A crude methanol distillation system

Abstract

This utility model discloses a crude methanol distillation system, including an expansion tank. The outlet of the expansion tank is connected to the inlet of an intermediate tank via a first pipeline. The outlet of the intermediate tank is connected to a transfer pump group via a second pipeline. The outlet of the transfer pump group is connected to the inlet of a preheater via a third pipeline. The outlet of the preheater is connected to the inlet of a pre-distillation column via a fourth pipeline. The top outlet of the pre-distillation column's vapor phase is connected to the inlet of a first condenser via a fifth pipeline. The outlet of the first condenser is connected to the inlet of a second condenser. The outlet of the second condenser is connected to the inlet of a non-condensable vapor recovery column via a sixth pipeline. The outlet of the non-condensable vapor recovery column is connected to the first pipeline via a seventh pipeline. The transfer pump group includes two metering pumps and two feed pumps connected in parallel on the second pipeline. The advantages of this utility model are: by using parallel connections, it can effectively avoid power consumption during the crude methanol distillation system's transport process, reduce production costs, save electricity, and ensure stable system operation.

Description

Technical fields: This utility model relates to the field of methanol distillation technology, specifically a crude methanol distillation system. Background technology: Crude methanol distillation refers to the process of purifying crude methanol through distillation. Crude methanol is a direct product of the methanol synthesis reaction and typically contains impurities such as water, ethanol, dimethyl ether, and higher alcohols, making it unsuitable for direct use as a product. Crude methanol is pumped to a preheater for preheating, and then fed to a pre-distillation column. Utilizing the differences in volatility of the components, the pre-distillation column separates them through distillation. Through multiple vaporization and condensation processes, impurities are removed from the crude methanol, yielding highly purified methanol.

[0001] Depending on production demand, when production demand increases, the crude methanol distillation system can operate at full capacity due to the large amount of crude methanol, using a 90KW feed pump for delivery, consuming an average of about 2160 kWh of electricity per day. However, when production demand decreases, the amount of crude methanol decreases significantly, making it impossible for the crude methanol distillation system to operate at full capacity. If the 90KW feed pump continues to be used, it will result in wasted electricity and increased operating costs. Utility Model Content: The purpose of this invention is to provide a crude methanol distillation system to solve the problems mentioned in the background art.

[0002] This utility model is implemented by the following technical solution: A crude methanol distillation system includes an expansion tank. The outlet of the expansion tank is connected to the inlet of an intermediate tank via a first pipeline. The outlet of the intermediate tank is connected to a transfer pump group via a second pipeline. The outlet of the transfer pump group is connected to the inlet of a preheater via a third pipeline. The outlet of the preheater is connected to the inlet of a pre-distillation column via a fourth pipeline. The top vapor outlet of the pre-distillation column is connected to the inlet of a first condenser via a fifth pipeline. The outlet of the first condenser is connected to the inlet of a second condenser. The outlet of the second condenser is connected to the inlet of a non-condensable vapor recovery column via a sixth pipeline. The outlet of the non-condensable vapor recovery column is connected to the first pipeline via a seventh pipeline. The transfer pump group includes two metering pumps and two feed pumps connected in parallel on the second pipeline.

[0003] Preferably, the second pipeline is connected to the inlets of two metering pumps and two feed pumps respectively, and the outlets of the two metering pumps and two feed pumps are connected to the third pipeline respectively.

[0004] Preferably, the liquid bottom outlet of the pre-distillation column is connected to the inlet of the reboiler, and the outlet of the reboiler is connected to the inlet of the pre-distillation column.

[0005] The advantages of this invention are: by using a parallel connection, it can effectively avoid power consumption during the transportation process of the crude methanol distillation system, reduce production costs, save electricity, and ensure the stable operation of the system. Attached image description: Figure 1 This is a schematic diagram of the main structure of this utility model.

