阅读说明：本技术 用于共沸混合溶液分离的精馏设备及方法 (Rectification equipment and method for separating azeotropic mixed solution ) 是由 李明一 薄德臣 高明 王璐瑶 于 2020-06-11 设计创作，主要内容包括：本发明公开了一种用于共沸混合溶液分离的精馏设备,包括：塔盘,其数量为多个且分层设置在精馏复合塔中；毛细精馏管束,其贯穿设置于多层塔盘中,该毛细精馏管束顶部连接至精馏复合塔的塔顶冷凝器,该毛细精馏管束底部连接至精馏复合塔的塔底再沸器。本发明还公开了一种精馏方法,使得极性弱的轻组分在毛细精馏管束内气化上升,极性强的重组分在毛细力的作用下留在液相中,进而改变共沸混合溶液中共沸物的气液平衡。本发明的设备和方法无需加入第三方溶剂即可实现共沸体系分离,突破共沸溶液体下的共沸点,同时对原料的适用面较广,分离能耗更低。(The invention discloses a rectifying device for separating azeotropic mixed solution, which comprises: a plurality of tower trays which are arranged in the rectifying composite tower in a layered mode; and the capillary rectifying tube bundle penetrates through the multilayer tower tray, the top of the capillary rectifying tube bundle is connected to a tower top condenser of the rectifying composite tower, and the bottom of the capillary rectifying tube bundle is connected to a tower bottom reboiler of the rectifying composite tower. The invention also discloses a rectification method, which ensures that the light component with weak polarity is gasified and ascended in the capillary rectification tube bundle, and the heavy component with strong polarity is remained in the liquid phase under the action of capillary force, thereby changing the gas-liquid balance of the azeotrope in the azeotropic mixed solution. The device and the method can realize the separation of an azeotropic system without adding a third-party solvent, break through the azeotropic point under the azeotropic solution, have wider application range to raw materials and lower energy consumption for separation.)

1. A rectification apparatus for separation of an azeotropic mixture solution, comprising:

a plurality of tower trays which are arranged in the rectifying composite tower in a layered mode;

and the capillary rectifying tube bundle penetrates through the plurality of layers of tower trays, the top of the capillary rectifying tube bundle is connected to a tower top condenser of the rectifying composite tower, and the bottom of the capillary rectifying tube bundle is connected to a tower bottom reboiler of the rectifying composite tower.

2. The rectification apparatus for azeotropic mixture solution separation as claimed in claim 1, wherein the capillary rectification tube bundle is composed of a plurality of capillary metal tubes, and the capillary metal tubes are uniformly distributed in the rectification composite tower body and extend along the axis of the rectification composite tower body.

3. The rectification apparatus for azeotropic mixture solution separation according to claim 2, wherein the plurality of capillary metal tubes are distributed radially and annularly from the center of the rectification composite tower and are arranged perpendicular to the tray.

4. A rectification apparatus for azeotropic mixture solution separation according to any one of claims 1 to 3, wherein the capillary rectification tube bundle is closed relative to the tray, and the feed inlet of the capillary rectification tube bundle is located in the middle of the rectification composite column.

5. The rectification apparatus for azeotropic mixture solution separation according to claim 4, wherein the feed inlet is in communication with each capillary metal tube of the capillary rectification tube bundle.

6. The rectification apparatus for azeotropic mixture solution separation according to claim 2, wherein the capillary metal pipe is a hollow stainless steel pipe.

7. The rectification apparatus for separation of an azeotropic mixture solution according to claim 6, wherein the stainless steel pipe is filled with a wave-shaped, thorn-shaped or convex-shaped bubble breaking piece.

8. The rectification apparatus for azeotropic mixture solution separation according to claim 4, wherein the incoming material at the feed inlet is the azeotropic mixture solution heated to the bubble point.

9. The rectification apparatus for separating the azeotropic mixture solution according to claim 1, wherein the temperature of the tower top condenser is reduced by air cooling or water cooling.

10. The rectification apparatus for azeotropic mixture solution separation as claimed in claim 1, wherein the bottom reboiler uses low pressure steam, medium pressure steam or heat conducting oil for heat exchange.

11. The rectification apparatus for azeotropic mixture solution separation of claim 1, wherein the tray is a sieve tray, a bubble cap tray or a packing tray.

