A device for refining cyclohexanone by dehydrogenation of cyclohexanol

Abstract

The present invention provides a device for refining cyclohexanone by dehydrogenation of cyclohexanol, comprising an alcohol first tower, a dehydrogenation reactor, a dehydrogenation heat exchanger, an alcohol tower feed heat exchanger, a light first tower, a coupled reboiler, a light second tower, a ketone tower, and an alcohol second tower. The device of the present invention redesigns the six-tower process to achieve the refining and separation of cyclohexanol dehydrogenation materials, and couples and utilizes the available heat source and cold source. Using the device of the present invention to purify cyclohexanone can improve the product yield while saving steam consumption, reducing the operating cost of the device, and reducing the discharge of three wastes.

Description

Technical Field

[0001] The invention belongs to the field of organic chemical synthesis, and in particular relates to a device for refining cyclohexanone by dehydrogenating cyclohexanol. Background Art

[0002] Cyclohexanone is an important chemical raw material, mainly used in the preparation of nylon intermediates such as caprolactam and adipic acid, and is widely used in synthetic rubber, organic solvents and industrial coatings.

[0003] The traditional cyclohexene-based cyclohexanone process mainly includes main processes such as benzene hydrogenation, cyclohexene refining, cyclohexene hydration, cyclohexanol refining, cyclohexanol dehydrogenation, and cyclohexanone refining, and the refining unit is the main energy-consuming process in the entire process.

[0004] The invention patent with publication number CN106083544B discloses a cyclohexanone refining and cyclohexanol recycling method and system, the main steps of which are as follows: sending the alcohol-ketone mixture into a light component removal tower to remove light components, sending the material taken out from the bottom of the tower into a cyclohexanone product tower, taking out a high-purity cyclohexanone product from the top of the tower, taking out a crude product mainly containing cyclohexanol from the bottom of the tower, and then sending it to a cyclohexanol recovery tower, taking out cyclohexanol from the top of the tower; the taken out cyclohexanol is mixed with an appropriate amount of water, heated and sent to a cyclohexanol dehydrogenation reaction The dehydrogenation reaction is carried out in a device to obtain a mixed product containing cyclohexanol, cyclohexanone and water. The dehydrogenation product is separated into gas and liquid after two-stage cooling. The gas phase and liquid phase are sent to a dehydration tower for dehydration treatment. The oily wastewater removed from the top of the tower is sent to a cyclohexane extraction tower, and the upper oil phase obtained is sent to an alcohol ketone recovery tower. The oil phase containing cyclohexanone and cyclohexanol obtained at the bottom of the alcohol ketone recovery tower is returned to the dehydration tower for recycling. The advantages are that the product cyclohexanone has high purity, cyclohexanol is efficiently and high-yield converted into cyclohexanone, and the system has high energy integration and low energy consumption.

[0005] However, the technical solution in the above invention patent requires condensing cyclohexanol before vaporizing it, which increases energy consumption. Liquid feed is mostly used as feed, which requires more energy to vaporize the feed. The intermediate products of each reaction are independent of each other, and the heat in the intermediate products cannot be fully utilized, resulting in energy waste. Part of the cyclohexanone in the alcohol-ketone mixture cannot be recovered after entering the cyclohexanol recovery tower, resulting in product waste and increased production costs. Summary of the invention

[0006] In view of this, the present invention aims to propose a device for dehydrogenating cyclohexanol to purify cyclohexanone, so as to achieve comprehensive utilization of heat, reduce energy consumption, make full use of raw materials, avoid waste, reduce production costs and improve economic benefits.

[0007] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0008] A device for refining cyclohexanone by dehydrogenation of cyclohexanol comprises an alcohol tower and a dehydrogenation reactor. The raw material cyclohexanol is injected into the alcohol tower through a feed port at the upper end of the alcohol tower, and cyclohexanol is refluxed and separated in the alcohol tower. Cyclohexanol vapor can be discharged from a discharge port at the top of the alcohol tower. The cyclohexanol vapor as a raw material for dehydrogenation reaction can directly enter the dehydrogenation reactor for dehydrogenation reaction without condensation and re-evaporation, thereby reducing energy consumption.

