Hydrocarbon oil hydrogenation method and hydrogenation system

Abstract

The present invention relates to the field of petroleum refining and chemical industry, and discloses a method and system for hydrogenating hydrocarbon oil. The method includes the steps of: (1) carrying out a gas-phase desulfurization reaction of a hydrocarbon oil feedstock in a gas-phase hydrogenation reactor in the presence of hydrogen gas to obtain a gas-phase desulfurization reaction product; (2) boosting the pressure of the gas-phase desulfurization reaction product to obtain a boosted stream; and (3) sending the boosted stream to a liquid-phase hydrogenation reactor, and carrying out a liquid-phase hydrogenation reaction of the liquid-phase components in the boosted stream in the liquid-phase hydrogenation reactor to obtain a liquid-phase hydrogenation reaction product. The method and system according to the present invention can achieve the effect of high hydrogenation, and also simplify the overall process flow, reduce the severity of the reaction, and improve the efficiency of the chemical reaction.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of Chinese Patent Applications Nos. 202210008433.6, 202210008420.9 and 202210014492.4, filed on January 6, 2022, the contents of which are incorporated herein by reference.

[0002] [Technical field] The present invention relates to the fields of petroleum refining and chemical industry, and more particularly to a method and system for hydrogenating hydrocarbon oils. [Background technology]

[0003] Emissions from the combustion of sulfur and polycyclic aromatic hydrocarbons in diesel pollute the air environment on which humanity depends, leading countries to continuously accelerate the pace of improving diesel quality standards. China's National V diesel standard, implemented in 2017, stipulates that the sulfur content must not exceed 10 mg / kg. The National VI diesel quality standard proposed in 2019 requires polycyclic aromatic hydrocarbons to be ≤11%, while the National VIB standard, due to be implemented in 2023, requires polycyclic aromatic hydrocarbons to be ≤5%. China's demand for secondary processing feedstocks is also increasing day by day. Low-quality feedstocks, such as catalytic diesel, contain as much as 60% aromatic hydrocarbons, placing higher demands on catalytic activity. However, from the perspective of the reaction mechanisms of advanced desulfurization and advanced dearomatization, there are significant differences in the reaction environment requirements. In desulfurization reactions, the removal of low-molecular-weight sulfur is mainly achieved through the direct desulfurization route, i.e., hydrocracking desulfurization. Low-reactivity polymer sulfides are hydrocracking and desulfurizing via the hydrodesulfurization reaction pathway, where aromatic rings are hydrogenated and then hydrocracking and desulfurization are performed. Therefore, the upper part of the reactor is in a relatively low temperature and high hydrogen partial pressure environment, where the hydrocracking of low-molecular-weight sulfides (endothermic) and the hydrogenation of aromatic ring-containing compounds (exothermic) occur primarily. In the lower part of the reactor, heat and hydrogen sulfide accumulate, resulting in a high temperature and low hydrogen partial pressure reaction environment. While this reaction environment is conducive to further hydrocracking of hydrogenated polymer sulfides, it is severely limited by the thermodynamics of aromatic hydrocarbon hydrogenation and therefore highly unfavorable for further saturation of aromatic hydrocarbons. In particular, catalytic activity declines toward the end of the reaction, leaving no other option than to increase the temperature, further impacting the dearomatization effect. In addition to the various requirements for the reaction environment, competitive adsorption of aromatic hydrocarbons on the catalyst surface also inhibits deep desulfurization. Therefore, traditional hydrogenation technologies struggle to balance the two requirements of ultra-deep desulfurization and efficient saturation of aromatic hydrocarbons. This calls for an upgrade of diesel cleaning technology, both of which are necessary and urgent.

[0004] In conventional technology, in order to further advance dearomatization in addition to advanced desulfurization, one possible method is to use the existing catalyst system to reduce the reaction space velocity, i.e., reduce the processing volume or add more reactors, but this is not very reasonable from an economic standpoint.The second method is to use a two-stage process technology in which, after conventional hydrogenation, the produced oil is stripped to remove hydrogen sulfide and then placed in a precious metal hydrogenation reactor, but this significantly increases the cost of using the catalyst and complicates the process, making it not the best solution.

[0005] CN108085058B discloses a method for the advanced dearomatization of hydrocarbon oils. In this method, feedstock oil and hydrogen gas are passed through a highly dispersed Pt-Pd / Al2O3 catalyst under relatively mild temperature and pressure conditions. The gas phase after the reaction is compressed and recycled, while the liquid phase is a product with a low aromatic hydrocarbon content. However, while the Pt-Pd / Al2O3 hydrogenation catalyst is primarily suitable for dearomatization of low-sulfur diesel feedstocks, its effectiveness in desulfurizing and dearomatizing low-quality diesel is insufficient.

[0006] CN109926067A discloses a platinum-palladium-cobalt trimetallic hydrodearomatization catalyst and its preparation method. This method employs a stepwise impregnation method of active metal precursors. The resulting catalyst exhibits high utilization of the platinum and palladium precious metals and a high synergistic catalytic activity. Furthermore, the addition of platinum and palladium improves the hydrogenation performance of non-precious metal cobalt to aromatic hydrocarbons. However, to avoid the impact of hydrogen sulfide on advanced dearomatization by precious metals, this catalyst is intended for hydrocarbon oils after the basic removal of sulfur-containing compounds. Therefore, it cannot achieve desulfurization and dearomatization of low-quality diesel. Summary of the Invention [Problem to be solved by the invention]

[0007] In view of the shortcomings of the prior art, the present invention provides a method and system for hydrogenating hydrocarbon oils, which can achieve high hydrogenation effects, simplify the overall process flow, reduce the severity of the reaction, and improve the efficiency of the chemical reaction. [Means for solving the problem]

[0008] A first aspect of the present invention is Step (1) of subjecting a hydrocarbon oil feedstock to a gas-phase desulfurization reaction in a gas-phase hydrogenation reactor in the presence of hydrogen gas to obtain a gas-phase desulfurization reaction product; (2) pressurizing the vapor-phase desulfurization reaction product to obtain an pressurized stream; and (3) sending the pressurized stream to a liquid-phase hydrogenation reactor, and subjecting a liquid-phase component in the pressurized stream to a liquid-phase hydrogenation reaction in the liquid-phase hydrogenation reactor to obtain a liquid-phase hydrogenated reaction product.

[0009] Preferably, the conditions for the gas phase desulfurization reaction are a pressure of 0.1 to 2.8 MPa, preferably 0.5 to 2 MPa, a temperature of 260 to 400°C, preferably 320 to 390°C, a hydrogen / oil volume ratio of 100 to 900, preferably 300 to 700, and a space velocity of 0.5 to 3 h -1 , preferably 0.8 to 2 hours -1 Includes.

[0010] Preferably, the conditions for the liquid phase hydrogenation reaction are a pressure of 2 to 8 MPa, preferably 3 to 6 MPa, a temperature of 200 to 400°C, preferably 260 to 360°C, and a space velocity of 0.1 to 3 h -1 , preferably 0.5 to 1 hour -1 Includes.

