Microchannel reactor for exothermic reactions

Abstract

This invention discloses a microchannel reactor for exothermic reactions, comprising a reaction layer in which reaction microchannels with reactant inlets and product outlets are configured. The reactant inlets include a first inlet for introducing a first reactant into the reaction microchannel and a second inlet for introducing a second reactant into the reaction microchannel. The reaction layer further includes an ejector structure comprising: an ejector medium inlet for introducing an ejector medium; a Venturi channel extending from the ejector medium inlet and having a nozzle facing the first inlet; and a drainage channel extending from the second inlet and communicating with the Venturi channel. Thus, the ejector medium from the ejector medium inlet introduces the second reactant from the second inlet into the Venturi channel when flowing through it, and disperses and mixes the second reactant with the first reactant when sprayed from the nozzle toward the first reactant from the first inlet.

Description

Technical Field

[0001] This invention relates to the field of microchannel reaction technology, and more particularly to a microchannel reactor for exothermic reactions. Background Technology

[0002] As is well known, for strongly exothermic reactions such as nitration, a dedicated batch reactor (e.g., a batch nitrator) is typically used as the reaction vessel. To suppress the instantaneous release of heat at the beginning of the reaction and prevent local overheating that could lead to decomposition or explosion, a series of enhanced temperature control measures are comprehensively implemented inside the batch reactor. For example, a large number of heat exchange pipes are installed to increase the heat dissipation area; mechanical or pneumatic stirring is used to enhance mixing and heat dissipation; a certain amount of reaction liquid is reserved in the reactor to absorb and buffer the large amount of heat released at the beginning of the reaction; and some equipment is also equipped with a spray function to disperse the addition of reactants, which is more conducive to initial temperature control.

[0003] However, batch reactors, as reaction vessels, still have the following typical drawbacks:

[0004] 1. Large liquid hold-up and high safety risk: A large volume of reaction liquid needs to be maintained in a batch reactor to achieve dilution and buffering. Once runaway decomposition occurs, its destructive force is huge, and the risk of explosion is significantly higher than that of continuous flow equipment.

[0005] 2. Significant scale-up effect: The process parameters of the batch reactor are difficult to be directly scaled up to the industrial production scale. During the scale-up process, the heat and mass transfer conditions change, which can easily lead to an increase in side reactions or temperature runaway. The research and development cycle is long and the cost is high.

[0006] 3. Backmixing of materials and increased by-products: Backmixing of new and old materials occurs in the batch reactor. Some reacted products are mixed with unreacted raw materials for a long time, which may lead to over-reaction or other side reactions, affecting the purity of the product.

[0007] 4. Large equipment footprint: To meet the requirements of heat dissipation and liquid holding capacity, the batch reactor is large in size, which places high demands on the plant and supporting facilities.

[0008] Microchannel reactors, developed based on continuous flow technology, are considered a viable alternative to batch reactors due to their advantages such as narrow channels, large specific surface area, low liquid holdup, no scale-up effect, and no backmixing. However, when applied to instantaneously exothermic reactions, traditional microchannel reactors still exhibit the following significant technical problems:

[0009] 1. Strong heat release at the front end and temperature control failure: In traditional microchannels, once the reactants are mixed, most of the reaction can be completed in a short channel section and time at the inlet (e.g., channel section about 5-10cm, reaction time about 1-2 seconds). Because the channel section where the reaction occurs is narrow and short, the heat generated by the reaction cannot be diffused through the channel wall in time, causing the material to rise rapidly to a high temperature (e.g., the temperature rises rapidly to above 70°C). The instantaneous high temperature can easily cause the material to decompose, which may result in a large amount of flue gas, a sudden increase in system pressure, and excessive nitrogen content in the product, or even an explosion that damages the equipment.

