Rectification equipment and rectification system for MIBK (methyl isobutyl ketone) rectification

Abstract

The utility model discloses rectification equipment and a rectification system for MIBK (methyl isobutyl ketone) rectification, and belongs to the technical field of chemical rectification. The rectification equipment for MIBK rectification comprises a rectification tower, the rectification tower comprises a tower body of a cylindrical barrel structure, and vertical partition plates are arranged in the tower body and divide the rectification tower into a pre-fractionation section, a rectification section, a stripping section and a middle discharging section. By adopting the rectifying tower, an MIBK solution which is from an MIBK light component removal system and does not contain light components but contains heavy components and water can be rectified and separated. Removing organic water in the rectifying section of the rectifying tower; heavy components are removed at a stripping section of the rectifying tower; a target product-MIBK is obtained at a middle discharging section of the rectifying tower. By utilizing the rectifying tower, the quantity of equipment can be reduced, the process flow is simplified, the device investment is reduced, the raw material and energy consumption in production is reduced, the production cost is reduced, and the carbon emission of a production device is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical distillation, in particular to distillation equipment and a distillation system for MIBK distillation. Background Art

[0002] MIBK chemical name methyl isobutyl ketone, also known as 4-methyl-2-pentanone, is an organic compound with the chemical formula C6H 12 O, mainly used as a solvent for spray paint, nitrocellulose, certain cellulose ethers, camphor, oils and fats, natural and synthetic rubber.

[0003] In the MIBK light component removal system, the MIBK solution containing the light components contains water and heavy components, with water reaching nearly 30% and heavy components reaching nearly 2%. These components must be removed to prevent the quality of the MIBK product from being compromised. Existing MIBK production typically utilizes a two-step distillation process. Step 1: The MIBK solution, after the light components have been removed, is first phase-separated. The oil-phase produced liquid is distilled through a dehydration tower to produce an azeotrope, which is then condensed and phase-separated to remove the remaining water. Step 2: The bottoms liquid from step 1 is fed into a MIBK product tower for distillation to separate the MIBK product. The MIBK product separated by dehydration and distillation is recovered through two distillation separation and recovery systems. Distillation separation is the most mature and widely used separation technology in chemical production, but the distillation process consumes significant energy. Over 50% of the energy consumed in chemical production is used for separation, and distillation accounts for 95% of this energy consumption.

[0004] Therefore, it is necessary to improve the existing MIBK distillation equipment, and it is urgent to provide a distillation equipment for MIBK distillation with a short process, small footprint, low investment and low energy consumption. Utility Model Content

[0005] The purpose of the utility model is to provide a distillation device and a distillation system for MIBK distillation with a short process, small footprint, low investment and low energy consumption, so as to solve the technical problem that the MIBK distillation in the prior art requires two sets of distillation equipment and has high energy consumption.

[0006] The distillation equipment for MIBK distillation of the present invention adopts the following technical solution: a distillation equipment for MIBK distillation, which includes a distillation tower, which includes a tower body with a cylindrical barrel structure, a vertical partition plate is provided in the middle of the tower body, and the partition plate extends up and down, a MIBK produced liquid feed inlet C is provided on the side of the middle of the tower body, an azeotrope outlet A is provided on the top, a tower bottom liquid outlet G is provided at the bottom, and a MIBK outlet D is provided on the side of the middle, the MIBK produced liquid feed inlet C and the MIBK outlet D are respectively located on both sides of the partition plate; the area between the top of the partition plate in the tower body and the azeotrope outlet A is used as a distillation section, the area between the bottom end of the partition plate in the tower body and the bottom tower bottom liquid outlet G is used as a stripping section, and the area between the partition plate in the tower body and the MIBK produced liquid outlet G is used as a stripping section. The portion between the liquid feed ports C serves as a pre-fractionation section, and the portion between the partition plate in the tower body and the MIBK outlet D serves as an intermediate discharging section; the pre-fractionation section is provided with a pre-fractionation section rectifying layer and a pre-fractionation section stripping layer spaced apart in an upper and lower manner, and the MIBK produced liquid feed port C is located between the pre-fractionation section rectifying layer and the pre-fractionation section stripping layer; the intermediate discharging section is provided with an intermediate discharging section rectifying layer and an intermediate discharging section stripping layer spaced apart in an upper and lower manner, and the MIBK outlet D is located between the intermediate discharging section rectifying layer and the intermediate discharging section stripping layer; the rectifying section is provided with a rectifying section rectifying layer, and a gap is provided between the rectifying section rectifying layer and the partition plate; the stripping section is provided with a stripping section stripping layer, and a gap is provided between the stripping section stripping layer and the partition plate.

