CN110090602B

CN110090602B - Hydrogenation reaction system

Info

Publication number: CN110090602B
Application number: CN201910449664.9A
Authority: CN
Inventors: 王栋拣; 曾凡刚; 王平; 孙天山; 徐�明
Original assignee: Shenhua Engineering Technology Co ltd; China Shenhua Coal to Liquid Chemical Co Ltd
Current assignee: Shenhua Engineering Technology Co ltd; China Shenhua Coal to Liquid Chemical Co Ltd
Priority date: 2019-05-28
Filing date: 2019-05-28
Publication date: 2022-06-21
Anticipated expiration: 2039-05-28
Also published as: CN110090602A

Abstract

The invention relates to the technical field of fine chemical production and discloses a hydrogenation reaction system. The hydrogenation reaction system comprises: the device comprises a hydrogenation kettle (1), wherein a kettle body of the hydrogenation kettle is respectively connected with a feeding pipe (21), a hydrogenation pipe (22), a vacuum pipe (23), a nitrogen pipe (30) and a product discharge pipe (29), the outer wall of the hydrogenation kettle is provided with a hydrogenation kettle jacket (3), and a stirrer (2) is arranged inside the hydrogenation kettle; the cooling unit comprises a cooling pipeline arranged inside the hydrogenation kettle and a condenser (10) arranged outside the hydrogenation kettle, and the inlet and the outlet of the cooling pipeline are respectively communicated with the outlet and the inlet of the condenser. The hydrogenation reaction system provided by the invention has the advantages of fast heat transfer, stable temperature control, more uniform mixing of hydrogen and materials, improvement of product conversion rate and purity, prolongation of the service life of the noble metal catalyst, reduction of the loss of the noble metal catalyst, reduction of the labor intensity of workers, reduction of energy consumption, higher automation degree and high system safety.

Description

Hydrogenation reaction system

Technical Field

The invention relates to the technical field of fine chemical production, in particular to a hydrogenation reaction system for producing intermediates such as 3, 4-dichloroaniline and the like used for pesticides, dyes, medicines and the like.

Background

In the field of fine chemicals such as agricultural chemicals, dyes and medicines, it is necessary to obtain a reduced product by hydrogenation, and for example, 3, 4-dichloroaniline is a product obtained by reacting 3, 4-dichloronitrobenzene with hydrogen gas, and is mainly used in the agricultural chemical industry for synthesizing herbicides such as diuron, in the dye industry for synthesizing azo dyes, and in the medicine for synthesizing bactericides.

At present, the synthesis reaction of 3, 4-dichloroaniline is completed in a hydrogenation kettle, and the reaction process is as follows: conveying the 3, 4-dichloronitrobenzene to a head tank for metering, then putting the head tank into a hydrogenation kettle, starting stirring, manually adding a noble metal catalyst, replacing air in the hydrogenation kettle with nitrogen, introducing steam into a jacket of the hydrogenation kettle after replacement is finished, and closing the steam when materials in the kettle reach 90 ℃. And then, introducing hydrogen from a hydrogen inlet at the bottom of the hydrogenation kettle to carry out hydrogenation reaction. In the process of introducing hydrogen, the adding amount of hydrogen is controlled, and cooling water is injected into the jacket of the hydrogenation kettle to reduce the temperature so as to control the reaction temperature. And after the reaction is finished, discharging from a discharge port at the bottom of the hydrogenation kettle, conveying to a filtering system, filtering the hydrogenation liquid, taking out the noble metal catalyst, feeding into the hydrogenation kettle for recycling, and conveying the product mother liquid to a refining process.

However, the following problems exist in the whole reaction process:

1. in the process of adding hydrogen for reaction, the temperature and the pressure in the hydrogenation kettle are controlled by adding steam or cooling water into the jacket of the hydrogenation kettle, the heat exchange effect is poor, the temperature is unstable and is not easy to control, the conversion rate and the purity of the product are influenced, and the safety of the system is reduced.

2. The method of adding hydrogen into the bottom of the hydrogenation kettle is not beneficial to maintenance and operation, and the added hydrogen is not uniformly distributed, so that the efficiency of hydrogenation reaction is influenced, the consumption of hydrogen is increased, and the benefit is reduced.

