Continuous reaction rectification equipment for synthesizing diacetone alcohol

Abstract

The invention discloses continuous reaction rectification equipment for synthesizing diacetone alcohol. The continuous reaction rectification equipment comprises a rectification tower, an opening and closing mechanism, a condensation mechanism and a rotating mechanism, by arranging the opening and closing mechanism, on the premise that the operation pressure in the rectifying tower is not influenced, the retention time of propyl alcohol in a reaction section is prolonged by adjusting gas phase flow, so that the conversion rate is increased, the sufficient reaction of propyl alcohol raw materials is ensured, and the yield of the device is increased; the condensation mechanism is arranged, so that the discharge path of by-product water is increased, the reflux of water is further reduced, the interference of water on the reaction process is reduced, and meanwhile, the product purity of diacetone alcohol is effectively improved; through the arrangement of the rotating mechanism, coaxial inversion between the reaction section and the reboiler is realized, and liquid phase mixing is promoted through stirring to further improve the separation efficiency of diacetone alcohol and water while uniform distribution of a liquid phase during backflow of propyl alcohol is ensured, so that the retention time of diacetone alcohol in a high-temperature area is shortened to reduce the occurrence of side reactions.

Description

Technical Field

[0001] The invention relates to the technical field of continuous catalytic distillation, in particular to continuous reactive distillation equipment for synthesizing diacetone alcohol. Background Art

[0002] Diacetone alcohol is a colorless, transparent liquid organic compound, usually prepared by the aldol condensation reaction of acetone. Since water is produced as a by-product when diacetone alcohol is produced, in order to efficiently separate the products and improve the reaction efficiency, continuous reaction distillation equipment and a combination of reaction and distillation are used to achieve efficient and continuous production of diacetone alcohol while reducing energy consumption and operating costs.

[0003] After searching, the Chinese patent with publication number CN118179072A includes a catalytic distillation tower, a condenser and a built-in reboiler. The catalytic distillation tower includes two parts: a reaction section and a stripping section. The feed port of the catalytic distillation tower is located between the reaction section and the stripping section. The external condenser is arranged at the top of the catalytic distillation tower. The inlet end of the condenser is connected to the top outlet of the catalytic distillation tower. The outlet end of the condenser is connected to the side inlet of the top of the catalytic distillation tower. The built-in reboiler is arranged at the bottom of the catalytic distillation tower, and a tower kettle outlet is arranged at the bottom of the catalytic distillation tower. This scheme not only significantly improves the reaction conversion rate (>99.9%), but also achieves a reaction selectivity of 100%, avoids the generation of by-products and the decomposition of diacetone alcohol, reduces the reaction energy consumption, and does not require subsequent separation of the product and separation and recovery of the catalyst.

[0004] However, in the above scheme, in the process of arranging a condenser at the top of the tower to condense and reflux the vaporized light component propanol, the extraction of water is not considered, so that the by-product water is completely refluxed into the tower, which may interfere with the reaction process, resulting in incomplete reaction of the propanol raw material, thereby reducing the yield of diacetone alcohol in the scheme; on the other hand, in the process of fractionating the mixture of diacetone alcohol and water by the built-in reboiler in the above scheme, due to the incomplete vaporization of water and the condensation and reflux of water vapor after rising, it is difficult to achieve effective separation of diacetone alcohol and water, thereby making it difficult for the diacetone alcohol in the scheme to achieve the expected product purity. Summary of the invention