[0007] A MIBK produced liquid feed pipe connected to the MIBK produced liquid feed port C is provided in the tower body, a first liquid distributor is horizontally installed below the MIBK produced liquid feed pipe, and the MIBK produced liquid feed pipe and the first liquid distributor are both located between the pre-fractionation section rectifying layer and the pre-fractionation section stripping layer; a liquid discharge distributor connected to the MIBK outlet D is provided in the tower body, and the liquid discharge distributor is located between the intermediate discharge section rectifying layer and the intermediate discharge section stripping layer.

[0008] In the tower body, a horizontally arranged second liquid distributor is installed between the rectifying layer and the partition plate of the rectifying section. A gap is provided between the rectifying layer and the azeotrope outlet A of the rectifying section. An oil phase reflux port B is provided on the side wall of the gap. A calandria-type liquid distributor is horizontally installed at the oil phase reflux port B. The MIBK solution is refluxed sequentially through the azeotrope outlet A and the oil phase reflux port B.

[0009] In the tower body, a third liquid distributor is installed horizontally between the stripping layer and the partition plate of the stripping section; there is a gap between the stripping layer of the stripping section and the bottom liquid outlet G, and a steam reflux port E and a bottom liquid side wall outlet F are provided on the side wall of the gap. The steam reflux port E is located above the bottom liquid side wall outlet F and an air inlet distributor is installed horizontally at the steam reflux port E. The MIBK vapor is refluxed through the bottom liquid side wall outlet F and the steam reflux port E in sequence.

[0010] The top of the distillation layer of the pre-fractionation section and the top of the distillation layer of the intermediate discharging section shall not be higher than the height of the top of the partition plate, and the ratio of the horizontal cross-sectional area of ​​the distillation layer of the pre-fractionation section to that of the distillation layer of the intermediate discharging section shall be 1:10~10:1; the bottom end of the stripping layer of the pre-fractionation section and the bottom end of the stripping layer of the intermediate discharging section shall not be lower than the height of the bottom end of the partition plate, and the ratio of the horizontal cross-sectional area of ​​the stripping layer of the pre-fractionation section to that of the stripping layer of the intermediate discharging section shall be 1:10~10:1; the distillation layer of the pre-fractionation section, the distillation layer of the intermediate discharging section, the stripping layer of the pre-fractionation section and the stripping layer of the intermediate discharging section are all packing layers with a height of 2~12 meters; the distillation layer of the distillation section is a packing layer with a height of 2~12 meters, and the stripping layer of the stripping section is a packing layer with a height of 2~12 meters.

[0011] A distillation system for MIBK distillation, comprising a distillation tower, the distillation tower comprising a cylindrical tower body, characterized in that: a vertical partition plate is provided in the middle of the tower body, the partition plate extending up and down, a MIBK produced liquid feed port C is provided on the side of the middle of the tower body, an azeotrope outlet A is provided at the top, a tower bottom liquid outlet G is provided at the bottom, and a MIBK outlet D is provided on the side of the middle, the MIBK produced liquid feed port C and the MIBK outlet D are respectively located on both sides of the partition plate; the area between the top of the partition plate and the azeotrope outlet A in the tower body serves as a distillation section, the area between the bottom of the partition plate and the bottom tower bottom liquid outlet G in the tower body serves as a stripping section, and the area between the partition plate and the MIBK produced liquid feed port C in the tower body As a pre-fractionation section, the portion between the partition plate and the MIBK outlet D in the tower body serves as an intermediate discharging section; the pre-fractionation section is provided with a pre-fractionation section rectifying layer and a pre-fractionation section stripping layer spaced apart from each other in upper and lower directions, and the MIBK produced liquid feed port C is located between the pre-fractionation section rectifying layer and the pre-fractionation section stripping layer; the intermediate discharging section is provided with an intermediate discharging section rectifying layer and an intermediate discharging section stripping layer spaced apart from each other in upper and lower directions, and the MIBK outlet D is located between the intermediate discharging section rectifying layer and the intermediate discharging section stripping layer; the rectifying section is provided with a rectifying section rectifying layer, and a gap is provided between the rectifying section rectifying layer and the partition plate; the stripping section is provided with a stripping section stripping layer, and a gap is provided between the stripping section stripping layer and the partition plate;

[0012] A raw material phase separator, a water phase extraction tank, an oil phase extraction tank, and a preheater are provided on the outside of the distillation tower. The raw material phase separator is provided with a middle inlet, an upper outlet, and a bottom outlet. The bottom outlet of the raw material phase separator is connected to the water phase extraction tank, the upper outlet of the raw material phase separator is connected to the upper inlet of the oil phase extraction tank, the inlet of the preheater is connected to the bottom outlet of the oil phase extraction tank, and the outlet of the preheater is connected to the MIBK produced liquid feed port C of the distillation tower.

