Feeding system for isomerization reaction of aromatic hydrocarbon combination unit
By introducing a liquid-phase isomerization reaction unit into the aromatics complex and connecting it in parallel with the gas-phase isomerization unit, the problem of high energy consumption was solved, and energy consumption was reduced while processing capacity was improved.
Patent Information
- Application Number
- CN202423256810.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-29
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2034-12-29
AI Technical Summary
The isomerization reaction in aromatic hydrocarbon complexes is energy-intensive and requires extensive air cooling, making it difficult for existing technologies to effectively reduce energy costs.
A liquid-phase isomerization reaction unit is introduced into the aromatics complex and connected in parallel with the gas-phase isomerization unit. The liquid-phase isomerization process treats part of the feedstock, thereby reducing the gas-phase isomerization load.
While maintaining PX production at a basically unchanged level, the plant reduced energy costs and increased processing capacity, which is beneficial to the plant's capacity expansion needs.
Smart Images
Figure CN223780194U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of isomerization reaction in aromatic hydrocarbon complexes, specifically to a feeding system for isomerization reaction in aromatic hydrocarbon complexes, belonging to the petrochemical field. Background Technology
[0002] The isomerization reaction in the aromatic hydrocarbon complex, as the main unit for PX production, is characterized by high temperature and pressure, requiring a large amount of heat and extensive air cooling after the reaction. Therefore, the energy consumption in the PX production process is relatively high. Utility Model Content
[0003] In view of the defects of the prior art, the purpose of this utility model is to provide an isomerization reaction feeding system for an aromatic hydrocarbon complex, which is connected in parallel with gas phase isomerization to increase liquid phase isomerization, thereby effectively reducing the gas phase isomerization load and thus reducing energy consumption costs.
[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: an isomerization reaction feeding system for an aromatic hydrocarbon complex, comprising an isomerization feed main, a gas-phase isomerization unit, and a liquid-phase isomerization unit. The outlet of the isomerization feed main is connected to a gas-phase isomerization feed line and a liquid-phase isomerization feed line. The gas-phase isomerization feed line is connected to the gas-phase isomerization unit. The liquid-phase isomerization feed line is connected to the liquid-phase isomerization unit. The liquid-phase isomerization unit includes a liquid-phase isomerization feed-product heat exchanger, a steam heat exchanger, and a liquid-phase isomerization reactor. The liquid-phase isomerization feed line is sequentially connected to the liquid-phase isomerization feed-product heat exchanger and the steam heat exchanger before being connected to the inlet of the liquid-phase isomerization reactor. The outlet of the liquid-phase isomerization reactor is connected to a liquid-phase isomerization reactor outlet line. The liquid-phase isomerization reactor outlet line is connected to the liquid-phase isomerization feed-product heat exchanger for heat exchange before being connected to a xylene separation unit.
[0005] Furthermore, the gas phase isomerization unit includes a gas phase isomerization feed heat exchanger, a plate heat exchanger, a heating furnace, a gas phase isomerization reactor, an air cooler, a high-precision separator, and a deheptane tower. The gas phase isomerization feed pipeline is connected in sequence to the gas phase isomerization feed heat exchanger, the plate heat exchanger, and the heating furnace, and then connected to the inlet of the gas phase isomerization reactor. The outlet of the gas phase isomerization reactor is connected to the gas phase isomerization reactor outlet pipeline. The gas phase isomerization reactor outlet pipeline is connected in sequence to the plate heat exchanger, the air cooler, the high-precision separator, and the deheptane tower. The bottom outlet of the deheptane tower is connected to the xylene separation unit through the bottom outlet pipeline of the deheptane tower.
[0006] Furthermore, the top of the high-precision tank is connected to a high-precision tank exhaust pipeline, which is connected to the fuel gas pipeline network.
[0007] Furthermore, the top of the heptane removal tower is connected to a gas phase outlet pipeline of the heptane removal tower, which is connected to the pentane removal tower.
[0008] Furthermore, a gas phase isomerization feed flow control valve is installed at the inlet of the gas phase isomerization feed line; a liquid phase isomerization feed flow control valve is installed at the inlet of the liquid phase isomerization feed line.
[0009] Furthermore, the isomerization reaction feeding system of the aromatics complex also includes an isomerization feed buffer tank and an isomerization feed pump. The bottom outlet of the isomerization feed buffer tank is connected to the isomerization feed main pipe, and the isomerization feed pump is connected to the isomerization feed main pipe. The gas phase isomerization feed line and the liquid phase isomerization feed line are connected to the outlet of the isomerization feed pump.