[0005] The object of the present invention is to provide a continuous reaction distillation equipment for synthesizing diacetone alcohol, which has the advantages of cyclic reaction and staged separation and solves the problems in the background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a continuous reaction and distillation equipment for synthesizing diacetone alcohol, comprising a distillation tower, an opening and closing mechanism, a condensing mechanism and a rotating mechanism, one side of the distillation tower is connected with a feed pipe, and the interior of the distillation tower is sequentially provided with a reaction section three, a reaction section two, a reaction section one, a stripping section and a reboiler from top to bottom, the reaction section one, the reaction section two and the reaction section three are sequentially fixedly connected and are connected to the inner wall of the distillation tower in a limited rotation manner, the feed pipe is unidirectionally connected to the reaction section one, the stripping section and the reboiler are fixedly connected and are fixedly connected to the inner wall of the distillation tower, the bottom end of the distillation tower is penetrated by a withdrawal pipe and the reboiler is unidirectionally connected to the withdrawal pipe; The opening and closing mechanism is arranged at the top of the distillation tower, and the opening and closing mechanism includes a flow guide fixedly connected to the outer periphery of the upper surface of the reaction section three and a pressure sensor fixedly connected to the center of the upper surface of the reaction section three; The condensing mechanism comprises a condensing group arranged on one side of the outside of the distillation tower, wherein the condensing group is provided with a condenser 1 and a condenser 2, and the condenser 1 is unidirectionally connected to the condenser 2, a gas phase pipe is unidirectionally connected from the top of the distillation tower to the condenser 1, and a reflux pipe that runs through the side of the distillation tower is unidirectionally connected from the condenser 2 to the reaction section 1; The rotating mechanism realizes uniform distribution of the liquid phase in the reaction section and sufficient mixing of the liquid phase in the bottom of the tower, and comprises a fixed ring penetrating and fixedly connected to the center of the stripping section; The absolute operating pressure of the distillation tower is 20-25 kPa, the tower top temperature is 60-65°C, the tower bottom temperature is 90-100°C, and the distillation tower space velocity is: ; The reaction section one, the reaction section two and the reaction section three are combined into a reaction section, the temperature of the reaction section is 70-80°C, the reaction section is filled with a catalytic filler, and the catalyst in the catalytic filler is a hydroxide-type macroporous alkaline resin, the reaction section one is filled with 828 resin, and the reaction sections two and three are filled with D296 resin.

[0007] Preferably, the opening and closing mechanism further comprises a sealing plate 1 arranged at the top of the flow guide cover and the sealing plate 1 is fixedly connected to the inner wall of the distillation tower, the upper surface limit of the sealing plate 1 is penetrated by four positioning shafts which are arranged around at equal intervals, the tops of the four positioning shafts are penetrated by the same sealing plate 2 and the sealing plate 2 is fixedly connected to the inner wall of the distillation tower, the middle sections of the four positioning shafts are fixedly connected to opening and closing arms and the four opening and closing arms are spliced ​​with each other, and the outer contour of the opening and closing arm is meshingly connected to a gear ring located between the sealing plate 1 and the sealing plate 2; The outer contour of the gear ring is meshingly connected with a driving wheel located outside the distillation tower. A protection frame is provided on the outer contour of the driving wheel and the protection frame is fixedly connected to the outer wall of the distillation tower. An adjustment shaft is fixedly connected to the center of the driving wheel and the adjustment shaft passes through the protection frame and extends upward.

[0008] Preferably, a gas phase hole matching the contour of the top end of the air guide cover is opened at the center of the sealing plate 1 and the sealing plate 2, and the adjustment shaft is driven by an external motor, and the external motor is electrically connected to the pressure sensor through a signal.

[0009] Preferably, the temperature of the condenser 1 is set to 50-55°C, and the temperature of the condenser 2 is set to 0-10°C.

[0010] Preferably, the rotating mechanism also includes a cross shaft fixedly connected to the inner contour of the fixed ring, the top end of the cross shaft passes through a bevel gear 1 that is rotatably connected and the bevel gear 1 is fixedly connected to the lower surface of the reaction section 1, both sides of the cross shaft pass through bevel gear 2 that is rotatably connected with opposite directions, the bottom end of the cross shaft passes through a bevel gear 3 that is rotatably connected, the bottom end of the bevel gear 3 is fixedly connected to a differential and the differential is rotatably connected to the center of the distillation section, the bottom end of the differential is fixedly connected to a rotating shaft, and blades are provided on the outer contour of the rotating shaft.

