A variable diameter hydrogenation reaction system and its application

Abstract

The present invention discloses a variable diameter hydrogenation reaction system and its application. The variable diameter hydrogenation reaction system includes a hydrogenation reactor I and a hydrogenation reactor II; the hydrogenation reactor I is a variable diameter gas-liquid countercurrent hydrogenation reactor, comprising a gas deliquidation section, an upper reaction section, a countercurrent enhanced mass transfer section, a lower reaction section, and a liquid degassing section, which are sequentially connected from top to bottom; the diameters of the upper reaction section and the lower reaction section are both larger than the diameter of the countercurrent enhanced mass transfer section; a liquid feed port is provided between the gas deliquidation section and the upper reaction section; a gas feed port is provided between the lower reaction section and the liquid degassing section; a gas discharge port is provided above the gas deliquidation section; and a liquid discharge port is provided below the liquid degassing section; the hydrogenation reactor II includes at least one upflow tubular reactor; a feed port connected to the gas discharge port and the liquid discharge port of the hydrogenation reactor I is provided at the bottom of the upflow tubular reactor.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogenation, and in particular to a variable diameter hydrogenation reaction system and application thereof. Background Art

[0002] Catalytic hydrogenation technology is generally a process in which certain components containing unsaturated groups in the raw materials undergo a hydrogenation reaction to produce the desired product in an atmosphere of hydrogen and a catalyst. It has been widely used in fields such as oil refining, chemical industry, and biochemical industry. Fixed-bed catalytic hydrogenation processes mostly use traditional trickle-bed hydrogenation processes and gas-liquid-solid three-phase fixed-bed reactors. During the reaction process, the gas and liquid generally flow downward through the fixed catalyst bed to complete the catalytic hydrogenation reaction. In existing industrial trickle-bed hydrogenation processes, since the liquid passes through the catalyst bed in the form of a liquid film, it is easy to cause uneven liquid distribution, channeling and short-circuiting, which reduces the utilization rate of the catalyst and the reaction rate. Therefore, in order to ensure a more thorough hydrogenation reaction of the reactants, relatively harsh reaction conditions are generally required, such as a high hydrogen-to-liquid ratio, a long reaction residence time, a high temperature and hydrogen partial pressure, etc., which not only requires high equipment investment and energy consumption, but also has problems such as low reaction efficiency, low catalyst utilization, uneven reaction, and many side reactions.

[0003] To address these issues, various improved processes and reactors have emerged in the field of hydrogenation reactions. Patent CN109305882B proposes a method and apparatus for the continuous hydrogenation of glucose to produce sorbitol. This involves continuously adding glucose solution and hydrogen to a fixed-bed reactor and a slurry-bed reactor for sequential hydrogenation. While this process formally achieves continuous hydrogenation, it still suffers from issues such as low mass transfer reaction rates, long total material residence time, harsh reaction conditions, and high equipment investment and energy consumption.

[0004] Patent application CN116948701A proposes a bio-oil hydrogenation process, in which hydrogen enters a gas-liquid contact zone, partially flows upward through the gas-liquid contact zone, gas-liquid countercurrent zone, gas-liquid separation zone, and gas-phase reaction zone, and partially exchanges heat with liquid-phase material exiting the gas-liquid countercurrent zone and mixes with it before entering the liquid-phase reaction zone. The bio-oil feedstock enters the gas-liquid separation zone, partially converts to a gas phase, and enters the gas-phase reaction zone along with the gas-phase material from the gas-liquid countercurrent zone for hydrogenation, with the gas-phase reaction product flowing out of the top of the reactor. The liquid-phase material in the gas-liquid separation zone enters the gas-liquid countercurrent zone, where it reacts with hydrogen in a countercurrent fashion and enters the gas-liquid contact zone. The liquid-phase material then flows downward into the gas-liquid contact zone for liquid-phase hydrogenation, with the liquid-phase reaction product flowing out of the bottom of the reactor. This method has a limited scope of application and is applicable only to the reaction process and feedstocks described in the patented technology. Furthermore, conventional gas-liquid countercurrent reactors, when scaled up, often suffer from insufficient contact and low mass transfer efficiency.

[0005] Patent application CN112852477A proposes an upflow hydrogenation reactor, reactor system and catalytic hydrogenation process with multiple partitions. The upflow hydrogenation reactor includes a reactor shell, a support grid is provided at the bottom of the reactor shell, a pressurization zone is provided below the support grid, and a plurality of parallel upflow reaction zones are connected to the top of the support grid. Each upflow reaction zone is independent of each other and the flow area of ​​each upflow reaction zone is the same. The catalyst height and volume loaded in each upflow reaction zone are the same. An interception grid is provided on the top of each upflow reaction zone, and the outside of the interception grid is a gas-liquid separation zone. The reactor of this patented technology is provided with multiple independent reaction zones in order to prevent the problem of uneven radial distribution of materials. However, the reactor is not only complex in structure, but also does not solve the problems of uneven distribution of materials and uneven distribution of reaction heat, which is not conducive to heat conduction, especially for reactions with relatively large heat release.

[0006] In summary, existing hydrogenation processes and hydrogenation reactor types, whether using a combination of fixed-bed reactors and other types of reactors, or a fixed-bed co-current / counter-current or down-flow / up-flow reactor structure, are often designed to solve a problem in a certain reaction system and lack overall economic efficiency. As a result, most processes have problems such as high hydrogen-to-liquid ratio, harsh reaction conditions, low production efficiency, high energy consumption and investment. Summary of the Invention

[0007] To address the aforementioned technical issues and shortcomings in the art, the present invention provides a variable-diameter hydrogenation reaction system and its applications. This system couples a variable-diameter gas-liquid countercurrent hydrogenation reactor with an upflow tubular reactor to achieve segmented intensification of the entire hydrogenation reaction process. This significantly improves hydrogenation reaction efficiency and hydrogen utilization, reduces the hydrogen-to-liquid ratio, shortens reaction time, and reduces equipment consumption and investment. The system is suitable for hydrogenation reaction processes in industries such as oil refining, chemical engineering, biochemical engineering, pharmaceuticals, and food.