[0011] A second aspect of the present invention is a method for producing a hydrogen-containing gas-phase hydrogenation reactor, comprising: a gas-phase hydrogenation reactor packed with a first hydrogenation catalyst; a pressure booster; and a liquid-phase hydrogenation reactor packed with a second hydrogenation catalyst, the gas-phase hydrogenation reactor being connected in series; The gas-phase hydrogenation reactor performs a gas-phase desulfurization reaction between a hydrocarbon oil feedstock and hydrogen gas to obtain a gas-phase desulfurization reaction product, the pressure booster boosts the vapor-phase desulfurization reaction product to obtain a boosted stream; The liquid-phase hydrogenation reactor brings the pressurized stream into contact with a second hydrogenation catalyst to carry out a liquid-phase hydrogenation reaction, thereby obtaining a liquid-phase hydrogenated reaction product, thereby providing a system for hydrogenating a hydrocarbon oil. [Effects of the Invention]

[0012] The hydrogenation method and system of the present invention have the following advantages over the prior art:

[0013] (1) In the hydrogenation method and system of the present invention, reactive low molecular weight compounds are removed in a gas-phase hydrogenation reactor, unreacted high molecular weight compounds are liquefied by slight pressure increase and enter a liquid-phase hydrogenation reactor, and the liquefiable heavy components undergo advanced hydrotreating reactions. In this way, advanced desulfurization and dearomatization are performed in the same reaction system, avoiding the drawback of the prior art of incompatible reaction conditions. The inventors have discovered through research that subjecting hydrocarbon oils to gas-phase hydrodesulfurization can significantly reduce the competitive adsorption of other substances in the hydrocarbon oil, such as aromatic hydrocarbons, which is beneficial to the targeted desulfurization reaction. Furthermore, by linking the process with a liquid-phase hydrogenation reactor, the subsequent advanced removal of other substances in the hydrocarbon oil, such as dearomatization, can be more easily achieved.

[0014] (2) In the hydrogenation method and system of the present invention, the gas-phase desulfurization reaction product is pressurized to promote the simultaneous liquefaction of hydrogen gas and oil. Furthermore, since the dissolution patterns of hydrogen gas and hydrogen sulfide in petroleum products are different, the influence of hydrogen sulfide on the catalytic activity when entering the subsequent liquid-phase hydrogenation reactor can be avoided. This fully avoids the inhibitory effect of hydrogen sulfide on the deep desulfurization in conventional liquid-phase hydrogenation technology, and also eliminates the need for hydrogen sulfide stripping between the two reactors.

[0015] (3) This invention enables the hydrorefining of hydrocarbon oils under milder operating conditions and a simpler process flow, such as advanced desulfurization and dearomatization using low-quality diesel as a feedstock. Among the gas-phase desulfurization reaction products, the reacted low-molecular-weight fractions are not liquefied during the pressure-boosting process but are liquefied after high-pressure separation through a heat exchanger. This liquefaction method is advantageous for separating hydrogen gas from the feedstock, allowing large amounts of hydrogen gas to be recovered and recycled, improving hydrogen utilization efficiency. The hydrogenated light fractions that have undergone high-pressure separation are mixed with the hydrogenated heavy fractions and then enter the subsequent stripping and fractionation system. The entire reaction system eliminates the need for a hydrogen gas compressor in a fixed-bed reaction system and a circulating oil pump in a liquid-phase hydrogenation reaction system, thereby reducing investment costs, simplifying process steps, improving reaction efficiency, and reducing reaction severity. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a schematic diagram of a method and system for hydrogenating hydrocarbon oils according to a particular embodiment of the present invention. [Figure 2] FIG. 1 is a schematic diagram of a method and system for hydrogenating hydrocarbon oils according to another specific embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] The endpoints of ranges and any values ​​disclosed herein are not intended to be limiting to the exact ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. In the case of numerical ranges, values ​​between the individual range endpoints, between the individual range endpoints and the individual point values, and between the individual point values ​​can be combined with each other to form one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed herein.

[0018] The description of the exemplary embodiments is intended to be read with reference to the drawings, which are to be considered part of the entire written description. In the specification, relative terms such as "lower," "upper," "horizontal," "vertical," "upper," "lower," "upward," "downward," "top," and "bottom," and their derivatives (e.g., "horizontally," "below," "on top," etc.), should be interpreted as the orientation shown in the drawings being described at the time. These relative terms are for ease of description and do not require that devices be constructed or operated in a particular orientation. Unless otherwise specified, the term "connected" in the present invention refers to a relationship in which structures are fixed or connected to each other directly or indirectly through intermediate structures.

[0019] A first aspect of the present invention is Step (1) of subjecting a hydrocarbon oil feedstock to a gas-phase desulfurization reaction in a gas-phase hydrogenation reactor in the presence of hydrogen gas to obtain a gas-phase desulfurization reaction product; (2) pressurizing the vapor-phase desulfurization reaction product to obtain an pressurized stream; and (3) sending the pressurized stream to a liquid-phase hydrogenation reactor, and subjecting a liquid-phase component in the pressurized stream to a liquid-phase hydrogenation reaction in the liquid-phase hydrogenation reactor to obtain a liquid-phase hydrogenated reaction product.

[0020] The hydrogen gas in step (1) of the present invention can be any hydrogen-containing gas, including fresh hydrogen gas, recycled hydrogen, or hydrogen-rich gas. Those skilled in the art can clearly understand the hydrogen-containing gas of the present invention after understanding the technical solution of the present invention.

[0021] The present invention allows for a wide range of hydrocarbon oil feedstocks to be selected, and the method of the present invention is suitable for any hydrocarbon oil, including at least one of low-quality diesel, aviation kerosene, wax oil, and naphtha, from which low-molecular-weight sulfides and other high-molecular-weight impurities must be simultaneously removed. The method of the present invention mainly removes low-molecular-weight sulfides in a gas-phase hydrogenation reactor, and the unreacted high-molecular-weight impurities are liquefied by slight pressure increase and enters a liquid-phase hydrogenation reactor, where the heavy components that are easily liquefied undergo a high-level hydrotreating reaction.

[0022] In the present invention, the properties of the hydrocarbon oil feedstock can be selected from a wide range. Preferably, the low-quality diesel has an initial boiling point of 150 to 200°C, a final boiling point of 320 to 400°C, an S content of ≦20,000 μg / g, preferably ≦15,000 μg / g, an N content of ≦1,000 μg / g, preferably ≦800 μg / g, and a polycyclic aromatic hydrocarbon content of ≦50 wt%. For example, the low-quality diesel may have an S content of 8,000 μg / g, 9,000 μg / g, 10,000 μg / g, or 11,500 μg / g, but is not limited to these. The N content may be 500 μg / g, 600 μg / g, or 700 μg / g, but is not limited to these. The polycyclic aromatic hydrocarbon content may be 25 wt%, 30 wt%, 35 wt%, 40 wt%, or 45 wt%, but is not limited to these.

[0023] Preferably, the aviation kerosene has an initial boiling point of 80 to 150°C, a final boiling point of 200 to 300°C, an S content of ≦8000 μg / g, preferably ≦4000 μg / g, and an N content of ≦100 μg / g, preferably ≦20 μg / g. For example, the S content of the aviation kerosene may be, but is not limited to, 500 μg / g, 1000 μg / g, 2000 μg / g, or 3000 μg / g, and the N content may be, but is not limited to, 5 μg / g, 10 μg / g, or 15 μg / g.

[0024] Preferably, the wax oil has an initial boiling point of 160 to 220°C, a final boiling point of 300 to 400°C, an S content of 30,000 μg / g or less, preferably 20,000 μg / g or less, an N content of 2,000 μg / g or less, preferably 1,500 μg / g or less, and a polycyclic aromatic hydrocarbon content of 60 wt% or less. For example, the S content of the wax oil may be, but is not limited to, 500 μg / g, 1,000 μg / g, 2,000 μg / g, 5,000 μg / g, 8,000 μg / g, 9,000 μg / g, 10,000 μg / g, or 15,000 μg / g, and the N content may be, but is not limited to, 500 μg / g, 700 μg / g, 1,000 μg / g, or 1,200 μg / g. The content of polycyclic aromatic hydrocarbons may be, but is not limited to, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, and the like.

