Reactor for synthesizing vinyl chloride and system for synthesizing vinyl chloride

Abstract

The utility model relates to the technical field of reactors, in particular to a reactor for synthesizing vinyl chloride and a system for synthesizing vinyl chloride. The reactor shell comprises a cylindrical barrel, an upper sealing head and a lower sealing head; an upper top plate is fixedly arranged between the cylinder body and the upper sealing head; a lower bottom plate is fixedly arranged between the cylinder body and the lower sealing head; a plurality of heat exchange tubes are fixedly connected between the upper top plate and the lower bottom plate; the heat exchange tubes are of a hollow structure, and a hollow core tube with the two ends closed is arranged in the center of each heat exchange tube. The core tube is movably connected in the heat exchange tube through a positioning sheet; and the core tube and the positioning sheet are fixedly and / or movably connected.

Description

Technical Field

[0001] The utility model relates to the technical field of reactors, in particular to a reactor for synthesizing vinyl chloride and a system for synthesizing vinyl chloride. Background Art

[0002] A heat exchanger is a device that transfers part of the energy of a hot fluid to a cold fluid. A shell and tube heat exchanger includes a tube shell and a tube bundle. The tube bundle is arranged inside the tube shell. A high-temperature fluid is passed through the tube bundle and a low-temperature fluid is passed through the tube shell. Alternatively, a low-temperature fluid is passed through the tube bundle and a high-temperature fluid is passed through the tube shell. The heat between the high-temperature fluid and the low-temperature fluid is conducted through the tube wall of the tube bundle, thereby achieving heat exchange between the high-temperature fluid and the low-temperature fluid.

[0003] Most of the existing technologies use vertical shell and tube heat exchangers as reactors for synthesizing vinyl chloride, and the catalyst is loaded in the tube side. Vinyl chloride monomer (VCM) is the main raw material for synthesizing polyvinyl chloride. There are two main VCM synthesis routes: acetylene method (also known as calcium carbide method) and ethylene method. In China, the coal-based acetylene method is the mainstream process for PVC production. The mixed gas enters the tube side of the reactor, and acetylene gas and hydrogen chloride react to produce vinyl chloride under the catalytic action of the catalyst, and the reaction heat is taken away by the boiling of the shell side refrigerant. This heat exchange tube structure and cooling method can prevent the catalyst from being non-uniformly deactivated, and remove the reaction heat in time, so that the reaction temperature is kept within the range required by the process, achieving the effects of improving synthesis efficiency, reducing production costs, extending equipment service life and fully utilizing the catalyst.

[0004] Most of the catalysts currently available on the market are in the form of particles, which are loaded into the tube of a vertical shell-and-tube reactor. Acetylene and hydrogen chloride react in the gas phase under the action of the catalyst to synthesize vinyl chloride. As the reaction time increases, the activity of the catalyst gradually decreases, and the corresponding vinyl chloride output decreases accordingly. It is necessary to stop the process frequently to replace the catalyst, which increases production costs and causes waste of resources in many aspects. In addition, in the prior art, when a vertical shell-and-tube heat exchanger is used as a reactor for synthesizing vinyl chloride, the temperature in the heat exchanger is controlled to reduce the evaporation of the catalyst, prevent a large change in the radial temperature gradient, and avoid the formation of hot spots in the heat exchange tubes, which causes the catalyst to be non-uniformly deactivated. In addition to the moisture and impurities brought by the raw gas, the main reason for the catalyst to lose its activity is that the catalyst evaporates from the activated carbon particles and leaves the reactor with the product gas flow. This ultimately leads to low vinyl chloride yield and production rate, and incomplete catalyst utilization causes waste.

