A hydrogenation process for blending bio-oil

Abstract

The invention discloses a hydrogenation process for blending bio-oil, comprising: hydrogen enters from a gas-liquid contact zone, partially passes through the gas-liquid contact zone, the gas-liquid countercurrent zone, the gas-liquid separation zone and the gas phase reaction zone in sequence, and partially exchanges heat with the liquid phase material flowing out of the gas-liquid countercurrent zone and is mixed into the liquid phase reaction zone; the raw material for blending bio-oil enters from the gas-liquid separation zone, partially converts into gas phase, enters the gas phase reaction zone together with the gas phase logistics from the gas-liquid countercurrent zone for hydrogenation reaction, and the gas phase reaction product flows out from the top of the reactor; the liquid phase raw material in the gas-liquid separation zone enters the gas-liquid countercurrent zone, contacts with hydrogen countercurrent reaction and enters the gas-liquid contact zone, the liquid phase material enters the gas-liquid contact zone downward for liquid phase hydrogenation reaction, and the liquid phase reaction product flows out from the bottom of the reactor. The invention can effectively control the reaction temperature rise, timely remove the water generated in the reaction process, flexibly produce petroleum products according to actual needs, and extend the operation cycle of the bio-oil hydrogenation device.

Description

Technical Field

[0001] The invention belongs to the field of clean oil refining, and in particular relates to a hydrogenation process for blending bio-oil. Background Art

[0002] Bio-oil refers to higher fatty acid methyl esters made from animal and plant oils, waste oil from the catering industry, and engineered microalgae. It is a clean liquid fuel that can be used to replace petrochemical oils and has very good compatibility with petrochemical oils. Various methods for producing biofuels from vegetable oils have been reported, such as direct mixing, microemulsification, transesterification, and thermal cracking. Compared with fossil diesel, biodiesel has the characteristics of no sulfur, low benzene, low nitrogen, high cetane number (10-15 higher than petrochemical diesel), better combustion performance than petrochemical diesel, good lubricity, and safe storage, making it an ideal substitute for non-renewable energy sources such as oil.

[0003] At present, the most commonly used bio-oil processing method is to produce it through a process route of hydrogenation refining after blending with petrochemical oil products. The main reaction of bio-oil during hydrogenation is hydrodeoxygenation, which means that under high temperature and high pressure, the unsaturated bonds in fatty acids or glycerides are converted into saturated bonds through hydrogenation, and the oxygen is removed to form water, and the fatty acids or glycerides eventually generate saturated alkanes. The hydrodeoxygenation reaction is also accompanied by hydrodecarboxylation or decarbonylation reactions, that is, the oxygen and carbon are removed to form CO2 or CO. The saturated straight-chain alkanes generated by the hydrodeoxygenation reaction are characterized by a high cetane number, but poor low-temperature fluidity. The method of hydroisomerization can be used to reduce the cloud point and condensation point of the product and improve the low-temperature fluidity of the product. Therefore, the main reactions of animal and vegetable oils under high temperature and high pressure are thermal cracking, hydrodeoxygenation, hydrodecarboxylation, hydrodecarbonylation and isomerization.

[0004] However, the processing of animal and vegetable oils is also very difficult, mainly including: the unsaturated substances in animal and vegetable oils are prone to coking at high temperatures; the hydrogenation of animal and vegetable oils is a highly exothermic reaction, which can easily cause the catalyst bed to overheat; the water generated by hydrodeoxygenation has a destructive effect on the catalyst; the acidic gas generated by hydrodecarboxylation increases the difficulty of post-processing, etc.

[0005] CN200810246696.0 discloses a combined hydrogenation method of mineral oil and animal and vegetable oil. This method sets two hydrogenation reaction zones, the first hydrogenation reaction zone processes mineral oil, the gas phase separated from the product enters the second hydrogenation reaction zone together with the animal and vegetable oil, and the gas phase separated from the product of the second hydrogenation reaction zone enters the first hydrogenation reaction zone together with the mineral oil. This method can use the hydrogen sulfide generated during the processing of mineral oil to keep the catalyst in the second hydrogenation reaction zone in a sulfurized state. In the second reaction zone, the generated water can dissolve a certain amount of hydrogen sulfide, so the concentration of hydrogen sulfide entering the first hydrogenation reaction zone can be reduced. However, this method does not solve the problem of large-scale heat release during the processing of bio-oil, and it is difficult to avoid the influence of generated water on the life of the catalyst.

