Separating device for recovering high-purity n-hexane

Abstract

The utility model relates to a separation device for recovering high-purity n-hexane, which comprises a distillation unit and a condensation unit, and feed is distilled and separated through each distillation cavity of a vertical distillation box in sequence from top to bottom. After being heated and evaporated in the distillation cavity, crude n-hexane steam sequentially passes through an upper vent hole in the upper part of the corresponding concentric heat insulation cylinder and a lower vent hole of the condensation vertical cylinder, enters the condensation vertical cylinder, is cooled by the pre-cooled concentric condensation vertical pipe and is condensed into liquid, and the liquid drops into a liquid receiving hopper; and finally, the high-purity hexane steam distilled by all the distillation cavities is condensed into liquid in a sealing head at the bottom of the condensation vertical cylinder, and the liquid can be discharged through a liquid collection outlet. In the whole process, a condensation path is prolonged, steam is prevented from being short-circuited to the last distillation cavity before being condensed and fully participates in repeated distillation separation of a plurality of distillation cavities, the separation effect is remarkably enhanced, and the product purity of n-hexane is remarkably improved.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical equipment, in particular to a separation device for recovering high-purity normal hexane. Background Art

[0002] At present, n-hexane, as a non-polar organic solvent, is mainly used as a solvent for the polymerization of olefins such as propylene, an extractant for edible vegetable oils, a solvent for rubber and coatings, and a dilution for pigments. In traditional processes, high-purity n-hexane is generally recovered by distillation.

[0003] CN 211659289 U discloses a separation device for recovering high-purity n-hexane, which comprises a distillation chamber and a condensation box, wherein the interior of the distillation chamber is divided into a plurality of heating chambers by partitions. In the separation device, PTC heaters are respectively installed on the bottom surfaces of the plurality of heating chambers of the distillation chamber, and the heating chamber corresponding to the liquid inlet pipe can be heated at a constant temperature by turning on the PTC heater through the control panel, and the volatilized steam enters the condensation box from the distillation chamber through the through holes on the surface of the liquid collecting plate, and the n-hexane mist is rapidly condensed into liquid under the action of the condensation column on the bottom surface of the condensation box and the coolant in the coolant chamber, and then drips into the liquid guide groove on the top surface of the liquid collecting plate, and the crude n-hexane in the liquid guide groove flows into the next heating chamber through the liquid discharge pipe. The separation device is intended to improve the distillation efficiency by using a method of repeated distillation of multiple heating chambers. However, the following problems still exist during use: a condensation column is arranged on the bottom of the condensation box to contact with the n-hexane vapor to conduct cold, and the condensation efficiency is low. The n-hexane vapor generated in the heating chamber at the front position can easily enter the heating chamber at the rear position through the drain pipe before condensation, and does not participate in repeated distillation. Utility Model Content

[0004] The utility model aims to provide a separation device for recovering high-purity n-hexane with reasonable structure and reliable use to solve the above problems, and through repeated distillation, the separation effect is significantly enhanced and the purity of the n-hexane product is improved.

[0005] The technical solution of the utility model is:

[0006] A separation device for recovering high-purity normal hexane, comprising a distillation unit and a condensation unit, the technical key points of which are: the distillation unit comprises a vertical distillation box, a plurality of distillation chambers arranged in the vertical distillation box from top to bottom, and a heating element arranged in the bottom plate of the distillation chamber; the condensation unit comprises a condensation column arranged in the center of the vertical distillation box, and a concentric condensation column arranged in the condensation column; each of the distillation chambers is provided with a concentric insulation cylinder surrounding the condensation column; an annular insulation space is formed between the concentric insulation cylinder, the condensation column and the top and bottom surfaces of the distillation chamber; a group of upper vents are provided on the upper part of the concentric insulation cylinder; the condensation column corresponds to each annular insulation space; A group of lower air vents are respectively provided at the lower position of the chamber, the upper end of the concentric condensation riser passes through the top surface of the vertical distillation box, the lower end of the condensation riser passes through the bottom surface of the vertical distillation box and is fixed with a head, a liquid receiving hopper is fixed at the junction of the two adjacent distillation chambers corresponding to the upper and lower distillation chambers in the condensation riser, the lower end of the liquid receiving hopper is connected to an inclined discharge pipe, the lower end of the inclined discharge pipe passes through the condensation riser and the concentric insulation cylinder and is led to the distillation chamber at the lower position, a one-way valve is provided at the lower end of the inclined discharge pipe, the lower end of the concentric condensation riser passes through the bottom surface of each liquid receiving hopper and the bottom surface of the head in turn, a liquid collection outlet is fixed on the side of the head, and a liquid inlet is provided on the upper part of the side wall of the distillation chamber at the highest position.