[0010] 2. Problem of excessively high and drastic fluctuations in reaction pressure: To enhance heat dissipation, traditional microchannel processes often require increased material flow rates, leading to a significant increase in inlet pressure. This is especially true when the reaction products are high-viscosity oily substances (such as mixed esters), requiring high pressures (e.g., 4-5 MPa) to maintain a stable flow rate, placing stringent demands on the pressure resistance of the pump, piping, and module itself. Furthermore, if localized overheating occurs at the front end, generating fumes, the pressure within the channel will fluctuate drastically and instantaneously, causing flow rate instability. For reactions involving energetic materials, this sudden pressure increase further amplifies safety risks. If the reactor is supported by non-metallic materials (such as silicon carbide or glass), the non-metallic microchannels cannot withstand instantaneous pressure fluctuations, easily leading to reactor rupture. While metallic microchannels can withstand high pressure, long-term operation under high-pressure fluctuations still presents risks of leakage and fatigue failure. Summary of the Invention

[0011] To address the aforementioned technical problems in the prior art, embodiments of the present invention provide a microchannel reactor for exothermic reactions.

[0012] To solve the above-mentioned technical problems, the technical solution adopted in the embodiments of the present invention is as follows:

[0013] A microchannel reactor for an exothermic reaction includes a reaction layer in which reaction microchannels with reactant inlets and product outlets are configured. The reactant inlets include a first inlet for introducing a first reactant into the reaction microchannel and a second inlet for introducing a second reactant into the reaction microchannel. The reaction layer further includes an ejector structure comprising:

[0014] Ejector medium inlet, which is used to introduce the ejector medium;

[0015] A Venturi channel, which extends from the ejector medium inlet and has an ejection port facing the first inlet;

[0016] The inlet channel extends from the second inlet and connects to the Venturi channel, thereby introducing the second reactant from the second inlet into the Venturi channel as the inlet flows through it, and dispersing and mixing the second reactant with the first reactant as it is ejected from the nozzle toward the first reactant from the first inlet.

[0017] Preferably, a reserved liquid-holding cavity is provided between the injection port of the venturi channel and the first inlet.

[0018] Preferably, the first inlet includes a plurality of micro-inlets all facing the injection port of the Venturi channel, the plurality of micro-inlets being used to disperse the first reactant.

[0019] Preferably, two drainage channels are led out from the first inlet; wherein:

[0020] The two drainage channels are located on both sides of the Venturi channel and are laterally connected to the Venturi channel on both sides.

[0021] Preferably,

[0022] The ejector structure includes multiple ejector structures arranged in parallel.

[0023] Both the first inlet and the second inlet include multiple inlets, and each ejector structure corresponds to one first inlet and one second inlet.

[0024] Preferably, the microchannel reactor for the exothermic reaction further comprises two heat exchange layers located on both sides of the reaction layer, each heat exchange layer having a heat exchange medium inlet and a heat exchange medium outlet; the flow direction of the heat exchange medium in the heat exchange microchannel is opposite to the flow direction of the fluid in the reaction microchannel.

[0025] Preferably, the microchannel reactor for the exothermic reaction comprises a sealing plate, a first substrate, a second substrate, and a third substrate stacked sequentially from front to back; the first substrate and the second substrate define the reaction layer, the sealing plate and the first substrate define the heat exchange layer located in front of the reaction layer, and the second substrate and the third substrate define the heat exchange layer located behind the reaction layer; wherein:

[0026] The sealing plate and / or the third substrate are provided with at least: a first reactant supply interface connected to the first inlet for supplying the first reactant, a second reactant supply interface connected to the second inlet for supplying the second reactant, a product outlet interface connected to the product outlet for exporting the reaction product, and an ejector medium supply interface connected to the ejector medium inlet for supplying the ejector medium.

[0027] A second reactant supply channel is constructed between the second reactant supply interface and the second inlet, and an ejector medium supply channel is constructed between the ejector medium supply interface and the ejector medium inlet.

