A bundled tube type reaction rectification separation device and method

Abstract

The present application relates to a kind of bundled tube type reaction rectification separation device and method, the separation device includes tower main body, separation tower section being arranged in the middle region of the tower main body, and be located above and below the liquid redistributor and kettle liquid collector in the tower main body and respectively in the separation tower section, the separation tower section includes several parallelly arranged reaction rectification column, each reaction rectification column is sequentially connected by the lower section of packing, catalytic reaction section and upper section of packing from bottom to top, the lower section of packing and the upper section of packing are connected with the kettle liquid collector and liquid redistributor respectively.Compared with prior art, the present application is by the parallelly arranged tube type rectification separation column, not only realize the precise separation effect under high throughput;Simultaneously by setting catalytic reaction section and rectification section, improve the coupling synergistic effect between the catalytic conversion and rectification separation of light component and heavy component in the to-be-separated system.

Description

Technical Field

[0001] This invention belongs to the field of distillation and separation technology, and relates to a bundled tube type reactive distillation and separation device and method. Background Technology

[0002] Distillation is the most widely used method for separating mixtures in industry. Based on differences in the distillation process, it can be divided into various distillation operation modes. The process of coupling chemical reaction and distillation separation in the same device is called reactive distillation. In reactive distillation, on the one hand, a catalytic reaction promotes the conversion between reactants and products, creating a concentration difference; on the other hand, through distillation separation, continuous interactions between the gas and liquid phases occur, causing heavy components to concentrate in the bottom of the column and light components to accumulate at the top, thus achieving continuous separation of reactants and products. Therefore, the coupling effect of catalytic reaction and distillation separation can accelerate the breaking of chemical equilibrium, improve conversion rate, and enhance the separation efficiency of light and heavy components.

[0003] In existing traditional reactive distillation devices (such as the catalytic reactive distillation separation device provided by Chinese patent CN105294382B), the main approach is to alternately fill the packing section and the reaction section, or to mix the packing and catalyst together and uniformly fill them in the separation column. Due to the non-uniform distribution effects of channeling and wall flow on the surface of the packing in the distillation column, the packing surface cannot be completely wetted, affecting separation efficiency. Similarly, in the catalytic reaction section, there is a non-uniform distribution of gas and liquid phases in both the radial and axial directions, which also reduces the conversion efficiency of the catalytic reaction section. Furthermore, for some heat-sensitive systems, in addition to the reduction in conversion and separation efficiency, the non-uniform distribution of reactants and the channeling effect can easily lead to localized high reactant concentrations in certain parts of the catalytic reaction section, causing violent reactions, localized overheating, coking, or even blockage, making it impossible for the entire system to operate stably for a long period. Summary of the Invention

[0004] The purpose of this invention is to provide a bundled tube reactive distillation separation device and method, which solves the problem of scale-up effect in traditional reactive distillation, achieves a more uniform distribution of gas-liquid phase flow field and temperature field, and improves reactant conversion rate and separation efficiency.

[0005] The objective of this invention can be achieved through the following technical solutions: In a first aspect, the present invention provides a bundled tube type reactive distillation separation device, comprising a column body, a separation column section disposed in the middle region of the column body, and a liquid redistributor and a bottom liquid collector disposed within the column body and respectively located above and below the separation column section. The separation column section comprises a plurality of reactive distillation columns arranged in parallel, each reactive distillation column consisting of a lower packing section, a catalytic reaction section and an upper packing section connected sequentially from bottom to top. The lower packing section and the upper packing section are respectively connected to the bottom liquid collector and the liquid redistributor.

[0006] Furthermore, the reactive distillation columns have the same diameter, and their diameter D satisfies: 30mm≤D≤100mm.

[0007] Furthermore, each reactive distillation column has the same height, and its height H satisfies: 1.5m≤D≤5m; each reactive distillation column consists of a lower packing section, a catalytic reaction section, and an upper packing section, wherein the height of the catalytic reaction section accounts for 1 / 3 to 1 / 2 of the height of the reactive distillation column, and the lower packing section and the upper packing section have the same height.

[0008] Furthermore, in the reactive distillation column, one of the columns is located at the center line of the separation column section, and the remaining reactive distillation columns are evenly distributed around the center line.