[0025] In the present invention, the symbol "≦" means less than or equal to, and the symbol "≧" means greater than or equal to.

[0026] According to one preferred embodiment of the present invention, the gas-phase desulfurization reaction is carried out in the presence of a first hydrogenation catalyst, which is a catalyst having a hydrodesulfurization function. In the present invention, the catalyst having a hydrodesulfurization function can be selected from a wide range of options and may be selected from conventional options in the art. For example, the catalyst having a hydrodesulfurization function includes a support and a hydrogenation-active metal, where the support is an inorganic refractory oxide, typically one or more selected from alumina, amorphous silicon aluminum, silica, titanium oxide, etc., and the hydrogenation-active metal includes a Group VIB metal component and / or a Group VIII metal component. In the catalyst having a hydrodesulfurization function, the Group VIB metal component is preferably selected from tungsten and / or molybdenum, and its content in the catalyst in terms of oxide mass is 5% to 30%, preferably 15% to 30%. The Group VIII metal component is preferably selected from nickel and / or cobalt, and its content in the catalyst in terms of oxide mass is 1% to 6%, preferably 2% to 6%. The hydrodesulfurization catalyst may further contain an auxiliary component such as at least one of phosphorus, silicon, boron, magnesium, fluorine, etc., and the mass content of this auxiliary component in the hydrodesulfurization catalyst is generally 6 wt% or less.

[0027] The catalyst having hydrodesulfurization function may be prepared by any method, and may be a commercially available catalyst, such as at least one of FHUDS-5, FHUDS-6, and FHUDS-7 catalysts developed by Sinopec Fushun Petrochemical Industry Research Institute (FRIPP).

[0028] According to the method of the present invention, the conditions for the gas-phase desulfurization reaction are preferably a pressure of 0.1 to 2.8 MPa, preferably 0.5 to 2 MPa, a temperature of 260 to 400°C, preferably 320 to 390°C, a hydrogen / oil volume ratio of 100 to 900, preferably 300 to 700, and a space velocity of 0.5 to 3 h -1 , preferably 0.8 to 2 hours -1In the method according to the present invention, when the gas-phase hydrodesulfurization reaction is carried out at this preferred hydrogen / oil volume ratio, the partial pressure of the feedstock can be reduced, which further helps to achieve complete vaporization of the feedstock. In addition, the gas-phase desulfurization reaction of the present invention can be carried out at a lower pressure, thereby significantly reducing energy consumption.

[0029] In the gas-phase desulfurization reaction in step (1), not only the sulfur content in the hydrocarbon oil feedstock is removed, but also the nitrogen content is inevitably removed.

[0030] In the present invention, the type of the gas phase hydrogenation reactor is particularly limited, and preferably, the gas phase hydrogenation reactor is a fixed bed reactor.

[0031] In step (2) of the present invention, the gas-phase desulfurization reaction product is pressurized. The pressurization may be performed by a pressure booster, for example, a compressor. The type of the compressor is not particularly limited and may be, for example, a reciprocating compressor or a centrifugal compressor.

[0032] In the present invention, the pressure range of the gas-phase desulfurization reaction product can be selected widely, and it is preferable to pressure-increase the product to ensure normal supply to the liquid-phase hydrogenation reactor and meet the operating pressure requirements of the liquid-phase hydrogenation reactor. In the present invention, the pressure of the gas-phase desulfurization reaction product is increased to promote the simultaneous liquefaction of hydrogen gas and oil. Furthermore, the solubility of hydrogen gas and hydrogen sulfide in petroleum products is different. That is, under high temperature conditions, the solubility of hydrogen gas is high and the solubility of hydrogen sulfide is low, so the concentration of hydrogen gas in the liquefied liquid phase is high and the concentration of hydrogen sulfide is low. This avoids the impact of hydrogen sulfide on catalyst activity when entering the subsequent liquid-phase hydrogenation reactor, and eliminates the need for hydrogen sulfide stripping between the two reactors.

[0033] According to one preferred embodiment of the present invention, in step (2), the gas-phase desulfurization reaction product is pressurized to 2 to 10 MPa, preferably 2.5 to 7.5 MPa. The pressure range may vary depending on the hydrocarbon feedstock and the requirements of various products.

[0034] Preferably, the hydrocarbon oil feedstock is low-quality diesel, and in step (2), the gas-phase desulfurization reaction product is pressurized to 4.5 to 6.5 MPa. In this preferred embodiment, the liquid-phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, which is a hydro-dearomatization catalyst. When the hydrocarbon oil feedstock is low-quality diesel, the method of the present invention performs advanced desulfurization and dearomatization in the same reaction system, avoiding the drawback of incompatible reaction conditions. Controlling the reaction conditions in the gas-phase hydrogenation reactor reduces the adsorption of aromatic ring-containing substances on the catalyst surface, significantly reducing competitive adsorption of aromatic hydrocarbon substances and contributing to the desired desulfurization reaction. Furthermore, controlling the reaction conditions in the gas-phase hydrogenation reactor not only promotes gas-phase desulfurization, but also promotes subsequent advanced dearomatization by more appropriately coordinating with the liquid-phase hydrogenation reactor.

[0035] According to another preferred embodiment of the present invention, the hydrocarbon oil feedstock is low-quality diesel, and in step (2), the pressure of the vapor-phase desulfurization reaction product is increased to 4 to 7 MPa. In this preferred embodiment, the liquid-phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is an advanced hydrodesulfurization catalyst. In this preferred embodiment, the method of the present invention can effectively remove high molecular weight sulfides at a relatively low temperature and appropriate pressure. If it is necessary to further remove polycyclic aromatic hydrocarbons, the production of high-quality diesel products can be achieved by selecting an advanced hydrodesulfurization catalyst (e.g., a Mo-Ni catalyst) that also has the function of removing polycyclic aromatic hydrocarbons.

[0036] According to another preferred embodiment of the present invention, the hydrocarbon oil feedstock is aviation kerosene, and in step (2), the gas-phase desulfurization reaction product is pressurized to 2.5 to 4 MPa. In this preferred embodiment, the liquid-phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is a hydrodearomatization catalyst. When the hydrocarbon oil feedstock is aviation kerosene, the method of the present invention can effectively remove aromatic hydrocarbons from aviation kerosene and improve the smoke point of the aviation kerosene. In particular, when heavy components are removed from aviation kerosene fractions to increase the aromatic hydrocarbon content in the feedstock in order to increase the production of aviation kerosene, a reaction environment suitable for removing aromatic hydrocarbons is more preferable, and the production of high-smoke-point aviation kerosene can be achieved.

[0037] According to another preferred embodiment of the present invention, the hydrocarbon oil feedstock is aviation kerosene, and in step (2), the vapor-phase desulfurization reaction product is pressurized to 2.5 to 4 MPa. In this preferred embodiment, the liquid-phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is a hydroisomerization catalyst. When the hydrocarbon oil feedstock is aviation kerosene, the method of the present invention can effectively isomerize branched alkanes in aviation kerosene. In particular, when heavy components are removed from the aviation kerosene fraction to increase the content of long-chain alkanes in the feedstock in order to increase the production of aviation kerosene, a reaction environment suitable for alkane isomerization is more preferable, and the production of aviation kerosene with a low freezing point can be achieved.

