Multi-section tubular reactor

Abstract

The utility model provides a multi-section tubular reactor and belongs to the technical field of tubular reactors. The multi-section tubular reactor solves the problem that the material temperature and the like of the existing multi-section tubular reactor are difficult to control. The multi-section tubular reactor comprises a first reaction tube with a feeding hole in the bottom and a second reaction tube with a discharging hole in the top, a plurality of first heat exchange tubes are arranged in the first reaction tube at intervals, and a first heat exchange cavity is formed between the inner side wall of the first reaction tube and the outer side walls of all the first heat exchange tubes; a plurality of second heat exchange pipes are arranged in the second reaction pipe at intervals, a second heat exchange cavity is formed between the inner side wall of the second reaction pipe and the outer side walls of all the second heat exchange pipes, a transition pipe is arranged between the first reaction pipe and the second reaction pipe, and a third heat exchange pipe arranged in a snake shape is arranged in the transition pipe; the third heat exchange pipes are integrally arranged in the radial direction of the transition pipe. The multi-section tubular reactor has the advantages that the temperature of materials can be accurately controlled, and the product quality is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of tubular reactors and relates to a multi-section tubular reactor. Background Art

[0002] The multi-stage tubular reactor is a continuously operated reaction equipment widely used in the fields of chemical industry, petroleum refining and chemical synthesis. Its design is based on the single-stage tubular reactor, but it has been optimized and upgraded according to process requirements, dividing the entire tube bundle into two or more independent reaction sections.

[0003] In a multi-stage tubular reactor, each stage can have different temperature control, pressure conditions, catalyst type or reaction time to adapt to the multi-step process of complex chemical reactions. The material first enters the first stage, where it undergoes a preliminary reaction; then it enters the next stage through an internal redistribution device to continue the subsequent reaction steps. More precise control of the reaction process helps to improve conversion rate, selectivity and product quality.

[0004] In addition, since many chemical reactions are accompanied by strong exothermic or endothermic effects, the multi-stage design can more effectively manage these heat changes. Each reaction stage can accurately control the reaction temperature through the heat exchange medium between the shell and tube to ensure safe and efficient operation. However, when the material after the first stage reaction is completed enters the second stage, there will be a transition zone between the first stage and the second stage. When the material passes through the transition zone and enters the second stage, the temperature of the material is difficult to control, and there is a problem of too high or too low temperature, resulting in poor reaction effect when the material just enters the second stage, thereby producing more by-products and reducing product quality. Summary of the invention

[0005] The purpose of the utility model is to solve the above problems existing in the prior art and propose a multi-stage tubular reactor, which solves the technical problem of how to accurately control the temperature of materials and improve product quality.

[0006] The purpose of the utility model can be achieved through the following technical solutions: a multi-stage tubular reactor, comprising a first reaction tube with a feed port at the bottom and a second reaction tube with a discharge port at the top, wherein a plurality of first heat exchange tubes are arranged in the middle of the first reaction tube, and a first heat exchange cavity is formed between the inner wall of the first reaction tube and the outer walls of all the first heat exchange tubes, and a plurality of second heat exchange tubes are arranged in the middle of the second reaction tube, and a second heat exchange cavity is formed between the inner wall of the second reaction tube and the outer walls of all the second heat exchange tubes, characterized in that a transition tube is arranged between the first reaction tube and the second reaction tube, and a third heat exchange tube arranged in a serpentine shape is arranged in the transition tube, and the third heat exchange tube is arranged as a whole along the radial direction of the transition tube, and the feed port is connected with the discharge port through the first heat exchange tube, the transition tube and the second heat exchange tube.

