System and method for oil phase hydrogenation

Abstract

The invention relates to a system and a method for oil phase hydrogenation, and belongs to the technical field of liquid phase hydrogenation processes. The system comprises a hydrogen conveying unit, a raw oil conveying unit, a preheating unit, a hydrogen mixing unit, a hydrogenation reaction unit and a separation unit, the hydrogen mixing unit comprises a pre-reaction hydrogen mixing device, a double-layer pipe component is arranged in the hydrogen mixing unit, and the double-layer pipe component sequentially comprises an inner-layer pipe, a micro-nano porous membrane and an outer-layer pipe from inside to outside; and a plurality of through holes are formed in the outer-layer pipe and the inner-layer pipe in a penetrating manner. In addition, a discharge port of the hydrogenation reaction unit is communicated with a feed port of the preheating unit. By designing the pre-reaction hydrogen mixing device with a specific structure, hydrogen can be efficiently dispersed into microbubbles with uniform sizes, so that the hydrogenation reaction efficiency is effectively improved, and the energy consumption of a hydrogenation process is reduced; and the preheating unit is designed to be communicated with the hydrogenation reaction unit, and the hydrogenation product of the hydrogenation reaction unit can be utilized to preheat the raw oil, so that the energy consumption can be further reduced, and green low-carbon hydrogenation can be realized.

Description

Technical Field

[0001] This application relates to the field of oil phase hydrogenation process technology, and particularly to a system and method for oil phase hydrogenation. Background Technology

[0002] Due to the increasing extraction of low-quality crude oil, which contains a higher proportion of heavy components, the content of sulfur, nitrogen, aromatics, and gums in distillate oils from atmospheric and vacuum distillation and secondary processed oils from catalytic cracking and coking is also increasing. To maintain the sulfur and nitrogen content of the products at the required standards, the stringency of the hydrotreating process is constantly increasing. It often requires maintaining the reaction under high temperature, high pressure, and high hydrogen-to-oil ratio conditions to ensure deep desulfurization and denitrification, resulting in increasingly higher energy and material consumption in the hydrotreating process. Under the demand for energy conservation, emission reduction, and green, low-carbon transformation, the development of low-energy, green, and low-carbon oil-phase hydrotreating systems is of great significance.

[0003] Oil-phase hydrogenation is a typical gas-liquid multiphase reaction process. The efficiency of the hydrogenation reaction is related not only to the catalyst activity but also to the mass transfer rate between the hydrogen and oil phases. Based on the characteristics of micro / nano hydrogen bubbles—large specific surface area, high gas holdup, long residence time, and rapid dissolution—using a hydrogen mixing device to disperse hydrogen in the oil phase to generate microbubbles can effectively improve the mass transfer rate between the hydrogen and oil phases, thereby increasing the hydrogenation reaction efficiency. However, in the current field of industrial oil-phase hydrogenation, developing gas-liquid mixing equipment that uniformly disperses hydrogen in the oil phase as microbubbles is difficult. The generated microbubbles are large in size and unevenly distributed. Furthermore, the need for gas-fired heaters or circulating hydrogen compressors has not effectively reduced the energy consumption of the hydrogenation process, nor has it achieved green and low-carbon hydrogenation. Summary of the Invention

[0004] To address the aforementioned technical problems, embodiments of this application provide a system and method for oil-phase hydrogenation, which can efficiently form microbubbles of uniform size. Furthermore, through the comprehensive utilization of heat during the reaction process, it can effectively improve the hydrogen mixing effect and rate, increase the efficiency of the hydrogenation reaction, reduce the energy consumption of the hydrogenation process, and achieve low-energy, green, and low-carbon oil-phase hydrogenation.

[0005] In a first aspect, embodiments of this application provide a system for oil-phase hydrogenation, including a hydrogen delivery unit, a feedstock oil delivery unit, a preheating unit, a hydrogen mixing unit, a hydrogenation reaction unit, and a separation unit; The hydrogen mixing unit includes a pre-reaction hydrogen mixing device, a feedstock oil conveying unit, a preheating unit and the pre-reaction hydrogen mixing device connected in sequence, a hydrogen conveying unit connected to the pre-reaction hydrogen mixing device, the pre-reaction hydrogen mixing device, a hydrogenation reaction unit and a separation unit connected in sequence, and the outlet of the hydrogenation reaction unit connected to the inlet of the preheating unit. The pre-reaction hydrogen mixing device includes a shell with a first inlet and a mixed material outlet at opposite ends, and a second inlet on the side wall of the shell. Inside the shell, the first inlet sequentially connects to a first chamber, a second chamber, and a mixing chamber. The second chamber contains at least one double-layer tube component, and the second inlet connects to the second chamber. The double-layer tube component includes an outer tube, an inner tube nested within the outer tube, and a micro / nano porous membrane disposed between the outer and inner tubes. Multiple through holes are provided on both the outer and inner tubes. The first inlet connects to a hydrogen delivery unit, and the second inlet connects to a feedstock oil delivery unit; or, the first inlet connects to the feedstock oil delivery unit, and the second inlet connects to the hydrogen delivery unit.

[0006] In the above-mentioned technical solution, the system for oil-phase hydrogenation in this application incorporates a pre-reaction hydrogen mixing device within the hydrogen mixing unit. The structure of this device is designed to allow for several advantages. First, the double-layered tube structure combined with a micro / nano porous membrane enables the liquid phase to flow across both sides of the membrane, allowing the gas phase to pass through the membrane layer from the inside out or from the outside in, thus saturating and dissolving hydrogen rapidly and efficiently in the liquid feedstock. Excess hydrogen forms uniformly sized microbubbles that are evenly dispersed in the liquid phase. This eliminates the need for a hydrogen circulation compressor, effectively improving hydrogen utilization efficiency. Furthermore, the gas-liquid mixture entering the hydrogenation reaction unit does not require increased reaction pressure, further enhancing hydrogenation efficiency and reducing energy consumption in the hydrogenation process. Second, the design of a first chamber, a second chamber, and a mixing chamber within the pre-reaction hydrogen mixing device allows for flexible selection of either the gas or liquid phase at the first and second inlets. This high flexibility makes the entire system suitable for various operating conditions. In addition, by designing a preheating unit connected to the hydrogenation reaction unit, the hydrogenation products of the hydrogenation reaction unit can be used to preheat the feedstock oil, thereby eliminating the need for gas-fired heating furnaces and other devices, further reducing energy consumption, and facilitating green and low-carbon hydrogenation.

[0007] In some embodiments, an electric heating element is embedded within the outer and / or inner tubes. By incorporating the electric heating element, in the event of blockage in the micro / nanoporous membrane, the blockage within the pores can be melted or vaporized by heating the element, thus clearing the membrane pores and facilitating the long-term stable and efficient operation of the pre-reaction hydrogen mixing device.

[0008] In some embodiments, an electric heating element is embedded within the housing. By installing an electric heating element within the housing, directional heating of the gas-liquid mixture inside the hydrogen mixing device before the reaction can be achieved, thereby further improving the hydrogen mixing efficiency and thus the hydrogenation reaction efficiency. Furthermore, it can be combined with a preheating unit to achieve stepwise heating of the gas-liquid mixture, reducing the power consumption of a single processing unit.

[0009] In some embodiments, the electric heating element comprises, from the inside out, an insulating inner layer, a tungsten alloy conductive layer, and a protective outer layer. By designing a three-layer structure for the electric heating element, efficient directional heating of the liquid inside the tube or shell can be achieved, and a physical barrier can be effectively formed to prevent current leakage.

[0010] In some embodiments, the outer tube and the inner tube are each independently made of stainless steel or a stainless steel / ceramic composite material. Optionally, the shell is made of stainless steel. By controlling the materials of the outer tube, the inner tube, and the shell, high temperature and corrosion resistance can be achieved, which is beneficial for the long-term stable operation of the device.

