Complete rectification device for high-purity hexane

Abstract

The utility model relates to a complete rectification device for high-purity hexane, which comprises a liquid separation tank, an upper dehydrating tower and a lower dehydrating tower which are sequentially communicated, and is technically characterized in that a plurality of horizontal liquid outlet pipelines are sequentially arranged at the lower part of the liquid separation tank from top to bottom, and the tail ends of the horizontal liquid outlet pipelines are communicated through a confluence pipeline; an outlet of the confluence pipeline is connected with an inlet pipeline of a lifting pump, the tail end of an outlet pipeline of the lifting pump is connected with a liquid inlet in the upper part of the upper tower of the dehydrating tower, each horizontal liquid outlet pipeline is sequentially provided with a front control valve and a rear control valve, and the horizontal liquid outlet pipeline is provided with a sampling branch between the front control valve and the rear control valve; a sampling valve is arranged on the sampling branch, an inner extension section extending to the bottom surface of the liquid separation tank is arranged at the inner end of the lowest horizontal liquid outlet pipeline, and a liquid discharge valve is arranged on an inlet pipeline of the lifting pump. The device is beneficial to understanding the solution concentration distribution condition in the liquid separation tank, is beneficial to adjusting the liquid outlet height of the liquid separation tank according to the layering condition in the liquid separation tank, and reduces the energy consumption of the lifting pump.

Description

Technical Field

[0001] The utility model relates to chemical equipment, in particular to a high-purity hexane complete distillation device. Background Art

[0002] At present, a distillation tower and a cooling device are generally used to distill high-purity hexane from a hexane aqueous solution. CN205024118 U discloses a high-purity hexane complete distillation device, which includes a washing tower, a separator, an upper tower of a dehydration tower, and a lower tower of a dehydration tower connected in sequence, and the gas outlet at the top of the upper tower of the dehydration tower is connected to the inlet of the separator through a condenser and a cooler in sequence. The device obtains high-purity refined hexane in the tower kettle through the azeotropy of water and hexane, and the azeotropy of water and hexane at the top of the tower is returned to the separator after condensation and cooling to mix with the hexane aqueous solution of the raw material, and after cyclic dehydration, the hexane loss is reduced and the recovery rate of hexane is improved. However, there are still the following problems when using it: the outlet pipeline position of the separator is fixed, which is not conducive to adjusting the liquid outlet position according to the liquid separation situation. Utility Model Content

[0003] The purpose of the utility model is to provide a high-purity hexane complete distillation device with a reasonable structure and reliable use to solve the above-mentioned problems, which is conducive to understanding the concentration distribution of the solution in the separator tank, adjusting the liquid outlet height of the separator tank according to the stratification situation in the separator tank, and reducing the energy consumption of the lifting pump.

[0004] The technical solution of the utility model is:

[0005] A high-purity hexane complete distillation device comprises a liquid separator, an upper tower of a dehydration tower and a lower tower of a dehydration tower which are connected in sequence, a condenser and a cooler are connected in sequence between the top of the upper tower of the dehydration tower and the gas outlet at the top of the liquid separator, a reboiler is further connected to the lower part of the lower tower of the dehydration tower, and a hexane liquid outlet is arranged at the bottom of the lower tower of the dehydration tower. The technical key points are: a plurality of horizontal liquid outlet pipes are arranged in sequence from top to bottom at the lower part of the liquid separator, the ends of the horizontal liquid outlet pipes are connected by a converging pipe, the outlet of the converging pipe is connected to the inlet pipe of a lifting pump, the end of the outlet pipe of the lifting pump is connected to the upper liquid inlet of the upper tower of the dehydration tower, each horizontal liquid outlet pipe is arranged in sequence with a front control valve and a rear control valve, a sampling branch is arranged at the position between the front control valve and the rear control valve, a sampling valve is arranged on the sampling branch, an inner end of the lowest horizontal liquid outlet pipe is arranged with an inner extension section extending to the bottom surface of the liquid separator, and a drain valve is arranged on the inlet pipe of the lifting pump.

[0006] In the above-mentioned high-purity hexane complete distillation device, an external drainage pipe is provided at the lower part of the upper tower of the dehydration tower, a pressure pump is provided at the end of the external drainage pipe, the end of the outlet pipe of the pressure pump is connected to the upper liquid inlet of the lower tower of the dehydration tower, and the vapor outlet at the top of the lower tower of the dehydration tower is connected to the vapor inlet of the upper tower of the dehydration tower by a pipeline.

[0007] In the above-mentioned high-purity hexane complete distillation device, an inclined support plate is provided on the outer side of the inner port of the inner extension section, the inclined support plate is fixed to the bottom of the liquid separator tank, and a filter screen corresponding to the inner port of the inner extension section is provided on the lower surface of the inclined support plate.

