CSTR (continuous stirred-tank reactor) with gas circulation reflux water diversion function
Through the CSTR reactor with gas reflux water separation, nitrogen flow circulation and multi-stage reaction device are used to solve the problem of low water separation efficiency in continuous process in chemical production, and an efficient water separation process is achieved, which improves the reaction conversion rate and reduces the occurrence of side reactions.
Patent Information
- Application Number
- CN202421714876.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-19
- Publication Date
- 2025-07-04
- Estimated Expiration
- 2034-07-19
AI Technical Summary
In chemical production, how to achieve an effective water separation process in a short time in the continuous process, reduce the heating time of materials, reduce the reaction temperature, improve conversion and selectivity, especially when the water generation amount reaches equilibrium, the reflux water separation efficiency is reduced.
The CSTR reactor with gas recirculation and reflux water separation is adopted to accelerate the water separation process through the circulation of nitrogen streams, and the series connection of multiple reaction devices and liquid sealing pipes are connected to achieve staging dehydration. The gas flow and stirring reactants are evenly distributed through the design of the air pipe and the stirring paddle, and uniform heating is carried out using a heating sleeve.
The continuous reflux water separation is achieved, the water separation speed is improved, the reaction temperature is reduced, the reaction conversion rate and selectivity is improved, and the occurrence of side reactions is reduced.
Smart Images
Figure CN223055628U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of chemical production process equipment, in particular to a CSTR reactor with gas circulation reflux water separation. Background Technique
[0002] Among many types of chemical reactions, there is a class of equilibrium reactions with water generation during the reaction process. When the water generation reaches a certain concentration, the reaction reaches equilibrium, and the ratio of raw materials to products no longer changes positively with the extension of the reaction time. In order to make the reaction continue, it is necessary to use a solvent that forms an azeotrope with water. By means of reflux water separation, the water content in the reaction system is reduced, so that the equilibrium shifts to the right to achieve a high reaction conversion rate; however, during the reflux water separation process, the water content is a decreasing process. When the water content is low, the reflux water separation efficiency decreases accordingly, and the less water is carried away by the evaporation of a unit weight of azeotropic solvent. Sometimes, long-term heating reflux significantly increases the degree of side reactions. For this situation, it is necessary to seek a method to reduce the reflux water separation time or lower the reflux temperature, and a method to reduce side reactions on the premise of ensuring the reaction conversion rate;
[0003] In chemical production, continuous processes are used more and more in production practice, but it is very difficult to realize the application scenarios of such reflux water separation; the liquid holdup and reaction residence time in the continuous process are significantly reduced compared with the batch process. How to achieve effective water separation in a short time, accelerate the water separation process, reduce the heating time of the material, and lower the reaction temperature are the problems to be solved in the continuous process to improve the conversion rate and selectivity. Content of the Utility Model
[0004] The purpose of the utility model is to provide a CSTR reactor with gas circulation reflux water separation, to realize the continuity of reflux water separation, and to accelerate the water separation process through the circulation of nitrogen gas flow, so as to improve the reaction speed.
[0005] To achieve the above purpose, the utility model provides the following technical solution: a CSTR reactor with gas circulation reflux water separation, including at least two sets of reaction devices. The reaction device includes a reaction kettle, a gas distribution pipe, a gas compression pump, a water separator, a condenser, and a breathing valve; a kettle cover is arranged on the reaction kettle, and an exhaust pipe and a nitrogen pipe are arranged on the kettle cover; the gas distribution ring is arranged at the bottom inside the reaction kettle, the outlet end of the gas compression pump is communicated with the gas distribution pipe through a pipeline, the exhaust pipe is communicated with the water separator inlet through a pipeline, the outlet of the water separator is communicated with the condenser inlet, the outlet of the condenser is communicated with the gas compression pump inlet through a three-way pipe, and the breathing valve is arranged at the other end of the three-way pipe.
[0006] In order to evenly distribute the air flow, as a preferred embodiment of the CSTR reactor with gas circulation, reflux and water separation of the present utility model, the air distribution pipe is in a ring structure, and a distribution pipe with a cross structure is arranged inside the air distribution pipe, and air distribution through holes are opened on the air distribution pipe and the distribution pipe.
[0007] In order to pump the reactants in the previous-stage reaction kettle into the next-stage reaction kettle for reaction, as a preferred embodiment of the CSTR reactor with gas circulation, reflux and water separation of the present utility model, two adjacent reaction kettles are connected through a pipe with a liquid seal.
[0008] In order to facilitate stirring of the reaction, as a preferred embodiment of the CSTR reactor with gas circulation, reflux and water separation of the present utility model, a stirring paddle is arranged inside the reaction kettle, a motor is arranged on the reaction kettle, and the output end of the motor is fixedly connected to the upper end of the stirring paddle through a rotating shaft.
