Gas-liquid phase vinyl chloride production device and process

Abstract

The present invention provides a gas-liquid phase vinyl chloride production device and process, which belongs to the technical field of vinyl chloride production, including a reaction tower, a liquid distributor, a gas distributor, a demister, a liquid catalyst circulation mechanism, and a condenser; the reaction tower is provided with a gas-liquid reaction zone, a liquid catalyst inlet, and a liquid catalyst outlet, a mixed gas inlet at the bottom, and a reaction gas outlet at the top; the liquid distributor is arranged in the reaction tower; the gas distributor is arranged in the reaction tower; the demister is used to recover the liquid catalyst droplets entrained in the reaction gas; the liquid catalyst circulation mechanism is arranged outside the reaction tower; and the condenser is arranged outside the reaction tower, which is used to collect the reaction gas and cool it down. It is intended to solve the technical problems in the prior art that gas-solid phase reactions are often accompanied by serious temperature runaway and surface carbon accumulation, which easily cause catalyst deactivation, and there are many side reactions, and the product impurity content is high, which puts pressure on the fine manufacturing of subsequent products.

Description

Technical Field

[0001] The invention belongs to the technical field of vinyl chloride production, and more specifically, relates to a gas-liquid phase vinyl chloride production device and process. Background Art

[0002] Vinyl chloride, also known as vinyl chloride, is a type of halogenated hydrocarbon and an important raw material for the plastics industry. It is mainly used to produce polyvinyl chloride resin (PVC, the world's largest-produced general-purpose plastic). It can also be copolymerized with vinyl acetate, butadiene, acrylonitrile, acrylate, vinylidene chloride, etc. to manufacture adhesives, coatings, food packaging materials, building materials, etc. It can be used as a refrigerator due to its low boiling point. It can also be used as an extractant for dyes and spices.

[0003] At present, the main industrial synthesis methods of vinyl chloride monomer are acetylene hydrochlorination and ethylene oxychlorination. In 2017, China's PVC production capacity reached about 23 million tons, and about 80% of PVC production came from the acetylene route, accounting for about 40% of the global PVC production capacity. However, the acetylene method uses a fixed bed reactor to produce vinyl chloride. Acetylene and hydrogen chloride react on the surface of a solid catalyst. The acetylene hydrochlorination reaction is a highly exothermic reaction. Therefore, the gas-solid phase reaction is often accompanied by severe temperature runaway and surface carbon accumulation, which can easily cause catalyst deactivation, and there are many side reactions. The product has a high impurity content, which puts pressure on the subsequent product refinement. Summary of the invention

[0004] The object of the present invention is to provide a gas-liquid phase vinyl chloride production device and process, aiming to solve the technical problems of severe "temperature runaway" and surface carbon accumulation, easy catalyst deactivation, and many side reactions associated with gas-solid phase reactions in the prior art.

[0005] To achieve the above object, the technical solution adopted by the present invention is: to provide a gas-liquid phase vinyl chloride production device, comprising

[0006] A reaction tower, wherein the reaction tower is provided with two gas-liquid reaction zones filled with fillers at the upper and lower parts, the reaction tower is provided with a liquid catalyst inlet at the upper part and a liquid catalyst outlet at the lower part for circulating the liquid catalyst in and out of the reaction tower, the reaction tower is provided with a mixed gas inlet at the lower part and a reaction gas outlet at the top of the reaction tower;

[0007] A liquid distributor, arranged in the reaction tower, for distributing the liquid catalyst before entering the two gas-liquid reaction zones;

[0008] The gas distributor is arranged in the reaction tower and is used to distribute the mixed gas before entering the two gas-liquid reaction zones;

[0009] A demister, located at the top of the reaction tower, is used to recover the liquid catalyst droplets entrained in the reaction gas;

[0010] A liquid catalyst circulation mechanism is provided outside the reaction tower and is used for cooling, circulating and renewing the liquid catalyst; and

[0011] The condenser is arranged outside the reaction tower and is used to collect the reaction gas and cool it down, and to recycle the liquid catalyst droplets entrained in the reaction gas.