[0011] In some embodiments, the housing includes an inlet section, an intermediate section, and an outlet section connected in sequence, and correspondingly forms a first chamber, a second chamber, and a mixing chamber. The diameters of the intermediate section, the inlet section, and the outlet section are equal; or, the diameters of the inlet section and the outlet section gradually decrease in the direction away from the intermediate section; or, the diameters of the inlet section and the outlet section gradually increase in the direction away from the intermediate section.

[0012] In the above technical solution, by designing the shape of the shell to control the dimensions of the first chamber, the second chamber, and the mixing chamber, and combining the gas and liquid phase materials introduced through the first and second inlets, different pre-reaction hydrogen mixing devices can be flexibly selected for different operating conditions. Specifically, a structure where the diameters of the inlet and outlet sections gradually increase away from the middle section is suitable for operating conditions with a liquid phase flow rate less than 0.5 m / s; a structure where the diameters of the inlet and outlet sections gradually decrease away from the middle section is suitable for operating conditions with a gas-liquid volume ratio greater than 0.5; and a structure where the diameters of the middle section, inlet section, and outlet section are equal is suitable for operating conditions with a gas-liquid volume ratio less than 0.5.

[0013] In some embodiments, the pre-reaction hydrogen mixing device further includes at least one fixed baffle that separates the first chamber and the second chamber, with multiple double-layered tube components arranged in an array on the fixed baffle. Designing the fixed baffle to array multiple double-layered tube components helps to further improve hydrogen mixing efficiency and device stability. In some implementations, the multiple double-layered pipe components are distributed on the fixed baffle in a concentric circle, equilateral triangle, or square pattern.

[0014] Optionally, the cross-sectional shape of the double-layer tube component is at least one of a circle, a triangle, or a polygon. Optionally, the through-holes on the double-layer tube member are in the shape of at least one of circles, triangles, or polygons. Optionally, the inner diameter or inscribed circle diameter of the through hole is 1mm to 10mm.

[0015] Optionally, the number of double-layer tube components distributed on the fixed baffle is 1 to 500. Optionally, the thickness of the micro / nanoporous membrane is 1 mm to 10 mm. Optionally, the average diameter of the micro-nanoporous pores on the micro-nanoporous membrane is 1 nm to 1000 μm. Optionally, the material of the micro / nanoporous membrane includes at least one of metal, glass, polymer material or ceramic.

[0016] In the above technical solution, by controlling the number and distribution of double-layer tube components, the shape of through holes, and the size and material of micro-nano porous membranes, it is beneficial to further improve the size uniformity of microbubbles and the hydrogen mixing efficiency.

[0017] In some embodiments, the hydrogenation reaction unit includes at least two catalyst beds, and the hydrogen mixing unit also includes an in-reactor hydrogen mixing device, which is disposed between every two adjacent catalyst beds. The in-reactor hydrogen mixing device includes at least one double-layer pipe component, and the double-layer pipe component is connected to the hydrogen delivery unit.

[0018] In the above technical solution, by further setting up a hydrogen mixing device inside the reactor, it is beneficial to ensure that hydrogen can be continuously and efficiently replenished in the form of microbubbles during the reaction process. At the same time, it can further eliminate the adverse effects of microbubbles agglomerating and growing during the tortuous movement and collision between closely packed catalyst particles, thus maximizing the hydrogenation reaction rate of feedstock in the hydrogenation reaction unit. The hydrogenation reaction rate can be increased without increasing the pressure, and the reaction pressure is reduced, which helps to further reduce the energy consumption of the hydrogenation process.

[0019] In some embodiments, the preheating unit includes a heat exchanger with a connected cold material inlet and a preheated material outlet, as well as a connected hot material inlet and a cold material outlet. The outlet of the feedstock oil conveying unit is connected to the cold material inlet of the heat exchanger, the liquid phase outlet of the hydrogenation reaction unit is connected to the hot material inlet of the heat exchanger, and the preheated material outlet of the heat exchanger is connected to the first or second inlet of the pre-reaction hydrogen mixing device.

[0020] In the above technical solution, by setting up a heat exchanger, the liquid-phase hydrogenation material in the hydrogenation reaction unit can exchange heat with the feed oil, so that the feed oil can reach the temperature required for the reaction before the reaction, thereby eliminating the need for a gas-fired heater. Through comprehensive utilization of heat in the hydrogenation reaction process, there is no carbon dioxide emission throughout the entire process, achieving green, low-carbon and low-energy consumption in the hydrogenation process.

[0021] In some embodiments, the preheating unit further includes a tubular electric heater, which is connected between the pre-reaction hydrogen mixing device and the heat exchanger. By further including the tubular electric heater, it is advantageous to ensure that the feedstock oil reaches the required reaction temperature at the reactor inlet. In some embodiments, the preheating unit further includes a circulating oil pump. The inlet of the circulating oil pump is connected to the liquid phase outlet of the hydrogenation reaction unit, and the outlet of the circulating oil pump is connected to the preheated material outlet of the heat exchanger, and also to the first or second inlet of the pre-reaction hydrogen mixing device. By setting up a circulating oil pump, the feedstock oil can be further mixed and preheated, which helps to ensure that the feedstock oil reaches the required reaction temperature at the reactor inlet, thereby further improving the efficiency of the hydrogenation reaction.

[0022] In some embodiments, the hydrogen mixing unit further includes a pre-heating hydrogen mixing device. The two inlets of the pre-heating hydrogen mixing device are respectively connected to the hydrogen delivery unit and the feedstock oil delivery unit, and the outlet of the pre-heating hydrogen mixing device is connected to the cold material inlet of the heat exchanger. By including a pre-heating hydrogen mixing device, the hydrogen mixing efficiency can be further improved.

[0023] In some embodiments, the separation unit includes a cold low-pressure separation device, an air-cooling device, and a three-phase separation device connected in sequence, as well as a gas-liquid separation device disposed within the hydrogenation reaction unit. The gas-liquid separation device is connected to the gas phase outlet and the liquid phase material outlet of the hydrogenation reaction unit; the inlet of the cold low-pressure separation device is connected to the cold material outlet of the heat exchanger; and the outlet of the cold low-pressure separation device and the gas phase outlet of the hydrogenation reaction unit are respectively connected to the inlet of the air-cooling device.

[0024] In the above technical solution, by setting up a gas-liquid separation device, a cold low-pressure separation device, an air-cooling device, and a three-phase separation device, it is beneficial to efficiently separate the gas-phase hydrogenated material and the heat-exchanged liquid-phase hydrogenated material.

[0025] Secondly, embodiments of this application provide a method for oil-phase hydrogenation, performed using the system of the first aspect of this application, the method comprising the following steps: The feedstock oil is sequentially transported to the preheating unit and the pre-reaction hydrogen mixing device through the feedstock oil conveying unit, and hydrogen is transported to the pre-reaction hydrogen mixing device through the hydrogen conveying unit to disperse the hydrogen into microbubbles and disperse them in the feedstock oil to form a gas-liquid mixture. The gas-liquid mixture is transported to the hydrogenation reaction unit, where it comes into contact with the hydrogenation catalyst to carry out the hydrogenation reaction. The hydrogenation products are then transported to the separation unit for separation to obtain hydrogenated oil products.

[0026] In the above technical solution, by employing the aforementioned system for oil-phase hydrogenation, the utilization rate of hydrogen can be significantly enhanced, the hydrogen mixing efficiency and hydrogenation reaction efficiency can be improved, and the reaction pressure and temperature can be reduced while maintaining the properties of the hydrogenation products unchanged. Under the same reaction temperature and pressure conditions, the sulfur and nitrogen content in the hydrogenation products can be further reduced. Simultaneously, since this process eliminates the need for a circulating hydrogen compressor, the energy consumption of the reaction process is significantly reduced. Furthermore, through the efficient utilization of heat during the reaction process, the traditional feedstock preheating furnace is eliminated, achieving zero carbon dioxide emissions throughout the entire process, making the hydrogenation process green and low-carbon.