[0008] The "upflow" mentioned in the present invention refers to the flow of the reactant flow in the reactor from bottom to top; the "height-to-diameter ratio" generally refers to the ratio of the axial height of the reactor (or catalyst bed) to the cross-sectional diameter.

[0009] [1] A variable diameter hydrogenation reaction system comprising a hydrogenation reactor I and a hydrogenation reactor II;

[0010] The hydrogenation reactor I is a variable-diameter gas-liquid countercurrent hydrogenation reactor, comprising a gas deliquid section, an upper reaction section, a countercurrent enhanced mass transfer section, a lower reaction section, and a liquid degassing section, which are sequentially connected from top to bottom; the diameters of the upper reaction section and the lower reaction section are both larger than the diameter of the countercurrent enhanced mass transfer section; a liquid feed port is provided between the gas deliquid section and the upper reaction section; a gas feed port is provided between the lower reaction section and the liquid degassing section; a gas discharge port is provided above the gas deliquid section; and a liquid discharge port is provided below the liquid degassing section.

[0011] The hydrogenation reactor II includes at least one upflow tubular reactor; a feed port connected to the gas discharge port and the liquid discharge port of the hydrogenation reactor I is provided at the bottom of the upflow tubular reactor.

[0012] The liquid flows from top to bottom in the hydrogenation reactor 1, and the gas flows from bottom to top. The gas-liquid two phases undergo countercurrent contact mass transfer in the hydrogenation reactor 1.

[0013] In the variable-diameter hydrogenation reaction system, the gas-liquid separation section is used to remove liquid from the remaining hydrogen after the reaction is completed. This section can be equipped with a component capable of gas-liquid separation to perform gas-liquid separation. This component can be one or more of a baffle structure, a swirl / centrifugal structure, a packing, and a wire mesh structure.

[0014] The liquid degassing section of the variable-diameter hydrogenation reaction system is used to remove gases from the reaction liquid after the reaction is completed. The liquid degassing section can be configured with liquid level control and a specific liquid level to ensure sufficient residence time for liquid degassing. It may or may not be equipped with components with liquid degassing capabilities.

[0015] In the variable diameter hydrogenation reaction system, the height-to-diameter ratio of the countercurrent enhanced mass transfer section can be 2 to 30:1, preferably 3 to 10:1, such as 3.5:1, 4:1, 5:1, 8:1, etc.

[0016] In the variable diameter hydrogenation reaction system, the height-to-diameter ratios of the gas deliquid section, the upper reaction section, the lower reaction section, and the liquid degassing section may all be the same, or may not all be the same, or may all be different, and may be independently 0.5 to 5:1, preferably 1 to 3:1, such as 2:1, 2.5:1, etc. In the variable diameter hydrogenation reaction system, the height-to-diameter ratios of the gas deliquid section, the upper reaction section, the lower reaction section, and the liquid degassing section are preferably all the same.

[0017] In the variable diameter hydrogenation reaction system, the ratio of the material residence time of the upper reaction section to the countercurrent enhanced mass transfer section can be 1 to 100:10, preferably 1 to 2:2, such as 1:1.5.

[0018] In the variable diameter hydrogenation reaction system, the ratio of the material residence time of the lower reaction section to the countercurrent enhanced mass transfer section can be 1 to 100:10, preferably 1 to 2:2, such as 1:1.5.

[0019] In some embodiments, in the variable diameter hydrogenation reaction system, the upper reaction section, the countercurrent enhanced mass transfer section, and the lower reaction section are all loaded with catalysts.

[0020] In some embodiments, in the variable diameter hydrogenation reaction system, the porosity of the catalyst bed loaded in the upper reaction section and the lower reaction section is less than the porosity of the catalyst bed loaded in the countercurrent enhanced mass transfer section. The porosity of the catalyst bed loaded in the upper reaction section and the lower reaction section may be the same or different. The porosity of the catalyst bed loaded in the upper reaction section and the lower reaction section may be independently 10% to 50%, preferably 20% to 40%, such as 25%, 25.5%, 30%, 30.5%, 31.4%, 38.9%, 40%, etc. The porosity of the catalyst bed loaded in the countercurrent enhanced mass transfer section may be 30% to 90%, such as 52.5%, 60%, 62.5%, 70%, 80%, etc., preferably 50% to 80%. The porosity of the catalyst bed loaded in the upper reaction section and the lower reaction section is preferably the same.

[0021] In some embodiments, in the variable diameter hydrogenation reaction system, the catalyst particles loaded in the upper reaction section and the lower reaction section are smaller than the catalyst particles loaded in the countercurrent enhanced mass transfer section. The catalyst particles loaded in the upper reaction section and the lower reaction section may be the same or different. The catalyst particles loaded in the upper reaction section and the lower reaction section may be 0.3 to 3 mm, preferably 0.5 to 2 mm, such as 0.8 to 1.0 mm, 1.0 to 1.2 mm, 1.2 to 1.6 mm, 1.5 to 2 mm, etc. The catalyst particles loaded in the countercurrent enhanced mass transfer section may be 2 to 10 mm, preferably 3 to 6 mm, such as 2 to 3 mm, 2.8 to 3.8 mm, 3.2 to 3.6 mm, 4.0 to 4.6 mm, 4.5 to 5.5 mm, 6.0 to 6.6 mm, 7.5 to 8.5 mm, etc. The catalyst particles loaded in the upper reaction section and the lower reaction section are preferably the same size.

[0022] In the hydrogenation reactor I and the upflow tubular reactor, a catalyst having a hydrogenation function commonly used in the corresponding reaction, such as a copper-based, nickel-based, precious metal palladium-based, etc., can be selected according to different reactions. The best type of catalyst is generally selected according to the type of hydrogenation reaction; the hydrogenation catalyst is preferably a supported catalyst, wherein the catalyst carrier can be one or more of SiO2, Al2O3, SiO2-Al2O3, TiO2, activated carbon, MgO, molecular sieve, etc.; the shape of the hydrogenation catalyst can be one or more of spheres, bars, clover-shaped, toothed spheres, etc.; the hydrogenation catalyst can use commercially available products as needed, or it can be prepared according to conventional knowledge in the art.

