Slurry bed reactor with novel spiral pipe

Abstract

The invention discloses a slurry bed reactor with a novel spiral pipe, comprising: a tower body which is vertically arranged and is a hollow cavity with closed bottom and top; the inner spiral pipe is vertically arranged and located in an inner cavity of the tower body, and the outer spiral pipe is vertically arranged and located in the inner cavity of the tower body and arranged on the periphery of the inner spiral pipe in a sleeving mode; the inner spiral pipe and the outer spiral pipe are used for enabling fluid in the tower body to generate spiral motion, changing the distribution of the fluid in the tower body and further reducing the fluid speed in the central area, and are also used for removing heat in the slurry bed reactor through the outer surfaces of the inner spiral pipe and the outer spiral pipe; according to the invention, the problem of chimney effect or short-circuit flow existing in the traditional slurry bed reactor is solved, in addition, the problem of low gas content in the area close to the wall surface of the slurry bed reactor is also solved, the gas phase is promoted to be uniformly distributed in the slurry bed reactor, and the purpose of strengthening the performance of the slurry bed reactor is achieved.

Description

Technical Field

[0001] The invention belongs to the field of slurry bed reactors, and in particular relates to a slurry bed reactor with a novel spiral tube. Background Art

[0002] Slurry bed reactors have been widely used in processes such as Fischer-Tropsch synthesis due to their simple structure, online catalyst addition, and low energy consumption. However, they also have some disadvantages, such as significant back-mixing and difficult temperature control, which hinder process intensification. In particular, during chemical reactions, uneven fluid distribution in the slurry bed reactor can lead to radial and axial temperature gradients. In the worst case, catalyst activity decreases, and the slurry bed reactor may even lose control. Therefore, internal components are installed within the slurry bed reactor to influence the phase distribution of the reactants by altering the reactor's fluid dynamics, thereby improving the reactor's performance and production capacity.

[0003] Slurry bed reactors with vertical tube internals are most commonly used in highly exothermic systems such as Fischer-Tropsch synthesis. This is because vertical tube internals can increase the phase holdup in the slurry bed reactor and increase the contact area between the multiple phases, thereby enhancing the performance of the slurry bed reactor. However, vertical tubes increase the liquid phase velocity in the central region of the slurry bed reactor, resulting in a negative chimney effect. Therefore, new internals have been developed to improve the fluid dynamics of slurry bed reactors, such as pin-fin tubes. These not only change the phase holdup and liquid flow rate in the slurry bed reactor, but also provide a larger heat exchange area and higher heat exchange coefficient than vertical tubes. Therefore, slurry bed reactors with pin-fin tubes have been favored by some scholars and engineers. However, the uneven arrangement of pin-fin tubes (two tubes are symmetrically removed) can lead to severe short-circuiting.

[0004] Internals offer significant advantages for process intensification in slurry bed reactors, but currently developed internals still have some drawbacks that limit their application in slurry bed reactors. In particular, the geometric shape and layout of the internals affect the distribution of phase holdup, phase velocity, turbulence, and interphase mass and heat transfer. Summary of the Invention

[0005] The purpose of the present invention is to provide a slurry bed reactor with a novel spiral tube to solve the problems of high flow velocity in the central area, uneven multiphase distribution, low multiphase contact efficiency, and poor temperature control effect in traditional slurry bed reactors.

[0006] The present invention adopts the following technical solution: A slurry bed reactor with a novel spiral tube, comprising:

[0007] The tower body is arranged vertically and is a hollow cavity with closed bottom and top;

[0008] The inner spiral tube is vertically arranged in the inner cavity of the tower.

[0009] The outer spiral tube is vertically arranged, located in the inner cavity of the tower body, and is sleeved on the outer periphery of the inner spiral tube;

[0010] The inner and outer spiral tubes are spirally arranged upward, with their lower ends extending out of the lower sidewall of the tower body to communicate with the outside world, and their upper ends extending out of the upper sidewall of the tower body to communicate with the outside world.

[0011] The inner and outer spiral tubes are used to make the fluid in the tower body produce spiral motion, change the distribution of the fluid in the tower body, and thus reduce the fluid velocity in the central area. They are also used to remove heat inside the slurry bed reactor through their outer surfaces.