12. A rectification method for separating an azeotropic mixed solution is characterized by comprising the following steps of:

conveying the azeotropic mixed solution into a capillary distillation tube bundle from a feed inlet;

the light component with weak polarity is gasified and ascended in the capillary rectifying tube bundle, and the heavy component with strong polarity is remained in the liquid phase under the action of capillary force, so that the gas-liquid balance of an azeotrope in the azeotropic mixed solution is changed;

the gasified and risen light components enter the tray from top to bottom after being condensed at the tower top of the rectification composite tower, the heavy components remained in the liquid phase enter the tray from bottom to top after being reboiled at the tower bottom, and the gas-liquid two phases carry out heat and mass transfer on the tray so as to finish the rectification process.

13. A rectification process for the separation of an azeotropic mixture solution according to claim 12, wherein the feed of the azeotropic mixture solution is delivered to the middle of the capillary tube bundle.

14. A rectification method for azeotropic mixture solution separation as claimed in claim 12, wherein the bubbles of the light component with weak polarity are broken during the gasification and rising in the capillary rectification tube bundle, so as to prevent the capillary rectification tube bundle from being blocked by the rising bubbles too much.

15. A rectification method for azeotropic mixture solution separation as claimed in claim 12, wherein said capillary tube bundle penetrates said trays of each layer, the rectifying section of said trays is embedded in the stripping section, and heat transfer is performed through the outer wall of said capillary tube bundle.

16. A rectification method for azeotropic mixture solution separation as claimed in claim 12, wherein the pressure in the rectification composite column during rectification is 0.1MPa to 10 MPa; the temperature in the rectification composite tower is 20-600 ℃.

Technical Field

The invention relates to the technical field of mixture separation of chemical products, in particular to a rectification device and a rectification method for separating an azeotropic mixed solution.

Background

The rectification process is the typical operation for separating liquid mixtures and is the separation operation most widely used in the process industry. In the conventional rectification operation, the mixture forms a gas-liquid two-phase system by utilizing the relative volatility difference of each component in the liquid mixture through a heat transfer method, and the components are contacted with each other to transfer heat and mass, so that the separation of the mixture is realized. Thus, the greater the difference in relative volatility between the components, the easier the system can be separated.

The traditional rectification operation is usually carried out in a rectification tower, and gas and liquid are in countercurrent contact to carry out interphase heat and mass transfer. The volatile component in the liquid phase enters the gas phase, and the non-volatile component in the gas phase is transferred into the liquid phase, so that the nearly pure volatile component can be obtained at the top of the tower, and the nearly pure non-volatile component can be obtained at the bottom of the tower. The feed liquid is added from the middle part of the tower, and the tower section above the feed inlet further thickens volatile components in the rising steam, which is called as a rectifying section; the section of the column below the feed opening, which extracts the volatile components from the descending liquid, is referred to as the stripping section. Condensing the vapor led out from the tower top, returning a part of condensate as reflux liquid from the tower top to the rectifying tower, and obtaining the rest distillate as a tower top product. The liquid extracted from the tower bottom is partially gasified by a reboiler, the vapor rises along the tower, and the rest liquid is used as a tower bottom product.

However, after part of solution components are mixed according to a specific proportion, because the saturated vapor pressure of the solution components deviates from Raoult's law, an azeotrope is easily formed, namely the relative volatility is close to 1, and after the solution components are heated to boil, the proportion of two substances in a gas phase is consistent with that of two substances in a liquid phase. The energy consumption for separating the azeotrope by adopting the traditional rectification operation is very large, and the methods of azeotropic rectification and extractive rectification are generally adopted in the industry at present, namely, a third component is added into the azeotrope solution, so that the relative volatility of the components to be separated is improved.

The traditional azeotropic distillation and extractive distillation need to add a third-party solvent, so the requirement on the third-party solvent is higher, the use system is more limited, the azeotropic distillation requires that the newly formed azeotropic liquid has a low boiling point, is a heterogeneous mixture and is convenient to separate by a layering method, and the extractive distillation requires that the extractant can obviously change the relative volatility among the original components, and the boiling point is far higher than that of each component of the original solution.

For example, chinese patent application CN109851499A discloses a method and an apparatus for separating benzene from vinyl acetate by azeotropic distillation. Any one or a mixture of more of methanol, water, ethanol, propanol and butanol is used as an entrainer, and benzene in vinyl acetate is separated through azeotropic rectification; the benzene content in the vinyl acetate is reduced to below 1 ppm. The separation system has simple structure, the separation towers are normal pressure towers, the operation cost is low, and the separation system is safe and environment-friendly. The method can effectively remove benzene which is an impurity from trace to constant level.

