Fractionation system of etherified C4
By using components such as catalytic distillation towers and water cooling devices in the fractionation system, the liquefied distillation gas is cooled and refluxed to the catalytic distillation tower for cooling, which solves the problem that the air-cooling cooling effect is affected by the ambient temperature and improves fractionation efficiency.
Patent Information
- Application Number
- CN202421291538.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-06
- Publication Date
- 2025-03-07
- Estimated Expiration
- 2034-06-06
AI Technical Summary
The existing fractionation towers adopt air-cooling during the cooling process, which is greatly affected by the ambient temperature, resulting in a deterioration of the cooling effect, thereby reducing the fractionation efficiency.
The fractionation system of a catalytic distillation column, a water cooling device, a reflux tank and a splitting device is adopted to fractionate through a catalytic distillation column. The generated liquefied distillation gas is cooled in the water cooling device, and the cooled liquefied distillation gas is refluxed to the catalytic distillation column through a reflux tank and a splitting device for cooling.
The cooling effect in the fractionation column is improved, the pressure in the column is reduced, the fractionation efficiency is improved, and the introduction of new substances into the column is avoided.
Smart Images
Figure CN222566842U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of petrochemical industry, in particular to a post-ether C4 fractionation system. Background Art
[0002] As an important petroleum resource, C4 liquefied gas plays an increasingly important role in the field of chemical production. The comprehensive utilization of C4 is also becoming more and more extensive. Among them, the synthesis of methyl tert-butyl ether (MTBE) by reacting isobutylene in C4 hydrocarbons with methanol is the main way to utilize C4 in China.
[0003] MTBE is a high-octane gasoline additive. Its chemical oxygen content is much lower than that of methanol, which is beneficial for warming up the car and saving fuel. It has a low latent heat of evaporation, which is beneficial for cold starting. It is often used to blend unleaded gasoline and low-lead gasoline. It can also be re-cracked into isobutylene as a raw material for rubber and other chemical products. Therefore, the production and preparation of MTBE is an important part of petrochemical industry.
[0004] The production of MTBE is currently mainly to obtain olefin substances and MTBE through the MTBE device. Specifically, in the process of producing MTBE, the C4 raw material needs to be preset to a certain temperature after mixing with methanol before entering the etherification reactor for reaction. Further, the C4 product after the etherification reactor is fractionated by a fractionation tower to obtain the MTBE product. However, when the fractionation tower is performing the fractionation operation, it is necessary to heat the tower so that the MTBE with a higher boiling point can be fractionated. The heating temperature in the fractionation tower is usually about 120 degrees Celsius. The pressure in the tower will continue to increase during the operation of the fractionation tower, and the increase in the pressure in the tower will greatly reduce the fractionation effect of each product in the fractionation tower. Therefore, it is necessary to appropriately cool the tower to reduce the pressure in the tower. However, at present, when cooling the temperature in the fractionation tower, air cooling is usually used for cooling, and the air cooling method is greatly affected by the ambient temperature. In the hot summer, the ambient temperature is usually high, resulting in poor refrigeration effect of air cooling, thereby making the cooling effect in the fractionation tower poor, the pressure in the tower increases, and the fractionation efficiency of the fractionation tower poor. Utility Model Content
[0005] In view of this, in order to address the above shortcomings, it is necessary to propose a post-etherification C4 distillation system to reduce the temperature in the distillation tower and improve the distillation efficiency of the distillation tower.
[0006] The utility model provides a fractionation system for post-etherification C4, which comprises: a catalytic distillation tower, a water cooling device, a reflux tank and a diverter; the material inlet of the catalytic distillation tower is connected with the material outlet of the etherification reactor, so as to transport the etherified C4 product in the etherification reactor to the catalytic distillation tower, and the liquid phase outlet of the catalytic distillation tower is connected with the MTBE collecting device, so as to collect the separated MTBE; the gas phase outlet of the catalytic distillation tower is connected with the feed end of the water cooling device, so as to cool the liquefied distillation gas generated by the catalytic distillation tower through the water cooling device; the discharge end of the water cooling device is connected with the feed end of the reflux tank, and the discharge end of the reflux tank is connected with the feed end of the diverter; the diverter comprises a first discharge port and a second discharge port, the first discharge port is connected with the inside of the catalytic distillation tower, so as to cool the inside of the catalytic distillation tower by using the cooled liquefied distillation gas; the second discharge port is connected with the feed port of a subsequent methanol extraction tower.
