Tubular reactor

Abstract

The invention provides a tubular reactor, and belongs to the technical field of chemical equipment. The tubular reactor comprises a shell pass cylinder, a heat exchange tube is arranged in the shell pass cylinder, at least one medium inlet local guide cylinder and at least one medium outlet local guide cylinder are arranged on the outer wall face of the shell pass cylinder, and the included angle between the two ends of the medium inlet local guide cylinder and the two ends of the medium outlet local guide cylinder ranges from 60 degrees to 120 degrees. The medium inlet local guide cylinder and the medium outlet local guide cylinder are arranged on the outer wall surface of the shell pass cylinder, so that the heat exchange efficiency is improved, the heat exchange working condition is stable, the temperature gradient is small, the reaction is more comprehensive, the occurrence of temperature runaway working conditions is reduced, and the safety is also improved.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical equipment, and in particular relates to a tubular reactor. Background Art

[0002] The medium inlet and outlet pipes of the shell side of a large vertical shell-and-tube reactor are usually single and limited in size, so that after the medium fluid enters the equipment, it only exchanges heat with the shell and tube near the inlet in a short period of time, and the temperature distribution on the shell and tube is uneven. When the temperature gradient is large, it is in an unstable condition and the reactor is prone to temperature runaway. At the medium inlet / outlet, due to the small space, there is no space to ensure the effective heat removal of the shell and tube, and there is a stagnant area, which affects the heat exchange effect. In addition, the full-tube setting is adopted in the layout of the heat exchange tube, which makes the contact surface between the medium inlet and the heat exchange tube concentrated, and the heat exchange efficiency is further reduced. Summary of the invention

[0003] The object of the present invention is to solve the problems existing in the above-mentioned prior art and to provide a shell-and-tube reactor. By arranging at least one medium inlet local guide tube and at least one medium outlet local guide tube on the outer wall surface of the shell-side cylinder, the problem that the existing shell-and-tube reactor is prone to temperature runaway is solved, thereby improving the safety and stability of the reaction.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention provides a shell-and-tube reactor, comprising a shell-side cylinder, wherein heat exchange tubes are arranged in the shell-side cylinder, and at least one medium inlet local guide tube and at least one medium outlet local guide tube are arranged on the outer wall of the shell-side cylinder.

[0006] A further improvement of the present invention is:

[0007] An upper tube sheet and a lower tube sheet are respectively arranged at the upper and lower ends of the shell-side cylinder, and the heat exchange tube is fixed between the upper tube sheet and the lower tube sheet;

[0008] A plurality of baffles are arranged in the shell-side cylinder between the upper tube sheet and the lower tube sheet.

[0009] A further improvement of the present invention is:

[0010] The medium inlet local guide tube is located between the lower tube plate and the baffle plate close to the lower tube plate;

[0011] The angle between the two ends of the local guide tube at the medium inlet is 60 to 120 degrees.

[0012] A further improvement of the present invention is:

[0013] A medium inlet is arranged on the outer wall surface of the medium inlet local guide tube, and a plurality of medium inlet long slots are opened on the shell side cylinder wall surface within the range of the medium inlet local guide tube.

[0014] A further improvement of the present invention is:

[0015] The medium inflow long slot is parallel to the central axis of the shell-side cylinder and is located between the lower tube plate and the baffle plate close to the lower tube plate.

[0016] A further improvement of the present invention is:

[0017] The total area of ​​the medium flowing into the long slots exceeds the area of ​​the medium inlet, and at the same time, meets the heat exchange circumferential angle space requirements of the heat exchange tubes in the shell cylinder;

[0018] Preferably, the total area of ​​the medium flowing into the long slots is 1 to 1.2 times the area of ​​the medium inlet.

[0019] A further improvement of the present invention is:

[0020] The medium outlet local guide tube is located between the upper tube plate and the baffle plate close to the upper tube plate;

[0021] The angle between the two ends of the local guide tube at the medium outlet is 60 to 120 degrees.

[0022] A further improvement of the present invention is:

[0023] A medium outlet is arranged on the outer wall surface of the medium outlet local guide tube, and a plurality of medium outflow long slots are opened on the shell side cylinder wall surface within the range of the medium outlet local guide tube.

