Rectification separation device and production system

Abstract

The utility model relates to the technical field of rectification separation, and discloses a rectification separation device and a production system, the rectification separation device comprises a rectification tower, a first auxiliary tower of the rectification tower and a second auxiliary tower of the rectification tower, the rectifying tower is provided with a feeding hole of the rectifying tower and a first side line extraction hole, and the position of the first side line extraction hole is not higher than that of the feeding hole of the rectifying tower; a reflux inlet, a second side line extraction opening and a feeding opening of the first auxiliary tower of the rectifying tower are formed in a tower body of the first auxiliary tower of the rectifying tower; the first side line extraction opening is communicated with a feeding opening of a first auxiliary tower of the rectifying tower; a tower top material outlet is formed in the tower top of the second auxiliary tower of the rectifying tower, a tower bottom material outlet is formed in the tower bottom, and a feeding hole of the second auxiliary tower of the rectifying tower is formed in the tower body; the feeding hole of the second auxiliary tower of the rectifying tower is communicated with the second side line extraction hole; and the tower bottom material outlet of the second auxiliary tower of the rectifying tower is communicated with the reflux inlet. The device can improve the separation efficiency of azeotropic products and by-products in the to-be-separated materials.

Description

Technical Field

[0001] The utility model relates to the technical field of distillation separation, in particular to a distillation separation device and a production system. Background Art

[0002] Vinyl acetate (VAc) is an important organic chemical raw material, widely used in the manufacture of polyvinyl acetate (PVA) and polyvinyl alcohol (PVA), and further processed into coatings, vinyl fibers, resins, and films. VAc can be produced via two routes: the acetylene process and the ethylene process. The ethylene process has become the predominant method for VAc production worldwide, employing catalysts supported by precious metals. However, the ethylene process, along with its core catalysts, has long been monopolized by foreign companies, and continues to present key and common technical challenges, such as low catalyst activity, short catalyst lifespan, and poor resistance to raw material interference.

[0003] At present, the method to increase vinyl acetate production is to renovate and expand the original equipment and replace the catalyst. The development trend of the ethylene route mainly has the following directions: (1) The scale of production equipment tends to be large-scale; (2) The ethylene process VAC process is improved in the direction of reducing unit consumption and energy consumption; (3) The distillation section of the existing vinyl acetate unit is extremely difficult to remove because vinyl acetate and ethyl acetate easily form azeotropes, and vinyl acetate with too high ethyl acetate content will affect the production of products such as EVA. Therefore, how to efficiently remove ethyl acetate from vinyl acetate has become an important research direction in vinyl acetate production. Utility Model Content

[0004] The purpose of the utility model is to overcome the problem in the prior art that by-products and main products in the product mixture are azeotropic and difficult to separate, and to provide a distillation separation device and a production system. The distillation separation device can effectively remove the azeotropic by-products and has a good separation effect.

[0005] In order to achieve the above-mentioned object, the present invention provides a distillation separation device, which comprises a distillation tower 1, a first distillation tower 2 and a second distillation tower 3;

[0006] The distillation tower 1 is provided with a feed inlet 101 and a first side line outlet 102 of the distillation tower. The first side line outlet 102 is located no higher than the feed inlet 101 of the distillation tower.

[0007] The tower body of the first sub-tower 2 of the distillation tower is provided with a reflux port 203, a second side-line outlet 202 and a feed port 201 of the first sub-tower of the distillation tower; the first side-line outlet 102 is connected to the feed port 201 of the first sub-tower of the distillation tower;

[0008] The second sub-tower 3 of the distillation tower is provided with a top material outlet at the top and a bottom material outlet at the bottom, and a feed inlet 301 of the second sub-tower of the distillation tower is provided on the tower body; the feed inlet 301 of the second sub-tower of the distillation tower is connected to the second side line production outlet 202, and the bottom material outlet of the second sub-tower 3 of the distillation tower is connected to the reflux port 203.

[0009] Optionally, the number of plates N1 of the distillation tower 1 is greater than the number of plates N2 of the first sub-tower 2 of the distillation tower, and the number of plates N2 of the first sub-tower 2 of the distillation tower is greater than the number of plates N3 of the second sub-tower 3 of the distillation tower.