[0013] The tower body is provided with a MIBK produced liquid feed pipe connected to the MIBK produced liquid feed port C, a first liquid distributor is horizontally installed below the MIBK produced liquid feed pipe, and the MIBK produced liquid feed pipe and the first liquid distributor are both located between the pre-fractionation section rectifying layer and the pre-fractionation section stripping layer; the tower body is provided with a liquid discharge distributor connected to the MIBK outlet D, and the liquid discharge distributor is located between the intermediate discharge section rectifying layer and the intermediate discharge section stripping layer; the bottom outlet of the water phase extraction tank is connected to an organic aqueous solution pipeline, and the organic aqueous solution pipeline is provided with an organic aqueous solution delivery pump; the pipeline between the oil phase extraction tank and the preheater is provided with a rectifying tower feed pump.

[0014] In the tower body, a horizontally arranged second liquid distributor is installed between the rectifying layer and the partition plate of the rectifying section. A gap is provided between the rectifying layer and the azeotrope outlet A of the rectifying section. An oil phase reflux port B is provided on the side wall of the gap. A calandria-type liquid distributor is horizontally installed at the oil phase reflux port B. The MIBK solution is refluxed sequentially through the azeotrope outlet A and the oil phase reflux port B.

[0015] A condenser and a phase separation reflux device are sequentially provided on the pipeline between the azeotrope outlet A and the oil phase reflux port B along the flow direction of the MIBK solution. The bottom of the phase separation reflux device is connected to the water phase extraction tank through a pipeline.

[0016] In the tower body, a horizontally arranged third liquid distributor is installed between the stripping layer of the stripping section and the partition plate; there is a gap between the stripping layer of the stripping section and the bottom liquid outlet G, and a steam reflux port E and a bottom liquid side wall outlet F are provided on the side wall of the gap. The steam reflux port E is located above the bottom liquid side wall outlet F and an air inlet distributor is horizontally installed at the steam reflux port E. The MIBK steam is refluxed in sequence through the bottom liquid side wall outlet F and the steam reflux port E. A reboiler is provided on the pipeline between the bottom liquid side wall outlet F and the steam reflux port E.

[0017] The beneficial effects of the present invention are as follows: the present invention distills and separates a MIBK solution from a MIBK light component removal system that contains no light components but heavy components and water. Unlike prior art distillation towers, the present invention incorporates a vertical partition plate within the distillation tower, resulting in a distillation tower comprising not only a distillation section and a stripping section, but also a pre-fractionation section and an intermediate discharge section. The distillation section of the distillation tower removes organic water; the stripping section of the distillation tower removes heavy components; and the intermediate discharge section of the distillation tower produces the target product, MIBK. In the distillation system of the present invention, the pretreatment section and the azeotropic distillation section recover the organic aqueous solution and return it to the MIBK light component removal system for extraction. The stripping section recovers the heavy components, separates the mixed liquid in the boundary zone, and recovers the heavy components. The intermediate discharge section recovers the target product, MIBK.

[0018] After light components are removed from the MIBK solution, the MIBK solution contains water and heavy components, with water reaching approximately 30% and heavy components approaching 2%. These components must be removed to prevent the quality of the MIBK product from being compromised. This patent provides a distillation device for MIBK fractionation. Using this device, water and heavy components can be effectively removed to yield a qualified target MIBK product.

[0019] The distillation tower of the utility model adopts a partition plate distillation tower to replace the dehydration tower and the MIBK product tower, combining the two distillation towers into one, while eliminating a condenser and a reboiler, saving about 30% of the investment in distillation equipment; MIBK appears at the top and bottom of the tower at the same time, and the composition of the raw materials entering the partition plate distillation tower can better match the composition on the liquid distributor of the pre-fractionation section, reducing the mixing effect at the liquid distributor, that is, reducing the mixing effect caused by the different compositions of the feed and the liquid distributor, meeting the requirements of the optimal feed liquid distributor, and improving thermodynamic efficiency. Since the heat of the partition plate distillation tower is repeatedly recycled in the same tower, the distillation energy consumption is also saved, and the energy consumption saved is about 30%. The distillation system of the utility model is safe, environmentally friendly, has a high yield of the target product, and low energy consumption. It has the advantages of energy saving and consumption reduction, reducing carbon emissions of production equipment, and protecting the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a diagram showing the working section division of a distillation equipment tower body for MIBK distillation in one embodiment of the present utility model;

[0021] Figure 2 This is a schematic diagram of a distillation equipment tower body for MIBK distillation according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic flow diagram of a distillation system for MIBK distillation according to an embodiment of the present invention;

[0023] Figure 4 This is the performance evaluation result table of a 10,000 ton / year MIBK distillation system.