[0007] In the above-mentioned separation device for recovering high-purity n-hexane, the vertical distillation box is provided with a collecting chamber below the lowest distillation chamber, the bottom of the collecting chamber is provided with a liquid discharge port, and the bottom surface of each annular insulation space is provided with a liquid drain valve, the upper and lower adjacent annular insulation spaces are connected by a liquid drain valve, and the lowest annular insulation space and the collecting chamber are connected by a liquid drain valve.

[0008] In the above-mentioned separation device for recovering high-purity n-hexane, a liquid discharge port is provided at the lower part of the side wall of each distillation chamber.

[0009] In the above-mentioned separation device for recovering high-purity n-hexane, the upper edge of the liquid receiving bucket is in close contact with and fixed to the inner wall of the condensation column, and the concentric condensation column is fixed with multiple umbrella-shaped fins at the upper and lower positions of the liquid receiving bucket, and the umbrella-shaped fins close to the upper edge of the liquid receiving bucket have the largest diameter.

[0010] In the above-mentioned separation device for recovering high-purity n-hexane, a cooling liquid circulation system is connected between the upper and lower ends of the concentric condensation riser.

[0011] The beneficial effects of the utility model are:

[0012] The feed is distilled and separated from each distillation chamber of the vertical distillation box from top to bottom. Specifically, after being heated and evaporated in the distillation chamber, the crude n-hexane vapor passes through the upper vent hole on the upper part of the corresponding concentric insulation cylinder and the lower vent hole of the condensation column in turn, enters the condensation column, and is cooled by the pre-cooled concentric condensation column to condense into liquid, drips into the liquid receiving bucket, and then is placed in the adjacent distillation chamber below the liquid receiving bucket to perform the distillation operation of the above process again. The waste liquid is retained in the distillation chamber and discharged in time. Finally, the high-purity n-hexane vapor after distillation in all distillation chambers is condensed into liquid in the head at the bottom of the condensation column and can be discharged through the liquid collection outlet. In the whole process, the condensation path is extended to avoid the steam short-circuiting to the last distillation chamber before condensation, and fully participates in the repeated distillation and separation of multiple distillation chambers, which significantly enhances the separation effect, thereby significantly improving the product purity of n-hexane. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the utility model;

[0014] Figure 2 yes Figure 1 Enlarged view of part A in the middle.

[0015] In the figure: 1. vertical distillation box, 2. heating element, 3. concentric insulation cylinder, 4. one-way valve, 5. inclined discharge pipe, 6. condensation cylinder, 7. cooling liquid circulation system, 8. collecting chamber, 9. liquid discharge port, 10. head, 11. concentric condensation vertical pipe, 12. liquid collection outlet, 13. umbrella-shaped fins, 14. liquid discharge port, 15. upper vent, 16. lower vent, 17. liquid receiving bucket, 18. liquid drain valve, 19. liquid inlet, 20. annular insulation space, 21. distillation chamber. DETAILED DESCRIPTION

[0016] The utility model is described in detail according to the accompanying drawings of the specification.

[0017] like Figure 1 , Figure 2 As shown, the separation device for recovering high-purity n-hexane includes a distillation unit and a condensation unit.