[0027] In some embodiments, transporting the feedstock oil to the preheating unit and the pre-reaction hydrogenation mixing device via the feedstock oil conveying unit includes: exchanging heat between the feedstock oil and the hydrogenation liquid-phase product output from the hydrogenation reaction unit in a heat exchanger. By using the hydrogenation product to preheat the feedstock oil, the feedstock oil can reach the required reaction temperature before the reaction, thereby eliminating the need for a gas-fired heater. Through comprehensive utilization of heat during the hydrogenation reaction process, the entire process is free of carbon dioxide emissions, achieving a green, low-carbon, and low-energy-consumption hydrogenation process.

[0028] In some embodiments, after heat exchange, the feedstock oil is further heated by a tubular electric heater. This further heating by the tubular electric heater helps to ensure that the feedstock oil reaches the required reaction temperature at the reactor inlet. In some embodiments, the heating process further includes mixing and preheating the heated feedstock oil with a portion of the hydrogenation liquid phase product from the circulating oil pump 14. This further mixing and preheating of the feedstock oil helps to ensure that the feedstock oil reaches the required reaction temperature at the reactor inlet, thereby further improving the hydrogenation reaction efficiency. In some embodiments, before heat exchange, the process further includes: mixing the feedstock oil with a portion of hydrogen in a preheating hydrogen mixing device, and then conveying the mixed feedstock to a heat exchanger for heat exchange with the hydrogenated liquid phase product. In some embodiments, the hydrogenation catalyst has at least one shape selected from cloverleaf, four-leaf clover, spherical, toothed spherical, and cylindrical. By selecting the shape of the hydrogenation catalyst, the hydrogen mixing efficiency and the hydrogenation reaction efficiency can be further improved.

[0029] In some embodiments, the hydrogenation catalyst includes at least one of an oil-phase hydrogenation protection catalyst, a hydrorefining catalyst, and a hydrocracking catalyst. The oil-phase hydrogenation method provided in this application can be applied to the gas-liquid phase hydrogenation reaction processes of oil products such as gasoline, diesel, kerosene, wax oil, lubricating oil, residual oil, reformed oil, animal and vegetable oils, and direct and indirect coal liquefaction products, and appropriate hydrogenation catalysts can be selected accordingly.

[0030] In some embodiments, the catalyst bed formed by the hydrogenation catalyst loading contains multiple pore structures with an average diameter of 0.5 mm to 5 mm. By controlling the diameter of the pores formed by the catalyst loading, the aggregation and coalescence of microbubbles during the flow inside the catalyst bed can be avoided, thereby further improving the hydrogenation reaction efficiency.

[0031] In some embodiments, the microbubbles have a size of 10 nm to 1 mm. By employing the method of this application, smaller and more uniform microbubbles can be generated, which is beneficial for further improving the hydrogenation reaction rate.

[0032] In some embodiments, the feedstock includes at least one of gasoline, diesel, kerosene, wax oil, lubricating oil, residue oil, or reformed oil. The method in this application is applicable to the efficient hydrogenation of a variety of feedstocks.

[0033] In some embodiments, the hydrogenation reaction temperature is 100°C to 450°C, and the pressure is 1 MPa to 15 MPa. Using the hydrogenation process of this application, it is not necessary to increase the temperature and pressure of the hydrogenation reaction, allowing the hydrogenation reaction to proceed efficiently within a lower temperature and pressure range. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of a system for oil-phase hydrogenation provided in one embodiment of this application.

[0036] Figure 2 (a), (b), and (c) in the text are respectively Figure 1 The diagram shows a structural schematic of a pre-reaction hydrogen mixing device.

[0037] Figure 3 (a), (b), and (c) in the text are respectively Figure 1 The diagram shows a structural schematic of a pre-reaction hydrogen mixing device.

[0038] Figure 4 for Figure 2 or Figure 3 A schematic diagram of the internal double-layer tube structure of the hydrogen mixing device before the reaction.

[0039] Figure 5 (a), (b), (c), and (d) are respectively Figure 2 or Figure 3 A schematic diagram of the arrangement of the double-layer tube components inside the hydrogen mixing device before the reaction.

[0040] Explanation of reference numerals in the attached figures: 1-Hydrogen; 2-Hydrogen filtration device; 3-Hydrogen buffer tank; 4-Hydrogen compressor; 5-Feed oil; 6-Feed oil filtration device; 7-Feed oil pump; 8-Hydrogen mixing device before heating; 9-Hydrogen mixing device before reaction; 91-Shell; 92-Double-layer tube component; 921-Outer tube; 922-Inner tube; 923-Micro / nano porous membrane; 924-Through hole; 93-Fixed baffle; 94-First inlet; 942-First flow channel; 95-Second inlet; 952-The Two-channel system; 96-First chamber; 97-Second chamber; 98-Mixing chamber; 99-Mixed material outlet; 10-Hydrogenation reactor; 11-Catalyst bed; 12-Hydrogen mixing device inside the reactor; 13-Gas-liquid separation device; 14-Circulating oil pump; 15-Tube electric heater; 16-Heat exchanger; 17-Cold low-pressure separation device; 18-Air cooling device; 19-Three-phase separation device; 20-Demineralized water; 21-Sulfur-containing gas; 22-Sulfur-containing wastewater; 23-Hydrogenated oil. Detailed Implementation

[0041] The following detailed description, with appropriate reference to the accompanying drawings, specifically discloses embodiments of the system and method for oil-phase hydrogenation in this application. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided for the purpose of enabling those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0042] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for a specific parameter, it is also expected that ranges of 60~110 and 80~120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this application, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0043] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0044] Figure 1 Please refer to the structural schematic diagram of a system for oil-phase hydrogenation provided in one embodiment of this application. Figure 1 The system for oil-phase hydrogenation provided in the first aspect of this application includes: a hydrogen conveying unit, a feedstock oil conveying unit, a preheating unit, a hydrogen mixing unit, a hydrogenation reaction unit, and a separation unit. The hydrogen mixing unit includes a pre-reaction hydrogen mixing device 9. The feedstock oil conveying unit, the preheating unit, and the pre-reaction hydrogen mixing device 9 are connected in sequence. The hydrogen conveying unit is connected to the pre-reaction hydrogen mixing device. The pre-reaction hydrogen mixing device 9, the hydrogenation reaction unit, and the separation unit are connected in sequence. The outlet of the hydrogenation reaction unit is connected to the inlet of the preheating unit.

[0045] Figure 2 (a), (b), and (c) in the text are respectively Figure 1 A schematic diagram of one structure of the pre-reaction hydrogen mixing device 9 shown. Figure 3 (a), (b), and (c) in the text are respectively Figure 1 The diagram shows a structural schematic of the pre-reaction hydrogen mixing device 9. Please refer to... Figure 1 , Figure 2 and Figure 3 The pre-reaction hydrogen mixing device 9 includes a housing 91. The housing 91 has a first inlet 94 and a mixed material outlet 99 at opposite ends, and a second inlet 95 is provided on the side wall of the housing 91. Inside the housing 91, the first inlet 94 sequentially connects to a first chamber 96, a second chamber 97, and a mixing chamber 98. The second chamber 97 contains at least one double-layered pipe component 92, and the second inlet 95 connects to the second chamber 97.