[0011] Preferably, the two bevel gears 2 are meshingly connected with bevel gear 1 and bevel gear 3, the rotating shaft and the paddles are located inside the reboiler, the bevel gear 1 is driven by a built-in low-speed motor, the rotation speed of the bevel gear 1 is 1 to 5 rpm, the amplification ratio of the differential is 1 to 50, and the rotation speed of the rotating shaft is 50 to 250 rpm.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides an opening and closing mechanism, and under the premise of not affecting the operating pressure in the distillation tower, by adjusting the gas phase flow to prolong the residence time of propanol in the reaction section, thereby improving the conversion rate and ensuring that the propanol raw material is fully reacted to increase the output of the device; 2. The present invention increases the discharge path of by-product water by providing a condensation mechanism, further reduces the reflux of water and thus reduces its interference with the reaction process, while effectively improving the product purity of diacetone alcohol; 3. The present invention realizes the coaxial reversal between the reaction section and the reboiler by providing a rotating mechanism, while ensuring the uniform distribution of the liquid phase during the reflux of propanol, promoting the mixing of the liquid phase by stirring to further improve the separation efficiency of diacetone alcohol and water, thereby reducing its residence time in the high temperature area to reduce the occurrence of side reactions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1It is a schematic diagram of the main structure of the present invention; Figure 2 It is a cross-sectional view of the main structure of the present invention; Figure 3 It is a cross-sectional view of the distillation tower structure of the present invention; Figure 4 It is a schematic diagram of the position of the opening and closing mechanism of the present invention; Figure 5 This is an exploded view of the opening and closing mechanism of the present invention; Figure 6 It is a schematic diagram of the condensation mechanism of the present invention; Figure 7 It is a schematic diagram of the position of the rotating mechanism of the present invention; Figure 8 It is a partial schematic diagram of the rotating mechanism of the present invention; Fig. 9 It is a partial cross-sectional view of the rotating mechanism of the present invention.

[0014] In the figure: 1. distillation tower; 11. feed pipe; 12. reaction section 1; 13. reaction section 2; 14. reaction section 3; 15. stripping section; 16. reboiler; 17. extraction pipe; 2. guide cover; 21. pressure sensor; 22. sealing plate 1; 23. sealing plate 2; 24. gear ring; 25. positioning shaft; 26. opening and closing arm; 27. driving wheel; 28. protection frame; 29. ​​adjusting shaft; 3. condensation group; 31. gas phase pipe; 32. condenser 1; 33. condenser 2; 34. reflux pipe; 35. discharge pipe; 4. fixing ring; 41. cross shaft; 42. bevel gear 1; 43. bevel gear 2; 44. bevel gear 3; 45. differential; 46. rotating shaft; 47. blade. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] For example, see Figures 1 to 9The present invention provides a technical solution: a continuous reaction and distillation equipment for synthesizing diacetone alcohol, comprising a distillation tower 1, an opening and closing mechanism, a condensing mechanism and a rotating mechanism, characterized in that: a feed pipe 11 is connected to one side of the distillation tower 1, and a reaction section three 14, a reaction section two 13, a reaction section one 12, a stripping section 15 and a reboiler 16 are sequentially arranged inside the distillation tower 1 from top to bottom, the reaction section one 12, the reaction section two 13 and the reaction section three 14 are sequentially fixedly connected and are connected to the inner wall of the distillation tower 1 in a limited rotation manner, the feed pipe 11 is unidirectionally connected to the reaction section one 12, the stripping section 15 and the reboiler 16 are fixedly connected and are fixedly connected to the inner wall of the distillation tower 1, and a withdrawal pipe 17 is passed through the bottom end of the distillation tower 1 and the reboiler 16 is unidirectionally connected to the withdrawal pipe 17; The opening and closing mechanism is arranged at the top of the distillation tower 1, and the opening and closing mechanism includes a flow guide 2 fixedly connected to the outer periphery of the upper surface of the reaction section three 14 and a pressure sensor 21 fixedly connected to the center of the upper surface of the reaction section three 14; The rotating mechanism realizes uniform distribution of the liquid phase in the reaction section and sufficient mixing of the liquid phase in the bottom of the tower, and comprises a fixed ring 4 penetrating and fixedly connected to the center of the stripping section 15; The absolute operating pressure of the distillation tower 1 is 20-25 kPa, the tower top temperature is 60-65°C, the tower bottom temperature is 90-100°C, and the space velocity of the distillation tower 1 is: ; The reaction section one 12, the reaction section two 13 and the reaction section three 14 are combined into a reaction section, the temperature of the reaction section is 70-80°C, the reaction section is filled with catalytic fillers and the catalyst in the catalytic fillers is a hydroxide-type macroporous alkaline resin, the reaction section one 12 is filled with 828 resin, and the reaction section two 13 and the reaction section three 14 are filled with D296 resin.