[0007] Preferably, the water cooling device is provided with a first spray assembly for spraying cooling water on the material flow pipeline to cool the liquefied distillation gas in the material pipeline.
[0008] Preferably, the fractionation system further comprises an air cooling device, which is used to cool the cooling water in the water cooling device.
[0009] Preferably, the distillation system is also provided with a water pump, the water inlet end of the water cooling device is connected with the water outlet end of the cooling tower, and the water outlet end of the water cooling device is connected with the water inlet end of the cooling tower. The water pump is arranged on the pipeline between the water inlet end of the water cooling device and the water outlet end of the cooling tower, and is used to extract cooling water in the cooling tower to cool the liquefied distillation gas in the material flow pipeline.
[0010] Preferably, a reflux pump is provided on the pipeline between the first discharge port and the catalytic distillation tower for conveying the liquefied distillation gas output from the first discharge port to the catalytic distillation tower.
[0011] Preferably, a solenoid valve is provided between the reflux pump and the first discharge port.
[0012] Preferably, the distillation system also includes a pressure monitoring device and a main control device, and the pressure monitoring device, the reflux pump and the solenoid valve are all electrically connected to the main control device; the pressure monitoring device is arranged on the catalytic distillation tower, and is used to monitor the pressure inside the catalytic distillation tower, and upload the monitored pressure data to the main control device; the main control device is used to control the reflux pump and the solenoid valve according to the received pressure data, so as to adjust the flow rate of the liquefied distillation gas entering the catalytic distillation tower through the first discharge port.
[0013] Preferably, a second spray assembly is provided at the upper end of the interior of the catalytic distillation tower, and the first discharge port is connected to the liquid inlet end of the second spray assembly so as to spray the liquefied distillation gas output from the first discharge port into the interior of the catalytic distillation tower.
[0014] Preferably, the heating component in the catalytic distillation tower is arranged at the bottom of the tower.
[0015] It can be seen from the above technical scheme that the fractionation system of carbon four after ether provided by the embodiment of the utility model includes a catalytic distillation tower, a water cooling device, a reflux tank and a diverter. The catalytic distillation tower is used to fractionate the carbon four after ether transported in, and the solid phase MTBE produced is discharged from the solid phase outlet, and the liquefied distillation gas produced is discharged from the gas phase outlet. Then the liquefied distillation gas is cooled by the water cooling device so that it is not in a liquid phase state and transported to the reflux tank. Further, a part of the cooled liquefied distillation gas is discharged through the second discharge port of the diverter so that the methanol is extracted by the subsequent methanol extraction tower. At the same time, the first discharge port refluxes a part of the cooled liquefied distillation gas to the catalytic distillation tower to cool the interior of the catalytic distillation tower, thereby reducing the pressure in the distillation tower and improving the distillation efficiency of the distillation tower. It can be seen that the present scheme is to cool the liquefied distillation gas by water cooling, and its cooling effect is less affected by the ambient temperature, thereby improving the cooling effect. Moreover, this solution utilizes the cooled liquefied distillation gas to flow back into the catalytic distillation tower to cool the tower, and no new substances will be introduced into the tower. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 A schematic diagram of a post-ether C4 fractionation system provided in an embodiment of the utility model.
[0017] Figure 2 A schematic diagram of another post-ether C4 fractionation system provided in an embodiment of the utility model.