The prior art also comprises a separation method without using an entrainer, for example, Chinese patent application CN107970632A discloses an azeotropic distillation separation device, which is provided with a condensation phase separation unit comprising a condensation pipe and a phase separation part, and realizes the separation of a binary azeotropic mixture without adding the entrainer, namely the binary azeotropic mixture formed by n-hexanol and water can be separated, the pertinence is strong, and the recovered n-hexanol can be reused as a raw material. However, this method requires the mixed solution to be a heterogeneous mixture at a condensing temperature, and has a large limitation on the raw materials and a poor separation effect.

For another example, chinese patent application CN103007564A discloses a method for rectifying a solution by capillary force, which accelerates capillary condensation and separation of the solution by the surface tension phenomenon of the capillary in the water phase, but the apparatus only uses capillary force as a driving force to accelerate condensation and separation of the gas phase in the overhead condenser, and has no effect on improving the quality of products at the top and bottom of the tower.

The existing azeotropic separation method usually needs to add a third-party solvent, so that the separation system is limited, and the traditional rectification method can not change the relative volatility of the solution of the azeotropic system, so that the azeotropic separation efficiency is low. Therefore, a rectification apparatus and a rectification method which can realize the separation of an azeotropic system without using a third-party solvent, have wide application range to raw materials and low energy consumption for separation are needed, so that the problems in the prior art are effectively solved.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

The invention aims to provide a rectification device, which utilizes the characteristic that a capillary metal pipe fitting has different acting forces on different polar components in an azeotropic system solution, changes the gas-liquid balance of an azeotrope, breaks through the azeotropic point under the azeotropic solution, can realize the separation of the azeotropic system without adding a third-party solvent, and has wider application range on raw materials and lower separation energy consumption.

Another object of the present invention is to provide a method for separating an azeotropic mixture solution by using the aforementioned rectifying apparatus.

To achieve the above object, according to a first aspect of the present invention, there is provided a rectification apparatus for azeotropic mixture solution separation, comprising: a plurality of tower trays which are arranged in the rectifying composite tower in a layered mode; and the capillary rectifying tube bundle penetrates through the multilayer tower tray, the top of the capillary rectifying tube bundle is connected to a tower top condenser of the rectifying composite tower, and the bottom of the capillary rectifying tube bundle is connected to a tower bottom reboiler of the rectifying composite tower.

Further, among the above-mentioned technical scheme, capillary rectification tube bank can comprise many capillary metal pipe fittings, and many capillary metal pipe fittings can evenly be arranged in the tower body of rectification composite tower and extend along the tower body axis.

Further, in the above technical scheme, a plurality of capillary metal pipe fittings can be distributed in a radial ring shape from the center of the rectification composite tower and are all arranged perpendicular to the tower tray.

Further, in the above technical scheme, the capillary rectification tube bundle is in a closed state relative to the tray, and the feed inlet of the capillary rectification tube bundle is positioned in the middle of the rectification composite tower. The feed inlet is communicated with each capillary metal pipe fitting of the capillary rectifying pipe bundle.

Further, in the above technical scheme, the capillary metal pipe fitting may be a hollow stainless steel pipe fitting.

Furthermore, in the technical scheme, the stainless steel pipe fitting can be filled with wavy, thorn-shaped or convex bubble-breaking sheets.

Further, in the above technical scheme, the incoming material at the feed inlet is an azeotropic mixed solution heated to the bubble point.

Further, in the above technical scheme, the tower top condenser can be cooled by air cooling or water cooling. The reboiler at the bottom of the tower can adopt low-pressure steam, medium-pressure steam or heat transfer oil and the like for heat exchange.

Further, in the above technical solution, the tray may be a sieve tray, a bubble cap tray, or a packing tray.

In order to achieve another object described above, according to a second aspect of the present invention, there is provided a rectification method for separation of an azeotropic mixture solution, comprising the steps of: conveying the azeotropic mixed solution into a capillary distillation tube bundle from a feed inlet; the light component with weak polarity is gasified and ascended in the capillary rectifying tube bundle, and the heavy component with strong polarity is remained in the liquid phase under the action of capillary force, so that the gas-liquid balance of the azeotrope in the azeotropic mixed solution is changed; the gasified and ascending light components enter the tray from top to bottom after being condensed at the tower top of the rectification composite tower, the heavy components remained in the liquid phase enter the tray from bottom to top after being reboiled at the tower bottom, and the gas-liquid two phases carry out heat and mass transfer on the tray so as to finish the rectification process.