[0024] Among them, 1. raw material phase separator, 2. water phase extraction tank, 3. organic water solution delivery pump, 4. oil phase extraction tank, 5. distillation tower feed pump, 6. preheater, 7. distillation tower, 7-1. MIBK produced liquid feed pipe, 7-2. first liquid distributor, 7-3. pre-fractionation section distillation layer, 7-4. pre-fractionation section stripping layer, 7-5. distillation section distillation layer, 7-6. second liquid distributor, 7-7. calandria liquid distributor, 7-8. stripping layer of stripping section, 7-9. third liquid distributor, 7-10. air inlet distributor, 7-11. intermediate discharge section distillation layer, 7-12. intermediate discharge section stripping layer, 7-13. liquid discharge distributor, 8. partition plate, 9. condenser, 10. phase separation reflux device, 11. reboiler. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are some embodiments of the present invention, not all embodiments. The components of the embodiments of the present invention generally described and illustrated in the drawings herein can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments derived by ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the drawings, where the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are illustrative and intended to explain the present invention, and should not be construed as limiting the present invention.

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] like Figures 1 to 2As shown, a distillation device for MIBK distillation according to an embodiment of the present invention includes a distillation tower, which can distill and separate a MIBK solution containing no light components but heavy components and water from a MIBK light component removal system; the distillation tower includes a tower body with a cylindrical barrel structure, a vertical partition plate 8 is provided in the tower body, a MIBK produced liquid feed inlet C is provided on the side of the middle part of the tower body of the distillation tower 7, an azeotrope outlet A is provided at the top, a bottom liquid outlet G is provided at the bottom, and a MIBK outlet D is provided on the side of the middle part, and the MIBK produced liquid feed inlet C and the MIBK outlet D are respectively located on both sides of the partition plate 8; the side of the MIBK produced liquid feed inlet C of the partition plate 8 in the tower body serves as a pre-fractionation section, the area above the partition plate 8 to the top azeotrope outlet A in the distillation tower 7 serves as a distillation section, the area below the partition plate 8 to the bottom liquid outlet G in the distillation tower 7 serves as a stripping section, and the side of the MIBK outlet D in the distillation tower 7 serves as an intermediate discharge section.

[0028] like Figure 1 、 2 The upper part of the pre-fractionation section is the pre-fractionation section distillation layer 7-3, and the lower part is the pre-fractionation section stripping layer 7-4; there is a gap between the pre-fractionation section distillation layer 7-3 and the pre-fractionation section stripping layer 7-4, and a MIBK produced liquid feed pipe 7-1 is horizontally installed at the MIBK produced liquid feed port C on the side wall of the gap, and a first liquid distributor 7-2 is horizontally installed below the MIBK produced liquid feed pipe 7-1.

[0029] like Figure 1 、 2 In the middle of the rectifying section is the rectifying layer 7-5 of the rectifying section. There is a gap between the rectifying layer 7-5 of the rectifying section and the partition plate 8. A second liquid distributor 7-6 is horizontally installed in the gap. There is a gap between the rectifying layer 7-5 of the rectifying section and the azeotrope outlet A. An oil phase reflux port B is provided on the side wall of the gap. A calandria-type liquid distributor 7-7 is horizontally installed at the oil phase reflux port B. The MIBK solution is refluxed through the azeotrope outlet A and the oil phase reflux port B in sequence.

[0030] like Figure 1 、 2 The middle part of the stripping section is the stripping layer 7-8 of the stripping section. There is a gap between the stripping layer 7-8 of the stripping section and the partition plate 8, and a third liquid distributor 7-9 is horizontally installed in the gap; there is a gap between the stripping layer 7-8 of the stripping section and the bottom liquid outlet G, and a steam reflux port E and a bottom liquid outlet F are provided on the side wall of the gap. The steam reflux port E is located above the bottom liquid outlet F and an air inlet distributor 7-10 is horizontally installed at the steam reflux port E. The MIBK vapor is refluxed through the bottom liquid outlet F and the steam reflux port E in turn.

[0031] like Figure 1 、 2The upper part of the middle discharge section is the middle discharge section distillation layer 7-11, and the lower part is the middle discharge section stripping layer 7-12. There is a gap between the middle discharge section distillation layer 7-11 and the middle discharge section stripping layer 7-12. A liquid discharge distributor 7-13 is horizontally installed in the gap. A MIBK outlet D is provided at the intersection of the liquid discharge distributor 7-13 and the side wall of the distillation tower 7.

