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METHOD FOR PREPARING HIGH-QUALITY FUEL OIL AND/OR CHEMICAL RAW MATERIAL FROM BIOMASS PYROLYSIS LIQUID

20230092425 · 2023-03-23

    Inventors

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    International classification

    Abstract

    A method for preparing a high-quality fuel oil and/or chemical raw material from a biomass pyrolysis liquid. In the method, a biomass pyrolysis liquid undergoes a hydrodeoxygenation reaction in a catalyst full mixing flow circulation system in a fluidized bed reactor to obtain deoxygenated oil, and the obtained deoxygenated oil undergoes a hydrocracking reaction in a fixed bed reactor to obtain high-quality fuel oil and/or a chemical raw material. The method may prevent the condensation and coking of a biomass pyrolysis liquid, solve the problem of rapid catalyst deactivation, and may convert a biomass pyrolysis liquid into a high-quality fuel oil that may be directly used by vehicles and into a chemical product.

    Claims

    1. A method for preparing a high-quality fuel oil and/or chemical raw material from a biomass pyrolysis liquid, comprising the following steps: A) subjecting the biomass pyrolysis liquid to hydrodeoxygenation reaction in a completely mixed flow catalyst circulation system in a fluidized bed reactor to obtain a deoxygenated oil; and B) subjecting the deoxygenated oil from step A) to hydrocracking reaction in a fixed bed reactor to obtain a high-quality fuel oil and/or chemical raw material.

    2. The method of claim 1, wherein the biomass pyrolysis liquid is mixed with a hydrogen donor before entering the fluidized bed reactor, and then enters the reactor at room temperature to 80° C. under the protection of the hydrogen donor.

    3. The method of claim 2, wherein the deoxygenated oil from step A) is divided into two portions, wherein one portion of the deoxygenated oil, used as a circulating oil, is mixed with hydrogen and then returns to the fluidized bed reactor from a bottom of the reactor, and the other portion of the deoxygenated oil is mixed with hydrogen, and then enters the fixed bed reactor for hydrocracking reaction.

    4. The method of claim 3, wherein the other portion of the deoxygenated oil is blended with at least one of heavy diesel, wax oil and coal tar before entering the fixed bed reactor for hydrocracking reaction.

    5. The method of claim 3, wherein the hydrodeoxygenation reaction employs a temperature of 200° C.-400° C., a pressure of 10-20 MPa, a reaction volume space velocity of 0.6-2.0 h.sup.−1, a hydrogen-to-oil ratio of 400:1-1000:1, a circulation ratio of 1: 4-4:1, and a mass ratio of the hydrogen donor to the biomass pyrolysis liquid of 0.2:1-4:1; and the hydrocracking reaction employs a temperature of 150° C.-420° C., a pressure of 12-20 MPa, a reaction volume space velocity of 1.0-4.0 h.sup.−1, and a hydrogen-to-oil ratio of 400:1-1200:1.

    6. The method of claim 2, wherein the biomass hydrolysis liquid enters the reactor at room temperature to 50° C.

    7. The method of claim 2, wherein the hydrogen donor is at least one of hydrocarbon substances obtained by hydrocracking, petroleum hydrocarbon substances, hydrocarbon substances obtained by hydroprocessing coal tar, and hydrocarbon substances obtained by hydrodeoxygenation of organics, wherein the hydrocarbon substances have a boiling point in the range of 160-260° C.

    8. The method of claim 4, wherein the hydrodeoxygenation reaction employs a temperature of 200° C.-400° C., a pressure of 10-20 MPa, a reaction volume space velocity of 0.6-2.0 h.sup.−1, a hydrogen-to-oil ratio of 400:1-1000:1, a circulation ratio of 1: 4-4:1, and a mass ratio of the hydrogen donor to the biomass pyrolysis liquid of 0.2:1-4:1; and the hydrocracking reaction employs a temperature of 150° C.-420° C., a pressure of 12-20 MPa, a reaction volume space velocity of 1.0-4.0 h.sup.−1, and a hydrogen-to-oil ratio of 400:1-1200:1.

    9. The method of claim 1, wherein the completely mixed flow catalyst circulation means that the macroscopic movement of catalyst particles is manifested as a movement in the form of fluidization from a bottom of the reactor to a material level in the reactor, and then back to the bottom of the reactor.

    10. The method of claim 1, wherein the completely mixed flow catalyst circulation system is formed under a combined action of the biomass pyrolysis liquid, a hydrogen donor, a circulating oil, hydrogen, a catalyst, a hydrodeoxygenation product and an internal component.

    11. The method of claim 1, wherein the completely mixed flow catalyst circulation system is formed under a combined action of the following three factors: a fluidization kinetic energy provided by the circulating oil and hydrogen drives the catalyst into a fluidized state; a high-speed disturbance of the fluidized catalyst and a mixture of the circulating oil and hydrogen promotes rapid mixing and dilution of the biomass pyrolysis liquid and the hydrogen donor; and the internal component of the fluidized bed reactor acts to direct, split and swirl a gas-liquid-solid three-phase mixture.

    12. The method of claim 1, wherein a catalyst from the completely mixed flow catalyst circulation system is a spherical catalyst.

    13. The method of claim 1, wherein the biomass pyrolysis liquid includes a liquid substance derived from various biomass species by slow pyrolysis, fast pyrolysis, flash pyrolysis, carbonization or gasification processes.

    14. The method of claim 1, wherein the catalyst is a Group VIII metal alone or a Group VIII metal with one or two of Group IVB, Group VB, Group VIB, Group VIIB, Group IB, and Group IIB metals added as an active component supported on activated carbon or porous carbon, or a catalyst formed from a metal oxide with a carbonized surface.

