pump five (8) is provided on the pipeline connecting the outlet end of the distillation tower (7) and the inlet end of the secondary microchannel reactor (11).

5. The continuous reaction multi-stage microchannel reactor connected in series with a distillation tower according to claim 1, characterized in that: A metering pump six (12) is provided on a pipeline connecting the outlet end of the secondary microchannel reactor (11) and the product collection system.

6. The continuous reaction multi-stage microchannel reactor connected in series with a distillation tower according to claim 1, characterized in that: The product collection system has any one of a cooling tower, a crystallization tower or an extraction tower built in.

7. The continuous reaction multi-stage microchannel reactor connected in series with a distillation tower according to claim 1, characterized in that: The inlet and outlet ends of the microchannel reactor (5) and the secondary microchannel reactor (11) are both provided with spherical connecting valves, and the reaction channels in the microchannel reactor (5) and the secondary microchannel reactor (11) are both heart-shaped pipeline structures.

8. The continuous reaction multi-stage microchannel reactor connected in series with a distillation tower according to claim 1, characterized in that: The distillation tower (7) is provided with multiple layers of tower plates, and each layer of the tower plates is provided with a spherical connecting valve.

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