[0009] A dehydrogenation heat exchanger, wherein the tube-side feed port of the dehydrogenation heat exchanger is connected to the top discharge port of the alcohol tower, the tube-side discharge port of the dehydrogenation heat exchanger is connected to the feed port of the dehydrogenation reactor, and the shell-side feed port of the dehydrogenation heat exchanger is connected to the discharge port of the dehydrogenation reactor. The gas discharged from the top discharge port of the alcohol tower undergoes heat exchange with the dehydrogenation product discharged from the dehydrogenation reactor in the dehydrogenation heat exchanger to preheat the gas so that the heat is fully utilized. The cyclohexanol after heat exchange enters the dehydrogenation reactor to undergo dehydrogenation reaction to generate crude alcohol ketone containing cyclohexanone;

[0010] An alcohol tower feed heat exchanger, wherein the shell side feed port of the alcohol tower feed heat exchanger is connected to the shell side discharge port of the dehydrogenation heat exchanger, and the crude alcohol ketone undergoes secondary heat exchange at the alcohol tower feed heat exchanger after heat exchange, thereby realizing secondary utilization of heat, and the tube side discharge port of the alcohol tower feed heat exchanger is connected to the middle feed port of the first alcohol tower, and separation is performed in the first alcohol tower to realize material circulation;

[0011] A light tower, wherein the middle feed port of the light tower is connected to the shell-side liquid phase discharge port of the alcohol tower feed heat exchanger, and the light components in the crude alcohol ketone are evaporated from the top discharge port of the light tower;

[0012] A coupled reboiler, wherein the shell side feed port of the coupled reboiler is connected to the discharge port at the top of the light tower, and the shell side discharge port of the coupled reboiler is connected to the reflux port at the top of the light tower. A part of the light components discharged from the top of the light tower is transported to the coupled reboiler for heat exchange. As a heat source of the coupled reboiler, it can provide heat for the bottom of the cyclohexanone refining process. After the heat exchange, the light components can be returned to the light tower for circulation;

[0013] Light tower 2, wherein the middle feed port of the light tower 2 is connected with the top discharge port of the light tower 1, the bottom discharge port of the light tower 2 is connected with the middle feed port of the light tower 1, another part of the light components discharged from the top of the light tower 1 is transported to the light tower 2, the material entering the light tower 2 is the uncondensed gaseous material discharged from the top of the light tower 1, the light tower 2 is used to recover cyclohexanone in the material discharged from the top of the light tower 1, and the gaseous phase feeding method further improves the heat utilization rate and reduces energy consumption;

[0014] A ketone tower, wherein a middle feed port of the ketone tower is respectively connected with a bottom discharge port of a light tower and a tube-side discharge port of a coupled reboiler, materials discharged from the bottom discharge port of the light tower enter the ketone tower as a raw material, and cyclohexanone is discharged from a top discharge port of the ketone tower, and the bottom discharge port of the ketone tower is respectively connected with a tube-side feed port of the coupled reboiler and a tube-side feed port of an alcohol tower feed heat exchanger, and materials discharged from the bottom discharge port of the ketone tower are mainly composed of cyclohexanol and heavy components, a part of which returns to the ketone tower for separation after heat exchange at the coupled reboiler, and the other part enters the alcohol tower as a raw material for separation after heat exchange at the alcohol tower feed heat exchanger, thereby realizing material circulation;

[0015] The second alcohol tower has a top feed port connected to the bottom discharge port of the first alcohol tower, and the top discharge port of the second alcohol tower is connected to the bottom feed port of the ketone tower. The second alcohol tower is used to separate cyclohexanol and heavy components, wherein the heavy component X oil is discharged from the bottom discharge port of the second alcohol tower, and the separated cyclohexanol enters the ketone tower for recycling as a raw material.

[0016] Furthermore, a dehydration tower is provided between the light tower and the alcohol tower feed heat exchanger, the feed port of the dehydration tower is connected with the shell side liquid phase discharge port of the alcohol tower feed heat exchanger, the bottom discharge port of the dehydration tower is connected with the middle feed port of the light tower, and the crude alcohol ketone after heat exchange at the alcohol tower feed heat exchanger is dehydrated in the dehydration tower and then enters the light tower.

