Supergravity bidirectional rotating bed device based on end effect region

Abstract

A supergravity bidirectional rotating bed device based on an end effect zone comprises a shell, a first rotating disc and a second rotating disc, a plurality of first fillers are concentrically arranged on the first rotating disc, a plurality of second fillers are concentrically arranged on the second rotating disc, and the first fillers and the second fillers are annular and are concentrically distributed; the first filler and the second filler are mutually nested and distributed in a staggered manner at intervals; a liquid distributor is arranged in the center of the shell and used for spraying liquid to the first filler or the second filler on the innermost side, and a liquid phase outlet is formed in the bottom of the shell; a gas distributor is arranged on the periphery of the first filler or the second filler located on the outermost side in the shell, a gas inlet distributed towards the gas distributor is formed in the side portion of the shell, and a gas rising hole allowing gas to rise and be exhausted from a gas outlet formed in the top of the shell is formed in the center of the second rotary disc. The space utilization efficiency and the mass transfer efficiency of the filler area can be improved, and the overall mass transfer performance of the supergravity rotating bed is improved.

Description

Technical Field

[0001] The present invention relates to the field of high-gravity rotating beds, and specifically to a high-gravity two-way rotating bed device based on the end effect region. Background Art

[0002] A high-gravity rotating bed is a new type of equipment that uses a centrifugal force field to replace the gravity field to strengthen the molecular diffusion between molecules and the interfacial contact between phases, thereby strengthening the mass transfer process. It has the advantages of small equipment volume, low energy consumption, convenient start-up and shutdown, and small liquid holdup, and is widely used in the fields of distillation, absorption, separation, chemical precipitation, and oxidation.

[0003] There is a special phenomenon in the high-gravity rotating bed compared with traditional gas-liquid mass transfer equipment such as packed towers and plate towers, that is, the high-gravity rotating bed has an end effect region. The so-called end effect region refers to a small section of the inner edge of the rotor packing (i.e., the radial thickness of the packing is about 10-30 mm), and the mass transfer in this region accounts for a large proportion of the total mass transfer of all packings. The mass transfer contribution in the end effect region is several times that of other regions of the rotor packing, and it is the core region of the overall mass transfer.

[0004] The reason why the end effect region can strengthen mass transfer is that before the liquid enters the end effect region, the circumferential velocity is zero and the radial velocity is the largest. When the liquid collides with the packing with a large circumferential velocity at the inner edge of the packing, the relative velocity between the liquid and the packing is the largest at this time, and the collision and shear of the packing on the liquid are the most intense. The liquid is dispersed into tiny droplets, and the specific surface area of the liquid increases sharply, providing a sufficient interface for gas-liquid mass transfer and reaction. After the liquid flows through the end effect region, the liquid (droplets, liquid films or liquid filaments) obtains a circumferential velocity similar to that of the packing, resulting in a decrease in the relative velocity between the liquid and the packing, weakening the collision and cutting, and the liquid can quickly move with the packing in the form of a relatively stable liquid film and be thrown out of the packing under the action of centrifugal force.

[0005] Chinese Patent CN102258880B discloses a high-gravity rotating bed device for strengthening the end effect of the rotor by segmented liquid inlet. By arranging multiple layers of annular packing layers in the cavity and arranging liquid inlet spray pipes between adjacent annular packing layers for segmented liquid distribution, multiple end effect regions are formed, and the flow flux of the packing is kept roughly unchanged to achieve the purpose of efficient mass transfer. However, the spray pipes involved in this invention will occupy a large amount of space between the packing layers, reducing the packing space. Moreover, due to segmented liquid inlet and liquid supplementation, the untransferred liquid near the outside and the fully mass-transferred liquid inside are mixed, which will also reduce the mass transfer driving force and result in poor mass transfer effect. CN 114632487A discloses a microchannel high-gravity rotating bed, which uses the nested method of the stator and the rotor to form microchannels in the annulus to increase the gas-liquid contact area. However, this method will cause a very large pressure drop between the gas-liquid two phases, a very high fluid flow resistance, and a very large resistance to the movement of the rotor. Summary of the Invention

[0006] The present invention aims to provide a high-gravity two-way rotating bed device based on an end effect region, improve the space utilization efficiency and mass transfer efficiency of the packing region, and enhance the overall mass transfer performance of the high-gravity rotating bed.