[0032] like Figure 2 The top of the pre-fractionation section distillation layer 7-3 and the top of the intermediate discharging section distillation layer 7-11 are not higher than the top height of the partition plate 8, and the ratio of the horizontal cross-sectional areas of the pre-fractionation section distillation layer 7-3 and the intermediate discharging section distillation layer 7-11 is 1:1; the bottom end of the pre-fractionation section stripping layer 7-4 and the bottom end of the intermediate discharging section stripping layer 7-12 are not lower than the bottom end height of the partition plate 8, and the ratio of the horizontal cross-sectional areas of the pre-fractionation section stripping layer 7-4 and the intermediate discharging section stripping layer 7-12 is 1:1; the pre-fractionation section distillation layer 7-3 and the pre-fractionation section stripping layer 7-4 are both packing layers with a height of 2.5 meters; the intermediate discharging section distillation layer 7-11 and the intermediate discharging section stripping layer 7-12 are both packing layers with a height of 5.6 meters.

[0033] like Figure 2 The rectifying layer 7-5 of the rectifying section is a packing layer with a height of 2.8 meters, and the stripping layer 7-8 of the stripping section is a packing layer with a height of 2.8 meters.

[0034] The distillation system of MIBK distillation in one embodiment of the utility model is as follows Figure 3 As shown, it includes the distillation tower 7 in the above embodiment, and the distillation tower 7 is provided with a raw material phase separator 1, a water phase production tank 2, an oil phase production tank 4, a preheater 6, a phase separation reflux device 10, and a reboiler 11 on the outside. The raw material phase separator 1 is provided with a middle inlet, an upper outlet and a bottom outlet. The bottom outlet of the raw material phase separator 1 is connected to the water phase production tank 2, the upper outlet of the raw material phase separator 1 is connected to the upper inlet of the oil phase production tank 4, the inlet of the preheater 6 is connected to the bottom outlet of the oil phase production tank 4, and the outlet of the preheater 6 is connected to the MIBK produced liquid feed port C of the distillation tower.

[0035] The raw material from the MIBK light component removal system - the MIBK solution pipeline is connected to the middle inlet A of the raw material phase separator 1, the upper outlet B of the phase separator 1 is connected in sequence to the oil phase production tank 4, the distillation tower feed pump 5, the preheater 6 and the MIBK produced liquid feed inlet C on the middle side of the distillation tower 7, and the MIBK outlet D on the middle side of the distillation tower 7 is connected to the target product of the deboundary area - the MIBK transportation pipeline.

[0036] The bottom outlet C of the phase separator 1 is connected to the water phase extraction tank 2, the organic aqueous solution delivery pump 3 and the organic aqueous solution pipeline of the deboundary zone in sequence. The pipeline connecting the bottom outlet C of the phase separator 1 and the top inlet A of the water phase extraction tank 2 is provided with a pipeline from the bottom outlet C of the phase separator reflux device 10.

[0037] The azeotrope outlet A at the top of the distillation tower 7 is connected to the middle inlet A of the phase separator reflux device 10 through the condenser 9, and the upper outlet B of the phase separator reflux device 10 is connected to the oil phase reflux port B at the top of the distillation tower 7.

[0038] The bottom liquid outlet F of the distillation tower 7 is connected to the bottom inlet A of the reboiler 11, the top outlet B of the reboiler 11 is connected to the steam reflux port E of the distillation tower 7, and the bottom liquid outlet G of the distillation tower 7 is connected to the bottom liquid heavy component pipeline of the de-boundary zone.

[0039] The process flow of the distillation system for MIBK distillation in the above embodiment includes the following sections:

[0040] (1) Pretreatment section: the raw material from the MIBK light component removal system, i.e., the MIBK solution, enters the raw material phase separator 1 from the middle inlet A of the raw material phase separator 1 for phase separation, the organic aqueous solution enters the lower layer of the phase separator 1 and enters the water phase extraction tank 2 from the bottom outlet C of the phase separator 1, the organic aqueous solution from the phase separation reflux device 10 also enters the water phase extraction tank 2, the organic aqueous solution in the water phase extraction tank 2 is sent to the MIBK light component removal system in the boundary area by the organic aqueous solution delivery pump 3 for extraction; the MIBK enters the upper layer of the phase separator 1 and goes to the oil phase extraction tank 4 from the upper outlet B of the raw material phase separator 1, the MIBK produced liquid in the oil phase extraction tank 4 enters the preheater 6 through the distillation tower feed pump 5, the MIBK produced liquid is heated in the preheater 6 and then goes out of the preheater 6 to the distillation tower 7 for pre-fractionation section;