[0009] Furthermore, the reactive distillation column located at the central axis is spaced at the same distance from the surrounding adjacent reactive distillation columns, and the distance d satisfies: 10mm≤d≤30mm.

[0010] Furthermore, in the reactive distillation column, the void fraction α of the reactive distillation column, which consists of a lower packing section, a catalytic reaction section, and an upper packing section, satisfies the following condition: 70% ≤ α ≤ 95%.

[0011] Furthermore, the liquid redistributor has several distribution holes of the same diameter at the interface between it and the upper section of the packing.

[0012] Furthermore, the diameter of the distribution holes is the same, and is 0.5~5mm.

[0013] Furthermore, the liquid redistributor and the bottom liquid collector are in close contact with the top and bottom of each reactive distillation separation column section to minimize the impact of column section wall flow.

[0014] In a second aspect, the present invention provides a bundled tube reactive distillation separation method, which is implemented based on the bundled tube reactive distillation separation device described in the first aspect above. The method is characterized in that the gaseous fluid generated by heating at the bottom of the reactive distillation column flows upwards, while the liquid fluid formed by condensation at the top of the column flows downwards under gravity. The gaseous and liquid fluids are in contact with each other within each reactive distillation column. Catalytic mass transfer occurs in the catalytic reaction section, and separation mass transfer occurs at the upper and lower sections of the packing. This allows heavy components in the gaseous phase to be enriched in the liquid phase, while light components in the liquid phase enter the gaseous phase for concentration, thereby achieving a coupled and synergistic effect of "reaction and distillation separation".

[0015] Furthermore, it is applicable to the production of stable isotope D2O and heavy oxygen water by vacuum water distillation in the bundled tube reactive distillation separation device using natural water as raw material, through the coupled mass transfer effect of hydrogen-deuterium isotope catalytic conversion and distillation separation. Alternatively, it is applicable to the use of natural CO or CO2 as raw materials, in the bundled tube reactive distillation separation device, to achieve the production of stable isotopes by low-temperature distillation through the coupled mass transfer effect of catalytic conversion between carbon isotopes and distillation separation. 13 CO 13 CO2.

[0016] wait.

[0017] Compared with the prior art, the present invention has the following advantages: (1) The parallel structure of small-diameter tubular reactive distillation columns avoids local violent reactions for heat-sensitive systems and flammable and explosive separation systems, making them safer and more reliable, and also extending the service life of the catalyst.

[0018] (2) Unlike the channeling and wall flow phenomena that exist in traditional single large-diameter distillation columns, the present invention adopts a parallel arrangement of small-diameter reactive distillation columns with the center and surrounding uniform distribution, which solves the scale-up effect of distillation operation, effectively reduces channeling and wall flow phenomena, and improves distillation separation efficiency.

[0019] (3) This invention improves the synergistic effect of catalytic conversion and distillation separation operations. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the bundled tube reactive distillation separation device of the present invention; Figure 2 This is a top view of a separation column section consisting of five tubular reactive distillation columns connected in parallel. Explanation of markings in the diagram: 1-Packed section, 2-Catalytic reaction section, 3-Liquid distributor, 4-Pot liquid collector, 5-Separation tower section, 6-Reactive distillation column, 7-Redistribution orifice. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0022] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] Unless otherwise specified, the functional components or structures in the following embodiments or examples are conventional components or structures used in the art to achieve the corresponding functions.

[0025] To address the scale-up challenges of traditional reactive distillation and achieve a more uniform distribution of the gas-liquid phase flow field and temperature field, thereby improving reactant conversion and separation efficiency, this invention provides a bundled tube reactive distillation separation device. The device includes a column body, a separation column section disposed in the middle region of the column body, and a liquid redistributor and a bottom liquid collector disposed within the column body and respectively located above and below the separation column section. The separation column section comprises several reactive distillation columns arranged in parallel. Each reactive distillation column consists of a lower packing section, a catalytic reaction section, and an upper packing section connected sequentially from bottom to top. The lower packing section and the upper packing section are respectively connected to the bottom liquid collector and the liquid redistributor.

[0026] In some specific embodiments, the reactive distillation columns have the same diameter, and their diameter D satisfies: 30mm≤D≤100mm.

