A hydrogenation distributor and reactor

Abstract

A kind of hydrogenation of aldehyde reaction is used distributor and reactor, belong to the field of hydrogenation of aldehyde reaction in chemical production, including cylindrical shell, its top and bottom are provided with reaction gas discharge pipe and material outlet pipe respectively, the upper area in shell is provided with heat exchange tube bundle, the side wall of shell below heat exchange tube bundle is provided with liquid phase inlet pipe and gas phase input pipe, the one end in the shell of gas phase input pipe is connected with diffusion flow guide, the top end of diffusion flow guide is communicated with the bottom of steady flow reactor, the top of steady flow reactor is open, and is below liquid phase inlet pipe.This application sets up diffusion flow guide and steady flow reactor, not only can make gas phase and liquid phase fully dispersed and uniformly mixed, ensure the full reaction, more importantly, can effectively reduce the pressure drop of gas phase partial pressure, reduce the precipitation of catalyst, and ensure the consistency of gas-liquid phase speed, significantly improve the stability of feed and reaction.

Description

Technical Field

[0001] This invention relates to the hydroformylation reaction in chemical production, specifically a distributor and reactor for the hydroformylation reaction. Background Technology

[0002] In the chemical industry, hydroformylation is an important synthetic technique. It involves the reaction of olefins, hydrogen, and carbon monoxide in the presence of a catalyst to produce aldehydes, which have one more carbon atom than the starting olefin. These aldehydes are crucial raw materials for manufacturing fine chemicals such as detergents, plasticizers, and surfactants. However, the efficient execution of hydroformylation places stringent requirements on reactor design and operating conditions.

[0003] In upflow hydroformylation reactors, the flow pattern of reactants has a crucial impact on process control and product quality assurance. During the reaction, the flow of gaseous reactants is often unstable and prone to backmixing. This instability not only leads to fluctuations in the reaction rate but also affects product distribution and selectivity. Furthermore, backmixing of gaseous reactants can cause locally excessively high or low reactant concentrations in the reaction system, thereby triggering side reactions and catalyst deactivation, severely impacting process stability and product quality.

[0004] In existing conventional small-diameter upflow reactors, gas uniformity is often achieved using perforated discs or tubes with perforations on the top or bottom, along with connected inlet pipes. However, with increasingly demanding requirements for gas uniformity, higher-performance gas uniformity equipment is being developed to meet different needs.

[0005] For example, CN103100352A uses a cap-type gas collector and distributor to disperse the continuous gas phase into tiny bubbles to increase the gas-liquid phase area, which is suitable for reaction systems where the reaction rate is greatly affected by the mass transfer process.

[0006] CN101632911A discloses an upflow reactor structure suitable for oil hydrotreating processes, which incorporates multiple distributors, including an initial distributor and intermediate distributors. Each distributor group consists of a conical baffle and a sieve plate or a string of sieve plates. This structure achieves uniform distribution by adjusting the sieve aperture diameter to control the flow resistance.

[0007] However, existing structures of this type are mainly suitable for three-phase reaction systems packed with solid catalysts, and do not react with the catalyst before the gaseous reactants are fully distributed.

[0008] Unlike ordinary gas-liquid reactions, although hydroformylation reaction involves three phases, the catalyst is in the liquid phase rather than the solid phase. In this case, the liquid phase catalyst system needs to maintain a certain gas phase partial pressure; otherwise, the catalyst is very easy to precipitate when the gas and liquid phases are not well mixed.

[0009] Traditional upflow reactors require a relatively high height to achieve full flow development, and the height of the development section is proportional to the diameter. In regions where the flow is not fully developed, the consumption of gaseous reactants leads to a decrease in partial pressure, which can cause catalyst precipitation problems. Summary of the Invention

[0010] To address the problem of catalyst precipitation in conventional upflow reactors used in hydroformylation reactions due to the inherent characteristics of the reaction, this invention provides a distributor and reactor for hydroformylation reactions. This distributor, by incorporating a diffuser and a flow stabilizer, not only ensures thorough dispersion and uniform mixing of the gas and liquid phases, guaranteeing a complete reaction, but more importantly, it effectively reduces the pressure drop of the gas phase partial pressure, minimizing catalyst precipitation, and ensuring consistent gas-liquid phase velocities, significantly improving the stability of the feed and reaction.