[0028] The main body of the second reactant supply channel and the main body of the ejector medium supply channel are not located on the same layer as the reaction layer.

[0029] Preferably, the second reactant supply channel is located in the same layer as the heat exchange layer on the rear side of the reaction layer, and the ejector medium supply channel is located in the same layer as the heat exchange layer on the front side of the reaction layer;

[0030] or

[0031] The ejector medium supply channel is located in the same layer as the heat exchange layer on the rear side of the reaction layer, and the second reactant supply channel is located in the same layer as the heat exchange layer on the front side of the reaction layer.

[0032] Preferably, the sealing plate and / or the third substrate further comprises: a heat exchange medium supply interface communicating with the heat exchange medium inlet for supplying heat exchange medium, and a heat exchange medium outlet interface communicating with the heat exchange medium outlet for discharging heat exchange medium; wherein:

[0033] The first reactant supply interface, the second reactant supply interface, the ejector medium supply interface, the product outlet interface, the heat exchange medium supply interface, and the heat exchange medium outlet interface are arranged in the area of ​​the sealing plate near the same side.

[0034] Preferably, the reaction microchannel is used for nitration reaction.

[0035] Compared with the prior art, the beneficial effects of the microchannel reactor for exothermic reactions disclosed in this invention are:

[0036] 1. The inert fluid (i.e., the ejector medium, hereinafter referred to as the inert fluid) is premixed with the second reactant and the second reactant is pre-diluted, thereby reducing the instantaneous contact amount between the second reactant and the first reactant, which can reduce the heat of reaction at the moment of contact.

[0037] 2. The mixture of inert fluid and second reactant is atomized using a Venturi channel, thereby fully dispersing the second reactant and avoiding localized instantaneous heat release caused by the reaction of the second reactant with the first reactant in an undispersed state.

[0038] 3. When the inert gas flows through the Venturi channel, it will attract the second reactant in the drainage channel. Therefore, the Venturi effect can serve as part of the driving force for supplying the second reactant, thereby significantly reducing the pressure on the second reactant from the pump head used to supply it, and thus reducing the requirements for the pump head's pressure resistance parameters.

[0039] 4. Inert fluids can absorb some of the heat released by the reaction, thereby further suppressing the instantaneous temperature rise in the inlet section.

[0040] 5. Inert fluids dilute high-viscosity second reactants and high-viscosity products, thereby improving the fluidity of reactants and products. This allows reactants and products to flow rapidly to other sections of the reaction microchannel downstream of the inlet section, so that the exothermic reaction process is no longer concentrated in the inlet section, but also takes place in other sections, thereby further suppressing the temperature rise in the inlet section.

[0041] 6. The temperature in the inlet section is suppressed, which effectively suppresses the generation of nitrous oxide in the inlet section, thereby suppressing pressure fluctuations caused by nitrous oxide and flow rate fluctuations caused by pressure fluctuations.

[0042] 7. Because pressure fluctuations in the inlet section are suppressed, the reactor can be made of glass material with lower pressure resistance.

[0043] 8. In this invention, the dispersion of reactants is achieved within a smaller microchannel, thereby enabling the microchannel reactor to have the dispersion function of a batch reactor.

[0044] 9. The second reactant supply channel and the ejector medium supply channel are not located at the same level as the reaction layer, but are located on the front and rear sides of the reaction layer, respectively. In this way, the reaction layer does not need to reserve a special area for the second reactant supply channel and the ejector medium supply channel, thus allowing the reaction microchannels to be configured in the areas corresponding to the reaction layer and the two channels, thereby increasing the area ratio occupied by the reaction microchannels.

[0045] It should be understood that the foregoing general description and the following detailed description are exemplary and illustrative only, and are not intended to limit the invention.

[0046] The overview of various implementations or examples of the technology described in this invention is not a complete disclosure of the full scope or all features of the disclosed technology. Attached Figure Description

[0047] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with or without letter suffixes may indicate different instances of similar parts. The drawings generally illustrate various embodiments by way of example rather than limitation and, together with the description and claims, serve to explain embodiments of the invention. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method.