[0008] In the above-mentioned high-purity hexane complete distillation device, the sampling valve outlet on the sampling branch is connected to the sampling bin, a concentration detection sensor is provided in the sampling bin, a drain valve is provided at the bottom of the sampling bin, the drain valve outlet is connected to the top of the buffer tank by a pipeline, a recovery pipeline is provided in the buffer tank, the lower end of the recovery pipeline is close to the bottom of the tank, the upper end leads out of the buffer tank and intersects with the inlet pipe of the lifting pump, and a recovery valve is provided at the upper end of the recovery pipeline.

[0009] The beneficial effects of the utility model are:

[0010] The liquid outlet height of the liquid separator tank is switched by using each horizontal liquid outlet pipe. Specifically, the front control valve, the rear control valve and the sampling valve on the sampling branch line on the horizontal liquid outlet pipe are used to take samples. When the sample concentration is found to be lower than the set value, another horizontal liquid outlet pipe is switched downward to discharge the liquid. Since the lift pump can reduce the output power according to the sampling signal when the horizontal liquid outlet pipe is at a higher position, it does not need to maintain high power output for a long time, thereby reducing the energy consumption of the lift pump as a whole. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of the utility model;

[0012] Figure 2 yes Figure 1 A partial schematic diagram of

[0013] Figure 3 yes Figure 2 Schematic diagram of a horizontal liquid outlet pipeline, sampling branch and peripheral components.

[0014] In the figure: 1. liquid separator, 2. cooler, 3. condenser, 4. upper tower of dehydration tower, 5. lower tower of dehydration tower, 6. gas outlet, 7. gas inlet, 8. booster pump, 9. reboiler, 10. lift pump, 11. drain valve, 12. confluence pipe, 13. horizontal liquid outlet pipe, 14. inner extension section, 15. front control valve, 16. rear control valve, 17. sampling valve, 18. sampling branch, 19. inclined support plate, 20. sampling chamber, 21. concentration detection sensor, 22. drain valve, 23. buffer tank, 24. recovery pipeline, 25. recovery valve. DETAILED DESCRIPTION

[0015] The utility model is described in detail according to the accompanying drawings of the specification.

[0016] like Figure 1 to Figure 3As shown, the high-purity hexane complete distillation device comprises a liquid separator 1, an upper dehydration tower 4 and a lower dehydration tower 5 which are connected in sequence. A condenser 3 and a cooler 2 are connected in sequence between the top of the upper dehydration tower 4 and the gas outlet at the top of the liquid separator 1, a reboiler 9 is further connected to the lower part of the lower dehydration tower 5, and a hexane liquid outlet is arranged at the bottom of the lower dehydration tower 5. An external drainage pipe is arranged at the lower part of the upper dehydration tower 4, a booster pump 8 is arranged at the end of the external drainage pipe, the outlet pipe end of the booster pump 8 is connected to the upper liquid inlet of the lower dehydration tower 5, and the gas outlet 6 at the top of the lower dehydration tower 5 is connected to the gas inlet 7 of the upper dehydration tower 4 by a pipeline.

[0017] The lower part of the liquid separation tank 1 is provided with a plurality of horizontal liquid outlet pipes 13 from top to bottom, and the ends of the horizontal liquid outlet pipes 13 are connected by a confluence pipe 12, and the outlet of the confluence pipe 12 is connected to the inlet pipe of the lift pump 10, and the outlet pipe end of the lift pump 10 is connected to the upper liquid inlet of the upper tower 4 of the dehydration tower. A front control valve 15 and a rear control valve 16 are provided on each horizontal liquid outlet pipe 13 in sequence, and a sampling branch 18 is provided on the horizontal liquid outlet pipe 13 at a position between the front control valve 15 and the rear control valve 16, and a sampling valve 17 is provided on the sampling branch 18, and an inner extension section 14 extending toward the bottom surface of the liquid separation tank 1 is provided at the inner end of the lowest horizontal liquid outlet pipe 13, and a drain valve 11 is provided on the inlet pipe of the lift pump 10.

[0018] In this embodiment, an oblique support plate 19 is provided on the outer side of the inner port of the inner extension section 14, and the oblique support plate 19 is fixed to the bottom of the liquid separation tank 1. The lower surface of the oblique support plate 19 is provided with a filter screen (not shown in the figure) corresponding to the inner port of the inner extension section 14 to prevent solid impurities generated by the previous process from entering the subsequent equipment. The outlet of each sampling valve 17 on the sampling branch 18 is connected to the sampling bin 20, and a concentration detection sensor 21 is provided in the sampling bin 20. A drain valve 22 is provided at the bottom of the sampling bin 20. The outlet of the drain valve 22 is connected to the top of the buffer tank 23 by a pipeline. A recovery pipeline 24 is provided in the buffer tank 23. The lower end of the recovery pipeline 24 is close to the bottom of the tank, and the upper end leads out of the buffer tank 23 and intersects with the inlet pipeline of the lift pump 10. A recovery valve 25 is provided at the upper end of the recovery pipeline 24.