[0024] A further improvement of the present invention is:

[0025] The medium outflow long slot is parallel to the central axis of the shell-side cylinder and is located between the upper tube plate and the baffle plate close to the upper tube plate.

[0026] A further improvement of the present invention is:

[0027] The total area of ​​the medium outflow long slots exceeds the area of ​​the medium outlet and meets the heat exchange circumferential angle space requirements of the heat exchange tubes in the shell cylinder;

[0028] Preferably, the total area of ​​the medium outflow long slots is 1 to 1.2 times the medium outlet area.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention arranges at least one medium inlet local flow guide tube and at least one medium outlet local flow guide tube on the outer wall surface of the shell-side cylinder. Since there is a certain distance gap between the medium inlet local flow guide tube and the medium outlet local flow guide tube and the shell-side cylinder, a certain space is reserved at the medium inlet or the medium outlet for buffering and distribution of the medium, ensuring the contact between the maximum number of heat exchange tubes and the medium, achieving uniform and reasonable temperature distribution and maximization of the tube-to-tube heat exchange rate, and the heat exchange condition is stable, the temperature gradient is small, the reaction is more comprehensive, the occurrence of temperature runaway condition is reduced, and the safety is also improved.

[0031] In the present invention, the angles at both ends of the local guide tube at the medium inlet are set to 60 to 120 degrees. Firstly, it depends on the range of the medium flowing into the long slot around the shell cylinder, that is, it is necessary to ensure that the total area of ​​the medium flowing into the long slot meets the requirements. Secondly, it is related to the arrangement of the heat exchange tubes. Under the condition of not increasing the diameter of the shell cylinder, the number of the first row of heat exchange tubes close to the slot direction of the shell cylinder is as large as possible to achieve uniform temperature distribution and increase the heat exchange efficiency.

[0032] In the present invention, the angles at both ends of the local guide tube at the medium outlet are set to 60 to 120 degrees. Firstly, it depends on the range of the medium outflow long slot on the shell side cylinder around the shell side cylinder, that is, it is necessary to ensure that the total area of ​​the medium outflow long slot meets the requirements. Secondly, it is related to the arrangement of the heat exchange tubes. Under the condition of not increasing the diameter of the shell side cylinder, the number of the first row of heat exchange tubes close to the slot direction of the shell side cylinder is as large as possible to achieve uniform temperature distribution and increase the heat exchange efficiency.

[0033] The present invention provides a plurality of medium inlet long slots on the wall surface of the shell-side cylinder within the range of the local guide cylinder at the medium inlet. The fluid can flow to the position of the farthest medium inlet long slot in a short time, and the flow rate of the fluid at each medium inlet long slot can also be basically the same. In this way, the temperature and flow rate distributed to each heat exchange tube in the first row facing the medium inlet long slot in the shell-side cylinder are relatively uniform, forming efficient and uniform heat exchange and effectively controlling the occurrence of temperature runaway.

[0034] The present invention provides a plurality of medium outflow long slots on the wall surface of the shell-side cylinder within the range of the local guide cylinder at the medium outlet. The fluid can flow to the position of the farthest medium outflow long slot in a short time, and the flow rate of the fluid at each medium outflow long slot can also be basically the same. In this way, the temperature and flow rate distributed to each heat exchange tube in the first row facing the medium outflow long slot in the shell-side cylinder are relatively uniform, forming efficient and uniform heat exchange. At the same time, efficient heat removal is also achieved at the medium outlet, effectively controlling the occurrence of temperature runaway.

[0035] The tubular reactor of the present invention can operate stably and for a long time, reduce the number of replacements and maintenance times, and save time costs, device start-up and shutdown costs, and equipment replacement and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The present invention provides a schematic structural diagram of a shell-and-tube reactor;

[0037] Figure 2 This is a schematic diagram of the structure of the local guide tube at the medium inlet;

[0038] Figure 3 yes Figure 2 AA cross-section diagram;

[0039] Figure 4 yes Figure 3 B-direction cross-sectional view.

