Fixed bed reactor and production system

Abstract

This utility model provides a tubular fixed-bed reactor and production system, relating to the field of chemical equipment technology. The tubular fixed-bed reactor provided in this application includes: an outer cylinder with a material inlet and a material outlet; a reaction device including: a first end and a second end, the first end defining a discharge chamber and the second end defining a baffle chamber; a first reaction tube, the first inlet end of the first reaction tube extending to the outside of the discharge chamber and communicating with the material inlet, and the first outlet end of the first reaction tube communicating with the baffle chamber; a second reaction tube, the second inlet end of the second reaction tube communicating with the baffle chamber, and the second outlet end of the second reaction tube communicating with the discharge chamber, the discharge chamber also communicating with the material outlet; both the first reaction tube and the second reaction tube contain a catalyst. The tubular fixed-bed reactor of this application is beneficial for reducing axial temperature difference.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, and in particular to a tubular fixed-bed reactor and production system. Background Technology

[0002] Tubular fixed-bed reactors are core equipment widely used in the chemical industry. A tubular fixed-bed reactor consists of an outer cylinder and reaction tubes housed within the outer cylinder, each containing a catalyst. The reaction tubes are used for material flow, while a cooling liquid is introduced into the area surrounding the reaction tubes within the outer cylinder. As the material flows through the reaction tubes, it reacts under the catalytic action of the catalyst within the tubes; the reaction process is exothermic, and the heat generated by the reaction is absorbed by the cooling liquid in the outer cylinder.

[0003] In existing tubular fixed-bed reactors, each reaction tube extends axially along the outer cylinder, and the reaction tubes are parallel to each other, with the reactants flowing in the same direction in each reaction tube.

[0004] However, existing tubular fixed-bed reactors suffer from a large axial temperature difference during use in a strongly exothermic reaction environment. Utility Model Content

[0005] In view of the above problems, this utility model provides a tubular fixed-bed reactor and production system to reduce the axial temperature difference of the tubular fixed-bed reactor in a strongly exothermic reaction environment.

[0006] On one hand, the tubular fixed-bed reactor provided in this application includes: an outer cylinder having a material inlet and a material outlet; a reaction device including: a first end and a second end, the first end defining a discharge chamber and the second end defining a baffle chamber, the first end and the second end being sequentially spaced apart along the axial direction of the outer cylinder and away from the material inlet, the material outlet and the material inlet being located on the same side of the first end; a first reaction tube, the first inlet end of the first reaction tube extending to the outside of the discharge chamber and communicating with the material inlet, the first outlet end of the first reaction tube communicating with the baffle chamber; a second reaction tube, the second inlet end of the second reaction tube communicating with the baffle chamber, the second outlet end of the second reaction tube communicating with the discharge chamber, the discharge chamber also communicating with the material outlet; both the first reaction tube and the second reaction tube contain a catalyst.

[0007] In some embodiments, the first end includes: a first tube sheet and a discharge end cap, the discharge end cap being disposed on the side of the first tube sheet facing the material inlet along the axial direction of the outer cylinder, the discharge end cap and the first tube sheet together defining the discharge cavity; the second end includes: a second tube sheet and a baffle end cap, the second tube sheet being located on the side of the first tube sheet along the axial direction of the outer cylinder and away from the material inlet, the baffle end cap being located on the side of the second tube sheet opposite to the first tube sheet, the baffle end cap and the second tube sheet together defining a baffle cavity.

[0008] In some embodiments, there are multiple first reaction tubes and second reaction tubes, which are arranged alternately along the radial and / or circumferential direction of the outer cylinder.

[0009] In some embodiments, the outer cylinder includes a side wall and a bottom wall, the material inlet is located on the side wall, and the material outlet is located on the bottom wall; the first tube sheet is spaced apart from the bottom wall to form a discharge chamber, and the second tube sheet is located on the side of the first tube sheet away from the bottom wall; the discharge head includes a bottom plate and a side plate surrounding the bottom plate, the side plate is connected to the first tube sheet, and the side plate has a plurality of discharge holes spaced apart circumferentially, the discharge holes and the material outlet are both in communication with the discharge chamber.

[0010] In some embodiments, the tubular fixed-bed reactor of this application further includes: a feed pipe, the feed pipe including a pipe section and a diversion end, the diversion end being connected to the discharge end cap, the diversion end surrounding a diversion cavity, and the first inlet end of the first reaction tube being connected to the diversion cavity; one end of the pipe section being connected to the diversion end, and the other end being connected to the material inlet.

[0011] In some embodiments, the pipe section has a first end communicating with the material inlet and a second end connected to the diversion end, the opening direction of the first end being parallel to the radial direction of the outer cylinder, and the opening direction of the second end being parallel to the axial direction of the outer cylinder.

[0012] In some embodiments, the side surface of the baffle head facing the baffle cavity is formed as a spherical surface.

[0013] In some embodiments, the baffle head is provided with a first flange connection structure, and the second tube sheet is provided with a second flange connection structure, wherein the first flange connection structure and the second flange connection structure are connected by fasteners.

[0014] In some embodiments, the outer cylinder includes a bottom cylinder, an intermediate cylinder, and a top cylinder connected sequentially along its own axial direction, wherein the first tube sheet forms the bottom of the intermediate cylinder, the top end of the bottom cylinder is connected to the flange of the first tube sheet, and the top end of the intermediate cylinder is connected to the bottom flange of the top cylinder; the material inlet and the material outlet are both formed in the bottom cylinder.

[0015] In some embodiments, the intermediate cylinder is further provided with a liquid inlet and a liquid outlet, with the liquid inlet located near the first tube sheet and the liquid outlet located near the second tube sheet.