[0009] In order to facilitate heating of the reaction kettle, as a preferred embodiment of the CSTR reactor with gas circulation, reflux and water separation of the present utility model, a heating jacket is arranged on the outer wall of the reaction kettle.
[0010] Compared with the prior art, the beneficial effects of the present utility model are as follows:
[0011] The present utility model connects multiple reaction devices in series and dehydrates them step by step according to the reaction process. In the previous stage, due to the high water content in the reaction liquid, the water separation efficiency is high, and the working frequency of the compressor can be appropriately reduced. In the later stage of the reaction, which is close to the reaction end point and has a low water content, the gas circulation volume can be increased and the air flow speed can be increased to evaporate more solvents and carry out water, accelerating the evaporation of water, so as to achieve the purpose of accelerating the reaction. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 is a schematic structural diagram of the present utility model;
[0013] Figure 2 is a top view structural diagram of the air distribution pipe and the distribution pipe of the present utility model.
[0014] In the figure: 1, reaction kettle; 2, air distribution pipe; 3, gas compression pump; 4, water separator; 5, condenser; 6, breathing valve; 7, kettle cover; 8, exhaust pipe; 9, nitrogen pipe; 10, three-way pipe; 11, distribution pipe; 12, air distribution through hole; 13, liquid seal; 14, stirring paddle; 15, motor; 16, heating jacket. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0015] Please refer to Figures 1 to 2, A CSTR reactor with gas circulation and reflux water separation, comprising at least two sets of reaction devices. The reaction devices include a reaction kettle 1, a gas distribution pipe 2, a gas compression pump 3, a water separator 4, a condenser 5, and a breathing valve 6. A kettle cover 7 is provided on the reaction kettle 1, and an exhaust pipe 8 and a nitrogen pipe 9 are provided on the kettle cover 7. The gas distribution ring is arranged at the bottom inside the reaction kettle 1. The outlet end of the gas compression pump 3 is connected to the gas distribution pipe 2 through a pipeline. The exhaust pipe 8 is connected to the inlet of the water separator 4 through a pipeline. The outlet of the water separator 4 is connected to the inlet of the condenser 5. The outlet of the condenser 5 is connected to the inlet of the gas compression pump 3 through a three-way pipe 10. The breathing valve 6 is arranged at the other end of the three-way pipe 10. Adjacent two reaction kettles 1 are connected through a pipeline with a liquid seal.
[0016] In this embodiment: During the reaction, nitrogen is filled into the reaction kettle 1 through the nitrogen pipe 9 for protection (nitrogen protection is to avoid oxygen interference), and a small air flow is maintained inside the reaction kettle 1. The excess gas is discharged from the breathing valve 6. The gas compression pump 3 compresses the gas at the end of the condenser 5, and the compressed gas is distributed into the reaction kettle 1 below the reaction liquid level through the gas distribution pipe 2. Under the action of stirring, the air flow carries the hot solvent to evaporate rapidly and enters the gas phase space (above the reaction liquid). During the evaporation process, the water in the solution evaporates rapidly along with the evaporation of the solvent. The mixed gas in the gas phase space (the gas contains nitrogen, solvent vapor, and water vapor). With the circulation of the air flow, nitrogen, solvent vapor, and water vapor quickly enter the condenser 5 through the water separator 4. The condenser 5 fully condenses the solvent and water and returns them to the water separator 4. Nitrogen is then compressed back into the reaction kettle 1 again. The condensate in the water separator 4 is divided into an aqueous phase and an organic phase. The organic phase returns to the reaction kettle 1 to continue participating in the reaction. Due to the participation of nitrogen circulation, the water separation speed is greatly increased, and the reaction temperature is significantly reduced.
[0017] Adjacent two reaction kettles 1 are connected through a pipeline with a liquid seal, so that multiple reaction devices are connected in series, and dehydration is carried out in stages according to the reaction process. In the previous stage, due to the high water content in the reaction liquid, the water separation efficiency is high, and the working frequency of the compressor can be appropriately reduced. In the latter stage, the reaction is close to the reaction end point, the water content is low, and the gas circulation amount can be increased, the air flow speed can be increased, so that more solvent evaporates to carry out water, and the water evaporation is accelerated, so as to achieve the purpose of accelerating the reaction.
[0018] As a technical optimization scheme of the present utility model, the gas distribution pipe 2 is in a ring structure, and a distribution pipe 11 with a cross structure is arranged inside the gas distribution pipe 2. Gas distribution through holes 12 are opened on the gas distribution pipe 2 and the distribution pipe 11.
[0019] In this embodiment: The gas distribution pipe 2 and the distribution pipe 11 increase the coverage area and are easy to evenly distribute the air flow.
[0020] As a technical optimization scheme of the present utility model, adjacent two reaction kettles 1 are connected through a pipeline 13 with a liquid seal.
[0021] In this embodiment: Through the liquid seal 13, the reactants in the previous-stage reaction kettle 1 can flow by gravity into the subsequent-stage reaction kettle 1 for reaction, and the cross-flow of gases with different moisture contents between the two kettles can be isolated, realizing the continuity of reflux water separation.