[0041] (2) Pre-fractionation section: The MIBK produced liquid from the pre-treatment section enters the distillation tower 7 from the MIBK produced liquid feed port C on the side of the middle part of the distillation tower 7 for pre-fractionation. After pre-fractionation, the MIBK produced liquid is converted into pre-fractionated MIBK; the mixed liquid of the pre-fractionated MIBK and the heavy components flows downward and is first distilled in the pre-fractionation section stripping layer 7-4, and then goes to the stripping section; the azeotropic gas of MIBK and water flows upward and is first distilled in the pre-fractionation section stripping layer 7-3, and then goes upward to the distillation section;

[0042] (3) Azeotrope distillation section: The azeotrope gas of MIBK and water from the pre-fractionation section of the distillation tower 7 is distilled in the distillation layer 7-5 of the distillation section, and heat and mass transfer is carried out with the oil phase refluxed from the oil phase reflux port B on the upper side of the distillation tower 7. The MIBK liquid flows downward and enters the middle discharge section. The azeotrope gas of MIBK and water after distillation flows upward and exits the distillation section of the distillation tower 7 from the azeotrope outlet A at the top of the distillation tower 7. It is condensed into liquid through the condenser 9 and then enters the phase separator reflux 10. In the phase separator reflux 10, MIBK and water are phase-separated. The organic aqueous solution enters the lower layer of the phase separator reflux 10 and is removed from the water phase extraction tank 2 from the bottom outlet C of the phase separator reflux 10. MIBK enters the upper layer of the phase separator reflux 10 and enters the distillation section of the distillation tower 7 as the oil phase from the upper outlet B of the phase separator reflux 10 through the oil phase reflux port B on the upper side of the distillation tower 7.

[0043] (4) Distillation section: The mixed liquid of MIBK and heavy components from the pre-fractionation section of the distillation tower 7 is stripped in the stripping layer 7-8 of the stripping section, and heat and mass transfer is carried out with the gas phase refluxed from the steam reflux port E at the lower side of the distillation tower 7. The MIBK gas after distillation flows upward into the middle discharge section, and the mixed liquid of heavy components flows downward. A part of the mixed liquid of heavy components is sent to the reboiler 11 from the side wall outlet F of the bottom liquid of the lower part of the distillation tower 7. In the reboiler 11, the mixed liquid is heated, and the MIBK in the mixed liquid is heated and evaporated into gas as the gas phase and enters the stripping section from the steam reflux port E at the lower part of the distillation tower 7. Another part of the mixed liquid of heavy components is sent to the boundary area from the bottom liquid outlet G at the bottom of the distillation tower 7 to separate and recover the heavy components.

[0044] (5) Intermediate discharging section: MIBK liquid flowing downward from the rectifying section of the rectifying tower 7 into the intermediate discharging section of the rectifying tower 7 is distilled in the rectifying layer 7-11 of the intermediate discharging section, and MIBK gas flowing upward from the stripping section of the rectifying tower 7 into the intermediate discharging section of the rectifying tower 7 is distilled in the stripping layer 7-12 of the intermediate discharging section. MIBK is purified in the intermediate discharging section and the purified MIBK is discharged as the target product from the MIBK outlet D on the side of the middle of the intermediate discharging section of the rectifying tower 7 to the boundary area.

[0045] The results of using the utility model to perform MIBK distillation are as follows: Figure 4 As shown in the table.

Claims

1. A distillation apparatus for MIBK distillation, comprising a distillation tower, the distillation tower comprising a tower body of a cylindrical barrel structure, characterized in that: A vertical partition plate (8) is provided in the middle of the tower body, and the partition plate (8) extends up and down. A MIBK produced liquid feed port C is provided on the side of the middle of the tower body, an azeotrope outlet A is provided on the top, a tower bottom liquid outlet G is provided on the bottom, and a MIBK outlet D is provided on the side of the middle. The MIBK produced liquid feed port C and the MIBK outlet D are respectively located on both sides of the partition plate (8); the area between the top of the partition plate (8) in the tower body and the azeotrope outlet A is used as a distillation section, the area between the bottom of the partition plate (8) in the tower body and the bottom tower bottom liquid outlet G is used as a stripping section, the area between the partition plate (8) in the tower body and the MIBK produced liquid feed port C is used as a pre-fractionation section, and the area between the partition plate (8) in the tower body and the MIBK outlet D is used as an intermediate discharge section; the pre-fractionation section is provided with an upper and lower intermediate section. A pre-fractionation section distillation layer (7-3) and a pre-fractionation section stripping layer (7-4) are provided at intervals, and the MIBK produced liquid feed port C is located between the pre-fractionation section distillation layer (7-3) and the pre-fractionation section stripping layer (7-4); the intermediate discharging section is provided with an intermediate discharging section distillation layer (7-11) and an intermediate discharging section stripping layer (7-12) which are provided at intervals up and down, and the MIBK outlet D is located between the intermediate discharging section distillation layer (7-11) and the intermediate discharging section stripping layer (7-12); the distillation section is provided with a distillation section distillation layer (7-5), and a gap is provided between the distillation section distillation layer (7-5) and the partition plate (8); the stripping section is provided with a stripping section stripping layer (7-8), and a gap is provided between the stripping section stripping layer (7-8) and the partition plate (8).