[0010] The beneficial effects of this invention are as follows: by increasing the liquid-phase isomerization reaction, the liquid-phase isomerization reaction can process part of the isomerization reaction feedstock, which can effectively reduce the isomerization gas-phase reaction load while maintaining the PX production at a basically unchanged level, thereby reducing the energy consumption cost of the device and increasing the processing capacity of the device, which is beneficial to the future expansion needs of the device. Attached Figure Description
[0011] Figure 1 Schematic diagram of the feeding system for the isomerization reaction in an aromatics complex;
[0012] In the diagram: 1. Isomerization feed buffer tank; 2. Isomerization feed pump; 3. Isomerization feed main; 4. Gas-phase isomerization feed line; 5. Liquid-phase isomerization feed line; 6. Liquid-phase isomerization feed-product heat exchanger; 7. Steam heat exchanger; 8. Liquid-phase isomerization reactor; 9. Liquid-phase isomerization reactor outlet line; 10. Gas-phase isomerization feed heat exchanger; 11. Plate heat exchanger; 12. Heating furnace; 13. Gas-phase isomerization reactor; 14. Air cooler; 15. High-precision separator; 16. Heptane removal tower; 17. Gas-phase isomerization reactor outlet line; 18. Heptane removal tower bottom outlet line; 19. Heptane removal tower gas phase outlet line; 20. High-precision separator exhaust line; 21. Gas-phase isomerization feed flow control valve. 22. Liquid phase isomerization feed flow control valve. Detailed Implementation
[0013] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.
[0014] See appendix Figure 1 The isomerization reaction feed system of the aromatics complex includes an isomerization feed manifold 3, a gas-phase isomerization unit, and a liquid-phase isomerization unit. A gas-phase isomerization feed line 4 and a liquid-phase isomerization feed line 5 are connected to the outlet of the isomerization feed manifold 3. The gas-phase isomerization feed line 4 is connected to the gas-phase isomerization unit. A gas-phase isomerization feed flow control valve 21 is installed at the inlet of the gas-phase isomerization feed line 4. The liquid-phase isomerization feed line 5 is connected to the liquid-phase isomerization unit, and a liquid phase isomerization feed line 5 is installed at the inlet of the liquid-phase isomerization feed line 5. The isomerization feed flow control valve 22 is used. The liquid phase isomerization unit includes a liquid phase isomerization feed-product heat exchanger 6, a steam heat exchanger 7, and a liquid phase isomerization reactor 8. The liquid phase isomerization feed line 5 is connected in sequence to the liquid phase isomerization feed-product heat exchanger 6 and the steam heat exchanger, and then 7 is connected to the inlet of the liquid phase isomerization reactor 8. The outlet of the liquid phase isomerization reactor 8 is connected to the liquid phase isomerization reactor outlet line 9. The liquid phase isomerization reactor outlet line 9 is connected to the liquid phase isomerization feed-product heat exchanger 6 for heat exchange and then connected to the xylene separation unit.
[0015] Further, the gas-phase isomerization unit includes a gas-phase isomerization feed heat exchanger 10, a plate heat exchanger 11, a heater 12, a gas-phase isomerization reactor 13, an air cooler 14, a high-precision separator 15, and a heptane removal tower 16; the gas-phase isomerization feed pipeline 4 is sequentially connected to the gas-phase isomerization feed heat exchanger 10, the plate heat exchanger 11, and the heater 12, and then connected to the inlet of the gas-phase isomerization reactor 13; the outlet of the gas-phase isomerization reactor 13 is connected to... There is a gas phase isomerization reactor outlet pipeline 17, which is sequentially connected to the plate heat exchanger 11, air cooler 14, high-precision separator 15 and deheptane tower 16. The bottom outlet of the deheptane tower 16 is connected to the xylene separation unit through the deheptane tower bottom outlet pipeline 18. The top of the deheptane tower 16 is connected to the deheptane tower gas phase outlet pipeline 19, which is connected to the depentane tower.
[0016] Furthermore, the top of the high-precision tank 15 is connected to a high-precision tank exhaust pipe 20, which is connected to the fuel gas pipeline network.
[0017] Furthermore, the isomerization reaction feeding system of the aromatics complex also includes an isomerization feed buffer tank 1 and an isomerization feed pump 2. The bottom outlet of the isomerization feed buffer tank 1 is connected to the isomerization feed main pipe 3, and the isomerization feed pump 2 is connected to the isomerization feed main pipe 3. The gas phase isomerization feed line 4 and the liquid phase isomerization feed line 5 are connected to the outlet of the isomerization feed pump 2.
[0018] In this embodiment, a liquid-phase isomerization branch process is added at the outlet of the isomerization feed pump 2 to the original gas-phase isomerization process. After exchanging heat with the liquid-phase isomerization reaction products, the liquid-phase isomerization feed is heated by steam in the steam heat exchanger 7 to reach the controlled temperature and then enters the newly added liquid-phase isomerization reactor 8. After the reaction, it can directly enter the xylene splitting unit.