[0046] Please see Figure 2 In some embodiments, the first inlet 94 is connected to a hydrogen conveying unit, and the second inlet 95 is connected to a feedstock oil conveying unit. That is, the first inlet 94 is a gas phase inlet, and the second inlet 95 is a liquid phase inlet. Correspondingly, the first chamber 96 is a gas phase chamber, and the second chamber 97 is a liquid phase chamber. This configuration is suitable for operating conditions where the liquid phase flow rate is 1 times or more than the gas phase flow rate. Please refer to [link / reference]. Figure 3 In some other embodiments, the first inlet 94 is connected to the raw material oil conveying unit, and the second inlet 95 is connected to the hydrogen conveying unit. That is, the first inlet 94 is the liquid phase inlet, and the second inlet 95 is the gas phase inlet. Correspondingly, the first chamber 96 is the liquid phase chamber and the second chamber 97 is the gas phase chamber. This is applicable to working conditions where the gas phase flow rate in the pipeline is 1 times or more than the liquid phase flow rate.

[0047] In some embodiments, the pre-reaction hydrogen mixing device 9 further includes a first flow channel 942 communicating between the first chamber 96 and the first inlet 94, and a second flow channel 952 communicating between the second chamber 97 and the second inlet 95.

[0048] Figure 4 yes Figure 2 or Figure 3 Please refer to the schematic diagram of the internal double-layer tube component 92 of the pre-reaction hydrogen mixing device 9. Figure 4 The double-layer tube component 92 includes an outer tube 921, an inner tube 922 nested inside the outer tube 921, and a micro / nano porous membrane 923 disposed between the outer tube 921 and the inner tube 922. Multiple through holes 924 are respectively provided on the outer tube 921 and the inner tube 922.

[0049] In this application, the size of the microbubbles formed in the hydrogen mixing device 9 before the reaction is 10nm~1000μm, for example, it can be 10nm, 50nm, 100nm, 200nm, 500nm, 1μm, 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 100μm, 200μm, 300μm, 400μm, 500μm, 600μm, 700μm, 800μm, 1000μm, etc.

[0050] In some embodiments, an electric heating element (not shown) is embedded in the outer tube 921 and / or the inner tube 922. Preferably, an electric heating element is embedded in both the outer tube 921 and the inner tube 922.

[0051] Understandably, the electric heating element is located in the outer tube 921 and / or the inner tube 922 at a position where there is no through hole 924. This application does not limit the type of electric heating element, as long as it can be heated by an external power source. As an example, the electric heating element is a tungsten alloy electric heating element. After connecting to an external power source, it can achieve directional heating of materials. Furthermore, in the case of micro / nanopore blockage, the rapid heating of the tungsten alloy can melt or vaporize the blockage within the pores, thus clearing the membrane pores.

[0052] In some embodiments, the electric heating element comprises, from the inside out, an insulating inner layer, a tungsten alloy conductive layer, and a protective outer layer, which facilitates the formation of a physical isolation barrier to prevent current leakage. Current is input from an external power source, enters the electric heating element through conductive leads, flows through the conductive layer, and returns to the circuit to form a loop. The heating temperature can be flexibly adjusted within the range of 0℃ to 1000℃. The insulating inner layer and the protective outer layer can be made of aluminum oxide.

[0053] Understandably, in the system of this application, the number of pre-reaction hydrogen mixing devices 9 can be two sets, with one set on standby and the function of high-temperature and high-pressure rinsing. If one set becomes blocked or the pressure drop increases during long-term use of the equipment, it can be switched to the other set. The blocked device can heat the membrane tube through an electric heating element to melt or vaporize the impurities adhering to the surface and pores of the membrane tube, and then clean it with high-temperature and high-pressure gas, thereby achieving cyclic use.

[0054] In some embodiments, the outer tube 921 and the inner tube 922 are each made of stainless steel or stainless steel / ceramic composite material.

[0055] In some embodiments, the cross-sectional shape of the double-layer tube member 92 is at least one of a circle, a triangle, or a polygon.

[0056] Furthermore, the outer diameter or the diameter of the circumscribed circle of the polygon of the double-layer tube component 92 is 10mm to 100mm, for example, it can be 10mm, 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm or 100mm, etc.

[0057] In some embodiments, the through hole 924 on the double-layer tube member 92 is at least one of a circle, a triangle, or a polygon. The inner diameter or inscribed circle diameter of the through hole 924 is 1mm to 10mm, for example, it can be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm, etc.

[0058] In some embodiments, the micro / nano porous membrane 923 is made of at least one of metal, glass, polymer, or ceramic. For example, it can be a combination of sintered metal porous membrane and glass porous membrane, a combination of sintered metal porous membrane and ceramic porous membrane, a combination of polymer porous membrane and ceramic porous membrane, a combination of ceramic porous membrane and multilayer wire mesh porous membrane, or a combination of metal porous membrane, ceramic porous membrane and multilayer wire mesh porous membrane, etc.

[0059] Furthermore, the thickness of the micro / nanoporous membrane 923 is 1mm to 10mm, for example, it can be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm, etc.; the length of the micro / nanoporous membrane 923 is 10mm to 2000mm, for example, it can be 10mm, 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, 200mm, 300mm, 400mm, 500mm, 600mm, 700mm, 800mm, 900mm, 1000mm, 1500mm, 2000mm, etc.

[0060] Furthermore, the average diameter of the micro-nanoporous pores on the micro-nanoporous membrane 923 is 1 nm to 1000 μm, for example, it can be 1 nm, 10 nm, 50 nm, 100 nm, 200 nm, 500 nm, 1 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 1000 μm, etc.

[0061] Furthermore, the micro-nano porous membrane 923 is tightly bonded to the outer tube 921 and the inner tube 922 on both sides.

[0062] Please continue reading Figure 2 and Figure 3 The pre-reaction hydrogen mixing device 9 also includes at least one fixed baffle 93, which separates the first chamber 96 and the second chamber 97. Multiple double-layer tube components 92 are arranged in an array on the fixed baffle 93.

[0063] Understandably, when the pre-reaction hydrogen mixing device 9 includes a fixed baffle 93, see [reference needed]. Figure 2 The mixing chamber 98 and the second chamber 97 are directly connected. The liquid phase enters the second chamber 97 through the second inlet 95, and the gas phase enters the double-layer tube component 92 through the first inlet 94 and forms microbubbles that diffuse into the liquid phase and enter the mixing chamber 98.

[0064] Figure 5 (a), (b), (c), and (d) are respectively Figure 2 or Figure 3 A schematic diagram of the arrangement of the double-layered tube components inside the pre-reaction hydrogen mixing unit. Please refer to [link / reference]. Figure 5 In some embodiments, the multiple double-layer pipe components 92 are distributed in a concentric circle pattern on the fixed baffle 93 (e.g., Figure 5 (a) ), equilateral triangle form (such as Figure 5 (b) or square (e.g.) Figure 5 (c) and (d)).

[0065] Furthermore, the number of double-layered tubular components 92 ranges from 1 to 500. For example, they can be distributed in concentric circles, with a quantity of 2; distributed in concentric circles, with a quantity of 200; distributed in concentric circles, with a quantity of 500; distributed in equilateral triangles, with a quantity of 3; distributed in equilateral triangles, with a quantity of 200; distributed in equilateral triangles, with a quantity of 500; distributed in squares, with a quantity of 4; distributed in squares, with a fractional quantity of 200; distributed in squares, with a quantity of 500, etc.

[0066] Please see Figure 3When the first inlet 94 is the liquid phase inlet and the second inlet 95 is the gas phase inlet, the pre-reaction hydrogen mixing device 9 includes two fixed baffles 93. One fixed baffle 93 separates the first chamber 96 and the second chamber 97, and the other fixed baffle 93 separates the second chamber 97 and the mixing chamber 98. The opposite ends of the double-layer tube component 92 are respectively fixed through a fixed baffle 93. The first chamber 96, the second chamber 97, and the mixing chamber 98 are connected through the double-layer tube component 92. The liquid phase enters the double-layer tube component 92 through the first inlet 94, and the gas phase enters the second chamber 97 through the second inlet 95 and diffuses into the double-layer tube component 92 to form microbubbles dispersed in the liquid phase. The gas phase is then transported to the mixing chamber 98 through the double-layer tube component 92.