[0023] In the variable diameter hydrogenation reaction system, heat can be taken or removed between the hydrogenation reactor I and the upflow tubular reactor according to the reaction requirements to achieve the best reaction effect.

[0024] In the variable diameter hydrogenation reaction system, the specific number of the upflow tubular reactors can be set according to actual needs, for example, 1 to 6.

[0025] In the variable diameter hydrogenation reaction system, a discharge port can be provided at the top of the upflow tubular reactor. The material flow pattern in the upflow tubular reactor can be from bottom to top.

[0026] In some embodiments, in the variable diameter hydrogenation reaction system, the hydrogenation reactor II may include multiple parallel upflow tubular reactors.

[0027] In the variable diameter hydrogenation reaction system, the upflow tubular reactor may have a height-to-diameter ratio of 2 to 15:1, preferably 3 to 8:1, such as 4:1, 5:1, 6:1, etc.

[0028] In the variable diameter hydrogenation reaction system, the upflow tubular reactor can be filled with a catalyst.

[0029] The voidage of the catalyst bed filled in the upflow tubular reactor may be 10% to 80%, for example, 38.5%, 42.5%, 52.5%, 58.2%, 60%, 70%, 70.3%, etc., preferably 30% to 60%.

[0030] The catalyst particles loaded in the upflow tubular reactor may have a size of 1.5 to 5 mm, preferably 2 to 4.5 mm, such as 2 to 2.2 mm, 2.4 to 2.6 mm, 3.5 to 4.5 mm, etc.

[0031] The variable diameter hydrogenation reaction system, the reaction feed of the upflow tubular reactor can be a liquid phase containing nano / micron dispersed hydrogen, and the liquid phase is formed by dissolving and / or dispersing part or all of the hydrogen discharged from the gas outlet of the hydrogenation reactor 1 in part or all of the reaction liquid discharged from the liquid outlet of the hydrogenation reactor 1 with or without additional hydrogen supplementation. What occurs in the upflow tubular reactor is an upflow liquid phase hydrogenation reaction, and the liquid phase hydrogenation refers to hydrogen being pre-dissolved and / or dispersed in the liquid reactant and then liquid-solid two-phase hydrogenation occurs. The remaining hydrogen of the hydrogenation reactor 1 can be used in whole or in part as a hydrogen source for the upflow tubular reactor. For reaction processes with large hydrogen consumption, a supplementary hydrogen pipeline can also be provided in the upflow tubular reactor to supplement the hydrogen required by the upflow tubular reactor.

[0032] The "dissolution and / or dispersion" described above can be achieved by using a mixing device. The mixing device generally includes one or more combinations of devices capable of liquid-liquid and / or gas-liquid mixing, such as a dissolved air pump, a mechanical stirring device, a colloid mill, a microporous plate nano / micro hydrogen dispersion assembly, a microbubble generator, a ceramic membrane nano / micro hydrogen dispersion assembly, and a microchannel mixer.

[0033] [2] Application of the variable diameter hydrogenation reaction system according to [1] in hydrogenation reaction.

[0034] The variable diameter hydrogenation reaction system of the present invention is applicable to various raw materials capable of undergoing hydrogenation reaction with hydrogen in the fields of petrochemical industry, medicine, food, etc., and can be crude oil and secondary processed oils such as crude oil, gasoline, kerosene, diesel, residual oil, heavy oil, wax oil, lubricating oil, deasphalted oil, biodiesel, animal oil or vegetable oil, coal tar, anthracene oil, etc., and can undergo reactions such as hydrogenation conversion of sulfur / nitrogen / oxygen / metal, hydrogenation saturation of olefins and diolefins, partial hydrogenation saturation of aromatics, and hydrocracking during the hydrogenation process. It can also be various raw materials containing carbon-carbon double bonds, carbon-carbon triple bonds, and organic functional groups in the chemical industry that can undergo hydrogenation reaction, such as reactions such as olefin hydrogenation, alkyne hydrogenation, aldehyde compound hydrogenation, ketone compound hydrogenation, ester compound hydrogenation, nitro compound hydrogenation, carbonyl compound hydrogenation, and nitrile compound hydrogenation.

[0035] [3] A hydrogenation method using the variable diameter hydrogenation reaction system described in [1].

[0036] In some embodiments, the hydrogenation method is as follows: the raw liquid enters the hydrogenation reactor I from the liquid feed port, and the hydrogen enters the hydrogenation reactor I from the gas feed port. The raw liquid and hydrogen undergo a countercurrent hydrogenation reaction in the hydrogenation reactor I. The remaining hydrogen after the reaction is completed leaves from the gas discharge port and partially or completely enters the upflow tubular reactor. After the reaction is completed, the reaction liquid leaves from the liquid discharge port and partially or completely enters the upflow tubular reactor; part or all of the remaining hydrogen discharged from the gas discharge port of the hydrogenation reactor I is dissolved and / or dispersed in part or all of the reaction liquid discharged from the liquid discharge port of the hydrogenation reactor I with or without additional hydrogen supplementation to form a liquid phase containing nano / micron dispersed hydrogen, and an upflow liquid phase hydrogenation reaction occurs in the upflow tubular reactor.

[0037] The gas-liquid ratio of the upflow tubular reactor can be adjusted according to the reaction requirements, hydrogen consumption and the need to control the conversion rate. In principle, the total hydrogen consumption is minimized under the premise of ensuring the best reaction effect. Among all the adjustment schemes, the preferred reaction process is to use the remaining hydrogen in the hydrogenation reactor I as the hydrogen source for the upflow tubular reactor to carry out the hydrogenation reaction.

[0038] In the hydrogenation method, the feed ratio of hydrogen to raw liquid in the hydrogenation reactor I can be 1 to 500 Nm 3 / h:1m 3 / h, preferably 5 to 100 Nm 3 / h:1m 3 / h.