[0007] The material enters the first heat exchange tube from the feed port, then enters the transition tube from the first heat exchange tube, then enters the second heat exchange tube from the transition tube, and finally is discharged from the discharge port. The material reacts in the first heat exchange tube and exchanges heat with the medium in the first heat exchange chamber. When the material enters the transition tube, it exchanges heat with the material through the third heat exchange tube to control the temperature of the material so that the material entering the second reaction tube is within a reasonable temperature range to avoid excessive by-products in the second reaction tube. At the same time, the medium in the second heat exchange chamber exchanges heat with the material in the second reaction tube so that the material in the second reaction tube reacts better, thereby accurately controlling the temperature of the material and improving product quality.

[0008] In the above-mentioned multi-stage tubular reactor, a first heat exchange fin is spirally welded and fixedly connected to the circumferential outer wall of the first heat exchange tube, and a plurality of first flow grooves arranged along the axial direction of the first heat exchange tube are arranged at intervals on the outer wall of the first heat exchange fin. The first heat exchange fin is fixedly connected to the first heat exchange tube by laser welding, and the arrangement of the first flow groove ensures the flow cross-sectional area, and does not hinder the flow of the heat medium while increasing the heat exchange area of ​​the first heat exchange fin.

[0009] In the above-mentioned multi-stage tubular reactor, a second heat exchange fin is spirally welded and fixedly connected to the circumferential outer wall of the second heat exchange tube, and a plurality of second flow grooves arranged along the axial direction of the second heat exchange tube are arranged at intervals on the outer wall of the second heat exchange fin. The second heat exchange fin is fixedly connected to the second heat exchange tube by laser welding, and the second flow groove is arranged to ensure the flow cross-sectional area, which will not hinder the flow of heat medium while increasing the heat exchange area of ​​the second heat exchange fin.

[0010] In the above-mentioned multi-stage tubular reactor, the transition tube is further provided with a first orifice plate, the first orifice plate is arranged along the radial direction of the transition tube, the outer peripheral wall of the first orifice plate is closely fitted with the inner side wall of the transition tube, the first orifice plate is located between the second heat exchange tube and the third heat exchange tube, and the first orifice plate has a plurality of first water holes passing through. The arrangement of the first orifice plate and the first water holes allows the material to flow in a set direction, so that the material entering the second reaction tube is orderly, thereby accurately controlling the temperature of the material and improving the product quality.

[0011] In the above-mentioned multi-stage tubular reactor, a plurality of first fixing plates are fixedly connected in the transition tube, and the third heat exchange tube is fixedly connected to the first fixing plates. The provision of the first fixing plates can improve the firmness of the third heat exchange tube and improve the stability of the third heat exchange tube.

[0012] In the above-mentioned multi-stage tubular reactor, a third heat exchange fin is welded and fixedly connected to the outer wall of the third heat exchange tube. The third heat exchange fin is provided to increase the heat exchange area and improve the heat exchange effect.

[0013] In the above-mentioned multi-stage tubular reactor, the bottom of the first reaction tube is a feed section, and a fourth heat exchange tube arranged in a serpentine shape is provided in the feed section, and the fourth heat exchange tube is arranged along the radial direction of the first reaction tube as a whole. The fourth heat exchange tube can perform heat exchange with the material just entering, so that the material entering the first reaction tube is within a reasonable temperature range, avoiding the generation of excessive by-products in the first reaction tube, and improving product quality.

[0014] In the above-mentioned multi-stage tubular reactor, a plurality of second fixing plates are fixedly connected in the feed section, and the fourth heat exchange tube is fixedly connected to the second fixing plate. The second fixing plate can improve the firmness of the fourth heat exchange tube and improve the stability of the fourth heat exchange tube.

[0015] In the above-mentioned multi-stage tubular reactor, a fourth heat exchange fin is welded and fixedly connected to the outer wall of the fourth heat exchange tube. The fourth heat exchange fin is provided to increase the heat exchange area and improve the heat exchange effect.