[0040] In the figure,

[0041] 1. Lower tube plate,

[0042] 2. Shell side cylinder,

[0043] 3. Baffle

[0044] 4. Heat exchange tubes,

[0045] 5. Upper tube plate,

[0046] 6. Local guide tube at medium outlet,

[0047] 7. Medium outlet,

[0048] 8. The medium flows out of the long slot.

[0049] 9. Local guide tube at the medium inlet,

[0050] 10. Medium import,

[0051] 11. The medium flows into the long slot. DETAILED DESCRIPTION

[0052] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0053] [Example 1]

[0054] This embodiment provides a shell-and-tube reactor, such as Figures 1 to 4 As shown, it includes a shell-side cylinder 2, in which a heat exchange tube 4 is arranged, and at least one medium inlet local guide cylinder 9 and at least one medium outlet local guide cylinder 6 are arranged on the outer wall surface of the shell-side cylinder 2.

[0055] The medium outlet local flow guide cylinder 6 is located above the medium inlet local flow guide cylinder 9 , and both ends of the medium outlet local flow guide cylinder 6 and the medium inlet local flow guide cylinder 9 are smoothly transitioned and fixed on the outer wall surface of the shell side cylinder 2 .

[0056] The present invention sets at least one medium inlet local flow guide tube 9 and at least one medium outlet local flow guide tube 6 on the shell side cylinder 2. Because there is a certain distance gap between the medium inlet local flow guide tube 9 and the medium outlet local flow guide tube 6 and the shell side cylinder 2, a certain space is left at the medium inlet and medium outlet for medium buffering and distribution, ensuring the maximum number of heat exchange tubes in contact with the medium, achieving uniform and reasonable temperature distribution and maximizing the heat exchange rate of the heat exchange tubes. Such a structure has a good effect on heat removal at the medium inlet and medium outlet, reduces possible temperature runaway conditions, and ensures safe and long-term operation.

[0057] The number of local guide tubes at the medium inlet and the medium outlet can be set to 1 or 2 according to the equipment size, baffle distribution, and heat exchange requirements. For example, when the shell cylinder diameter is large, the shell pressure drop is large. In order to reduce the pressure drop, the baffle adopts a double-bow form. At this time, according to the form of the baffle, considering the form with the best heat exchange efficiency, two local guide tubes are set for the medium inlet and two local guide tubes for the medium outlet.

[0058] [Example 2]

[0059] An upper tube sheet 5 and a lower tube sheet 1 are respectively arranged at the upper and lower ends of the shell-side cylinder 2, and both ends of the heat exchange tube 4 are respectively fixed on the upper tube sheet 5 and the lower tube sheet 1, and a plurality of baffles 3 are arranged between the upper tube sheet 5 and the lower tube sheet 1 in the shell-side cylinder 2.

[0060] like Figures 2 to 4 As shown, the medium inlet local guide tube 9 is located between the lower tube plate 1 and the baffle 3 close to the lower tube plate 1, and the angle between the two ends of the medium inlet local guide tube 9 is 60 to 120 degrees.

[0061] A medium inlet 10 is arranged on the outer wall surface of the medium inlet local guide tube 9, and a plurality of medium inlet long slots 11 are opened on the wall surface of the shell side cylinder 2 within the range of the medium inlet local guide tube 9. The medium inlet long slots 11 are parallel to the central axis of the shell side cylinder 2 and are located between the lower tube plate 1 and the baffle 3 close to the lower tube plate 1.

[0062] The total area of ​​the medium flowing into the long slots 11 exceeds the area of ​​the medium inlet 10 while meeting the circumferential angle space requirement of the heat exchange tubes in the shell-side cylinder 2. Preferably, the total area of ​​the medium flowing into the long slots 11 is 1 to 1.2 times the area of ​​the medium inlet 10.

[0063] The medium enters the medium inlet local guide tube 9 through the medium inlet 10 for buffering and distribution, and then flows into the shell-side cylinder 2 through the medium inlet long slot 11, ensuring the maximum number of heat exchange tubes in contact with the medium, achieving uniform and reasonable temperature distribution and maximizing the heat exchange rate of the heat exchange tubes, having a good effect on heat removal from the medium inlet 10, reducing possible temperature runaway conditions, and ensuring safe and long-term operation.