[0027] In some specific embodiments, each reactive distillation column has the same height, and its height H satisfies: 1.5m≤D≤5m; each reactive distillation column consists of a lower packing section, a catalytic reaction section and an upper packing section, wherein the height of the catalytic reaction section accounts for 1 / 3 to 1 / 2 of the height of the reactive distillation column, and the lower packing section and the upper packing section have the same height.

[0028] In some specific embodiments, one of the reactive distillation columns is located at the centerline of the separation column section, and the remaining reactive distillation columns are evenly distributed around the centerline.

[0029] In some specific implementations, the reactive distillation column located at the central axis is spaced at the same distance from the surrounding adjacent reactive distillation columns, and the distance d satisfies: 10mm≤d≤30mm.

[0030] In some specific embodiments, the reactive distillation column, which consists of a lower packing section, a catalytic reaction section, and an upper packing section, has a porosity α that satisfies the following condition: 70% ≤ α ≤ 95%.

[0031] In some specific embodiments, the liquid redistributor has several distribution holes of the same diameter at the interface between it and the upper section of the packing.

[0032] In a more specific embodiment, the diameter of the distribution holes is the same and is 0.5~5mm.

[0033] In some specific implementations, the liquid redistributor and the bottom liquid collector are in close contact with the top and bottom of each reactive distillation separation column section to minimize the impact of column section wall flow.

[0034] Each of the above implementation methods can be implemented individually, or in any combination of two or more without violating logic.

[0035] The above implementation methods will be described in more detail below with reference to specific embodiments.

[0036] Example 1: The bundled tube reactive distillation separation device used in this embodiment is for the production of stable isotope D2O by vacuum water distillation, such as... Figure 1 As shown, it includes a liquid redistributor, a reactive distillation column, and a bottom liquid collector. In this embodiment, the stable isotope D2O separation column contains a total of 10 sections, such as... Figure 1The separation column section shown is composed of five identical reactive distillation columns connected in parallel. One reactive distillation column is located at the center of the section, with the other four tubular reactive distillation columns evenly distributed on either side. Each reactive distillation column includes two rectification sections and one reaction section, with the reaction section located in the middle of the column and filled with a supported noble metal Pd-type catalyst for the hydrogen isotope-deuterium isotope exchange reaction. Each reactive distillation column is 5 meters high, with the reaction section being 2 meters high; each reactive distillation column has a diameter of DN80, and the pores at the top redistribution point have a diameter of Φ3, achieving a porosity of 75%.

[0037] Using the bundled tube reactive distillation apparatus designed in this embodiment, the material vapor generated by heating at the bottom of the reactive distillation column flows upward, while the liquid aqueous solution formed by condensation in the top condenser of the reactive distillation column flows downward under gravity. The gas phase and liquid phase fluids come into contact with each other in each reactive distillation column. Under the action of a supported noble metal Pd-type catalyst, a hydrogen-deuterium exchange reaction is achieved. Separation and mass transfer occur at the upper and lower sections of the packing, which enriches the deuterium isotope component in the gas phase into the liquid phase, while the hydrogen component in the liquid phase enters the gas phase for concentration, thereby achieving the separation of hydrogen and deuterium isotopes. Furthermore, for achieving the D2O separation target of 99% abundance, if a separation device of the same height is used, the bundled tube reactive distillation device designed in this embodiment improves the hydrogen-deuterium isotope separation efficiency by 52% compared to a traditional vacuum water distillation column without a catalytic reaction section; compared to a traditional single reactive distillation column, the hydrogen-deuterium isotope separation efficiency is improved by 25%, fully demonstrating the synergistic effect of catalytic conversion and distillation mass transfer separation coupling described in this embodiment.

[0038] Comparative Example 1: This comparative example uses a bundled-tube reactive distillation separation apparatus for the production of stable isotope D₂O via vacuum water distillation. It includes a liquid redistributor, a reactive distillation column, and a bottom liquid collector. In this comparative case, the stable isotope D₂O separation column contains 10 separation column sections. Unlike Example 1, each separation column section is a reactive distillation column, and each column includes two rectification sections and one reaction section. The reaction section is located in the middle of the column and is filled with a supported noble metal Pd-type catalyst for the hydrogen isotope-deuterium isotope exchange reaction. Each reactive distillation column is 5 meters high, with the reaction section being 2 meters high. Each separation column section has a diameter of DN150; the top redistribution pores have a diameter of Φ3 and a porosity of 75%.