[0016] In some embodiments, the inner side of the intermediate cylinder is further provided with a plurality of baffles, which are divided into two groups and located on opposite sides of the intermediate cylinder along the radial direction. Each group includes a plurality of baffles distributed along the axial direction of the outer cylinder. The baffles of the two groups are staggered along the axial direction of the outer cylinder, and the projections of the two groups of baffles in a reference plane overlap. The reference plane is perpendicular to the axial direction of the outer cylinder. The first reaction tube and the second reaction tube both pass through the baffles.

[0017] In some embodiments, the tubular fixed-bed reactor of this application further includes: an installation tube that penetrates the outer cylinder and the baffle head, the inner side of the installation tube defining a temperature measurement channel; and a temperature measuring device adapted to be inserted into the baffle cavity via the temperature measurement channel to measure the temperature.

[0018] In some embodiments, the mounting tube includes an expansion joint located inside the outer cylinder, the expansion joint being configured to expand and contract with temperature changes.

[0019] In some embodiments, the top cylinder has an openable and closable first manhole; and / or, the bottom cylinder has an openable and closable second manhole.

[0020] On the other hand, the production system provided in this application includes the aforementioned tubular fixed-bed reactor.

[0021] The tubular fixed-bed reactor of this application contains a cooling liquid for cooling the first and second reaction tubes through a portion of the inner cavity of the outer cylinder. The material is supplied with a flow path sequentially along the material inlet, the first inlet end of the first reaction tube, the first outlet end of the first reaction tube, the baffle chamber, the second inlet end of the second reaction tube, the second outlet end of the second reaction tube, the discharge chamber, and the material outlet. This ensures that the flow directions of the material in the first and second reaction tubes are opposite. On the one hand, this helps to balance the axial temperature difference in the tubular fixed-bed reactor, reducing the axial temperature difference during operation. On the other hand, it helps to compensate for the heat in the second reaction tube with the heat generated by the first reaction tube, maintaining the temperature of the second reaction tube and thus the activity of the catalyst, thereby improving the reaction efficiency in the second reaction tube. The balanced tubular fixed-bed reactor of this application also facilitates timely cooling in the early stages of the reaction, preventing excessively high temperatures near the first inlet end of the first reaction tube. The tubular fixed-bed reactor of this application also facilitates the preheating of the portion of the first reaction tube located in the discharge chamber through the discharge chamber, thereby preheating the material and improving the reaction efficiency. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of a tubular fixed-bed reactor provided in an embodiment of this application;

[0024] Figure 2 for Figure 1 A schematic diagram showing the connection between the second end and the mounting tube in the outer cylinder;

[0025] Figure 3 for Figure 1 A schematic diagram showing the connection between the first end and the feed pipe in the outer cylinder;

[0026] Figure 4 for Figure 1 A schematic diagram showing the connection between the first reaction tube, the second reaction tube, and the discharge end cap.

[0027] Figure 5 This is a schematic diagram of the packing structure of the catalyst in the first reaction tube provided in an embodiment of this application.

[0028] Explanation of reference numerals in the attached figures:

[0029] 100-Outer cylinder; 100a-Material inlet; 100b-Material outlet; 100c-Side wall; 100d-Bottom wall; 100e-Discharge chamber; 110-Bottom cylinder; 111-Second manhole; 111a-Second manhole cover; 120-Intermediate cylinder; 121-Liquid inlet; 122-Liquid outlet; 123-Baffle plate; 130-Top cylinder; 131-First manhole; 131a-First manhole cover;

[0030] 200 - Reaction apparatus; 200a - Discharge chamber; 200b - Baffle chamber; 210 - First end; 211 - First tube sheet; 212 - Discharge end cap; 212a - Base plate; 212b - Side plate; 212c - Discharge hole; 220 - Second end; 221 - Second tube sheet; 221a - Second flange connection structure; 221b - Sealing ring; 222 - Baffle end cap; 222a - First flange connection structure; 230 - First reaction tube; 230a - First inlet end; 230b - First outlet end; 240 - Second reaction tube; 240a - Second inlet end; 240b - Second outlet end;

[0031] 300-catalyst;

[0032] 400 - Feed pipe; 410 - Pipe section; 410a - First end; 410b - Second end; 420 - Diversion end; 420a - Diversion cavity;

[0033] 500 - Installation pipe; 500a - Temperature measurement channel; 510 - Expansion joint;

[0034] 600-Temperature measuring device. Detailed Implementation

[0035] To make the above-mentioned objectives, features, and advantages of the embodiments of this application more apparent and understandable, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0036] Tubular fixed-bed reactors are core equipment widely used in the chemical industry. A tubular fixed-bed reactor consists of an outer cylinder and reaction tubes housed within the outer cylinder, each containing a catalyst. The reaction tubes are used for material flow, while a cooling liquid is introduced into the area surrounding the reaction tubes within the outer cylinder. As the material flows through the reaction tubes, it reacts under the catalytic action of the catalyst within the tubes; the reaction process is exothermic, and the heat generated by the reaction is absorbed by the cooling liquid in the outer cylinder.

[0037] In existing tubular fixed-bed reactors, each reaction tube extends axially along the outer cylinder, and the reaction tubes are parallel to each other, with the reactants flowing in the same direction in each reaction tube.

[0038] However, existing tubular fixed-bed reactors suffer from significant axial temperature differences during operation in highly exothermic reaction environments. For example, in highly exothermic reactions (such as ammonia synthesis, methanol synthesis, and Fischer-Tropsch synthesis), the heat generated in the initial stage of the reaction is far greater than that generated in the later stage. This objective situation leads to the problem of large axial temperature differences in existing tubular fixed-bed reactors during operation.