[0017] In this scheme, propanol enters the middle section of the distillation tower 1 through the feed pipe 11, and after entering the reaction section 12, it is vaporized under the heating action of the reboiler 16 and starts to react under the action of the catalyst, wherein the high catalytic activity of 828 resin is utilized in the reaction section 12 to quickly initiate the condensation reaction of propanol, the high selectivity of D296 resin is utilized in the reaction section 2 13 to promote the further conversion of the intermediate product into diacetone alcohol, and the deep reaction is further completed in the reaction section 3 14 to ensure that the reactants are fully converted.

[0018] It should be noted that the total height of the reaction section is 4 to 6 meters, of which the height of reaction section one 12 is 1.5 to 2.5 meters, accounting for 30% to 40% of the total height of the reaction section; the height of reaction section two 13 is 1.5 to 2.5 meters, accounting for 30% to 40% of the total height of the reaction section; the height of reaction section three 14 is 1 to 2 meters, accounting for 20% to 30% of the total height of the reaction section.

[0019] During this process, the gas phase pressure near the top of the distillation tower 1 is monitored in real time through the opening and closing mechanism, and the connection state between the distillation tower 1 and the condensing mechanism is controlled by setting the pressure threshold. When the gas phase pressure at the top of the distillation tower 1 exceeds the threshold, the opening and closing mechanism automatically opens to release excess gas phase and reduce the pressure in the tower; when the gas phase pressure at the top of the distillation tower 1 does not reach the threshold, the opening and closing mechanism remains closed to increase the gas phase residence time and improve the reaction efficiency; that is, the opening and closing mechanism prolongs the residence time of propanol in the reaction section by adjusting the gas phase flow, ensuring its full reaction to improve the conversion rate of the scheme.

[0020] It should be noted that, since the absolute operating pressure of the distillation tower 1 is 20-25 kPa, the tower top temperature is 60-65°C, and the temperature of the reaction section is 70-80°C. Under the low pressure environment of 20-25 kPa, the boiling point of water is 60-65°C, the boiling point of propanol is 40-45°C, and the boiling point of diacetone alcohol is 100-105°C, that is, the gas phase composition at the tower top is a mixture of water vapor and vaporized propanol, and diacetone alcohol flows downward in a liquid state and is finally extracted from the tower bottom.

[0021] The gaseous mixture at the top of the tower further enters the condensing mechanism through the opening and closing mechanism, and is separated from the propanol by segmented condensation in the condensing mechanism, wherein the water is discharged, and the propanol flows back into the reaction section 12 in a liquid state to react again, thereby fully ensuring the conversion rate of the scheme, reducing the interference of the by-product water on the reaction process and improving the product purity of diacetone alcohol.

[0022] On the other hand, the reaction section is slowly rotated by a rotating mechanism, and the slow rotation rate of the reaction section is synchronized with the rotation speed of the top of the rotating mechanism to be 1 to 5 rpm. Along with the slow rotation of the reaction section, the positions of the liquid propanol in the feed pipe 11 and the reflux pipe 34 change synchronously when entering the reaction section 12, thereby preventing the liquid propanol from accumulating on one side of the reaction section 12 during the period of time after entering the reaction section 12 but not yet vaporized. By ensuring uniform distribution of the liquid phase in the reaction section 12, local excessive concentration or incomplete reaction can be avoided, thereby improving the reaction efficiency of the scheme.

