Heat exchange device for ethylene glycol production

Abstract

The utility model discloses a heat exchange device for ethylene glycol production, which belongs to the technical field of heat exchange equipment and comprises a shell and a heat exchange tube, two ends of the shell are closed, the heat exchange tube penetrates through the shell, and a steam inlet tube and a steam discharge tube are respectively mounted at two ends of the shell. The heat exchange pipe comprises a cold water inlet pipe, a cold water discharge pipe and a telescopic spiral pipe capable of axially stretching out and drawing back, the cold water inlet pipe is movably installed at one end of the shell in a sealed mode, and the cold water discharge pipe is fixedly installed at the other end of the shell; a motor is arranged at the end of the shell, and a driving structure is arranged between the motor and the cold water inlet pipe. According to the heat exchange device for ethylene glycol production, flexible adjustment of the exposed heat exchange area of the heat exchange pipe is achieved through the first spiral pipe and the second spiral pipe which can be matched with each other, imbalance of the temperature of cooling water caused by fluctuation of the steam amount is effectively avoided, and the temperature stability of the cooling water is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of heat exchange equipment, and in particular relates to a heat exchange device for ethylene glycol production. Background Art

[0002] In modern chemical production, ethylene glycol, as an important chemical raw material, is widely used in the production of plastics, fibers and other chemical products. Ethylene glycol requires high-temperature heating during production, and electric heating equipment is generally configured in the reaction tank equipment. A large amount of high-temperature steam is also generated during production. Generally, a steam pipe is set at the top, and the steam pipe is used to guide the high-temperature steam to the heat exchange equipment for waste heat recovery.

[0003] In the production of ethylene glycol, steam plays a key role as a heat source in heat exchangers. However, because the steam flow and temperature are affected by production process conditions, it is difficult to regulate them to maintain a constant level at the waste heat collection point. Existing heat exchangers are typically designed with a fixed heat exchange tube area. When the steam supply fluctuates, the heat conversion of the heat exchanger is also limited, and it is impossible to stably provide water at the temperature required by subsequent processes. When the steam supply is insufficient, the heat exchange efficiency decreases, and the cooling water temperature cannot reach the expected value. When the steam supply is too high, the cooling water temperature may be too high, which not only affects the efficiency of the hot water in subsequent processes, but also increases the energy loss of the equipment, thus affecting the economic and stability of the overall production.

[0004] To this end, we propose a heat exchange device for ethylene glycol production to solve the above problems. Utility Model Content

[0005] The purpose of the utility model is to solve the problem that when the steam supply fluctuates, the heat conversion of the heat exchanger is also limited, and water with a temperature suitable for subsequent process requirements cannot be stably provided. A heat exchange device for ethylene glycol production is proposed.

[0006] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A heat exchange device for ethylene glycol production, comprising a shell and a heat exchange tube, wherein both ends of the shell are closed, the heat exchange tube is arranged through the shell, and a steam inlet pipe and a steam exhaust pipe are respectively installed at both ends of the shell;

[0008] The heat exchange tube includes a cold water inlet pipe, a cold water discharge pipe, and an axially retractable telescopic spiral pipe, wherein the cold water inlet pipe is sealably mounted on one end of the shell, and the cold water discharge pipe is fixedly mounted on the other end of the shell. The cold water inlet pipe, the cold water discharge pipe, and the telescopic spiral pipe are coaxial, and the two ends of the telescopic spiral pipe are respectively fixedly connected to the cold water inlet pipe and the cold water discharge pipe;

[0009] A motor is provided at the end of the shell, and a driving structure is provided between the motor and the cold water inlet pipe. When the cold water inlet pipe rotates, the telescopic spiral pipe can be controlled to change its length.

[0010] Preferably, the telescopic spiral tube includes a first spiral tube and a second spiral tube, the spiral radius and pitch of the first spiral tube and the second spiral tube are the same, and the outer diameter of the first spiral tube is consistent with the inner diameter of the second spiral tube, so that the first spiral tube can be screwed into the second spiral tube.

[0011] Preferably, an interlayer is provided in the shell, and the interlayer is a vacuum interlayer.

[0012] Preferably, the steam inlet pipe and the cold water exhaust pipe are located on the same side, and the steam exhaust pipe and the cold water inlet pipe are located on the same side.

[0013] Preferably, the driving structure includes a driving gear fixedly arranged at the output end of the motor, and the outer wall of the cold water inlet pipe is provided with a plurality of long racks distributed in a circumferential array, and the driving gear is meshed with the long racks.