Further, in the above technical scheme, the feeding of the azeotropic mixed solution is conveyed to the middle part of the capillary distillation tube bundle.

Further, in the technical scheme, the bubble breaking step can be carried out on the light component with weak polarity in the gasification and rising process in the capillary rectification tube bundle, so that the capillary rectification tube bundle is prevented from being blocked by the rising bubbles too much.

Further, in the above technical scheme, the capillary distillation tube bundle penetrates through the trays of each layer, the distillation section of the tray is embedded in the stripping section, and heat is transferred through the outer wall of the capillary distillation tube bundle.

Compared with the prior art, the invention has the following beneficial effects:

the equipment and the method for rectifying the azeotropic mixed solution can couple capillary rectification with conventional rectification, carry out preliminary separation by utilizing the difference of capillary force between light and heavy components to obtain tower top discharge and tower bottom discharge which deviate from the composition of the azeotropic solution, and recycle the tower top discharge and the tower bottom discharge to a conventional tower tray for separation to obtain light and heavy components with high purity; in addition, the equipment and the method fully utilize the heat conduction property of the capillary tube bundle, couple the capillary rectification area with the stripping section and the rectification section of the conventional rectification area, optimize the structure of the rectification tower from the traditional upper section as the rectification section and the traditional lower section as the stripping section as the rectification section, and embed the rectification section in the stripping section, and transfer heat through the outer wall of the capillary rectification tube bundle, so that the heat transfer between gas and liquid to be separated is realized, and the integral heat utilization efficiency of the equipment can be effectively improved.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood and to make the technical means implementable in accordance with the contents of the description, and to make the above and other objects, technical features, and advantages of the present invention more comprehensible, one or more preferred embodiments are described below in detail with reference to the accompanying drawings.

Drawings

FIG. 1 is a schematic view of a rectification apparatus for azeotropic mixture solution separation according to the present invention.

FIG. 2 is a schematic cross-sectional view of a rectifying complex column in a rectifying apparatus according to the present invention.

FIG. 3 is a schematic view of the structure of a capillary rectifying tube in the rectifying apparatus of the present invention.

FIG. 4 is a schematic diagram of the rectifying section of the rectifying composite column in the rectifying apparatus of the present invention (showing the capillary rectifying section and the intermediate products produced by the section).

FIG. 5 is a schematic drawing of the stripping section of the rectifying complex column in the rectifying apparatus of the present invention (showing the various layers of trays and the final product produced by the section).

Description of the main reference numerals:

1-a rectifying composite tower, 2-a capillary rectifying tube bundle, 21-a bubble breaking sheet, 3-a stripping section tower tray, 4-a tower top condenser, 5-a tower top reflux pump, 6-a tower bottom circulating pump and 7-a tower bottom reboiler;

a-azeotropic mixture solution, B-final product at the top of the column, C-final product at the bottom of the column, B '-intermediate product at the top of the column, and C' -intermediate product at the bottom of the column.

Detailed Description

The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.

Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.

Spatially relative terms, such as "below," "lower," "upper," "above," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the object in use or operation in addition to the orientation depicted in the figures. For example, if the items in the figures are turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the elements or features. Thus, the exemplary term "below" can encompass both an orientation of below and above. The article may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.

In this document, the terms "first", "second", etc. are used to distinguish two different elements or portions, and are not used to define a particular position or relative relationship. In other words, the terms "first," "second," and the like may also be interchanged with one another in some embodiments.

As shown in fig. 1, the present invention provides a rectification apparatus and a rectification method for separating an azeotropic mixture solution a by means of capillary adsorption, wherein the rectification apparatus is a rectification composite tower 1, and comprises a plurality of trays (namely, stripping section trays 3 of the present invention) and a capillary rectification tube bundle 2, and the trays are arranged in the rectification composite tower 1 in a layered manner. The capillary rectifying tube bundle 2 is arranged in the multilayer tower tray in a penetrating mode, the top of the capillary rectifying tube bundle 2 is connected to a tower top condenser 4 of the rectifying composite tower, and the bottom of the capillary rectifying tube bundle 2 is connected to a tower bottom reboiler 7 of the rectifying composite tower 1. Specifically, the rectifying composite tower 1 sequentially comprises a tower top condensing area, a tower body and a tower bottom reboiling area from top to bottom, a capillary rectifying tube bundle 2 and a stripping section tower tray 3 are arranged in the tower body, the capillary rectifying tube bundle 2 is uniformly distributed in the tower body, and the tower tray 3 is circularly distributed around the capillary rectifying tube bundle from top to bottom. The top discharge of the capillary rectification area is connected to a top condenser 4, and the condensed material at the top is connected to the tower body as the liquid phase feed of the stripping section tray 3. The tower bottom discharge of the capillary rectification area is connected to a reboiler 7, and the gas phase discharge after reboiling is totally returned to the tower body to be used as the gas phase feed of the stripping section tower tray 3.