[0019] Working principle:

[0020] During operation, the front control valve 15 on the highest horizontal liquid outlet pipe 13 is first opened, and then the front control valve 15 is closed. Then, the sampling valve 17 on the sampling branch 18 connected thereto is opened, so that the sampled liquid entering the horizontal liquid outlet pipe 13 between the front and rear control valves falls into the sampling bin 20, and the sampling valve 17 is closed. The concentration of the hexane aqueous solution of the sampled liquid is detected by the concentration detection sensor 21. When the concentration of the hexane aqueous solution is high, the front and rear control valves and the drain valve 11 are opened, and the lifting pump 10 is started. The liquid in the liquid separator 1 enters the upper tower 4 of the dehydration tower through the highest horizontal liquid outlet pipe 13, the confluence pipe 12 and the lifting pump 10 for distillation operation.

[0021] After the set time, close the lifting pump 10 and the rear control valve 16 on the highest horizontal liquid outlet pipe 13, then close the front control valve 15, open the sampling valve 17, so that the sampling liquid entering the horizontal liquid outlet pipe 13 between the front and rear control valves falls into the sampling chamber 20, and use the concentration detection sensor 21 to detect the hexane aqueous solution concentration of the sampling liquid again. When it is found that the sampling concentration is lower than the set value, open the front and rear control valves on the next horizontal liquid outlet pipe adjacent to the highest horizontal liquid outlet pipe 13, close the front and rear control valves on the highest horizontal liquid outlet pipe 13, and the liquid in the separator tank 1 enters the upper tower 4 of the dehydration tower via the next horizontal liquid outlet pipe 13, the confluence pipe 12 and the lifting pump 10 for distillation operation.

[0022] By analogy, the liquid in the liquid separator 1 finally enters the upper tower of the dehydration tower through the lowest horizontal liquid outlet pipe 13, the confluence pipe 12 and the lifting pump 10 for distillation operation. The sampled liquid accumulated in the buffer tank 23 can be introduced into the upper tower 4 of the dehydration tower by the lifting pump 10 for distillation operation.

[0023] The above is a detailed description of the embodiments of the utility model, but the above contents are only preferred embodiments of the utility model and cannot be considered to limit the scope of implementation of the utility model. All equivalent changes and improvements made within the scope of the invention of the utility model should still fall within the scope of this patent.

Claims

1. A high-purity hexane complete distillation device, comprising a separator, an upper dehydration tower and a lower dehydration tower connected in sequence, a condenser and a cooler are connected in sequence between the top of the upper dehydration tower and the gas outlet at the top of the separator, a reboiler is further connected to the lower part of the lower dehydration tower, and a hexane liquid outlet is provided at the bottom of the lower dehydration tower, characterized in that: The lower part of the liquid separation tank is provided with a plurality of horizontal liquid outlet pipes from top to bottom, and the ends of the horizontal liquid outlet pipes are connected by a converging pipe, the outlet of the converging pipe is connected to the inlet pipe of the lifting pump, and the end of the outlet pipe of the lifting pump is connected to the upper liquid inlet of the upper tower of the dehydration tower, and each horizontal liquid outlet pipe is provided with a front control valve and a rear control valve in sequence, and a sampling branch is provided on the horizontal liquid outlet pipe at a position between the front control valve and the rear control valve, and a sampling valve is provided on the sampling branch, and an inner extension section extending to the bottom surface of the liquid separation tank is provided at the inner end of the lowest horizontal liquid outlet pipe, and a drain valve is provided on the inlet pipe of the lifting pump.

2. The high-purity hexane complete distillation device according to claim 1, characterized in that: An external drainage pipe is provided at the lower part of the upper tower of the dehydration tower, a pressure pump is provided at the end of the external drainage pipe, the end of the outlet pipe of the pressure pump is connected to the upper liquid inlet of the lower tower of the dehydration tower, and the steam outlet at the top of the lower tower of the dehydration tower is connected to the steam inlet of the upper tower of the dehydration tower by a pipeline.

3. The high-purity hexane complete distillation device according to claim 1, characterized in that: An oblique support plate is provided on the outer side of the inner port of the inner extension section, and the oblique support plate is fixed to the bottom of the liquid separation tank. A filter screen corresponding to the inner port of the inner extension section is provided on the lower surface of the oblique support plate.

4. The high-purity hexane complete distillation device according to claim 1, characterized in that: The sampling valve outlet on the sampling branch is connected to the sampling bin, a concentration detection sensor is provided in the sampling bin, a drain valve is provided at the bottom of the sampling bin, the outlet of the drain valve is connected to the top of the buffer tank by a pipeline, a recovery pipeline is provided in the buffer tank, the lower end of the recovery pipeline is close to the bottom of the tank, the upper end leads out of the buffer tank and intersects with the inlet pipe of the lifting pump, and a recovery valve is provided at the upper end of the recovery pipeline.

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