[0005] Based on the above-mentioned prior art, there are technical problems in the prior art that need to be solved urgently, such as when a vertical shell and tube heat exchanger is used as a reactor for synthesizing vinyl chloride, the yield and production rate of vinyl chloride are greatly affected by the shape and stacking density of the catalyst particles in the tube, the catalyst is easy to evaporate or deactivate, resulting in low vinyl chloride yield and production rate, incomplete catalyst utilization causing waste, etc. Utility Model Content

[0006] In order to solve the above technical problems, the utility model provides a reactor for synthesizing vinyl chloride, the reactor comprising a reactor shell;

[0007] The reactor shell includes a cylindrical body, an upper end cap and a lower end cap; the upper end cap and the lower end cap are respectively fixedly connected to the two ends of the body;

[0008] An upper top plate is fixed between the cylinder and the upper head, and a lower bottom plate is fixed between the cylinder and the lower head;

[0009] The upper top plate is provided with a plurality of first communication ports; the lower bottom plate is provided with a plurality of second communication ports; a plurality of heat exchange tubes are fixedly connected between the upper top plate and the lower bottom plate; the central axis of the heat exchange tube is parallel to the central axis of the cylinder; the two ends of the heat exchange tube are respectively connected to the first communication port and the second communication port;

[0010] The heat exchange tube is a hollow structure. A hollow core tube with closed ends is arranged in the center of each heat exchange tube. The core tube is movably connected to the heat exchange tube through a positioning plate. The core tube and the positioning plate are fixedly and / or movably connected.

[0011] Furthermore, the areas of the upper top plate and the lower bottom plate are the same, which is equal to the cross-sectional area of ​​the cylinder, and the upper top plate and the lower bottom plate are both circular structures.

[0012] Furthermore, the length of the core tube is equal to the length of the heat exchange tube, so as to enhance the structural stability of the reactor during the reaction process.

[0013] Furthermore, the outer diameter of the core tube is smaller than the inner diameter of the heat exchange tube, and a reaction zone is formed between the core tube and the heat exchange tube. The reaction zone is filled with a catalyst. The reaction zone is used to prevent a large change in the radial temperature gradient in the heat exchange tube, which may cause non-uniform deactivation of the catalyst in the radial plane. The catalyst constitutes a catalyst bed in the reaction zone in each heat exchange tube.

[0014] Furthermore, both ends of the heat exchange tube are provided with a detachable intercepting net with a hole structure, the pore size of the hole structure is smaller than the particle size of the catalyst, so as to fix the catalyst in the reaction zone of the heat exchange tube and enable the reaction raw materials to pass through the reaction zone for sufficient reaction, thereby preventing the catalyst from scattering outside the heat exchange tube and affecting the efficiency of the catalytic reaction.

[0015] Furthermore, the length ratio of the outer diameter of the core tube to the inner diameter of the heat exchange tube is (10-15):(17-60).

[0016] Furthermore, the positioning piece is provided with three engaging pieces, and the angle between each adjacent engaging piece is 120°.

[0017] Furthermore, the upper top plate is provided with a snap-fitting groove for snapping the positioning piece at each of the first connecting ports, which is used to snap the snap-fitting piece of the positioning piece into the snap-fitting groove, thereby fixing the core tube at the center position of the heat exchange tube to further enhance the stability of the core tube in the heat exchange tube.

[0018] Furthermore, the number of the first communicating ports and the second communicating ports are equal, the shapes of the first communicating ports and the second communicating ports are both circular structures, and the areas of the first communicating ports and the second communicating ports are equal.

[0019] Furthermore, each of the heat exchange tubes is provided with a thermocouple to measure the axial temperature and radial temperature changes on the catalyst bed, so as to timely observe the changes in the catalyst bed temperature in the reaction zone.

[0020] Furthermore, the upper cover is also provided with a temperature measuring port, and the temperature measuring port is used for installing and removing the thermocouple.

[0021] Furthermore, the outer diameter of the heat exchange tube is smaller than the inner diameter of the cylinder.