[0038] According to another preferred embodiment of the present invention, the hydrocarbon oil feedstock is a wax oil, and in step (2), the gas-phase desulfurization reaction product is pressurized to 5 to 10 MPa. In this preferred embodiment, the liquid-phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is an isomerization pour point depressing catalyst. In this preferred embodiment, the method of the present invention can improve the viscosity index of a specialty oil product by isomerizing long-chain alkanes in the wax oil fraction. When the hydrocarbon oil feedstock is a wax oil, preferably, the method may further include a step of transferring the gas-phase components in the pressurized stream upward and discharging them from the liquid-phase hydrogenation reactor, optionally subjecting them to a removal treatment to obtain a hydrogenated light component, and then mixing the hydrogenated light component with the liquid-phase hydrogenation reaction product and subjecting them to a hydrodearomatization reaction to obtain a specialty oil product such as white oil. The hydrodearomatization reaction may be carried out in a third hydrogenation reactor in the presence of a hydrodearomatization catalyst. In the present invention, the form of the third hydrogenation reactor is not particularly limited, and may be a fixed-bed hydrogenation reactor. The reaction conditions can be selected from a wide range, as long as the hydrodearomatization can be carried out smoothly.

[0039] In the present invention, the second hydrogenation catalyst may be selected from a wide range of types, provided that it can achieve the above-mentioned object. For example, the second hydrogenation catalyst may be a hydrodearomatization catalyst having a hydrodearomatization hydrocarbon function, a hydroisomerization catalyst having a hydroisomerization function, an advanced hydrodesulfurization catalyst having an advanced hydrodesulfurization function, or an isomerization pour point depressing catalyst having an isomerization pour point depressing function.

[0040] According to a preferred embodiment of the present invention, the hydrodearomatization catalyst may be a non-noble metal catalyst or a noble metal catalyst. The non-noble metal catalyst may include a support and a hydrogenation-active metal. The support is an inorganic refractory oxide, typically one or more selected from alumina, amorphous silicon aluminum, silica, and titanium oxide, preferably alumina. The hydrogenation-active metal includes a Group VIB metal component and / or a Group VIII metal component. In the hydrodearomatization catalyst, the Group VIB metal component is preferably selected from tungsten and / or molybdenum, and its oxide content in the catalyst is 5% to 30%, preferably 15% to 30%, by mass. The Group VIII metal component is preferably selected from nickel and / or cobalt, and its oxide content in the catalyst is 1% to 6%, preferably 2% to 5%, by mass. The hydrodesulfurization catalyst may further contain an auxiliary component such as at least one of phosphorus, silicon, boron, magnesium, fluorine, etc., and the mass content of this auxiliary component in the catalyst having hydrodesulfurization function is generally 6 wt% or less. The hydrodesulfurization catalyst is preferably a Mo-Ni type catalyst.

[0041] The hydrodearomatization catalyst may be prepared by any method, and may be a commercially available catalyst, such as at least one of FHUDS-10, FHUDS-6, and FHUDS-8 developed by Sinopec Fushun Petrochemical Industry Research Institute (FRIPP).

[0042] The noble metal catalyst preferably has Pt, Pd, etc. as the active metal, and may be prepared by any method, or may be a commercially available catalyst, such as the FHDA-10 catalyst developed by Sinopec Fushun Petrochemical Industry Research Institute (FRIPP).

[0043] According to one preferred embodiment of the present invention, the hydroisomerization catalyst may be any catalyst capable of performing hydroisomerization function, and preferably, the catalyst comprises alumina doped with molecular sieves (including, but not limited to, at least one of ZSM-5, Y, and β molecular sieves) as a support and a Group VIII metal (including, but not limited to, Ni) as an active component, and may be prepared by any method, or may be a commercially available catalyst such as the FDW-3 catalyst developed by Sinopec Fushun Petrochemical Industry Research Institute (FRIPP).

[0044] According to one preferred embodiment of the present invention, the advanced hydrodesulfurization catalyst may be any catalyst capable of performing the function of removing polymeric sulfur, the catalyst support is preferably alumina, and the active component is a Group VIB metal or a Group VIII metal, which may be selected as described above. The catalyst may be prepared by any method, or may be a commercially available catalyst such as the FHUDS-5 or FHUDS-7 catalyst developed by Sinopec Fushun Petrochemical Research Institute (FRIPP).

[0045] In the present invention, the isomerization pour point depressing catalyst is not particularly limited and may be any of various isomerization pour point depressing catalysts commonly used in the prior art. The active components and carriers thereof may be selected in the same manner as those of the hydroisomerization catalyst described above, but are not described in detail in the present invention.

[0046] In the present invention, the catalyst having the specific function does not only exhibit that function, but also exhibits that function primarily. For example, the hydrodesulfurization catalyst does not only exhibit hydrodesulfurization function, but also exhibits hydrodesulfurization function primarily in its application environment.

[0047] According to a preferred embodiment of the present invention, the pressure of the liquid-phase hydrogenation reaction is higher than the pressure of the vapor-phase hydrodesulfurization reaction by at least 1 MPa, preferably 1.5 to 7 MPa, more preferably 2.5 to 6 MPa. The method according to the present invention allows the reaction to be carried out under medium to low pressure, thereby significantly reducing the severity of the reaction and saving energy consumption.

[0048] According to the method of the present invention, the conditions for the liquid phase hydrogenation reaction are preferably a pressure of 2 to 8 MPa, preferably 3 to 6 MPa, a temperature of 200 to 400°C, preferably 260 to 360°C, and a space velocity of 0.1 to 3 h -1 , preferably 0.5 to 1 hour -1 Includes.

[0049] In the present invention, the type of the liquid-phase hydrogenation reactor is not particularly limited, and preferably, the liquid-phase hydrogenation reactor is a fixed-bed reactor.

[0050] According to one preferred embodiment of the present invention, the liquid-phase hydrogenation reactor is a fixed-bed reactor equipped with a gas-liquid separation zone. The gas-liquid separation zone may be any zone capable of achieving separation, for example, in the case of a flash zone, the liquid-phase hydrogenation reactor is a fixed-bed reactor equipped with a flash zone.

[0051] Specifically, a flash zone is provided within the liquid-phase hydrogenation reactor, and no catalyst is packed into the flash zone or above, with the liquid-phase hydrogenation reaction zone below the flash zone. A stream (gas-liquid mixed phase) obtained by pressurizing the vapor-phase desulfurization reaction product is supplied to the flash zone of the liquid-phase hydrogenation reactor, the resulting vapor-phase components move upward and are discharged from the liquid-phase hydrogenation reactor, and the resulting liquid-phase components move downward and undergo the liquid-phase hydrogenation reaction. The resulting liquid-phase hydrogenation reaction product, the hydrogenated heavy components, are discharged from the bottom of the liquid-phase hydrogenation reactor.

[0052] According to one preferred embodiment of the present invention, the gas phase components in the pressurized stream are allowed to move upwardly and discharged from the liquid phase hydrogenation reactor, and are optionally subjected to a de-impurity treatment to obtain hydrogenated light components.