3. When the reaction product is discharged from the bottom of the hydrogenation kettle, the reaction product is required to be filtered in each batch, the noble metal catalyst is taken out from the filter and then put into the hydrogenation kettle for recycling, the loss of the noble metal catalyst is increased, the service life of the noble metal catalyst is shortened, and meanwhile, the process usually adopts manual feeding, so that the labor intensity of workers is increased, the requirement of closed production cannot be met, and the safety of the system is reduced.

Therefore, there is a need to provide a hydrogenation reaction apparatus capable of solving the problems as described above.

Disclosure of Invention

The invention aims to provide a hydrogenation reaction device which has the advantages of fast heat transfer, stable temperature control, realization of self circulation of a heat exchange medium, energy conservation, more uniform mixing of hydrogen and materials, fast mass transfer, reduction of hydrogen consumption, improvement of the conversion rate and purity of products, prolongation of the service life of a noble metal catalyst, reduction of the loss of the noble metal catalyst, achievement of the requirement of closed production, reduction of labor intensity of workers, higher automation degree, easy operation and control and improvement of system safety.

In order to achieve the above object, an aspect of the present invention provides a hydrogenation reaction system, comprising: the device comprises a hydrogenation kettle, wherein a kettle body of the hydrogenation kettle is respectively connected with a feeding pipe, a hydrogenation pipe, a vacuum pipe, a nitrogen pipe and a product discharge pipe, the outer wall of the hydrogenation kettle is provided with a hydrogenation kettle jacket, and a stirrer is arranged inside the hydrogenation kettle; the cooling unit comprises a cooling pipeline arranged inside the hydrogenation kettle and a condenser arranged outside the hydrogenation kettle, and an inlet and an outlet of the cooling pipeline are communicated with an outlet and an inlet of the condenser respectively.

Preferably, a multifunctional pipe is further arranged inside the hydrogenation kettle, one end of the multifunctional pipe is connected with the hydrogenation pipe, the other end of the multifunctional pipe is connected with a distributor, and the product discharge pipe is connected to the multifunctional pipe.

Preferably, the end of the multifunctional pipe connected with the distributor extends to the bottom of the hydrogenation kettle.

Preferably, the distributor includes a main pipe and a plurality of branch pipes, each of which is provided with a hydrogen gas discharge port.

Preferably, a microporous filter is arranged on the hydrogen discharge port.

Preferably, the hydrogen gas discharge port is provided on a lower surface of the branch pipe.

Preferably, the cooling unit comprises a cooling grid, a lower ring pipe, an upper ring pipe and a vertical pipe, the lower ring pipe and the upper ring pipe are respectively connected with the lower end and the upper end of the cooling grid, the upper ring pipe is connected with a plurality of vertical pipes, and the plurality of vertical pipes are communicated with the condenser.

Preferably, the cooling unit further comprises a top ring pipe connecting the plurality of stand pipes in a horizontal direction.

Preferably, the cooling unit further comprises a head tank, one end of the head tank is connected to the outlet of the condenser, and the other end of the head tank is connected to the inlet of the cooling pipeline.

Preferably, the hydrogenation reaction system further comprises a control unit, and the control unit can control the reaction temperature and pressure of the hydrogenation kettle and emergency stop.

The hydrogenation reaction system provided by the invention has the advantages of fast heat transfer, stable temperature control, realization of self circulation of heat exchange medium, energy saving, more uniform mixing of hydrogen and materials, fast mass transfer, reduction of hydrogen consumption, improvement of product conversion rate and purity, reduction of energy consumption, prolongation of the service life of the noble metal catalyst, reduction of the loss of the noble metal catalyst, achievement of the requirement of closed production, reduction of labor intensity of workers, higher automation degree, easiness in operation and control and high system safety.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of the structure of a hydrogenation reaction system according to the present invention;

FIG. 2 is a schematic diagram of the structure of a hydrogenation vessel of a hydrogenation reaction system according to the present invention;

FIG. 3 is a schematic diagram of the structure of a cooling unit of a hydrogenation reaction system according to the present invention;

FIG. 4 is a schematic diagram of the structure of a distributor of a hydrogenation reaction system according to the present invention.