[0018] In the figure: etherification reactor 1, catalytic distillation tower 2, water cooling device 3, reflux tank 4, diversion device 5, MTBE collection equipment 6, first discharge port 7, second discharge port 8, methanol extraction tower 9, air cooling device 10, cooling tower 11, water pump 12, reflux pump 13, solenoid valve 14. DETAILED DESCRIPTION
[0019] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0020] See also Figure 1-2The embodiment of the utility model provides a fractionation system for C4 after etherification, and the fractionation system comprises: a catalytic distillation tower 2, a water cooling device 3, a reflux tank 4 and a diverter 5; the material inlet of the catalytic distillation tower 2 is connected with the material outlet of the etherification reactor 1, so as to transport the etherified C4 product in the etherification reactor 1 to the catalytic distillation tower 2, the solid phase outlet of the catalytic distillation tower 2 is connected with the MTBE collecting device 6, so as to collect the separated MTBE; the gas phase outlet of the catalytic distillation tower 2 is connected with the inlet of the water cooling device 3 The feed end is connected to the catalytic distillation tower 2 to cool the liquefied distillation gas produced by the catalytic distillation tower 2 through the water cooling device 3; the discharge end of the water cooling device 3 is connected to the feed end of the reflux tank 4, and the discharge end of the reflux tank 4 is connected to the feed end of the diverter device 5; the diverter device 5 includes a first discharge port 7 and a second discharge port 8, the first discharge port 7 is connected to the inside of the catalytic distillation tower 2, and is used to cool the inside of the catalytic distillation tower 2 using the cooled liquefied distillation gas; the second discharge port 8 is connected to the feed port of the subsequent methanol extraction tower 9.
[0021] In this embodiment, the products produced by the etherification reaction of methanol and C4 include MTBE, alkanes, excess methanol and C4, etc. After the products enter the catalytic distillation tower 2, the catalytic distillation tower 2 fractionates the products by heating, for example, it can be heated to 120 degrees Celsius. MTBE has a high boiling point and is still in liquid state at this temperature, so MTBE can be separated from the liquid phase outlet of the catalytic distillation tower 2. Others such as alkanes, excess methanol and C4 are in gas phase at this temperature, so they can be discharged from the gas phase outlet of the catalytic distillation tower 2. The mixed gas discharged from the gas phase outlet is called liquefied distillation gas. The liquefied distillation gas enters the cooling device and is cooled to liquid phase. The liquid phase liquefied distillation gas enters the reflux tank 4. The diverter 5 further returns a part of the liquid phase liquefied distillation gas to the catalytic distillation tower 2 through the first discharge port 7 to cool the catalytic distillation tower 2, thereby reducing the pressure in the tower and improving the fractionation efficiency of the catalytic distillation tower 2. A portion is discharged through the second discharge port 8, for example, it can be discharged into the methanol extraction tower 9 to extract methanol and further separate and collect the alkanes.
[0022] In one embodiment, the water cooling device 3 may be provided with a first spray assembly for spraying cooling water on the material flow pipeline to cool the liquefied distillation gas in the material pipeline. In this way, the liquefied distillation gas is quickly cooled into a liquid phase by spraying with cooling water.
[0023] Further, the fractionation system may also include an air cooling device 10, which is used to cool the cooling water in the water cooling device 3. In this embodiment, the cooling water in the water cooling device 3 may be circulating cooling water that is circulated in the water cooling device 3. The air cooling device 10 cools the circulating cooling water by air cooling. The cooled circulating cooling water is poured on the material circulation pipeline to cool the liquefied distillation gas. Further, the temperature of the cooling water after cooling the liquefied distillation gas increases. At this time, the cooling water with increased temperature is cooled by the air cooling device 10. In this cycle, the water cooling device 3 continuously cools the liquefied distillation gas.
[0024] For the water cooling device 3, in another embodiment, the cooling water may be produced water in the cooling tower 11. Specifically, the fractionation system may further be provided with a pumping pump 12, the water inlet end of the water cooling device 3 is connected to the water outlet end of the cooling tower 11, the water outlet end of the water cooling device 3 is connected to the water inlet end of the cooling tower 11, and the pumping pump 12 is provided on the pipeline between the water inlet end of the water cooling device 3 and the water outlet end of the cooling tower 11, and is used to extract cooling water in the cooling tower 11 to cool the liquefied distillation gas in the material flow pipeline.