[0007] To solve the above technical problems, the specific solution adopted by the present invention is as follows: A high-gravity two-way rotating bed device based on an end effect region, comprising a housing, a first rotating disk rotatably arranged at the bottom of the housing, and a second rotating disk rotatably arranged at the top of the housing. A plurality of first packings are concentrically arranged on the first rotating disk, and a plurality of second packings are concentrically arranged on the second rotating disk. The first packings and the second packings are both annular and concentrically distributed, and the first packings and the second packings are nested and alternately distributed at intervals;

[0008] A liquid distributor is arranged at the central position of the housing, and the liquid distributor is used to spray liquid onto the innermost first packing or second packing. A liquid phase outlet is arranged at the bottom of the housing; A gas distributor is arranged on the outer periphery of the outermost first packing or second packing in the housing. A gas inlet distributed towards the gas distributor is arranged on the side of the housing. An upflow hole for the gas to flow up and be discharged from a gas outlet arranged at the top of the housing is arranged at the central position of the second rotating disk.

[0009] Preferably, the housing, the first rotating disk, and the second rotating disk are all circular and concentrically distributed.

[0010] Preferably, drive shafts extending to the outside of the housing are arranged at the centers of the first rotating disk and the second rotating disk, and the drive shafts are in transmission connection with a drive motor.

[0011] Preferably, the drive shafts of the first rotating disk and the second rotating disk are in transmission connection with the same drive motor.

[0012] Preferably, both the first packings and the second packings are wire mesh packings.

[0013] Preferably, the first packings and the second packings have the same porosity, and the porosity is 90 - 96%.

[0014] Preferably, the first packings and the second packings have different porosities, and the porosity is 90 - 96%

[0015] Preferably, the first packings and the second packings have the same thickness, and the thickness is 5 - 30 mm.

[0016] Preferably, the first packings and the second packings have different thicknesses, and the thickness is 5 - 30 mm

[0017] Preferably, a liquid pipeline connected to the liquid distributor is rotatably fitted at the center of the first rotating disk, and a U-shaped seal is arranged between the liquid pipeline and the first rotating disk.

[0018] Preferably, the second rotating disk is in clearance fit with the top wall of the housing, and an annular seal is arranged between the top of the outer edge of the second rotating disk and the top wall of the housing.

[0019] Preferably, the gas distributor is provided with uniform or non-uniform gas holes for gas passage.

[0020] In view of the existing problems in the technology of the high-gravity rotating bed, the present invention creates multiple end-effect zones by adopting the method of bidirectional rotation of multi-stage packings, thereby improving the space utilization efficiency and mass transfer efficiency of the packing zone. When the gas-liquid flows through adjacent packings, the movement trajectory changes suddenly, obtaining a larger gas-liquid contact area, thereby improving the overall mass transfer performance of the high-gravity rotating bed. Compared with the existing related technologies, the present invention has the following advantages:

[0021] First, high mass transfer efficiency. The present invention has multiple end-effect zones, and the rotation directions of adjacent packing layers are opposite, which can create a large contact area and improve the mass transfer efficiency of the entire high-gravity rotating bed by 50% to 70%.

[0022] Second, low energy consumption. Although it is necessary to drive two turntables (the first turntable and the second turntable) to rotate in the present invention, due to the opposite rotation directions of the first turntable and the second turntable, a very good liquid-phase dispersion effect can be obtained at a relatively low rotational speed for each single turntable. While ensuring the mass transfer effect (the number of end-effect zones), it has the advantage of low energy consumption.

[0023] Third, low gas-phase pressure drop. When the turntable operates at a relatively low rotational speed, the centrifugal force generated on the gas is small, and the resistance that the gas phase needs to overcome when flowing through the packing is small. Therefore, compared with the traditional high-gravity rotating bed, it has the advantage of low gas-phase pressure drop. Description of the Drawings

[0024] Figure 1 It is a schematic cross-sectional structure diagram of a high-gravity bidirectional rotating bed device based on end-effect zones of the present invention;

[0025] Figure 2 It is a partial enlarged schematic diagram of the U-shaped seal part between the first turntable and the liquid pipeline in the present invention;

[0026] Figure 3 It is a schematic top view structure diagram of the second turntable and two specifications of gas lifting holes thereon in the present invention;

[0027] Reference numerals in the drawings: 1, liquid-phase outlet; 2, housing; 3, U-shaped seal; 4, liquid pipeline; 5, liquid distributor; 6, first turntable; 7, first packing; 8, gas distributor; 9, gas inlet; 10, annular seal; 11, second packing; 12, gas lifting hole; 13, gas outlet; 14, second turntable. Detailed Embodiments

[0028] A supergravity bi-directional rotating bed device based on an end effect region, having a cylindrical housing 2. At the bottom of the housing 2, a first turntable 6 is provided, and at the top, a second turntable 14 is provided. Both the first turntable 6 and the second turntable 14 are circular and concentrically distributed with the housing 2. Driving shafts are also respectively provided on the first turntable 6 and the second turntable 14. The two driving shafts respectively extend outside the housing 2 and are connected to the same driving motor. The output shaft of the driving motor directly drives the first turntable 6 to rotate, and drives the second turntable 14 to rotate at the same speed in the opposite direction through a conventional direction-changing mechanism such as an idler wheel in the art.