[0048] Figure 1 This is a front view of the microchannel reactor for exothermic reactions provided by the present invention.

[0049] Figure 2 This is a front view of the first substrate in the microchannel reactor for exothermic reactions provided by the present invention.

[0050] Figure 3 This is a front view of the second substrate in the microchannel reactor for exothermic reactions provided by the present invention.

[0051] Figure 4 This is a front view of the third substrate in the microchannel reactor for exothermic reactions provided by the present invention.

[0052] Figure 5 This is an exploded view of the microchannel reactor for exothermic reactions provided by the present invention.

[0053] Figure label:

[0054] 10-First substrate; 20-Second substrate; 30-Third substrate; 40-Sealing plate; 50-Reaction microchannel; 511-First inlet; 5111-First reactant supply interface; 5112-First reactant supply channel; 512-Second inlet; 5121-Second reactant supply interface; 5122-Second reactant supply channel; 52-Product outlet; 521-Product outlet; 53-Ejector structure; 531-Ejector medium inlet; 532-Venturi channel; 5321-Jet nozzle; 533-Drainage channel; 534-Liquid holding chamber; 54-Ejector medium supply interface; 61-Front heat exchange layer; 62-Rear heat exchange layer; 63-Heat exchange medium inlet; 64-Heat exchange medium outlet. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0056] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0057] To keep the following description of the embodiments of the present invention clear and concise, detailed descriptions of known functions and known components are omitted.

[0058] An embodiment of the present invention discloses a microchannel reactor suitable for exothermic reactions, especially for strongly exothermic reactions in which the reactants and / or products have high viscosity, such as the nitration reaction in which glycerol (high viscosity) reacts with nitric acid to produce nitroglycerin (high viscosity).

[0059] like Figure 5 and combined Figure 3 As shown, the reactor includes a roughly rectangular plate-shaped body, within which a layer of microchannels is configured to provide a reaction site. These microchannels may be referred to as reaction microchannels 50, and the layer containing reaction microchannels 50 may be referred to as the reaction layer.

[0060] The reaction microchannel 50 has a reactant inlet and a product outlet 52. The reactant inlet and product outlet are far apart. For example, the reactant inlet is located in the region near the bottom of the plate-like body, and the product outlet 52 is located in the region near the top of the plate-like body. The reactant inlet includes a first inlet 511 and a second inlet 512. The first inlet 511 is used to introduce a first reactant into the reaction microchannel 50, and the second inlet 512 is used to introduce a second reactant into the reaction microchannel 50. The first reactant is a reactant for an exothermic reaction, such as an acid solution, specifically nitric acid. The second reactant is a reactant for an exothermic reaction, such as glycerol. After the first reactant and the second reactant enter the reaction microchannel 50, they come into contact and undergo an exothermic reaction, such as a nitration reaction. The product of the nitration reaction can be a highly viscous substance such as nitroglycerin.

[0061] In this invention, an ejector structure 53 is configured between the first inlet 511 and the second inlet 512. The ejector structure 53 includes an ejector medium inlet 531, a Venturi channel 532, and a drainage channel 533. The Venturi channel 532 extends from the ejector medium inlet 531 toward the first inlet 511, and its distal end forms a jet nozzle 5321 facing the first inlet 511. The drainage channel 533 extends from the second inlet 512 and penetrates to the cross-sectional contraction section of the Venturi channel 532. The ejector medium inlet 531 is used to introduce the ejector medium, which is an inert fluid that does not react with the two reactants and the product. The ejector medium can be a fluid that is miscible or insoluble with the reactants and product. The ejector medium can be a liquid or a gas, specifically, for example, nitrogen or dichloromethane. The ejector medium from the ejector medium inlet 531 then flows through the constriction section of the Venturi channel 532. While flowing through the constriction section, the second reactant from the second inlet 512 is drawn into the Venturi channel 532 through the flow channel 533 based on the Venturi effect and mixed with the ejector medium. Subsequently, both are ejected simultaneously from the nozzle 5321 of the Venturi channel 532. During the ejection process, the mixture is atomized, thereby dispersing the mixture. The atomized mixture of ejector medium and second reactant ejected from the nozzle 5321 comes into contact with the first reactant from the first inlet 511 and undergoes an exothermic reaction such as nitration. During the reaction, the mixture mainly flows along the reaction microchannel 50 by means of the pumping action of the pump head used to transport the first reactant. After most of the reaction is completed, the mixture finally flows out from the product outlet 52.