[0039] Comparative Example 2: The bundled-tube reactive distillation separation device used in this comparative example is employed for the production of the stable isotope D₂O via vacuum water distillation. Figure 1 As shown, it includes a liquid redistributor, a reactive distillation column, and a bottoms collector. In this comparative case, the stable isotope D2O separation column contains a total of 10 sections, such as... Figure 1 The separation column section shown is composed of five identical reactive distillation columns connected in parallel. One reactive distillation column is located at the center of the section, with the other four tubular reactive distillation columns evenly distributed on either side. Each reactive distillation column includes two rectification sections and one reaction section, with the reaction section located in the middle of the column and filled with a supported noble metal Pd-type catalyst for the hydrogen isotope-deuterium isotope exchange reaction. Each reactive distillation column is 5 meters high, with the reaction section being 4 meters high; each reactive distillation column has a diameter of DN80, and the pores at the top redistribution point have a diameter of Φ3, achieving a porosity of 75%.

[0040] Comparative Example 3: The bundled-tube reactive distillation separation device used in this comparative example is employed for the production of the stable isotope D₂O via vacuum water distillation. Figure 1 As shown, it includes a liquid redistributor, a reactive distillation column, and a bottoms collector. In this comparative case, the stable isotope D2O separation column contains a total of 10 sections, such as... Figure 1 The separation column section shown is composed of three identical reactive distillation columns connected in parallel. One reactive distillation column is located at the center of the section, with the other two tubular reactive distillation columns evenly distributed on either side. Each reactive distillation column includes two rectification sections and one reaction section, with the reaction section located in the middle of the column and filled with a supported noble metal Pd-type catalyst for the hydrogen isotope-deuterium isotope exchange reaction. Each reactive distillation column is 5 meters high, with the reaction section being 2 meters high; each reactive distillation column has a diameter of DN125, and the pores at the top redistribution point have a diameter of Φ3, achieving a porosity of 75%.

[0041] Table 1. Comparison of separation performance data between each embodiment and the comparative example. As can be seen from the comparison in Table 1, the bundled tube reactive distillation separation device designed in this invention improves the hydrogen-deuterium isotope separation efficiency by more than 50% compared with the conventional vacuum water distillation column. Under the condition of the same total amount of catalyst loaded in the reactive distillation separation device, compared with Comparative Examples 1 to 3, this invention also has a significant efficiency advantage, with a significant performance improvement, meeting the technical requirements for high separation efficiency in the field of stable isotope separation.

[0042] Example 2 A bundled tube reactive distillation separation device is used to produce heavy oxygen water (H2) by vacuum water distillation. 18 O) stable isotopes, each reactive distillation column section includes a liquid redistributor, a distillation separation column, and a bottoms collector. In this implementation case, heavy oxygen water (H2) 18 O) The stable isotope separation column contains 15 sections, such as Figure 1The separation column section is shown. Each separation column section consists of five identical reactive distillation columns connected in parallel. One reactive distillation column is located at the center of the section, and the other four tubular reactive distillation columns are evenly distributed on both sides of it. (Viewed from above, as shown...) Figure 2 As shown. Each reactive distillation column comprises two rectifying sections and one reaction section, with the reaction section located in the middle of the column and filled with oxygen-16 (…). 16 O) isotopes and oxygen-18 ( 18 O) Supported noble metal Pt catalyst for isotope exchange reaction. Each reactive distillation column is 4 meters high, with a reaction section of 1.5 meters; each reactive distillation column has a diameter of DN65, and the redistribution pores at the top have a pore size of Φ2.5, achieving a porosity of 80%.