[0025] In this embodiment, the cooling water in the cooling tower 11 is extracted in real time by the water pump 12 to serve as the cooling water of the water cooling device 3, thereby realizing the cooling of the liquefied distillation gas. Moreover, in this embodiment, the liquefied distillation gas is completely cooled by water cooling, which is less affected by the ambient temperature, thereby improving the cooling efficiency of the liquefied distillation gas, and further improving the cooling efficiency of the temperature in the catalytic distillation tower 2, effectively reducing the pressure in the catalytic distillation tower 2, and improving the fractionation efficiency of the catalytic distillation tower 2.
[0026] The flow dividing device 5 is used to return a portion of the cooled liquefied distillation gas to the catalytic distillation tower 2 through the first discharge port 7 to cool the catalytic distillation tower 2. Specifically, in one embodiment, a reflux pump 13 may be provided on the pipeline between the first discharge port 7 and the catalytic distillation tower 2 to transport the liquefied distillation gas output from the first discharge port 7 to the catalytic distillation tower 2. Since the liquefied distillation gas returned to the catalytic distillation tower 2 needs to be sprayed from the upper end of the tower, the substances in the tower can fully contact with the liquefied distillation gas with a lower temperature falling from the upper end, thereby realizing a rapid reduction in the temperature in the tower.
[0027] Furthermore, a solenoid valve 14 may be provided between the reflux pump 13 and the first discharge port 7, so that the solenoid valve 14 may be controlled according to actual conditions to meet different requirements. For example, when it is not necessary to return the cooled liquefied distillation gas to the catalytic distillation tower 2, the solenoid valve 14 is closed. For another example, the amount of the cooled liquefied distillation gas injected into the catalytic distillation tower 2 may be controlled by the solenoid valve 14 according to the actual temperature in the catalytic distillation tower 2.
[0028] Furthermore, in order to be able to control the amount of liquefied distillation gas returned to the catalytic distillation tower 2 from the first discharge port 7 according to actual conditions, the distillation system may also include a pressure monitoring device and a main control device, wherein the pressure monitoring device, the reflux pump 13 and the solenoid valve 14 are all electrically connected to the main control device; the pressure monitoring device is arranged on the catalytic distillation tower 2, and is used to monitor the pressure inside the catalytic distillation tower 2, and upload the monitored pressure data to the main control device; the main control device is used to control the reflux pump 13 and the solenoid valve 14 according to the received pressure data, so as to adjust the flow rate of the liquefied distillation gas entering the catalytic distillation tower 2 through the first discharge port 7.
[0029] In this embodiment, the fractionation system is also provided with a pressure monitoring device, which can monitor the pressure inside the catalytic distillation tower 2 in real time, and feed back the monitored pressure data to the main control device, so that the main control device can control the solenoid valve 14 according to the fed-back pressure data, thereby adjusting the amount of liquefied distillation gas entering the catalytic distillation tower 2 from the first discharge port 7. For example, the opening amount of the solenoid valve 14 corresponding to different pressure thresholds can be pre-configured. When the catalytic distillation tower 2 does not need to be cooled, the main control device controls the reflux pump 13 to stop working and controls the solenoid valve 14 to close. When the pressure in the catalytic distillation tower 2 is greater than the first preset threshold, the reflux pump 13 is controlled to open, and the solenoid valve 14 is controlled to open at the same time, and the opening amount of the solenoid valve 14 corresponds to the opening amount of the pre-configured first preset threshold. In this way, by monitoring the pressure in the tower in real time, the amount of liquefied distillation gas refluxed from the first discharge port 7 to the catalytic distillation tower 2 can be adjusted in real time, which can not only ensure the fractionation efficiency of the catalytic distillation tower 2, but also avoid redundant reflux of the liquefied distillation gas.