[0011] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: a distributor for hydroformylation reaction, comprising a cylindrical shell, wherein a reaction gas discharge pipe and a material outlet pipe are respectively provided at the top and bottom of the shell, a heat exchange tube bundle is provided in the upper region of the shell, and a liquid phase inlet pipe and a gas phase input pipe are provided on the side wall of the shell below the heat exchange tube bundle. One end of the gas phase input pipe inside the shell is connected to a diffuser, the top of the diffuser is connected to the bottom of a steady flow reactor, and the top of the steady flow reactor is open and located below the liquid phase inlet pipe.

[0012] As another optimized scheme for the distributor used in the above-mentioned hydroformylation reaction, the steady-flow reactor includes several concentric cylinders arranged around the central axis of the shell, and an annular channel is formed between two adjacent concentric cylinders. Several partition plates are arranged in each annular channel, and these partition plates divide the annular channel into several reaction channels parallel to the axial direction of the shell.

[0013] As another optimization scheme for the distributor used in the above-mentioned hydroformylation reaction, the ratio of the maximum width to the height of each reaction channel is 1:10-20.

[0014] As another optimized scheme for the distributor used in the above-mentioned hydroformylation reaction, the partition plates are distributed along the radial direction of the annular channel, and the positions of the partition plates in two adjacent annular channels are staggered.

[0015] As another optimized solution for the distributor used in the above-mentioned hydroformylation reaction, multiple partition plates are also provided in the innermost cylinder of the concentric cylinder. One side of these partition plates is fixedly connected to the inner wall of the cylinder, and the other side converges at the center of the cylinder, dividing the inside of the cylinder into several reaction channels parallel to the axial direction of the shell.

[0016] As another optimized embodiment of the distributor for the above-mentioned hydroformylation reaction, the diffusion guide includes a conical diffusion shroud, with a connection part at the bottom of the shroud that communicates with the gas phase input pipe, and at least one spirally distributed guide vane inside the diffusion shroud, so that the gas phase is constrained by the guide vane and spirals upward and enters from the bottom of the steady flow reactor.

[0017] As another optimized option for the distributor used in the above-mentioned hydroformylation reaction, the height of the diffusion shroud is 1 / 6 to 1 / 2 of the shell radius, and the cone angle is 60 to 160°.

[0018] As another optimized embodiment of the distributor for the above-mentioned hydroformylation reaction, a central rod coinciding with the axis of the housing is provided at the center of the diffusion shroud. One side of the guide vane is fixed to the inner wall of the diffusion shroud, and the other side surrounds and is fixed to the outer wall of the central rod.

[0019] As another optimized embodiment of the distributor for the above-mentioned hydroformylation reaction, the liquid inlet pipe is connected to a liquid distributor at one end inside the housing. The liquid distributor includes a main liquid distribution pipe and several branch liquid distribution pipes distributed on both sides of the main liquid distribution pipe. One end of the main liquid distribution pipe is closed and the other end is connected to the liquid inlet pipe. One end of the branch liquid distribution pipe is connected to the main liquid distribution pipe and the other end is closed. Several liquid distribution holes are distributed on the lower surface of both the main liquid distribution pipe and the branch liquid distribution pipe.

[0020] A reactor for hydroformylation reaction, wherein the above-mentioned distributor is installed inside the reactor.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1) By setting up a diffuser and a steady-flow reactor, this invention not only enables the gas phase and liquid phase to be fully dispersed and uniformly mixed, ensuring sufficient contact and reaction between reactants, effectively improving the reaction rate and product selectivity, thereby improving reaction efficiency and product quality, but also effectively reduces the impact of gas and liquid phase flow instability, avoiding side reactions and catalyst deactivation caused by excessively high or low local concentrations. At the same time, it can also effectively reduce the pressure drop of gas phase partial pressure, reduce catalyst precipitation, and ensure the consistency of gas and liquid phase velocities, significantly improving the stability of feeding and reaction.

[0023] 2) The flow diffuser of this invention features spirally distributed guide vanes. Compared to conventional multi-layer perforated plates or baffles, this significantly increases the residence time of gaseous reactants in the backflow diffusion section through the spiral flow structure, and also generates a strong rotating airflow during the spiral ascent. This rotating airflow provides a unique stirring effect on the liquid phase, resulting in more uniform gas-liquid mixing and effectively avoiding localized uneven gas-liquid distribution. This greatly improves the efficiency of the hydroformylation reaction and the selectivity of the products. Simultaneously, this structure also has a self-cleaning function; the rotating airflow from the spiral vanes prevents reactants from depositing on the walls and structure of the feed section, reducing the risk of clogging and ensuring long-term stable operation of the reactor—a technical effect difficult to achieve in ordinary gas-liquid reactions.