[0039] Furthermore, on the one hand, the initial stage of the reaction releases a large amount of heat. If the heat cannot be dissipated in time, it will lead to excessively high local temperatures in the reaction tube or even the outer cylinder, which can easily cause catalyst sintering or deactivation. On the other hand, when the axial temperature difference is too large, axial thermal stress is easily generated between the reaction tube and the outer cylinder due to the temperature difference, which can easily lead to deformation, leakage, or even rupture of the tubular fixed bed reactor.

[0040] To reduce the axial temperature difference in a tubular fixed-bed reactor during operation, this application provides a tubular fixed-bed reactor and a production system. The tubular fixed-bed reactor of this application contains a cooling liquid for cooling the first and second reaction tubes through a portion of the inner cavity of the outer cylinder. The material is supplied with a flow path sequentially along the material inlet, the first inlet end of the first reaction tube, the first outlet end of the first reaction tube, the baffle chamber, the second inlet end of the second reaction tube, the second outlet end of the second reaction tube, the discharge chamber, and the material outlet, through the material inlet, the first reaction tube, the first outlet end of the first reaction tube, the baffle chamber, the second inlet end of the second reaction tube, the second outlet end of the second reaction tube, the discharge chamber, and the material outlet. This ensures that the flow directions of the material in the first and second reaction tubes are opposite. On the one hand, this helps to balance the axial temperature difference in the tubular fixed-bed reactor, thus reducing the axial temperature difference during operation. On the other hand, it helps to use the heat generated by the first reaction tube to compensate for the heat in the second reaction tube, maintaining the temperature of the second reaction tube and thus maintaining the activity of the catalyst in the second reaction tube, thereby improving the reaction efficiency in the second reaction tube. The tubular fixed-bed reactor of this application also facilitates timely cooling during the early stages of the reaction, preventing excessively high temperatures near the first inlet end of the first reaction tube. Furthermore, the tubular fixed-bed reactor of this application, through its discharge chamber, facilitates preheating of the portion of the first reaction tube located within the discharge chamber, thereby preheating the material and improving reaction efficiency.

[0041] Reference Figure 1 As shown, the tubular fixed-bed reactor of this application includes an outer cylinder 100 and a reaction device 200.

[0042] The outer cylinder 100 has a material inlet 100a and a material outlet 100b. It is understood that the material inlet 100a is used to introduce materials before the reaction, and the material outlet 100b is used to discharge materials after the reaction. For example, the outer cylinder 100 can be a single-section structure; or, the outer cylinder 100 can be a multi-section spliced ​​structure. It should be noted that the specific shape of the outer cylinder can be flexibly selected and set according to actual needs.

[0043] The reaction apparatus 200 includes a first end 210, a second end 220, a first reaction tube 230, and a second reaction tube 240. The first end 210 defines a discharge chamber 200a, which, by example, may be cuboid; or cylindrical; or partially spherical. The second end 220 defines a baffle chamber 200b, which, by example, may be cuboid; or cylindrical; or partially spherical. The first end 210 and the second end 220 are sequentially spaced apart along the axial direction of the outer cylinder 100 and away from the material inlet 100a, with the material outlet 100b and the material inlet 100a located on the same side of the first end 210.

[0044] Reference Figure 1 , Figure 3 and Figure 4 As shown, the first inlet end 230a of the first reaction tube 230 extends to the outside of the discharge chamber 200a. The first inlet end 230a of the first reaction tube 230 is connected to the material inlet 100a, so as to introduce the material introduced through the material inlet 100a into the first reaction tube outside the discharge chamber 200a.

[0045] Reference Figure 1 and Figure 2 As shown, the first outlet end 230b of the first reaction tube 230 is connected to the baffle chamber 200b. It can be understood that the reactants in each first reaction tube 230 flow out through the corresponding first outlet end 230b and into the baffle chamber 200b; the baffle chamber 200b is used to collect the reactants flowing out from the first outlet ends 230b of each first reaction tube 230. Under the collecting effect of the baffle chamber 200b, the heat and material components of the reactants can be mixed uniformly by the baffle chamber 200b.

[0046] The second inlet end 240a of the second reaction tube 240 is connected to the baffle chamber 200b. Understandably, the baffle chamber 200b is used to deflect the collected reactants through the second inlet end 240a into each of the second reaction tubes 240, so as to form a flow in the opposite direction to the material in the first reaction 230.

[0047] Reference Figure 1 , Figure 3 and Figure 3 As shown, the second outlet end 240b of the second reaction tube 240 is connected to the discharge chamber 200a. On the one hand, the discharge chamber 200a is used to buffer the reacted material; on the other hand, the reacted material has a certain amount of heat, which can be used to heat the portion of the first reaction tube 230 located in the discharge chamber 200a, thereby preheating the material before the reaction and improving the material reaction efficiency. The discharge chamber 200a is also connected to the material outlet 100b, which is used to discharge the reacted material buffered in the discharge chamber 200a.

[0048] Reference Figure 1 and Figure 5 As shown, both the first reaction tube 230 and the second reaction tube 240 are equipped with catalysts 300. It should be noted that the type of catalyst 300 can be flexibly selected and set according to actual needs; the specific arrangement of the catalyst 300 in the first reaction tube 230 and the second reaction tube 240 can also be flexibly selected and set according to actual needs.

[0049] For example, catalyst 300 is loaded into a first reaction tube 230 and a second reaction tube 240; specifically, taking the first reaction tube 230 as an example, both the first inlet end 230a and the first outlet end 230b of the first reaction tube 230 are fixedly provided with wire mesh 231, and the section inside the first reaction tube 230 near the wire mesh 231 is filled with ceramic balls to form a ceramic ball loading section 232. Solid catalyst 300 is loaded between the two ceramic ball loading sections 232. It can be understood that the catalyst 300 is maintained in the first reaction tube 230 by the ceramic ball loading section 232 and the wire mesh 231.