[0022] Furthermore, several of the heat exchange tubes are divided into multiple groups of heat exchange tube groups, each group of the heat exchange tube groups includes several heat exchange tubes distributed in a circular shape, and the multiple groups of heat exchange tube groups are distributed in the cylinder from the inside to the outside with the central axis of the cylinder as the center, and the spacing between each adjacent heat exchange tube in the same group of the heat exchange tube groups is the same.

[0023] Furthermore, a first material inlet and outlet pipe is provided on the upper sealing head, and a central axis of the first material inlet and outlet pipe is parallel to a central axis of the cylinder.

[0024] Furthermore, a second material inlet and outlet pipe is provided on the lower head, and a central axis of the second material inlet and outlet pipe is parallel to a central axis of the cylinder.

[0025] Furthermore, when the first material is fed into the inlet and outlet pipe, the second material is discharged from the inlet and outlet pipe; conversely, when the second material is fed into the inlet and outlet pipe, the first material is discharged from the inlet and outlet pipe;

[0026] That is, the reaction raw materials can be fed from the first material inlet and outlet pipe and discharged from the second material inlet and outlet pipe; or they can be fed from the second material inlet and outlet pipe and discharged from the first material inlet and outlet pipe; the catalyst with higher activity in the reaction zone is fully utilized, the utilization rate of the catalyst is improved, and the service life of the catalyst is extended.

[0027] Furthermore, the reactor is also provided with a pipeline for adjusting the flow direction of the reaction raw materials, and the pipeline is connected to the first material inlet and outlet pipe and the second material inlet and outlet pipe.

[0028] Furthermore, the upper cover is provided with a manhole to facilitate maintenance of the reactor or disassembly and installation of the core tube.

[0029] Furthermore, the cylinder is provided with a refrigerant inlet at one end close to the lower head, and a refrigerant outlet at one end close to the upper head.

[0030] Furthermore, an overflow device is also provided on the cylinder, and the overflow device includes an overflow vertical pipe and an overflow outlet connected to one end of the overflow vertical pipe, the overflow vertical pipe is located in the cylinder, the overflow outlet is located on the side wall of the cylinder, the other end of the overflow vertical pipe is an overflow inlet, the distance between the overflow inlet and the upper top plate is smaller than the distance between the refrigerant outlet and the upper top plate, and the overflow device is used to maintain the liquid level of the refrigerant in the reactor.

[0031] Furthermore, the cylinder is provided with a shell-side gas vent near the upper top plate, and the cylinder is provided with a shell-side waste discharge port near the lower bottom plate.

[0032] Furthermore, an annular support is fixed on the side of the cylinder for fixing the reactor.

[0033] Furthermore, the annular support, the upper head and the lower head are provided with a plurality of lifting ears.

[0034] Furthermore, the diameter of the cylinder is 1.5-4.0m.

[0035] Furthermore, the wall thickness of the cylinder is 20-30 mm.

[0036] Furthermore, the outer diameter of the heat exchange tube is 40-55 mm, and the wall thickness is 3-4 mm.

[0037] Furthermore, the diameter of the manhole is 500 mm.

[0038] The utility model also provides a system for synthesizing vinyl chloride, which comprises the above-mentioned reactor for synthesizing vinyl chloride, a reaction raw material supply device, a vinyl chloride collection device, a refrigerant circulation device, and a reaction raw material gas flow regulating valve.

[0039] Furthermore, the refrigerant circulation device includes a refrigerant storage device, a circulation pipeline, and a supplementary refrigerant pipeline.

[0040] Furthermore, a reaction raw material sampling port is provided between the reactor and the vinyl chloride collecting device.