[0012] The beneficial effects of the present invention are:

[0013] The present invention solves the chimney effect or short-circuit flow problems existing in conventional slurry bed reactors. Furthermore, the problem of low gas holdup near the wall of the slurry bed reactor is also solved, thereby promoting uniform distribution of the gas phase within the slurry bed reactor and achieving the purpose of enhancing the performance of the slurry bed reactor.

[0014] The present invention utilizes inner and outer spiral tubes to cause the fluid in the tower body to generate spiral motion, thereby changing the distribution of the fluid in the tower body, thereby reducing the flow rate of the fluid in the central area of ​​the slurry bed reactor. The spiral motion prolongs the contact time between the multiple phases and improves the mass transfer effect of the multiple phases in the slurry bed reactor.

[0015] The inner and outer spiral tubes of the present invention can efficiently remove heat from the inside of the slurry bed reactor when cooling water is passed through, thereby improving the temperature control effect of the slurry bed reactor;

[0016] The present invention utilizes the large outer surfaces of the inner and outer spiral tubes and the long heat exchange path to effectively remove heat from the slurry bed reactor, thereby improving the temperature control effect of the slurry bed reactor; increasing the contact area of ​​the multiphase in the slurry bed reactor, and enhancing the contact efficiency between the multiphase media;

[0017] The inner and outer spiral tubes of the present invention occupy a small space, which makes the developed slurry bed reactor miniaturized and can be used in process sites with limited space and complex geometric shapes.

[0018] The present invention utilizes inner and outer spiral tubes to change the distribution of fluid inside the slurry bed reactor, reduce the flow rate of fluid in the central region of the slurry bed reactor, thereby extending the contact time between the multiphases and improving the mass transfer effect between the multiphase media in the slurry bed reactor.

[0019] The present invention has high heat transfer efficiency, high multiphase contact efficiency, and structured flow field, thereby improving the mass transfer and heat transfer performance of the slurry bed;

[0020] The outer surfaces of the inner and outer spiral tubes of the present invention can be sprayed with porous materials or sintered metal fiber layers to form a micron-scale pore structure, providing anchor points for catalyst particles to prevent them from sliding. Alternatively, spiral corrugations can be machined on the tube walls to retain catalyst particles through turbulent vortexes, thereby carrying more catalyst particles and increasing the multiphase contact area, thereby enhancing the performance of the slurry bed reactor.

[0021] The flow field of the present invention exhibits a structured distribution, effectively improving the phase holdup and energy efficiency of the slurry bed reactor. The inner and outer spiral tubes can induce vortices in the fluid and decompose large-scale vortices into small-scale vortices, thereby strengthening the structured flow of the fluid inside the slurry bed reactor and improving the phase holdup of the slurry bed reactor. In addition, the small-scale vortex flow can further enhance the convective heat transfer of the fluid and the contact of multiple phases, thereby improving the energy efficiency of the slurry bed reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a cross-sectional view of the present invention;

[0023] Figure 2 This is a schematic structural diagram of the support adjustment rod of the present invention;

[0024] Figure 3 This is a support effect diagram of the support adjustment rod of the present invention;

[0025] Figure 4 This is a schematic diagram of the peripheral connections of the present invention.

[0026] Among them: 1. Tower body; 2. Inner spiral tube; 3. Outer spiral tube; 4. Support adjustment rod; 5. Support rod; 6. Adjustment rod; 7. Gas supply system; 8. Feed system; 9. Product processing system; 10. Data acquisition system; 11. Gas distributor; 12. Exhaust system. DETAILED DESCRIPTION

[0027] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. The "direction" in the present invention is based on the position of the present invention in the direction of the present invention. Figure 1 Description of the direction of the state.

[0029] The present invention discloses a slurry bed reactor with a novel spiral tube, such as Figure 1 As shown, it includes: a tower body 1, an inner spiral tube 2, and an outer spiral tube 3.

[0030] The tower body 1 is arranged vertically, and is a hollow cavity with a closed bottom and a closed top.

[0031] The inner spiral tube 2 is vertically arranged and located in the inner cavity of the tower body 1 . The outer spiral tube 3 is vertically arranged and located in the inner cavity of the tower body 1 and sleeved on the outer periphery of the inner spiral tube 2 .

[0032] Among them, the inner spiral tube 2 and the outer spiral tube 3 are spirally arranged upward, the lower ends of the inner spiral tube 2 and the outer spiral tube 3 are used to extend out of the lower side wall of the tower body 1 to communicate with the outside world, and the upper ends of the inner spiral tube 2 and the outer spiral tube 3 are used to extend out of the upper side wall of the tower body 1 to communicate with the outside world.