[0014] Preferably, the outer sliding sleeve of the cold water inlet pipe is provided with a sliding sleeve, the inner hole of the sliding sleeve is adapted to the long rack outside the cold water inlet pipe, and the sliding sleeve is sealingly rotatably connected to the end of the shell.

[0015] Preferably, a thermometer is provided on the cold water drain pipe, and the thermometer is electrically connected to the motor.

[0016] Preferably, a drain pipe is provided at the bottom of the shell, and the drain pipe is a U-shaped pipe.

[0017] To sum up, the technical effects and advantages of the utility model are as follows: the heat exchange device for ethylene glycol production realizes flexible adjustment of the heat exchange area exposed by the heat exchange tube by rotating the first spiral tube and changing the length of the telescopic spiral tube through the first spiral tube and the second spiral tube that can cooperate with each other. By changing the length of the telescopic spiral tube, precise control of the heat exchange area can be achieved. When the steam flow rate increases, the heat exchange area is automatically reduced to avoid excessively high cooling water temperature; and when the steam flow rate is small, the heat exchange area is appropriately increased to ensure that the cooling water temperature meets the process requirements, effectively avoiding the imbalance of cooling water temperature caused by steam volume fluctuations, improving the temperature stability of the cooling water, and making it more in line with the precise temperature requirements of subsequent processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the appearance structure of the utility model;

[0019] Figure 2 This is a schematic diagram of the internal structure of the utility model;

[0020] Figure 3This is a schematic diagram of the cross-sectional structure of the utility model;

[0021] Figure 4 This is a schematic diagram of the structure of the heat exchange tube in the utility model;

[0022] Figure 5 It is a structural schematic diagram of the telescopic spiral tube in the utility model.

[0023] In the figure: 1. Outer shell; 11. Steam inlet pipe; 12. Steam exhaust pipe; 13. Interlayer; 14. Liquid discharge pipe; 2. Heat exchange tube; 21. Cold water inlet pipe; 22. Telescopic spiral tube; 221. First spiral tube; 222. Second spiral tube; 23. Cold water exhaust pipe; 24. Long rack; 25. Thermometer; 3. Motor; 31. Drive gear; 4. Sleeve. DETAILED DESCRIPTION

[0024] Reference Figure 1-3 A heat exchange device for ethylene glycol production includes a shell 1 and a heat exchange tube 2. Both ends of the shell 1 are closed. An interlayer 13 is provided inside the shell 1. The interlayer 13 is a vacuum interlayer. The interlayer 13 can effectively reduce heat conduction and heat convection, thereby reducing heat loss and maintaining the stability of the internal temperature of the shell 1. The heat exchange tube 2 is set through the shell 1, and the hot and cold media exchange heat in the shell 1, wherein steam is passed into the shell 1 and cold water is passed into the heat exchange tube 2. The heat exchange tube 2 is heated by the high-temperature steam, so that the cold water in the heat exchange tube 2 is heated for use in subsequent processes. A steam inlet pipe 11 and a steam exhaust pipe 12 are respectively installed at both ends of the shell 1. Steam enters the shell 1 through the steam inlet pipe 11, fills the internal space of the shell 1, and is discharged from the steam exhaust pipe 12 after completing the heat exchange.

[0025] The heat exchange tube 2 includes a cold water inlet pipe 21, a cold water discharge pipe 23 and a telescopic spiral pipe 22 that can be axially extended. The cold water inlet pipe 21 is sealed and movably installed at one end of the shell 1, and the cold water discharge pipe 23 is fixedly installed at the other end of the shell 1. The cold water inlet pipe 21, the cold water discharge pipe 23 and the telescopic spiral pipe 22 are in a coaxial state, and the two ends of the telescopic spiral pipe 22 are fixedly connected to the cold water inlet pipe 21 and the cold water discharge pipe 23 respectively. Cold water enters from the cold water inlet pipe 21, flows through the telescopic spiral pipe 22 and is discharged through the cold water discharge pipe 23. The telescopic spiral pipe The tube 22 is a rigid copper alloy tube with high thermal conductivity. When the cold water flows through the telescopic spiral tube 22, it exchanges heat with the steam inside the shell 1, causing the cold water in the telescopic spiral tube 22 to heat up. The cold water inlet pipe 21 can rotate and retract freely. When the cold water inlet pipe 21 rotates, the length of the telescopic spiral tube 22 changes. When the length of the telescopic spiral tube 22 changes, the corresponding heat exchange area will also change. At the same time, the residence time of the cold water in the telescopic spiral tube 22 will also change, thereby controlling the storage temperature of the cold water under different steam working conditions.