[0041] The beneficial effects of the utility model are:

[0042] 1. The utility model provides a reactor for synthesizing vinyl chloride. The single reactor has a large production capacity. The heat exchange tubes loaded with catalysts and the core tubes matched with the heat exchange tubes are concentric double-layer tubes. The resistance in the reaction is basically the same, and the gas is evenly distributed. It has the characteristics of high production intensity, high conversion rate, long equipment life and complete catalyst utilization. Compared with the converters used in domestic production processes, the production capacity of a single reactor is more than 1.5 to 2 times;

[0043] 2. The outer diameter of the core tube of the utility model is smaller than the inner diameter of the heat exchange tube. A reaction zone is formed between the core tube and the heat exchange tube. The reaction zone is filled with a catalyst. The reaction zone is used to prevent the radial temperature gradient in the heat exchange tube from changing too much, causing the catalyst in the radial plane to be non-uniformly deactivated;

[0044] 3. Both ends of the heat exchange tube of the utility model are provided with a detachable intercepting net with a hole structure, the hole diameter of the hole structure is smaller than the particle diameter of the catalyst, so as to fix the catalyst in the reaction zone of the heat exchange tube and allow the reaction raw materials to pass through the reaction zone for full reaction, thereby preventing the catalyst from scattering outside the heat exchange tube and affecting the efficiency of the catalytic reaction;

[0045] 4. The core tube of the utility model is movably connected to the heat exchange tube through the positioning piece, and the upper top plate is provided with a clamping groove for clamping the positioning piece at each of the first communication ports, which is used to clamp the clamping piece of the positioning piece in the clamping groove, thereby fixing the core tube at the center position of the heat exchange tube, so as to further enhance the stability of the core tube in the heat exchange tube;

[0046] 5. The utility model adjusts the flow direction of the reaction raw materials through the pipeline to replace the inlet and outlet of the reaction raw materials. When the first material inlet and outlet pipe is feeding, the second material inlet and outlet pipe is discharging; on the contrary, when the second material inlet and outlet pipe is feeding, the first material inlet and outlet pipe is discharging; that is, the reaction raw materials can be fed from the first material inlet and outlet pipe and discharged from the second material inlet and outlet pipe; or fed from the second material inlet and outlet pipe and discharged from the first material inlet and outlet pipe; the catalyst with higher activity in the reaction zone is fully utilized to improve the utilization rate of the catalyst and extend the service life of the catalyst;

[0047] 6. The cylinder of the utility model is also provided with an overflow device, which includes an overflow vertical pipe and an overflow outlet connected to one end of the overflow vertical pipe. The overflow vertical pipe is located in the cylinder, and the overflow outlet is located on the side wall of the cylinder. The other end of the overflow vertical pipe is an overflow inlet. The distance between the overflow inlet and the upper top plate is smaller than the distance between the refrigerant outlet and the upper top plate. The overflow device is used to maintain the liquid level of the refrigerant in the reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is a schematic cross-sectional view of the reactor structure for synthesizing vinyl chloride in Example 1 of the utility model;

[0049] Figure 2 This is a schematic diagram of the position structure of the heat exchange tube and the core tube in Example 1 of the utility model;

[0050] Figure 3 This is a schematic diagram of the structure of the positioning piece in Example 1 of the utility model;

[0051] Figure 4 for Figure 2 A partial enlarged view of middle A;

[0052] 1. Cylinder; 2. Upper head; 3. Lower head; 4. Upper top plate; 5. Lower bottom plate; 6. Heat exchange tube; 7. Core tube; 8. Positioning plate; 9. Temperature measuring port; 10. First material inlet and outlet pipe; 11. Second material inlet and outlet pipe; 12. Manhole; 13. Refrigerant inlet; 14. Refrigerant outlet; 15. Overflow device; 1501. Overflow vertical pipe; 1502. Overflow outlet; 16. Shell side gas vent; 17. Shell side waste discharge port; 18. Annular support; 19. Lifting ear; a. Catalyst. DETAILED DESCRIPTION

[0053] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0054] It should be noted that the term "comprising" in the specification and claims of this application and the above-mentioned drawings is intended to cover non-exclusive inclusions. In this application, the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", etc. is based on the orientation or positional relationship shown in the drawings. These terms are mainly for better describing the present application and its embodiments, and are not used to limit the indicated components to have specific orientations. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to the specific circumstances.