[0006] CN202022586919.7 discloses a hydrogenation reactor for reducing the temperature rise of vegetable oil hydrogenation reaction. The invention sets multiple cold hydrogen injection ports on the side wall of the reactor shell, sets a liquid phase collector in the reactor shell, and circulates a portion of the liquid phase product of the hydrogenation reaction to the raw material inlet through the liquid phase collector, dilutes the oxygen and olefin content in the raw material, and reduces the reaction temperature rise. However, this method still does not solve the impact of reaction generated water on the catalyst life. Summary of the invention

[0007] In view of the problems such as the difficulty in controlling the bed temperature during bio-oil processing and the influence of reaction generated water on the catalyst life, the present invention proposes a hydrogenation process for blending bio-oil. By zoning and setting the fluid flow state and reaction phase state, controlling the reaction conditions and reaction type, the reaction temperature rise can be effectively controlled, the water generated during the reaction process can be removed in time, and the operation cycle of the bio-oil hydrogenation device can be extended; at the same time, the raw materials or products can be flexibly adjusted according to actual production needs.

[0008] The hydrogenation process of the blended bio-oil of the present invention comprises the following contents: the hydrogenation process is carried out in a fixed bed reactor arranged in partitions, wherein the reactor is sequentially provided with a gas phase reaction zone, a gas-liquid separation zone, a gas-liquid countercurrent zone, a gas-liquid contact zone and a liquid phase reaction zone from top to bottom;

[0009] The hydrogen enters from the gas-liquid contact zone, part of it passes through the gas-liquid contact zone, gas-liquid countercurrent zone, gas-liquid separation zone and gas phase reaction zone in sequence, and part of it exchanges heat with the liquid phase material flowing out of the gas-liquid countercurrent zone and mixes into the liquid phase reaction zone;

[0010] The raw materials blended with bio-oil enter from the gas-liquid separation zone, and under certain conditions, part of the raw materials are converted into gas-phase raw materials, and enter the gas-phase reaction zone together with the gas-phase flow from the gas-liquid countercurrent zone for hydrogenation, deolefination and desulfurization reactions, and the gas-phase reaction products flow out from the top of the reactor;

[0011] The unconverted liquid raw material in the gas-liquid separation zone flows downward into the gas-liquid countercurrent zone, and reacts with the hydrogen from the gas-liquid contact zone in a countercurrent contact manner. The gaseous material after the reaction continues to flow upward into the gas-liquid contact zone, and the liquid material flows downward into the gas-liquid contact zone, and after mixing with hydrogen, enters the liquid phase reaction zone; a liquid phase hydrogenation reaction is carried out in the liquid phase reaction zone, and the liquid phase reaction product flows out from the bottom of the reactor;

[0012] The gas phase reaction product and the liquid phase reaction product are mixed and fractionated to obtain naphtha, jet fuel component and vehicle diesel component.

[0013] In the process of the present invention, the raw material for blending bio-oil is a mixed oil of mineral oil and bio-oil, wherein the mineral oil contains at least diesel fraction, the diesel fraction is ≮30%, preferably ≮50%, and the mineral oil may also contain jet fuel and / or gasoline fraction. It can be a straight run fraction, or it can be a secondary processed oil such as catalytic cracking, delayed coking, catalytic cracking, fixed bed residue oil hydrogenation, etc.; sulfur content ≯15000μg / g, nitrogen content ≯2000μg / g, aromatic content ≯70%; bio-oil can be different types of animal and plant oils, such as microalgae oil, restaurant waste oil, acidified oil, and coconut oil, palm oil, soybean oil, rapeseed oil, black tar oil and other types of vegetable oils; oxygen content ≯20%, sulfur content ≯100μg / g, nitrogen content ≯100μg / g, density ≯1000kg / m 3 The mass ratio of bio-oil to the raw material is ≯50%, preferably 15% to 40%.