[0023] During the reaction, the liquid phase diacetone alcohol will entrain part of propanol and water when falling, and the propanol in the liquid phase will be vaporized and separated by heating in the distillation section 15, and then the water will be further evaporated and separated in the reboiler 16 to obtain high-purity diacetone alcohol; in this process, the rotating mechanism synchronously rotates and stirs the liquid phase in the reboiler 16, and the stirring accelerates the flow of the liquid phase, accelerates the evaporation of water to promote the separation of diacetone alcohol and water, reduces the residence time of diacetone alcohol in the high temperature area, and reduces the decomposition risk; at the same time, stirring can evenly distribute the heat in the reboiler 16, avoid local overheating and cause side reactions, and thus improve the purity of the product.

[0024] In the traditional reactive distillation process, the conversion rate of propanol is usually 90-95%, the purity of diacetone alcohol is about 95-98%, and there are many by-products. This scheme can effectively improve the conversion rate of propanol and the purity of diacetone alcohol through the reflux design of segmented condensation, the coaxial reverse stirring of the rotating mechanism, and the gas phase retention setting of the opening and closing mechanism, combined with segmented catalysis and low-pressure environment operation. The optimized propanol conversion rate can reach more than 99%, the purity of diacetone alcohol can reach more than 99%, and the by-products are reduced by more than 95%, and the energy consumption is reduced by 20-30%.

[0025] In the second embodiment, the opening and closing mechanism further comprises a sealing plate 22 arranged at the top of the flow guide 2, and the sealing plate 22 is fixedly connected to the inner wall of the distillation tower 1. The upper surface of the sealing plate 22 is limitedly penetrated by four positioning shafts 25 which are arranged around at equal intervals. The tops of the four positioning shafts 25 are penetrated by the same sealing plate 23, and the sealing plate 23 is fixedly connected to the inner wall of the distillation tower 1. The middle sections of the four positioning shafts 25 are fixedly connected to opening and closing arms 26, and the four opening and closing arms 26 are spliced ​​with each other. The outer contour of the opening and closing arm 26 is meshingly connected to a gear ring 24 located between the sealing plate 22 and the sealing plate 23. The outer contour of the gear ring 24 is meshingly connected to a driving wheel 27 located outside the distillation tower 1. A protection frame 28 is provided on the outer contour of the driving wheel 27 and the protection frame 28 is fixedly connected to the outer wall of the distillation tower 1. An adjustment shaft 29 is fixedly connected to the center of the driving wheel 27 and the adjustment shaft 29 passes through the protection frame 28 and extends upward.

[0026] The centers of the sealing plates 1 22 and 23 are both provided with gas phase holes adapted to the top contour of the air deflector 2 . The adjustment shaft 29 is driven by an external motor, and the external motor is electrically connected to the pressure sensor 21 via a signal.

[0027] It can be seen from Example 1 that the opening and closing mechanism prolongs the residence time of propanol in the reaction section by adjusting the gas phase flow. The alarm threshold is pre-set for the pressure sensor 21 before the device starts working. During the reaction process, the gas phase entering the guide cover 2 through the reaction section gradually increases, and the opening and closing mechanism is in a closed state at this time, resulting in the pressure value monitored by the pressure sensor 21 gradually increasing. When the pressure value exceeds the alarm threshold, the pressure sensor 21 sends a signal to the external motor of the adjusting shaft 29 and controls the adjusting shaft 29 to rotate. The adjusting shaft 29 further drives the driving wheel 27 and the ring gear 24 to rotate synchronously. The rotation of the ring gear 24 further causes the opening and closing arm 26 to deflect with the positioning shaft 25 as the axis, and the movement of the four opening and closing arms 26 is synchronized. At this time, the spliced ​​state of the four opening and closing arms 26 is in contact, and gaps appear between the four opening and closing arms 26, thereby removing the obstruction of the gas phase holes of the sealing plate 1 22 and the sealing plate 2 23. At this time, the mixture of vaporized propanol and water vapor gathered at the guide cover 2 enters the condensation mechanism through the gas phase hole, and the pressure value monitored by the pressure sensor 21 begins to decrease.