[0055] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0056] Example 1

[0057] like Figure 1 As shown, this embodiment provides a reactor for synthesizing vinyl chloride, the reactor comprising a reactor shell;

[0058] The reactor shell includes a cylindrical body 1, an upper head 2 and a lower head 3; the upper head 2 and the lower head 3 are fixedly connected to the two ends of the body 1 respectively; the diameter of the body 1 is 4.0 mm and the wall thickness is 20 mm;

[0059] An upper top plate 4 is fixedly arranged between the cylinder 1 and the upper end cover 2, and a lower bottom plate 5 is fixedly arranged between the cylinder 1 and the lower end cover 3;

[0060] The upper top plate 4 is provided with a plurality of first communication ports; the lower bottom plate 5 is provided with a plurality of second communication ports; 2149 heat exchange tubes 6 are fixedly connected between the upper top plate 4 and the lower bottom plate 5; the central axis of the heat exchange tube 6 is parallel to the central axis of the cylinder 1; the two ends of the heat exchange tube 6 are respectively connected to the first communication port and the second communication port;

[0061] like Figure 2 and 3As shown, the heat exchange tube 6 is a hollow structure. A hollow core tube 7 with closed ends is provided in the center of each heat exchange tube 6. The core tube 7 is movably connected to the heat exchange tube 6 through a positioning plate 8. The core tube 7 and the positioning plate 8 are fixedly connected. In some embodiments, the core tube 7 and the positioning plate 8 are movably connected. Or, in some embodiments, one end of the core tube 7 is fixedly connected to the positioning plate 8, and the other end is movably connected.

[0062] In this embodiment, the areas of the upper top plate 4 and the lower bottom plate 5 are the same, which is equal to the cross-sectional area of ​​the cylinder 1 , and both the upper top plate 4 and the lower bottom plate 5 are circular structures.

[0063] like Figure 2 As shown, the length of the core tube 7 is equal to the length of the heat exchange tube 6 to enhance the structural stability of the reactor during the reaction process.

[0064] The outer diameter of the core tube 7 is smaller than the inner diameter of the heat exchange tube 6. Figure 4 As shown, Figure 2 In the partial enlarged view of A in the middle, a reaction zone is formed between the core tube 7 and the heat exchange tube 6, and the reaction zone is filled with catalyst a. The reaction zone is used to prevent a large change in the radial temperature gradient in the heat exchange tube 6, which causes non-uniform deactivation of the catalyst a in the radial plane. The catalyst a constitutes a catalyst bed in the reaction zone in each heat exchange tube 6.

[0065] In this embodiment, a detachable intercepting net with a hole structure is provided at both ends of the heat exchange tube 6. The pore size of the hole structure is smaller than the particle size of the catalyst a, so as to fix the catalyst a in the reaction zone of the heat exchange tube 6 and allow the reaction raw materials to pass through the reaction zone for sufficient reaction, thereby preventing the catalyst a from scattering outside the heat exchange tube 6 and affecting the efficiency of the catalytic reaction.

[0066] In this embodiment, the length ratio of the outer diameter of the core tube 7 to the inner diameter of the heat exchange tube 6 is 10:17.

[0067] like Figure 3 As shown, in this embodiment, three engaging pieces are provided on the positioning piece 8, and the angle between each adjacent engaging piece is 120°.

[0068] In this embodiment, the upper top plate 4 is provided with a locking groove for locking the positioning plate 8 at each of the first connecting ports, which is used to lock the locking plate of the positioning plate 8 into the locking groove, thereby fixing the core tube 7 at the center position of the heat exchange tube 6, so as to further enhance the stability of the core tube 7 in the heat exchange tube 6.