[0039] In the hydrogenation method, the feed ratio of hydrogen to reaction liquid in the upflow tubular reactor can be 1 to 100 Nm 3 / h:1m 3 / h, preferably 2 to 20 Nm 3 / h:1m 3 / h.

[0040] The hydrogenation method may use hydrogen with a purity greater than 90 vol%, preferably using pure hydrogen greater than 99.9 vol%.

[0041] In the hydrogenation method, the reaction liquid after the reaction in the hydrogenation reactor I is completed can be partially recycled back to the hydrogenation reactor I as the first recycling material. Furthermore, the first recycling material can account for 0 to 90 wt% of the total fresh raw material liquid, preferably 5 wt% to 50 wt%.

[0042] In the hydrogenation process, the product of the upflow tubular reactor can be partially recycled back to the hydrogenation reactor I and / or the upflow tubular reactor as a second recycle material. Furthermore, the second recycle material can account for 5 wt% to 50 wt% of the total fresh feed solution, preferably 1 wt% to 20 wt%.

[0043] The process conditions of the hydrogenation reactor I and the upflow tubular reactor are generally determined by those skilled in the art based on the properties of the raw materials, the quality requirements of the final product, etc.

[0044] In some embodiments, the process conditions of the hydrogenation reactor I may include: a reaction temperature of room temperature to 500°C, a reaction pressure of 0.1 to 20 MPaG, a liquid hourly space velocity of 0.1 to 10 h -1 .

[0045] In some embodiments, the process conditions of the upflow tubular reactor may include: a reaction temperature of room temperature to 500°C, a reaction pressure of 0.1 to 20 MPaG, a liquid hourly space velocity of 1 to 20 h -1 .

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] In the present invention, the hydrogenation reactor I adopts a variable diameter countercurrent reactor structure, and the reaction gas-liquid mass transfer zone is divided into an upper reaction section, a countercurrent enhanced mass transfer section and a lower reaction section, wherein the upper reaction section / lower reaction section and the countercurrent enhanced mass transfer section are configured with variable diameters. This is mainly because as hydrogen and raw material substrates are continuously consumed during the reaction process, the gas-liquid ratio increases from the upper reaction section to the countercurrent enhanced mass transfer section and the lower reaction section, and the fresh raw material concentration decreases in sequence. That is, although the gas-liquid ratio in the upper reaction section is relatively low, the feed liquid is fresh raw material, the mass transfer driving force is large, and the reaction rate is faster; although the lower reaction section has a relatively low gas-liquid ratio, the feed liquid is fresh raw material, the mass transfer driving force is large, and the reaction rate is faster. The concentration of fresh raw materials is low, but the gas-liquid ratio is high, the liquid film mass transfer resistance is greatly reduced, and the reaction rate is also faster; while the gas-liquid ratio and raw material substrate concentration of the countercurrent enhanced mass transfer section are in an intermediate state, and the reaction rate is lower than that of the upper reaction section and the lower reaction section to a certain extent, which is the key to affecting the overall countercurrent reaction rate. Therefore, the present invention has set the countercurrent enhanced mass transfer section with a variable diameter, that is, by increasing the apparent flow velocity while maintaining the original gas-liquid ratio, so that the material reaches a highly turbulent state, thereby reducing the liquid film mass transfer resistance, increasing the mass transfer rate, and achieving the goal of strengthening the countercurrent mass transfer process.

[0048] In addition, each section is filled with catalysts of different void ratios and particle sizes, i.e., the upper reaction section / lower reaction section is filled with catalysts of low void ratio and small particle size, which can further improve the catalytic reaction mass transfer surface area, in order to realize the synergistic enhancement of reaction rate and catalyst in this region; the catalyst of high void ratio and large particle size is filled in the countercurrent enhanced mass transfer section, which is based on the high speed passing and high turbulence state of the material in this region, and the short contact time with the catalyst can achieve the ideal reaction effect, and the setting of high void ratio and large particle size is more conducive to the maintenance of material diffusion and turbulence state, thereby realizing the synergistic enhancement of reaction rate and catalyst in this region. In this way, the mass transfer reaction rate of the whole reaction process in hydrogenation reactor 1 has reached an overall higher state by segmented enhancement.

[0049] The hydrogenation reactor II adopts an upflow tubular reactor structure. On the one hand, considering that the concentration of the residual reaction substrate in the liquid material that has not completed the reaction of the hydrogenation reactor I is low, it is difficult to achieve the ideal reaction depth if any reactor structure such as fixed bed cocurrent or countercurrent is continued in series. Therefore, the process is set to adopt an upflow tubular reactor structure, which is to force the hydrogen and liquid materials to mix into a uniform "liquid phase material" and cause a plug flow liquid phase hydrogenation reaction in the upflow tubular reactor. This can greatly reduce or even eliminate the gas-liquid film interphase mass transfer resistance while reducing backmixing, thereby achieving the ideal reaction rate and reaction depth, which is particularly suitable for achieving a higher reaction depth when the reaction substrate concentration is low; on the other hand, based on the fact that there is still some residual hydrogen in the hydrogenation reactor I, it is more suitable as a hydrogen source for the upflow tubular reactor. During the reaction process, the hydrogen supply can be appropriately adjusted according to the reaction effect of each stage, hydrogen consumption and overall reaction depth, so as to maximize the synergistic enhancement of the hydrogenation reactor I and the upflow tubular reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a structural schematic diagram of a variable diameter hydrogenation reaction system of the present invention. DETAILED DESCRIPTION

[0051] The present invention will be further described below in conjunction with the accompanying drawings and specific examples. It should be understood that these examples are intended to illustrate the present invention and are not intended to limit the scope of the invention. The operating methods in the following examples where no specific conditions are specified are generally performed under conventional conditions or as recommended by the manufacturer.

[0052] See also Figure 1 , a variable diameter hydrogenation reaction system, including a first hydrogenation reaction zone and a second hydrogenation reaction zone.