[0017] Furthermore, a dehydrogenation pump tank is provided between the dehydration tower and the alcohol tower feed heat exchanger, the feed port of the dehydrogenation pump tank is connected to the shell side liquid phase discharge port of the alcohol tower feed heat exchanger, and the discharge port of the dehydrogenation pump tank is connected to the feed port of the dehydration tower.

[0018] Furthermore, it also includes a dehydrogenation condenser, the feed port of the dehydrogenation condenser is connected with the shell side gas phase discharge port of the alcohol tower feed heat exchanger, and the liquid phase discharge port of the dehydrogenation condenser is connected with the feed port of the dehydrogenation pump tank. After the gas mixture sent out from the dehydrogenation reactor is heat exchanged by the dehydrogenation heat exchanger, and then heat exchanged with the ketone tower kettle material at the alcohol tower feed heat exchanger, the formed liquid phase flows into the dehydrogenation pump tank by gravity, and the uncondensed gas phase enters the dehydrogenation condenser for further condensation, and the recovered alcohol ketone enters the dehydrogenation pump tank.

[0019] Furthermore, it also includes a light-first condenser and a light-first reflux tank, the feed port of the light-first condenser is connected with the discharge port at the top of the light-first tower, the liquid phase discharge port of the light-first condenser is connected with the feed port of the light-first reflux tank, the feed port of the light-first reflux tank is also connected with the shell-side discharge port of the coupled reboiler, the discharge port of the light-first reflux tank is connected with the reflux port at the top of the light-first tower, a part of the light components discharged from the top of the light-first tower is transported to the coupled reboiler for heat exchange as a heat source for the coupled reboiler, another part is transported to the light-second tower, and the remaining part flows into the light-first reflux tank after condensation at the light-first condenser, and finally flows back to the light-first tower for circulation.

[0020] Furthermore, it also includes a light second condenser and a light second reflux tank, the feed port of the light second condenser is connected with the discharge port at the top of the light second tower, the liquid phase discharge port of the light second condenser is connected with the feed port of the light second reflux tank, the discharge port of the light second reflux tank is connected with the reflux port at the top of the light second tower, the light component is evaporated from the top of the light second tower, and the condensate after condensation at the light second condenser enters the light second reflux tank and flows back to the light second tower for circulation, the non-condensable gas is extracted by the vacuum system, and the light oil in the light second reflux tank can also be sent out of the boundary area for recovery through a reflux pump.

[0021] Furthermore, it also includes a ketone condenser and a ketone reflux tank, wherein the feed port of the ketone condenser is connected to the discharge port at the top of the ketone tower, the liquid phase discharge port of the ketone condenser is connected to the feed port of the ketone reflux tank, the discharge port of the ketone reflux tank is connected to the reflux port at the top of the ketone tower, cyclohexanone is evaporated from the top of the ketone tower, and the condensate flows into the ketone reflux tank after condensation by the ketone condenser, and the non-condensable gas is extracted by the vacuum system. The condensate is partially sent to the top of the ketone tower as reflux through the ketone tower reflux pump, and the rest is used as a cyclohexanone product delivery device.

[0022] Furthermore, it also includes an alcohol condenser, wherein the feed port of the alcohol condenser is connected to the discharge port at the top of the alcohol tower, and the discharge port of the alcohol condenser is connected to the reflux port at the top of the alcohol tower. Cyclohexanol is extracted from the top of the alcohol tower, part of which enters the dehydrogenation reactor as a reaction raw material, and the other part is condensed at the alcohol condenser to form a condensate, and the condensate flows back to the alcohol tower for circulation.

[0023] Furthermore, it also includes an alcohol reboiler and an alcohol reboiler. The feed port of the alcohol reboiler is connected to the bottom circulation port of the alcohol tower, the discharge port of the alcohol reboiler is connected to the bottom feed port of the alcohol tower, the feed port of the alcohol reboiler is connected to the bottom circulation port of the alcohol tower, the discharge port of the alcohol reboiler is connected to the bottom feed port of the alcohol tower, the alcohol reboiler is connected to the bottom circulation port of the alcohol tower, and the discharge port of the alcohol reboiler is connected to the bottom feed port of the alcohol tower. The alcohol reboiler and the alcohol reboiler provide external heat source support for the alcohol tower and the alcohol tower, respectively.