[0053] In the present invention, the removal of impurities can be performed in a wide range of processes, including, but not limited to, dehydrogenation. Preferably, the removal of impurities is performed by dehydrogenation, preferably by heat exchange of the gas phase components followed by high-pressure separation to obtain the hydrogenated light components and hydrogen sulfide-containing hydrogen gas. In the method of the present invention, the reacted low molecular weight components in the gas phase desulfurization reaction product are not liquefied during pressure increase but are liquefied by heat exchange and high-pressure separation. This liquefaction method is advantageous for separating hydrogen gas from the feedstock, allowing for the recovery and recycling of large amounts of hydrogen gas, thereby increasing the utilization rate of hydrogen gas. The high-pressure separated hydrogenated light components are mixed with the hydrogenated heavy components and subjected to a subsequent stripping and fractionation system. The entire reaction system does not require a hydrogen gas compressor in a fixed-bed reaction system or a circulating oil pump in a liquid-phase hydrogenation reaction system, thereby reducing investment costs, simplifying the chemical process flow, improving reaction efficiency, and reducing reaction severity.

[0054] The heat exchange may be performed in a heat exchanger. The high-pressure separation may be performed in a high-pressure separator. In the present invention, the conditions for the heat exchange and high-pressure separation are not particularly limited as long as the above-mentioned object is achieved.

[0055] Preferably, the temperature of the gas phase component is lowered to 100 to 200°C, more preferably 120 to 150°C, by the heat exchange.

[0056] According to one preferred embodiment of the present invention, the method may further comprise the step of mixing the liquid-phase hydrogenation reaction product (also referred to as the hydrogenated heavy component) with the hydrogenated light component to obtain a hydrogenated product.

[0057] According to a preferred embodiment of the present invention, the method may further include stripping (hydrogen desulfurization) and fractionating the hydrogenated product to obtain a desired product. The specific conditions for the stripping and fractionation are not particularly limited and can be controlled according to the requirements of the feedstock and the performance of the desired product. For example, if the hydrocarbon oil feedstock is low-quality diesel, the hydrogenated product is stripped and fractionated to remove the naphtha fraction and obtain a refined diesel product.

[0058] Preferably, the hydrogenation product is a diesel refinery product having an aromatic hydrocarbon content of 5 wt% or less and an S content of 10 μg / g or less.

[0059] Preferably, the hydrogenation product is a refined aviation kerosene product having a smoke point of 26 mm or more and / or a freezing point of -50°C or less.

[0060] Preferably, the hydrogenated product is a specialty oil product having an aromatic hydrocarbon content of 5 wt% or less and an S content of 10 μg / g or less.

[0061] A second aspect of the present invention is a method for producing a hydrogen-containing gas-phase hydrogenation reactor, comprising: a gas-phase hydrogenation reactor packed with a first hydrogenation catalyst; a pressure booster; and a liquid-phase hydrogenation reactor packed with a second hydrogenation catalyst, the gas-phase hydrogenation reactor being connected in series; The gas-phase hydrogenation reactor performs a gas-phase desulfurization reaction between a hydrocarbon oil feedstock and hydrogen gas to obtain a gas-phase desulfurization reaction product, the pressure booster boosts the vapor-phase desulfurization reaction product to obtain a boosted stream; The liquid-phase hydrogenation reactor brings the pressurized stream into contact with a second hydrogenation catalyst to carry out a liquid-phase hydrogenation reaction, thereby obtaining a liquid-phase hydrogenated reaction product, thereby providing a system for hydrogenating a hydrocarbon oil.

[0062] Preferably, the pressure booster boosts the gas-phase desulfurization reaction product to a pressure of 2 to 10 MPa, preferably 2.5 to 7.5 MPa. In the present invention, the type of the pressure booster is not particularly limited and may be, for example, a compressor, and the type of the compressor is not particularly limited and may be, for example, a reciprocating compressor or a centrifugal compressor.

[0063] In the system according to the present invention, the types of the first hydrogenation catalyst and the second hydrogenation catalyst may be selected depending on the type of hydrocarbon oil feedstock, specifically, they can be selected depending on the content described in the first aspect, and therefore will not be described in detail here.

[0064] Preferably, the hydrocarbon oil feedstock is diesel, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is a hydrodearomatization catalyst; or the hydrocarbon oil feedstock is diesel, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is an advanced hydrodesulfurization catalyst; or the hydrocarbon oil feedstock is aviation kerosene, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is a hydrodearomatization catalyst; or the hydrocarbon oil feedstock is aviation kerosene, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is a hydroisomerization catalyst; or The hydrocarbon oil feedstock is a waxy oil, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is an isomerization pour point reducing catalyst.

[0065] The selection of the first hydrogenation catalyst and the second hydrogenation catalyst is similarly as described in the first embodiment, and therefore will not be described in detail here.

[0066] According to the system of the present invention, preferably, the gas phase hydrogenation reactor is a fixed bed reactor.

[0067] According to one preferred embodiment of the present invention, the liquid-phase hydrogenation reactor is provided with an outlet for gaseous components at its top and an outlet for liquid-phase hydrogenation reaction products at its bottom.

[0068] In the system according to the present invention, the liquid-phase hydrogenation reactor is preferably a fixed-bed reactor, preferably a fixed-bed reactor provided with a gas-liquid separation zone. Specifically, the gas-liquid separation zone may be any zone capable of achieving separation. For example, in the case of a flash zone, the liquid-phase hydrogenation reactor is a fixed-bed reactor provided with a flash zone. Specifically, the liquid-phase hydrogenation reactor is provided with a flash zone, and no catalyst is packed in the flash zone or above it. The liquid-phase hydrogenation reaction zone is located below the flash zone. That is, preferably, the gas-liquid separation zone is located above the liquid-phase reaction zone. The gas-phase desulfurization reaction product is pressurized and the resulting stream (gas-liquid mixed phase) is supplied to the flash zone of the liquid-phase hydrogenation reactor. The resulting gas phase component moves upward and is discharged from the top outlet of the liquid-phase hydrogenation reactor. The resulting liquid phase component moves downward and undergoes liquid-phase hydrogenation. The resulting liquid-phase hydrogenation reaction product, the hydrogenated heavy component, is discharged from the bottom outlet of the liquid-phase hydrogenation reactor.

[0069] According to one preferred embodiment of the present invention, the system further includes a de-impurity device, the inlet of which is connected to the outlet for the gas phase component of the liquid-phase hydrogenation reactor, and which performs impurity removal treatment on the gas phase component in the pressurized stream discharged from the liquid-phase hydrogenation reactor to obtain a hydrogenated light component.

[0070] Preferably, the impurity removal device is a hydrogen desulfurization device.

[0071] Preferably, the desulfurization unit includes a heat exchange unit and a high pressure separation unit in communication.

[0072] In the system according to the present invention, the gas phase component outlet of the liquid-phase hydrogenation reactor is preferably connected to the inlet of a heat exchanger, and the outlet of the heat exchanger is preferably connected to the inlet of the high-pressure separation device. The gas phase component is subjected to heat exchange and high-pressure separation to obtain the hydrogenated light component and hydrogen sulfide-containing hydrogen gas. The hydrogen-rich gas obtained by treating the hydrogen sulfide-containing hydrogen gas can be recycled.

[0073] Preferably, the heat exchanger reduces the temperature of the gas phase component to preferably 100 to 200°C, more preferably 120 to 150°C.

[0074] According to one preferred embodiment of the present invention, the system further comprises a mixer for receiving and mixing the liquid-phase hydrogenated reaction product and the hydrogenated light component to obtain a hydrogenated product.

[0075] Specifically, the gas phase outlet of the liquid-phase hydrogenation reactor is connected in sequence to a heat exchanger and a high-pressure separator, and the liquid phase outlet pipeline at the bottom of the liquid-phase hydrogenation reactor is connected to the liquid phase outlet pipeline at the bottom of the high-pressure separator, which jointly supply the mixer.