[0050] Furthermore, exemplary, springs may also be provided in the first reaction tube 230 and the second reaction tube 240. The springs, as compressible fillers, apply a continuous and gentle axial pressure to the catalyst 300, thereby: compressing the catalyst and preventing catalyst particles from moving in the gas flow; eliminating top voids and forcing the gas flow to pass evenly through the entire catalyst 300; and buffering thermal expansion, as the springs can compensate for the thermal expansion and contraction of the catalyst reaction tubes (first reaction tube 230 or second reaction tube 240) during heating and cooling processes, preventing the reaction tubes from cracking or the catalyst from being crushed.

[0051] Alternatively, by way of example, the catalyst 300 may also be disposed in the first reaction tube 230 and the second reaction tube 240 by coating.

[0052] Reference Figure 1 and Figure 5As shown, the tubular fixed-bed reactor of this application contains a portion of the inner cavity of the outer cylinder 100 containing a coolant for cooling the first reaction tube 230 and the second reaction tube 240; the material is supplied sequentially along the material inlet 100a, the first inlet end 230a of the first reaction tube 230, the first outlet end 230b of the first reaction tube 230, the baffle chamber 200b, the second inlet end 240a of the second reaction tube 240, and the material outlet 100b. The flow paths of the second outlet 240b, the discharge chamber 200a, and the material outlet 100b are arranged so that the flow directions of the material in the first reaction tube 230 and the second reaction tube 240 are opposite. On the one hand, this helps to balance the axial temperature difference in the tubular fixed-bed reactor, reducing the axial temperature difference during operation. On the other hand, it helps to compensate for the heat in the second reaction tube 240 with the heat generated by the first reaction tube 230, maintaining the temperature of the second reaction tube and thus the activity of the catalyst, thereby improving the reaction efficiency. The tubular fixed-bed reactor of this application also facilitates timely cooling in the early stages of the reaction, preventing excessively high temperatures near the first inlet end of the first reaction tube. The discharge chamber 200a of the tubular fixed-bed reactor of this application also facilitates preheating of the portion of the first reaction tube 230 located in the discharge chamber 200a, thereby preheating the material and improving reaction efficiency.

[0053] Reference Figure 1 and Figure 5 As shown, it should be noted that because the heat generated in the early stage of the reaction is much greater than that generated in the later stage, the heat distribution in the first reaction tube 230 decreases from the first inlet end 230a to the first outlet end 230b. Similarly, the heat distribution in the second reaction tube 240 decreases from the second inlet end 240a to the second outlet end 240b. The heat generated in the first reaction tube 230 is greater than that generated in the second reaction tube 240. For these reasons, the opposite flow directions of the materials in the first reaction tube 230 and the second reaction tube 240 help balance the heat release difference between the early and later stages of the reaction, thereby reducing the axial temperature difference during the operation of the tubular fixed-bed reactor.

[0054] In some implementations, refer to Figure 1 , Figure 2 and Figure 4As shown, the first end 210 includes a first tube sheet 211 and a discharge end cap 212. The discharge end cap 212 is located on the side of the first tube sheet 211 facing the material inlet 100a along the axial direction of the outer cylinder 100, and the discharge end cap 212 and the first tube sheet 211 together define a discharge chamber 200a. It can be understood that by having the discharge end cap 212 and the first tube sheet 211 jointly define the discharge chamber 200a, it is beneficial to collect and deflect the material at the end of the first tube sheet 211, which facilitates efficient collection and deflection, and also benefits the uniformity of heat and composition of the collected airflow. For example, the discharge end cap 212 and the first tube sheet 211 can be fixedly connected by welding; or, the discharge end cap 212 and the first tube sheet 211 can be detachably connected by flanges and fasteners. For example, a channel or hole may be provided on the discharge end cap 212 to connect the discharge chamber 200a and the material outlet 100b.

[0055] For example, the first tube sheet 211 has holes for a first reaction tube 230 to pass through; the first tube sheet 211 also has holes for a second reaction tube 240 to pass through. The first reaction tube 230 and the second reaction tube 240 are respectively passed through corresponding holes on the first tube sheet 211. At least a portion of the section of the first reaction tube 230 that passes through the first tube sheet 211 abuts against the inner wall of the corresponding hole, and the first reaction tube 230 and the corresponding hole are fixed together by reinforcing weld. At least a portion of the section of the second reaction tube 240 that passes through the first tube sheet 211 abuts against the inner wall of the corresponding hole, and the second reaction tube 240 and the corresponding hole are fixed together by reinforcing weld.

[0056] Reference Figure 1 and Figure 2 As shown, the second end 220 includes a second tube sheet 221 and a baffle head 222. The second tube sheet 221 is located on the side of the first tube sheet 211 along the axial direction of the outer cylinder 100 and away from the material inlet 100a. The baffle head 222 is located on the side of the second tube sheet 221 opposite to the first tube sheet 211. The baffle head 222 and the second tube sheet 221 together define a baffle cavity 200b. Exemplarily, the second tube sheet 221 and the baffle head 222 can be fixedly connected by welding; or, the second tube sheet 221 and the baffle head 222 can be detachably connected by flanges and fasteners.

[0057] For example, the second tube sheet 221 has holes for passing through the first reaction tube 230 and holes for passing through the second reaction tube 240. The first reaction tube 230 and the second reaction tube 240 are respectively passed through the corresponding holes on the second tube sheet 221. At least a portion of the section of the first reaction tube 230 passing through the second tube sheet 221 abuts against the inner wall of the corresponding hole, and the second reaction tube 240 and the corresponding hole are fixed together by reinforcing weld. At least a portion of the section of the second reaction tube 240 passing through the second tube sheet 221 abuts against the inner wall of the corresponding hole, and the second reaction tube 240 and the corresponding hole are fixed together by reinforcing weld.