[0022] As a technical optimization scheme of the present utility model, a stirring paddle 14 is arranged inside the reaction kettle 1, and a motor 15 is arranged on the reaction kettle 1. The output end of the motor 15 is fixedly connected to the upper end of the stirring paddle 14 through a rotating shaft.
[0023] In this embodiment: When the motor 15 is started, the stirring paddle 14 rotates inside the reaction kettle 1, which is easy to stir the inside of the reaction kettle 1 and easy to make the reaction inside the reaction kettle 1 uniform.
[0024] As a technical optimization scheme of the present utility model, a heating jacket 16 is arranged on the outer wall of the reaction kettle 1.
[0025] In this embodiment: The heating jacket 16 is an oil bath heating jacket. By adding heat-conducting oil or water into the jacket as a heating medium, the liquid in the jacket is heated by heating the external oil bath, realizing the heating reaction of the reaction kettle 1. This heating method is uniform and not easy to cause local overheating, resulting in the decomposition of materials.
[0026] Working principle: When the reaction proceeds, nitrogen gas is filled into the reaction kettle 1 through the nitrogen gas pipe 9 for protection, and a small air flow is maintained inside the reaction kettle 1. The excess gas is discharged from the breathing valve 6. The gas compression pump 3 compresses the gas at the tail end of the condenser 5, and the compressed gas is distributed into the reaction kettle 1 below the reaction liquid level through the air distribution pipe 2. Under the action of stirring, the air flow carries the hot solvent to evaporate rapidly and enters the gas phase space. During the evaporation process, the water in the solution evaporates rapidly along with the evaporation of the solvent. The mixed gas in the gas phase space, along with the circulation of the air flow, the nitrogen gas, solvent vapor and water vapor quickly pass through the water separator 4 and enter the condenser 5. The condenser 5 fully condenses the solvent and water and returns them to the water separator 4, and the nitrogen gas is compressed again and returned to the reaction kettle 1; the condensate in the water separator 4 is divided into an aqueous phase and an organic phase, and the organic phase returns to the reaction kettle 1 to continue participating in the reaction; due to the participation of the nitrogen gas cycle, the reflux water separation speed is greatly increased and the reaction temperature is significantly reduced; adjacent two reaction kettles 1 are connected through a pipeline with a liquid seal, so that multiple reaction devices are connected in series, and dehydration is carried out in stages according to the reaction process. Since the water content in the reaction liquid of the previous stage is high and the water separation efficiency is high, the working frequency of the compressor can be appropriately reduced. The reaction in the subsequent stage is close to the reaction end point, the water content is low, the gas circulation amount can be increased, the air flow speed can be increased, so that more solvent evaporates to carry out water, accelerating the evaporation of water, and thus achieving the purpose of accelerating the reaction.
[0027] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.
Claims
1. A CSTR reactor with gas circulation reflux water separation, characterized in that: It includes at least two sets of reaction devices. The reaction devices include a reaction kettle (1), a gas distribution pipe (2), a gas compression pump (3), a water separator (4), a condenser (5), and a breather valve (6); a kettle cover (7) is provided on the reaction kettle (1), and an exhaust pipe (8) and a nitrogen pipe (9) are provided on the kettle cover (7); the gas distribution ring is arranged at the bottom inside the reaction kettle (1), the outlet end of the gas compression pump (3) is communicated with the gas distribution pipe (2) through a pipeline, the exhaust pipe (8) is communicated with the inlet of the water separator (4) through a pipeline, the outlet of the water separator (4) is communicated with the inlet of the condenser (5), the outlet of the condenser (5) is communicated with the inlet of the gas compression pump (3) through a three-way pipe (10), and the breather valve (6) is arranged at the other end of the three-way pipe (10); adjacent two reaction kettles (1) are communicated through a pipeline with a liquid seal.
2. The CSTR reactor with gas circulation reflux water separation according to claim 1, wherein: The gas distribution pipe (2) is of an annular structure, and a distribution pipe (11) with a cross structure is arranged inside the gas distribution pipe (2), and gas distribution through holes (12) are formed on the gas distribution pipe (2) and the distribution pipe (11).
3. A CSTR reactor with gas circulation reflux water separation according to claim 1, characterized in that: Adjacent two reaction kettles (1) are communicated through a pipeline with a liquid seal (13).
4. A CSTR reactor with gas circulation reflux water separation according to claim 1, characterized in that: A stirring paddle (14) is arranged inside the reaction kettle (1), a motor (15) is arranged on the reaction kettle (1), and the output end of the motor (15) is fixedly connected with the upper end of the stirring paddle (14) through a rotating shaft.
5. A CSTR reactor with gas circulation reflux water separation according to claim 1, characterized in that: A heating jacket (16) is arranged on the outer wall of the reaction kettle (1).