[0006] In the diagram: 1. Expansion tank; 2. First pipeline; 3. Intermediate tank; 4. Second pipeline; 5. Transfer pump set; 5.1. Metering pump; 5.2. Feed pump; 6. Third pipeline; 7. Preheater; 8. Fourth pipeline; 9. Pre-distillation column; 10. Fifth pipeline; 11. First condenser; 12. Second condenser; 13. Sixth pipeline; 14. Non-condensable vapor recovery column; 15. Seventh pipeline; 16. Reboiler. Detailed implementation method: The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0007] Please see Figure 1 This utility model provides a technical solution for a crude methanol distillation system: A crude methanol distillation system includes an expansion tank 1 containing synthesized crude methanol. The outlet of the expansion tank 1 is connected to the inlet of an intermediate tank 3 via a first pipeline 2, temporarily storing the synthesized crude methanol in the intermediate tank 3. The outlet of the intermediate tank 3 is connected to a transfer pump assembly 5 via a second pipeline 4. The transfer pump assembly 5 includes two metering pumps 5.1 and two feed pumps 5.2 connected in parallel to the second pipeline 4. The second pipeline 4 is connected to the inlets of the two metering pumps 5.1 and the two feed pumps 5.2, respectively. The outlets of the two metering pumps 5.1 and the two feed pumps 5.2 are connected to a third pipeline 6, respectively.

[0008] When the crude methanol distillation system can operate at full load, close the valves on both sides of the 3KW metering pump 5.1, open the valves on both sides of the feed pump 5.2, and use the 90KW feed pump 5.2 to transport crude methanol.

[0009] When production demand decreases, the amount of crude methanol decreases significantly, making it impossible for the crude methanol distillation system to operate at full capacity. At this time, the valves on both sides of the 90KW feed pump 5.2 are closed, and the valves on both sides of the metering pump 5.1 are opened. The 3KW metering pump 5.1 is used to transport crude methanol, thereby avoiding the waste of electricity and reducing cost expenditures.

[0010] The outlet of the transfer pump unit 5 is connected to the inlet of the preheater 7 via the third pipeline 6. The crude methanol is preheated by the preheater 7. The outlet of the preheater 7 is connected to the inlet of the pre-distillation column 9 via the fourth pipeline 8. The preheated crude methanol is sent into the pre-distillation column 9 for distillation. The top outlet of the vapor phase of the pre-distillation column 9 is connected to the inlet of the first condenser 11 via the fifth pipeline 10. The outlet of the first condenser 11 is connected to the inlet of the second condenser 12. The distilled methanol is condensed twice to obtain high-purity methanol. The outlet of the second condenser 12 is connected to the inlet of the non-condensable vapor recovery column 14 via the sixth pipeline 13. The non-condensable vapor recovery column 14 recovers the uncondensed non-condensable vapor. The outlet of the non-condensable vapor recovery column 14 is connected to the first pipeline 2 via the seventh pipeline 15. The recovered non-condensable vapor contains a small amount of crude methanol that is not collected. It is reconnected to the first pipeline 2 and flows into the intermediate tank 3 to continue the distillation process.

[0011] The liquid bottom outlet of the pre-distillation column 9 is connected to the inlet of the reboiler 16, and the outlet of the reboiler 16 is connected to the inlet of the pre-distillation column 9.

[0012] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A crude methanol distillation system, characterized in that: The system includes an expansion tank (1), the outlet of which is connected to the inlet of an intermediate tank (3) via a first pipeline (2), the outlet of which is connected to a transfer pump group (5) via a second pipeline (4), the outlet of which is connected to the inlet of a preheater (7) via a third pipeline (6), the outlet of which is connected to the inlet of a pre-distillation column (9) via a fourth pipeline (8), and the top vapor outlet of the pre-distillation column (9) is connected to a first refrigeration unit via a fifth pipeline (10). The inlet of the condenser (11) is connected, the outlet of the first condenser (11) is connected to the inlet of the second condenser (12), the outlet of the second condenser (12) is connected to the inlet of the non-condensable steam recovery tower (14) through the sixth pipeline (13), and the outlet of the non-condensable steam recovery tower (14) is connected to the first pipeline (2) through the seventh pipeline (15); the delivery pump group (5) includes two metering pumps (5.1) and two feed pumps (5.2) connected in parallel on the second pipeline (4).

2. The crude methanol distillation system according to claim 1, characterized in that: The second pipeline (4) is connected to the inlets of two metering pumps (5.1) and two feed pumps (5.2) respectively, and the outlets of the two metering pumps (5.1) and two feed pumps (5.2) are connected to the third pipeline (6) respectively.

3. The crude methanol distillation system according to claim 1, characterized in that: The liquid bottom outlet of the pre-distillation column (9) is connected to the inlet of the reboiler (16), and the outlet of the reboiler (16) is connected to the inlet of the pre-distillation column (9).

Images