Description of the reference numerals

1, a hydrogenation kettle; 2, a stirrer; 3, a hydrogenation kettle jacket; 4, a multifunctional pipe;

5, a distributor; 51 a main tube; 52 branch pipes;

6 a microporous filter; 7 hydrogen regulating valve; 8, a cooling medium adjusting valve;

9 cooling the calandria; 10 a condenser; 11 elevated tanks; 12, a lower ring pipe;

13, an upper ring pipe; 14 top ring pipes; 15 cooling medium manifold; 16 stand pipes;

21 a feed tube; 22 a hydrogenation tube; 23 vacuum tubes; 24 emptying the pipe;

251 a cooling water inlet pipe; 252 rows of cooling water pipes;

261 feeding a steam pipe; 262 rows of steam condensate pipes;

27 a discharge conduit; 28, introducing a cooling medium; 29 product discharge pipe;

30 a nitrogen gas pipe; 31 emergency release pipe

A, a feed inlet; b, a hydrogenation port;

c, a vacuum port; d, emptying the air;

e1 steam inlet; e2 steam outlet;

f1 cooling water inlet; an F2 cooling water outlet;

g, a discharge port; a water inlet H; a J product discharge port;

k a cooling medium discharge port; an L cooling medium inlet; m nitrogen port; n Emergency relief opening

Detailed Description

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in describing the present invention, in the case where it is judged that the description for the related well-known function or structure may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted.

Fig. 1 is a schematic view of the overall structure of a hydrogenation reaction system according to the present invention, fig. 2 is a schematic view of the structure of a hydrogenation kettle of a hydrogenation reaction system according to the present invention, fig. 3 is a schematic view of the overall structure of a cooling unit of a hydrogenation reaction system according to the present invention, and fig. 4 is a schematic view of the structure of a distributor in a top view direction in a hydrogenation reaction system according to the present invention.

The hydrogenation reaction system provided by the invention comprises a hydrogenation kettle 1 and a cooling unit. A reduction product is produced in the hydrogenation vessel 1, the hydrogenation reaction is an exothermic reaction, and a cooling unit is used to cool the reaction material so that the temperature inside the hydrogenation vessel 1 is maintained at the reaction temperature. Hereinafter, the hydrogenation vessel 1 and the cooling unit will be described in detail, respectively.

As shown in fig. 1 and fig. 2, the body of the hydrogenation reactor 1 is preferably made of stainless steel, and the body is connected with a feeding pipe 21, a hydrogenation pipe 22, a vacuum pipe 23, a nitrogen pipe 30 and a product discharge pipe 29, respectively, and each pipe is provided with a valve for controlling the opening and closing or adjusting the flow of the material. As shown in fig. 2, the hydrogenation reactor 1 is provided with a feed port a, a hydrogenation port B, a vacuum port C, and a nitrogen port M on the reactor lid for connecting the feed pipe 1, the hydrogenation pipe 22, the vacuum pipe 23, and the nitrogen pipe 30, respectively, and a product discharge port J on the side wall of the hydrogenation reactor 1 for connecting the product discharge pipe 29. Thus, the raw material and the catalyst are fed into the interior of hydrogenation reactor 1 through feed tube 1, hydrogen gas is fed into the interior of hydrogenation reactor 1 through hydrogenation tube 22, the interior of hydrogenation reactor 1 is evacuated through vacuum tube 23, nitrogen gas is fed into the interior of hydrogenation reactor 1 through nitrogen gas tube 30 to displace air or apply pressure to the reaction liquid level (this section will be described in detail below), and the product is discharged to the exterior of hydrogenation reactor 1 through product discharge tube 29. In addition, a drain port D may be further disposed on the kettle cover of the hydrogenation kettle 1, the drain port D is connected to the drain pipe 24 (an emergency drain pipe 31 may also be disposed to serve as an emergency (safety) drain port N), and when an abnormal condition (for example, an excessive pressure) occurs inside the hydrogenation kettle 1, the drain port D may be drained in an emergency. In addition, the bottom of the hydrogenation kettle 1 is provided with a discharge opening G, a discharge pipe 27 is connected to the discharge opening G, and the noble metal catalyst or the discharged material can be discharged through the discharge pipe 27.