[0062] The advantage of configuring the ejector structure 53 at the first inlet 511 and the second inlet 512 in this invention is that:

[0063] 1. The inert fluid (i.e., the ejector medium, hereinafter referred to as the inert fluid) is premixed with the second reactant and the second reactant is pre-diluted, thereby reducing the instantaneous contact amount between the second reactant and the first reactant, which can reduce the heat of reaction at the moment of contact.

[0064] 2. The mixture of inert fluid and second reactant is atomized using the Venturi channel 532, thereby fully dispersing the second reactant and avoiding localized instantaneous heat release caused by the reaction of the second reactant with the first reactant in an undispersed state.

[0065] 3. When the inert gas flows through the Venturi channel 532, it will attract the second reactant in the drainage channel 533. Therefore, the Venturi effect can serve as part of the driving force for supplying the second reactant, thereby significantly reducing the pressure of the pump head on the second reactant and thus reducing the requirements for the pressure resistance parameters of the pump head.

[0066] 4. Inert fluids can absorb some of the heat released by the reaction, thereby further suppressing the instantaneous temperature rise in the inlet section.

[0067] 5. Inert fluids dilute high-viscosity second reactants and high-viscosity products, thereby improving the fluidity of reactants and products. This allows reactants and products to flow rapidly to other sections of the reaction microchannel 50 downstream of the inlet section, so that the exothermic reaction process is no longer concentrated in the inlet section, but also takes place in other sections, thereby further suppressing the temperature rise in the inlet section.

[0068] 6. The temperature in the inlet section is suppressed, which effectively suppresses the generation of nitrous oxide in the inlet section, thereby suppressing pressure fluctuations caused by nitrous oxide and flow rate fluctuations caused by pressure fluctuations.

[0069] 7. Because pressure fluctuations in the inlet section are suppressed, the reactor can be made of glass material with lower pressure resistance.

[0070] 8. In this invention, the dispersion of reactants is achieved within a smaller microchannel, thereby enabling the microchannel reactor to have the dispersion function of a batch reactor.

[0071] In some preferred configurations, each first inlet 511 includes a plurality of micro-inlets all facing the nozzle 5321 of the Venturi channel 532, the micro-inlets being used to disperse the first reactant; a reserved liquid-holding cavity 534 is configured between the first inlet 511 and the nozzle 5321 of the Venturi channel. The second reactant, dispersed by the ejector medium ejected from the nozzle 5321, comes into contact with the second reactant flowing out of the first inlet 511 and dispersed by the plurality of micro-inlets in the reserved liquid-holding cavity 534. The reserved liquid-holding cavity 534 provides greater space for the exothermic reaction, thereby further suppressing excessive temperature caused by instantaneous exothermic reaction.

[0072] In some preferred structures, the second inlet 512 is located directly above the first inlet 511, the ejector medium inlet 531 is located below and adjacent to the second inlet 512, the Venturi channel 532 extends vertically downward from the ejector medium inlet 531, and two drainage channels 533 are drawn out from the second inlet 512. The two drainage channels 533 are located on both sides of the Venturi channel 532 and are adjacent to the Venturi channel 532, and extend laterally to the constriction section of the Venturi channel 532. The periphery of the drainage channels 533 is arranged with reaction microchannels 50 structures. This configuration makes the ejector structure 53 compact and occupies a relatively small area of ​​the reaction layer, thereby increasing the area occupied by the microchannels.

