Loop reactor

Abstract

The utility model relates to the technical field of chemical reaction equipment, and provides a loop reactor, which is characterized in that a discharge pipe and an injection pipe are arranged at the bottom of a kettle body at an interval, so that a gas-liquid phase injected into the injection pipe flows towards the top of the kettle body. When the gas-liquid phase flows to the top of the kettle body, the gas-liquid phase turns back to flow towards the bottom of the kettle body under the obstruction of the top of the kettle body. Therefore, the sprayed gas-liquid phase flows back and forth in the kettle body, the gas-liquid phase mixing path is prolonged, and the sprayed gas-liquid phase is prevented from being directly discharged from the discharge pipe. Due to the fact that the turbulent flow assembly is arranged at one end of the injection pipe, injected gas and liquid phases are intensively mixed under the action of the turbulent flow assembly, and it is guaranteed that the gas and liquid phases are fully mixed and react in the kettle body. By means of the design, the mixing path is prolonged, the mixing strength is enhanced, it is guaranteed that the gas phase and the liquid phase are fully mixed and reacted, and the conversion efficiency is further improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical reaction equipment, in particular to a loop reactor. Background Art

[0002] A loop reactor is mainly composed of a reactor (pressurized or normal pressure), a circulation pump, a heat exchanger and a venturi ejector. The gas phase is introduced by the vacuum formed by the high-speed flow of the liquid, and the mixing box is sprayed into the reactor to form a circulation flow for reaction. It is suitable for reactions with slow rates and heterogeneous raw materials, such as gas-liquid heterogeneous reactions and liquid-liquid heterogeneous reactions with fine particle catalysts.

[0003] In the existing document (application number 202122462900.6), a loop reactor with a high-efficiency Venturi injector is disclosed. The Venturi injector is arranged at one end of the high-pressure reactor. When the liquid and gas ejected from the nozzle of the Venturi injector enter the injection tube and the mixing reaction tube, the gas and liquid phases are intensely mixed in the injection tube and the mixing reaction tube, forming a good reaction effect and improving the conversion efficiency.

[0004] However, the above scheme adopts a Venturi ejector, which can enhance the mixing of gas-liquid two-phases to a certain extent. However, it is limited by the structural design of the loop reactor, causing the injected gas-liquid mixed phase to quickly flow out of the high-pressure reactor in the direction of injection, resulting in the gas-liquid phase being unable to fully mix and react, which in turn leads to certain limitations in improving the gas-liquid conversion efficiency. Utility Model Content

[0005] Based on the above background, the purpose of the utility model is to provide a loop reactor to ensure sufficient mixing reaction of gas and liquid phases and further improve the conversion efficiency.

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

[0007] A loop reactor comprises: a reaction kettle, comprising a kettle body, an injection pipe, a spoiler assembly and a discharge pipe, wherein the discharge pipe and the injection pipe are arranged at the bottom of the kettle body at intervals, one end of the injection pipe extends into the interior of the kettle body and faces the top of the kettle body, the spoiler assembly is located in the kettle body and between one end of the injection pipe and the top of the kettle body, the injection pipe has an air inlet pipe and a reflux pipe at one end outside the kettle body, and the spoiler assembly is used to stir the gas-liquid phase sprayed from the injection pipe; a circulating pump connected to the discharge pipe; a heat exchanger for receiving the gas-liquid phase output by the circulating pump and performing heat exchange on the gas-liquid phase; a separation mechanism for receiving the gas-liquid phase output by the heat exchanger, separating the reaction products, and transporting the remaining gas-liquid phase to the reflux pipe.

[0008] Furthermore, the spoiler assembly includes a mounting bracket, a rotating shaft and a plurality of blades, the mounting bracket is fixed on the inner wall of the kettle body, the rotating shaft is rotatably disposed on the mounting bracket, the blades are distributed at intervals around the axis of the rotating shaft, and the axial direction of the rotating shaft is consistent with the length direction of the injection pipe.

[0009] Furthermore, an annular groove is provided on the inner wall of the kettle body, and the mounting bracket is fixed in the annular groove.

[0010] Furthermore, the mounting bracket includes a mounting ring and a first sealing plate and a second sealing plate arranged at the upper and lower ends of the mounting ring, the rotating shaft can be rotatably located between the first sealing plate and the second sealing plate, and the plate surfaces of the first sealing plate and the second sealing plate are both penetrated by a hollow portion.