On the basis, a hydrogenation kettle jacket 3 is arranged on the outer wall of the hydrogenation kettle 1, the hydrogenation kettle jacket 3 comprises a first opening arranged at the upper part of the hydrogenation kettle jacket 3 and a second opening arranged at the lower part of the hydrogenation kettle jacket 3, the first opening is used as a steam inlet E1 and a cooling water outlet F2, a steam inlet pipe 261 and a cooling water outlet pipe 252 are connected in parallel to the first opening, the second opening is used as a steam outlet E2 and a cooling water inlet F1, and a steam outlet condensate pipe 262 and a cooling water inlet pipe 251 are connected in parallel to the second opening. Through hydrogenation cauldron jacket 3, let in steam so that 1 inside reaction temperature that reaches of hydrogenation cauldron for the reactant effectively reacts, perhaps can let in cooling water, with cooling hydrogenation cauldron 1 on the outer wall of hydrogenation cauldron 1, thereby absorb the heat of giving off among the reaction sequence.

In addition, hydrogenation cauldron 1 is inside to be provided with agitator 2 to stir reaction mass, make reaction mass and hydrogen abundant contact reaction, improve reaction efficiency and productivity. The stirrer 2 is connected with a driving source M arranged outside the hydrogenation kettle 1 so as to stir reaction substances at a constant speed or at a variable speed. The stirrer 2 is preferably disposed between an upper loop 12 and a lower loop 13, which will be described later, so that the reactant and the cooling line are in sufficient contact to exchange heat. The stirrer is preferably a disk turbine type stirrer, which causes highly turbulent radial flow when rotating, and has high stirring efficiency, so that the reaction substance has sufficient time to exchange heat with the cooling medium in the cooling pipeline.

In the present invention, in order to stably control the reaction temperature in the hydrogenation reactor 1, the hydrogenation reaction system of the present invention further includes a cooling unit. The cooling unit comprises a cooling pipeline arranged inside the hydrogenation kettle 1 and a condenser 10 arranged outside the hydrogenation kettle 1, wherein the inlet and the outlet of the cooling pipeline are respectively communicated with the outlet and the inlet of the condenser 10. In the state that the hydrogenation reactor 1 is operated, a cooling material is circulated in the cooling unit. Specifically, liquid cooling medium flows in a cooling pipeline in the hydrogenation kettle 1, in the process, the liquid cooling medium can absorb heat in the hydrogenation reaction, the reaction substance is cooled while the liquid cooling medium is gasified, the hydrogenation reaction can be carried out within a certain temperature range, the gasified cooling medium is discharged from an outlet of the cooling pipeline to the outside of the hydrogenation kettle 1, and then exchanges heat with water and air in a condenser 10 communicated with the cooling pipeline and is converted into liquid, so that self-circulation of the heat exchange medium can be realized, and energy is saved.

In the present invention, methanol is selected as a cooling medium as a preferred embodiment. In the embodiment of the invention for preparing 3, 4-dichloroaniline by using a hydrogenation reaction system, the melting point of 3, 4-dichloronitrobenzene used as a raw material is 39-41 ℃, the melting point of 3, 4-dichloroaniline is 69-71 ℃, the boiling point of methanol at normal pressure is 64.7 ℃, and methanol is used as a cooling medium in the reduction reaction, so that methanol is gasified to absorb heat, and a good cooling effect can be achieved. However, the present invention is not limited to the type of the cooling medium, and other cooling materials may be used.

In the present invention, as an embodiment of the cooling unit, as shown in fig. 1 and 2, the cooling unit may include a cooling calandria 9, a lower ring pipe 12, an upper ring pipe 13, and a riser pipe 16, the lower ring pipe 12 and the upper ring pipe 13 are respectively connected to the lower end and the upper end of the cooling calandria 9, the upper ring pipe 13 is connected to a plurality of riser pipes 16, and the plurality of riser pipes 16 extend to the outside of the hydrogenation reactor 1 through a cooling medium discharge port K and communicate with the condenser 10.

The cooling rack pipe 9 is a pipeline formed by combining a plurality of groups of thin pipes, the plurality of groups of thin pipes can be uniformly arranged in a square or round shape, but not limited to this, and each group of thin pipes comprises a plurality of thin pipes. The lower ring pipe 12 makes the liquid cooling medium evenly distributed along the horizontal direction, the upper ring pipe 13 makes the gaseous cooling medium collect, makes the gaseous pressure balance, the riser 16 connects the upper ring pipe 13 and the cooling medium manifold 15, as shown in fig. 1, three risers 16 are connected to the cooling medium manifold 15 in parallel outside the hydrogenation kettle 1, and the cooling medium manifold 15 is connected to the condenser 10.