[0010] Optionally, the first side line production outlet 102 is connected to the feed inlet 201 of the first sub-tower of the distillation tower through a first side production pipeline, and a first flow pump is provided on the first side production pipeline; and / or, the feed inlet 301 of the second sub-tower of the distillation tower is connected to the second side line production outlet 202 through a second side production pipeline, and a second flow pump is provided on the second side production pipeline.

[0011] Optionally, the number of plates N1 of the distillation tower is 60-100, and the position of the first side line outlet 102 is the a×N1th plate upward along the bottom of the distillation tower, where a is 0.2-0.4.

[0012] Optionally, the number of plates N2 of the first sub-tower 2 of the distillation tower is 10-70, and the position of the second side line outlet 202 is the b×N2th plate upward along the bottom of the tower, where b is 0.1-0.5.

[0013] Optionally, the position of the second side line outlet 202 is lower than the position of the feed inlet 201 of the first sub-tower of the distillation tower, and / or the position of the second side line outlet 202 and the feed inlet 201 of the first sub-tower of the distillation tower are staggered in the circumferential direction of the first sub-tower 2 of the distillation tower.

[0014] Optionally, the position of the reflux port 203 is lower than the position of the second side line production port 202; and / or, the reflux port 203 is connected to the bottom material outlet of the second sub-tower 3 of the distillation tower through a reflux pipeline, and a reflux pump is provided on the reflux pipeline to adjust the reflux rate.

[0015] Optionally, the number of plates N3 of the second sub-tower of the distillation tower is 5-20.

[0016] A second aspect of the present invention provides a production system, comprising a raw material supply unit, a reaction unit, and the distillation separation device according to the first aspect, which are connected in sequence;

[0017] The raw material supply unit is used to provide reaction raw materials to the reaction unit;

[0018] The reaction unit is provided with a raw material inlet connected to the raw material supply unit and a product outlet connected to the feed inlet 101 of the distillation tower, for reacting the reaction raw materials to obtain product streams, which are then fed into the distillation separation device.

[0019] Optionally, the bottom outlet of the distillation tower 1 is connected to the raw material inlet of the reaction unit and / or the raw material supply unit.

[0020] Optionally, the bottom outlet of the first sub-tower 2 of the rectification tower is connected to the raw material inlet of the reaction unit and / or the raw material supply unit.

[0021] The distillation separation device of the present invention adopts the above-mentioned technical scheme, which can improve the separation efficiency of products and by-products that exist in the material to be separated. The present invention can be applied to any reaction process involving gaseous raw materials, such as the ethylene-based vinyl acetate process, the acetylene-based vinyl acetate process, and other production processes where the products and by-products exist in the azeotropic state, resulting in great difficulty in separation, and can effectively improve the separation effect of the reaction products.

[0022] Other features and advantages of the present invention will be described in detail in the subsequent detailed description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a production system in one embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the production system used in Comparative Example 1.

[0025] Description of Reference Numerals

[0026] DETAILED DESCRIPTION

[0027] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0028] In this utility model, unless otherwise specified, directional words such as "upper, lower, left, right" generally refer to directions shown in the accompanying drawings. "Inside" and "outside" refer to inside and outside relative to the outline of each component itself.

[0029] On one hand, the present invention provides a distillation separation device, which comprises a distillation tower 1, a first distillation tower sub-tower 2 and a second distillation tower sub-tower 3;

[0030] The distillation tower 1 is provided with a feed inlet 101 and a first side line outlet 102 of the distillation tower. The first side line outlet 102 is located no higher than the feed inlet 101 of the distillation tower.

[0031] The tower body of the first sub-tower 2 of the distillation tower is provided with a reflux port 203, a second side-line outlet 202 and a feed port 201 of the first sub-tower of the distillation tower; the first side-line outlet 102 is connected to the feed port 201 of the first sub-tower of the distillation tower;

[0032] The second sub-tower 3 of the distillation tower is provided with a top material outlet at the top and a bottom material outlet at the bottom, and a feed inlet 301 of the second sub-tower of the distillation tower is provided on the tower body; the feed inlet 301 of the second sub-tower of the distillation tower is connected to the second side line production outlet 202, and the bottom material outlet of the second sub-tower 3 of the distillation tower is connected to the reflux port 203.