[0019] The temperature for liquid-phase isomerization is generally 90-150℃, while the temperature for gas-phase isomerization is 300-500℃. Liquid-phase isomerization has a significantly lower temperature than gas-phase isomerization, so xylene loss is negligible, and ethylbenzene (EB) does not convert. Therefore, after the reaction, no gas-liquid separation or subsequent distillation is required; the xylene can be directly fed into the xylene splitting unit and then directly into the adsorption separation unit as a xylene feedstock.
[0020] Adding liquid-phase isomerization in parallel with the existing gas-phase isomerization process allows the liquid-phase isomerization reaction to handle part of the isomerization reaction feedstock. This effectively reduces the gas-phase isomerization load while maintaining a relatively constant PX production rate, thereby reducing energy consumption costs. Furthermore, it can increase the processing capacity of the unit, which is beneficial for future capacity expansion needs.
[0021] The advantages of liquid-phase isomerization are: the reaction uses liquid feed, no hydrogenation is required, there are fewer side reactions, and no distillation column separation is needed after the reaction, allowing direct use as a downstream product. The disadvantages are: compared to the original gas-phase isomerization, there is no ethylbenzene alkylation reaction, and it cannot remove ethylbenzene from the system. Therefore, liquid-phase isomerization is used as an energy-saving method to ensure normal system operation and as a modification measure to expand equipment capacity. It requires less investment, is simple to construct, and can also save energy and reduce consumption.
[0022] It should be noted that the parts of this utility model not described in detail are existing technologies.
[0023] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0024] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0025] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.
[0026] The above-listed embodiments are merely preferred embodiments of this utility model. Obviously, this utility model is not limited to the above embodiments and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of this utility model should be considered within the protection scope of this utility model.
Claims
1. An aromatics complex isomerization reaction feed system, characterized in that: The isomerization feed total pipe, the gas phase isomerization unit and the liquid phase isomerization unit, the gas phase isomerization feed pipe line is connected to the gas phase isomerization unit on the outlet of the isomerization feed total pipe and the liquid phase isomerization feed pipe line; The liquid phase isomerization feed pipe line is connected to the liquid phase isomerization unit, the liquid phase isomerization unit includes liquid phase isomerization feed-product heat exchanger, steam heat exchanger and liquid phase isomerization reactor, the liquid phase isomerization feed pipe line is connected to the inlet of the liquid phase isomerization reactor after being connected to the liquid phase isomerization feed-product heat exchanger and the steam heat exchanger in turn, the outlet of the liquid phase isomerization reactor is connected with the liquid phase isomerization reactor outlet pipe line, and the liquid phase isomerization reactor outlet pipe line is connected to the xylene separation unit after being heat exchanged in the liquid phase isomerization feed-product heat exchanger.
2. The aromatics complex isomerization reaction charging system according to claim 1, characterized in that: The gas phase isomerization unit includes gas phase isomerization feed heat exchanger, plate heat exchanger, heating furnace, gas phase isomerization reactor, air cooler, high separation tank and deheptane column; the gas phase isomerization feed pipe line is connected to the inlet of the gas phase isomerization reactor after being connected to the gas phase isomerization feed heat exchanger, plate heat exchanger and heating furnace in turn, the outlet of the gas phase isomerization reactor is connected with the gas phase isomerization reactor outlet pipe line, and the gas phase isomerization reactor outlet pipe line is connected to the plate heat exchanger, air cooler, high separation tank and deheptane column in turn, and the bottom outlet of the deheptane column is connected to the xylene separation unit through the deheptane column bottom outlet pipe line.
3. The aromatics complex isomerization reaction charging system according to claim 2, characterized in that: The top of the high separation tank is connected with the high separation tank exhaust pipe line, and the high separation tank exhaust pipe line is connected to the fuel gas pipe network.
4. The aromatics complex isomerization reaction charging system of claim 2, wherein: The top of the deheptane column is connected with the deheptane column gas phase outlet pipe line, and the deheptane column gas phase outlet pipe line is connected to the de-pentane column.
5. The aromatics complex isomerization reaction charging system according to any one of claims 1-4, characterized in that: The gas phase isomerization feed pipe line is provided with a gas phase isomerization feed flow control valve at the inlet, and the liquid phase isomerization feed pipe line is provided with a liquid phase isomerization feed flow control valve at the inlet.
6. The aromatics complex isomerization reaction charging system according to any one of claims 1-4, characterized in that: The isomerization feed buffer tank and the isomerization feed pump are further included, the isomerization feed total pipe is connected to the bottom outlet of the isomerization feed buffer tank, the isomerization feed total pipe is connected with the isomerization feed pump, and the gas phase isomerization feed pipe line and the liquid phase isomerization feed pipe line are connected to the outlet of the isomerization feed pump.