[0067] Please continue reading Figure 2 and Figure 3 The housing 91 includes an inlet section (not shown), an intermediate section (not shown), and an outlet section (not shown) connected in sequence, which form a first chamber 96, a second chamber 97, and a mixing chamber 98.

[0068] In some embodiments, the diameters of the inlet and outlet sections gradually decrease away from the intermediate section; that is, the diameters of the first chamber 96 and the mixing chamber 98 gradually decrease away from the second chamber 97. Figure 2 (a) and Figure 3 (a) can be applied to working conditions where the gas-liquid volume ratio is greater than 0.5.

[0069] In other embodiments, the diameters of the inlet and outlet sections gradually increase away from the intermediate section; that is, the diameters of the first chamber 96 and the mixing chamber 98 gradually increase away from the second chamber 97. Figure 2 (b) and Figure 3 (b) applies to working conditions where the liquid flow rate is less than 0.5 m / s.

[0070] In other embodiments, the intermediate section, inlet section, and outlet section have equal diameters; that is, the first chamber 96, the second chamber 97, and the mixing chamber 98 have equal diameters. Figure 2 (c) and Figure 3 (c) can be applied to working conditions where the gas-liquid volume ratio is less than 0.5.

[0071] In some embodiments, an electric heating element is embedded within the housing 91. Understandably, the electric heating element within the housing 91 can have the same structure as the electric heating element within the double-layer tube component 92. Current is input from an external power source to the housing 91, enters the electric heating element through conductive leads, flows through the conductive layer, and returns to the circuit to form a loop. The electric heating element's geometric design (arc, spiral, swirling structure) allows control of the heat flow direction, achieving directional heating of the device's interior; the electric heating temperature of the housing 91 can be flexibly adjusted within the range of 0℃ to 1000℃.

[0072] Please continue reading Figure 1 In some embodiments, the hydrogenation reaction unit includes a hydrogenation reactor 10, which has at least two catalyst bed layers 11. The hydrogen mixing unit also includes an in-reactor hydrogen mixing device 12, which is disposed between every two adjacent catalyst bed layers 11. The in-reactor hydrogen mixing device 12 includes at least one double-layer pipe component, and the double-layer pipe component is connected to the hydrogen delivery unit.

[0073] Understandably, the double-layer tube component inside the hydrogen mixing device 12 in the reactor has the same structure as the double-layer tube component in the hydrogen mixing device 9 before the reaction.

[0074] Furthermore, a hydrogenation catalyst is provided in the catalyst bed 11, and the number of catalyst beds 11 can be 2 to 5.

[0075] Furthermore, the bottom of the hydrogenation reactor 10 is a gas-liquid mixture inlet connected to the pre-reaction hydrogen mixing device 9, and a hydrogen inlet is provided on the side, connected to the internal hydrogen mixing device 12.

[0076] The preheating unit includes a heat exchanger 16, which includes a cold material inlet (not labeled) and a preheated material outlet (not labeled) connected together, as well as a hot material inlet (not labeled) and a cold material outlet (not labeled) connected together. The outlet of the feed oil conveying unit is connected to the cold material inlet of the heat exchanger, the liquid phase outlet of the hydrogenation reactor 10 is connected to the hot material inlet of the heat exchanger 16, and the preheated material outlet of the heat exchanger 16 is connected to the first inlet or the second inlet of the pre-reaction hydrogen mixing device 9.

[0077] In some embodiments, the preheating unit further includes a tubular electric heater 15, which is connected between the pre-reaction hydrogen mixing device 9 and the heat exchanger 16. The tubular electric heater 15 may include an insulating inner layer, a tungsten alloy heating element, and a high-temperature resistant protective layer, enabling efficient and rapid heating of liquid materials.

[0078] In some embodiments, the preheating unit further includes a circulating oil pump 14, the inlet of which is connected to the liquid phase outlet of the hydrogenation reactor 10, the outlet of which is connected to the preheated material outlet of the heat exchanger 16, and the first or second inlet of the pre-reaction hydrogen mixing device 9.

[0079] In some embodiments, the hydrogen mixing unit further includes a pre-heating hydrogen mixing device 8, the two inlets of which are respectively connected to the hydrogen conveying unit and the raw material oil conveying unit, and the outlet of the pre-heating hydrogen mixing device 8 is connected to the cold material inlet of the heat exchanger.

[0080] Understandably, the hydrogen mixing device 8 before heating and the hydrogen mixing device 9 before reaction have the same structure in this application, and will not be described again here.

[0081] In some embodiments, the separation unit includes a cold low-pressure separation device 17, an air-cooling device 18, and a three-phase separation device 19 connected in sequence, and a gas-liquid separation device 13 disposed within the hydrogenation reactor 10, the gas-liquid separation device 13 being connected to the gas phase outlet and the liquid phase material outlet of the hydrogenation reactor 10. The inlet of the cold low-pressure separation device 17 is connected to the cold material outlet of the heat exchanger 16. The outlet of the cold low-pressure separation device 17 and the gas phase outlet of the hydrogenation reactor 10 are respectively connected to the inlet of the air-cooling device 18.

[0082] Understandably, the gas-liquid separation device 13 can separate the hydrogenated products into gas phases and output them from the gas phase outlet and the liquid phase outlet, respectively. As an example, the gas-liquid separation device 13 is a high-pressure separator that can separate the microbubbles in the hydrogenated oil phase from the oil phase at the top of the reactor after the microbubbles agglomerate into large bubbles.

[0083] In some embodiments, the hydrogen delivery unit includes a hydrogen filter 2, a hydrogen buffer tank 3, and a hydrogen compressor 4 connected in sequence, whereby hydrogen can be purified by the hydrogen filter 2 and pressurized by the hydrogen buffer tank 3 and the hydrogen compressor 4; the feedstock oil delivery unit includes a feedstock oil filter 6 and a feedstock oil pump 7 connected in sequence, whereby feedstock oil can be purified by the feedstock oil filter 6 and pressurized by the feedstock oil pump 7. The purified and pressurized hydrogen and feedstock oil can be efficiently mixed in the pre-reaction hydrogen mixing device 9.

[0084] Furthermore, the hydrogen filtration device 2 filters impurity particles with a particle size range of 10nm to 10μm, such as 1nm, 5nm, 10nm, 50nm, 100nm, 500nm, 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, or 10μm, etc.

[0085] Furthermore, the particle size range of the impurities filtered by the raw oil filtration device 6 is 1μm~50μm, for example, it can be 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 15μm, 20μm, 25μm or 50μm, etc.

[0086] Please see again Figure 1 The second aspect of this application also provides a method for oil-phase hydrogenation using the above-described system, comprising the following steps: The raw oil 5 is sequentially transported to the preheating unit and the pre-reaction hydrogen mixing device 9 through the raw oil conveying unit, and the hydrogen 1 is transported to the pre-reaction hydrogen mixing device 9 through the hydrogen conveying unit to disperse the hydrogen 1 into microbubbles and disperse them in the raw oil 5 to form a gas-liquid mixture. The gas-liquid mixture is transported to the hydrogenation reaction unit, where it comes into contact with the hydrogenation catalyst to carry out the hydrogenation reaction. The hydrogenation products are then transported to the separation unit for separation to obtain hydrogenated oil products.

[0087] In some embodiments, conveying the feedstock oil 5 to the preheating unit and the pre-reaction hydrogen mixing device 9 via the feedstock oil conveying unit includes: exchanging heat between the feedstock oil 5 and the hydrogenated liquid phase product output from the hydrogenation reactor 10 in the heat exchanger 16.

[0088] Furthermore, after heat exchange, the process also includes: heating the heat-exchanged raw material oil 5 into a tubular electric heater 15.