[0028] When the pressure value drops below the alarm threshold, the pressure sensor 21 sends a closing signal to the adjusting shaft 29, and the adjusting shaft 29 reverses to drive the driving wheel 27 and the ring gear 24 to reverse synchronously. At this time, the opening and closing arms 26 begin to reset with the positioning shaft 25 as the axis, and the four opening and closing arms 26 are reassembled and the blocking and sealing operation of the gas phase holes of the sealing plate 1 22 and the sealing plate 2 23 is completed. In the closed state, the mixture of vaporized propanol and water vapor stays in the reaction section three 14 and fully reacts under the action of the catalyst in the reaction section three 14, thereby effectively improving the conversion rate of the scheme.

[0029] On the other hand, the size of the opening and closing gaps between the four opening and closing arms 26 directly determines the flow rate of the gas phase from the distillation tower 1 into the condensation mechanism. By placing the adjustment shaft 29 and the drive wheel 27 outside the distillation tower 1, it is convenient for personnel to manually calibrate the gas phase flow rate.

[0030] In the third embodiment, the condensation mechanism comprises a condensation group 3 arranged on one side of the outside of the distillation tower 1, wherein a condenser 1 32 and a condenser 2 33 are arranged inside the condensation group 3, and the condenser 1 32 is unidirectionally connected to the condenser 2 33, a gas phase pipe 31 is unidirectionally connected from the top of the distillation tower 1 to the condenser 1 32, and a reflux pipe 34 that runs through the side of the distillation tower 1 is unidirectionally connected from the condenser 2 33 to the reaction section 1 12; The temperature of the condenser 1 32 is set to 50-55°C, and the temperature of the condenser 2 33 is set to 0-10°C.

[0031] It can be seen from Example 1 and Example 2 that the gas phase entering the condensing mechanism is a mixture of vaporized propanol and water vapor. At this time, the gas phase enters the condenser 32 through the gas phase pipe 31. Since the condensing mechanism is in a connected state with the distillation tower 1, that is, the condensing mechanism is also in a low-pressure environment of 20 to 25 kPa, the temperature of the condenser 32 is 50 to 55°C at this time, which can effectively condense the water vapor while keeping the propanol in a vaporized state, thereby realizing the separation of propanol and water. After separation, the liquid water is discharged to the outside through the discharge pipe 35, and the vaporized propanol enters the condenser 33 and is condensed into a liquid phase and refluxes into the reaction section 12 along the reflux pipe 34 to start the reaction again.

[0032] It should be noted that corresponding control valves are provided on the feed pipe 11, the discharge pipe 35 and the extraction pipe 17 to maintain a low pressure environment of 20-25 kPa inside the distillation tower 1 and the condensation mechanism.

[0033] In the fourth embodiment, the rotating mechanism further comprises a cross shaft 41 fixedly connected to the inner contour of the fixing ring 4, the top end of the cross shaft 41 penetrates and is rotatably connected to a bevel gear 1 42, and the bevel gear 1 42 is fixedly connected to the lower surface of the reaction section 12, both sides of the cross shaft 41 penetrate and are rotatably connected to a bevel gear 2 43 with opposite directions, the bottom end of the cross shaft 41 penetrates and is rotatably connected to a bevel gear 3 44, the bottom end of the bevel gear 3 44 is fixedly connected to a differential 45, and the differential 45 is rotatably connected to the center of the distillation section 15, the bottom end of the differential 45 is fixedly connected to a rotating shaft 46, and the outer contour of the rotating shaft 46 is provided with paddles 47.

[0034] The two bevel gears 2 43 are meshed and connected with bevel gear 1 42 and bevel gear 3 44. The rotating shaft 46 and the paddle 47 are located inside the reboiler 16. The bevel gear 1 42 is driven by a built-in low-speed motor. The rotation speed of the bevel gear 1 42 is 1 to 5 rpm. The amplification ratio of the differential 45 is 1 to 50, and the rotation speed of the rotating shaft 46 is 50 to 250 rpm.