[0016] In the above-mentioned multi-stage tubular reactor, a second orifice plate is further provided in the feed section, the second orifice plate is arranged along the radial direction of the first reaction tube, the outer peripheral wall of the second orifice plate is closely fitted with the inner wall of the first reaction tube, the second orifice plate is located between the first heat exchange tube and the fourth heat exchange tube, and the second orifice plate has a plurality of second water holes passing therethrough. The second orifice plate and the second water holes are arranged so that the material flows in a set direction, and the material entering the first reaction tube is orderly, so that the temperature of the material can be accurately controlled and the product quality can be improved.

[0017] Compared with the prior art, the multi-stage tubular reactor provided by the utility model has the following advantages:

[0018] 1. The multi-stage tubular reactor is provided with a third heat exchange tube in the transition tube. The third heat exchange tube exchanges heat with the material entering the transition tube to control the temperature of the material so that the material entering the second reaction tube is within a reasonable temperature range, thereby avoiding the generation of excessive by-products in the second reaction tube and improving product quality.

[0019] 2. The multi-stage tubular reactor is provided with a fourth heat exchange tube in the feed section of the first reaction tube. The fourth heat exchange tube exchanges heat with the material just entering to control the temperature of the material so that the material entering the first reaction tube is within a reasonable temperature range, thereby avoiding the generation of excessive by-products in the first reaction tube and improving product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the multi-stage tubular reactor.

[0021] Figure 2 It is a schematic diagram of the arrangement of the first heat exchange tube of the multi-stage tube-in-tube reactor.

[0022] Figure 3 It is a schematic diagram of the arrangement of the second heat exchange tube of the multi-stage tube-in-tube reactor.

[0023] Figure 4 It is a schematic diagram of the structure of the third heat exchange tube of the multi-stage shell-and-tube reactor.

[0024] Figure 5 It is a schematic diagram of the structure of the fourth heat exchange tube of the multi-stage tube-in-tube reactor.

[0025] In the figure, 1, first reaction tube; 101, feed port; 102, feed section; 2, second reaction tube; 201, discharge port; 3, first heat exchange tube; 31, first flow slot; 4, first heat exchange cavity; 5, second heat exchange tube; 51, second flow slot; 6, second heat exchange cavity; 7, transition tube; 8, third heat exchange tube; 9, first heat exchange fin; 10, second heat exchange fin; 11, first orifice plate; 111, first water hole; 12, first fixed plate; 13, third heat exchange fin; 14, fourth heat exchange tube; 15, second fixed plate; 16, fourth heat exchange fin; 17, second orifice plate; 171, second water hole. DETAILED DESCRIPTION

[0026] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0027] like Figure 1As shown, the multi-stage shell-and-tube reactor includes a first reaction tube 1, a second reaction tube 2, a first heat exchange tube 3, a second heat exchange tube 5, a transition tube 7, a third heat exchange tube 8, a first heat exchange fin 9, a second heat exchange fin 10, a first orifice plate 11, a first fixed plate 12, a third heat exchange fin 13, a fourth heat exchange tube 14, a second fixed plate 15, a fourth heat exchange fin 16 and a second orifice plate 17.

[0028] The bottom of the first reaction tube 1 is a feed section 102 , and the bottom of the feed section 102 has a feed port 101 . The top of the second reaction tube 2 has a discharge port 201 . The second reaction tube 2 is located above the first reaction tube 1 , and a transition tube 7 is provided between the first reaction tube 1 and the second reaction tube 2 .

[0029] like Figure 2 As shown, seven first heat exchange tubes 3 are spaced apart in the first reaction tube 1, and first heat exchange fins 9 are spirally welded and fixedly connected to the circumferential outer wall of the first heat exchange tube 3. First flow grooves 31 arranged along the axial direction of the first heat exchange tube 3 are spaced apart on the outer wall of the first heat exchange fin 9, and a first heat exchange cavity 4 is formed between the inner wall of the first reaction tube 1 and the outer walls of all the first heat exchange tubes 3. In actual production, the number of the first heat exchange tubes 3 can be five or nine.