2. The distillation equipment for MIBK distillation according to claim 1, characterized in that: The tower body is provided with a MIBK produced liquid feed pipe (7-1) connected to a MIBK produced liquid feed port C, a first liquid distributor (7-2) is horizontally installed below the MIBK produced liquid feed pipe (7-1), and the MIBK produced liquid feed pipe (7-1) and the first liquid distributor (7-2) are both located between a pre-fractionation section rectifying layer (7-3) and a pre-fractionation section stripping layer (7-4); the tower body is provided with a liquid discharge distributor (7-13) connected to a MIBK outlet D, and the liquid discharge distributor (7-13) is located between a middle discharge section rectifying layer (7-11) and a middle discharge section stripping layer (7-12).

3. The distillation equipment for MIBK distillation according to claim 1, characterized in that: In the tower body, a horizontally arranged second liquid distributor (7-6) is installed between the rectifying layer (7-5) of the rectifying section and the partition plate (8); a gap is provided between the rectifying layer (7-5) of the rectifying section and the azeotrope outlet A; an oil phase reflux port B is provided on the side wall of the gap; a tube-type liquid distributor (7-7) is horizontally installed at the oil phase reflux port B; and the MIBK solution is refluxed sequentially through the azeotrope outlet A and the oil phase reflux port B.

4. The distillation equipment for MIBK distillation according to claim 1, characterized in that: In the tower body, a third liquid distributor (7-9) is installed horizontally between the stripping layer (7-8) of the stripping section and the partition plate (8); a gap is provided between the stripping layer (7-8) of the stripping section and the tower bottom liquid outlet G, a steam reflux port E and a tower bottom liquid side wall outlet F are provided on the side wall of the gap, the steam reflux port E is located above the tower bottom liquid side wall outlet F, and an air inlet distributor (7-10) is installed horizontally at the steam reflux port E, and the MIBK steam is refluxed in sequence through the tower bottom liquid side wall outlet F and the steam reflux port E.

5. The distillation equipment for MIBK distillation according to any one of claims 1 to 4, characterized in that: The top of the pre-fractionation section distillation layer (7-3) and the top of the middle discharge section distillation layer (7-11) are not higher than the top of the partition plate (8), and the ratio of the horizontal cross-sectional area of ​​the pre-fractionation section distillation layer (7-3) and the middle discharge section distillation layer (7-11) is 1:10~10:1; the bottom of the pre-fractionation section stripping layer (7-4) and the bottom of the middle discharge section stripping layer (7-12) are not lower than the bottom of the partition plate (8), and the pre-fractionation section stripping layer (7-4) and the middle discharge section stripping layer (7-12) are not lower than the bottom of the partition plate (8). The ratio of the horizontal cross-sectional areas of the stripping layer (7-12) of the discharge section is 1:10~10:1; the distillation layer (7-3) of the pre-fractionation section, the distillation layer (7-11) of the intermediate discharge section, the stripping layer (7-4) of the pre-fractionation section, and the stripping layer (7-12) of the intermediate discharge section are all packing layers with a height of 2~12 meters; the distillation layer (7-5) of the distillation section is a packing layer with a height of 2~12 meters, and the stripping layer (7-8) of the stripping section is a packing layer with a height of 2~12 meters.