[0069] The number of the first communicating ports and the second communicating ports is equal, the shapes of the first communicating ports and the second communicating ports are both circular structures, and the areas of the first communicating ports and the second communicating ports are equal.

[0070] In this embodiment, a thermocouple is provided in each of the heat exchange tubes 6 to measure the axial temperature and radial temperature changes on the catalyst bed, so as to timely observe the changes in the catalyst bed temperature in the reaction zone.

[0071] like Figure 1 As shown, the upper sealing head 2 is also provided with a temperature measuring port 9, and the temperature measuring port 9 is used for installing and removing the thermocouple.

[0072] In this embodiment, the outer diameter of the heat exchange tube 6 is smaller than the inner diameter of the cylinder 1 , and the outer diameter of the heat exchange tube 6 is 51 mm, and the wall thickness is 3.5 mm.

[0073] In some embodiments, a plurality of the heat exchange tubes 6 are divided into a plurality of heat exchange tube groups, each of the heat exchange tube groups comprising a plurality of heat exchange tubes 6 distributed in a circular shape, and the plurality of heat exchange tube groups are distributed in the cylinder 1 from the inside to the outside with the central axis of the cylinder 1 as the center, and the spacing between each adjacent heat exchange tube 6 in the same group of the heat exchange tube groups is the same.

[0074] like Figure 1 As shown, the upper sealing head 2 is provided with a first material inlet and outlet pipe 10 , and the central axis of the first material inlet and outlet pipe 10 is parallel to the central axis of the cylinder 1 .

[0075] The lower sealing head 3 is provided with a second material inlet and outlet pipe 11 , and the central axis of the second material inlet and outlet pipe 11 is parallel to the central axis of the cylinder 1 .

[0076] In this embodiment, the first material inlet and outlet pipe 10 is a feed port, and the second material inlet and outlet pipe 11 is a discharge port; in some embodiments, when the second material inlet and outlet pipe 11 is feeding, the first material inlet and outlet pipe 10 is discharging;

[0077] That is, the reaction raw materials can be fed from the first material inlet and outlet pipe 10 and discharged from the second material inlet and outlet pipe 11; or they can be fed from the second material inlet and outlet pipe 11 and discharged from the first material inlet and outlet pipe 10; the catalyst a with higher activity in the reaction zone is fully utilized, the utilization rate of the catalyst a is improved, and the service life of the catalyst a is extended.

[0078] The reactor is also provided with a pipeline for adjusting the flow direction of reaction raw materials, and the pipeline is connected to the first material inlet and outlet pipe 10 and the second material inlet and outlet pipe 11.

[0079] like Figure 1As shown, in this embodiment, a manhole 12 is further provided on the upper head 2 to facilitate maintenance of the reactor or disassembly and installation of the core tube 7.

[0080] The cylinder 1 is provided with a refrigerant inlet 13 at one end close to the lower head 3 , and a refrigerant outlet 14 at one end close to the upper head 2 .

[0081] The cylinder 1 is also provided with an overflow device 15, which includes an overflow vertical pipe 1501 and an overflow outlet 1502 connected to one end of the overflow vertical pipe 1501, the overflow vertical pipe 1501 is located in the cylinder 1, the overflow outlet 1502 is located on the side wall of the cylinder 1, the other end of the overflow vertical pipe 1501 is an overflow inlet, the distance between the overflow inlet and the upper top plate 4 is smaller than the distance between the refrigerant outlet 14 and the upper top plate 4, and the overflow device 15 is used to maintain the liquid level of the refrigerant in the reactor.

[0082] The cylinder 1 is provided with a shell-side gas venting port 16 near the upper top plate 4 , and the cylinder 1 is provided with a shell-side waste discharge port 17 near the lower bottom plate 5 .

[0083] An annular support 18 is also fixed to the side of the cylinder 1 for fixing the reactor.

[0084] The annular support 18 , the upper head 2 , and the lower head 3 are provided with a plurality of lifting ears 19 .