[0014] In the process of the present invention, the gas-liquid separation zone is used to convert the light olefin-rich components in the feedstock into gas phase and enter the gas phase reaction zone, and the unconverted components enter the gas-liquid countercurrent zone in liquid phase.

[0015] The operating conditions of the gas-liquid separation zone are: pressure 1.0~8.0MPa, preferably 2.0~6.0MPa, wherein the hydrogen partial pressure accounts for 45%~80% of the total pressure; feed temperature 80~200℃, preferably 140~180℃.

[0016] In the process of the present invention, the gas phase reaction zone is used for low-temperature deolefination and small molecular sulfur removal reaction of the gas phase raw material from the gas-liquid separation zone; the reaction zone is filled with a light distillate oil hydrogenation catalyst with low-temperature hydrogenation activity, the active metal is a VIB group metal oxide or / and a VIII group metal oxide, the carrier is alumina or an auxiliary modified alumina, based on the weight of the hydrogenation deolefination catalyst, the VIB group metal oxide content is 5%-30%, preferably 5%-15%, the VIII group metal oxide content is 1%-15%, preferably 2%-6%; the specific surface area is 100-500m 2 / g, preferably 300-500m 2 / g, pore volume is 0.3-1.2mL / g, preferably 0.4-0.8mL / g. Based on the total catalyst loading in the reactor, the catalyst loading volume ratio in the gas phase reaction zone is 1%~50%, preferably 5%~35%; the operating conditions of the gas phase reaction zone are: pressure 0.1~6.0MPa, preferably 0.5~3.0MPa, where the hydrogen partial pressure accounts for 40%~70% of the total pressure; volume space velocity 0.1~6.0h -1 , preferably 0.5~3.0h -1 ; The reaction temperature is 80~200℃, preferably 120~160℃.

[0017] In the process of the present invention, the gas-liquid countercurrent zone is used for hydrogenation reaction of the unconverted liquid phase raw material in the gas-liquid separation zone, mainly including the removal of sulfur, nitrogen, aromatics in the raw material and the removal of oxygen in the bio-oil. The gas-liquid countercurrent zone is filled with a diesel hydrorefining catalyst, which is well known to those skilled in the art. The active metal is a metal oxide of Group VIB or / and a metal oxide of Group VIII. Based on the weight of the hydrogenation catalyst, the content of the metal oxide of Group VIB is 5%-30%, preferably 15%-25%, and the content of the metal oxide of Group VIII is 1%-15%, preferably 3%-8%; the carrier is alumina or an auxiliary modified alumina, and the auxiliary is one or more of B, P, Mg, Zr or Si. Based on the weight of the carrier, the auxiliary is 3%-15% in terms of oxide, preferably 3%-10%. If it is necessary to increase the production of jet fuel or naphtha, a hydrocracking catalyst can be loaded, generally with W-Ni as the catalyst active metal, Al2O3 as the carrier, and a metal loading of 20wt%~35wt%. Commercially available products can be used or prepared according to existing methods. The operating conditions of the gas-liquid countercurrent zone are generally: pressure 1.0~10.0MPa, preferably 4.0~8.0MPa, where the hydrogen partial pressure accounts for 50%~90% of the total pressure; volume space velocity 0.1~10.0h -1 , preferably 0.5~5.0h -1 ; Reaction temperature 200~400℃, preferably 260~370℃.

[0018] In the process of the present invention, the gas-liquid contact zone is used for contact heat exchange and mass transfer between hydrogen and liquid phase materials in the gas-liquid countercurrent zone. The operating conditions of the gas-liquid contact zone are pressure 3.0-10.0 MPa, preferably 5.0-8.0 MPa, wherein the hydrogen partial pressure accounts for 100% of the total pressure; the feed temperature is 50-300°C, preferably 150-200°C at the initial start-up. After the device runs smoothly, the feed can be switched to normal temperature.