[0018] The distillation unit comprises a vertical distillation box 1, five distillation chambers 21 arranged in the vertical distillation box 1 from top to bottom, and a heating element 2 arranged in the bottom plate of the distillation chamber 21. The condensation unit comprises a condensation column 6 arranged in the center of the vertical distillation box 1, and a concentric condensation column 11 arranged in the condensation column 6.

[0019] Each of the distillation chambers 21 is provided with a concentric insulation tube 3 surrounding the condensation column 6, and an annular insulation space 20 is formed between the concentric insulation tube 3, the condensation column 6 and the top and bottom surfaces of the distillation chamber 21. A group of upper vents 15 are provided on the upper part of the concentric insulation tube 3, and a group of lower vents 16 are provided on the condensation column 6 corresponding to the lower part of each annular insulation space 20. The upper end of the concentric condensation column 11 passes through the top surface of the vertical distillation box 1, and the lower end of the condensation column 6 passes through the bottom surface of the vertical distillation box 1 and is fixed with a head 10. A liquid receiving hopper 17 is fixed at the intersection of the two adjacent distillation chambers 21 at the upper and lower sides of the condensation column 6, and the lower end of the liquid receiving hopper 17 is connected to the oblique material pipe 5, and the lower end of the oblique material pipe 5 passes through the condensation column 6 and the concentric insulation tube 3 and is led to the distillation chamber 21 at the lower position, and a one-way valve 4 is provided at the lower end of the oblique material pipe 5. The lower end of the concentric condensation riser 11 passes through the bottom surface of each liquid receiving bucket 17 and the bottom surface of the head 10 in sequence, and the upper and lower ends of the concentric condensation riser 11 are connected to the cooling liquid circulation system 7. A liquid collection outlet 12 is fixed on the side of the head 10, and a liquid inlet 19 is provided on the upper part of the side wall of the highest distillation chamber 21.

[0020] In this embodiment, the vertical distillation box 1 is provided with a collecting chamber 8 below the lowest distillation chamber 21, and a liquid discharge port 9 is provided at the bottom of the collecting chamber 8. A liquid drain valve 18 is provided on the bottom surface of each annular heat-insulating space 20, and the upper and lower adjacent annular heat-insulating spaces 20 are connected by the liquid drain valve 18, and the lowest annular heat-insulating space 20 and the collecting chamber 8 are connected by the liquid drain valve 18. The collecting chamber 8 is used to collect low-purity defective liquid in each annular heat-insulating space 20, and can be discharged in time through the liquid discharge port 9 and then re-sent to the device. A liquid discharge port 14 is provided at the lower part of the side wall of each distillation chamber 21, which is used to discharge the residual liquid accumulated in each distillation chamber 21 in time.

[0021] The upper edge of the liquid receiving hopper 17 is in close contact with and fixed to the inner wall of the condensation column 6, and the concentric condensation column 11 is fixed with multiple umbrella-shaped fins 13 at the upper and lower positions of the liquid receiving hopper 17. The umbrella-shaped fins 13 close to the upper edge of the liquid receiving hopper 17 have the largest diameter, which to a certain extent prevents the steam entering from the lower vent 16 from directly rushing to the receiving hopper 17.

[0022] Working principle:

[0023] 1. The material to be separated first enters the highest distillation chamber 21 through the liquid inlet 19. After being heated and evaporated, the crude n-hexane vapor enters the annular insulation space 20 through the upper vent 15 of the corresponding concentric insulation cylinder 3, and then enters the condensation column 6 through the lower vent 16 of the condensation column 6. It is cooled by the pre-cooled concentric condensation column 11 and the umbrella-shaped fins 13 to condense into liquid, drips into the liquid receiving bucket 17, and then is placed into the second distillation chamber 21 from the inclined discharge pipe 5 at the lower end of the liquid receiving bucket 17; the liquid falling into the second distillation chamber 21 is heated and evaporated, and the vapor passes through the upper vent 15 of the corresponding concentric insulation cylinder 3. 5 enters the corresponding annular heat-insulating space 20, and then enters the condensation column 6 through the lower vent hole 16 of the condensation column 6, and is cooled again by the pre-cooled concentric condensation column 11 and the umbrella-shaped fins 13 to condense into liquid, dripping into the second liquid receiving bucket 17, and then put into the third distillation chamber 21 from the inclined discharge pipe 5 at the lower end of the liquid receiving bucket 17; and so on, each distillation chamber 21 repeats the distillation operation, and the steam of the fifth distillation chamber 21 finally enters the condensation column 6 at the bottom of the lowest liquid receiving bucket 17, and is collected by the head 10 after condensation, and can be discharged from the liquid collecting outlet 12, so as to achieve the purpose of repeated distillation and purification.

[0024] 2. The condensate generated when the steam passes through each annular insulation space 20 can be discharged downward by the drain valve 18, and finally falls into the collecting chamber 8. After being discharged in time through the drain port 9, it can be re-sent into the device.

[0025] 3. The waste liquid is retained in each distillation chamber 21 and can be discharged in a timely manner through each drain port 14.

[0026] 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 separation device for recovering high-purity n-hexane, comprising a distillation unit and a condensation unit, characterized in that: The distillation unit comprises a vertical distillation box, a plurality of distillation chambers arranged in the vertical distillation box from top to bottom, and a heating element arranged in the bottom plate of the distillation chamber. The condensation unit comprises a condensation column arranged in the center of the vertical distillation box, and a concentric condensation column arranged in the condensation column. Each of the distillation chambers is provided with a concentric insulation cylinder surrounding the condensation column. An annular insulation space is formed between the concentric insulation cylinder, the condensation column and the top and bottom surfaces of the distillation chamber. A group of upper vents are arranged on the upper part of the concentric insulation cylinder. A group of lower vents are respectively arranged on the condensation column corresponding to the lower part of each annular insulation space. The upper end of the concentric condensation riser passes through the top surface of the vertical distillation box, the lower end of the condensation riser passes through the bottom surface of the vertical distillation box and is fixed with a head, a liquid receiving hopper is fixed at the junction of the two adjacent distillation chambers on the upper and lower sides of the condensation riser, the lower end of the liquid receiving hopper is connected to an inclined discharge pipe, the lower end of the inclined discharge pipe passes through the condensation riser and the concentric insulation tube and is led to the distillation chamber at the lower position, a one-way valve is provided at the lower end of the inclined discharge pipe, the lower end of the concentric condensation riser passes through the bottom surface of each liquid receiving hopper and the bottom surface of the head in turn, a liquid collection outlet is fixed on the side of the head, and a liquid inlet is provided on the upper part of the side wall of the distillation chamber at the highest position.

2. The separation device for recovering high-purity normal hexane according to claim 1, characterized in that: The vertical distillation box is provided with a collecting chamber below the lowest distillation chamber, a liquid discharge port is provided at the bottom of the collecting chamber, and a liquid drain valve is provided on the bottom surface of each annular insulation space. The upper and lower adjacent annular insulation spaces are connected by the liquid drain valve, and the lowest annular insulation space and the collecting chamber are connected by the liquid drain valve.

3. The separation device for recovering high-purity normal hexane according to claim 1, characterized in that: A liquid discharge port is respectively arranged at the lower part of the side wall of each distillation chamber.

4. The separation device for recovering high-purity normal hexane according to claim 1, characterized in that: The upper edge of the liquid receiving bucket is in close contact with and fixed to the inner wall of the condensation vertical tube. The concentric condensation vertical tube is fixed with multiple umbrella-shaped fins at the upper and lower positions of the liquid receiving bucket. The umbrella-shaped fins close to the upper edge of the liquid receiving bucket have the largest diameter.

5. The separation device for recovering high-purity n-hexane according to claim 1, characterized in that: A cooling liquid circulation system is connected between the upper and lower ends of the concentric condensation riser.

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