[0024] Furthermore, the alcohol tower 1 is operated at positive pressure with an operating pressure of 30-100 kPa. The gas pressure at the top of the alcohol tower 1 is greater than the pressure of the dehydrogenation reactor. The gas discharged from the alcohol tower 1 can directly enter the dehydrogenation reactor without condensation and re-vaporization. The alcohol tower 2 is a distillation tower operated at negative pressure.

[0025] Compared with the prior art, the device for refining cyclohexanone by dehydrogenation of cyclohexanol described in the present invention has the following advantages:

[0026] (1) The cyclohexanol in the device of the present invention directly enters the dehydrogenation reactor through the top of the alcohol tower without condensation and re-vaporization, thus saving steam consumption;

[0027] (2) Thermal coupling is performed between the light tower and the ketone tower in the device of the present invention, which can save steam and circulating water consumption;

[0028] (3) The light tower 2 in the device described in the present invention adopts gas phase feed, saving steam and circulating water consumption;

[0029] (4) The alcohol second tower in the device described in the present invention adopts a stripping tower, and the gas phase at the top of the tower enters the ketone tower, thereby reducing the loss of cyclohexanone product;

[0030] (5) The alcohol tower 2 and the ketone tower in the device of the present invention can share a vacuum system, saving project investment;

[0031] (6) The device described in the present invention uses cyclohexanol dehydrogenation material as alcohol tower feed heating, recovers heat in the material, and reduces steam consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0033] Figure 1 The figure is a schematic diagram of the connection structure of the device described in the embodiment of the present invention.

[0034] Description of reference numerals:

[0035] 1. Alcohol tower 1; 2. Dehydrogenation reactor; 3. Alcohol tower feed heat exchanger; 4. Light tower 1; 5. Coupled reboiler; 6. Light tower 2; 7. Ketone tower; 8. Alcohol tower 2; 9. Dehydration tower; 10. Dehydrogenation pump tank; 11. Dehydrogenation condenser; 12. Light 1 condenser; 13. Light 1 reflux tank; 14. Light 2 condenser; 15. Light 2 reflux tank; 16. Ketone condenser; 17. Ketone reflux tank; 18. Alcohol 1 condenser; 19. Alcohol 1 reboiler; 20. Alcohol 2 reboiler; 21. Dehydrogenation heat exchanger. DETAILED DESCRIPTION

[0036] Unless otherwise defined, the technical terms used in the following examples have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods, unless otherwise specified, are all conventional methods.

[0037] The present invention will be described in detail below with reference to the embodiments and the accompanying drawings.

[0038] In order to reduce the energy consumption of the device and reduce the consumption of steam and circulating water, the present invention, through full process simulation and heat exchange network analysis, proposes a six-tower process for the refining and separation of cyclohexanol dehydrogenation materials, and couples the possible heat sources and cold sources for utilization. The new process can not only save steam consumption, but also reduce the emission of three wastes.

[0039] The device for refining cyclohexanone by dehydrogenation of cyclohexanol in the present invention comprises an alcohol tower 1, a dehydrogenation reactor 2, a dehydrogenation heat exchanger 21, an alcohol tower feed heat exchanger 3, a light tower 1, a coupling reboiler 5, a light tower 2 6, a ketone tower 7, and an alcohol tower 2 8. The raw material cyclohexanol is injected into the alcohol tower 1 through a feed port at the upper end of the alcohol tower 1, and cyclohexanol is refluxed and separated in the alcohol tower 1. Cyclohexanol vapor can be discharged from a discharge port at the top of the alcohol tower 1. The cyclohexanol vapor as a raw material for dehydrogenation reaction can directly enter the dehydrogenation reactor 2 for dehydrogenation reaction without condensation and re-vaporization, thereby reducing energy consumption.