[0011] Furthermore, the inner wall of the reactor comprises a drainage surface, the drainage surface is located on the side of the spoiler assembly facing away from the injection pipe, the drainage surface is a conical surface, and the cross-sectional area of ​​the drainage surface increases as it is closer to the spoiler assembly.

[0012] Furthermore, the injection pipe includes a diversion section and a flow expansion section which are interconnected. The diversion section is arranged at the bottom of the kettle body and partially extends into the kettle body. The flow expansion section is located in the kettle body. The end of the flow expansion section away from the diversion section has a plurality of injection holes, and each of the injection holes is arranged toward the spoiler assembly.

[0013] Furthermore, the cross-sectional area of ​​the flow expansion section gradually increases from one end of the flow expansion section close to the flow diversion section to one end of the flow expansion section far from the flow diversion section.

[0014] Furthermore, the loop reactor further comprises a mixer, and the mixer is connected between the circulation pump and the heat exchanger.

[0015] Furthermore, the mixer has parallel and spaced mixing chambers and guide channels, a flow-blocking protrusion is provided in the middle of the mixing chamber, and the guide channel is S-shaped, one end of which is connected to the mixing chamber and the other end is connected to the heat exchanger.

[0016] The utility model has the following beneficial effects:

[0017] (1) The discharge pipe and the injection pipe are spaced apart at the bottom of the kettle body so that the gas-liquid phase injected into the injection pipe flows toward the top of the kettle body. When the gas-liquid phase flows to the top of the kettle body, it turns back and flows toward the bottom of the kettle body due to the obstruction of the top of the kettle body. This allows the injected gas-liquid phase to flow back and forth inside the kettle body, which is beneficial to extend the gas-liquid mixing path and prevent the injected gas-liquid phase from being directly discharged from the discharge pipe. Since a spoiler component is provided at one end of the injection pipe, the injected gas-liquid phase is enhanced in mixing under the action of the spoiler component, ensuring that the gas-liquid phase is fully mixed and reacted in the kettle body. This design not only extends the mixing path, but also enhances the mixing force, ensuring that the gas-liquid phase is fully mixed and reacted, thereby further improving the conversion efficiency.

[0018] (2) The turbulent component is designed as a rotating shaft and a paddle, so that the injected gas and liquid phase can drive the paddle to rotate around the axis of the rotating shaft; the rotating paddle can also stir the injected gas and liquid phase. In this way, the gas and liquid phases are automatically stirred without introducing additional power, thereby enhancing gas-liquid mixing.

[0019] (3) A drainage surface is provided on the side of the spoiler assembly facing away from the injection pipe, and the drainage surface is designed to be a conical surface, so that the gas and liquid phases reaching the drainage surface can flow along the conical surface toward the periphery of the injection pipe, ensuring uniform distribution of the gas and liquid phases.

[0020] (4) A mixer is provided between the heat exchanger and the circulation pump so that the extracted gas and liquid phase first enter the mixing chamber and then the S-shaped flow guide channel. Since there is a flow-blocking protrusion in the mixing chamber, the gas and liquid phase flowing into the mixing chamber will change its flow path under the flow blocking of the flow-blocking protrusion, so that the gas and liquid phase will reflux around the flow-blocking protrusion, thereby strengthening the mixing of the gas and liquid phases and improving the mixing effect, thereby further improving the conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0022] Figure 1 is a schematic structural diagram of a loop reactor described in one embodiment;

[0023] Figure 2 It is a structural schematic diagram of a reaction kettle described in an embodiment;

[0024] Figure 3 is a structural cross-sectional view of a reaction kettle described in an embodiment;

[0025] Figure 4 It is a structural cross-sectional view of a kettle body described in one embodiment;

[0026] Figure 5 Schematic diagram of the structure of a spoiler assembly described in one embodiment.

[0027] Description of Figure Numbers:

[0028] 100 is a loop reactor; 10 is a reactor; 11 is a reactor body; 111 is an annular groove; 112 is a drainage surface; 12 is an injection pipe; 121 is a drainage section; 122 is a flow expansion section; 123 is an injection hole; 124 is an air inlet pipe; 125 is a reflux pipe; 126 is a connecting pipe; 127 is a liquid inlet pipe; 13 is a discharge pipe; 14 is a spoiler assembly; 141 is a mounting bracket; 142 is a rotating shaft; 143 is a blade; 144 is a mounting ring; 145 is a first sealing plate; 146 is a second sealing plate; 147 is a hollow portion; 148 is an axis; 20 is a circulating pump; 30 is a heat exchanger; 40 is a separation mechanism; 41 is a discharge port; 50 is a mixer; 51 is a mixing chamber; 52 is a flow-blocking protrusion; and 53 is a diversion channel.