[0064] In the embodiment of the present invention, the angle between the two ends of the local guide tube 9 at the medium inlet is set to 60 to 120 degrees. First, it depends on the range of the medium inflow long slot 11 on the shell cylinder 2 around the cylinder, that is, to ensure that the total area of ​​the medium inflow long slot 11 meets the requirements (that is, the total area of ​​the medium inflow long slot 11 exceeds the area of ​​the medium inlet 10, while meeting the heat exchange circumferential angle space requirements of the heat exchange tubes in the shell cylinder 2. Preferably, the total area of ​​the medium inflow long slot 11 is 1 to 1.2 times the area of ​​the medium inlet 10). Second, it is related to the arrangement of the heat exchange tubes. Under the condition of not increasing the diameter of the shell cylinder, the number of the first row of heat exchange tubes close to the slot direction of the shell cylinder is as large as possible to achieve uniform temperature distribution and increase the heat exchange efficiency. According to existing project experience, when the angle between the two ends of the local guide tube is 60-120 degrees, the above two points can meet the relevant requirements.

[0065] Since the liquid flows in a convergent direction, the slots / holes farther from the inlet need to wait until the slots / holes closer to the inlet are filled before they can be filled successively; since the present invention provides a plurality of medium inlet long slots 11 on the wall of the shell-side cylinder 2 within the range of the local guide tube 9 of the medium inlet, the fluid can flow to the position of the farthest medium inlet long slot 11 in a short time, and the flow rate of the fluid at each medium inlet long slot 11 can also be basically the same, so that the temperature and flow rate distributed to each heat exchange tube in the first row facing the medium inlet long slot 11 in the shell-side cylinder 2 are relatively uniform, forming efficient and uniform heat exchange, and effectively controlling the occurrence of temperature runaway.

[0066] [Example 3]

[0067] The medium outlet local flow guide tube 6 is located between the upper tube plate 5 and the baffle plate 3 close to the upper tube plate 5, and the angle between the two ends of the medium outlet local flow guide tube 6 is 60 to 120 degrees.

[0068] A medium outlet 7 is arranged on the outer wall surface of the medium outlet local guide tube 6, and a plurality of medium outflow long slots 8 are opened on the wall surface of the shell side cylinder 2 within the range of the medium outlet local guide tube 6. The medium outflow long slots 8 are parallel to the central axis of the shell side cylinder 2 and are located between the upper tube plate 5 and the baffle 3 close to the upper tube plate 5.

[0069] The total area of ​​the medium outflow long slots 8 exceeds the area of ​​the medium outlet 7 while meeting the heat exchange circumferential angle space requirements of the heat exchange tubes in the shell cylinder. Preferably, the total area of ​​the medium outflow long slots 8 is 1 to 1.2 times the area of ​​the medium outlet 7.

[0070] The medium in the shell-side cylinder 2 flows out through the medium outflow long slot 8 to the medium outlet local guide tube 6 for buffering and distribution, and then flows out through the medium outlet 7, ensuring that the maximum number of heat exchange tubes are in contact with the medium, achieving uniform and reasonable temperature distribution and maximizing the heat exchange rate of the heat exchange tubes, having a good effect on heat removal at the medium outlet 7, reducing possible temperature runaway conditions, and ensuring safe and long-term operation.

[0071] In the embodiment of the present invention, the angle between the two ends of the local guide tube 6 at the medium outlet is set to 60 to 120 degrees. First, it depends on the range of the medium outflow long slot 8 on the shell cylinder 2 around the shell cylinder, that is, to ensure that the total area of ​​the medium outflow long slot 8 meets the requirements (that is, the total area of ​​the medium outflow long slot 8 exceeds the area of ​​the medium outlet 7, while meeting the heat exchange circumferential angle space requirements of the heat exchange tubes in the shell cylinder 2. Preferably, the total area of ​​the medium outflow long slot 8 is 1 to 1.2 times the area of ​​the medium outlet 7). Second, it is related to the arrangement of the heat exchange tubes. Under the condition of not increasing the diameter of the shell cylinder, the number of the first row of heat exchange tubes close to the slot direction of the shell cylinder is as large as possible to achieve uniform temperature distribution and increase the heat exchange efficiency. According to existing project experience, when the angle between the two ends of the local guide tube is 60-120 degrees, the above two points can meet the relevant requirements.