[0024] 3) The steady-flow reactor of this invention adopts a multi-layer concentric cylindrical nested structure, and a partition plate is set in each layer of annular channel to divide it into several reaction channels. These reaction channels have a very large height-to-diameter ratio, and the fluid in each reaction channel can develop rapidly and fully. In the reaction channels, the contact between the gaseous reactants and the liquid catalyst system and the liquid reactants is more uniform, which can effectively ensure the gas phase partial pressure, greatly reduce the catalyst precipitation, and is more suitable for the hydroformylation reaction characteristics. At the same time, since the flow resistance of each small channel is consistent, the gas and liquid phase velocities at the outlet are basically consistent, which significantly improves the stability of the reactor feed and provides a strong guarantee for the efficient and stable hydroformylation reaction. The effect produced by this special structure goes far beyond simply extending the contact reaction time and can solve the key technical problems in the hydroformylation reaction. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 A bottom view of the liquid distributor's structure;

[0027] Figure 3 This is a schematic diagram of the diffuser.

[0028] Figure 4 A schematic cross-sectional view of the diffuser structure;

[0029] Figure 5 This is a three-dimensional structural diagram of a steady-flow reactor;

[0030] Figure 6 This is a schematic cross-sectional view of a steady-flow reactor.

[0031] Figure 7 This is a top view of the top of the steady-flow reactor;

[0032] Reference numerals: 1. Shell, 101. Gas phase inlet pipe, 102. Liquid phase inlet pipe, 103. Material outlet pipe, 104. Reactant gas outlet pipe, 2. Heat exchange tube bundle, 3. Liquid distributor, 301. Main liquid distribution pipe, 302. Branch liquid distribution pipe, 303. Liquid distribution hole, 4. Diffusion guide, 401. Diffusion hood, 402. Connecting part, 403. Guide vane, 5. Steady flow reactor, 501. Concentric cylinder, 502. Partition plate, 503. Reaction channel. Detailed Implementation

[0033] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. Parts not explained in the following embodiments of the present invention, such as other components of the hydroformylation reactor, the material, installation and specific structure of the heat exchange tube bundle, etc., are all considered to be prior art known or should be known by those skilled in the art.

[0034] Example 1

[0035] A distributor for a hydroformylation reaction, such as Figure 1 As shown, the reactor includes a cylindrical distributor housing 1, which, when placed, has its axis perpendicular to the horizontal plane, i.e., it adopts a vertical cylindrical structure. The top and bottom of the housing are respectively equipped with a reaction gas discharge pipe 104 for discharging excess gas phase and a material outlet pipe 103 for discharging reaction products. A heat exchange tube bundle 2 is arranged in the upper region inside the housing 1. The heat exchange tube bundle 2 consists of several heat exchange tubes, each with its axis parallel to the axis of the housing 1. Heat exchange channels are formed between the heat exchange tubes. Cooling liquid is introduced into the liquid inlet of the heat exchange tube bundle 2 and discharged from the liquid outlet, thereby allowing the heat exchange tube bundle 2 to absorb the heat released by the hydroformylation reaction in the reactor and control the temperature inside the reactor, maintaining it at the most favorable reaction temperature. The side wall of the housing 1 below the heat exchange tube bundle 2 is equipped with a liquid phase inlet pipe 102 for introducing liquid phase into the reactor and a gas phase inlet pipe 101 for introducing gas phase into the reactor. Generally, the liquid phase inlet pipe 102 and the gas phase inlet pipe 101 are located on both sides of the shell 1, and there is a certain height difference between them. This height difference constitutes the reaction zone of the hydroformylation reaction. The end of the gas phase inlet pipe 101 inside the shell 1 is connected to a diffuser 4. The top of the diffuser 4 is connected to the bottom of the steady flow reactor 5. The reaction gas phase first enters the diffuser 4 through the gas phase inlet pipe 101, and then rises along the diffuser 4 into the steady flow reactor 5. At this time, the top of the steady flow reactor 5 is open and located below the liquid phase inlet pipe 102, and at a certain distance from the liquid phase inlet pipe 102. After the liquid phase enters the shell 1 from the liquid phase inlet pipe 102, it falls and enters the steady flow reactor 5 through the opening at the top of the steady flow reactor 5, and comes into contact with the gas phase entering the steady flow reactor 5 from bottom to top to undergo the hydroformylation reaction.