[0085] Example 2

[0086] This embodiment provides a system for synthesizing vinyl chloride, which includes the reactor for synthesizing vinyl chloride in Example 1, a reaction raw material supply device, a vinyl chloride collection device, a refrigerant circulation device, and a reaction raw material gas flow regulating valve.

[0087] The refrigerant circulation device comprises a refrigerant storage device, a circulation pipeline, and a supplementary refrigerant pipeline.

[0088] A reaction raw material sampling port is also provided between the reactor and the vinyl chloride collecting device.

[0089] In the system for synthesizing vinyl chloride provided in this embodiment, the system is verified by using the method for preparing vinyl chloride using acetylene. Before the reactor is used, first fill the catalyst a, which is a mercury-free catalyst. Then open the first material inlet and outlet pipe 10 and the second material inlet and outlet pipe 11, start the refrigerant circulation device, establish the reactor refrigerant preheating cycle, and when the catalyst bed temperature reaches 100°C, switch the refrigerant preheating cycle to the normal supplementary cycle. Pass an appropriate amount of hydrogen chloride to activate the catalyst a. After the activation is completed, open the reaction raw gas flow regulating valve, and control the flow of the reaction raw materials and the pressure of the shell-side refrigerant according to the catalyst bed temperature. In this embodiment, the shell-side design pressure is 0.52MPa, and the tube-side design pressure is 0.2Mpa.

[0090] In some embodiments, the flow direction of the reaction raw materials is adjusted according to the change of the catalyst bed temperature, that is, the reaction raw materials can be fed from the first material inlet and outlet pipe 10 and discharged from the second material inlet and outlet pipe 11; or the reaction raw materials can be fed from the second material inlet and outlet pipe 11 and discharged from the first material inlet and outlet pipe 10; the catalyst a with higher activity in the reaction zone is fully utilized to improve the utilization rate of the catalyst a and extend the service life of the catalyst a.

[0091] According to the test analysis results of the outlet gas, when the raw material acetylene content collected from the reaction raw material sampling port cannot reach the process control index, the reactor is cut out of the production line and the catalyst a is replaced.

[0092] The present embodiment provides a system for synthesizing vinyl chloride, including a reactor for synthesizing vinyl chloride, a single reactor has a large production capacity, a heat exchange tube 6 loaded with catalyst a and a core tube 7 matched with the heat exchange tube 6 are concentric double-layer tubes, the resistance in the reaction is basically the same, the gas is evenly distributed, and it has the characteristics of high production intensity, high conversion rate, long equipment service life and complete utilization of catalyst a. Compared with the converter used in domestic production processes, the production capacity of a single unit is more than 1.5-2 times.

[0093] Taking the construction of a 200,000 tons / year vinyl chloride production line as an example, if a φ3200mm reactor in the prior art is used, 48 reactors are required, while the reactor in this embodiment only requires about 26 reactors of the same diameter, which greatly reduces the fixed asset investment and production and operation costs, and saves floor space. The reaction front of the catalyst bed in the reactor is not fixed. As the operation time increases, the front will move downstream in the reactor. In order to continue to use the catalyst a that has shifted, the reactor is equipped with a pipeline that can guide the feed gas to improve the utilization rate of the catalyst a and reduce the consumption of the catalyst a.

[0094] In this embodiment, a high-performance coolant with heptane as the main component is selected, which has the advantages of rapid reaction heat transfer and stable and easy control of reaction temperature compared with hot water cooling. At the same time, it also reduces the corrosion of the reactor heat exchange tube 6, avoids the agglomeration of catalyst a and equipment corrosion caused by water leakage of the heat exchange tube 6, prolongs the service life of the reactor and catalyst a, and reduces the operating cost of the reactor. The coolant can not only reduce the reaction temperature, but also increase the reaction temperature by increasing the pressure of the shell-side coolant to ensure the conversion efficiency and prolong the service life of catalyst a.