[0076] According to one preferred embodiment of the present invention, the system further includes a stripping and fractionation device, which strips (dehydrogenates) and fractionates the hydrogenated product. The specific conditions for the stripping and fractionation are not particularly limited and can be operated according to the requirements of the raw material and the performance of the target product. The specific conditions are as described above.

[0077] When the hydrocarbon oil feedstock is wax oil, preferably, the system further includes a third hydrogenation reactor packed with a third hydrogenation catalyst (preferably a hydrodearomatization catalyst), and the third hydrogenation reactor has an inlet connected to the liquid-phase hydrogenation reaction product outlet of the liquid-phase hydrogenation reactor and the hydrogenated light component outlet of the impurity removal device, and performs a hydrodearomatization reaction of the hydrogenated light component and the liquid-phase hydrogenation reaction product.

[0078] The following examples further illustrate the aspects and effects of the present invention.

[0079] In the present invention, percentages and percentage contents are by weight unless otherwise stated.

[0080] The method and system of the present invention will be described in detail below with reference to FIG. 1. An example will be described in which the hydrocarbon oil feedstock is diesel. Diesel feedstock and hydrogen gas 1 are introduced into a gas-phase hydrogenation reactor 2 (also referred to as a first hydrogenation reactor) to undergo a gas-phase desulfurization reaction, yielding a gas-phase desulfurization reaction product 3. The mixture is then introduced into a pressure booster 4 (compressor) and pressurized by the compressor, before being introduced into a liquid-phase hydrogenation reactor 5 (also referred to as a second hydrogenation reactor) equipped with a flash zone. The liquid-phase component flows downward into the reaction zone and undergoes a hydrodearomatization reaction, yielding a liquid-phase hydrogenation reaction product 6 (hydrogenated heavy component). The gas-phase component 7 flows upward from the liquid-phase hydrogenation reactor and enters a heat exchanger 8. Then, it enters a high-pressure separator 9, where it is separated into a hydrogenated light component 11 and a hydrogen sulfide-containing hydrogen gas 10. The liquid-phase hydrogenation reaction product 6 and the hydrogenated light component 11 are mixed and introduced into a stripping and fractionation unit 12, ultimately yielding a diesel refinery product 13. Examples 1 to 3

[0081] The flow diagram shown in Figure 1 was used. Two 100 mL fixed-bed hydrogenation reactors, one gas-phase hydrogenation reactor and one liquid-phase hydrogenation reactor, were connected in series. A conventional reciprocating compressor was installed between the reactors. The gas-phase hydrogenation reactor was filled with 50 mL of Mo-Co-type diesel hydrogenation catalyst A, and the liquid-phase hydrogenation reactor was filled with 50 mL of Mo-Ni-type diesel hydrogenation catalyst B, with a flash zone installed above them. A gas-phase outlet was installed above the liquid-phase hydrogenation reactor. This gas-phase outlet was connected in sequence to a heat exchanger (cooled to 130 °C) and a high-pressure separator. A liquid-phase outlet was installed at the bottom of the liquid-phase hydrogenation reactor. The liquid-phase outlet pipeline and the liquid-phase outlet pipeline at the bottom of the high-pressure separator were connected together and fed to the subsequent stripping and fractionation unit, where the naphtha fraction was removed and a refined diesel product (initial boiling point 150 °C) was obtained. The raw material used was a mixture of straight-run diesel, coked diesel, and catalytic diesel. The catalyst properties are shown in Table 1, the feedstock properties in Table 2, and the reaction process conditions and results in Table 3. Comparative Example 1

[0082] A typical fixed-bed diesel hydrogenation process flow was used, with one hydrogenation reactor, i.e., the first hydrogenation reactor. According to the conventional catalyst formulation, the Mo-Ni catalyst B was loaded on top and the Mo-Co catalyst A on the bottom, with a loading volume of 50 mL. Generally, high-pressure separation, low-pressure separation, stripping, and other processes were performed after the reactor to obtain diesel products. Hydrogen sulfide was removed from the hydrogen gas and the gas was compressed in a cycle hydrogen compressor for recycling. The feedstock and catalyst properties were the same as in Examples 1 to 3. The reaction process conditions and results are shown in Table 3. Comparative Example 2

[0083] A typical diesel fixed-bed hydrogenation process flow was used, and one hydrogenation reactor, i.e., the first hydrogenation reactor, was configured. Following the same catalyst formulation order as in Examples 1 to 3, Mo-Co type catalyst A was packed at the top and Mo-Ni type catalyst B at the bottom, with a packed volume of 50 mL each. Generally, high-pressure separation, low-pressure separation, stripping, and other processes were performed after the reactor to obtain diesel products. Hydrogen sulfide was removed from the hydrogen gas, and the gas was pressurized using a cycle hydrogen compressor for recycling. The raw materials and catalyst were the same as in Examples 1 to 3. The reaction process conditions and results are shown in Table 3. Comparative Example 3

[0084] A typical diesel fixed-bed hydrogenation process flow was used. Two hydrogenation reactors, reactor 1 and reactor 2, were connected in series, with a stripping tower installed between the two reactors. Reactor 1 was filled with 50 mL of Mo-Co diesel hydrogenation catalyst A, and reactor 2 was filled with 50 mL of Mo-Ni diesel hydrogenation catalyst B. Generally, high-pressure separation, low-pressure separation, stripping, and other processes were performed after the reactors to obtain diesel products. Hydrogen sulfide was removed from the hydrogen gas, and the gas was pressurized using a cycle hydrogen compressor for recycling. The raw materials and catalysts were the same as in Examples 1 to 3. The reaction process conditions and results are shown in Table 3. Comparative Example 4

[0085] Aside from the installation of a high-power reciprocating compressor between the first and second hydrogenation reactors and the control of the process conditions, the hydrogenation process steps were the same as those in Examples 1 to 3. The reaction process conditions and results are shown in Table 3.

[0086] [Table 1]

[0087] [Table 2]

[0088] [Table 3]

[0089] As can be seen from Table 3, in Comparative Example 1, which used conventional fixed-bed hydrogenation technology and a conventional catalyst packing system, hydrogenation of polycyclic aromatic hydrocarbons occurred in the upper part of the reactor, while deep desulfurization occurred in the lower part of the reactor. To achieve the deep desulfurization effect, it was difficult to achieve the right reaction conditions for aromatic hydrocarbon hydrogenation, resulting in poor removal of polycyclic aromatic hydrocarbons. In contrast, in the present invention, the pressure in the reaction system is significantly lowered, and because desulfurization and dearomatization are performed in two separate reaction systems, the reaction conditions can be optimized independently, resulting in better dearomatization results. In Comparative Example 2, the fixed-bed hydrogenation technology uses the same catalyst packing order as in the Example, and sulfides are removed at the top of the reactor, while the hydrogenation saturation reaction of aromatic hydrocarbons occurs at the bottom. Because the temperature at the bottom of the reactor rises significantly, the hydrogenation of aromatic hydrocarbons is thermodynamically limited, resulting in poor sulfide removal and aromatic hydrocarbon hydrogenation.

[0090] Both reactors used in Comparative Example 3 were conventional fixed-bed hydrogenation reactors, which had relatively harsh reaction conditions and high hydrogen and energy consumption. In addition, all of the effluent from the first reactor was fed to the second reactor, which increased the space velocity of aromatic hydrocarbon hydrogenation in the second reactor and reduced the effectiveness of removing polycyclic aromatic hydrocarbons.