[0053] The first hydrogenation reaction zone includes a hydrogenation reactor 1, which is a variable-diameter gas-liquid countercurrent hydrogenation reactor 5. It comprises a gas-liquid degassing section 8, an upper reaction section 9, a countercurrent enhanced mass transfer section 10, a lower reaction section 11, and a liquid degassing section 12, which are sequentially connected from top to bottom. The diameters of the upper reaction section 9 and the lower reaction section 11 are both larger than the diameter of the countercurrent enhanced mass transfer section 10. A liquid feed port is provided between the gas-liquid degassing section 8 and the upper reaction section 9; a gas feed port is provided between the lower reaction section 11 and the liquid degassing section 12; a gas discharge port is provided above the gas-liquid degassing section 8; and a liquid discharge port is provided below the liquid degassing section 12. The upper reaction section 9, the countercurrent enhanced mass transfer section 10, and the lower reaction section 11 are all loaded with catalyst. The porosity of the catalyst bed in the upper reaction section 9 and the lower reaction section 11 is lower than the porosity of the catalyst bed in the countercurrent enhanced mass transfer section 10. The catalyst particles filled in the upper reaction section 9 and the lower reaction section 11 are smaller in size than the catalyst particles filled in the countercurrent enhanced mass transfer section 10 .

[0054] The second hydrogenation reaction zone includes hydrogenation reactor II, which is one or more parallel upflow tubular reactors 18. Upflow tubular reactors 18 have feed ports at their bottoms that connect to the gas and liquid outlets of hydrogenation reactor I. Upflow tubular reactors 18 are loaded with catalyst.

[0055] A hydrogenation method, using the above Figure 1 The variable diameter hydrogenation reaction system shown includes:

[0056] In the first hydrogenation reaction zone, the liquid feed 1 and hydrogen 2 are respectively introduced into the liquid feed port and gas feed port of the hydrogenation reactor 1, and the liquid feed 1 is evenly distributed by the liquid feed distributor 6, enters the first catalyst bed 13 in the upper reaction zone 9, and undergoes a countercurrent hydrogenation reaction with the gas rising from the lower portion. The residual hydrogen after the reaction is removed by the gas deliquid section 8 and leaves the reactor, and enters the second hydrogenation reaction zone as the residual gas 3 of the first hydrogenation reaction zone; after the hydrogen 2 is evenly distributed by the hydrogen distributor 7, it enters the third catalyst bed 15 in the lower reaction zone 11 and undergoes a countercurrent hydrogenation reaction with the liquid descending from the upper portion. The reaction product leaves the reactor after being degassed by the liquid degassing section 12, and enters the second hydrogenation reaction zone as the reaction liquid product 4 of the first hydrogenation reaction zone; in the countercurrent enhanced mass transfer section 10, the liquid from the upper reaction zone 9 and the gas from the lower reaction zone 11 undergo enhanced mass transfer in the second catalyst bed 14, the gas product enters the upper reaction zone 9, and the liquid product enters the lower reaction zone 11;

[0057] In the second hydrogenation reaction zone, the residual gas 3 and the reaction liquid product 4 from the first hydrogenation reaction zone enter the mixer 16 for forced mixing, and the residual gas 3 is evenly dispersed in the reaction liquid product in the form of nanometers / micrometers to form a uniform liquid phase material as the feed 17 of the hydrogenation reactor II, which enters from the bottom of the hydrogenation reactor II, i.e., the upflow tubular reactor 18, and an upflow liquid phase hydrogenation reaction occurs through the fourth catalyst bed 19, and the reaction product 20 leaves from the top of the reactor.

[0058] The above-mentioned variable-diameter hydrogenation reaction system and hydrogenation method can be applied to phenol hydrogenation, dimethyl maleate hydrogenation, and biomass sugar (glucose) solution hydrogenation processes. The properties of the phenol feedstock are shown in Tables 1 and 2, and the properties of the phenol hydrogenation catalyst are shown in Table 3; the properties of the dimethyl maleate feedstock are shown in Table 4, and the properties of the dimethyl maleate hydrogenation catalyst are shown in Table 5; the properties of the biomass sugar (glucose) hydrogenation feedstock are shown in Table 6, and the properties of the biomass sugar (glucose) solution hydrogenation catalyst are shown in Table 7. All the above-mentioned raw materials are commercially available, and all hydrogenation catalysts are homemade.

[0059] Table 1 Properties of phenol raw materials

[0060] project index Remark Content / wt% ≥99.9 grade Premium products

[0061] Table 2 Properties of phenol hydrogenation solvent (water)

[0062] name index pH range (25℃) 5.0～7.5 Conductivity (25℃), mS / m≤ 0.50 Specific resistance (MΩ.cm, 25℃) ≥ 0.2 Oxidizable substances [in (O)], mg / L 0.40 Evaporation residue (105±2℃), mg / L≤ 2.0

[0063] Table 3 Phenol hydrogenation catalyst properties

[0064] Active Metals index Catalyst type Pd catalyst carrier <![CDATA[Al2O3]]> Active metal content, wt% 0.1～2.0

[0065] Table 4 Dimethyl Maleate Raw Materials

[0066] project index Traits Colorless transparent oily liquid Content, wt / % 99.5 <![CDATA[Density, g / m 3 > 1.124

[0067] Table 5 Properties of dimethyl maleate hydrogenation catalyst

[0068] project index Catalyst type Copper-based Active Metals copper Active metal content, wt% 10～50 catalyst carrier ZnO

[0069] Table 6 Biomass sugar (glucose) solution raw materials

[0070] project index Traits Colorless transparent liquid Concentration, mol / L 1.5

[0071] Table 7 Biomass sugar (glucose) solution hydrogenation catalyst properties

[0072] project Specifications shape spherical Active Metals nickel catalyst carrier <![CDATA[Al2O3]]> Nickel content, wt% 5～40

[0073] Comparative Example 1

[0074] A gas-liquid countercurrent fixed-bed hydrogenation reactor and an upflow tubular gas-liquid parallel flow reactor are connected in series, wherein the first hydrogenation reaction zone is provided with a gas-liquid countercurrent hydrogenation reactor I, and the height-to-diameter ratio of the hydrogenation reactor I is 2.5; the second hydrogenation reaction zone is provided with an upflow tubular gas-liquid parallel flow hydrogenation reactor II, and the height-to-diameter ratio of the hydrogenation reactor II is 2.5; the catalysts of the same specifications and sizes are filled in the hydrogenation reactors I and II, the catalyst porosity is 62.5%, and the catalyst particle size is

[0075] The device was used to investigate the hydrogenation of phenol, dimethyl maleate, and biomass sugar (glucose) under different conditions. First, the feedstock and hydrogen were thermostated to their respective inlet temperatures in hydrogenation reactor I, the first hydrogenation reaction zone. The feedstock and hydrogen then entered the catalyst bed from the top and bottom of hydrogenation reactor I to initiate hydrogenation. After forced mixing and thermostating, the top gas outlet and bottom liquid outlet entered the bottom of hydrogenation reactor II to continue the upflow hydrogenation reaction, exiting after completion.