[0033] In one embodiment, the spiral axes of the inner spiral tube 2 and the outer spiral tube 3 coincide with the axis of the tower body 1 .

[0034] The inner spiral tube 2 and the outer spiral tube 3 are used to make the fluid in the tower body 1 produce spiral motion, thereby changing the distribution of the fluid in the tower body 1 and reducing the fluid velocity in the central area. They are also used to remove heat inside the slurry bed reactor through their outer surfaces.

[0035] In one embodiment, the lower ends of the inner spiral tube 2 and the outer spiral tube 3 are connected to an external cooling water source, and the upper ends of the inner spiral tube 2 and the outer spiral tube 3 are connected to an external drainage device. The cooling water entering the inner spiral tube 2 and the outer spiral tube 3 is used to exchange heat with the fluid inside the slurry bed reactor, thereby removing the reaction heat in the slurry bed reactor.

[0036] In one embodiment, the outer surfaces of the inner spiral tube 2 and the outer spiral tube 3 are sprayed with porous material or sintered metal fiber layer, which is used to provide anchoring points for catalyst particles in the slurry bed reactor.

[0037] In one embodiment, the outer surfaces of the inner spiral tube 2 and the outer spiral tube 3 are provided with spiral corrugations, which are used to retain catalyst particles through turbulent vortexes, increase the multiphase contact area, and thus enhance the performance of the slurry bed reactor.

[0038] In one embodiment, a plurality of adjustment holes are provided on the side wall of the tower body 1; the present invention also includes: a plurality of support adjustment rods 4, the plurality of support adjustment rods 4 are all horizontally arranged, the support adjustment rods 4 are obtained by integrally connecting the support rod 5 and the adjustment rod 6, the outer diameter of the adjustment rod 6 is larger than the outer diameter of the support rod 5, and the axes of the adjustment rod 6 and the support rod 5 do not coincide, the support rod 5 is used to pass through the adjustment hole and extend into the inner cavity of the tower body 1, and extend to the interlayer gap between the inner spiral tube 2 and the outer spiral tube 3, thereby supporting the inner spiral tube 2 and the outer spiral tube 3; the adjustment rod 6 is used to drive the support rod 5 to rotate after being twisted by an external force, and then adjust the height of the support rod 5 according to the position of the inner spiral tube 2 and the outer spiral tube 3 in the tower body 1, so as to support the inner spiral tube 2 and the outer spiral tube 3.

[0039] Preferably, the outer diameter of the support rod 5 is smaller than the gap between two adjacent layers of the inner spiral tube 2 or the outer spiral tube 3 .

[0040] Furthermore, if a layer of the inner spiral tube 2 or the outer spiral tube 3 directly faces the adjustment hole, thus interfering with the insertion of the support rod 5, the support rod 5 will be unable to extend to the lower side of the inner spiral tube 2 or the outer spiral tube 3 to support the inner spiral tube 2 or the outer spiral tube 3. However, there is no need to worry, as the present invention provides multiple support adjustment rods 4. The inability of a few support adjustment rods 4 to support the inner spiral tube 2 or the outer spiral tube 3 does not affect the supporting and fixing effect. Therefore, in this case, it is only necessary to extend the adjustment rod 6 into the adjustment hole and tighten it, thereby sealing the adjustment hole with the adjustment rod 6. In this case, the outer diameter of the adjustment rod 6 needs to be equal to the inner diameter of the adjustment hole.

[0041] In one embodiment, the present invention further comprises a top cover and a base. The top cover and the tower body 1 are connected by bolts, and the tower body 1 and the base are also connected by bolts.

[0042] A certain space is left between the inner spiral tube 2 and the outer spiral tube 3, so that the fluid can generate vortices of varying degrees, thereby optimizing the structure of the flow field inside the slurry bed reactor.

[0043] Cooling media of different temperatures can also flow into the inner spiral tube 2 and the outer spiral tube 3, thereby achieving the temperature control purpose of the slurry bed reactor.

[0044] In order to ensure that the inner spiral tube 2 and the outer spiral tube 3 are effectively fixed in the slurry bed reactor, a support adjustment rod 4 is provided. Figure 2 and Figure 3 As shown, it is only necessary to rotate the adjusting rod 6 to change the horizontal height of the support rod 5 in the tower body 1, so that the support rod 5 is tightly attached to the lower side of any layer of the inner spiral tube 2 and the outer spiral tube 3. By setting multiple supporting adjusting rods 4, the inner spiral tube 2 and the outer spiral tube 3 can be completely clamped to avoid vibration of the inner spiral tube 2 and the outer spiral tube 3.