[0030] like Figure 3 As shown, seven second heat exchange tubes 5 are arranged in the second reaction tube 2, and second heat exchange fins 10 are spirally welded and fixedly connected to the circumferential outer wall of the second heat exchange tube 5. Second flow grooves 51 arranged along the axial direction of the second heat exchange tube 5 are arranged at intervals on the outer wall of the second heat exchange fin 10, and a second heat exchange cavity 6 is formed between the inner wall of the second reaction tube 2 and the outer walls of all the second heat exchange tubes 5. In actual production, the number of the second heat exchange tubes 5 can be five or nine.

[0031] like Figure 4 As shown, the transition pipe 7 is provided with a third heat exchange tube 8 arranged in a serpentine shape, and the third heat exchange tube 8 is arranged along the radial direction of the transition pipe 7 as a whole, and a third heat exchange fin 13 is fixedly connected to the outer wall of the third heat exchange tube 8. In this embodiment, two first fixing plates 12 are fixedly connected to the transition pipe 7, and the third heat exchange tube 8 is fixedly connected to the first fixing plates 12. In actual production, the number of the first fixing plates 12 is three or four. The transition pipe 7 is also provided with a first orifice plate 11, which is arranged along the radial direction of the transition pipe 7. The outer peripheral wall of the first orifice plate 11 is tightly fitted with the inner wall of the transition pipe 7. The first orifice plate 11 is located between the second heat exchange tube 5 and the third heat exchange tube 8, and the first orifice plate 11 has a first water hole 111 that penetrates through it.

[0032] like Figure 5As shown, the feed section 102 is provided with a fourth heat exchange tube 14 arranged in a serpentine shape, and the fourth heat exchange tube 14 is arranged along the radial direction of the first reaction tube 1 as a whole, and a fourth heat exchange fin 16 is fixedly connected to the outer wall of the fourth heat exchange tube 14. In this embodiment, two second fixing plates 15 are fixedly connected to the feed section 102, and the fourth heat exchange tube 14 is fixedly connected to the second fixing plates 15. In actual production, the number of the second fixing plates 15 is three or four. The feed section 102 is also provided with a second orifice plate 17, which is arranged along the radial direction of the first reaction tube 1, and the outer peripheral wall of the second orifice plate 17 is tightly fitted with the inner wall of the first reaction tube 1, and the second orifice plate 17 is located between the first heat exchange tube 3 and the fourth heat exchange tube 14, and the second orifice plate 17 has a second water hole 171 that penetrates through it.

[0033] During operation, the material enters the feed section 102 through the feed port 101, exchanges heat with the material through the fourth heat exchange tube 14, then enters the first heat exchange tube 3 through the second water hole 171 of the second orifice plate 17, exchanges heat with the medium in the first heat exchange chamber 4, then enters the transition tube 7 from the first heat exchange tube 3, exchanges heat with the third heat exchange tube 8, then enters the second heat exchange tube 5 through the first water hole 111 of the first orifice plate 11, exchanges heat with the medium in the second heat exchange chamber 6, and is finally discharged from the discharge port 201.

[0034] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0035] Although the terms such as the first reaction tube 1, the feed port 101, the feed section 102, the second reaction tube 2, the discharge port 201, the first heat exchange tube 3, the first flow slot 31, the first heat exchange chamber 4, the second heat exchange tube 5, the second flow slot 51, the second heat exchange chamber 6, the transition tube 7, the third heat exchange tube 8, the first heat exchange fin 9, the second heat exchange fin 10, the first orifice plate 11, the first water hole 111, the first fixed plate 12, the third heat exchange fin 13, the fourth heat exchange tube 14, the second fixed plate 15, the fourth heat exchange fin 16, the second orifice plate 17, the second water hole 171 are used more frequently in this article, the possibility of using other terms is not excluded. The use of these terms is only for the purpose of more conveniently describing and explaining the essence of the utility model; interpreting them as any additional restrictions is contrary to the spirit of the utility model.