[0058] Reference Figure 1 and Figure 4 As shown, in some embodiments, there are multiple first reaction tubes 230 and second reaction tubes 240. The first reaction tubes 230 and second reaction tubes 240 are staggered along the radial and / or circumferential direction of the outer cylinder 100. It should be noted that "the first reaction tubes 230 and second reaction tubes 240 are staggered along the radial and / or circumferential direction of the outer cylinder 100" means that each first reaction tube 230 is surrounded by other first reaction tubes 230, and each second reaction tube 240 is surrounded by other first reaction tubes 230. It should be noted that, since the heat generated by the first reaction tube 230 is higher than that generated by the second reaction tube 240 during operation, this arrangement of the first reaction tubes 230 and second reaction tubes 240 helps to improve the uniformity of heat distribution in the axial and radial directions of the outer cylinder 100 within the coolant-filled inner cavity, thus reducing both the axial and radial temperature differences.

[0059] Reference Figure 4 As shown, exemplarily, the ratio of the number of the first reaction tube 230 and the second reaction tube 240 is 0.8 to 1.2, for example, 0.8, 0.96, 1, 1.04, or 1.2. In the most ideal embodiment, the ratio of the number of the first reaction tube 230 and the second reaction tube 240 is 1.

[0060] Reference Figure 1 and Figure 4As shown, exemplarily, the inner diameters of the first reaction tube 230 and the second reaction tube 240 are the same, and the wall thicknesses of the first reaction tube 230 and the second reaction tube 240 are the same. Alternatively, exemplarily, the inner diameters of the first reaction tube 230 and the second reaction tube 240 may have a small difference; the wall thicknesses of the first reaction tube 230 and the second reaction tube 240 may have a small difference; specifically, the inner diameter of the first reaction tube 230 may be slightly smaller than the inner diameter of the second reaction tube 240, in order to increase the flow rate of the reactants in the first reaction tube 230, which helps to reduce the heat generated in the first reaction tube 230 during the reaction process to a certain extent, and further improves the axial uniformity of heat in the inner cavity of the outer cylinder 100 used to contain the coolant.

[0061] Reference Figure 1 , Figure 3 and Figure 4 As shown, in some embodiments, the outer cylinder 100 includes a side wall 100c and a bottom wall 100d, with a material inlet 100a disposed on the side wall 100c and a material outlet 100b disposed on the bottom wall 100d. Exemplarily, the side wall 100c may be cylindrical, and the bottom wall 100d may be approximately spherical, with a lower center and higher edges. A first tube plate 211 is spaced from the bottom wall 100d to form a discharge chamber 100e, and a second tube plate 221 is located on the side of the first tube plate 211 away from the bottom wall 100d.

[0062] The discharge end cap 212 includes a base plate 212a and a side plate 212b surrounding the base plate 212a. Exemplarily, the base plate 212a and the side plate 212b can be connected by welding. The side plate 212b is connected to the first tube sheet 211. Exemplarily, the side plate 212b and the first tube sheet 211 can be connected by welding.

[0063] For example, the base plate 212a is provided with holes for the first reaction tube 230 to pass through. The first reaction tube 230 is passed through the corresponding holes and fixed in the corresponding holes by welding.

[0064] The side plate 212b has multiple discharge holes 212c spaced out circumferentially. Both the discharge holes 212c and the material outlet 100b are connected to the discharge chamber 100e. Understandably, the reacted material is collected and buffered in the discharge chamber 200a. The material flows from the discharge chamber 200a into the discharge chamber 100e through the discharge holes 212c. On the one hand, the discharge chamber 100e buffers the material; on the other hand, since the reacted material has a certain amount of heat, the material buffered in the discharge chamber 100e can store heat at the bottom of the cylinder 100, which helps maintain the temperature around the bottom of the first tube sheet 211 and is beneficial for energy saving.

[0065] Reference Figure 3As shown, the tubular fixed-bed reactor of this application further includes a feed pipe 400, which includes a pipe section 410 and a branch end 420. The branch end 420 is connected to the discharge end 212. For example, the branch end 420 and the discharge end 212 can be connected by welding; or, the branch end 420 and the discharge end 212 can be detachably connected by flanges and fasteners.

[0066] The diversion end 420 encloses a diversion cavity 420a, and the first inlet end 230a of the first reaction tube 230 is connected to the diversion cavity 420a. It should be noted that the reactants are gaseous, and the diversion end 420 is used to distribute the introduced reactants so that they flow evenly into the first reaction tube 230. For example, the diversion cavity 420a is funnel-shaped, with its larger opening facing the first reaction tube 230. One end of the pipe section 410 is connected to the diversion end 420, and the other end of the pipe section 410 is connected to the material inlet 100a, so that the material is guided from the material inlet 100a to the diversion cavity 420a through the pipe section 410.

[0067] Reference Figure 1 and Figure 3 As shown, it should be noted that, on the one hand, the feed pipe 400 is used to uniformly distribute and guide the reactants to each of the first reaction tubes 230. On the other hand, the feed pipe 400 can also absorb the heat of the reacted material located in the discharge chamber 100e, so as to preheat the material flowing through the feed pipe 400 through this heat, which is beneficial to improving reaction efficiency and saving energy.

[0068] Reference Figure 3 As shown, in some embodiments, the pipe section 410 has a first end 410a communicating with the material inlet 100a and a second end 410b connected to the diversion end 420. The opening direction of the first end 410a is parallel to the radial direction of the outer cylinder 100, and the opening direction of the second end 410b is parallel to the axial direction of the outer cylinder 100. The first end 410a and the second end 410b facilitate the connection of the pipe section 410. For example, the material inlet 100a and the first end 410a can be welded together; or, the material inlet 100a and the first end 410a can be detachably connected by bolts. For example, the diversion end 420 and the second end 410b can be welded together; or, the diversion end 420 and the second end 410b can be detachably connected by flanges and fasteners.