[0072] Since the liquid flows in a convergent direction, the slots / holes farther from the outlet need to wait until the slots / holes closer to the outlet are filled before they can be filled successively; since the present invention provides a plurality of medium outflow long slots 8 on the wall of the shell-side cylinder within the range of the local guide cylinder 6 of the medium outlet, the fluid can flow to the position of the farthest medium outflow long slot 8 in a short time, and the flow rate of the fluid at each medium outflow long slot 8 can also be basically the same, so that the temperature and flow rate distributed to each heat exchange tube in the first row facing the medium outflow long slot 8 in the shell-side cylinder 2 are relatively uniform, forming efficient and uniform heat exchange, and at the same time, efficient heat removal is achieved at the medium outlet, effectively controlling the occurrence of temperature runaway.

[0073] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0074] In the description of the present invention, unless otherwise specified, the terms "upper", "lower", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0075] The above technical solution is only one implementation mode of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the principles disclosed in the present invention, and it is not limited to the technical solution described in the above specific embodiments of the present invention. Therefore, the above description is only preferred and does not have a restrictive meaning.

Claims

1. A tubular reactor, characterized in that: It comprises a shell-side cylinder, in which a heat exchange tube is arranged, and at least one medium inlet local guide cylinder and at least one medium outlet local guide cylinder are arranged on the outer wall surface of the shell-side cylinder.

2. The shell-and-tube reactor according to claim 1, characterized in that: An upper tube sheet and a lower tube sheet are respectively arranged at the upper and lower ends of the shell-side cylinder, the heat exchange tube is fixed between the upper tube sheet and the lower tube sheet, and a plurality of baffles are arranged between the upper tube sheet and the lower tube sheet in the shell-side cylinder.

3. The shell-and-tube reactor according to claim 2, characterized in that: The medium inlet local guide tube is located between the lower tube plate and the baffle plate close to the lower tube plate; The angle between the two ends of the local guide tube at the medium inlet is 60 to 120 degrees.

4. The shell-and-tube reactor according to claim 3, characterized in that: A medium inlet is arranged on the outer wall surface of the medium inlet local guide tube, and a plurality of medium inlet long slots are opened on the shell side cylinder wall surface within the range of the medium inlet local guide tube.

5. The shell-and-tube reactor according to claim 4, characterized in that: The medium inflow long slot is parallel to the central axis of the shell-side cylinder and is located between the lower tube plate and the baffle plate close to the lower tube plate.

6. The shell-and-tube reactor according to claim 5, characterized in that: The total area of ​​the medium flowing into the long slots exceeds the area of ​​the medium inlet, and at the same time, meets the heat exchange circumferential angle space requirements of the heat exchange tubes in the shell cylinder; Preferably, the total area of ​​the medium flowing into the long slots is 1 to 1.2 times the medium inlet area.

7. The shell-and-tube reactor according to claim 2, characterized in that: The local guide tube of the medium outlet is located between the upper tube plate and the baffle plate close to the upper tube plate; The angle between the two ends of the local guide tube at the medium outlet is 60 to 120 degrees.

8. The shell-and-tube reactor according to claim 7, characterized in that: A medium outlet is arranged on the outer wall surface of the medium outlet local guide tube, and a plurality of medium outflow long slots are opened on the shell side cylinder wall surface within the range of the medium outlet local guide tube.

9. The shell-and-tube reactor according to claim 8, characterized in that: The medium outflow long slot is parallel to the central axis of the shell-side cylinder and is located between the upper tube plate and the baffle plate close to the upper tube plate.

10. The shell-and-tube reactor according to claim 9, characterized in that: The total area of ​​the medium outflow long slots exceeds the area of ​​the medium outlet and meets the heat exchange circumferential angle space requirements of the heat exchange tubes in the shell cylinder; Preferably, the total area of ​​the medium outflow long slots is 1 to 1.2 times the medium outlet area.

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