[0012] As another embodiment of the present application, the liquid catalyst circulation mechanism includes:

[0013] A catalyst storage tank, the bottom of which is connected to the inlet of a circulation pump through a first pipeline, the top of which is connected to the liquid catalyst outlet of a reaction tower through a second pipeline, and the first pipeline and the second pipeline are connected through a third pipeline, and valves are provided on the first pipeline, the second pipeline and the third pipeline; and

[0014] The heat exchanger has one end connected to the liquid outlet of the circulation pump and the other end connected to the liquid catalyst inlet at the top of the reaction tower.

[0015] As another embodiment of the present application, a liquid outlet is provided at the bottom of the condenser for discharging the cooled liquid catalyst, and the liquid outlet is connected to the liquid storage part at the bottom of the reaction tower through a fourth pipeline.

[0016] As another embodiment of the present application, a temperature transmitter and a pressure transmitter are provided on the upper part of the demister of the reaction tower, a temperature transmitter is provided in the gas-liquid reaction zone, a temperature control transmitter is provided in the lower gas-liquid reaction zone, a temperature transmitter and a pressure transmitter are provided on the upper part of the liquid storage part for measuring the temperature and pressure of the mixed gas, a liquid level transmitter is provided in the liquid storage part, and a liquid level transmitter is provided in the catalyst storage tank. The temperature control transmitter is used to control the regulating valve on the pipeline between the heat exchanger and the liquid catalyst inlet to adjust the flow rate of the liquid catalyst.

[0017] The gas-liquid phase vinyl chloride production process comprises the following steps:

[0018] 1) adding the liquid catalyst in the catalyst storage tank into the reaction tower through a circulation pump, then closing the inlet and outlet of the catalyst storage tank, and using the circulation pump to form a circulation system for the liquid catalyst;

[0019] 2) The raw materials hydrogen chloride A and acetylene B are mixed to form a mixed gas which enters the lower part of the reaction tower at a certain flow rate;

[0020] 3) In the reaction tower, the mixed gas moves upward after being distributed by the gas distributor, and the liquid catalyst falls downward after being distributed by the liquid distributor, and the two react in gas-liquid contact in the reaction tower to generate vinyl chloride;

[0021] 4) The generated vinyl chloride gas is further subjected to a demister and a condenser at the top of the reaction tower to remove the entrained liquid catalyst droplets to obtain a crude vinyl chloride product, and a qualified product is obtained through a subsequent refining process;

[0022] 5) Monitor the temperature of the gas-liquid reaction zone by a temperature transmitter, and control the reflux amount of the liquid catalyst by a temperature control transmitter to control the temperature of the lower gas-liquid reaction zone;

[0023] 6) When the efficiency of the liquid catalyst decreases, the catalyst is renewed by opening the inlet and outlet of the catalyst storage tank.

[0024] As another embodiment of the present application, in the step 1), the valves of the first pipeline and the third pipeline are opened, the valve of the second pipeline is closed, and the circulation pump is started to allow the liquid catalyst to enter from the liquid catalyst inlet at the top of the reaction tower, fall and form a liquid storage part at the bottom, and the liquid level of the liquid storage part is lower than the mixed gas inlet. After completion, the valve of the first pipeline is closed to complete the establishment of the liquid catalyst circulation system.

[0025] As another embodiment of the present application, the liquid catalyst is one of imidazole hydrochloride, nitrogen methyl pyrrolidone hydrochloride, choline chloride or quaternary phosphonium salt; the active component of the liquid catalyst is one of cupric chloride, cuprous chloride, tin chloride and ruthenium trichloride.

[0026] As another embodiment of the present application, the molar ratio of hydrogen chloride to acetylene in the mixed gas is (1.0-1.2):1.

[0027] As another embodiment of the present application, in step 5), the temperature of the lower gas-liquid reaction zone in the reaction tower is controlled to 130-160° C. by controlling the reflux amount of the liquid catalyst through a regulating valve provided on the pipeline between the heat exchanger and the liquid catalyst inlet.