[0089] Furthermore, the heating process also includes: mixing and preheating the heated feedstock oil 5 with a portion of the hydrogenated liquid phase product from the circulating oil pump 14.

[0090] Furthermore, before heat exchange, the process includes: mixing the raw material oil 5 with a portion of hydrogen 1 in a preheating hydrogen mixing device 8, and then transporting the mixed raw material to a heat exchanger 16 for heat exchange with the hydrogenated liquid phase product.

[0091] In some embodiments, the oil-phase hydrogenation method provided in this application may include the following steps: Hydrogen gas 1 is passed through a hydrogen filter device 2 to obtain purified hydrogen. The purified hydrogen then enters a hydrogen buffer tank 3 and is pressurized by a hydrogen compressor 4. Raw material oil 5 is passed through a raw material oil filter device 6 to obtain purified raw material oil, which is then pressurized by a raw material pump 7. A portion of the pressurized hydrogen gas 1 and raw material oil 5 are first saturated with hydrogen in a preheating hydrogen mixing device 8 to obtain a hydrogen-oil mixture, which then enters a heat exchanger 16 to exchange heat with the high-temperature liquid-phase hydrogenated material output from the hydrogenation reactor 10. After heating, the raw material oil enters a tubular electric heater 15 for further heating, and then is further mixed and preheated with the high-temperature liquid-phase hydrogenation circulating oil output from the circulating oil pump 14. After preheating, the raw material oil 5 and purified hydrogen gas 1 are further intensified to dissolve hydrogen in a pre-reaction hydrogen mixing device 9. An appropriate amount of hydrogen is uniformly dispersed in the oil phase in the form of micro-nano bubbles and enters the hydrogenation reactor 10 in a pseudo-homogeneous state. During the reaction, a hydrogen mixing device 12 inside the reactor is used to enhance hydrogen supply to the catalyst bed 11 with cold hydrogen. The hydrogenation product undergoes gas-liquid separation at the top of the hydrogenation reactor 10 via a gas-liquid separator 13. The hydrogenated liquid phase product exchanges heat with the feed oil 5 and then enters a cold low-pressure separator 17. The hydrogenated gas phase product is combined with the non-condensable gas output from the top of the cold low-pressure separator 17 and then washed with demineralized water 20 to remove hydrogen sulfide. After water washing, it enters an air-cooling device 18 for cooling, which liquefies and separates the gaseous long-chain hydrocarbons. The air-cooled oil-water-gas three-phase mixture (containing sulfur-containing demineralized water, liquefied hydrocarbons, and non-condensable gas) enters a three-phase separator 19 for separation. The sulfur-containing gas 21 is sent to the desulfurization section, and the sulfur-containing wastewater 22 is sent to the wastewater treatment section. The liquefied oil phase and the oil phase at the bottom of the cold low-pressure separator 17 are combined to obtain the hydrogenated oil product 23.

[0092] It should be noted that this application does not limit the type of feedstock oil, and can be applied to any one or at least two combinations of gasoline, diesel, kerosene, wax oil, lubricating oil, residual oil, and reformed oil. Typical but non-limiting combinations include: combined hydrogenation of gasoline and diesel, combined hydrogenation of gasoline and reformed oil, combined hydrogenation of diesel and kerosene, combined hydrogenation of diesel and wax oil, and combined hydrogenation of wax oil and residual oil.

[0093] In some embodiments, the hydrogenation catalyst includes one or more combinations of oil-phase hydrogenation protection catalyst, hydrogenation refining catalyst, and hydrocracking catalyst, wherein typical but non-limiting combinations include: a combination of hydrogenation protection catalyst and hydrogenation refining catalyst, a combination of hydrogenation refining catalyst and hydrocracking catalyst, a combination of hydrogenation protection catalyst, hydrogenation refining catalyst and hydrocracking catalyst, etc.; the catalyst support structure includes one or more combinations of clover-shaped, four-leaf clover-shaped, spherical, toothed spherical, and cylindrical, wherein typical but non-limiting combinations include: a combination of clover and spherical, a combination of spherical and toothed spherical, a combination of spherical and cylindrical, a combination of spherical, toothed spherical and cylindrical, etc.

[0094] In some embodiments, the catalyst bed 11 formed by the hydrogenation catalyst loading contains multiple pore structures with an average diameter of 0.5 mm to 5 mm. For example, the pore diameters can be 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm. The diameter of the catalyst stacking pores is 1 to 10,000 times the diameter of the microbubbles, for example, the diameter of the catalyst stacking pores can be 1 mm, thereby preventing the microbubbles from accumulating and agglomerating during the flow process inside the catalyst bed 11.

[0095] In some embodiments, the size of the microbubbles is 10nm to 1000μm, for example, it can be 10nm, 50nm, 100nm, 200nm, 500nm, 1μm, 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 100μm, 200μm, 300μm, 400μm, 500μm, 600μm, 700μm, 800μm, 1000μm, etc.

[0096] In some embodiments, the reaction temperature of the hydrogenation reaction is 100°C to 450°C, for example, it can be 100°C, 150°C, 200°C, 250°C, 300°C, 320°C, 350°C, 380°C, 400°C or 450°C, etc., preferably 150°C to 380°C.

[0097] Furthermore, the reaction pressure of the hydrogenation reaction is 1 MPa to 15 MPa, for example, it can be 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, 12 MPa, 14 MPa or 15 MPa, preferably 2 MPa to 12 MPa.

[0098] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0099] Example 1 Please see Figures 1 to 5 This embodiment provides a system for oil-phase hydrogenation and a method for using the system, the method comprising the following steps: (1) Hydrogen 1 is passed through hydrogen filtration device 2 to remove solid particulate impurities with a particle size greater than 1 μm, resulting in filtered hydrogen. This filtered hydrogen is then pressurized by hydrogen buffer tank 3 and hydrogen compressor 4. Raw material oil 5 is passed through raw material oil filtration device 6, where the raw material oil is a mixture of straight-run wax oil and vacuum wax oil with a sulfur content of 15578 mg / kg. This filter removes solid particulate impurities with a particle size greater than 15 μm, resulting in filtered raw material oil. This filtered raw material oil is then pressurized by raw material oil pump 7. Under feeding conditions, the volume ratio of hydrogen 1 to raw material oil 5 is 10:1.

[0100] (2) Partially filtered and pressurized hydrogen 1 and filtered and pressurized feed oil 5 are mixed in a preheating hydrogen mixing device 8 to obtain an oil-gas mixture. The oil-gas mixture is a pseudo-homogeneous flow containing supersaturated dissolved hydrogen and uniformly sized hydrogen microbubbles with a diameter of 100 μm. The preheating hydrogen mixing device 8 is selected from... Figure 2 In the structure corresponding to (a), the first inlet 94 is the gas phase inlet, and the second inlet 95 is the liquid phase inlet. The cross-sectional shape of the double-layer tube component 92 is circular, with a diameter of 50 mm and a length of 1000 mm. It is distributed in an equilateral triangular array on the fixed baffle 93, with a quantity of 10. The micro-nano porous membrane 923 has an average micro-nano pore diameter of 100 μm. The through holes in the outer tube 921 and the inner tube 922 are circular, with an average pore diameter of 5 mm, and are made of stainless steel and ceramic composite. Tungsten alloy electric heating elements are embedded in both the outer tube 921 and the inner tube 922.

[0101] (3) The oil-gas mixture is passed through heat exchanger 16 to exchange heat with hydrogenated liquid phase products, and then enters tubular electric heater 15 for heating. After heating, it is mixed and preheated with part of the high-temperature hydrogenated liquid phase products output from circulating oil pump 14.

[0102] (4) The preheated oil-gas mixture and part of the filtered and pressurized hydrogen 1 are mixed in the pre-reaction hydrogen mixing device 9 to obtain a gas-liquid mixture. The structure of the pre-reaction hydrogen mixing device 9 is the same as that of the pre-heating hydrogen mixing device 8.