[0069] Reference Figure 1 and Figure 2As shown. In some embodiments, the surface of the baffle head 222 facing the baffle cavity 200b is formed as a spherical surface. It should be noted that this spherical surface facilitates uniform mixing of the gas streams flowing out of each of the first reaction tubes 230, which is beneficial for both uniform mixing of components and uniform mixing of heat. Furthermore, this spherical surface helps to reduce the vertical impact on the baffle head 222, thereby reducing noise. For example, the baffle head 222 is a plate, and the spherical surface is formed by bending the plate.

[0070] Reference Figure 1 and Figure 2 As shown, in some embodiments, the baffle head 222 is provided with a first flange connection structure 222a, and the second tube sheet 221 is provided with a second flange connection structure 221a. The first flange connection structure 222a and the second flange connection structure 221a are connected by fasteners. It is understood that the first flange connection structure 222a, the second flange connection structure 221a, and the fasteners facilitate the disassembly of the baffle head 222 from the second tube sheet 221, thereby facilitating equipment maintenance.

[0071] Further, exemplarily, the second flange connection structure 221a is disposed within the outer cylinder 100. Grooves are provided on the circumferential side of the second flange connection structure 221a and on the inner walls of the outer cylinder 100 facing the second flange connection structure 221a circumferentially. A sealing ring 221b is provided between the groove of the second flange connection structure 221a and the groove on the inner wall of the outer cylinder 100, so that the second flange connection structure 221a can be buoyantly connected to the outer cylinder 100 through the groove and the sealing ring, thereby allowing the second tube sheet 221 to be buoyantly connected to the outer cylinder 100.

[0072] For example, when the second tube sheet 221 is floatingly connected to the outer cylinder 100, the baffle head 222 can make the second tube sheet 221 float along its axial direction in the outer cylinder 100.

[0073] Reference Figures 1 to 4 As shown, in some embodiments, the outer cylinder 100 includes a bottom cylinder 110, an intermediate cylinder 120, and a top cylinder 130 connected sequentially along its axial direction. A first tube sheet 211 forms the bottom of the intermediate cylinder 120. The top end of the bottom cylinder 110 is flanged to the first tube sheet 211; exemplarily, this flange connection can be detachable via bolts for easy disassembly and maintenance; a gasket is placed between the two flanges to enhance sealing. The top end of the intermediate cylinder 120 is flanged to the bottom end of the top cylinder 130; exemplarily, this flange connection can be detachable via bolts for easy maintenance; a gasket can be placed between the two flanges to enhance sealing. A material inlet 100a and a material outlet 100b are both formed in the bottom cylinder 110. It is understood that this structure of the outer cylinder 100 facilitates manufacturing and processing.

[0074] Reference Figure 1 and Figure 3 As shown, in some embodiments, the intermediate cylinder 120 is further provided with an inlet 121 and an outlet 122, with the inlet 121 located near the first tube sheet 211 and the outlet 122 located near the second tube sheet 221. It should be noted that the inlet 121 is used to introduce coolant into the intermediate cylinder 120; the outlet 122 is used to discharge coolant from the intermediate cylinder 120. When the tubular fixed bed reactor proposed in this application is in use, the outer cylinder 100 is axially arranged in the vertical direction. The positions of the inlet 121, outlet 122, and outlet ensure that the coolant flows from bottom to top in the intermediate cylinder 120. On the one hand, this facilitates efficient cooling of the first inlet end 230a of the first reaction tube 230, preventing the temperature of the first inlet end 230a of the first reaction tube 230 from becoming too high. On the other hand, after absorbing heat, the coolant will form a convection phenomenon in the intermediate cylinder 120, which further promotes the uniformity of temperature in the intermediate cylinder 120 along the axial direction.

[0075] Reference Figure 1 As shown, in some embodiments, the inner side of the intermediate cylinder 120 is further provided with a plurality of baffles 123. For example, the baffles 123 are connected to the inner wall of the intermediate cylinder 120 by welding. The plurality of baffles 123 are divided into two groups, which are located on opposite sides of the intermediate cylinder 120 in the radial direction. Each group includes a plurality of baffles 123 distributed along the axial direction of the outer cylinder 100. The baffles 123 of the two groups are staggered along the axial direction of the outer cylinder 100, and the projections of the two groups of baffles 123 in the reference plane overlap. The reference plane is perpendicular to the axial direction of the outer cylinder 100.

[0076] Both the first reaction tube 230 and the second reaction tube 240 pass through the baffle plate 123. Exemplarily, the baffle plate 123 has holes for the first reaction tube 230 to pass through, and the first reaction tube 230 can be fixed in the corresponding hole by welding, forming a seal between the first reaction tube 230 and the corresponding hole. Exemplarily, the baffle plate 123 also has holes for the second reaction tube 240 to pass through, and the second reaction tube 240 can be fixed in the corresponding hole by welding, forming a seal between the second reaction tube 240 and the corresponding hole.

[0077] Understandably, by using multiple baffles 123 to create flow barriers for the coolant flowing in the intermediate cylinder 120, the flow path of the coolant is increased, thereby improving the heat transfer time between the first reaction tube 230 and the coolant, and also improving the cooling effect on both the first and second reaction tubes 240. Furthermore, the flow barriers 123 also help to improve the radial heat uniformity within the intermediate cylinder 120, reducing the radial temperature difference.