[0026] A motor 3 is provided at the end of the housing 1 , and a driving structure is provided between the motor 3 and the cold water inlet pipe 21 . When the cold water inlet pipe 21 rotates, the telescopic spiral tube 22 can be controlled to change its length.

[0027] Specifically, during the production of ethylene glycol, due to the continuous changes in process conditions and reaction processes, the amount of steam generated and the steam temperature are also different. When the steam working condition is large, the telescopic spiral tube 22 is controlled to be shortened. Under the same cold water flow rate, the residence time of cold water in the heat exchange tube 2 is reduced, and the heat exchange area is reduced. Therefore, the heating rate of cold water is also reduced, which can avoid the cold water output temperature being too high due to excessive steam. When the steam working condition is small, the telescopic spiral tube 22 is controlled to be extended. Under the same cold water flow rate, the residence time of cold water in the heat exchange tube 2 is increased, and the heat exchange area is increased. Therefore, the heating rate of cold water is also increased. When the steam working condition is small, the telescopic spiral tube 22 is controlled to be extended. Under the same cold water flow rate, the residence time of cold water in the heat exchange tube 2 is increased, and the heat exchange area is increased. Therefore, the heating rate of cold water is also increased. When the steam is too small, the heat exchange efficiency can be improved and the cold water output temperature can be increased.

[0028] Reference Figure 3-5 The telescopic spiral tube 22 includes a first spiral tube 221 and a second spiral tube 222. The first spiral tube 221 and the second spiral tube 222 are spiral-shaped and have a longer tortuous flow path, which can provide a larger heat exchange surface area. Under the same volume, a higher heat exchange capacity can be achieved, thereby improving the overall performance of the heat exchange device. The spiral radius and pitch of the first spiral tube 221 and the second spiral tube 222 are the same, and the outer tube diameter of the first spiral tube 221 is consistent with the inner tube diameter of the second spiral tube 222. The first spiral tube 221 and the second spiral tube 222 are in a coaxial state. When the first spiral tube 221 is rotated, when the axial displacement of the first spiral tube 221 is not restricted, the first spiral tube 221 can be screwed into the second spiral tube 222, so that the heat exchange areas of the first spiral tube 221 and the second spiral tube 222 partially overlap, thereby realizing the adjustment of the heat exchange area of ​​the heat exchange tube 2.

[0029] Reference Figure 1-3 The steam inlet pipe 11 and the cold water exhaust pipe 23 are located on the same side, and the steam exhaust pipe 12 and the cold water inlet pipe 21 are located on the same side, so that the steam flow direction and the cold water flow direction are opposite. The countercurrent design makes the temperature difference between the steam and the cold water remain large throughout the heat exchange process. Since the greater the temperature difference, the higher the heat transfer efficiency, it helps to achieve higher heat exchange efficiency.

[0030] Reference Figure 1-3 A thermometer 25 is provided on the cold water discharge pipe 23. The thermometer 25 can monitor the outlet water temperature in real time. The thermometer 25 is electrically connected to the motor 3. When the outlet water temperature changes, the motor 3 is controlled to rotate to achieve control of the length of the telescopic spiral tube 22.

[0031] Reference Figure 1-5The driving structure includes a driving gear 31 fixedly arranged at the output end of the motor 3. A plurality of long racks 24 distributed in a circumferential array are provided on the outer wall of the cold water inlet pipe 21. The driving gear 31 is engaged with the long rack 24. When the motor 3 is started, the driving gear 31 rotates, thereby driving the long rack 24 to rotate the cold water inlet pipe 21. Since the long rack 24 has a long length, it can maintain an engagement state with the driving gear 31 when the cold water inlet pipe 21 is axially displaced.

[0032] In order to ensure the sealing between the cold water inlet pipe 21 and the outer shell 1 and not affect the movement of the cold water inlet pipe 21, a sliding sleeve 4 is provided on the outer sliding sleeve of the cold water inlet pipe 21. The inner hole of the sliding sleeve 4 is adapted to the long rack 24 outside the cold water inlet pipe 21. The sliding sleeve 4 is sealed and rotatably connected to the end of the outer shell 1. When the cold water inlet pipe 21 rotates, the sliding sleeve 4 rotates with the outer shell 1. When the cold water inlet pipe 21 moves axially, the long rack 24 cooperates with the sliding sleeve 4 to maintain the seal.