[0073] In some preferred structures, multiple ejector structures 53 are arranged in the reaction layer, and each ejector structure 53 extends along... Figure 3The ejector structures 53 are arranged side-by-side and connected in the left-right direction. Each ejector structure 53 corresponds to a first inlet 511 and a second inlet 512 in the above arrangement, thereby improving the efficiency of reactant supply and product preparation. Preferably, each first inlet 511 and each second inlet 512 is powered by only one pump head. Thus, since each ejector structure 53 can provide partial power, the pressure applied by the pump head to deliver the second reactant can be significantly reduced.

[0074] In some preferred structures, such as Figure 2 , Figure 4 and combined Figure 5 As shown, the plate-shaped main body is also equipped with two heat exchange layers for heat exchange with the reaction microchannel 50. The two heat exchange layers are located on the front and rear sides of the reaction layer, respectively. The front heat exchange layer 61 and the rear heat exchange layer 62 are each equipped with a microchannel with a heat exchange medium inlet 63 and a heat exchange medium outlet 64. These microchannels can be referred to as heat exchange microchannels. By arranging a pump head on the periphery of the plate-shaped main body between the heat exchange medium inlet 63 and the heat exchange medium outlet 64, the heat exchange medium can be continuously introduced into the heat exchange microchannel through the heat exchange medium inlet 63 and flow out through the heat exchange medium outlet 64. The overall flow direction of the heat exchange medium in the heat exchange layer is opposite to the flow direction of the fluid (including reactants, reaction products, and inert fluid) in the reaction layer, thereby improving the fluid heat exchange and cooling effect of each section of the reaction microchannel 50.

[0075] In some preferred structures, such as Figure 1 and combined Figure 5 As shown, the interfaces for connecting to external pipelines are all arranged on the same side of the plate-shaped body. Specifically, the interfaces include: a first reactant supply interface 5111 attached to the first reactant supply pipeline for providing the first reactant to the first inlet 511; a second reactant supply interface 5121 attached to the second reactant supply pipeline for providing the second reactant to the second inlet 512; a product outlet interface 521 attached to the product conveying pipeline for discharging the reaction product at the product outlet 52; an ejector interface supply interface attached to the ejector medium supply pipeline for providing inert fluid to the ejector medium; the aforementioned heat exchange medium inlet 63 and heat exchange medium outlet 64.

[0076] like Figure 3 As shown, a first reactant supply channel 5112 is constructed between the first reactant supply interface 5111 and the first inlet 511. The first reactant supply channel 5112 extends along the bottom of the plate-shaped body and forms multiple branches to connect to each of the first inlets 511; as Figure 4As shown, a second reactant supply channel 5122 is constructed between the second reactant supply interface 5121 and the second inlet 512. The second reactant supply channel 5122 extends laterally and forms multiple branches to connect to each of the second inlets 512, as shown. Figure 2 As shown, an ejector medium supply channel is constructed between the ejector medium supply interface 54 and the ejector medium inlet 531. The ejector medium supply channel extends laterally and forms multiple branches to connect to each ejector medium inlet 531.

[0077] In this invention, the second reactant supply channel 5122 and the ejector medium supply channel are not configured at the same level as the reaction layer, but are configured on the front and rear sides of the reaction layer, respectively. Thus, the reaction layer does not need to reserve a special area for configuring the second reactant supply channel 5122 and the ejector medium supply channel, thereby allowing the reaction microchannels 50 to be configured in both the reaction layer and the areas corresponding to the two channels, thereby increasing the area ratio occupied by the reaction microchannels 50.