[0033] like Figure 1 As shown, when the above-mentioned distillation separation device is in use, the material to be separated enters the distillation separation device through the feed port 101 of the distillation tower. First, the first separation is performed in the distillation tower 1, and the target product is obtained from the top outlet of the tower. The high-boiling point by-products and unreacted raw materials are recovered at the bottom outlet of the tower. At the same time, a portion of the tower body material is extracted through the first side line extraction port 102 provided on the tower body of the distillation tower 1 and fed into the first sub-tower 2 of the distillation tower for second separation. By properly controlling the position of the first side line extraction port 102 on the tower body, at least a portion of the by-products that azeotropy with the target product can be extracted, reducing the azeotropy of the azeotropic by-products with the main product, thereby improving the product separation effect.

[0034] In conventional separation processes, some azeotropic products are difficult to separate and remain in the main product, affecting product quality. The distillation separation device provided by the utility model can improve the separation effect of azeotropic by-products, thereby increasing the purity of the product, and can adapt to various usage requirements. When used in a production system, it can effectively improve the separation effect of reaction products.

[0035] In the present invention, the distillation tower, the first sub-tower of the distillation tower and the second sub-tower of the distillation tower can have any conventional device structure and composition in the art, and are preferably gas-liquid separation towers.

[0036] According to a preferred embodiment of the present invention, the number of plates N1 of the distillation tower 1 is greater than the number of plates N2 of the first distillation tower sub-tower 2, and the number of plates N2 of the first distillation tower sub-tower 2 is greater than the number of plates N3 of the second distillation tower sub-tower 3.

[0037] It can be understood that, in the present invention, the flow rate and proportion of the side-line extracted material of the distillation tower or the first sub-tower of the distillation tower can be controlled by a flow pump.

[0038] According to a preferred embodiment of the present invention, the first side line production port 102 is connected to the feed port 201 of the first sub-tower of the distillation tower through a first side production pipeline, and a first flow pump is provided on the first side production pipeline.

[0039] According to a preferred embodiment of the present invention, the feed inlet 301 of the second sub-tower of the distillation tower is connected to the second side line outlet 202 through a second side sampling pipeline, and a second flow pump is provided on the second side sampling pipeline.

[0040] According to a preferred embodiment of the present invention, the number of plates N1 of the distillation tower is 60-100, preferably 60-80.

[0041] To further improve separation efficiency, the first side-line outlet 102 is located at the a×N1th tray upward from the bottom of the distillation column, where a is 0.2-0.4, preferably 0.2-0.3. When a×N1 is not an integer, the result is rounded down. For example, when the distillation column has 80 trays, the side-line outlet can be located anywhere from the 16th tray to the 32nd tray upward from the bottom of the column.

[0042] Preferably, the position of the first side line extraction port 102 and the feed port 101 of the distillation tower are offset from each other in the circumferential direction of the distillation tower. Further preferably, the position of the first side line extraction port 102 and the feed port 101 of the distillation tower are arranged in opposite directions in the circumferential direction of the distillation tower.

[0043] According to a preferred embodiment of the present invention, the number of plates N2 of the first sub-tower 2 of the distillation tower is 10-70, preferably 30-60.

[0044] According to a preferred embodiment of the present invention, the second side line outlet 202 is located at the b×N2th tray upward from the bottom of the tower, where b is 0.1-0.5, more preferably 0.2-0.4. When b×N2 is not an integer, the result is rounded down.

[0045] According to a preferred embodiment of the present invention, the position of the second side line outlet 202 is lower than the position of the feed inlet 201 of the first sub-tower of the distillation tower.

[0046] In addition, the position of the second side-line withdrawal port 202 is lower than the position of the feed inlet 201 of the first sub-tower of the distillation column, or the position of the second side-line withdrawal port 202 and the position of the feed inlet 201 of the first sub-tower of the distillation column may be offset relative to each other in the circumferential direction of the first sub-tower of the distillation column. Preferably, the position of the second side-line withdrawal port 202 is lower than the position of the feed inlet 201 of the first sub-tower of the distillation column, and the position of the second side-line withdrawal port 202 and the position of the feed inlet 201 of the first sub-tower of the distillation column are offset relative to each other in the circumferential direction of the first sub-tower of the distillation column.