[0040] The tube-side feed port of the dehydrogenation heat exchanger 21 is connected to the top discharge port of the alcohol tower 1, the tube-side discharge port of the dehydrogenation heat exchanger 21 is connected to the feed port of the dehydrogenation reactor 2, and the shell-side feed port of the dehydrogenation heat exchanger 21 is connected to the discharge port of the dehydrogenation reactor 2. The gas discharged from the top discharge port of the alcohol tower 1 undergoes heat exchange with the dehydrogenation product discharged from the dehydrogenation reactor 2 in the dehydrogenation heat exchanger 21, and the gas is preheated to fully utilize the heat. After the heat exchange, the cyclohexanol enters the dehydrogenation reactor 2, undergoes a dehydrogenation reaction, and generates a crude alcohol ketone containing cyclohexanone;

[0041] The shell side feed port of the alcohol tower feed heat exchanger 3 is connected with the shell side discharge port of the dehydrogenation heat exchanger 21, and the crude alcohol ketone undergoes secondary heat exchange at the alcohol tower feed heat exchanger 3 after heat exchange, so as to realize secondary utilization of heat, and the tube side discharge port of the alcohol tower feed heat exchanger 3 is connected with the middle feed port of the alcohol first tower 1, and the material of the tube side of the alcohol tower feed heat exchanger 3 enters the alcohol first tower 1 as a raw material for re-separation after heat exchange, so as to realize material circulation;

[0042] The middle feed port of the light tower 4 is connected to the shell side liquid phase discharge port of the alcohol tower feed heat exchanger 3, and the crude alcohol ketone after the secondary heat exchange enters the light tower 4, and the light components in the crude alcohol ketone are evaporated from the top discharge port of the light tower 4;

[0043] The shell-side feed port of the coupled reboiler 5 is connected to the discharge port at the top of the light tower 4, and the shell-side discharge port of the coupled reboiler 5 is connected to the reflux port at the top of the light tower 4. A part of the light components discharged from the top of the light tower 4 is transported to the coupled reboiler 5 for heat exchange. As a heat source of the coupled reboiler 5, it can provide heat to the bottom of the tower for the cyclohexanone refining process. After the heat exchange, the light components can be returned to the light tower 4 for circulation.

[0044] The middle feed port of the light tower 2 6 is connected with the top discharge port of the light tower 1 4, and the bottom discharge port of the light tower 2 6 is connected with the middle feed port of the light tower 1 4. Another part of the light components discharged from the top of the light tower 1 4 is transported to the light tower 2 6. The material entering the light tower 2 6 is the uncondensed gaseous material discharged from the top of the light tower 1 4. The light tower 2 6 is used to recover cyclohexanone in the material discharged from the top of the light tower 1 4. The gaseous phase feeding method further improves the heat utilization rate and reduces energy consumption.

[0045] The middle feed port of the ketone tower 7 is respectively connected with the bottom discharge port of the light tower 1 4 and the tube-side discharge port of the coupled reboiler 5. The material discharged from the bottom discharge port of the light tower 1 4 enters the ketone tower 7 as a raw material, and the cyclohexanone in the material separated by the ketone tower 7 is discharged from the top discharge port of the ketone tower 7. The bottom discharge port of the ketone tower 7 is respectively connected with the tube-side feed port of the coupled reboiler 5 and the tube-side feed port of the alcohol tower feed heat exchanger 3. The material discharged from the bottom discharge port of the ketone tower 7 is mainly composed of cyclohexanol and heavy components. After heat exchange at the coupled reboiler 5, a part of it returns to the ketone tower 7 for separation, and the other part enters the alcohol tower 1 as a raw material for re-separation after heat exchange at the alcohol tower feed heat exchanger 3, thereby realizing material circulation;

[0046] The top feed port of the alcohol tower 2 8 is communicated with the bottom discharge port of the alcohol tower 1, and the top discharge port of the alcohol tower 2 8 is communicated with the bottom feed port of the ketone tower 7. The alcohol tower 2 8 is used to separate cyclohexanol and heavy components, wherein the heavy component X oil is discharged from the bottom discharge port of the alcohol tower 2 8, and the separated cyclohexanol enters the ketone tower 7 for recycling as a raw material.

[0047] Furthermore, a dehydration tower 9 is provided between the light tower 4 and the alcohol tower feed heat exchanger 3, the feed port of the dehydration tower 9 is connected with the shell side liquid phase discharge port of the alcohol tower feed heat exchanger 3, the bottom discharge port of the dehydration tower 9 is connected with the middle feed port of the light tower 4, and the crude ketone after heat exchange at the alcohol tower feed heat exchanger 3 is dehydrated in the dehydration tower 9 and then enters the light tower 4.