[0043] Using the bundled tube reactive distillation apparatus designed in this embodiment, the material vapor generated by heating at the bottom of the reactive distillation column flows upward, while the liquid aqueous solution formed by condensation in the condenser at the top of the column flows downward under gravity. The gas and liquid phases are in contact with each other within each reactive distillation column, where stable isotopes are achieved under the action of a supported noble metal Pd-type catalyst. 16 O- 18 O-exchange reaction, separation and mass transfer occur at the top and bottom of the packing material, allowing the gas phase to... 18 O isotope components are enriched in the liquid phase, and in the liquid phase... 16 The O isotope component is concentrated in the gas phase, thereby achieving stable isotopes. 16 O and 18 The separation of O2. Furthermore, for heavily oxygenated water (H2) reaching an abundance of 99%. 18 O) Separation target: If a separation device of the same height is used, the bundled tube reactive distillation device designed in this embodiment, compared with the traditional vacuum water distillation column without a catalytic reaction section, 18 The efficiency of O isotope separation was improved by 45%; compared with traditional single reactive distillation columns, 18 The separation efficiency of O isotopes was increased by 20%, which fully demonstrates the synergistic effect of the coupling of catalytic conversion and distillation mass transfer separation described in this embodiment.

[0044] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A bundled tube type reactive distillation separation device, characterized in that, The system includes a main column, a separation column section located in the middle region of the main column, and a liquid redistributor and a bottom liquid collector located within the main column and respectively above and below the separation column section. The separation column section includes several reactive distillation columns arranged in parallel. Each reactive distillation column consists of a lower packing section, a catalytic reaction section, and an upper packing section connected sequentially from bottom to top. The lower packing section and the upper packing section are respectively connected to the bottom liquid collector and the liquid redistributor.

2. The bundled tube type reactive distillation separation device according to claim 1, characterized in that, The reactive distillation columns have the same diameter, and their diameter D satisfies: 30mm≤D≤100mm.

3. The bundled tube type reactive distillation separation device according to claim 1, characterized in that, Each reactive distillation column has the same height, and its height H satisfies: 1.5m ≤ D ≤ 5m; Each reactive distillation column consists of a lower packing section, a catalytic reaction section, and an upper packing section. The height of the catalytic reaction section accounts for 1 / 3 to 1 / 2 of the total height of the reactive distillation column, while the lower and upper packing sections are of the same height.

4. The bundled tube type reactive distillation separation device according to claim 1, characterized in that, Of the reactive distillation columns, one is located at the center line of the separation column section, and the remaining reactive distillation columns are evenly distributed around the center line.

5. A bundled tube type reactive distillation separation device according to claim 1, characterized in that, The reactive distillation column located at the central axis is equidistant from its adjacent reactive distillation columns, and the spacing d satisfies: 10mm≤d≤30mm.

6. The bundled tube type reactive distillation separation device according to claim 1, characterized in that, The void ratio α of the reactive distillation column satisfies: 70% ≤ α ≤ 95%.

7. The bundled tube type reactive distillation separation device according to claim 1, characterized in that, The liquid redistributor has several distribution holes of the same diameter at the interface between it and the upper section of the packing.

8. A bundled tube type reactive distillation separation device according to claim 7, characterized in that, The diameters of the distribution holes are all the same and range from 0.5 to 5 mm.

9. A bundled-tube reactive distillation separation method, implemented based on the bundled-tube reactive distillation separation apparatus as described in any one of claims 1-8, characterized in that, The gaseous fluid generated by heating at the bottom of the column body flows upward, while the liquid fluid formed by condensation at the top of the column body flows downward under the action of gravity. The gaseous and liquid fluids come into contact with each other in each reactive distillation column. Catalytic mass transfer occurs in the catalytic reaction section, and separation mass transfer occurs at the top and bottom of the packing. This allows the heavy components in the gas phase to be enriched in the liquid phase, while the light components in the liquid phase enter the gas phase for concentration, thereby achieving a coupled and synergistic effect of reaction and distillation separation.

10. The bundled tube reactive distillation separation method according to claim 9, characterized in that, It is applicable to the production of stable isotope D2O and heavy oxygen water by vacuum water distillation in the bundled tube type reactive distillation separation device using natural water as raw material, through the coupled mass transfer effect of hydrogen-deuterium isotope catalytic conversion and distillation separation. Alternatively, it is applicable to the use of natural CO or CO2 as raw materials, in the bundled tube reactive distillation separation device, to achieve the production of stable isotopes by low-temperature distillation through the coupled mass transfer effect of catalytic conversion between carbon isotopes and distillation separation. 13 CO 13 CO2.

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