As further shown in fig. 1 and 2, the capillary rectifying tube bundle 2 is composed of a plurality of capillary metal tube members, and the capillary metal tube members are uniformly distributed in the tower body of the rectifying composite tower 1 and extend along the axis of the tower body. As shown in fig. 2, a plurality of capillary metal pipes are distributed radially and annularly from the center of the rectification composite tower and are all arranged perpendicular to each layer of tray 3. Preferably, but not limitatively, the capillary metal tubing is hollow stainless steel tubing. The capillary rectifying tube bundle 2 is in a closed state relative to the tray, and the outer wall of the capillary rectifying tube bundle 2 and the gas-liquid phase substance in the tray 3 only have a heat transfer process (namely, no mass transfer occurs in the capillary metal pipe fitting). The feed inlet of the capillary rectifying tube bundle 2 is positioned in the middle of the rectifying composite tower 1. In order to evenly convey the materials into the capillary metal pipe fittings, the feed inlet is communicated with each capillary metal pipe fitting of the capillary rectifying tube bundle 2.

As further shown in fig. 3, preferably, but not by way of limitation, the stainless steel tubing is filled with bubble-breaking sheets 21 to prevent excessive pressure drop in the capillary rectification tube bundle 2 due to excessive blockage of the tubing by rising bubbles. The bubble-breaking sheet 21 may be a wave-shaped, thorn-shaped or convex-shaped one, as long as it can effectively puncture the rising large bubbles.

Furthermore, the incoming material at the feed inlet of the capillary distillation tube bundle 2 is an azeotropic mixed solution heated to the bubble point. The tower top condenser 4 can adopt an air cooling or water cooling mode for cooling. The reboiler 7 at the bottom of the tower can adopt low-pressure steam, medium-pressure steam or heat conducting oil for heat exchange. Tray 3 may be a sieve tray, a bubble cap tray or a packing tray.

In the area, an azeotropic mixed solution A enters the capillary distillation tube bundle 2 and then realizes initial product separation under the combined action of capillary force and gravity, namely, under the action of capillary force, a light component with weaker polarity in the azeotropic mixed solution A has weaker adsorption force on the tube wall and is easy to gasify and rise, and a heavy component with stronger polarity in the azeotropic mixed solution A has stronger adsorption force on the tube wall and descends along with a liquid phase in the tube, so that the composition of a solution of an azeotropic system is broken in the area. The area of the capillary rectifying tube bundle 2 is a rectifying area (refer to figure 4) of the invention, and a plurality of layers of trays 3 distributed from top to bottom in the rectifying composite tower 1 form a stripping area (refer to figure 5), in the area, gas and liquid phases formed by azeotropic points are broken through in the rectifying area of the invention to carry out mass transfer and heat transfer, thus further improving the concentration effect of the solution.

As further shown in fig. 1, 4 and 5, the rectification method for separating the azeotropic mixture solution of the present invention employs the rectification apparatus of the present invention, that is, the capillary rectification tube bundle 2 penetrates the trays 3 of each layer of the rectification composite tower 1, and the rectification sections of the trays are embedded in the stripping section. The method comprises the following steps: firstly, conveying an azeotropic mixed solution A into a capillary distillation tube bundle 2 from a feed inlet; then, after the azeotropic mixed solution A enters the capillary distillation tube bundle 2, the light component with weaker polarity is gasified and ascended in the capillary distillation tube bundle 2 to obtain an intermediate product B 'at the top of the tower, and the heavy component with stronger polarity is remained in a liquid phase under the action of capillary force (namely, adsorbed on the tube wall) to obtain an intermediate product C' at the bottom of the tower, so that the gas-liquid balance of the azeotrope in the azeotropic mixed solution A is changed. Finally, the gasified and ascending light component (namely the intermediate product B ') is condensed at the top of the rectifying composite tower 1 and then enters the tower tray 3 from top to bottom, the heavy component (namely the intermediate product C') remained in the liquid phase enters the tower tray from bottom to top after being reboiled at the bottom of the tower, and the gas-liquid two phases carry out heat and mass transfer on the tower tray 3, thereby completing the whole rectifying process. Aiming at the problems that the prior azeotropic separation method needs to add a third-party solvent to cause the limitation of a separation system, and the traditional rectification method can not change the relative volatility between the solutions of the azeotropic system to cause the low azeotropic separation efficiency and the like, the invention utilizes the different acting forces of the capillary metal tube bundle on different polar components in the solution of the azeotropic system to break through the azeotropic point under the azeotropic solution. The difference of the polarity in the invention means that the adsorption capacity of different components on the pipe wall is different due to the difference of the molecular composition and the group structure of the components in the solution. Namely, the heavy component with strong polarity is remained in the liquid phase under the action of capillary force (namely, the adsorption capacity of the tube wall), the light component with weak polarity enters the top of the tower after gasification, so that the gas-liquid balance of the azeotrope is changed, the azeotropic point under the azeotropic solution is broken through, the azeotropic system can be separated without adding a third-party solvent, and meanwhile, the application range of the azeotropic system to materials is wide, and the energy consumption for separation is low.