Claims

1. A multi-stage tubular reactor, comprising a first reaction tube (1) having a feed inlet (101) at the bottom and a second reaction tube (2) having a discharge outlet (201) at the top, wherein a plurality of first heat exchange tubes (3) are arranged in the middle of the first reaction tube (1), a first heat exchange cavity (4) is formed between the inner wall of the first reaction tube (1) and the outer walls of all the first heat exchange tubes (3), a plurality of second heat exchange tubes (5) are arranged in the middle of the second reaction tube (2), a second heat exchange cavity (6) is formed between the inner wall of the second reaction tube (2) and the outer walls of all the second heat exchange tubes (5), characterized in that A transition tube (7) is provided between the first reaction tube (1) and the second reaction tube (2), and a third heat exchange tube (8) arranged in a serpentine shape is provided in the transition tube (7). The third heat exchange tube (8) is arranged as a whole along the radial direction of the transition tube (7), and the feed port (101) is connected to the discharge port (201) through the first heat exchange tube (3), the transition tube (7), and the second heat exchange tube (5).

2. A multi-stage tubular reactor according to claim 1, characterized in that: A first heat exchange fin (9) is spirally welded and fixedly connected to the circumferential outer wall of the first heat exchange tube (3), and a plurality of first flow grooves (31) arranged along the axial direction of the first heat exchange tube (3) are provided at intervals on the outer wall of the first heat exchange fin (9).

3. A multi-stage tubular reactor according to claim 1, characterized in that: A second heat exchange fin (10) is spirally welded and fixedly connected to the circumferential outer wall of the second heat exchange tube (5), and a plurality of second flow grooves (51) arranged along the axial direction of the second heat exchange tube (5) are provided at intervals on the outer wall of the second heat exchange fin (10).

4. A multi-stage tubular reactor according to claim 1, 2 or 3, characterized in that: The transition pipe (7) is also provided with a first orifice plate (11), which is arranged along the radial direction of the transition pipe (7), and the outer peripheral wall of the first orifice plate (11) is tightly fitted with the inner wall of the transition pipe (7). The first orifice plate (11) is located between the second heat exchange pipe (5) and the third heat exchange pipe (8), and the first orifice plate (11) has a plurality of first water holes (111) penetrating therethrough.

5. A multi-stage tubular reactor according to claim 1, 2 or 3, characterized in that: A plurality of first fixing plates (12) are fixedly connected in the transition pipe (7), and the third heat exchange pipe (8) is fixedly connected to the first fixing plate (12).

6. A multi-stage tubular reactor according to claim 1, 2 or 3, characterized in that: A third heat exchange fin (13) is welded and fixedly connected to the outer wall of the third heat exchange tube (8).

7. A multi-stage tubular reactor according to claim 1, 2 or 3, characterized in that: The bottom of the first reaction tube (1) is a feed section (102), and a fourth heat exchange tube (14) arranged in a serpentine shape is provided in the feed section (102). The fourth heat exchange tube (14) is arranged as a whole along the radial direction of the first reaction tube (1).

8. A multi-stage tubular reactor according to claim 7, characterized in that: A plurality of second fixing plates (15) are fixedly connected in the feed section (102), and the fourth heat exchange tube (14) is fixedly connected to the second fixing plates (15).

9. The multi-stage tubular reactor according to claim 7, characterized in that: A fourth heat exchange fin (16) is welded and fixedly connected to the outer wall of the fourth heat exchange tube (14).

10. The multi-stage tubular reactor according to claim 7, characterized in that: The feed section (102) is also provided with a second orifice plate (17), the second orifice plate (17) is arranged along the radial direction of the first reaction tube (1), the outer peripheral wall of the second orifice plate (17) is tightly fitted with the inner wall of the first reaction tube (1), the second orifice plate (17) is located between the first heat exchange tube (3) and the fourth heat exchange tube (14), and the second orifice plate (17) has a plurality of second water holes (171) penetrating therethrough.

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