[0028] As another embodiment of the present application, in step 6), during the reaction process, when the catalytic efficiency of the catalyst does not meet the process requirements, the valve on the second pipeline is opened to discharge part of the liquid catalyst into the catalyst tank, the valve on the second pipeline is closed, and after regeneration in the catalyst tank, the valve on the first pipeline is opened to add an equal mass of liquid catalyst into the reaction system.

[0029] The beneficial effects of the gas-liquid phase vinyl chloride production device and process of the present invention are as follows:

[0030] (1) Compared with the fixed bed reaction process, the liquid catalyst is used as the heat transfer carrier, which has a fast heat transfer speed, avoids the phenomenon of local temperature rise, avoids carbon accumulation on the catalyst surface, and improves the catalytic efficiency of the catalyst;

[0031] (2) Gas-liquid contact, short contact path and improved reaction efficiency;

[0032] (3) External circulation liquid-liquid heat exchange, small heat exchanger area, high heat exchange efficiency, and low equipment investment;

[0033] (4) High catalytic efficiency and heat exchange efficiency, which can realize equipment miniaturization and high production capacity;

[0034] (5) Tower reaction can effectively control the contact area between gas and liquid, control the rate of reaction heat generation, effectively perform temperature control, and have high production safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, 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 present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 A schematic diagram of the structure of a gas-liquid phase vinyl chloride production device provided in an embodiment of the present invention;

[0037] Figure 2 for Figure 1 Schematic diagram of the structure of the reaction tower.

[0038] In the figure: 1. reaction tower, 2. condenser, 3. regulating valve, 4. heat exchanger, 5. circulating pump, 6. catalyst storage tank, 7. liquid level transmitter, 8. mixed gas inlet, 9. gas distributor, 10. packing, 11. temperature transmitter, 12. liquid distributor, 13. demister, 14. pressure transmitter, 15. reaction gas outlet, 16. liquid catalyst inlet, 17. temperature control transmitter, 18. liquid catalyst outlet, 19. first pipeline, 20. second pipeline, 21. third pipeline, 22. fourth pipeline, 23. liquid storage part. DETAILED DESCRIPTION

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] See also Figure 1 and Figure 2 The present invention provides a gas-liquid phase vinyl chloride production device, comprising

[0041] A reaction tower 1, wherein the reaction tower 1 is provided with two gas-liquid reaction zones with fillers 10 at the upper and lower parts, the reaction tower 1 is provided with a liquid catalyst inlet 16 at the upper part, and a liquid catalyst outlet 18 at the lower part, for circulating the liquid catalyst in and out of the reaction tower 1, the reaction tower 1 is provided with a mixed gas inlet 8 at the lower part, and a reaction gas outlet 15 at the top of the reaction tower 1;

[0042] A liquid distributor 12 is provided in the reaction tower 1 and is used to distribute the liquid catalyst before entering the two gas-liquid reaction zones;

[0043] The gas distributor 9 is arranged in the reaction tower 1 and is used to distribute the mixed gas before entering the two gas-liquid reaction zones;

[0044] The demister 13 is provided at the top of the reaction tower 1 and is used to recover the liquid catalyst droplets entrained in the reaction gas;

[0045] A liquid catalyst circulation mechanism is provided outside the reaction tower 1 and is used for cooling, circulating and renewing the liquid catalyst; and

[0046] The condenser 2 is arranged outside the reaction tower 1 and is used to collect the reaction gas and cool it down, and to recycle the liquid catalyst droplets entrained in the reaction gas.

[0047] In this embodiment, the reaction tower 1 is used for gas-liquid contact and reaction. The liquid catalyst enters from the liquid catalyst inlet and is then distributed by the liquid distributor 12 and then sprinkled. A mixed gas inlet 8 is provided at the lower part of the reaction tower 1 for the mixed gas to enter. After entering, the mixed gas is distributed by the gas distributor 9 and then flows upward, thereby making full contact with the falling liquid catalyst and reacting under the action of the liquid catalyst, thereby greatly improving the efficiency of the reaction. Two packing areas, that is, two reaction contact areas, are provided in the reaction tower 1. Before the liquid and gas enter the two areas respectively, they need to pass through the liquid distributor 12 and the gas distributor 9, thereby greatly improving the contact area and making the reaction sufficient.