[0033] A drain pipe 14 is provided at the bottom of the shell 1. The drain pipe 14 is a U-shaped pipe. The condensed water formed when the steam exchanges heat on the surface of the heat exchange tube 2 can be discharged outward through the drain pipe 14. The U-shaped drain pipe 14 allows the condensed water to be partially accumulated at the bend of the drain pipe 14 to achieve sealing, which can prevent steam from overflowing.

[0034] Working principle:

[0035] The steam discharge pipe on the ethylene glycol reaction tank is connected to the steam inlet pipe 11. Steam enters the shell 1 through the steam inlet pipe 11, fills the internal space of the shell 1, and is discharged outward from the steam discharge pipe 12. Cold water enters from the cold water inlet pipe 21, flows through the telescopic spiral pipe 22, and is discharged through the cold water discharge pipe 23. The high-temperature steam heats the heat exchange tube 2, so that the cold water in the heat exchange tube 2 is heated for use in subsequent processes.

[0036] The outlet water temperature is monitored in real time by the thermometer 25. When the outlet water temperature changes, the motor 3 is controlled to rotate, so that the driving gear 31 rotates, and then the long rack 24 is driven to rotate the cold water inlet pipe 21. The first spiral tube 221 can be screwed into the second spiral tube 222, so that the heat exchange areas of the first spiral tube 221 and the second spiral tube 222 partially overlap, thereby realizing the control of the length of the telescopic spiral tube 22 and the adjustment of the heat exchange area of ​​the heat exchange tube 2.

Claims

1. A heat exchange device for ethylene glycol production, comprising a housing (1) and a heat exchange tube (2), wherein both ends of the housing (1) are closed, and the heat exchange tube (2) is arranged to penetrate the housing (1), characterized in that: A steam inlet pipe (11) and a steam exhaust pipe (12) are respectively installed at both ends of the shell (1); The heat exchange tube (2) comprises a cold water inlet pipe (21), a cold water discharge pipe (23), and an axially retractable telescopic spiral pipe (22), wherein the cold water inlet pipe (21) is sealingly mounted on one end of the housing (1), and the cold water discharge pipe (23) is fixedly mounted on the other end of the housing (1); the cold water inlet pipe (21), the cold water discharge pipe (23), and the telescopic spiral pipe (22) are in a coaxial state, and both ends of the telescopic spiral pipe (22) are fixedly connected to the cold water inlet pipe (21) and the cold water discharge pipe (23), respectively; A motor (3) is provided at the end of the housing (1), and a driving structure is provided between the motor (3) and the cold water inlet pipe (21). When the cold water inlet pipe (21) rotates, the telescopic spiral pipe (22) can be controlled to change its length.

2. A heat exchange device for ethylene glycol production according to claim 1, characterized in that: The telescopic spiral tube (22) comprises a first spiral tube (221) and a second spiral tube (222); the spiral radius and pitch of the first spiral tube (221) and the second spiral tube (222) are the same, and the outer diameter of the first spiral tube (221) is consistent with the inner diameter of the second spiral tube (222), so that the first spiral tube (221) can be screwed into the second spiral tube (222).

3. A heat exchange device for ethylene glycol production according to claim 1, characterized in that: An interlayer (13) is provided in the outer shell (1), and the interlayer (13) is a vacuum interlayer.

4. A heat exchange device for ethylene glycol production according to claim 1, characterized in that: The steam inlet pipe (11) and the cold water exhaust pipe (23) are located on the same side, and the steam exhaust pipe (12) and the cold water inlet pipe (21) are located on the same side.

5. The heat exchange device for ethylene glycol production according to claim 1, characterized in that: The driving structure comprises a driving gear (31) fixedly arranged at the output end of the motor (3); a plurality of long racks (24) distributed in a circumferential array are provided on the outer wall of the cold water inlet pipe (21); and the driving gear (31) meshes with the long racks (24).

6. A heat exchange device for ethylene glycol production according to claim 5, characterized in that: The outer sliding sleeve of the cold water inlet pipe (21) is provided with a sliding sleeve (4), the inner hole of the sliding sleeve (4) is adapted to the long rack (24) outside the cold water inlet pipe (21), and the sliding sleeve (4) is sealingly rotatably connected to the end of the outer shell (1).

7. A heat exchange device for ethylene glycol production according to claim 1, characterized in that: A thermometer (25) is provided on the cold water drain pipe (23), and the thermometer (25) is electrically connected to the motor (3).

8. The heat exchange device for ethylene glycol production according to claim 1, characterized in that: A drainage pipe (14) is provided at the bottom of the housing (1), and the drainage pipe (14) is a U-shaped pipe.

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