[0076] The operating conditions of hydrogenation reactor I and hydrogenation reactor II are shown in Table 8, and the reaction results are shown in Table 9. The volume space velocity in Table 8 refers to the liquid hourly volume space velocity and is not further described below.

[0077] Comparative Example 2

[0078] A gas-liquid countercurrent fixed-bed hydrogenation reactor and an upflow tubular gas-liquid parallel flow reactor are connected in series. The first hydrogenation reaction zone is provided with a gas-liquid countercurrent hydrogenation reactor I, which is divided into three reaction zones: upper, middle and lower. The residence time ratio of the three reaction zones is 1:2:1. The height-to-diameter ratio of the upper and lower reaction zones is 2.0, and the height-to-diameter ratio of the middle reaction zone is 4.0. The second hydrogenation reaction zone is provided with two parallel gas-liquid parallel flow hydrogenation reactors II. The height-to-diameter ratio of the hydrogenation reactor II is 3.0. The catalysts of the same specifications and sizes are filled in the hydrogenation reactors I and II. The catalyst porosity is 62.5%, and the catalyst particle size is The hydrogenation reactor I and the hydrogenation reactor II are connected in series.

[0079] The device was used to investigate the hydrogenation of phenol, dimethyl maleate, and biomass sugar (glucose) under different conditions. The feedstock and hydrogen were first temperature-adjusted to the inlet temperature of hydrogenation reactor I, the first hydrogenation reaction zone. The feedstock and hydrogen were then introduced into hydrogenation reactor I from the top and bottom, respectively, where they underwent a gas-liquid countercurrent hydrogenation reaction inside hydrogenation reactor I, producing residual hydrogen and a reaction liquid. The reaction liquid was then temperature-adjusted and mixed with the residual hydrogen in a static mixer. The liquid then entered hydrogenation reactor II from the bottom for an upflow hydrogenation reaction, completing the reaction and exiting.

[0080] The operating conditions of hydrogenation reactor I and hydrogenation reactor II are shown in Table 8, and the reaction results are shown in Table 9.

[0081] Example 1

[0082] The system and method described in the specific embodiment of the present invention are used. The first hydrogenation reaction zone is provided with a hydrogenation reactor I. The first hydrogenation reactor I is a variable diameter gas-liquid countercurrent hydrogenation reactor structure, wherein the material residence time ratio of the upper reaction section to the countercurrent enhanced mass transfer section and the lower reaction section is 1:2:1, the height-to-diameter ratio of the upper reaction section and the lower reaction section is 2.0, the void ratio of the loaded catalyst is 31.4%, and the catalyst particle size is The height-to-diameter ratio of the countercurrent enhanced mass transfer section is 4.0, the void ratio of the loaded catalyst is 70%, and the catalyst particle size is The second hydrogenation reaction zone is equipped with a hydrogenation reactor II, which is a structure of two parallel upflow tubular liquid phase hydrogenation reactors. The height-to-diameter ratio of the hydrogenation reactor II is 5.0, the void ratio of the loaded catalyst is 38.5%, and the catalyst particle size is

[0083] This system was used to investigate the hydrogenation of phenol, dimethyl maleate, and biomass sugar (glucose) under different conditions. The feedstock was first temperature-adjusted to the inlet temperature of hydrogenation reactor I in the first hydrogenation reaction zone and then introduced from the top into gas-liquid countercurrent hydrogenation reactor I. Hydrogen, after temperature adjustment, was introduced from the bottom of gas-liquid countercurrent hydrogenation reactor I. A gas-liquid countercurrent hydrogenation reaction occurred within hydrogenation reactor I, yielding residual hydrogen and a reaction liquid. The reaction liquid and the residual hydrogen were then temperature-adjusted to the reaction temperature, uniformly mixed in a static mixer, and then introduced from the bottom of hydrogenation reactor II. The reaction proceeded from the bottom of the catalyst bed, where an upflow hydrogenation reaction occurred. The hydrogenation reaction was completed and then removed from the reactor.

[0084] The operating conditions of hydrogenation reactor I and hydrogenation reactor II are shown in Table 8, and the reaction results are shown in Table 9.

[0085] Example 2

[0086] The system and method described in the specific embodiment of the present invention are used. The process flow and reactor configuration are the same as in Example 1, except that: in hydrogenation reactor I, the residence time ratio of the upper reaction section, the lower reaction section, and the countercurrent enhanced mass transfer section is 1:1:1, the height-to-diameter ratio of the upper reaction section and the lower reaction section is 2.5, the void ratio of the loaded catalyst is 25.5%, and the catalyst particle size is The height-to-diameter ratio of the countercurrent enhanced mass transfer section is 3.5, the void ratio of the loaded catalyst is 52.5%, and the catalyst particle size is The hydrogenation reactor II is an upflow tubular liquid phase hydrogenation reactor structure. The height-to-diameter ratio of the hydrogenation reactor II is 4.0, the void ratio of the loaded catalyst is 42.5%, and the catalyst particle size is

[0087] The operating conditions of hydrogenation reactor I and hydrogenation reactor II are shown in Table 8, and the reaction results are shown in Table 9.