[0045] If the support adjustment rod 4 is not provided, that is, the inner spiral tube 2 and the outer spiral tube 3 are not supported and fixed, then, first, the service life of the inner spiral tube 2 and the outer spiral tube 3 will be shortened because the inner spiral tube 2 and the outer spiral tube 3 will vibrate and produce metal fatigue. Secondly, the flow field in the tower body 1 will become unstable, thereby reducing the performance of the slurry bed. This is because the positions of the inner spiral tube 2 and the outer spiral tube 3 will undergo slight displacement during the vibration process, and the internal flow field structure of the slurry bed will be changed, thereby leading to uneven bubble distribution, particle sedimentation or increased backmixing, affecting the reaction efficiency of the multiphase medium; finally, the heat exchange medium in the inner spiral tube 2 and the outer spiral tube 3, such as cooling water, may leak. This is because the inner spiral tube 2 and the outer spiral tube 3 are connected to the inlet and outlet water systems. After the inner spiral tube 2 and the outer spiral tube 3 vibrate for a long time, it may cause cooling water leakage at a local location, causing safety or pollution problems of the slurry bed.

[0046] The slurry bed reactor of the present invention is connected with different systems, such as Figure 4 As shown, the bottom of the tower body 1 is connected to the air supply system 7, the bottom of the tower body 1 is also connected to the feeding system 8, the upper part of the tower body 1 is also connected to the product processing system 9, the top of the tower body 1 is connected to the exhaust system 12, and the middle part of the tower body 1 is connected to the data acquisition system 10.

[0047] The working mode of the slurry bed reactor of the present invention is:

[0048] The gas phase enters the slurry bed reactor through the gas supply system 7 and flows evenly into the tower body 1 under the action of the gas distributor 16. The material flows into the slurry bed reactor through the feed system 8, where it reacts with the gas phase to produce products. The products are recovered and processed by the product processing system 9. The excess gas phase is discharged from the slurry bed reactor through the exhaust system 12. The sensors of the data acquisition system 10 are evenly arranged throughout the slurry bed reactor. At the same time, to remove the heat generated by the multiphase reaction, the inner spiral tube 2 and the outer spiral tube 3 are connected to an external cooling water source.

[0049] The following experiments examined whether and how many spiral tubes should be installed within tower body 1. A tower body 1 with a diameter of 0.38 m and a height of 3 m was selected. Various parameters within tower body 1 were tested, including no spiral tubes, one spiral tube, and two spiral tubes (inner spiral tube 2 and outer spiral tube 3).

[0050] Table 1 Parameters of the spiral tube in the tower body of each comparative example

[0051]

[0052] Table 2 Gas holdup of each comparative example

[0053]

[0054] Note: Gas holdup refers to the gas content in the slurry bed reactor.

[0055] As can be seen from Table 2, within the superficial gas velocity range of 0.1-0.3 m / s, compared with the gas holdup of the slurry bed reactor without a spiral tube, the installation of one spiral tube can increase the gas holdup of the slurry bed reactor by 7%-25%, and the installation of two spiral tubes can increase the gas holdup of the slurry bed reactor by 10.4%-34%. It can be inferred that the installation of two spiral tubes is more conducive to improving the gas holdup of the slurry bed reactor and achieving the purpose of enhancing the performance of the slurry bed reactor.

[0056] Table 3 Turbulence characteristic length (Ll (m)) of each comparative example

[0057]

[0058] Note: The turbulent characteristic length is the scale of the turbulent vortex. (X, Y, Z) is a coordinate system established with the center of the bottom of the slurry bed reactor as the origin and the central axis of the slurry bed reactor as the Z axis.

[0059] It can be seen from Table 3 that under the condition of superficial gas velocity of 0.25 m / s, at Z = 0.38 m, setting one spiral tube and setting two spiral tubes have little effect on the turbulent characteristic length of the slurry bed reactor, which shows that the gas distributor 11 affects the distribution of the fluid but has little effect on the turbulent characteristic length.