[0047] Among them, as preferred, Figure 1 As shown, the position of the second side line outlet 202 is lower than the position of the feed inlet 201 of the first sub-tower, and the feed inlet 201 of the first sub-tower of the distillation tower and the position of the second side line outlet 202 are arranged back to back in the circumferential direction of the first sub-tower of the distillation tower.

[0048] According to a preferred embodiment of the present invention, the position of the reflux port 203 is lower than the position of the second side-line production port 202 .

[0049] According to a preferred embodiment of the present invention, the reflux port 203 is connected to the bottom material outlet of the second distillation tower 3 via a reflux line. A reflux pump is provided on the reflux line to adjust the reflux rate. It is understood that the entire bottom material of the second distillation tower is refluxed back to the first distillation tower via the reflux line. This preferred embodiment facilitates further removal of by-products and, when used in a production system, helps reduce overall production energy consumption.

[0050] According to a preferred embodiment of the present invention, the number of plates N3 of the second sub-tower of the distillation tower is 5-20, preferably 5-15.

[0051] A second aspect of the present invention provides a production system, comprising a raw material supply unit, a reaction unit, and the distillation separation device according to the first aspect, which are connected in sequence;

[0052] The raw material supply unit is used to provide reaction raw materials to the reaction unit;

[0053] The reaction unit is provided with a raw material inlet connected to the raw material supply unit and a product outlet connected to the feed inlet 101 of the distillation tower, for reacting the reaction raw materials to obtain product streams, which are then fed into the distillation separation device.

[0054] In the present invention, the raw material supply unit may include one or more raw material storage tanks, and the reaction raw materials may be fed into the reaction unit separately or mixed together. Those skilled in the art may select the appropriate method according to the needs of different reactions.

[0055] The reaction unit may include one or more reactors, and the reactor may be any conventional device or composition in the art, for example, may include one or more parallel reaction towers.

[0056] The utility model can be applied to any reaction process involving gaseous raw materials, such as ethylene-based vinyl acetate process, acetylene-based vinyl acetate process and other production processes where the product and by-products have azeotropic properties, resulting in great difficulty in separation.

[0057] According to a preferred embodiment of the present invention, the bottom outlet of the distillation tower 1 is connected to the raw material inlet and / or the raw material supply unit of the reaction unit, and / or the bottom outlet of the first sub-tower 2 of the distillation tower is connected to the raw material inlet and / or the raw material supply unit of the reaction unit. By adopting the above preferred embodiment, the unreacted raw materials obtained from the bottom outlet of the distillation tower 1 and / or the bottom outlet of the first sub-tower 2 of the distillation tower can be recovered. Among them, an optional raw material purification device can also be included between the bottom outlet of the distillation tower 1 and the raw material inlet and / or the raw material supply unit of the reaction unit, which is used to purify the recovered raw materials and then put them into the reaction system. The present invention has no special limitation on this, and those skilled in the art can make a choice according to the needs of the specific reaction raw materials.

[0058] The following describes the embodiments of the present invention in detail through examples.

[0059] Example 1

[0060] Use Figure 1 The production system shown is for vinyl acetate production.

[0061] The production system includes: a raw material supply unit, a reaction unit, and a crude product distillation unit connected in sequence along the logistics direction; wherein the reaction unit includes a reactor, and the crude product distillation unit includes a distillation tower 1, a first sub-tower 2 of the distillation tower, and a second sub-tower 3 of the distillation tower. The distillation tower 1 has 70 plates, and the first side intake of the distillation tower 1 is located at the 15th tray upward from the bottom of the tower; the first sub-tower 2 of the distillation tower has 40 plates, the second side intake of the first sub-tower 2 of the distillation tower is located at the 10th tray upward from the bottom of the tower, and the reflux port is located at the 7th tray upward from the bottom of the tower; the second sub-tower 3 of the distillation tower has 10 plates.

[0062] The production process of vinyl acetate includes:

[0063] (1) The reactor was filled with 14,000 kg of Sinopec commercial CTV-IV vinyl acetate catalyst, the temperature was 150 °C, the pressure was 0.8 MPa, the raw materials were fed in a molar ratio of acetic acid to ethylene of 0.2:1, and the total volumetric space velocity of ethylene and acetic acid was 1950 h -1After the reaction, a crude product stream containing vinyl acetate (34 wt%), acetic acid, water, ethyl acetate (500 ppmw), acetaldehyde, etc. was obtained at a temperature of 108°C.