In the present invention, the cooling rows 9 and the plurality of vertical tubes 16 are vertically arranged to cool the reaction mass in the vertical direction, and the upper and

lower loops

13 and 12 are horizontally arranged to cool the reaction mass in the horizontal direction, whereby the reaction mass can be cooled in all directions.

Furthermore, as shown in fig. 1, 2 and 4, the cooling unit may further include a top ring pipe 14, and the top ring pipe 14 is connected to a plurality of stand pipes 16 in a horizontal direction. It is to be noted herein that in the hydrogenation reactor 1, there are a liquid phase portion and a gas phase portion above the liquid phase, and the top loop 14 is preferably disposed in the gas phase portion, so as to cool the gas phase portion, and to facilitate the gas phase pressure balance of the cooling medium, and to facilitate the uniform distribution of the cooling medium.

The condenser 10 may be an evaporative condenser, the gaseous cooling medium delivered through the cooling medium manifold 15 enters the tube side portion of the condenser 10, and the shell side portion of the condenser 10 is introduced with cooling water through the water inlet H to condense the gaseous cooling medium into a liquid state, so that the liquid cooling medium enters the hydrogenation kettle 1 again for cooling operation. The condenser 10 may be provided with a liquid level detection and water inlet switch valve and the like and interlocked to control the liquid level.

In addition, in order to realize the self-circulation of the cooling medium, the cooling unit may further include a high-level tank 11, one end of the high-level tank 11 is connected to the outlet of the condenser 10, and the other end of the high-level tank 11 is connected to the inlet of the cooling pipeline, for example, as shown in fig. 1 and 2, the inlet L of the cooling pipeline is connected to the other end of the high-level tank 11 through a cooling medium inlet pipe 28, and the cooling medium inlet pipe 28 is provided with a cooling medium regulating valve 8 to regulate the introduction amount of the cooling medium, so that the cooling effect can be effectively controlled. A temperature detector, a pressure detector, and the like may be provided on the head tank 11 to detect the temperature and pressure of the cooling medium in the head tank, and a safety relief port, a safety valve, and an emergency relief valve may be provided, so that the head tank 11 can be safely controlled.

In the present invention, the reaction substance is cooled by the cooling line, and the cooling medium is condensed by the condenser 10 to be recycled. The operation of the cooling medium (methanol is preferred in the present invention, and the present invention is described below based on methanol, but the present invention is not limited thereto) will be specifically described below based on the preferred embodiment described above: referring to fig. 1, 2 and 4, liquid methanol is introduced into the cooling pipeline through a cooling medium inlet L, after the liquid methanol enters the lower ring pipe 12 and is uniformly distributed in the horizontal direction, the liquid methanol enters each thin pipe of the cooling calandria 9 along the vertical direction to absorb heat of reaction substances near the cooling calandria 9 in the vertical direction, the liquid methanol after heat absorption is heated and gasified, the gaseous methanol is collected in the upper ring pipe 13, then enters a plurality of vertical pipes 16 and then is converged into a cooling medium header pipe 15, then is conveyed to a condenser 10, after the gaseous methanol is cooled and condensed into a liquid state again after passing through the condenser 10, the liquid methanol enters the elevated tank 11 and is sent into the cooling pipeline in the hydrogenation kettle 1 again through a cooling medium inlet pipe 28 by utilizing a head difference, and thus, one-cycle of methanol is completed. In the process, because methanol is gasified to absorb heat, the cooling pipeline is provided with a plurality of channels in the horizontal and vertical directions, compared with the previous cooling process through the hydrogenation kettle jacket 3, the cooling efficiency is improved, and the cooling effect can be more effectively and finely controlled by controlling the introduction amount of the methanol. The hydrogenation reaction system has the advantages of rapid heat transfer, small temperature difference in the hydrogenation kettle, stable temperature control, energy conservation due to self-circulation of the heat exchange medium and the like.

The present invention has the following advantages in addition to the advantages of the cooling unit described above.