[0048] In order to solve the problem of reaction heat removal, the present invention adopts a form of continuously cooling and circulating liquid catalyst. The liquid catalyst heated by the reaction is cooled by a liquid catalyst circulation mechanism, so that the temperature in the reaction tower 1 is maintained within a certain temperature range to ensure the reaction efficiency. When the catalyst efficiency decreases, the catalyst can be updated to ensure the continuous, stable, safe and smooth progress of the reaction.

[0049] As a specific embodiment of the gas-liquid phase vinyl chloride production device provided by the present invention, the liquid catalyst circulation mechanism comprises:

[0050] The catalyst storage tank 6 has a bottom connected to the inlet of the circulation pump 5 through a first pipeline 19, and a top connected to the liquid catalyst outlet 18 of the reaction tower 1 through a second pipeline 20, and the first pipeline 19 and the second pipeline 20 are connected through a third pipeline 21, and valves are provided on the first pipeline 19, the second pipeline 20 and the third pipeline 21; and

[0051] One end of the heat exchanger 4 is connected to the liquid outlet of the circulation pump 5 , and the other end is connected to the liquid catalyst inlet 16 at the upper part of the reaction tower 1 .

[0052] In this embodiment, when liquid catalyst needs to be added to the reactor in the initial state, the valves of the first pipeline 19 and the third pipeline 21 are opened, the valve of the second pipeline 20 is closed, and the circulation pump 5 is started to allow the liquid catalyst to enter from the liquid catalyst inlet 16 at the top of the reaction tower 1, fall, and form a liquid storage part 23 at the bottom. The liquid level of the liquid storage part 23 is lower than the mixed gas inlet 8. After completion, the valve of the first pipeline 19 is closed to complete the establishment of the liquid catalyst circulation system.

[0053] The heat exchanger 4 is used to cool the liquid catalyst entering the reaction tower to ensure the temperature in the reaction tower 1 and prevent the temperature from being too high.

[0054] As a specific embodiment of the gas-liquid phase vinyl chloride production device provided by the present invention, a liquid outlet is provided at the bottom of the condenser 2 for discharging the cooled liquid catalyst, and the liquid outlet is connected to the liquid storage part 23 at the bottom of the reaction tower 1 through a fourth pipeline 22.

[0055] In this embodiment, the liquid catalyst droplets entrained with the reaction gas, that is, the generated vinyl chloride, need to be recovered. First, they are recovered by the demister 13 at the top of the reaction tower 1 and refluxed. Secondly, the catalyst that is not removed enters the condenser 2 with the reaction gas, condenses into large droplets when it is cold, and refluxes to the liquid storage part 23 through the pipeline. That is, this embodiment can effectively maintain the balance of the liquid catalyst in the system.

[0056] As a specific embodiment of the gas-liquid phase vinyl chloride production device provided by the present invention, a temperature transmitter 11 and a pressure transmitter 14 are provided on the upper part of the demister 13 of the reaction tower 1, the upper gas-liquid reaction zone is provided with a temperature transmitter 11, wherein the lower gas-liquid reaction zone is provided with a temperature control transmitter 17, and the upper part of the liquid storage part is provided with a temperature transmitter and a pressure transmitter for measuring the temperature and pressure of the mixed gas, the catalyst storage tank 6 is provided with a liquid level transmitter 7, and the temperature of the lower gas-liquid reaction zone is controlled by adjusting the flow rate of the liquid catalyst through the catalyst regulating valve on the pipeline of the liquid catalyst circulation mechanism.

[0057] The temperature transmitter 11 is used to display the temperature at various locations in the reaction tower 1;

[0058] The temperature control transmitter 17 is located at the packing 10 and is used to display and control the temperature of most reaction locations in the reaction tower 1. This is specifically achieved by controlling the reflux rate of the liquid catalyst. When the temperature is high, the regulating valve 3 is controlled to open wider. By increasing the reflux rate, the temperature in the reaction tower can be maintained within a specific reaction temperature range.