[0064] (2) The crude product stream is fed into a distillation tower at a rate of 40 t / h for separation to obtain a heavy component (acetic acid 97% wt) and a light component. The bottom temperature of the distillation tower is 120°C and the top temperature is 65°C.

[0065] (3) A stream containing ethyl acetate (wherein the ethyl acetate content is 1.5 wt%) is extracted through the first side-line outlet of the distillation tower 1 (15 trays upward from the bottom of the tower) and fed into the first sub-tower of the distillation tower. The temperature of the extracted material is 115°C and the flow rate is 0.6 t / h. The top temperature of the first sub-tower of the distillation tower is 65°C and the bottom temperature is 122°C. The side-line stream undergoes a second separation in the first sub-tower of the distillation tower to obtain light components and heavy components. The light components are fed to a low-boiling treatment unit. The heavy components obtained from the distillation tower and the first sub-tower of the distillation tower are mixed and fed to an acetic acid evaporator to recover the acetic acid to provide the acetic acid in step (1).

[0066] (4) The extracted stream is sent to the second sub-tower 3 of the distillation tower through the second side-line outlet of the first sub-tower 2 of the distillation tower, wherein the temperature of the extracted stream is 105°C and the flow rate is 50 kg / h; the top temperature of the second sub-tower of the distillation tower is 95°C and the bottom temperature is 115°C; the side-extracted stream undergoes a third separation in the second sub-tower of the distillation tower to obtain light components and heavy components, the light components are sent to low-boiling treatment, and the heavy components are returned to the first sub-tower of the distillation tower through the reflux port.

[0067] After 100 h of continuous reaction, samples were taken from the inlet of distillation tower 1 to calculate the yield and selectivity of vinyl acetate and the energy consumption of the system. The results are shown in Table 1. Samples were taken from the top outlet of distillation tower 1, and the ethyl acetate content in the product was analyzed by chromatography.

[0068] Selectivity of vinyl acetate (%) = vinyl acetate production per unit time (kg) * 28 / 86 / ethylene consumption per unit time (kg) × 100%;

[0069] Acetic acid unit consumption (kg / tVac) = acetic acid consumption per unit time of the device (kg) / vinyl acetate production per unit time of the device (t).

[0070] Example 2

[0071] The method of Example 1 is followed, except that the first side sampling port of the distillation tower 1 is arranged at the 26th tower plate upward along the tower bottom; the second side sampling port of the first sub-tower 2 of the distillation tower is arranged at the 4th tower plate upward along the tower bottom, and the reflux port is arranged at the 3rd tower plate upward along the tower bottom.

[0072] After 100 hours of continuous reaction, samples were taken from the feed port of distillation tower 1 to calculate the yield and selectivity of vinyl acetate and the energy consumption of the system. Samples were taken from the top outlet of distillation tower 1 and the content of ethyl acetate in the product was analyzed by chromatography. The results are shown in Table 1.

[0073] Comparative Example 1

[0074] Use Figure 2 The production system shown is used to produce vinyl acetate. Compared with Example 1, the production system does not contain the first sub-tower of the distillation tower and the second sub-tower of the distillation tower.

[0075] The production process of vinyl acetate includes:

[0076] (1) The reactor was filled with 14,000 kg of Sinopec commercial CTV-IV vinyl acetate catalyst, the temperature was 150 °C, the pressure was 0.8 MPa, the raw materials were fed in a molar ratio of acetic acid to ethylene of 0.2:1, and the total volumetric space velocity of ethylene and acetic acid was 1950 h -1 After the reaction, a crude product stream containing vinyl acetate (32 wt%), acetic acid, water, ethyl acetate (500 ppmw), acetaldehyde, etc. was obtained at a temperature of 108°C.

[0077] (2) The crude product stream is fed into the first distillation tower at a rate of 40 t / h for separation to obtain heavy components (acetic acid 97% wt) and light components. The bottom temperature of the distillation tower is 120°C and the top temperature is 65°C.

[0078] After 100 hours of continuous reaction, samples were taken from the feed port of distillation tower 1 to calculate the yield and selectivity of vinyl acetate and the energy consumption of the system. Samples were taken from the top outlet of distillation tower 1 and the content of ethyl acetate in the product was analyzed by chromatography. The results are shown in Table 1.