As shown in fig. 1, a multifunctional pipe 4 is further disposed inside the hydrogenation reactor 1, one end of the multifunctional pipe 4 is connected to the hydrogenation pipe 22, the other end is provided with a distributor 5 and a microporous filter 6, and a product discharge pipe 29 is connected to the multifunctional pipe 4 through a product discharge port J. In fact, the multi-function tube 4 is an extension of the hydrogenation tube 22 extending to the inside of the hydrogenation reactor 1 (of course, the multi-function tube 4 may be a separate tube connected to the hydrogenation tube 22), so this portion is named as the multi-function tube 4 because this tube is used not only for passing hydrogen into the inside of the hydrogenation reactor 1 but also for discharging the product after the hydrogenation reaction is completed in the present invention. Specifically, in the reaction process, hydrogen is discharged to the reaction substance through the hydrogenation pipe 22, the multifunctional pipe 4 and the distributor 5 in sequence to participate in the reaction, after the reaction is finished, the hydrogen regulating valve 7 arranged on the hydrogenation pipe 22 is closed, then nitrogen is introduced from the nitrogen port M to perform nitrogen replacement, nitrogen is introduced to press the material, the product is pressed into the multifunctional pipe 4 from the microporous filter 6 and the distributor 5, and then is discharged to the refining process through the product discharge pipe 29, and the noble metal catalyst is intercepted by the microporous filter 6 and used for the next reaction.

In the invention, the hydrogen is introduced from the upper part of the hydrogenation kettle, thereby being beneficial to maintenance and operation, and the pipeline for introducing the hydrogen is also used as a channel for discharging the product, so that the noble metal catalyst does not need to be discharged from the bottom of the hydrogenation kettle as before, but the product is only discharged through the product discharge pipe 29 arranged at the side part of the hydrogenation kettle 1, thereby prolonging the service life of the noble metal catalyst, reducing the link of manual feeding and greatly reducing the labor intensity. And all processes can be carried out in a closed environment, so that the safety of the system is improved.

In view of the property of gas floating up, it is preferable that the end of the multi-functional pipe 4 provided with the distributor 5 extends to the bottom of the hydrogenation vessel 1, whereby hydrogen gas is introduced into the bottom of the hydrogenation vessel 1 so that the hydrogen gas is sufficiently contacted with the reaction substance to perform the reaction.

The present invention is not particularly limited as to the form of the distributor 5, and the present invention provides a preferred form of the distributor 5. As shown in fig. 4, the distributor 5 of the present invention comprises a main pipe 51 and a plurality of branch pipes 52, and each branch pipe 52 is provided with a hydrogen gas discharge port. The length of the plurality of branch pipes 52 is gradually decreased from the center toward both ends, and the number of hydrogen gas discharge ports provided in each branch pipe 52 may be designed according to the length of the branch pipe 52. Through distributor 5, hydrogen can evenly spread inside hydrogenation cauldron 1, and hydrogen and material mix more evenly, and the mass transfer is fast, has reduced hydrogen consumption, has improved product conversion rate and purity simultaneously.

On this basis, it is preferable that a hydrogen gas discharge port be provided on the lower surface of branch pipe 52, whereby hydrogen gas can be discharged downward so as to come into contact with the reaction substance as much as possible from the bottommost portion of hydrogenation vessel 1.

In addition, in order to prevent the noble metal catalyst from entering the multi-functional pipe 4 through the hydrogen discharge port during the discharge of the product, it is preferable that a micro-porous filter 6 is provided on the hydrogen discharge port. The pore diameter of the microporous filter 6 is determined according to the particle diameter of the noble metal catalyst.

In addition to the above structure, the hydrogenation reaction system of the present invention may further include a control unit capable of controlling the reaction temperature, pressure, etc. of the hydrogenation reactor 1 and achieving emergency shutdown. Specifically, the temperature, pressure, liquid level, hydrogen addition and other parameters of the materials in the hydrogenation kettle 1; the running, current and fault signal parameters of the motor of the stirrer 2; water level parameters of the condenser 10; various parameters such as temperature, pressure, liquid level parameters and the like of the head tank 11 can be connected to the control unit. For example, the temperature of the material in the hydrogenation kettle and the cooling medium regulating valve 8 can be controlled in an interlocking manner to regulate the flow of the cooling medium; the hydrogen flow and the hydrogen regulating valve 7 can be controlled in an interlocking way to regulate the hydrogen flow; the internal pressure of the hydrogenation kettle 1 and the emptying valve can be controlled in a linkage manner, and when the internal pressure of the kettle is too high, the control unit controls the opening of the emptying valve so as to discharge gas in the kettle.