[0059] A pressure transmitter 14, used to display the pressure in the lower part and the upper part of the reaction tower 1;

[0060] The liquid level transmitter 7 is used to display the liquid level of the liquid catalyst in the reaction tower 1 .

[0061] The lower gas distributor 9 is used to evenly distribute the mixed gas, is located at the lower part of the reaction tower 1, and is connected to the mixed gas inlet 8. The lower temperature transmitter 11 and the pressure transmitter 14 are located at the lower part thereof, and are used to detect the pressure and temperature of the mixed gas;

[0062] The lower filler 10 is located on the upper part of the lower gas distributor 9, and a temperature control transmitter 17 is provided in the middle thereof to make the gas-liquid countercurrent contact more uniform and thorough;

[0063] The lower liquid distributor 12 has the function of collecting and distributing liquid, is located above the lower filler 10, and is used to collect the liquid catalyst dropped from the upper part and redistribute it;

[0064] The upper gas distributor 9 is located above the upper liquid distributor 12 and has a certain distance therefrom, and is used for redistributing the unreacted mixed gas;

[0065] The upper filler 10 is located above the upper gas distributor 9 and is used for the unreacted mixed gas to continue gas-liquid countercurrent contact and complete reaction. A temperature transmitter 11 is provided here.

[0066] The upper liquid distributor 12 is located above the upper filler 10 and is connected to the liquid catalyst inlet to ensure uniform distribution of the liquid catalyst.

[0067] The temperature transmitter 11, the liquid level transmitter 7, and the pressure transmitter 14 can all transmit the measured signal values ​​to the display device of the controller for intuitive reading, and the temperature control transmitter 17 can not only transmit the signal to the display device, but also transmit the signal to the controller to control the regulating valve to control the opening of the regulating valve.

[0068] The gas-liquid phase vinyl chloride production process comprises the following steps:

[0069] 1) adding the liquid catalyst in the catalyst storage tank 6 into the reaction tower 1 through the circulation pump 5, and then closing the inlet and outlet of the catalyst storage tank 6, so that the liquid catalyst forms a circulation system with the help of the circulation pump 5;

[0070] 2) The raw materials hydrogen chloride A and acetylene B are mixed to form a mixed gas which enters the lower part of the reaction tower 1 at a certain flow rate;

[0071] 3) In the reaction tower 1, the mixed gas moves upward after being distributed by the gas distributor 9, and the liquid catalyst falls downward after being distributed by the liquid distributor 12, and the two react in gas-liquid contact in the reaction tower 1 to generate vinyl chloride;

[0072] 4) The generated vinyl chloride gas is further subjected to the demister 13 at the top of the reaction tower 1 and the condenser 2 to remove the entrained liquid catalyst droplets to obtain a crude vinyl chloride product, and a qualified product is obtained through a subsequent refining process;

[0073] 5) The temperature of the gas-liquid reaction zone is monitored by the temperature transmitter 11, and the temperature of the lower gas-liquid reaction zone is controlled by controlling the reflux amount of the liquid catalyst;

[0074] 6) When the catalytic efficiency of the liquid catalyst decreases, the catalyst is renewed by opening the inlet and outlet of the catalyst storage tank 6 .

[0075] In this embodiment, after the mixed gas completes most of the reaction at the lower filler 10 through gas-liquid countercurrent contact under the action of the liquid catalyst, the unreacted mixed gas continues to move upward, is redistributed through the upper gas distributor 9, and continues to undergo gas-liquid countercurrent contact at the upper filler 10 until the reaction is complete.

[0076] When the liquid catalyst enters the lower packing 10 from top to bottom, it needs to be redistributed through the upper liquid distributor 12 and the lower liquid distributor 12 to make the liquid distribution more uniform.