[0103] (5) The gas-liquid mixture enters the hydrogenation reactor 10, flows upward inside the hydrogenation reactor 10 and comes into contact with the catalyst bed 11 (hydrogenation catalyst). The reaction temperature is 355℃ and the reaction pressure is 6.0MPa. The catalyst bed 11 is set in 3 sections, and a hydrogen mixing device 12 is set between adjacent sections to supplement hydrogen between the beds. The hydrogenation catalyst is a wax oil hydrogenation refining catalyst with a toothed spherical shape. The hydrogenation reaction is carried out to obtain the hydrogenation product.

[0104] (6) The hydrogenation product is separated into gas and liquid phases by the gas-liquid separation device 13 at the top of the hydrogenation reactor 10. The hydrogenation liquid phase product is heated by the feed oil 5 and then enters the cold low-pressure separation device 17. The hydrogenation gas phase product is combined with the non-condensable gas at the top of the cold low-pressure separation device 17 and then washed by the demineralized water 20 before entering the air-cooling device 18. The air-cooled oil-water-gas three-phase mixture enters the three-phase separation device 19. The sulfur-containing gas 21 is sent to the desulfurization section, and the sulfur-containing wastewater 22 is sent to the wastewater treatment section. The liquefied oil phase and the oil phase at the bottom of the cold low-pressure separator are combined to obtain the hydrogenated oil product 23.

[0105] Example 2 This embodiment provides a system for oil phase hydrogenation and a method for using the system, which differs from Embodiment 1 only in that the number of double-layer tube components 92 is 10.

[0106] Example 3 This embodiment provides a system for oil-phase hydrogenation and a method for using the system. The method differs from that in Embodiment 1 only in that the average diameter of the micro-nanoporous membrane in the bilayer tube component 92 is 0.1 μm.

[0107] Example 4 This embodiment provides a system for oil phase hydrogenation and a method for using the system. The method differs from Embodiment 1 only in that the cross-sectional shape of the double-layer tube component 92 is triangular, and the through holes in the outer tube 921 and the inner tube 922 are triangular.

[0108] Example 5 This embodiment provides a system for oil-phase hydrogenation and a method for using the system. The only difference between this method and Embodiment 1 is that the structure of the pre-reaction hydrogen mixing device 9 and the pre-heating hydrogen mixing device 8 are adopted. Figure 3 In the structure corresponding to (a), the first feed port 94 is the liquid phase inlet and the second feed port 95 is the gas phase inlet.

[0109] Example 6 This embodiment provides a system for oil-phase hydrogenation and a method for using the system. The only difference between this method and Embodiment 1 is that tungsten alloy electric heating elements are not provided in the outer tube 921 and the inner tube 922.

[0110] Example 7 This embodiment provides a system for oil-phase hydrogenation and a method for using the system, the only difference from Embodiment 1 being that the tubular electric heater 15 is replaced with a gas-fired heater.

[0111] Comparative Example 1 This comparative example provides a system for oil-phase hydrogenation and a method for using the system, the only difference from Example 1 being that the double-layer tube component 92 does not contain a micro / nanoporous membrane 923.

[0112] Comparative Example 2 This comparative example provides a system for oil-phase hydrogenation and a method for using the system, the only difference from Example 1 being that a hydrogen mixing unit is not included.

[0113] Comparative Example 3 This comparative example provides a system for oil-phase hydrogenation and a method for using the system, the only difference from Example 1 being that only the hydrogen mixing device 12 is installed in the reactor.

[0114] Comparative Example 4 This comparative example provides a system for oil phase hydrogenation and a method for using the system. The method differs from Example 1 only in that: no hydrogen mixing unit is set up, and the hydrogenation reaction temperature in step (5) is adjusted to 370°C and the reaction pressure is adjusted to 12MPa.

[0115] Performance testing and results analysis (1) Sulfur content: The sulfur content of the hydrogenated oil products obtained in the examples and comparative examples was tested according to the standard GB / T17040-2019 Determination of Sulfur Content of Petroleum Products (Energy Dispersive X-ray Fluorescence Spectroscopy).

[0116] (2) Production process energy consumption: The energy consumption of the oil hydrogenation process is calculated according to the energy consumption calculation method of GB / T 30251-2013 Energy Consumption Limits of Refining Unit Products.

[0117] The reaction conditions and performance test results of the above embodiments and comparative examples are shown in Table 1.

[0118] Table 1 Hydrogenation reaction conditions and performance test results

[0119] As shown in Table 1, compared to Comparative Examples 1-4, the systems and methods in Examples 1-7 of this application can effectively reduce the sulfur content in hydrogenated oils under the same hydrogenation reaction temperature and pressure. Furthermore, while maintaining comparable product properties, they can effectively reduce reaction temperature and pressure, thereby lowering production process energy consumption. In Examples 1-7, the sulfur content in the hydrogenated oils is ≤125 mg / kg, and the production process energy consumption is ≤14 Etoa / t.

[0120] Based on Example 1 and Comparative Example 1, it can be seen that in Example 1, a micro / nano porous membrane 923 is provided inside the double-layer tube component 92. Compared to Comparative Example 1, the sulfur content in the hydrogenated oil in Example 1 is 125 mg / kg, and the production process energy consumption is 14 Etoa / t, while the sulfur content in the hydrogenated oil in Comparative Example 1 is 396 mg / kg, and the production process energy consumption is 21 Etoa / t. This indicates that by setting a micro-nano porous membrane 923 inside the double-layer tube component 92, it is beneficial to form smaller and more uniform microbubbles and improve the dispersion uniformity of microbubbles, thereby further improving the hydrogenation reaction efficiency, improving the desulfurization effect, and reducing the energy consumption of the production process to a certain extent.

[0121] Based on Example 1 and Comparative Example 2, it can be seen that Example 1 includes a hydrogen mixing unit. Compared to Comparative Example 2, which does not include a hydrogen mixing unit, the sulfur content of the hydrogenated oil in Example 1 is 125 mg / kg, and the production process energy consumption is 14 Etoa / t. In contrast, the sulfur content of the hydrogenated oil in Comparative Example 2 is 512 mg / kg, and the production process energy consumption is 23 Etoa / t. This demonstrates that by including a hydrogen mixing unit, the sulfur content of the hydrogenated oil and the production process energy consumption can be effectively reduced.

[0122] Based on Example 1 and Comparative Example 3, it can be seen that Comparative Example 3 only has an in-reactor hydrogen mixing device 12, but does not have a pre-heating hydrogen mixing device 8 and a pre-reaction hydrogen mixing device 9. In Example 1, the sulfur content of the hydrogenated oil is 125 mg / kg, and the production process energy consumption is 14 Etoa / t, while in Comparative Example 3, the sulfur content of the hydrogenated oil is 282 mg / kg, and the production process energy consumption is 19 Etoa / t. This shows that although the in-reactor hydrogen mixing device 12 can reduce the sulfur content of the hydrogenated oil and the production process energy consumption to a certain extent, the improvement effect is very limited.

[0123] Based on Examples 1 and 4, the reaction temperature in Example 1 was 355°C and the reaction pressure was 6 MPa. Compared to the reaction temperature of 370°C and the reaction pressure of 12 MPa in Comparative Example 4, the sulfur content of the hydrogenated oil in Example 1 was 125 mg / kg, and the production energy consumption was 14 Etoa / t. In contrast, the sulfur content of the feedstock oil after hydrogenation in Comparative Example 4 was 125 mg / kg, and the production energy consumption was 28 Etoa / t. This demonstrates that the embodiments of this application, under the condition of achieving the same hydrodesulfurization effect on the feedstock oil, can significantly reduce the hydrogenation reaction temperature, reaction pressure, and production energy consumption.