[0030] For the catalytic distillation tower 2, its heating assembly should be arranged at the bottom of the tower, and in order to ensure the cooling effect of the cooled liquefied distillation gas on the catalytic distillation tower 2, in one embodiment, a second spray assembly can be arranged at the upper end of the interior of the catalytic distillation tower 2, and the first discharge port 7 is connected to the liquid inlet end of the second spray assembly, so as to spray the liquefied distillation gas output from the first discharge port 7 into the interior of the catalytic distillation tower 2. For example, the second spray assembly can be composed of one or more spray heads, which are evenly distributed on the same plane in the tower to achieve uniform cooling of the tower.
[0031] The modules or units in the device of the embodiment of the utility model can be combined, divided and deleted according to actual needs. The above disclosure is only the preferred embodiment of the utility model, and of course it cannot be used to limit the scope of the rights of the utility model. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments are implemented, and equivalent changes made according to the claims of the utility model still fall within the scope of the utility model.
Claims
1. A fractionation system for post-etherification C4, characterized in that: The fractionation system comprises: a catalytic distillation tower, a water cooling device, a reflux tank and a diverter; the material inlet of the catalytic distillation tower is connected with the material outlet of the etherification reactor so as to transport the etherified C4 product in the etherification reactor to the catalytic distillation tower, and the liquid phase outlet of the catalytic distillation tower is connected with the MTBE collecting device so as to collect the separated MTBE; the gas phase outlet of the catalytic distillation tower is connected with the feed end of the water cooling device so as to cool the liquefied distillation gas generated by the catalytic distillation tower through the water cooling device; the discharge end of the water cooling device is connected with the feed end of the reflux tank, and the discharge end of the reflux tank is connected with the feed end of the diverter; the diverter comprises a first discharge port and a second discharge port, the first discharge port is connected with the inside of the catalytic distillation tower so as to cool the inside of the catalytic distillation tower by using the cooled liquefied distillation gas; the second discharge port is connected with the feed port of the subsequent methanol extraction tower.
2. The etherified C4 fractionation system according to claim 1, characterized in that: The water cooling device is provided with a first spray assembly for spraying cooling water on the material flow pipeline to cool the liquefied distillation gas in the material pipeline.
3. The fractionation system of post-ether C4 according to claim 2, characterized in that: The fractionation system also includes an air cooling device, which is used to cool the cooling water in the water cooling device.
4. The fractionation system of post-ether C4 according to claim 2, characterized in that: The distillation system is also provided with a water pump. The water inlet end of the water cooling device is connected to the water outlet end of the cooling tower, and the water outlet end of the water cooling device is connected to the water inlet end of the cooling tower. The water pump is arranged on the pipeline between the water inlet end of the water cooling device and the water outlet end of the cooling tower, and is used to extract cooling water in the cooling tower to cool the liquefied distillation gas in the material flow pipeline.
5. The etherified C4 fractionation system according to claim 1, characterized in that: A reflux pump is provided on the pipeline between the first discharge port and the catalytic distillation tower for conveying the liquefied distillation gas output from the first discharge port to the catalytic distillation tower.
6. The fractionation system of post-ether C4 according to claim 5, characterized in that: A solenoid valve is arranged between the reflux pump and the first discharge port.
7. The fractionation system of post-ether C4 according to claim 6, characterized in that: The distillation system also includes a pressure monitoring device and a main control device, wherein the pressure monitoring device, the reflux pump and the solenoid valve are all electrically connected to the main control device; the pressure monitoring device is arranged on the catalytic distillation tower, and is used to monitor the pressure inside the catalytic distillation tower, and upload the monitored pressure data to the main control device; the main control device is used to control the reflux pump and the solenoid valve according to the received pressure data, so as to adjust the flow rate of the liquefied distillation gas entering the catalytic distillation tower through the first discharge port.
8. The etherified C4 fractionation system according to claim 1, characterized in that: A second spray assembly is disposed at the upper end of the catalytic distillation tower, and the first discharge port is communicated with the liquid inlet end of the second spray assembly so as to spray the liquefied distillation gas output from the first discharge port into the interior of the catalytic distillation tower.
9. The fractionation system for post-ether C4 according to any one of claims 1 to 8, characterized in that: The heating component in the catalytic distillation tower is arranged at the bottom of the tower.