[0088] Example 3

[0089] The system and method of the present invention are used, and the process flow and reactor configuration are the same as those in Example 1, except that the residence time ratio of the upper reaction section, the lower reaction section, and the countercurrent enhanced mass transfer section is 1:1.5:1, the height-to-diameter ratio of the upper reaction section and the lower reaction section is 2.5, the void ratio of the loaded catalyst is 30.5%, and the catalyst particle size is The height-to-diameter ratio of the countercurrent enhanced mass transfer section is 3.5, the void ratio of the loaded catalyst is 62.5%, and the catalyst particle size is The hydrogenation reactor II is an upflow tubular liquid phase hydrogenation reactor structure. The height-to-diameter ratio of the hydrogenation reactor II is 4.0, the void ratio of the loaded catalyst is 58.2%, and the catalyst particle size is

[0090] The operating conditions of hydrogenation reactor I and hydrogenation reactor II are shown in Table 8, and the reaction results are shown in Table 9.

[0091] Example 4

[0092] The system and method described in the specific embodiment of the present invention are used. The process flow and reactor configuration are the same as in Example 1, except that the residence time ratio of the upper reaction section, the lower reaction section, and the countercurrent enhanced mass transfer section is 1:2:1, the height-to-diameter ratio of the upper reaction section and the lower reaction section is 3, the void ratio of the loaded catalyst is 38.9%, and the catalyst particle size is The height-to-diameter ratio of the countercurrent enhanced mass transfer section is 8, the void ratio of the loaded catalyst is 80%, and the catalyst particle size is The hydrogenation reactor II is an upflow tubular liquid phase hydrogenation reactor structure. The height-to-diameter ratio of the hydrogenation reactor II is 6.0, the void ratio of the loaded catalyst is 58.2%, and the catalyst particle size is

[0093] The operating conditions of hydrogenation reactor I and hydrogenation reactor II are shown in Table 8, and the reaction results are shown in Table 9.

[0094] Example 5

[0095] The system and method described in the specific embodiment of the present invention are used, and the process flow and reactor configuration are the same as in Example 2. The difference lies in the reaction conditions of hydrogenation reactor I and the type of inlet material mixer of hydrogenation reactor II. Here, the inlet material mixer of hydrogenation reactor II adopts a dissolved air pump.

[0096] The operating conditions are shown in Table 8, and the reaction results are shown in Table 9.

[0097] Table 8 Operating conditions of hydrogenation reactor I and hydrogenation reactor II

[0098]

[0099] Table 9 Reaction effect

[0100]

[0101] It can be seen from the effects of the various embodiments and comparative examples of the present invention that the hydrogenation reaction system and hydrogenation method of the present invention are adopted, the hydrogenation reactor I adopts a countercurrent variable diameter hydrogenation reactor, and each reaction stage in the countercurrent variable diameter hydrogenation reactor is coupled with a catalyst, which can effectively enhance various types of hydrogenation reactions; the hydrogenation reactor II adopts an upflow tubular liquid phase hydrogenation reactor, which can realize liquid phase hydrogenation reaction in plug flow mode, greatly reducing or even eliminating the gas-liquid film interphase mass transfer resistance while reducing back mixing, thereby achieving a higher reaction rate and reaction depth, and is particularly suitable for deep hydrogenation reaction when the content of the intended hydrogenation component in the raw material is low. Therefore, the present invention couples the variable diameter reactor I of the first hydrogenation reaction zone with the upflow tubular reactor I of the second hydrogenation reaction zone, and the residual hydrogen in the first hydrogenation reaction zone is used as the hydrogen source of the second hydrogenation reaction zone. While achieving segmented enhancement of the entire hydrogenation reaction process, it greatly improves hydrogen utilization, reduces hydrogen-liquid ratio, shortens reaction time, and reduces device consumption and investment.

[0102] In addition, it should be understood that after reading the above description of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A variable diameter hydrogenation reaction system, characterized in that: It includes a hydrogenation reactor I and a hydrogenation reactor II; The hydrogenation reactor I is a variable-diameter gas-liquid countercurrent hydrogenation reactor, comprising a gas deliquid section, an upper reaction section, a countercurrent enhanced mass transfer section, a lower reaction section, and a liquid degassing section, which are sequentially connected from top to bottom; the upper reaction section, the countercurrent enhanced mass transfer section, and the lower reaction section are all loaded with catalyst; the diameters of the upper reaction section and the lower reaction section are both larger than the diameter of the countercurrent enhanced mass transfer section; a liquid feed port is provided between the gas deliquid section and the upper reaction section; a gas feed port is provided between the lower reaction section and the liquid degassing section; a gas discharge port is provided above the gas deliquid section; and a liquid discharge port is provided below the liquid degassing section. The hydrogenation reactor II includes at least one upflow tubular reactor; a feed port connected to the gas discharge port and the liquid discharge port of the hydrogenation reactor I is provided at the bottom of the upflow tubular reactor.

2. The variable diameter hydrogenation reaction system according to claim 1, characterized in that: The height-to-diameter ratio of the countercurrent enhanced mass transfer section is 2 to 30:1; The height-to-diameter ratios of the gas-to-liquid degassing section, the upper reaction section, the lower reaction section, and the liquid-to-gassing section are all the same, or not all the same, or all different, and are independently 0.5 to 5:1; The ratio of the material residence time in the upper reaction section to the countercurrent enhanced mass transfer section is 1 to 100:10; The ratio of the material residence time in the lower reaction section to the countercurrent enhanced mass transfer section is 1 to 100:

10.

3. The variable diameter hydrogenation reaction system according to claim 2, characterized in that: The height-to-diameter ratio of the countercurrent enhanced mass transfer section is 3 to 10:1; The height-to-diameter ratios of the gas-to-liquid degassing section, the upper reaction section, the lower reaction section, and the liquid-to-gassing section are all the same, or not all the same, or all different, and are independently 1 to 3:1; The ratio of the material residence time in the upper reaction section and the countercurrent enhanced mass transfer section is 1 to 2:2; The ratio of the material residence time in the lower reaction section and the countercurrent enhanced mass transfer section is 1 to 2:

2.