[0029] Three first packings 7 are provided along the upper edge of the first turntable 6, and two second packings 11 are provided along the lower edge of the second turntable 14. All the first packings 7 and the second packings 11 are concentrically distributed, and are distributed in an alternating and nested manner at intervals. The first packings 7 and the second packings 11 respectively rotate synchronously with the corresponding first turntable 6 and second turntable 14, and the rotation directions of the first packings 7 and the second packings 11 are opposite.

[0030] Both the first packings 7 and the second packings 11 are wire mesh packings. The porosity of the first packings 7 and the second packings 11 is the same, and is 90-96%. In other embodiments of the present invention, the first packings 7 and the second packings 11 may also be different. The single-layer radial thickness range of the first packings 7 and the second packings 11 is 5-30 mm. In other embodiments of the present invention, the radial thickness of the packings may also be different.

[0031] A liquid distributor 5 is provided at the central position of the innermost first packing 7 in the housing 2, and a liquid phase outlet 1 for discharging liquid is provided at the bottom of the housing 2. The liquid distributor 5 is used to directly inject liquid into the innermost first packing 7. A liquid pipeline 4 penetrates through the central position of the first turntable 6. The upper end of the liquid pipeline 4 is connected to the liquid distributor 5, and the lower end passes through the hollow driving shaft on the first turntable 6 and is connected to a liquid source. To prevent leakage between the liquid pipeline 4 and the first turntable 6 during relative rotation, as Figure 2 shown, a U-shaped seal 3 is provided along the upper edge of the first turntable 6 and at the position outside the circumference of the liquid pipeline 4.

[0032] A gas distributor 8 is provided on the outer circumference of the first turntable 6 and the second turntable 14 in the housing 2. A gas inlet 9 facing the gas distributor 8 is provided on the side wall of the housing 2. The gas distributor 8 is provided with uniformly or non-uniformly distributed holes for the gas introduced from the gas inlet 9 to pass through the first packings 7 and the second packings 11 in the direction from the outside to the inside until the middle of the innermost first packing 7. At the same time, the gas distributor 8 also plays a role in preventing liquid splashing to a certain extent. A plurality of air lifting holes 12 are also provided at the middle position of the second turntable 14. The air lifting holes 12 are for the gas entering the inside of the first packing 7 to rise through and be discharged from a gas outlet 13 provided at the top of the housing 2. As Figure 3As shown, the shape of the gas lifting hole 12 in the present invention can be set as a sector, a circle or other shapes. In addition, since there is a clearance fit between the second rotating disk 14 and the top wall of the housing 2 in the present invention, in order to prevent gas from short - circuiting at the position between the second rotating disk 14 and the top wall of the housing 2, an annular seal 10 is also provided between the outer edge of the second rotating disk 14 and the top wall of the housing 2 in the present invention.

[0033] The specific working process of the present invention is as follows:

[0034] Driven by an external driving motor, the first rotating disk 6, the second rotating disk 14 and the first packing 7 and the second packing 11 fixed thereto rotate together. The rotating directions of the first rotating disk 6 and the first packing 7 are opposite to those of the second rotating disk 14 and the second packing 11. Liquid enters the high - gravity rotating bed from the liquid pipeline 4, is sprayed by the liquid distributor 5, and is evenly distributed on the inner side of the innermost layer of the first packing 7. At this time, the circumferential velocity of the liquid is zero and the radial velocity is the largest. The liquid collides with the first packing 7 with a very large circumferential velocity at the innermost layer of the first packing 7. The relative velocity between the liquid and the first packing 7 is the largest, and the collision and shear of the first packing 7 on the liquid are the most intense. The liquid is dispersed into tiny droplets, and the specific surface area increases sharply, thus forming an end - effect zone in the packing area. Subsequently, the liquid flows through and detaches from the innermost layer of the first packing 7. At this time, the liquid has a circumferential velocity similar to that of the innermost layer of the first packing 7. The liquid impacts the next - layer second packing 11 with a very high circumferential velocity and a certain radial velocity. Since the rotating direction of the next - layer second packing 11 is opposite to that of the upper - layer first packing 7, there is a very large relative velocity between the liquid and the next - layer second packing 11. The collision and shear of the next - layer second packing 11 on the liquid are intense, and the specific surface area of the liquid increases again, forming an end - effect zone again in the area of the next - layer second packing 11. This is repeated. Every time the liquid detaches from a layer of packing, an end - effect zone will be formed in the next - layer packing until the liquid phase leaves the packing and flows out from the liquid phase outlet 1.