[0019] In the process of the present invention, the liquid phase reaction zone is used for isomerization reaction of the liquid phase material flowing out of the gas-liquid countercurrent zone, mainly including the hydrogenation isomerization reaction of alkanes in bio-oil and mineral oil. The liquid phase reaction zone is loaded with a hydrogenation isomerization catalyst, which is well known to those skilled in the art. The catalyst comprises a carrier, a hydrogenation active metal and a molecular sieve; wherein the carrier is an inorganic refractory oxide, generally selected from one or more of alumina, amorphous silica-alumina, silicon dioxide or titanium oxide; the hydrogenation active metal comprises a metal component of Group VIB and / or Group VIII, wherein Group VIB is selected from tungsten and / or molybdenum, and the content is 5% to 35% as oxide, preferably 10% to 30%, and Group VIII is selected from nickel and / or cobalt, and the content is 5% to 35% as oxide, preferably 10% to 25%, and the molecular sieve comprises at least one large-pore molecular sieve, and preferably, the large-pore molecular sieve is selected from at least one of β molecular sieve, USY, Y, ZSM-3, ZSM-20, MCM-68, SAP-5, SAP-37 and mordenite. The operating conditions of the liquid phase reaction zone are generally: pressure 1.0~8.0MPa, preferably 3.0~7.0MPa, this is a pure liquid phase reaction zone, the volume ratio of standard hydrogen to oil is 2~50, preferably 10~30; volume space velocity 0.1~6.0h -1 , preferably 0.5~3.0h -1 The reaction temperature is 260-400°C, preferably 300-360°C. The catalyst loading volume ratio in the liquid phase reaction zone is 1%-80%, preferably 30%-60%.

[0020] In the process of the present invention, hydrogen and raw materials are fed at medium temperature (generally 150°C~200°C) of the heating furnace when the operation is started. After the bed layer shows a significant temperature rise, the heating furnace is stopped and hydrogen and raw materials are fed at room temperature (generally 5°C~30°C).

[0021] In the process of the present invention, the gas phase reaction product is mixed with the liquid phase product and then enters the subsequent stripping and fractionation process to obtain qualified chemical raw materials, aviation kerosene, diesel and other products. For example, when the increase in the production of naphtha or aviation kerosene is used as the scheme, coconut oil, palm oil, tar oil and the like are generally used as bio-oil raw materials, light distillate oil hydrogenation catalyst, diesel hydrocracking catalyst and isomerization catalyst are used as the gradation system, naphtha / jet kerosene products flow out from the top of the reactor, and diesel blending components flow out from the bottom; when the production of diesel is used as the scheme, soybean oil, rapeseed oil, microalgae oil and the like are generally used as bio-oil raw materials, light distillate oil hydrogenation catalyst, diesel hydrogenation catalyst and isomerization catalyst are used as the gradation system, and the effluents from the top and bottom of the reactor are mixed as diesel products.

[0022] The process method of the present invention aims at the problem of difficult bio-oil processing and designs a low-energy consumption and low-cost process line, which can meet the processing of inferior oil products. The specific advantages are as follows:

[0023] The present invention realizes a high degree of coupling of the reactant flows in each partition through the partition setting and the raw material feeding method; in particular, the coordinated cooperation of the gas phase reaction zone, the gas-liquid countercurrent zone and the liquid phase reaction zone can better distribute and balance the heat of the three reaction zones and realize coupling. First, the olefin substances in the raw materials are enriched in the gas phase reaction zone for a separate reaction to avoid the simultaneous violent heat release of the olefin hydrogenation and hydrodeoxygenation reactions; the hydrodeoxygenation reaction mainly occurs in the gas-liquid countercurrent zone, which is also the reactor with the most obvious concentrated heat release. Through the reverse flow of the gas phase and the liquid phase in this area, a large amount of reaction heat can be quickly carried to the gas phase reaction zone and the liquid phase reaction zone, which not only meets the reaction temperature requirements of the two reaction zones, but also realizes better control of the catalyst bed temperature in the gas-liquid countercurrent zone, delays the coking and deactivation of the catalyst surface, avoids pressure drop and prolongs the service life of the catalyst.

[0024] The hydrogen entering from the gas-liquid contact zone exchanges mass and heat with the liquid material, and most of it goes uphill, promptly removing H2S, NH3, and H2O from the catalyst surface, which is beneficial to the depth of the hydrogenation reaction in each reaction zone, while also avoiding the influence of water generated during the reaction on the activity and strength of the catalyst.