[0078] Reference Figure 1 and Figure 2 As shown, the tubular fixed-bed reactor of this application also includes an installation tube 500 and a temperature measuring device 600. The installation tube 500 penetrates the outer cylinder 100 and the baffle head 222, and the inner side of the installation tube 500 defines a temperature measuring channel 500a. Exemplarily, the outer cylinder 100 has a channel for inserting the installation tube 500, which is inserted into the channel, and the outer periphery of the installation tube 500 is welded to the channel to form a seal between the outer side of the installation tube 500 and the channel. Exemplarily, the baffle head 222 has a channel for inserting the installation tube 500, which is inserted into the channel, and the outer periphery of the installation tube 500 is welded to the channel to form a seal between the outer side of the installation tube 500 and the channel.

[0079] Temperature measuring device 600 is adapted to be inserted into baffle chamber 200b via temperature measuring channel 500a for temperature measurement. For example, temperature measuring device 600 may be a resistance temperature detector (RTD). For example, temperature measuring device 600 may be a thermocouple. The installation tube 500 and temperature measuring device 600 facilitate temperature detection of the material located in baffle chamber 200b.

[0080] For example, the number of mounting tubes 500 in the tubular fixed-bed reactor of this application can be one, two, or more. When there are two or more mounting tubes 500, a temperature measuring device 600 can be installed in each mounting tube 500. It is understood that having two or more mounting tubes 500 facilitates multi-point temperature measurement.

[0081] Reference Figure 1 and Figure 2As shown, in some embodiments, the mounting tube 500 includes an expansion joint 510 located inside the outer cylinder 100, the expansion joint 510 being configured to expand and contract with temperature changes. It should be noted that the expansion joint 510 is a pre-existing component, having a first end and a second end, the distance between which can vary. The mounting tube 500 includes a first sub-segment and a second sub-segment, the first sub-segment being fixed to the outer cylinder 100, and the second sub-segment being fixed to the baffle head 222. The lower end of the first sub-segment is connected to the first end of the expansion joint 510, and the upper end of the second sub-segment is connected to the second end of the expansion joint 510.

[0082] Understandably, when the second tube sheet 221 floats up and down in the outer cylinder 100, the mounting tube 500 can extend and retract through the expansion joint 510 to accommodate the floating action of the second tube sheet 221.

[0083] Reference Figure 1 As shown, in some embodiments, the top cylinder 130 is provided with an openable and closable first manhole 131. It is understood that a first manhole cover 131a can be provided on the first manhole 131 for opening and closing the first manhole 131. It is understood that maintenance personnel can enter the outer cylinder 100 through the opened first manhole 131 to perform maintenance on the interior of the tubular fixed-bed reactor of this application.

[0084] Reference Figure 1 As shown, in some embodiments, a closable second manhole 111 is provided on the bottom cylinder 110. It is understood that a second manhole cover 111a can be provided on the second manhole 111 for opening and closing the second manhole 111. It is understood that maintenance personnel can enter the outer cylinder 100 through the opened second manhole 111 to perform maintenance on the interior of the tubular fixed-bed reactor of this application.

[0085] Furthermore, the production system provided in this application includes the aforementioned tubular fixed-bed reactor.

[0086] For example, the production system of this application can be a production system for polymerization reactions, such as a production system for synthesizing polyethylene; or a production system for synthesizing polypropylene. Alternatively, the production system of this application can be a production system for oxidation reactions, such as a production system for oxidizing ethylene to produce ethylene oxide; or a production system for oxidizing propylene to produce acrylic acid. Alternatively, the production system of this application can be a production system for hydrogenation reactions, such as a production system for hydrogenating benzene to produce cyclohexane. These production systems share the characteristic of being catalytic reactions, and the reaction process is strongly exothermic. Alternatively, the production system of this application can be other catalytically reacted production systems where the reaction process is strongly exothermic.

[0087] Understandably, the production system provided in this application, by setting up the tubular fixed-bed reactor provided in this application, facilitates timely cooling of the highly exothermic reaction and avoids excessively high local temperatures. Simultaneously, the axial temperature of the tubular fixed-bed reactor is uniform during the reaction process.

[0088] The various embodiments or implementation methods described in this specification are presented in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0089] It should be noted that the embodiments referred to in the specification, such as "one embodiment," "embodiment," "exemplary embodiment," and "some embodiments," may include specific features, structures, or characteristics, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0090] Generally speaking, terms should be understood at least in part by their use in context. For example, at least in part by context, the term "one or more" as used in the text can be used to describe any feature, structure, or characteristic of the singular meaning, or a combination of features, structures, or characteristics of the plural meaning. Similarly, at least in part by context, terms such as "a" or "the" can also be understood to convey either singular or plural usage.

[0091] It should be readily understood that the terms “on,” “above,” and “on top of” in this disclosure should be interpreted in the broadest possible sense, such that “on” means not only “directly on something” but also “on something” with an intermediate feature or layer therebetween, and that “above” or “on top of” means not only “on top of something” but also “on top of something” without an intermediate feature or layer therebetween (i.e., directly on something).

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A tubular fixed-bed reactor, characterized in that, include: The outer cylinder (100) has a material inlet (100a) and a material outlet (100b); The reaction apparatus (200) includes: A first end (210) and a second end (220), the first end (210) defining a discharge chamber (200a) and the second end (220) defining a baffle chamber (200b), the first end (210) and the second end (220) being sequentially spaced apart along the axial direction of the outer cylinder (100) and away from the material inlet (100a), the material outlet (100b) and the material inlet (100a) being located on the same side of the first end (210); The first reaction tube (230) has a first inlet end (230a) extending to the outside of the discharge chamber (200a) and connected to the material inlet (100a), and a first outlet end (230b) connected to the baffle chamber (200b). The second reaction tube (240) has a second inlet end (240a) connected to the baffle chamber (200b) and a second outlet end (240b) connected to the discharge chamber (200a). The discharge chamber (200a) is also connected to the material outlet (100b). Both the first reaction tube (230) and the second reaction tube (240) are equipped with catalysts (300).