[0079] Table 1

[0080]

[0081] From the comparison of the above embodiments and comparative examples, it can be seen that the distillation separation device provided by the present invention can effectively reduce the azeotropic formation of ethyl acetate and vinyl acetate during the distillation process, and the content of ethyl acetate in the obtained VAC is greatly reduced, and the product quality is high.

[0082] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0083] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0084] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A distillation separation device, characterized in that: The distillation separation device comprises a distillation tower (1), a first distillation tower sub-tower (2) and a second distillation tower sub-tower (3); The distillation tower (1) is provided with a feed inlet (101) of the distillation tower and a first side line outlet (102) on the tower body, and the position of the first side line outlet (102) is not higher than the position of the feed inlet (101) of the distillation tower; The tower body of the first sub-tower (2) of the distillation tower is provided with a reflux port (203), a second side-line extraction port (202), and a feed port (201) of the first sub-tower of the distillation tower; the first side-line extraction port (102) is in communication with the feed port (201) of the first sub-tower of the distillation tower; The second sub-tower (3) of the distillation tower is provided with a top material outlet at the top, a bottom material outlet at the bottom, and a feed inlet (301) of the second sub-tower of the distillation tower is provided on the tower body; the feed inlet (301) of the second sub-tower of the distillation tower is connected to the second side line production outlet (202), and the bottom material outlet of the second sub-tower (3) of the distillation tower is connected to the reflux port (203).

2. The distillation separation device according to claim 1, characterized in that The number of plates N1 of the distillation tower (1) is greater than the number of plates N2 of the first sub-tower (2) of the distillation tower, and the number of plates N2 of the first sub-tower (2) of the distillation tower is greater than the number of plates N3 of the second sub-tower (3) of the distillation tower.

3. The distillation separation device according to claim 1 or 2, characterized in that: The first side line extraction port (102) is connected to the feed port (201) of the first sub-tower of the distillation tower via a first side extraction pipeline, and a first flow pump is provided on the first side extraction pipeline; Preferably, the feed inlet (301) of the second sub-tower of the distillation tower is connected to the second side line production outlet (202) through a second side production pipeline, and a second flow pump is provided on the second side production pipeline.

4. The distillation separation device according to claim 1 or 2, characterized in that: The number of plates N1 of the distillation tower is 60-100; The first side line outlet (102) is located at the a×N1th tray upward along the bottom of the distillation tower, where a is 0.2-0.

4.

5. The distillation separation device according to claim 1 or 2, characterized in that: The number of plates N2 of the first sub-tower (2) of the distillation tower is 10-70; The second side line outlet (202) is located at the b×N2th tray upward along the bottom of the tower, where b is 0.1-0.

5.

6. The distillation separation device according to claim 1, characterized in that: The position of the second side-line extraction port (202) is lower than the position of the feed port (201) of the first sub-tower of the distillation tower, and / or the position of the second side-line extraction port (202) and the feed port (201) of the first sub-tower of the distillation tower are offset from each other in the circumferential direction of the first sub-tower (2) of the distillation tower.

7. The distillation separation device according to claim 1, characterized in that: The position of the reflux port (203) is lower than the position of the second side-line production port (202); The reflux port (203) is connected to the bottom material outlet of the second sub-tower (3) of the distillation tower through a reflux pipeline, and a reflux pump is provided on the reflux pipeline to adjust the reflux rate.

8. The distillation separation device according to claim 1, characterized in that: The number of plates N3 of the second sub-tower of the distillation tower is 5-20.

9. A production system, characterized in that: The production system comprises a raw material supply unit, a reaction unit and a distillation separation device according to any one of claims 1 to 8, which are connected in sequence; The raw material supply unit is used to provide reaction raw materials to the reaction unit; The reaction unit is provided with a raw material inlet connected to the raw material supply unit, and a product outlet connected to the feed inlet (101) of the distillation tower, for reacting the reaction raw materials to obtain product flow, which is then sent to the distillation separation device.

10. The production system according to claim 9, characterized in that The bottom outlet of the distillation tower (1) is connected to the raw material inlet of the reaction unit and / or the raw material supply unit; And / or, the bottom outlet of the first sub-tower (2) of the distillation tower is connected to the raw material inlet of the reaction unit and / or the raw material supply unit.

Images