[0048] Furthermore, a dehydrogenation pump tank 10 is provided between the dehydration tower 9 and the alcohol tower feed heat exchanger 3 , the feed port of the dehydrogenation pump tank 10 is connected to the shell side liquid phase discharge port of the alcohol tower feed heat exchanger 3 , and the discharge port of the dehydrogenation pump tank 10 is connected to the feed port of the dehydration tower 9 .

[0049] Furthermore, it also includes a dehydrogenation condenser 11, the feed port of the dehydrogenation condenser 11 is connected to the shell side gas phase discharge port of the alcohol tower feed heat exchanger 3, and the liquid phase discharge port of the dehydrogenation condenser 11 is connected to the feed port of the dehydrogenation pump tank 10. The gas mixture sent out from the dehydrogenation reactor 2 is heat exchanged through the dehydrogenation heat exchanger 21, and then heat exchanged through the bottom material of the ketone tower 7 at the alcohol tower feed heat exchanger 3. The formed liquid phase flows into the dehydrogenation pump tank 10 by gravity, and the uncondensed gas phase enters the dehydrogenation condenser 11 for further condensation and recovery of alcohol and ketone, which enters the dehydrogenation pump tank 10.

[0050] Furthermore, it also includes a light-first condenser 12 and a light-first reflux tank 13, the feed port of the light-first condenser 12 is connected with the discharge port at the top of the light-first tower 4, the liquid phase discharge port of the light-first condenser 12 is connected with the feed port of the light-first reflux tank 13, the feed port of the light-first reflux tank 13 is also connected with the shell-side discharge port of the coupled reboiler 5, the discharge port of the light-first reflux tank 13 is connected with the reflux port at the top of the light-first tower 4, a part of the light components discharged from the top of the light-first tower 4 is transported to the coupled reboiler 5 for heat exchange as a heat source for the coupled reboiler 5, another part is transported to the light-second tower 6, and the remaining part flows into the light-first reflux tank 13 after condensation at the light-first condenser 12, and finally flows back to the light-first tower 4 for circulation.

[0051] Furthermore, it also includes a light second condenser 14 and a light second reflux tank 15, the feed port of the light second condenser 14 is connected with the discharge port at the top of the light second tower 6, the liquid phase discharge port of the light second condenser 14 is connected with the feed port of the light second reflux tank 15, the discharge port of the light second reflux tank 15 is connected with the reflux port at the top of the light second tower 6, the light component is evaporated from the top of the light second tower 6, and the condensate after condensation at the light second condenser 14 enters the light second reflux tank 15, and flows back to the light second tower 6 for circulation, the non-condensable gas is extracted by the vacuum system, and the light oil in the light second reflux tank 15 can also be sent out of the boundary area for recovery through a reflux pump.

[0052] Furthermore, it also includes a ketone condenser 16 and a ketone reflux tank 17, the feed port of the ketone condenser 16 is connected to the top discharge port of the ketone tower 7, the liquid phase discharge port of the ketone condenser 16 is connected to the feed port of the ketone reflux tank 17, the discharge port of the ketone reflux tank 17 is connected to the top reflux port of the ketone tower 7, cyclohexanone is evaporated from the top of the ketone tower 7, and the condensate flows into the ketone reflux tank 17 after condensation by the ketone condenser 16, and the non-condensable gas is extracted by the vacuum system. The condensate is partially sent to the top of the ketone tower 7 as reflux through the ketone tower 7 reflux pump, and the rest is used as a cyclohexanone product delivery device.

[0053] Furthermore, it also includes an alcohol condenser 18, the feed port of the alcohol condenser 18 is connected to the discharge port at the top of the alcohol tower 1, and the discharge port of the alcohol condenser 18 is connected to the reflux port at the top of the alcohol tower 1. Cyclohexanol is extracted from the top of the alcohol tower 1, part of which enters the dehydrogenation reactor 2 as a reaction raw material, and the other part is condensed at the alcohol condenser 18 to form a condensate, which flows back to the alcohol tower 1 for circulation.