[0036] In this embodiment, as Figure 1 As shown, one end of the liquid inlet pipe 102 inside the housing 1 is connected to a liquid distributor 3. The liquid distributor 3 includes a main liquid distribution pipe 301 and several branch liquid distribution pipes 302 distributed on both sides of the main liquid distribution pipe 301, such as... Figure 2 As shown, both the main liquid distribution pipe 301 and the branch liquid distribution pipes 302 are metal pipes and are at the same horizontal level. These branch liquid distribution pipes 302 have varying lengths to ensure that the end of each branch liquid distribution pipe 302 is as close as possible to the inner wall of the housing 1. The distribution of the branch liquid distribution pipes 302 within the housing 1 is as uniform as possible. One end of the main liquid distribution pipe 301 is closed, and the other end is connected to the liquid phase inlet pipe 102. The closed end of the main liquid distribution pipe 301 is generally fixed to the inner wall of the housing 1, but it can also be left unfixed. The length of the liquid distribution main pipe 301 is slightly shorter than the diameter of the shell 1. One end of the liquid distribution branch pipe 302 is connected to the liquid distribution main pipe 301, which is generally welded or integrally formed. The other end of the liquid distribution branch pipe 302 is a closed end. Several liquid distribution holes 303 are distributed on the lower surface of both the liquid distribution main pipe 301 and the liquid distribution branch pipe 302. The liquid distribution holes 302 are evenly distributed along the length of the liquid distribution main pipe 301 and the liquid distribution branch pipe 302. Each liquid distribution hole 302 is a conical hole, and the end with the smaller diameter of the conical hole is inside the pipe.

[0037] Example 2

[0038] This embodiment is an improvement on embodiment 1. Its main structure is the same as that of embodiment 1, but the improvement lies in: [The following is a more detailed description of the improvement.] Figure 5 , Figure 6 and Figure 7 As shown, the steady-flow reactor 5 includes several concentric cylinders 501 arranged around the central axis of the shell 1. The central axes of these concentric cylinders 501 are all on the same straight line as the central axis of the shell 1. The outermost cylinder, i.e., the cylinder with the largest diameter, has its outer side wall fixedly connected to the inner side wall of the shell 1. The tops and bottoms of all the concentric cylinders 501 are flush, i.e., they are of equal height. An annular channel is formed between two adjacent concentric cylinders 501. The width of the annular channel, i.e., the ratio of the radii of the two concentric cylinders 501, is generally [ratio missing]. 1.05-1.3:1, Several partition plates 502 are set in each annular channel. The two ends of the partition plates 502 are flush with the top and bottom of the concentric cylinders 501. In the same annular channel, the distance between two adjacent partition plates 502 is generally 1 / 10-20 of the diameter of the inner sidewall of the annular channel (that is, the inner and outer cylinders that constitute the annular channel, the cylinder with the smaller diameter is the inner sidewall of the annular channel). These partition plates 502 divide the annular channel into several reaction channels 503 parallel to the axis of the shell 1.

[0039] In this embodiment, the ratio of the maximum width to the height of each reaction channel 503 is 1:10-20;

[0040] In this embodiment, the partition plates 502 are distributed along the radial direction of the annular channel, and the positions of the partition plates 502 in two adjacent annular channels are staggered from each other. They can also be arranged without being staggered, but the preferred arrangement is that they are staggered from each other.

[0041] In this embodiment, multiple partition plates 502 are also provided in the innermost cylinder of the concentric cylinder 501. One side of these partition plates 502 is fixedly connected to the inner wall of the cylinder, and the other side converges at the center of the cylinder, dividing the inside of the cylinder into several reaction channels 503 parallel to the axial direction of the shell 1.

[0042] Example 3

[0043] This embodiment is an improved version based on embodiment 1. Its main structure is the same as that of embodiment 1, but the improvement lies in: [The following is a more detailed description of the improvement.] Figure 3 and Figure 4 As shown, the diffuser 4 includes a conical diffuser 401, which is a metal cone with a top that is larger than its bottom. The top is fixed to the inner wall of the shell 1 and communicates with the bottom of the steady flow reactor 5. A connecting part 402 communicating with the gas phase input pipe 101 is provided at the conical bottom of the diffuser 401. At least one spirally distributed guide vane 403 is provided in the conical inner cavity of the diffuser 401 so that the gas phase is constrained by the guide vane 403 and rises spirally and enters from the bottom of the steady flow reactor 5. The guide vane 403 is fixed to the inner wall of the diffuser 401, thereby dividing the interior of the diffuser 401 into several spiral channels. The bottom of these spiral channels communicates with the connecting part 402, which is a short metal pipe. The top of the spiral channels communicates with the bottom of the steady flow reactor 5, so that the gas phase enters the steady flow reactor 5 in a spiral shape and reacts with the liquid phase.