[0029] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] In addition, in the present utility model, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. 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 utility model.

[0033] In one embodiment, please refer to Figures 1 to 5 The present application provides a loop reactor 100, comprising: a reactor 10, comprising a reactor body 11, an injection pipe 12, a spoiler assembly 14 and a discharge pipe 13, wherein the discharge pipe 13 and the injection pipe 12 are arranged at the bottom of the reactor body 11 at intervals, one end of the injection pipe 12 extends into the interior of the reactor body 11 and faces the top of the reactor body 11, the spoiler assembly 14 is located in the reactor body 11 and is located between one end of the injection pipe 12 and the top of the reactor body 11, the injection pipe 12 has an air inlet pipe 124 and a reflux pipe 125 at one end outside the reactor body 11, and the spoiler assembly 14 is used to stir the gas-liquid phase sprayed from the injection pipe 12; a circulating pump 20, which is connected to the discharge pipe 13; a heat exchanger 30, which is used to receive the gas-liquid phase output by the circulating pump 20 and perform heat exchange on the gas-liquid phase; a separation mechanism 40, which is used to receive the gas-liquid phase output by the heat exchanger 30, separate the reaction product, and transport the remaining gas-liquid phase to the reflux pipe 125.

[0034] In the above-mentioned loop reactor 100, the discharge pipe 13 and the injection pipe 12 are arranged at a distance at the bottom of the kettle body 11, so that the gas-liquid phase injected into the injection pipe 12 flows toward the top of the kettle body 11. When the gas-liquid phase flows to the top of the kettle body 11, it turns back and flows toward the bottom of the kettle body 11 under the obstruction of the top of the kettle body 11. In this way, the injected gas-liquid phase flows back and forth inside the kettle body 11, which is conducive to extending the gas-liquid phase mixing path and avoiding the injected gas-liquid phase from being directly discharged from the discharge pipe 13. Since a spoiler component 14 is provided at one end of the injection pipe 12, the injected gas-liquid phase is enhanced in mixing under the action of the spoiler component 14, ensuring that the gas-liquid phase is fully mixed and reacted in the kettle body 11. Such a design not only extends the mixing path, but also strengthens the mixing force, ensuring that the gas-liquid phase is fully mixed and reacted, thereby further improving the conversion efficiency.

[0035] It should be explained that the gas and liquid phases flowing out of the discharge pipe 13 will flow through the heat exchanger 30 and the separation mechanism 40 in sequence under the action of the circulation pump 20. The gas and liquid phases after passing through the separation mechanism 40 will flow back to the kettle body 11 from the reflux pipe 125 to carry out a circulation reaction. Among them, the heat exchanger 30 refers to a device that can exchange heat between the gas and liquid phases in the flow process, which can be a tubular heat exchange device.

[0036] The separation mechanism 40 refers to a device that can separate the reaction product from the gas-liquid phase and reflux the excess gas-liquid phase to the reflux pipe 125. For example, the separation mechanism 40 has a discharge port 41 for outputting the reaction product, and the separation mechanism 40 is connected to the reflux pipe 125 through a connecting pipe 126. At the same time, the connecting pipe 126 has a liquid inlet pipe 127. Taking the conversion of nitro compounds into amino compounds as an example, the nitro compound and hydrogen are respectively sprayed into the injection pipe 12 through the air inlet pipe 124 and the liquid inlet pipe 127; and then sprayed into the kettle body 11 through the injection pipe 12 to perform a mixed reaction under the action of a catalyst. Since the structure of the separation mechanism 40 is not the object to be improved in this embodiment, the structure of the separation mechanism 40 can directly refer to the existing structure and existing literature, and will not be described in detail here.