[0054] Furthermore, it also includes an alcohol reboiler 19 and an alcohol reboiler 20, the feed port of the alcohol reboiler 19 is connected to the bottom circulation port of the alcohol tower 1, the discharge port of the alcohol reboiler 19 is connected to the bottom feed port of the alcohol tower 1, the feed port of the alcohol reboiler 20 is connected to the bottom circulation port of the alcohol tower 2 8, the discharge port of the alcohol reboiler 20 is connected to the bottom feed port of the alcohol tower 2 8, the alcohol reboiler 19 and the alcohol reboiler 20 provide external heat source support for the alcohol tower 1 and the alcohol tower 2 8 respectively.

[0055] Furthermore, the alcohol tower 1 is operated at positive pressure with an operating pressure of 30-100 kPa. The gas pressure at the top of the alcohol tower 1 is greater than the pressure of the dehydrogenation reactor 2. The gas discharged from the alcohol tower 1 can directly enter the dehydrogenation reactor 2 without condensation and re-vaporization. The alcohol tower 2 8 is a distillation tower operated at negative pressure.

[0056] The process flow of the device of the present invention for dehydrogenation and refining of cyclohexanone is as follows:

[0057] The cyclohexanol feed is used as the top reflux of the alcohol tower 1, and the gaseous cyclohexanol at the top of the alcohol tower 1 directly enters the dehydrogenation reactor 2 after heat exchange with the dehydrogenation product;

[0058] The gas mixture sent out from the dehydrogenation reactor 2 is heat exchanged in the dehydrogenation heat exchanger 21, and then heat exchanged through the ketone tower 7 bottom material. The gas phase is condensed and enters the dehydrogenation pump tank 10, and the liquid phase flows by gravity into the dehydrogenation pump tank 10. The hydrogen is compressed and purified and then sent out of the boundary area. The crude alcohol ketone is dehydrated and sent to the light tower 4;

[0059] The light components in the crude ketone are evaporated from the top of the light first tower 4, a part of which is heated by the coupling reboiler 5 for thermal coupling, and a stream of the uncondensed part in the coupling reboiler 5 is extracted and enters the light second tower 6. After the uncondensed gas phase is condensed at the top of the tower, the condensate flows into the reflux tank of the light first tower 4. The condensed material in the coupling reboiler 5 flows by gravity into the light first reflux tank 13. A part of the liquid in the light first reflux tank 13 is used as reflux, and the rest is pumped to the ketone tower 7 through the discharge pump;

[0060] The light component is evaporated from the top of the light second tower 6, and the condensate enters the light second reflux tank 15 after condensation. The non-condensable gas is extracted by the vacuum system, and the light oil in the light second reflux tank 15 is sent out of the boundary area by the reflux pump;

[0061] Cyclohexanone is evaporated from the top of ketone tower 7, and the condensate flows into ketone reflux tank 17 after condensation, and non-condensable gas is extracted through vacuum system. Part of the condensate is sent to the top of ketone tower 7 as reflux, and the rest is used as cyclohexanone product delivery device. Cyclohexanol and heavy components are pumped from ketone tower 7 discharge pump to alcohol tower feed heat exchanger 3, and enter alcohol tower 1 after preheating;