[0078] In this invention, the reaction layer and heat exchange layer in the plate-shaped main body are defined and formed by stacking multiple plate units. Specifically, the plate-shaped main body is formed by stacking a sealing plate 40, a first substrate 10, a second substrate 20, and a third substrate 30 sequentially from front to back. The stacking of each plate can be fixed by sintering and bonding at the sides of the plates. The reaction microchannel 50, the ejector structure 53, and the first reactant supply channel 5112 are all formed on the front plate surface of the second substrate 20. The heat exchange microchannel in the rear heat exchange layer 62 is formed on the front plate surface of the third substrate 30, and the heat exchange microchannel in the front heat exchange layer 61 is formed on the front plate surface of the first substrate 10. The aforementioned interfaces are disposed on the sealing plate 40 and the third substrate 30, specifically, as shown in the figure. Figure 1 As shown, the first reactant supply interface 5111, the product outlet interface 521, the ejector medium supply interface 54, the heat exchange medium inlet 63, and the heat exchange medium outlet 64 are all disposed on the sealing plate 40, and the second reactant supply interface 5121 is disposed on the third substrate 30. Preferably, the second reactant supply interface 5121 and the ejector medium supply interface 54 are located approximately in the same area.

[0079] The ejector medium supply channel is formed on the front surface of the first substrate 10, at the same level as the front heat exchange layer 61. The ejector medium supply interface 54 only needs to penetrate the sealing plate 40 to communicate with the proximal end of the ejector medium supply channel. At the end of each branch of the ejector medium supply channel, a through hole is formed at a position opposite to the proximal end of the Venturi channel 532 of the ejector structure 53 on the second substrate 20, allowing inert flow in the ejector medium supply channel to enter the Venturi channel 532. Thus, the through hole serves as the ejector medium inlet 531. The second reactant supply channel 5122 is formed on the front surface of the third substrate 30, at the same level as the rear heat exchange layer 62. The second reactant supply interface 5121 on the third substrate 30 only needs to penetrate the third substrate 30 to communicate with the second reactant supply channel 5122. Each second inlet 512 communicates with each branch of the second reactant supply channel 5122 by penetrating the second substrate 20. The arrangement of the ejector medium supply channel and the second reactant supply channel 5122 described above allows for a larger proportion of the reaction layer area occupied by the reaction microchannel 50.

[0080] Furthermore, although exemplary embodiments have been described in this invention, their scope includes any and all embodiments based on the invention that have equivalent elements, modifications, omissions, combinations (e.g., schemes involving intersections of various embodiments), adaptations, or alterations. Elements in the claims will be interpreted broadly based on the language used in the claims and are not limited to the examples described in this specification or during the implementation of this application, and such examples will be interpreted as non-exclusive. Therefore, this specification and examples are intended to be considered illustrative only, and the true scope and spirit are indicated by the following claims and the full scope of their equivalents.

[0081] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more of them) can be used in combination with each other. Other embodiments may be used by those skilled in the art upon reading the above description. Furthermore, in the above detailed description, various features may be grouped together to simplify the invention. This should not be construed as an intention that a disclosed feature, which is not claimed, is necessary for any claim. Rather, the subject matter of the invention may be less than all the features of the particular disclosed embodiment. Thus, the following claims are incorporated herein by reference as examples or embodiments, wherein each claim is independently considered as a separate embodiment, and these embodiments are contemplated as being possible in various combinations or arrangements. The scope of the invention should be determined by reference to the appended claims and the full scope of their equivalents.

[0082] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. A microchannel reactor for an exothermic reaction, comprising a reaction layer in which reaction microchannels with reactant inlets and product outlets are configured, the reactant inlets including a first inlet for introducing a first reactant into the reaction microchannel and a second inlet for introducing a second reactant into the reaction microchannel, characterized in that, The reaction layer further includes an ejector structure, the ejector structure comprising: Ejector medium inlet, which is used to introduce the ejector medium; A Venturi channel, which extends from the ejector medium inlet and has an ejection port facing the first inlet; The inlet channel extends from the second inlet and connects to the Venturi channel, thereby introducing the second reactant from the second inlet into the Venturi channel as the inlet flows through it, and dispersing and mixing the second reactant with the first reactant as it is ejected from the nozzle toward the first reactant from the first inlet.