[0037] For further information, please refer to Figure 3 and Figure 5 The spoiler assembly 14 includes a mounting bracket 141, a rotating shaft 142 and a plurality of paddles 143. The mounting bracket 141 is fixed on the inner wall of the kettle body 11. The rotating shaft 142 is rotatably arranged on the mounting bracket 141. The paddles 143 are spaced around the axis 148 of the rotating shaft 142. The direction of the axis 148 of the rotating shaft 142 is consistent with the length direction of the injection pipe 12. In this way, the spoiler assembly 14 is designed as a rotating shaft 142 and paddles 143, so that the injected gas-liquid phase can drive the paddles 143 to rotate around the axis 148 of the rotating shaft 142; the rotating paddles 143 can also stir the injected gas-liquid phase. In this way, the automatic stirring of the gas-liquid phase is achieved without introducing additional power, and the gas-liquid mixing is enhanced.

[0038] It should be explained that the axis 148 of the rotating shaft 142 is consistent with the length direction of the injection pipe 12, so that the injected gas and liquid phase can better act on the blade 143 to drive the blade 143 to rotate.

[0039] For further information, please refer to Figure 4 and Figure 5 The inner wall of the kettle body 11 is provided with an annular groove 111, and the mounting bracket 141 is fixed in the annular groove 111. In this way, it is ensured that the spoiler assembly 14 is stably installed in the kettle body 11, so as to stably disturb the gas-liquid phase.

[0040] In one embodiment, the mounting bracket 141 includes a mounting ring 144 and a first sealing plate 145 and a second sealing plate 146 disposed at the upper and lower ends of the mounting ring 144. The rotating shaft 142 can be rotatably located between the first sealing plate 145 and the second sealing plate 146. The plate surfaces of the first sealing plate 145 and the second sealing plate 146 are penetrated with a hollow portion 147. It can be seen that the ejected gas and liquid phase enters from the hollow portion 147 to between the first sealing plate 145 and the second sealing plate 146, thereby blowing the blade 143 to make it rotate stably.

[0041] There are many ways to connect the first sealing plate 145 and the second sealing plate 146 to the mounting ring 144, such as bolt connection, clamping, welding, bonding, etc.

[0042] In one embodiment, please refer to Figure 3 The inner wall of the reactor 10 includes a drainage surface 112, which is located on the side of the spoiler assembly 14 facing away from the injection pipe 12, and is a conical surface. The cross-sectional area of ​​the drainage surface 112 is larger as it is closer to the spoiler assembly 14. It can be seen that the drainage surface 112 is arranged on the side of the spoiler assembly 14 facing away from the injection pipe 12, and the drainage surface 112 is designed as a conical surface, so that the gas and liquid phases reaching the drainage surface 112 can flow along the conical surface toward the periphery of the injection pipe 12, ensuring uniform distribution of the gas and liquid phases.

[0043] To facilitate understanding of the cross section of the drainage surface 112, please refer to Figure 4 , the cross section of the drainage surface 112 is Figure 4 The section indicated by A1.

[0044] In one embodiment, please refer to Figure 4 The injection pipe 12 includes a drainage section 121 and a diffusion section 122 which are interconnected. The drainage section 121 is arranged at the bottom of the kettle body 11 and partially extends into the kettle body 11. The diffusion section 122 is located in the kettle body 11. The diffusion section 122 has a plurality of injection holes 123 at one end away from the drainage section 121, and each injection hole 123 is arranged toward the spoiler assembly 14.

[0045] For further information, please refer to Figure 4 The cross-sectional area of ​​the expansion section 122 gradually increases from the end of the expansion section 122 close to the drainage section 121 to the end of the expansion section 122 far from the drainage section 121. It can be seen that this is beneficial to expand the distribution range of the gas-liquid phase and improve the distribution uniformity of the gas-liquid phase in the kettle body 11.

[0046] To facilitate understanding of the cross section of the expansion section 122, please refer to Figure 4 , the cross section of the expansion section 122 is Figure 4 The section represented by A2.

[0047] In one embodiment, please refer to Figure 1 The loop reactor 100 further includes a mixer 50 , which is connected between the circulation pump 20 and the heat exchanger 30 .