[0095] It should be understood that the present invention is not limited to what has been described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A reactor for synthesizing vinyl chloride, characterized in that: The reactor comprises a reactor shell; The reactor shell comprises a cylindrical body (1), an upper end cap (2) and a lower end cap (3); the upper end cap (2) and the lower end cap (3) are respectively fixedly connected to the two ends of the body (1); An upper top plate (4) is fixedly provided between the cylinder (1) and the upper end cover (2), and a lower bottom plate (5) is fixedly provided between the cylinder (1) and the lower end cover (3); The upper top plate (4) is provided with a plurality of first communication ports; the lower bottom plate (5) is provided with a plurality of second communication ports; a plurality of heat exchange tubes (6) are fixedly connected between the upper top plate (4) and the lower bottom plate (5); the central axis of the heat exchange tube (6) is parallel to the central axis of the cylinder (1); the two ends of the heat exchange tube (6) are respectively connected to the first communication port and the second communication port; The heat exchange tube (6) is a hollow structure. A hollow core tube (7) with closed ends is provided at the center of each heat exchange tube (6). The core tube (7) is movably connected to the heat exchange tube (6) via a positioning plate (8). The core tube (7) and the positioning plate (8) are fixedly and / or movably connected.

2. The reactor for synthesizing vinyl chloride according to claim 1, characterized in that: The length of the core tube (7) is equal to the length of the heat exchange tube (6).

3. The reactor for synthesizing vinyl chloride according to claim 2, characterized in that: The outer diameter of the core tube (7) is smaller than the inner diameter of the heat exchange tube (6), and a reaction zone is formed between the core tube (7) and the heat exchange tube (6).

4. The reactor for synthesizing vinyl chloride according to claim 3, characterized in that: The length ratio of the outer diameter of the core tube (7) to the inner diameter of the heat exchange tube (6) is (10-15):(17-60).

5. The reactor for synthesizing vinyl chloride according to claim 1, characterized in that: The positioning piece (8) is provided with three engaging pieces, and the angle between each adjacent engaging piece is 120°.

6. The reactor for synthesizing vinyl chloride according to claim 1, characterized in that: The plurality of heat exchange tubes (6) are divided into a plurality of heat exchange tube groups, each of the plurality of heat exchange tube groups comprising a plurality of heat exchange tubes (6) distributed in a circular shape, the plurality of heat exchange tube groups being centered on the central axis of the cylinder (1) and distributed from the inside to the outside within the cylinder (1), and the spacing between adjacent heat exchange tubes (6) in the same heat exchange tube group being the same.

7. The reactor for synthesizing vinyl chloride according to claim 1, characterized in that: The upper end cap (2) is provided with a first material inlet and outlet pipe (10), and the central axis of the first material inlet and outlet pipe (10) is parallel to the central axis of the cylinder (1); the lower end cap (3) is provided with a second material inlet and outlet pipe (11), and the central axis of the second material inlet and outlet pipe (11) is parallel to the central axis of the cylinder (1).

8. The reactor for synthesizing vinyl chloride according to claim 7, characterized in that: The reactor is also provided with a pipeline for adjusting the flow direction of the reaction raw materials, and the pipeline is connected to the first material inlet and outlet pipe (10) and the second material inlet and outlet pipe (11).

9. The reactor for synthesizing vinyl chloride according to claim 1, characterized in that: The cylinder (1) is provided with a refrigerant inlet (13) at one end close to the lower end cover (3), and is provided with a refrigerant outlet (14) at one end close to the upper end cover (2).

10. A system for synthesizing vinyl chloride, characterized in that: The system comprises a reactor for synthesizing vinyl chloride according to any one of claims 1 to 9, a reaction raw material supply device, a vinyl chloride collection device, a refrigerant circulation device, and a reaction raw material gas flow regulating valve.

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