2. The microchannel reactor for exothermic reactions according to claim 1, characterized in that, A reserved liquid-holding cavity is configured between the injection port of the Venturi channel and the first inlet.

3. The microchannel reactor for exothermic reactions according to claim 1, characterized in that, The first inlet includes a plurality of micro-inlets, all facing the injection port of the Venturi channel, the plurality of micro-inlets being used to disperse the first reactant.

4. The microchannel reactor for exothermic reactions according to any one of claims 1 to 3, characterized in that, Two drainage channels extend from the first inlet; wherein: The two drainage channels are located on both sides of the Venturi channel and are laterally connected to the Venturi channel on both sides.

5. The microchannel reactor for exothermic reactions according to any one of claims 1 to 3, characterized in that, The ejector structure includes multiple ejector structures arranged in parallel. Both the first inlet and the second inlet include multiple inlets, and each ejector structure corresponds to one first inlet and one second inlet.

6. The microchannel reactor for exothermic reactions according to claim 1, characterized in that, The microchannel reactor for the exothermic reaction also has two heat exchange layers located on both sides of the reaction layer, and each heat exchange layer is configured with a heat exchange microchannel having a heat exchange medium inlet and a heat exchange medium outlet; the flow direction of the heat exchange medium in the heat exchange microchannel is opposite to the flow direction of the fluid in the reaction microchannel.

7. The microchannel reactor for exothermic reactions according to claim 6, characterized in that, The microchannel reactor for the exothermic reaction includes a sealing plate, a first substrate, a second substrate, and a third substrate stacked sequentially from front to back; the first substrate and the second substrate define the reaction layer, the sealing plate and the first substrate define the heat exchange layer located in front of the reaction layer, and the second substrate and the third substrate define the heat exchange layer located behind the reaction layer; wherein: The sealing plate and / or the third substrate are provided with at least: a first reactant supply interface connected to the first inlet for supplying the first reactant, a second reactant supply interface connected to the second inlet for supplying the second reactant, a product outlet interface connected to the product outlet for exporting the reaction product, and an ejector medium supply interface connected to the ejector medium inlet for supplying the ejector medium. A second reactant supply channel is constructed between the second reactant supply interface and the second inlet, and an ejector medium supply channel is constructed between the ejector medium supply interface and the ejector medium inlet. The main body of the second reactant supply channel and the main body of the ejector medium supply channel are not located on the same layer as the reaction layer.

8. The microchannel reactor for exothermic reactions according to claim 7, characterized in that, The second reactant supply channel is located in the same layer as the heat exchange layer on the rear side of the reaction layer, and the ejector medium supply channel is located in the same layer as the heat exchange layer on the front side of the reaction layer. or The ejector medium supply channel is located in the same layer as the heat exchange layer on the rear side of the reaction layer, and the second reactant supply channel is located in the same layer as the heat exchange layer on the front side of the reaction layer.

9. The microchannel reactor for exothermic reactions of claim 7, wherein, The sealing plate and / or the third substrate are further provided with: a heat exchange medium supply interface communicating with the heat exchange medium inlet for supplying heat exchange medium, and a heat exchange medium outlet interface communicating with the heat exchange medium outlet for discharging heat exchange medium; wherein: The first reactant supply interface, the second reactant supply interface, the ejector medium supply interface, the product outlet interface, the heat exchange medium supply interface, and the heat exchange medium outlet interface are arranged in the area of ​​the sealing plate near the same side.

10. The microchannel reactor for exothermic reactions of claim 1, wherein, The reaction microchannels are used for nitration reactions.

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