[0124] The embodiments described above are some, but not all, of the embodiments of this application. The detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

Claims

1. A system for oil-phase hydrogenation, characterized in that, It includes: a hydrogen conveying unit, a feedstock oil conveying unit, a preheating unit, a hydrogen mixing unit, a hydrogenation reaction unit, and a separation unit; The hydrogen mixing unit includes a pre-reaction hydrogen mixing device. The feedstock oil conveying unit, the preheating unit, and the pre-reaction hydrogen mixing device are connected in sequence. The hydrogen conveying unit is connected to the pre-reaction hydrogen mixing device. The pre-reaction hydrogen mixing device, the hydrogenation reaction unit, and the separation unit are connected in sequence. The outlet of the hydrogenation reaction unit is connected to the inlet of the preheating unit. The pre-reaction hydrogen mixing device includes a shell, with a first inlet and a mixed material outlet at opposite ends of the shell, and a second inlet on the side wall of the shell; inside the shell, the first inlet is sequentially connected to a first chamber, a second chamber, a mixing chamber and the mixed material outlet, and the second chamber is provided with at least one double-layer tube component, with the second inlet connected to the second chamber; The double-layer tube component includes an outer tube, an inner tube nested inside the outer tube, and a micro / nano porous membrane disposed between the outer tube and the inner tube. The outer tube and the inner tube are respectively provided with multiple through holes. The first inlet is connected to the hydrogen conveying unit, and the second inlet is connected to the feedstock oil conveying unit; or, the first inlet is connected to the feedstock oil conveying unit, and the second inlet is connected to the hydrogen conveying unit.

2. The system according to claim 1, characterized in that, An electric heating element is embedded in the outer tube and / or the inner tube; Optionally, an electric heating element is embedded within the housing; Optionally, the electric heating element comprises, from the inside out, an insulating inner layer, a tungsten alloy conductive layer, and a protective outer layer; Optionally, the outer tube and the inner tube are each made of stainless steel or stainless steel / ceramic composite material. Optionally, the housing is made of stainless steel.

3. The system according to claim 1, characterized in that, The housing includes an inlet section, a middle section, and an outlet section connected in sequence, which correspondingly form a first chamber, a second chamber, and a mixing chamber. The diameters of the middle section, the inlet section, and the outlet section are equal. Alternatively, the diameters of the inlet section and the outlet section gradually decrease in the direction away from the middle section; Alternatively, the diameters of the inlet section and the outlet section gradually increase in the direction away from the middle section.

4. The system according to claim 1, characterized in that, The pre-reaction hydrogen mixing device also includes at least one fixed baffle, which separates the first chamber and the second chamber, and multiple double-layer tube components are arranged in an array on the fixed baffle. Optionally, the distribution of the multiple double-layer tube components on the fixed baffle can be in the form of concentric circles, equilateral triangles, or squares; Optionally, the cross-sectional shape of the double-layer tube component is at least one of a circle, a triangle, or a polygon; Optionally, the through holes on the double-layer tube component are at least one of the following shapes: circular, triangular, or polygonal. Optionally, the inner diameter or inscribed circle diameter of the through hole is 1mm to 10mm; Optionally, the number of double-layer tube components distributed on the fixed baffle is 1 to 500; Optionally, the thickness of the micro / nanoporous membrane is 1 mm to 10 mm; Optionally, the average diameter of the micro-nanoporous pores on the micro-nanoporous membrane is 1 nm to 1000 μm; Optionally, the material of the micro / nanoporous membrane includes at least one of metal, glass, polymer material or ceramic.

5. The system according to claim 1, characterized in that, The hydrogenation reaction unit includes at least two catalyst beds, and the hydrogen mixing unit also includes an in-reactor hydrogen mixing device. The in-reactor hydrogen mixing device is disposed between every two adjacent catalyst beds. The in-reactor hydrogen mixing device includes at least one of the double-layer pipe components, and the double-layer pipe component is connected to the hydrogen delivery unit.

6. The system according to claim 1, characterized in that, The preheating unit includes a heat exchanger, which includes a cold material inlet and a preheated material outlet connected together, as well as a hot material inlet and a cold material outlet connected together. The outlet of the feed oil conveying unit is connected to the cold material inlet of the heat exchanger, the liquid phase outlet of the hydrogenation reaction unit is connected to the hot material inlet of the heat exchanger, and the preheated material outlet of the heat exchanger is connected to the first inlet or the second inlet of the pre-reaction hydrogen mixing device. Optionally, the preheating unit further includes a tubular electric heater, which is connected between the pre-reaction hydrogen mixing device and the heat exchanger; Optionally, the preheating unit further includes a circulating oil pump, the inlet of which is connected to the liquid phase outlet of the hydrogenation reaction unit, the outlet of which is connected to the preheated material outlet of the heat exchanger, and the first or second inlet of the pre-reaction hydrogen mixing device. Optionally, the hydrogen mixing unit further includes a pre-heating hydrogen mixing device, the two inlets of which are respectively connected to the hydrogen conveying unit and the feed oil conveying unit, and the outlet of which is connected to the cold material inlet of the heat exchanger.

7. The system according to claim 6, characterized in that, The separation unit includes a cold low-pressure separation device, an air-cooling device, and a three-phase separation device connected in sequence, as well as a gas-liquid separation device installed in the hydrogenation reaction unit. The gas-liquid separation device is connected to the gas phase outlet and the liquid phase material outlet of the hydrogenation reaction unit. The inlet of the cold low-pressure separation device is connected to the cold material outlet of the heat exchanger; the outlet of the cold low-pressure separation device and the gas phase outlet of the hydrogenation reaction unit are respectively connected to the inlet of the air-cooling device.

8. A method for oil-phase hydrogenation, employing the system as described in any one of claims 1 to 7, characterized in that, include: The feedstock oil is sequentially transported to the preheating unit and the pre-reaction hydrogen mixing device through the feedstock oil conveying unit, and hydrogen is transported to the pre-reaction hydrogen mixing device through the hydrogen conveying unit to disperse the hydrogen into microbubbles and disperse them in the feedstock oil to form a gas-liquid mixture. The gas-liquid mixture is transported to the hydrogenation reaction unit, where it comes into contact with the hydrogenation catalyst to carry out the hydrogenation reaction. The hydrogenation product is then transported to the separation unit for separation to obtain hydrogenated oil.

9. The method according to claim 8, characterized in that, The process of transporting feedstock oil through a feedstock oil conveying unit to a preheating unit and a pre-reaction hydrogen mixing unit includes: The feedstock oil and the hydrogenated liquid phase product output from the hydrogenation reaction unit exchange heat in a heat exchanger. Optionally, after heat exchange, the process further includes: heating the heat-exchanged raw oil in a tubular electric heater; Optionally, the heating process further includes: mixing and preheating the heated feedstock oil with a portion of the hydrogenated liquid phase product; Optionally, before heat exchange, the process further includes: mixing the feedstock oil with a portion of hydrogen in a preheating hydrogen mixing device, and then conveying the mixed feedstock to the heat exchanger to exchange heat with the hydrogenated liquid phase product.

10. The method according to claim 8, characterized in that, The hydrogenation catalyst has at least one shape selected from the following: clover-shaped, four-leaf clover-shaped, spherical, toothed spherical, and cylindrical. Optionally, the hydrogenation catalyst includes at least one of an oil-phase hydrogenation protection catalyst, a hydrorefining catalyst, and a hydrocracking catalyst; Optionally, the catalyst bed formed by the hydrogenation catalyst packing contains a plurality of pore structures, the average diameter of which is 0.5 mm to 5 mm; Optionally, the size of the microbubbles is 10 nm to 1 mm; Optionally, the feedstock oil includes at least one of gasoline, diesel, kerosene, wax oil, lubricating oil, residual oil, or reformed oil; Optionally, the temperature of the hydrogenation reaction is 100℃~450℃ and the pressure is 1MPa~15MPa.

Images