[0025] The effluent from the gas-liquid countercurrent zone contacts pure hydrogen in the gas-liquid contact zone, undergoes heat exchange and cooling, and quickly enters the liquid phase reaction zone below. Since the upward hydrogen takes away the generated gas phase light hydrocarbons in time, the downward liquid phase contains almost no low molecular hydrocarbons and hydrogen sulfide, which is conducive to increasing the mixing and dispersion of hydrogen in the liquid phase, further promoting the hydrogenation reaction. The hydrogen escape after entering the reactor during the hydrogen mixing process of the conventional liquid phase hydrogenation process is avoided. At the same time, the liquid phase reaction zone below is a liquid phase space, which can well control the logistics state of the reactor outlet. If there is no such area, it will cause the problem of hydrogen being carried out of the reactor without reacting through the catalyst bed, which can save the high-pressure separator in the conventional process flow and simplify the process.

[0026] At the same time, the coupling effect of the three reaction zones set in the present invention can make the reaction system more stable. While the gas-liquid reverse contact in the gas-liquid countercurrent zone strengthens the mass transfer process, it is accompanied by backmixing, which requires stable pressure control. The uppermost gas phase reaction zone has a large compressible gas phase space, which has a good buffering effect on stabilizing the bed pressure and stabilizing the fluid flow state. By flexibly controlling the outlet gas volume, the gas phase flow rate and liquid layer thickness in the gas-liquid countercurrent zone can be adjusted, thereby increasing the gas velocity range for liquid flooding. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 . Schematic diagram of the hydrogenation process of the blended bio-oil used in the example.

[0028] In the figure: 1-raw material, 2-hydrogen, 3-gas phase reaction zone, 4-gas-liquid separation zone, 5-gas-liquid countercurrent zone, 6-gas-liquid mixing zone, 7-liquid phase reaction zone, 8-gas phase reaction product, 9-liquid phase reaction product. DETAILED DESCRIPTION

[0029] by Figure 1 The implementation process of the hydrogenation process of the blended bio-oil of the present invention is described as follows: the feedstock 1 enters the hydrogenation reactor from the gas-liquid separation zone 4. The gas-liquid separation zone 4 separates the feedstock into a gas phase and a liquid phase. The gas phase flows upward into the gas phase reaction zone 3, and the liquid phase flows downward into the gas-liquid countercurrent zone 5. The hydrogen 2 enters the hydrogenation reactor in the gas-liquid mixing zone 6, and after mixing and contacting with the liquid phase material flowing downward from the gas-liquid countercurrent zone 5, the hydrogen 2 flows upward into the gas-liquid countercurrent zone 5, and the liquid phase material carrying the hydrogen flows downward into the liquid phase reaction zone 7.

[0030] Gas phase reaction occurs in gas phase reaction zone 3, mainly saturation of olefins in light components and removal of small molecular sulfur in petroleum, generating gas phase reaction zone effluent 8. Gas-liquid two-phase reaction occurs in gas-liquid countercurrent zone 5, the liquid phase flows downward, the gas phase is hydrogen flows upward, gas-liquid reverse contact occurs petroleum desulfurization, denitrogenation, aromatic saturation reaction and bio-oil hydrodeoxygenation reaction, if the light oil yield is sought, then the hydrocracking catalyst is loaded, and hydrocracking reaction occurs on the basis of hydrofining. The liquid phase flow after the reaction in gas-liquid countercurrent zone 5 flows downward into gas-liquid contact zone 6, and after contacting with hydrogen for heat exchange and mass transfer, enters liquid phase reaction zone 7, where liquid phase reaction occurs, mainly alkanes hydroisomerization reaction occurs, and liquid phase reaction zone effluent 9 is obtained. After the gas phase reaction zone effluent 8 and the liquid phase reaction zone effluent 9 are mixed, they enter the subsequent stripping fractionation system together.