[0062] Cyclohexanol is extracted from the top of the alcohol tower 1, heated by the dehydrogenation heat exchanger 21, and then enters the dehydrogenation reactor 2. Cyclohexanol and X oil are quantitatively extracted from the bottom of the alcohol tower 1 to the alcohol tower 2 8. The gas phase at the top of the alcohol tower 2 8 enters the bottom of the ketone tower 7, and the X oil extracted from the bottom of the tower is sent to the device.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for refining cyclohexanone by dehydrogenation of cyclohexanol, characterized in that: It includes an alcohol tower and a dehydrogenation reactor; A dehydrogenation heat exchanger, wherein the tube-side feed port of the dehydrogenation heat exchanger is connected to the top discharge port of the alcohol tower, the tube-side discharge port of the dehydrogenation heat exchanger is connected to the feed port of the dehydrogenation reactor, and the shell-side feed port of the dehydrogenation heat exchanger is connected to the discharge port of the dehydrogenation reactor; An alcohol tower feed heat exchanger, wherein the shell side feed port of the alcohol tower feed heat exchanger is connected to the shell side discharge port of the dehydrogenation heat exchanger, and the tube side discharge port of the alcohol tower feed heat exchanger is connected to the middle feed port of the alcohol tower; A light tower, wherein the middle feed port of the light tower is connected to the shell-side liquid phase discharge port of the alcohol tower feed heat exchanger; A coupled reboiler, wherein the shell side feed port of the coupled reboiler is connected to the discharge port at the top of the light tower, and the shell side discharge port of the coupled reboiler is connected to the reflux port at the top of the light tower; Light tower 2, wherein the middle feed port of the light tower 2 is connected to the top discharge port of the light tower 1, and the bottom discharge port of the light tower 2 is connected to the middle feed port of the light tower 1; A ketone tower, wherein the middle feed port of the ketone tower is respectively connected to the bottom discharge port of the light tower and the tube-side discharge port of the coupled reboiler, and the bottom discharge port of the ketone tower is respectively connected to the tube-side feed port of the coupled reboiler and the tube-side feed port of the alcohol tower feed heat exchanger; The second alcohol tower, wherein the top feed port of the second alcohol tower is connected to the bottom discharge port of the first alcohol tower, and the top discharge port of the second alcohol tower is connected to the bottom feed port of the ketone tower; A dehydration tower is provided between the light tower and the alcohol tower feed heat exchanger, the feed port of the dehydration tower is connected to the shell side liquid phase discharge port of the alcohol tower feed heat exchanger, and the bottom discharge port of the dehydration tower is connected to the middle feed port of the light tower; A dehydrogenation pump tank is provided between the dehydration tower and the alcohol tower feed heat exchanger, the feed port of the dehydrogenation pump tank is connected to the shell side liquid phase discharge port of the alcohol tower feed heat exchanger, and the discharge port of the dehydrogenation pump tank is connected to the feed port of the dehydration tower; It also includes a dehydrogenation condenser, wherein the feed port of the dehydrogenation condenser is connected to the shell-side gas phase discharge port of the alcohol tower feed heat exchanger, and the liquid phase discharge port of the dehydrogenation condenser is connected to the feed port of the dehydrogenation pump tank; It also includes a light condenser and a light reflux tank, wherein the feed port of the light condenser is connected to the discharge port at the top of the light tower, the liquid phase discharge port of the light condenser is connected to the feed port of the light reflux tank, the feed port of the light reflux tank is also connected to the shell side discharge port of the coupled reboiler, and the discharge port of the light reflux tank is connected to the reflux port at the top of the light tower.

2. The device according to claim 1, characterized in that: It also includes a light-two condenser and a light-two reflux tank, wherein the feed port of the light-two condenser is connected to the discharge port at the top of the light-two tower, the liquid phase discharge port of the light-two condenser is connected to the feed port of the light-two reflux tank, and the discharge port of the light-two reflux tank is connected to the reflux port at the top of the light-two tower.

3. The device according to claim 1, characterized in that: It also includes a ketone condenser and a ketone reflux tank, wherein the feed port of the ketone condenser is connected to the top discharge port of the ketone tower, the liquid phase discharge port of the ketone condenser is connected to the feed port of the ketone reflux tank, and the discharge port of the ketone reflux tank is connected to the top reflux port of the ketone tower.

4. The device according to claim 1, characterized in that: It also includes an alcohol condenser, wherein the feed inlet of the alcohol condenser is connected to the discharge port at the top of the alcohol tower, and the discharge port of the alcohol condenser is connected to the reflux port at the top of the alcohol tower.

5. The device according to claim 1, characterized in that: It also includes an alcohol reboiler and an alcohol reboiler. The feed port of the alcohol reboiler is connected to the bottom circulation port of the alcohol tower, the discharge port of the alcohol reboiler is connected to the bottom feed port of the alcohol tower, the feed port of the alcohol reboiler is connected to the bottom circulation port of the alcohol tower, and the discharge port of the alcohol reboiler is connected to the bottom feed port of the alcohol tower.

6. The device according to claim 1, characterized in that: The alcohol tower 1 is operated at positive pressure, with an operating pressure of 30-100 kPa. The gas pressure at the top of the alcohol tower 1 is greater than the pressure of the dehydrogenation reactor. The alcohol tower 2 is a distillation tower operated at negative pressure.

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