[0035] As can be seen from the first embodiment, the rotating mechanism drives the reaction section to rotate slowly while completing the stirring of the liquid phase in the reboiler 16. The reaction section 12 rotates slowly to ensure that the liquid propanol that has not yet been vaporized is evenly distributed therein to improve the reaction efficiency and ensure that the propanol reacts fully. At the same time, the liquid phase in the reboiler 16 is stirred to accelerate the evaporation of water, reduce the residence time of diacetone alcohol in the high temperature area, and avoid its decomposition or the occurrence of side reactions.

[0036] When the device starts working, bevel gear 42 starts to rotate under the drive of its built-in low-speed motor. Since bevel gear 42 is fixedly connected to reaction section 12, reaction section 12, reaction section 2 13 and reaction section 3 14 are fixedly connected in sequence, that is, bevel gear 42 starts to drive the entire reaction section to rotate synchronously at a low speed. The rotation speed of the entire reaction section is synchronized to 1 to 5 rpm, which is dynamically adjusted within a set range according to the continuous input amount of propanol. The low-speed rotation of reaction section 12 causes the positions of liquid propanol in feed pipe 11 and reflux pipe 34 to change synchronously when entering reaction section 12, thereby avoiding excessive local concentration or incomplete reaction caused by uneven distribution of liquid phase in reaction section 12.

[0037] At the same time, the rotation of bevel gear one 42 drives bevel gear three 44 to rotate synchronously under the transmission action of bevel gear two 43, and the rotation direction of bevel gear three 44 is opposite to that of bevel gear one 42. The rotation of bevel gear three 44 further drives rotating shaft 46 to rotate synchronously through differential 45, and after amplification by differential 45, the speed ratio between bevel gear three 44 and rotating shaft 46 reaches 1:50, and rotating shaft 46 further drives paddle 47 to rotate. At this time, the speed of rotating shaft 46 and paddle 47 reaches 50-250rpm, and paddle 47 realizes sufficient stirring of the liquid phase in reboiler 16, and the separated high-purity diacetone alcohol is discharged through extraction pipe 17 for collection.

[0038] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A continuous reaction distillation device for synthesizing diacetone alcohol, comprising a distillation tower (1), characterized in that: The distillation tower (1) further comprises an opening and closing mechanism, a condensing mechanism and a rotating mechanism. A feed pipe (11) is connected to one side of the distillation tower (1). A reaction section three (14), a reaction section two (13), a reaction section one (12), a stripping section (15) and a reboiler (16) are arranged in sequence from top to bottom inside the distillation tower (1). The reaction section one (12), the reaction section two (13) and the reaction section three (14) are fixedly connected in sequence and are connected to the inner wall of the distillation tower (1) in a limited rotation manner. The feed pipe (11) is connected to the reaction section one (12) in one direction. The stripping section (15) and the reboiler (16) are fixedly connected and are fixedly connected to the inner wall of the distillation tower (1). A withdrawal pipe (17) is passed through the bottom end of the distillation tower (1) and the reboiler (16) is connected to the withdrawal pipe (17) in one direction. The opening and closing mechanism is arranged at the top of the distillation tower (1), and comprises a flow guide cover (2) fixedly connected to the outer periphery of the upper surface of the reaction section three (14) and a pressure sensor (21) fixedly connected to the center of the upper surface of the reaction section three (14); The condensing mechanism comprises a condensing group (3) arranged on one side of the outside of the distillation tower (1), wherein a condenser 1 (32) and a condenser 2 (33) are arranged inside the condensing group (3), and the condenser 1 (32) is connected to the condenser 2 (33) in one direction, a gas phase pipe (31) is connected to the top of the distillation tower (1) in one direction to the condenser 1 (32), and a reflux pipe (34) that runs through the side of the distillation tower (1) is connected to the condenser 2 (33) in one direction to the reaction section 1 (12); The rotating mechanism realizes uniform distribution of the liquid phase in the reaction section and sufficient mixing of the liquid phase in the bottom of the tower, and comprises a fixed ring (4) penetrating through and fixedly connected to the center of the stripping section (15); The absolute operating pressure of the distillation tower (1) is 20-25 kPa, the tower top temperature is 60-65°C, the tower bottom temperature is 90-100°C, and the space velocity of the distillation tower (1) is: ; The reaction section one (12), the reaction section two (13) and the reaction section three (14) are combined into a reaction section. The temperature of the reaction section is 70 to 80°C. The reaction section is filled with a catalytic filler and the catalyst in the catalytic filler is a hydroxide-type macroporous alkaline resin. The reaction section one (12) is filled with 828 resin, and the reaction section two (13) and the reaction section three (14) are filled with D296 resin.