[0031] Embodiment 1~3

[0032] exist Figure 1 In the process flow, a 100mL fixed bed hydrogenation reactor is set. The 100mL fixed bed hydrogenation reactor is provided with a catalyst bed layer in the gas phase reaction zone, the gas-liquid countercurrent zone, and the liquid phase reaction zone from top to bottom. 20mL of light distillate oil hydrogenation catalyst A is loaded in the gas phase reaction zone, 50mL of diesel hydrogenation catalyst B is loaded in the gas-liquid countercurrent zone, and 30mL of hydrogenation isomerization catalyst C is loaded in the liquid phase reaction zone. A mixed oil of straight-run diesel and soybean oil is used as the raw material, of which the mass of bio-oil accounts for 40%, and the product is a blending component for automotive diesel. The properties of the catalyst are shown in Table 1, the properties of the feedstock oil are shown in Table 2, and the reaction process conditions and results are shown in Table 3.

[0033] Example 4

[0034] exist Figure 1In the process flow, a 100mL fixed bed hydrogenation reactor is set. The 100mL fixed bed hydrogenation reactor is provided with a catalyst bed layer in the gas phase reaction zone, the gas-liquid countercurrent zone, and the liquid phase reaction zone from top to bottom. 20mL of light distillate oil hydrogenation catalyst A is loaded in the gas phase reaction zone, 50mL of diesel hydrocracking catalyst D is loaded in the gas-liquid countercurrent zone, and 30mL of hydrogenation isomerization catalyst C is loaded in the liquid phase reaction zone. A mixed oil of straight-run diesel and soybean oil is used as the raw material, of which the mass of bio-oil accounts for 40%, and the products are automotive diesel blending components and jet fuel. The properties of the catalyst are shown in Table 1, the properties of the feedstock oil are shown in Table 2, and the reaction process conditions and results are shown in Table 3.

[0035] Comparative Example 1

[0036] A conventional fixed bed hydrogenation process was adopted, and reactor 1 and reactor 2 were respectively set in the process flow. Reactor 1 was filled with 20 mL of light distillate oil hydrogenation catalyst A and 50 mL of diesel hydrogenation catalyst B, and reactor 2 was filled with 30 mL of hydrogenation isomerization catalyst C. The properties of the raw materials were the same as those in Example 1, the reaction conditions in reactor 1 were the same as those in the gas-liquid countercurrent zone in Example 3, and the reaction conditions in reactor 2 were the same as those in the liquid phase reaction zone in Example 3.

[0037] Comparative Example 2

[0038] Two oil products were hydrogenated separately. Bio-oil was hydrogenated to remove olefins and deoxygenate in reactor 1, and 5 mL of light distillate oil hydrogenation catalyst A and 15 mL of diesel hydrogenation catalyst B were loaded in reactor 1. Reactor 2 was isomerized and 20 mL of hydrogenation isomerization catalyst C was loaded. Mineral oil was desulfurized, denitrogenated and dearomatized in hydrogenation reactor 3, and 40 mL of diesel hydrogenation catalyst B was loaded. The conditions of reactor 1 were the same as those of the gas-liquid countercurrent zone of Example 3, the conditions of reactor 2 were the same as those of the liquid phase reaction zone of Example 3, and the conditions of reactor 3 were the same as those of the gas-liquid countercurrent zone of Example 3. Both oil products needed to be heated to the required reaction temperature using a heating furnace before processing. The properties of the raw materials were the same as those in the example.

[0039] Comparative Example 3

[0040] Two fixed bed reactors are connected in series. Reactor 1 is provided with a gas phase reaction zone, a gas-liquid separation zone and a gas-liquid countercurrent zone from top to bottom. The raw material enters reactor 1 from the gas-liquid separation zone, and hydrogen enters the reactor from the bottom of reactor 1. 20 mL of light distillate oil hydrogenation catalyst A is filled in the gas phase reaction zone, and 50 mL of diesel hydrogenation catalyst B is filled in the gas-liquid countercurrent zone; the effluent of reactor 1 enters reactor 2 in a liquid phase state, and a liquid phase reaction zone is provided in reactor 2, and 30 mL of hydrogenation isomerization catalyst C is filled in the liquid phase reaction zone.