[0060] However, at Y = 0 m and Z = 1.14 m, the turbulence characteristic length of the slurry bed reactor was significantly reduced with both one and two spiral tubes. The effect of two spiral tubes was particularly pronounced within the influence zone of the spiral tubes. At Z = 1.14 m, the installation of two spiral tubes reduced the turbulence characteristic length of the slurry bed to 0.05 m. This suggests that the increase in slurry bed gas holdup is due to the reduction in the turbulence characteristic length.

Claims

1. A slurry bed reactor with a novel spiral tube, characterized in that: include: The tower body (1) is arranged vertically and is a hollow cavity with a closed bottom and a closed top; The inner spiral tube (2) is vertically arranged and located in the inner cavity of the tower body (1). An outer spiral tube (3) is vertically arranged, located in the inner cavity of the tower body (1), and sleeved on the outer periphery of the inner spiral tube (2); The inner spiral tube (2) and the outer spiral tube (3) are arranged in a spiral upward direction, the lower ends of the inner spiral tube (2) and the outer spiral tube (3) are used to extend out of the lower side wall of the tower body (1) to communicate with the outside world, and the upper ends of the inner spiral tube (2) and the outer spiral tube (3) are used to extend out of the upper side wall of the tower body (1) to communicate with the outside world; The inner spiral tube (2) and the outer spiral tube (3) are used to cause the fluid in the tower body (1) to generate spiral motion, thereby changing the distribution of the fluid in the tower body (1) and thereby reducing the fluid velocity in the central area, and are also used to remove heat inside the slurry bed reactor through their outer surfaces.

2. A slurry bed reactor with a novel spiral tube according to claim 1, characterized in that: The lower ends of the inner spiral tube (2) and the outer spiral tube (3) are connected to an external cooling water source, and the upper ends of the inner spiral tube (2) and the outer spiral tube (3) are connected to an external drainage device. The cooling water entering the inner spiral tube (2) and the outer spiral tube (3) is used for heat exchange with the fluid inside the slurry bed reactor, thereby removing the reaction heat in the slurry bed reactor.

3. The slurry bed reactor with a novel spiral tube according to claim 1, characterized in that: The outer surfaces of the inner spiral tube (2) and the outer spiral tube (3) are sprayed with porous material or sintered metal fiber layers, and the porous material or sintered metal fiber layers are used to provide anchoring points for catalyst particles in a slurry bed reactor.

4. The slurry bed reactor with a novel spiral tube according to claim 1, characterized in that: The outer surfaces of the inner spiral tube (2) and the outer spiral tube (3) are provided with spiral corrugations, which are used to retain catalyst particles through turbulent vortexes, thereby increasing the multiphase contact area and enhancing the performance of the slurry bed reactor.

5. The slurry bed reactor with a novel spiral tube according to claim 1, characterized in that: A plurality of adjustment holes are provided on the side wall of the tower body (1); The invention also comprises: a plurality of support adjustment rods (4), all of which are arranged horizontally; the support adjustment rods (4) are obtained by integrally connecting a support rod (5) and an adjustment rod (6); the outer diameter of the adjustment rod (6) is larger than the outer diameter of the support rod (5), and the axes of the adjustment rod (6) and the support rod (5) do not overlap; the support rod (5) is used to pass through the adjustment hole and extend into the inner cavity of the tower body (1), and extend to the interlayer gap between the inner spiral tube (2) and the outer spiral tube (3), thereby supporting the inner spiral tube (2) and the outer spiral tube (3); the adjustment rod (6) is used to drive the support rod (5) to rotate after being twisted by an external force, thereby adjusting the height of the support rod (5) according to the position of the inner spiral tube (2) and the outer spiral tube (3) in the tower body (1), so as to support the inner spiral tube (2) and the outer spiral tube (3).

6. The slurry bed reactor with a novel spiral tube according to claim 1, characterized in that: The bottom of the tower body (1) is connected to the air supply system (7), the bottom of the tower body (1) is also connected to the feeding system (8), the upper part of the tower body (1) is also connected to the product processing system (9), the top of the tower body (1) is connected to the exhaust system (12), and the middle part of the tower body (1) is connected to the data acquisition system (10).

7. The slurry bed reactor with a novel spiral tube according to claim 1, characterized in that: The outer diameter of the regulating rod (6) is equal to the inner diameter of the regulating hole, and is used to extend the regulating rod (6) into the regulating hole to seal the regulating hole when a certain layer of the inner spiral tube (2) or the outer spiral tube (3) faces the regulating hole.

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