4. The variable diameter hydrogenation reaction system according to claim 1, characterized in that: The void ratio of the catalyst bed filled in the upper reaction section and the lower reaction section is smaller than the void ratio of the catalyst bed filled in the countercurrent enhanced mass transfer section; The void ratios of the catalyst beds in the upper reaction section and the lower reaction section are the same or different; the void ratios of the catalyst beds in the upper reaction section and the lower reaction section are independently 10% to 50%; The void ratio of the catalyst bed filled in the countercurrent enhanced mass transfer section is 30% to 90%; The catalyst particles in the upper reaction section and the lower reaction section are smaller than the catalyst particles in the countercurrent mass transfer enhancement section. The catalyst particles in the upper reaction section and the lower reaction section are of the same or different sizes; the catalyst particles in the upper reaction section and the lower reaction section are independently 0.3 to 3 mm in size; The size of the catalyst particles filled in the countercurrent enhanced mass transfer section is 2 to 10 mm.

5. The variable diameter hydrogenation reaction system according to claim 4, characterized in that: The void ratios of the catalyst beds in the upper reaction section and the lower reaction section are independently 20% to 40%; The void ratio of the catalyst bed filled in the countercurrent enhanced mass transfer section is 50% to 80%; The catalyst particles in the upper and lower reaction sections are independently loaded with a size of 0.5 to 2 mm; The size of the catalyst particles filled in the countercurrent enhanced mass transfer section is 3 to 6 mm.

6. The variable diameter hydrogenation reaction system according to claim 1, characterized in that: The hydrogenation reactor II comprises a plurality of upflow tubular reactors connected in parallel.

7. The variable diameter hydrogenation reaction system according to claim 1, characterized in that: The upflow tubular reactor has a height-to-diameter ratio of 2 to 15:

1.

8. The variable diameter hydrogenation reaction system according to claim 7, characterized in that: The upflow tubular reactor has a height-to-diameter ratio of 3 to 8:

1.

9. The variable diameter hydrogenation reaction system according to claim 1, characterized in that: The upflow tubular reactor is filled with a catalyst; the voidage of the catalyst bed filled in the upflow tubular reactor is 10% to 80%; the size of the catalyst particles filled in the upflow tubular reactor is 1.5 to 5 mm; The reaction feed of the upflow tubular reactor is a liquid phase containing nano / micron dispersed hydrogen, and the liquid phase is formed by dissolving and / or dispersing part or all of the hydrogen discharged from the gas outlet of the hydrogenation reactor I with or without additional hydrogen supplementation in part or all of the reaction liquid discharged from the liquid outlet of the hydrogenation reactor I. An upflow liquid phase hydrogenation reaction occurs in the upflow tubular reactor, and the liquid phase hydrogenation means that hydrogen is pre-dissolved and / or dispersed in the liquid reactant and then liquid-solid two-phase hydrogenation occurs.

10. The variable diameter hydrogenation reaction system according to claim 9, characterized in that: The void ratio of the catalyst bed filled in the upflow tubular reactor is 30% to 60%; the size of the catalyst particles filled in the upflow tubular reactor is 2 to 4.5 mm.

11. Use of the variable diameter hydrogenation reaction system according to any one of claims 1 to 10 in hydrogenation reactions.

12. A hydrogenation method, characterized in that: The variable diameter hydrogenation reaction system according to any one of claims 1 to 10 is used.

13. The hydrogenation method according to claim 12, characterized in that The raw material liquid enters the hydrogenation reactor I from the liquid feed port, and the hydrogen enters the hydrogenation reactor I from the gas feed port. The raw material liquid and the hydrogen undergo a countercurrent hydrogenation reaction in the hydrogenation reactor I. The remaining hydrogen after the reaction is completed leaves from the gas discharge port and partially or completely enters the upflow tubular reactor. The reaction liquid after the reaction is completed leaves from the liquid discharge port and partially or completely enters the upflow tubular reactor; part or all of the remaining hydrogen discharged from the gas discharge port of the hydrogenation reactor I is dissolved and / or dispersed in part or all of the reaction liquid discharged from the liquid discharge port of the hydrogenation reactor I with or without additional hydrogen to form a liquid phase containing nano / micron dispersed hydrogen, and an upflow liquid phase hydrogenation reaction occurs in the upflow tubular reactor.

14. The hydrogenation method according to claim 13, characterized in that The feed ratio of hydrogen to raw liquid in hydrogenation reactor I is 1 to 500 Nm 3 / h:1m 3 / h; The feed ratio of hydrogen to reaction liquid in the upflow tubular reactor is 1 to 100 Nm 3 / h:1m 3 / h; The hydrogenation method uses hydrogen with a purity greater than 90 vol%; After the reaction in hydrogenation reactor I is completed, the reaction liquid portion is recycled back to hydrogenation reactor I as the first circulating material, and the first circulating material accounts for 0 to 90 wt% of the total fresh raw material liquid; The product portion of the upflow tubular reactor is recycled back to the hydrogenation reactor I and / or the upflow tubular reactor as a second circulating material, and the second circulating material accounts for 5 wt% to 50 wt% of the total fresh feed liquid; The process conditions of hydrogenation reactor I include: reaction temperature of room temperature to 500°C, reaction pressure of 0.1 to 20 MPaG, liquid hourly volume space velocity of 0.1 to 10 h -1 ; The process conditions of the upflow tubular reactor include: reaction temperature of room temperature to 500°C, reaction pressure of 0.1 to 20 MPaG, liquid hourly volume space velocity of 1 to 20 h -1 .

15. The hydrogenation method according to claim 14, characterized in that The feed ratio of hydrogen to raw liquid in hydrogenation reactor I is 5 to 100 Nm 3 / h:1m 3 / h; The feed ratio of hydrogen to reaction liquid in the upflow tubular reactor is 2 to 20 Nm 3 / h:1m 3 / h; The hydrogenation method uses more than 99.9 vol% pure hydrogen; The first circulating material accounts for 5wt% to 50wt% of the total fresh raw material liquid; The second circulating material accounts for 1 wt% to 20 wt% of the total fresh raw material liquid.

Images