[0048] For further information, please refer to Figure 1The mixer 50 has a mixing chamber 51 and a flow guide channel 53 arranged in parallel and spaced apart. A flow blocking protrusion 52 is provided in the middle of the mixing chamber 51. The flow guide channel 53 is designed in an S shape, one end of which is connected to the mixing chamber 51, and the other end is connected to the heat exchanger 30. It can be seen that the mixer 50 is arranged between the heat exchanger 30 and the circulating pump 20, so that the extracted gas and liquid phase first enter the mixing chamber 51, and then enter the S-shaped flow guide channel 53. Since the mixing chamber 51 has a flow blocking protrusion 52, the gas and liquid phase flowing into the mixing chamber 51 will change its flow path under the flow blocking of the flow blocking protrusion 52, so that the gas and liquid phase will reflux around the flow blocking protrusion 52, strengthen the mixing of the gas and liquid phases, improve the mixing effect, and further improve the conversion efficiency.

[0049] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A loop reactor, characterized in that: include: A reaction kettle (10) comprises a kettle body (11), an injection pipe (12), a spoiler assembly (14) and a discharge pipe (13); the discharge pipe (13) and the injection pipe (12) are arranged at the bottom of the kettle body (11) at a distance; one end of the injection pipe (12) extends into the kettle body (11) and faces the top of the kettle body (11); the spoiler assembly (14) is located in the kettle body (11) and between one end of the injection pipe (12) and the top of the kettle body (11); the end of the injection pipe (12) located outside the kettle body (11) has an air inlet pipe (124) and a reflux pipe (125); the spoiler assembly (14) is used to stir the gas-liquid phase sprayed from the injection pipe (12); a circulation pump (20) connected to the discharge pipe (13); a heat exchanger (30) for receiving the gas-liquid phase output by the circulation pump (20) and performing heat exchange on the gas-liquid phase; The separation mechanism (40) is used to receive the gas and liquid phases output by the heat exchanger (30), separate the reaction products, and transport the remaining gas and liquid phases to the reflux pipe (125).

2. The loop reactor according to claim 1, characterized in that The spoiler assembly (14) comprises a mounting bracket (141), a rotating shaft (142) and a plurality of paddles (143); the mounting bracket (141) is fixed on the inner wall of the kettle body (11); the rotating shaft (142) is rotatably arranged on the mounting bracket (141); the paddles (143) are distributed at intervals around the axis (148) of the rotating shaft (142); and the direction of the axis (148) of the rotating shaft (142) is consistent with the length direction of the injection pipe (12).

3. The loop reactor according to claim 2, characterized in that An annular groove (111) is provided on the inner wall of the kettle body (11), and the mounting bracket (141) is fixed in the annular groove (111).

4. The loop reactor according to claim 2, characterized in that The mounting bracket (141) comprises a mounting ring (144) and a first sealing plate (145) and a second sealing plate (146) arranged at the upper and lower ends of the mounting ring (144); the rotating shaft (142) can be rotatably located between the first sealing plate (145) and the second sealing plate (146); and the plate surfaces of the first sealing plate (145) and the second sealing plate (146) are both penetrated by a hollow portion (147).

5. The loop reactor according to claim 1, characterized in that The inner wall of the reaction kettle (10) comprises a drainage surface (112), the drainage surface (112) being located on a side of the spoiler component (14) facing away from the injection pipe (12), the drainage surface (112) being a conical surface, and the cross-sectional area of ​​the drainage surface (112) is larger the closer it is to the spoiler component (14).

6. The loop reactor according to claim 1, characterized in that The injection pipe (12) comprises a flow guide section (121) and a flow expansion section (122) which are interconnected. The flow guide section (121) is arranged at the bottom of the kettle body (11) and partially extends into the kettle body (11). The flow expansion section (122) is located in the kettle body (11). An end of the flow expansion section (122) away from the flow guide section (121) has a plurality of injection holes (123). Each of the injection holes (123) is arranged toward the spoiler assembly (14).

7. The loop reactor according to claim 6, characterized in that The cross-sectional area of ​​the expansion section (122) gradually increases from one end of the expansion section (122) close to the diversion section (121) to one end of the expansion section (122) far from the diversion section (121).

8. The loop reactor according to any one of claims 1 to 7, characterized in that The loop reactor further comprises a mixer (50), wherein the mixer (50) is connected between the circulation pump (20) and the heat exchanger (30).

9. The loop reactor according to claim 8, characterized in that The mixer (50) has a mixing chamber (51) and a flow guide channel (53) arranged in parallel and at intervals. A flow blocking protrusion (52) is provided in the middle of the mixing chamber (51). The flow guide channel (53) is designed in an S shape, one end of which is connected to the mixing chamber (51) and the other end of which is connected to the heat exchanger (30).

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