[0091] In Comparative Example 4, the hydrogen / oil ratio in the gas-phase hydrogenation reactor was too high, which reduced the partial pressure of the feedstock oil, affecting the adsorption of sulfides onto the catalyst surface and resulting in insufficient desulfurization. Furthermore, the difficulty of liquefying the vaporized gas-phase reactor effluent was significantly increased, and even at a reaction pressure of 10 MPa, it was difficult to liquefy all of the heavy components, adversely affecting the removal of polycyclic aromatic hydrocarbons. Example 4

[0092] The flow diagram shown in Figure 1 was used. Two 100 mL fixed-bed hydrogenation reactors, one gas-phase and one liquid-phase, were connected in series. A conventional reciprocating compressor was installed between the reactors. The gas-phase hydrogenation reactor was filled with 50 mL of Mo-Ni hydrogenation catalyst A, and the liquid-phase hydrogenation reactor was filled with 50 mL of isomerization catalyst B (grade FDW-3), with a flash zone installed above them. A gas-phase outlet was installed above the liquid-phase hydrogenation reactor. This gas-phase outlet was connected to a heat exchanger (which cooled the gas phase components to 130 °C) and a high-pressure separator. A liquid-phase outlet was installed at the bottom of the liquid-phase hydrogenation reactor. The liquid-phase outlet pipeline and the liquid-phase outlet pipeline at the bottom of the high-pressure separator were connected and fed together to the subsequent stripping and fractionation unit. The catalyst properties are shown in Table 4, the feedstock properties are shown in Aviation Kerosene 1 in Table 5, and the reaction process conditions and results are shown in Table 6. Example 5

[0093] The flow diagram shown in Figure 1 was used. Two 100 mL fixed-bed hydrogenation reactors were connected in series with a reciprocating compressor between them. The first reactor was a gas-phase hydrogenation reactor packed with 50 mL of Mo-Ni diesel hydrogenation catalyst A, and the second reactor was a liquid-phase hydrogenation reactor packed with 50 mL of Ni-based hydrogenation catalyst C, with a flash zone installed above it. A gas-phase outlet was installed above the second reactor, and this gas-phase component outlet was connected in sequence to a heat exchanger (cooled to 130°C) and a high-pressure separator. The pipelines for the bottom liquid-phase outlets of the second reactor and the high-pressure separator were connected and led together to the subsequent stripping and fractionation equipment. The catalyst properties are shown in Table 4, the feedstock properties are shown in Table 5 for aviation kerosene 2, and the reaction process conditions and results are shown in Table 6. Example 6

[0094] The flow diagram shown in Figure 1 was used. Two 100 mL fixed-bed hydrogenation reactors, the first and second reactors, were connected in series. A conventional reciprocating compressor was installed between the reactors. The first reactor was a gas-phase desulfurization reactor packed with 50 mL of Mo-Ni diesel hydrodesulfurization catalyst D. The second reactor was a liquid-phase desulfurization reactor packed with 50 mL of Mo-Co diesel hydrodesulfurization catalyst E, with a flash zone installed above it. A gas-phase outlet was installed above the second reactor. This gas-phase outlet was connected in sequence to a heat exchanger (cooled to 130 °C) and a high-pressure separator. The bottom liquid-phase outlet pipeline of the second reactor and the bottom liquid-phase outlet pipeline of the high-pressure separator were connected and fed together to the subsequent stripping and fractionation unit, where the naphtha fraction was removed and a low-sulfur diesel product (initial boiling point 180 °C) was obtained. The catalyst properties are shown in Table 4, the feedstock properties are diesel in Table 5, and the reaction process conditions and results are shown in Table 6. Example 7

[0095] The flow diagram shown in Figure 2 was used. Three 100 mL fixed-bed hydrogenation reactors, the first reactor, the second reactor, and the third reactor, were connected in series. A conventional reciprocating compressor was installed between the first and second reactors. The first reactor was a gas-phase hydrogenation reactor filled with 50 mL of Mo-Co-type diesel hydrogenation catalyst E. The second reactor was a liquid-phase hydrogenation reactor filled with 50 mL of Ni-type isomerization pour point depressant catalyst B, with a flash zone installed above it. A gas-phase outlet was installed above the second reactor. This gas-phase outlet was connected in sequence to a heat exchanger (cooled to 130 °C) and a high-pressure separator. The bottom liquid-phase outlet pipeline of the second reactor and the bottom liquid-phase outlet pipeline of the high-pressure separator were connected and flowed together into the third reactor, which was filled with 50 mL of Mo-Ni-type advanced hydrogenation catalyst D. The final specialty oil product was obtained. The catalyst properties are shown in Table 4, the feedstock properties are wax oil in Table 5, and the reaction process conditions and results are shown in Table 6.

[0096] [Table 4]

[0097] [Table 5]

[0098] [Table 6]

[0099] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, including combining each technical feature in other appropriate ways, and these simple modifications and combinations should also be considered as the contents disclosed in the present invention, and all fall within the protection scope of the present invention. [Explanation of symbols]

[0100] In Figure 1, 1. Diesel feedstock and hydrogen gas 2. Gas-phase hydrogenation reactor 3. Vapor-phase desulfurization reaction products 4. Pressure booster 5 Liquid Phase Hydrogenation Reactor 6 Liquid phase hydrogenation reaction products 7 Gas Phase Components 8 Heat exchange equipment 9. High-pressure separator 10 Hydrogen gas containing hydrogen sulfide 11 Hydrogenated light components 12 Stripping and fractionation equipment 13 Diesel refined products In Figure 2, 1. Wax oil raw material and hydrogen gas 2. Gas-phase hydrogenation reactor 3. Vapor-phase desulfurization reaction products 4. Pressure booster 5 Liquid Phase Hydrogenation Reactor 6 Liquid phase hydrogenation reaction products 7 Gas Phase Components 8 Heat exchange equipment 9. High-pressure separator 10 Hydrogenated light components 11 Hydrogen gas containing hydrogen sulfide 12 Third hydrogenation reactor 13 Special oil products

Claims

1. A method for hydrogenating a hydrocarbon oil, comprising: Step (1) of subjecting a hydrocarbon oil feedstock to a gas-phase desulfurization reaction in a gas-phase hydrogenation reactor in the presence of hydrogen gas to obtain a gas-phase desulfurization reaction product; (2) pressurizing the vapor-phase desulfurization reaction product to obtain an pressurized stream; (3) sending the pressurized stream to a liquid-phase hydrogenation reactor, and subjecting the liquid-phase components in the pressurized stream to a liquid-phase hydrogenation reaction in the liquid-phase hydrogenation reactor to a liquid-phase hydrogenation reaction product; The conditions for the gas-phase desulfurization reaction include a pressure of 0.5 to 2 MPa, a temperature of 320 to 390°C, a hydrogen / oil volume ratio of 300 to 700, and a space velocity of 0.8 to 2 h-1; The conditions of the liquid phase hydrogenation reaction include a pressure of 3 to 6 MPa, a temperature of 260 to 360°C, and a space velocity of 0.5 to 1 h-1; The pressure of the liquid-phase hydrogenation reaction is at least 2.5 to 6 MPa higher than the pressure of the gas-phase desulfurization; A method for hydrogenating hydrocarbon oils, comprising:

2. the hydrocarbon oil feedstock is at least one selected from low-quality diesel, aviation kerosene, wax oil, and naphtha; The low-quality diesel has an initial boiling point of 150 to 200°C, a final boiling point of 320 to 400°C, an S content of ≦20000 μg / g, an N content of ≦1000 μg / g, and a polycyclic aromatic hydrocarbon content of ≦50 wt%; The aviation kerosene has an initial boiling point of 80 to 150°C, a final boiling point of 200 to 300°C, an S content of ≦8000 μg / g, and an N content of ≦100 μg / g; The method according to claim 1, wherein the wax oil has an initial boiling point of 160 to 220°C, a final boiling point of 300 to 400°C, an S content of ≦30,000 μg / g, an N content of ≦2,000 μg / g, and a polycyclic aromatic hydrocarbon content of ≦60 wt%.