[0077] When the liquid catalyst falls to the bottom of the reaction tower 1, the reaction heat will increase the temperature of the liquid catalyst, which is transported by the circulation pump 5 and cooled to 100-110°C by the heat exchanger 4. The temperature in the reaction tower 1 is controlled by the flow rate of the liquid catalyst refluxed into the reaction tower 1; the reflux rate of the liquid catalyst is greater than the amount of liquid catalyst required for the mixed gas reaction.

[0078] As a specific implementation mode of the gas-liquid phase vinyl chloride production process provided by the present invention, in the step 1), the valves of the first pipeline 19 and the third pipeline 21 are opened, the valve of the second pipeline 20 is closed, and the circulation pump 5 is started to allow the liquid catalyst to enter from the liquid catalyst inlet at the upper part of the reaction tower 1, fall, and form a liquid storage part 23 at the bottom, wherein the liquid level of the liquid storage part 23 is lower than the mixed gas inlet 8. After completion, the valve of the first pipeline 19 is closed to complete the establishment of the catalyst circulation system.

[0079] As a specific implementation of the gas-liquid phase vinyl chloride production process provided by the present invention, the liquid catalyst is one of imidazole hydrochloride, nitrogen methyl pyrrolidone hydrochloride, choline chloride or quaternary phosphonium salt; the active component of the liquid catalyst is one of cupric chloride, cuprous chloride, stannic chloride and ruthenium trichloride.

[0080] As a specific implementation of the gas-liquid phase vinyl chloride production process provided by the present invention, the molar ratio of hydrogen chloride to acetylene in the mixed gas is (1.0-1.2):1.

[0081] As a specific implementation of the gas-liquid phase vinyl chloride production process provided by the present invention, in the step 5), the reflux amount of the liquid catalyst is controlled by the regulating valve 3 arranged on the pipeline between the heat exchanger 4 and the liquid catalyst inlet 16 to control the temperature of the middle and lower part of the reaction tower 1 to 130-160°C.

[0082] As a specific implementation mode of the gas-liquid phase vinyl chloride production process provided by the present invention, in the step 6), during the reaction process, when the catalytic efficiency of the catalyst does not meet the process requirements, the valve on the second pipeline 20 is opened to discharge part of the liquid catalyst into the catalyst storage tank 6, the valve on the second pipeline 20 is closed, and after regeneration in the catalyst storage tank, the valve on the first pipeline 19 is opened to add the same mass of liquid catalyst into the reaction system.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A gas-liquid phase vinyl chloride production device, characterized in that: include A reaction tower, wherein the reaction tower is provided with two gas-liquid reaction zones filled with fillers at the upper and lower parts, the reaction tower is provided with a liquid catalyst inlet at the upper part and a liquid catalyst outlet at the lower part for circulating the liquid catalyst in and out of the reaction tower, the reaction tower is provided with a mixed gas inlet at the lower part and a reaction gas outlet at the top of the reaction tower; A liquid distributor, arranged in the reaction tower, for distributing the liquid catalyst before entering the two gas-liquid reaction zones; The gas distributor is arranged in the reaction tower and is used to distribute the mixed gas before entering the two gas-liquid reaction zones; A demister, located at the top of the reaction tower, is used to recover the liquid catalyst droplets entrained in the reaction gas; The liquid catalyst circulation mechanism is arranged outside the reaction tower and is used for cooling, circulating and renewing the liquid catalyst; as well as The condenser is arranged outside the reaction tower and is used to collect the reaction gas and cool it down, and to recycle the liquid catalyst droplets entrained in the reaction gas.

2. The gas-liquid phase vinyl chloride production device according to claim 1, characterized in that: The liquid catalyst circulation mechanism comprises: A catalyst storage tank, the bottom of which is connected to the inlet of a circulation pump through a first pipeline, the top of which is connected to the liquid catalyst outlet of a reaction tower through a second pipeline, and the first pipeline and the second pipeline are connected through a third pipeline, and valves are provided on the first pipeline, the second pipeline and the third pipeline; and The heat exchanger has one end connected to the liquid outlet of the circulation pump and the other end connected to the liquid catalyst inlet at the top of the reaction tower.