[0041] Table 1 Raw oil properties

[0042]

[0043] Table 2 Catalyst properties

[0044]

[0045] Table 3 Process conditions and results

[0046]

[0047] The evaluation results in Table 3 can illustrate that the hydrogenation process of the bio-oil blended with the present invention can better partition the raw materials for reaction, and utilize the gas-liquid countercurrent and hydrogen stripping effect to control the reaction temperature rise, and remove the generated water in time, while obtaining better reaction effect, prolong the service life of the catalyst. And better control and utilize the reaction heat, simple process, energy saving and consumption reduction. When the conventional fixed bed diesel hydrogenation process is used to process the mixed raw materials blended with bio-oil, the temperature in the reactor is difficult to control, resulting in rapid deactivation of the main catalyst, and it is difficult for the refined product to meet the standards. Using bio-oil and petroleum hydrogenation processes separately, both process flows need to be equipped with a separate heating furnace, the energy consumption is high, the reaction heat of the bio-oil hydrogenation process cannot be fully utilized, and the problem of saturated concentrated heat release of olefins and oxygen-containing substances is difficult to solve, and there is still a defect of short operation cycle. Compared with Comparative Example 3, if the liquid phase reaction zone is separated from the reaction system, when hydrogen enters from the bottom of the reactor 1, the hydrogen is easily directly taken out of the reactor by the bottom effluent, resulting in poor reaction effect.

Claims

1. A hydrogenation process for blending bio-oil, characterized in that The invention includes the following contents: the hydrogenation process is carried out in a fixed bed reactor arranged in zones, and the reactor is composed of a gas phase reaction zone, a gas-liquid separation zone, a gas-liquid countercurrent zone, a gas-liquid contact zone and a liquid phase reaction zone from top to bottom; The hydrogen enters from the gas-liquid contact zone, part of it passes through the gas-liquid contact zone, gas-liquid countercurrent zone, gas-liquid separation zone and gas phase reaction zone in sequence, and part of it exchanges heat with the liquid phase material flowing out of the gas-liquid countercurrent zone and mixes into the liquid phase reaction zone; The raw materials blended with bio-oil enter from the gas-liquid separation zone, and under certain conditions, part of the raw materials are converted into gas-phase raw materials, and enter the gas-phase reaction zone together with the gas-phase flow from the gas-liquid countercurrent zone for hydrogenation, deolefination and desulfurization reactions, and the gas-phase reaction products flow out from the top of the reactor; The unconverted liquid raw material in the gas-liquid separation zone flows downward into the gas-liquid countercurrent zone, and reacts with the hydrogen from the gas-liquid contact zone in a countercurrent manner. The gaseous phase flow after the reaction continues to flow upward into the gas-liquid contact zone, and the liquid phase material flows downward into the gas-liquid contact zone, and after mixing with hydrogen, enters the liquid phase reaction zone; A liquid phase hydrogenation reaction is carried out in the liquid phase reaction zone, and the liquid phase reaction product flows out from the bottom of the reactor; The gas phase reaction product and the liquid phase reaction product are mixed and fractionated to obtain naphtha, jet fuel component and vehicle diesel component; the raw material for blending bio-oil is a mixed oil of mineral oil and bio-oil, wherein the mineral oil contains at least a diesel fraction, and the diesel fraction is ≮30wt%; the bio-oil is animal and plant oil, with an oxygen content of ≯20%, a sulfur content of ≯100μg / g, a nitrogen content of ≯100μg / g, and a density of ≯1000kg / m 3 ; The mass proportion of bio-oil in raw materials is ≯50%; The gas-liquid separation zone is used to convert the light components rich in olefins in the raw materials into gas phase and enter the gas phase reaction zone, and the unconverted components enter the gas-liquid countercurrent zone in liquid phase; the operating conditions of the gas-liquid separation zone are: pressure 1.0~8.0MPa, wherein the hydrogen partial pressure accounts for 45%~80% of the total pressure; the feed temperature is 80~200℃.

2. The hydrogenation process according to claim 1, characterized in that: The mineral oil also contains aviation kerosene and / or gasoline fractions.

3. The hydrogenation process according to claim 1, characterized in that: The sulfur content of the mineral oil is ≯15000 μg / g, the nitrogen content is ≯2000 μg / g, and the aromatic content is ≯70%.