In addition, for the purpose of system safety, the hydrogenation reaction system of the invention can be provided with a Safety Instrument System (SIS), and the starting conditions of logic units are as follows:

a. the temperature of the hydrogenation kettle reaches a high limit;

b. the pressure of the hydrogenation kettle reaches a high limit;

c. failure of a stirring motor of the hydrogenation kettle;

d. the emergency stop system is manually depressed.

In one of the above situations, the SIS logic initiates all of the following actions:

1. the hydrogen switch valve is cut off in a linkage manner;

2. a cooling water inlet valve and a drain valve on a pipeline connected with a hydrogenation kettle jacket are opened in a linkage manner, so that cooling water is introduced into the hydrogenation kettle jacket;

3. the emergency vent valve is opened in a linkage manner.

Therefore, when an emergency occurs, safety accidents are avoided.

In conclusion, the hydrogenation reaction system provided by the invention has the advantages of fast heat transfer, stable temperature control, realization of self circulation of a heat exchange medium, energy conservation, more uniform mixing of hydrogen and materials, fast mass transfer, reduction of hydrogen consumption, improvement of product conversion rate and purity, prolongation of the service life of the noble metal catalyst, reduction of the loss of the noble metal catalyst, achievement of the requirement of closed production, reduction of labor intensity of workers, higher automation degree, easiness in operation and control, high system safety and the like.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, numerous simple variants are possible, comprising the combination of the individual specific technical features in any suitable manner. The invention is not described in detail in order to avoid unnecessary repetition. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.

Claims

1. A hydrogenation reaction system, comprising:

the device comprises a hydrogenation kettle (1), wherein a kettle body of the hydrogenation kettle (1) is respectively connected with a feeding pipe (21), a hydrogenation pipe (22), a vacuum pipe (23), a nitrogen pipe (30) and a product discharge pipe (29), the outer wall of the hydrogenation kettle (1) is provided with a hydrogenation kettle jacket (3), and a stirrer (2) is arranged in the hydrogenation kettle (1);

the cooling unit comprises a cooling pipeline arranged inside the hydrogenation kettle (1) and a condenser (10) arranged outside the hydrogenation kettle (1), and an inlet and an outlet of the cooling pipeline are respectively communicated with an outlet and an inlet of the condenser (10);

the cooling unit comprises a cooling calandria (9), a lower ring pipe (12), an upper ring pipe (13) and stand pipes (16), the lower ring pipe (12) and the upper ring pipe (13) are respectively connected with the lower end and the upper end of the cooling calandria (9), the upper ring pipe (13) is connected with a plurality of stand pipes (16), and the stand pipes (16) are communicated with the condenser (10);

the cooling unit further comprises a top ring pipe (14), the top ring pipe (14) connecting the plurality of stand pipes (16) in a horizontal direction;

the hydrogenation kettle (1) comprises a liquid phase part and a gas phase part above the liquid phase part, and the top ring pipe (14) is arranged in the gas phase part.

2. The hydrogenation reaction system according to claim 1, wherein a multifunctional pipe (4) is further arranged inside the hydrogenation kettle (1), one end of the multifunctional pipe (4) is connected with the hydrogenation pipe (22), the other end of the multifunctional pipe is connected with a distributor (5), and the product discharge pipe (29) is connected to the multifunctional pipe (4).

3. The hydrogenation reaction system according to claim 2, wherein the end of the multifunctional pipe (4) connected with the distributor (5) extends to the bottom of the hydrogenation kettle (1).

4. The hydrogenation reaction system according to claim 2, wherein the distributor (5) comprises a main pipe (51) and a plurality of branch pipes (52), and each of the branch pipes (52) is provided with a hydrogen gas discharge port.

5. The hydrogenation reaction system according to claim 4, wherein a microporous filter (6) is disposed on the hydrogen discharge port.

6. The hydrogenation reaction system according to claim 4, wherein the hydrogen gas discharge port is provided on a lower surface of the branch pipe (52).

7. The hydrogenation reaction system according to claim 1, wherein the cooling unit further comprises a head tank (11), one end of the head tank (11) is connected to an outlet of the condenser (10), and the other end of the head tank (11) is connected to an inlet of the cooling line.

8. The hydrogenation reaction system according to claim 1, further comprising a control unit capable of controlling the reaction temperature and pressure of the hydrogenation reactor (1) and emergency shutdown.