3. 2. The method according to claim 1, wherein the vapor-phase desulfurization reaction is carried out in the presence of a first hydrogenation catalyst, and the first hydrogenation catalyst is a catalyst having a hydrodesulfurization function.

4. The method described in claim 3, wherein the gas phase hydrogenation reactor is a fixed bed reactor.

5. The method according to claim 1, wherein in step (2), the gas-phase desulfurization reaction product is pressurized to 2 to 10 MPa.

6. The method described in claim 5, wherein in step (2), the gas-phase desulfurization reaction product is pressurized to 2.5 to 7.5 MPa.

7. The hydrocarbon oil feedstock is low-quality diesel, and in step (2), the gas-phase desulfurization reaction product is pressurized to 4.5 to 6.5 MPa; 7. The method according to any one of claims 1 to 6, wherein the liquid phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is a hydrodearomatization catalyst.

8. The hydrocarbon oil feedstock is low-quality diesel, and in step (2), the vapor-phase desulfurization reaction product is pressurized to 4 to 7 MPa; 7. The method according to any one of claims 1 to 6, wherein the liquid-phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is an advanced hydrodesulfurization catalyst.

9. The hydrocarbon oil feedstock is aviation kerosene, and in step (2), the gas-phase desulfurization reaction product is pressurized to 2.5 to 4 MPa; 7. The method according to any one of claims 1 to 6, wherein the liquid phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is a hydrodearomatization catalyst.

10. The hydrocarbon oil feedstock is aviation kerosene, and in step (2), the gas-phase desulfurization reaction product is pressurized to 2.5 to 4 MPa; 7. The method according to claim 1, wherein the liquid-phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is a hydroisomerization catalyst.

11. The hydrocarbon oil feedstock is wax oil, and in step (2), the gas-phase desulfurization reaction product is pressurized to 5 to 10 MPa; 7. The process of any one of claims 1 to 6, wherein the liquid phase hydrogenation reaction is carried out in the presence of a second hydrogenation catalyst, and the second hydrogenation catalyst is an isomerization pour point reducing catalyst.

12. The method according to claim 11, further comprising the steps of discharging the gas phase components in the pressurized stream from above out of the liquid phase hydrogenation reactor, optionally subjecting them to a de-impurity treatment to obtain hydrogenated light components, and then mixing the hydrogenated light components with a liquid phase hydrogenation reaction product to carry out a hydrogenation dearomatization reaction.

13. The process according to any one of claims 1 to 6, wherein the liquid phase hydrogenation reactor is a fixed bed reactor.

14. a gas phase component in the pressurized stream is allowed to move upwardly and discharged from the liquid-phase hydrogenation reactor, and optionally subjected to a de-impurity treatment to obtain a hydrogenated light component; The method according to any one of claims 1 to 6, wherein the impurity removal treatment is a dehydrosulfurization treatment.

15. The impurity removal treatment includes heat exchanging the gas phase components, followed by high-pressure separation to obtain the hydrogenated light components and hydrogen sulfide-containing hydrogen gas, The method according to claim 14, wherein the gas phase component is cooled to a temperature of 100 to 200°C by the heat exchange.

16. 15. The method of claim 14, further comprising mixing the liquid-phase hydrogenation reaction product with the hydrogenated light component to obtain a hydrogenated product.

17. The method described in claim 16, wherein the hydrogenated product is a diesel refinery product having a polycyclic aromatic hydrocarbon content of 5 wt% or less and an S content of 10 μg / g or less.

18. The method described in claim 16, wherein the hydrogenated product is an aviation kerosene refined product having a smoke point of 26 mm or more and / or a freezing point of -50°C or less.

19. The method described in claim 16, wherein the hydrogenated product is a specialty oil product having an aromatic hydrocarbon content of 5 wt% or less and an S content of 10 μg / g or less.

20. A hydrocarbon oil hydrogenation system used in the hydrocarbon oil hydrogenation method according to any one of claims 1 to 19, comprising: a gas-phase hydrogenation reactor packed with a first hydrogenation catalyst, a pressure booster, and a liquid-phase hydrogenation reactor packed with a second hydrogenation catalyst, which are connected in series; The gas-phase hydrogenation reactor performs a gas-phase desulfurization reaction between a hydrocarbon oil feedstock and hydrogen gas to obtain a gas-phase desulfurization reaction product, the pressure booster boosts the vapor-phase desulfurization reaction product to obtain a boosted stream; a liquid-phase hydrogenation reactor that brings the pressurized stream into contact with a second hydrogenation catalyst to carry out a liquid-phase hydrogenation reaction and obtain a liquid-phase hydrogenation reaction product;

21. The hydrogenation system according to claim 20, wherein the pressure booster boosts the gas-phase desulfurization reaction product to a pressure of 2 to 10 MPa.

22. the hydrocarbon oil feedstock is diesel, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is a hydrodearomatization catalyst; or the hydrocarbon oil feedstock is diesel, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is an advanced hydrodesulfurization catalyst; or the hydrocarbon oil feedstock is aviation kerosene, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is a hydrodearomatization catalyst; or the hydrocarbon oil feedstock is aviation kerosene, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is a hydroisomerization catalyst; or 21. The hydrogenation system of claim 20, wherein the hydrocarbon oil feedstock is a waxy oil, the first hydrogenation catalyst is a hydrodesulfurization catalyst, and the second hydrogenation catalyst is an isomerization pour point reducing catalyst.

23. the gas-phase hydrogenation reactor is a fixed-bed reactor; The hydrogenation system according to any one of claims 20 to 22, wherein the liquid-phase hydrogenation reactor is a fixed-bed reactor.

24. the method further includes a removal device, the inlet of which is connected to the outlet for the gas phase component of the liquid-phase hydrogenation reactor, and which performs impurity removal treatment on the gas phase component in the pressurized stream discharged from the liquid-phase hydrogenation reactor to obtain a hydrogenated light component; The impurity removal device is a hydrogen sulfide removal device, 23. The hydrogenation system according to any one of claims 20 to 22, wherein the desulfurization unit comprises a heat exchange unit and a high-pressure separation unit in communication therewith.

25. 25. The hydrogenation system of claim 24, further comprising a mixer for receiving and mixing the liquid-phase hydrogenation reaction product and the hydrogenated light components to obtain a hydrogenated product.

26. 25. The hydrogenation system according to claim 24, wherein the hydrocarbon oil feedstock is wax oil, and the system further comprises a third hydrogenation reactor packed with a third hydrogenation catalyst, an inlet of the third hydrogenation reactor being connected to the liquid-phase hydrogenation reaction product outlet of the liquid-phase hydrogenation reactor and the hydrogenated light component outlet of the de-impurity unit, and performing a hydrodearomatization reaction of the hydrogenated light component and the liquid-phase hydrogenation reaction product.

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