3. The gas-liquid phase vinyl chloride production device according to claim 2, characterized in that: The bottom of the condenser is provided with a liquid outlet for discharging the cooled liquid catalyst, and the liquid outlet is connected to the liquid storage part at the bottom of the reaction tower through a fourth pipeline.

4. The gas-liquid phase vinyl chloride production device according to claim 3, characterized in that: A temperature transmitter and a pressure transmitter are provided on the upper part of the demister of the reaction tower, a temperature transmitter is provided on the upper gas-liquid reaction zone, and a temperature control transmitter is provided on the lower gas-liquid reaction zone. A temperature transmitter and a pressure transmitter are provided on the upper part of the liquid storage part for measuring the temperature and pressure of the mixed gas. A liquid level transmitter is provided on the liquid storage part, and a liquid level transmitter is provided on the catalyst storage tank. The temperature control transmitter is used to control the regulating valve on the pipeline between the heat exchanger and the liquid catalyst inlet to adjust the flow rate of the liquid catalyst.

5. A gas-liquid phase vinyl chloride production process, characterized in that: The gas-liquid phase vinyl chloride production device according to any one of claims 2 to 4 comprises the following steps: 1) adding the liquid catalyst in the catalyst storage tank into the reaction tower through a circulation pump, then closing the inlet and outlet of the catalyst storage tank, and using the circulation pump to form a circulation system for the liquid catalyst; 2) The raw materials hydrogen chloride A and acetylene B are mixed to form a mixed gas which enters the lower part of the reaction tower at a certain flow rate; 3) In the reaction tower, the mixed gas moves upward after being distributed by the gas distributor, and the liquid catalyst falls downward after being distributed by the liquid distributor. The two react in gas-liquid contact in the reaction tower to generate vinyl chloride; 4) The generated vinyl chloride gas is further removed from the liquid catalyst droplets carried by the demister and condenser at the top of the reaction tower to obtain a crude vinyl chloride product, which is then refined to obtain a qualified product; 5) Monitor the temperature of the gas-liquid reaction zone through a temperature transmitter, and control the reflux rate of the liquid catalyst through a temperature control transmitter to control the temperature of the lower gas-liquid reaction zone; 6) When the efficiency of the liquid catalyst decreases, the catalyst is renewed by opening the inlet and outlet of the catalyst storage tank.

6. The gas-liquid phase vinyl chloride production process according to claim 5, characterized in that: In the step 1), the valves of the first pipeline and the third pipeline are opened, the valve of the second pipeline is closed, and the circulation pump is started to allow the liquid catalyst to enter from the liquid catalyst inlet at the top of the reaction tower, fall and form a liquid storage part at the bottom, and the liquid level of the liquid storage part is lower than the mixed gas inlet. After completion, the valve of the first pipeline is closed to complete the establishment of the liquid catalyst circulation system.

7. The gas-liquid phase vinyl chloride production process according to claim 5, characterized in that: The liquid catalyst is one of imidazole hydrochloride, nitrogen methyl pyrrolidone hydrochloride, choline chloride or quaternary phosphonium salt; the active component of the liquid catalyst is one of cupric chloride, cuprous chloride, tin chloride and ruthenium trichloride.

8. The gas-liquid phase vinyl chloride production process according to claim 5, characterized in that: The molar ratio of hydrogen chloride to acetylene in the mixed gas is (1.0-1.2):

1.

9. The process for producing vinyl chloride in gas-liquid phase according to claim 5, characterized in that: In the step 5), the temperature of the gas-liquid reaction zone in the lower part of the reaction tower is controlled to be 130-160° C. by controlling the reflux amount of the liquid catalyst through a regulating valve disposed on the pipeline between the heat exchanger and the liquid catalyst inlet.

10. The gas-liquid phase vinyl chloride production process according to claim 5, characterized in that: In the step 6), during the reaction process, when the catalytic efficiency of the catalyst does not meet the process requirements, the valve on the second pipeline is opened to discharge part of the liquid catalyst into the catalyst tank, the valve on the second pipeline is closed, and after regeneration in the catalyst tank, the valve on the first pipeline is opened to add the same mass of liquid catalyst into the reaction system.

Images