[0044] In this embodiment, the height of the diffuser 401 is 1 / 6 to 1 / 2 of the inner radius of the shell 1, and the cone angle is 60 to 160°.

[0045] In this embodiment, a central rod coinciding with the axis of the housing 1 is disposed at the center of the diffusion cover 401. Figure 3 and Figure 4 As not shown in the diagram, one side of the guide vane 403 is fixed to the inner wall of the diffuser 401, and the other side surrounds and is fixed to the outer wall of the central rod.

[0046] Example 4

[0047] A reactor for hydroformylation reaction, wherein the distributor for hydroformylation reaction described in Examples 1-3 is installed inside the reactor.

Claims

1. A distributor for hydroformylation reaction, comprising a cylindrical shell (1), wherein a reaction gas discharge pipe (104) and a material outlet pipe (103) are respectively provided at the top and bottom, a heat exchange tube bundle (2) is provided in the upper region of the shell (1), and a liquid phase inlet pipe (102) and a gas phase inlet pipe (101) are provided on the side wall of the shell (1) below the heat exchange tube bundle (2), characterized in that: The gas phase input pipe (101) is connected to a diffuser (4) at one end inside the shell (1). The top of the diffuser (4) is connected to the bottom of the steady flow reactor (5). The top of the steady flow reactor (5) is open and located below the liquid phase inlet pipe (102).

2. The distributor for a hydroformylation reaction according to claim 1, characterized in that: The steady-flow reactor (5) includes several concentric cylinders (501) arranged around the central axis of the shell (1). An annular channel is formed between two adjacent concentric cylinders (501). Several partition plates (502) are arranged in each annular channel. These partition plates (502) divide the annular channel into several reaction channels (503) parallel to the axial direction of the shell (1).

3. A distributor for a hydroformylation reaction according to claim 2, characterized in that: The ratio of the maximum width to the height of each of the aforementioned reaction channels (503) is 1:10-20.

4. A distributor for a hydroformylation reaction according to claim 2, characterized in that: The partition plates (502) are distributed along the radial direction of the annular channel, and the positions of the partition plates (502) in two adjacent annular channels are staggered.

5. A distributor for a hydroformylation reaction according to claim 2, characterized in that: In the concentric cylinder (501), there are also multiple partition plates (502) in the innermost cylinder. One side of these partition plates (502) is fixedly connected to the inner wall of the cylinder, and the other side converges at the center of the cylinder, dividing the inside of the cylinder into several reaction channels (503) parallel to the axial direction of the shell (1).

6. A distributor for a hydroformylation reaction according to claim 1, characterized in that: The diffuser (4) includes a conical diffuser shroud (401), and a connection part (402) communicating with the gas phase input pipe (101) is provided at the bottom of the diffuser (401). At least one spirally distributed guide vane (403) is provided inside the diffuser (401) so that the gas phase is constrained by the guide vane (403) and rises spirally and enters from the bottom of the steady flow reactor (5).

7. A distributor for a hydroformylation reaction according to claim 6, characterized in that: The height of the diffuser (401) is 1 / 6 to 1 / 2 of the radius of the shell (1), and the cone angle is 60 to 160°.

8. A distributor for a hydroformylation reaction according to claim 6, characterized in that: The diffuser (401) has a central rod that coincides with the axis of the housing (1) at its center. One side of the guide vane (403) is fixed to the inner wall of the diffuser (401), and the other side surrounds and is fixed to the outer wall of the central rod.

9. A distributor for a hydroformylation reaction according to claim 1, characterized in that: The liquid inlet pipe (102) is connected to a liquid distributor (3) at one end inside the housing (1). The liquid distributor (3) includes a main liquid distribution pipe (301) and several branch liquid distribution pipes (302) distributed on both sides of the main liquid distribution pipe (301). One end of the main liquid distribution pipe (301) is closed and the other end is connected to the liquid inlet pipe (102). One end of the branch liquid distribution pipe (302) is connected to the main liquid distribution pipe (301) and the other end is closed. Several liquid distribution holes (303) are distributed on the lower surface of the main liquid distribution pipe (301) and the branch liquid distribution pipe (302).

10. A reactor for a hydroformylation reaction, characterized in that: The reactor is equipped with a distributor as described in any one of claims 1-9.

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