2. The continuous reactive distillation equipment for synthesizing diacetone alcohol according to claim 1, characterized in that: The opening and closing mechanism further comprises a sealing plate 1 (22) arranged at the top of the flow guide cover (2), and the sealing plate 1 (22) is fixedly connected to the inner wall of the distillation tower (1); the upper surface of the sealing plate 1 (22) is limitedly penetrated by four positioning shafts (25) which are arranged around at equal intervals; the tops of the four positioning shafts (25) are penetrated by the same sealing plate 2 (23), and the sealing plate 2 (23) is fixedly connected to the inner wall of the distillation tower (1); the middle sections of the four positioning shafts (25) are fixedly connected to opening and closing arms (26), and the four opening and closing arms (26) are spliced ​​with each other; the outer contour of the opening and closing arm (26) is meshingly connected to a gear ring (24) located between the sealing plate 1 (22) and the sealing plate 2 (23); The outer contour of the gear ring (24) is meshingly connected to a driving wheel (27) located outside the distillation tower (1); a protection frame (28) is provided on the outer contour of the driving wheel (27), and the protection frame (28) is fixedly connected to the outer wall of the distillation tower (1); an adjustment shaft (29) is fixedly connected to the center of the driving wheel (27), and the adjustment shaft (29) passes through the protection frame (28) and extends upward.

3. The continuous reactive distillation equipment for synthesizing diacetone alcohol according to claim 2, characterized in that: The centers of the sealing plate 1 (22) and the sealing plate 2 (23) are both provided with gas phase holes adapted to the top profile of the air guide cover (2). The adjustment shaft (29) is driven by an external motor, and the external motor is connected to the pressure sensor (21) via a signal.

4. The continuous reactive distillation equipment for synthesizing diacetone alcohol according to claim 1, characterized in that: The temperature of the condenser 1 (32) is set to 50-55°C, and the temperature of the condenser 2 (33) is set to 0-10°C.

5. The continuous reactive distillation equipment for synthesizing diacetone alcohol according to claim 1, characterized in that: The rotating mechanism further comprises a cross shaft (41) fixedly connected to the inner contour of the fixing ring (4); the top end of the cross shaft (41) is penetrated by a bevel gear 1 (42) and is rotatably connected thereto, and the bevel gear 1 (42) is fixedly connected to the lower surface of the reaction section 1 (12); both sides of the cross shaft (41) are penetrated by a bevel gear 2 (43) with opposite directions and is rotatably connected thereto; the bottom end of the cross shaft (41) is penetrated by a bevel gear 3 (44) and is rotatably connected thereto; the bottom end of the bevel gear 3 (44) is fixedly connected to a differential (45) and the differential (45) is rotatably connected to the center of the stripping section (15); the bottom end of the differential (45) is fixedly connected to a rotating shaft (46), and a blade (47) is provided on the outer contour of the rotating shaft (46).

6. The continuous reactive distillation equipment for synthesizing diacetone alcohol according to claim 5, characterized in that: The two bevel gears 2 (43) are meshed and connected with bevel gear 1 (42) and bevel gear 3 (44). The rotating shaft (46) and the blades (47) are located inside the reboiler (16). The bevel gear 1 (42) is driven by a built-in low-speed motor. The rotation speed of the bevel gear 1 (42) is 1 to 5 rpm. The amplification ratio of the differential (45) is 1 to 50. The rotation speed of the rotating shaft (46) is 50 to 250 rpm.

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