2. The tubular fixed-bed reactor according to claim 1, characterized in that, The first end (210) includes: a first tube sheet (211) and a discharge end cap (212). The discharge end cap (212) is disposed on the side of the first tube sheet (211) facing the material inlet (100a) along the axial direction of the outer cylinder (100). The discharge end cap (212) and the first tube sheet (211) together define the discharge cavity (200a). The second end (220) includes a second tube sheet (221) and a baffle head (222). The second tube sheet (221) is located on the side of the first tube sheet (211) along the axial direction of the outer cylinder (100) and away from the material inlet (100a). The baffle head (222) is located on the side of the second tube sheet (221) opposite to the first tube sheet (211). The baffle head (222) and the second tube sheet (221) together define a baffle cavity (200b).

3. The tubular fixed-bed reactor according to claim 2, characterized in that, There are multiple first reaction tubes (230) and second reaction tubes (240), and the first reaction tubes (230) and second reaction tubes (240) are arranged alternately in the radial and / or circumferential directions along the outer cylinder (100).

4. The tubular fixed-bed reactor according to claim 2, characterized in that, The outer cylinder (100) includes a side wall (100c) and a bottom wall (100d), the material inlet (100a) is located on the side wall (100c), and the material outlet (100b) is located on the bottom wall (100d); The first tube sheet (211) is spaced from the bottom wall (100d) to form a discharge chamber (100e), and the second tube sheet (221) is located on the side of the first tube sheet (211) away from the bottom wall (100d); The discharge end cap (212) includes a base plate (212a) and a side plate (212b) surrounding the base plate (212a). The side plate (212b) is connected to the first tube plate (211). The side plate (212b) has a plurality of discharge holes (212c) spaced apart along the circumference. The discharge holes (212c) and the material outlet (100b) are both connected to the discharge chamber (100e).

5. The tubular fixed-bed reactor according to claim 4, characterized in that, Also includes: The feed pipe (400) includes a pipe section (410) and a branch end (420). The diversion end (420) is connected to the discharge end (212), and the diversion end (420) surrounds the diversion cavity (420a). The first inlet end (230a) of the first reaction tube (230) is connected to the diversion cavity (420a). One end of the pipe section (410) is connected to the diversion end (420), and the other end is connected to the material inlet (100a).

6. The tubular fixed-bed reactor according to claim 5, characterized in that, The pipe section (410) has a first end (410a) communicating with the material inlet (100a) and a second end (410b) communicating with the diversion end (420). The opening direction of the first end (410a) is parallel to the radial direction of the outer cylinder (100), and the opening direction of the second end (410b) is parallel to the axial direction of the outer cylinder (100).

7. The tubular fixed-bed reactor according to claim 2, characterized in that, The side surface of the baffle head (222) facing the baffle cavity (200b) is formed as a spherical surface.

8. The tubular fixed-bed reactor according to claim 2, characterized in that, The baffle head (222) is provided with a first flange connection structure (222a), and the second tube sheet (221) is provided with a second flange connection structure (221a). The first flange connection structure (222a) and the second flange connection structure (221a) are connected by fasteners.

9. The tubular fixed-bed reactor according to claim 2, characterized in that, The outer cylinder (100) includes a bottom cylinder (110), an intermediate cylinder (120), and a top cylinder (130) connected sequentially along its own axial direction. The first tube sheet (211) forms the bottom of the intermediate cylinder (120), the top of the bottom cylinder (110) is connected to the flange of the first tube sheet (211), and the top of the intermediate cylinder (120) is connected to the bottom flange of the top cylinder (130). The material inlet (100a) and the material outlet (100b) are both formed in the bottom cylinder (110).

10. The tubular fixed-bed reactor according to claim 9, characterized in that, The intermediate cylinder (120) is also provided with a liquid inlet (121) and a liquid outlet (122). The liquid inlet (121) is located near the first tube sheet (211), and the liquid outlet (122) is located near the second tube sheet (221).

11. The tubular fixed-bed reactor according to claim 10, characterized in that, The inner side of the intermediate cylinder (120) is also provided with a plurality of baffles (123). The plurality of baffles (123) are divided into two groups, which are located on opposite sides of the intermediate cylinder (120) in the radial direction. Each group includes a plurality of baffles (123) distributed along the axial direction of the outer cylinder (100). The two sets of baffles (123) are staggered along the axial direction of the outer cylinder (100), and the projections of the two sets of baffles (123) in the reference plane overlap, the reference plane being perpendicular to the axial direction of the outer cylinder (100); Both the first reaction tube (230) and the second reaction tube (240) pass through the baffle plate (123).

12. The tubular fixed-bed reactor according to claim 2, characterized in that, Also includes: The mounting tube (500) passes through the outer cylinder (100) and the baffle head (222), and the inner side of the mounting tube (500) defines a temperature measurement channel (500a); Temperature measuring device (600), the temperature measuring device (600) is adapted to be inserted into the baffle cavity (200b) via the temperature measuring channel (500a) to measure temperature.

13. The tubular fixed-bed reactor according to claim 12, characterized in that, The mounting tube (500) includes an expansion joint (510) located inside the outer cylinder (100), the expansion joint (510) being configured to expand and contract with temperature changes.

14. The tubular fixed-bed reactor according to claim 9, characterized in that, The top cylinder (130) is provided with an openable and closable first manhole (131); and / or, The bottom cylinder (110) is provided with an openable and closable second manhole (111).

15. A production system, characterized in that, include: The tubular fixed-bed reactor according to any one of claims 1-14.

Images