Further, in order to ensure the separation efficiency, the feed of the azeotropic mixture solution a is fed to the middle of the capillary rectification tube bundle 2 so that the rising gas phase and the falling liquid phase have sufficient strokes. Preferably, but not limitatively, to prevent the capillary rectification tube bundle 2 from being excessively clogged by the rising bubbles, the light components with weak polarity may be subjected to a bubble breaking step during the vaporization rising in the capillary rectification tube bundle. Further, the pressure in the rectification composite tower 1 is 0.1MPa to 10 MPa; the temperature in the rectification composite tower is 20 ℃ to 600 ℃.

The azeotropic mixed solution is heated to a bubble point and then is fed into a capillary rectification tube bundle from a capillary rectification composite tower as a capillary rectification composite tower, light components with weaker polarity rise to the top of the capillary rectification area tower under the action of capillary force, all intermediate products B' at the top of the tower enter a tower top condenser, and the discharge of the tower top condenser is pressurized by a pump (namely a tower top reflux pump 5) and then circulates to the top of the tower body. Heavy components with strong polarity enter the tower bottom of the capillary rectification area, all the intermediate products C' at the tower bottom enter a tower bottom reboiler, and the tower bottom reboiler discharges materials which are pressurized by a tower bottom circulating pump 6 and then circulate to the bottom of the tower body. And gas-liquid two phases of the intermediate product B 'at the top of the tower and the intermediate product C' at the bottom of the tower are subjected to heat and mass transfer on a tower tray, the final product B at the top of the tower is extracted from the top of the tower to be taken as a light product and is discharged out of the tower body, and the final product C at the bottom of the tower is extracted from the bottom of the tower to be taken as a heavy product and is discharged out of the tower body. The device and the method are suitable for rectifying the azeotropic mixed solution with weak light component polarity and strong heavy component polarity.

Examples

The ethyl acetate-ethanol azeotropic solution enters the capillary rectification tube bundle 2 in a bubble point state, ethyl acetate with weaker polarity is gasified and then goes upwards, and enters the tower top condenser 4 through the capillary rectification tube bundle 2, and the condensed higher-concentration light component ethyl acetate-ethanol solution is pressurized by the tower top reflux pump 5 and then circulates to the tower body of the rectification composite tower 1 and flows from top to bottom from the stripping section tower tray 3; the ethanol with stronger polarity is kept in a liquid phase under the action of capillary force, moves towards the lower end of the capillary rectification tube bundle 2 under the action of gravity, is pressurized by a tower bottom circulating pump 6 and then enters a tower bottom reboiler 7, the gasified ethyl acetate-ethanol mixed steam with lower concentration circulates to the bottom of the stripping section tower tray 3, the conventional heat and mass transfer is completed on the stripping section tower tray 3, finally, a high-concentration ethyl acetate product is obtained at the top of the stripping section tower tray 3, and a high-concentration ethanol product is obtained at the bottom of the stripping section tower tray 3. In the above embodiment, the capillary rectifying tube bundle 2 is made of stainless steel, the stripping section tray 3 is a sieve plate tower, the temperature of the condenser at the top of the tower is 45 ℃, the temperature of the reboiler at the bottom of the tower is 100 ℃, and the pressure is 0.16 MPa.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. Any simple modifications, equivalent changes and modifications made to the above exemplary embodiments shall fall within the scope of the present invention.