4. The hydrogenation process according to claim 1, characterized in that: The gas phase reaction zone is used for low temperature deolefination and small molecular sulfur removal reaction of the gas phase raw material from the gas-liquid separation zone; the reaction zone is filled with a light distillate oil hydrogenation catalyst with low temperature hydrogenation activity, the active metal is a VIB group metal oxide or / and a VIII group metal oxide, the carrier is alumina or an auxiliary modified alumina, based on the weight of the hydrogenation deolefination catalyst, the VIB group metal oxide content is 5%-30%, the VIII group metal oxide content is 1%-15%; the specific surface area is 100-500m 2 / g, pore volume is 0.3-1.2mL / g; based on the total catalyst loading in the reactor, the catalyst loading volume ratio in the gas phase reaction zone is 1%~50%; the operating conditions of the gas phase reaction zone are: pressure 0.1~6.0MPa, of which the hydrogen partial pressure accounts for 40%~70% of the total pressure; volume space velocity 0.1~6.0h -1 ; Reaction temperature 80~200℃.

5. The hydrogenation process according to claim 1, characterized in that: The gas-liquid countercurrent zone is used for hydrogenation reaction of the unconverted liquid raw material in the gas-liquid separation zone; the gas-liquid countercurrent zone is filled with diesel hydrorefining catalyst, the active metal is VIB group metal oxide or / and VIII group metal oxide, based on the weight of the hydrogenation catalyst, the VIB group metal oxide content is 5%-30%, and the VIII group metal oxide content is 1%-15%; the carrier is alumina or additive-modified alumina, the additive is one or more of B, P, Mg, Zr or Si, based on the weight of the carrier, the additive is 3%-15% in terms of oxide; the operating conditions of the gas-liquid countercurrent zone are: pressure 1.0~10.0MPa, wherein the hydrogen partial pressure accounts for 50%~90% of the total pressure; volume space velocity 0.1~10.0h -1 ; Reaction temperature 200~400℃.

6. The hydrogenation process according to claim 1, characterized in that: The gas-liquid countercurrent zone is filled with a hydrocracking catalyst to increase the production of jet fuel or naphtha. The hydrocracking catalyst uses W-Ni as the catalyst active metal, Al2O3 as the carrier, and the metal loading is 20wt%~35wt%.

7. The hydrogenation process according to claim 1, characterized in that: The gas-liquid contact zone is used for contact heat exchange and mass transfer between hydrogen and liquid materials in the gas-liquid countercurrent zone. The operating conditions of the gas-liquid contact zone are pressure 3.0~10.0MPa, in which the hydrogen partial pressure accounts for 100% of the total pressure; the feed temperature is 50~300℃ at the initial start-up, and after the device runs smoothly, switch to normal temperature feed.

8. The hydrogenation process according to claim 1, characterized in that: The liquid phase reaction zone is used for isomerization reaction of liquid phase materials flowing out of the gas-liquid countercurrent zone; the liquid phase reaction zone is filled with a hydrogenation isomerization catalyst; the catalyst comprises a carrier, a hydrogenation active metal and a molecular sieve; wherein the carrier is an inorganic refractory oxide selected from one or more of alumina, amorphous silicon aluminum, silicon dioxide or titanium oxide; the hydrogenation active metal comprises a metal component of Group VIB and / or Group VIII, wherein Group VIB is selected from tungsten and / or molybdenum, 5% to 35% in terms of oxide, and Group VIII is selected from nickel and / or cobalt, 5% to 35% in terms of oxide; the molecular sieve comprises at least one large-pore molecular sieve, and the molecular sieve is selected from at least one of β molecular sieve, Y, ZSM-3, ZSM-20, MCM-68, SAP-5, SAP-37 and mordenite; the operating conditions of the liquid phase reaction zone are: pressure 1.0~8.0MPa, which is a pure liquid phase reaction zone, the volume ratio of standard hydrogen to oil is 2~50; the volume space velocity is 0.1~6.0h -1 ; Reaction temperature 260~400℃.

9. The hydrogenation process according to claim 1, characterized in that: When starting up, hydrogen and raw materials are fed at a temperature of 150~200℃ in the heating furnace. After a significant temperature rise in the bed layer occurs, the heating furnace is stopped and hydrogen and raw materials are fed at a room temperature of 5~30℃.

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