6. A distillation system for MIBK distillation, comprising a distillation tower, the distillation tower comprising a tower body of a cylindrical barrel structure, characterized in that: A vertical partition plate (8) is provided in the middle of the tower body, and the partition plate (8) extends up and down. A MIBK produced liquid feed port C is provided on the side of the middle of the tower body, an azeotrope outlet A is provided on the top, a tower bottom liquid outlet G is provided on the bottom, and a MIBK outlet D is provided on the side of the middle. The MIBK produced liquid feed port C and the MIBK outlet D are respectively located on both sides of the partition plate (8); the area between the top of the partition plate (8) in the tower body and the azeotrope outlet A is used as a distillation section, the area between the bottom of the partition plate (8) in the tower body and the bottom tower bottom liquid outlet G is used as a stripping section, the area between the partition plate (8) in the tower body and the MIBK produced liquid feed port C is used as a pre-fractionation section, and the area between the partition plate (8) in the tower body and the MIBK outlet D is used as an intermediate discharge section; the pre-fractionation section is provided with an upper and lower intermediate section. A pre-fractionation section distillation layer (7-3) and a pre-fractionation section stripping layer (7-4) are provided at intervals, and the MIBK produced liquid feed port C is located between the pre-fractionation section distillation layer (7-3) and the pre-fractionation section stripping layer (7-4); the intermediate discharge section is provided with an intermediate discharge section distillation layer (7-11) and an intermediate discharge section stripping layer (7-12) which are provided at intervals up and down, and the MIBK outlet D is located between the intermediate discharge section distillation layer (7-11) and the intermediate discharge section stripping layer (7-12); the distillation section is provided with a distillation section distillation layer (7-5), and a gap is provided between the distillation section distillation layer (7-5) and the partition plate (8); the stripping section is provided with a stripping section stripping layer (7-8), and a gap is provided between the stripping section stripping layer (7-8) and the partition plate (8); The distillation tower (7) is provided with a raw material phase separator (1), a water phase extraction tank (2), an oil phase extraction tank (4), and a preheater (6) on the outside. The raw material phase separator (1) is provided with a middle inlet, an upper outlet, and a bottom outlet. The bottom outlet of the raw material phase separator (1) is connected to the water phase extraction tank (2), the upper outlet of the raw material phase separator (1) is connected to the upper inlet of the oil phase extraction tank (4), the inlet of the preheater (6) is connected to the bottom outlet of the oil phase extraction tank (4), and the outlet of the preheater (6) is connected to the MIBK extraction liquid feed port C of the distillation tower (7).

7. The distillation system for MIBK distillation according to claim 6, characterized in that: A MIBK produced liquid feed pipe (7-1) connected to a MIBK produced liquid feed port C is provided in the tower body, a first liquid distributor (7-2) is horizontally installed below the MIBK produced liquid feed pipe (7-1), and the MIBK produced liquid feed pipe (7-1) and the first liquid distributor (7-2) are both located between the pre-fractionation section rectification layer (7-3) and the pre-fractionation section stripping layer (7-4); a liquid discharge distributor (7-13) connected to a MIBK outlet D is provided in the tower body, and the liquid discharge distributor (7-13) is located between the intermediate discharge section rectification layer (7-11) and the intermediate discharge section stripping layer (7-12); an organic aqueous solution pipeline is connected to the bottom outlet of the water phase production tank (2), and an organic aqueous solution delivery pump (3) is provided on the organic aqueous solution pipeline; and a distillation tower feed pump (5) is provided on the pipeline between the oil phase production tank (4) and the preheater (6).

8. The distillation system for MIBK distillation according to claim 6, characterized in that: In the tower body, a horizontally arranged second liquid distributor (7-6) is installed between the rectifying layer (7-5) of the rectifying section and the partition plate (8); a gap is provided between the rectifying layer (7-5) of the rectifying section and the azeotrope outlet A; an oil phase reflux port B is provided on the side wall of the gap; a tube-type liquid distributor (7-7) is horizontally installed at the oil phase reflux port B; and the MIBK solution is refluxed sequentially through the azeotrope outlet A and the oil phase reflux port B.

9. The distillation system for MIBK distillation according to claim 6, characterized in that: A condenser (9) and a phase separation reflux device (10) are sequentially provided on the pipeline between the azeotrope outlet A and the oil phase reflux port B along the flow direction of the MIBK solution. The bottom of the phase separation reflux device (10) is connected to the water phase extraction tank (2) through a pipeline.

10. The distillation system for MIBK distillation according to claim 6, characterized in that: In the tower body, a third liquid distributor (7-9) is installed horizontally between the stripping layer (7-8) of the stripping section and the partition plate (8); a gap is provided between the stripping layer (7-8) of the stripping section and the tower bottom liquid outlet G, a steam reflux port E and a tower bottom liquid side wall outlet F are provided on the side wall of the gap, the steam reflux port E is located above the tower bottom liquid side wall outlet F, and an air inlet distributor (7-10) is installed horizontally at the steam reflux port E, the MIBK steam is refluxed in sequence through the tower bottom liquid side wall outlet F and the steam reflux port E, and a reboiler (11) is provided on the pipeline between the tower bottom liquid side wall outlet F and the steam reflux port E.

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