[0035] Gas enters the high - gravity rotating bed from the gas phase inlet, is evenly distributed by the gas distributor 8 and then enters the outermost layer of the first packing 7, contacts and mass - transfers with the reversely flowing liquid, and flows inward to the inner - layer packing step by step under the action of pressure, and finally reaches the inside of the high - gravity rotating bed and is discharged from the gas outlet 13 through the gas lifting hole 12.

[0036] In a specific application embodiment of the present invention, a NaOH solution is used to absorb CO2 gas. The radial thickness of the first packing 7 is 15 mm, which is arranged in three layers. The single-layer radial thickness of the second packing 11 is 15 mm, which is arranged in two layers. Both use wire mesh packing, and the packing porosity is 94%. The gas distributor 8 is evenly provided with circular holes with a pore diameter of 5 mm, arranged in an equilateral triangle distribution, and the hole opening rate is 27%. The rotational speeds of the first rotating disk 6 and the second rotating disk 14 are the same, but the rotation directions are opposite. The concentration of the absorbent NaOH solution is 0.05 mol / L. A steel cylinder provides CO2 and N2, and the two are premixed to have a CO2 content of 2% (volume ratio) and then introduced into the high-gravity rotating bed. The gas flow rate is 12 m3 / h, and the liquid flow rate is 300 L / h. The absorption effect is shown in Table 1. Table 1 Effect of the Embodiment

Claims

1. A hypergravity bi-directional rotating bed device based on an end effect region, characterized in that: It includes a housing (2), a first turntable (6) rotatably arranged at the bottom of the housing (2), and a second turntable (14) rotatably arranged at the top of the housing (2). A plurality of first packings (7) are concentrically arranged on the first turntable (6), and a plurality of second packings (11) are concentrically arranged on the second turntable (14). The first packings (7) and the second packings (11) are both annular and concentrically distributed, and the first packings (7) and the second packings (11) are nested and alternately distributed at intervals. A liquid distributor (5) is arranged at the central position of the housing (2), and the liquid distributor (5) is used to spray liquid onto the innermost first packing (7) or second packing (11). A liquid phase outlet (1) is arranged at the bottom of the housing (2). A gas distributor (8) is arranged on the outer periphery of the outermost first packing (7) or second packing (11) in the housing (2). A gas inlet (9) distributed towards the gas distributor (8) is arranged on the side of the housing (2). An upflow hole (12) for the gas to flow up and be discharged from a gas outlet (13) arranged at the top of the housing (2) is arranged at the central position of the second turntable (14).

2. The supergravity bidirectional rotating bed device based on the end effect area according to claim 1, wherein: The housing (2), the first turntable (6), and the second turntable (14) are all circular and concentrically distributed.

3. The supergravity bi-directional rotating bed device based on the end effect region according to claim 1, characterized in that: Drive shafts extending to the outside of the housing (2) are arranged at the centers of the first turntable (6) and the second turntable (14), and the drive shafts are in transmission connection with a drive motor.

4. The supergravity bidirectional rotating bed device based on the end effect region according to claim 3, characterized in that: The drive shafts of the first turntable (6) and the second turntable (14) are in transmission connection with the same drive motor.

5. The supergravity bi-directional rotating bed device based on the end effect region according to claim 1, characterized in that: Both the first packing (7) and the second packing (11) are wire mesh packings.

6. The supergravity bi-directional rotating bed device based on the end effect region according to claim 5, characterized in that: The porosity of the first packing (7) and the second packing (11) is the same, and is 90 - 96%.

7. The supergravity bi-directional rotating bed device based on the end effect region according to claim 5, wherein: The porosity of the first packing (7) and the second packing (11) is different, and is 90 - 96%.

8. The supergravity bidirectional rotating bed device based on the end effect area according to claim 1, wherein: The thickness of the first packing (7) and the second packing (11) is the same, and is 5 - 30 mm.

9. The supergravity bi-directional rotating bed device based on an end effect area according to claim 1, characterized in that: The thickness of the first packing (7) and the second packing (11) is different, and is 5 - 30 mm.

10. A supergravity bidirectional rotating bed device based on an end effect area according to claim 1, characterized in that: A liquid pipeline (4) connected to the liquid distributor (5) is rotationally fitted at the center of the first turntable (6), and a U-shaped seal (3) is arranged between the liquid pipeline (4) and the first turntable (6).

11. The supergravity bidirectional rotating bed device based on an end effect area according to claim 1, wherein: The second turntable (14) is in clearance fit with the top wall of the housing (2), and an annular seal (10) is arranged between the top of the outer edge of the second turntable (14) and the top wall of the housing (2).

12. The supergravity bidirectional rotating bed device based on an end effect region according to claim 1, wherein: The gas distributor (8) is provided with uniformly or non-uniformly distributed air holes for the gas to pass through.

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