    15. The method of claim 1, wherein after the catalyst is discharged from the bottom of the fluidized bed reactor, it is regenerated by washing with an alcohol, hydrocarbon or tetrahydrofuran solvent to restore activity.

    16. The method of claim 1, wherein the fluidized bed reactor adopts a single-stage form, or a form of two stages or multiple stages in series; wherein the fixed-bed reactor adopts a single-stage form, or a form of two stages or multiple stages in series.

    Description

    DESCRIPTION OF THE DRAWINGS

    [0053] FIG. 1 is a schematic view showing a process flow diagram of the method for preparing high-quality fuel oils and chemical raw materials according to the present disclosure;

    [0054] FIG. 2 is a GCMS analysis chart of a biomass pyrolysis liquid;

    [0055] FIG. 3 is a GCMS analysis chart of a deoxygenated oil;

    [0056] FIG. 4 shows the molecular weight distribution map of a high-quality fuel oil and a dry biomass pyrolysis liquid, gasoline and diesel;

    [0057] FIG. 5 is a schematic view showing a process flow diagram of a method for co-refining a biomass pyrolysis liquid with heavy diesel, wax oil and coal tar to prepare high-quality fuel oils and chemical raw materials.

    DETAILED DESCRIPTION

    [0058] The present disclosure will be further illustrated with reference to the accompanying drawings and the following Examples.

    EXAMPLE 1

    [0059] As shown by FIG. 1, a biomass pyrolysis liquid 1 entrapped and protected by a hydrogen donor 2 was fed directly to the reaction bed zone of a single-stage fluidized bed hydrodeoxygenation reactor 3 at room temperature. The mass ratio of the biomass pyrolysis liquid to the hydrogen donor was 1:0.5. The hydrogen donor was a petroleum hydrocarbon substance having a boiling point of 200-240° C. Circulating hydrogen 7 and a gaseous substance 29 from the hydrocracking reaction were pressurized by a circulating hydrogen compressor 8 to form a mixed gas 9. The mixed gas 9 was mixed with a circulating oil 18 and heated by a heating furnace 10 to form a gas-liquid mixture 4. The gas-liquid mixture 4 entered the fluidized bed hydrodeoxygenation reactor 3 from the bottom thereof and provided kinetic energy for fluidization in the hydrodeoxygenation reaction. The temperature of the hydrodeoxygenation reaction was controlled at 280° C. by adjusting the temperature of the gas-liquid mixture 4. The biomass pyrolysis liquid was heated, mixed and diluted rapidly under the high-speed disturbance of the completely mixed flow circulating catalyst and the mixture of the circulating oil and hydrogen, and underwent the hydrodeoxygenation reaction. After the reaction effluent 5 was separated by a cold high-pressure gas-liquid separator 6, a portion of the gaseous substance was recycled as circulating hydrogen 7 back to the hydrodeoxygenation reactor, and the other portion of the gaseous substance was purified by a hydrogen purification facility 11. The regenerated hydrogen 20 was combined into fresh hydrogen 21, and then entered the hydrocracking reactor. After the liquid substance 12 flowing out of the cold high pressure separator was further separated by an oil-water separator 13, the aqueous phase substance 14 entered a water treatment facility 15. The deoxygenated oil 16 was pressurized by a circulating pump 17. A portion of the pressurized deoxygenated oil returned to the hydrodeoxygenation reactor as the circulating oil 18, and the other portion of the deoxygenated oil 19 entered a hydrocracking reactor.

    [0060] The fluidization state of the hydrodeoxygenation reaction catalyst was controlled by controlling the amount of the circulating oil 18, so as to meet the operating range of the fluidized bed reactor. The weight ratio of the circulating oil to the biomass pyrolysis liquid was 4:1 in this Example.

    [0061] The hydrogen-to-oil ratio in the hydrodeoxygenation reaction was controlled by controlling the amount of circulating hydrogen. In this Example, the hydrogen-to-oil ratio by volume was 500:1. If the hydrogen-to-oil ratio was too low, the reaction would be incomplete, and polymerization and coking would occur. If the hydrogen-to-oil ratio was too high, the energy consumption would be increased, and at the same time, three-phase separation in the fluidized bed reactor would be rendered difficult (beyond the operating range of the fluidized bed reactor).

    [0062] Compared with a strip-shaped catalyst, the high-strength and high-wear-resistance microspherical catalyst according to the present disclosure had the following advantage in a completely mixed flow circulation system: the polymerization and coking phenomenon caused by excessively high local temperature in the strongly exothermic hydrodeoxygenation reaction was avoided. The rotation and slight friction of the catalyst particles had a self-cleaning effect on the polymer on the outer surface of the catalyst, thereby preventing the polymer from further agglomerating and causing deactivation of the catalyst. Pd/C (palladium supported on a carbon-based material) was used as the hydrodeoxygenation catalyst in this Example.

    [0063] The liquid hourly volume space velocity in this Example was 1.2h.sup.−1, and the reaction pressure was 13.0 MPa.

    [0064] The biomass pyrolysis liquid used in this Example was a liquid product obtained by rapid pyrolysis of pine wood chips. After the hydrodeoxygenation reaction in this Example ran for 1000 hours, the material balance data are shown in Table 1, the material properties of the biomass pyrolysis liquid and the deoxygenated oil are shown in Table 2, and the composition analysis is shown in Table 3. The GCMS analysis results of the biomass pyrolysis liquid and the deoxygenated oil are shown in FIG. 2 and FIG. 3, respectively, indicating that most of the oxygen in the pyrolysis liquid was converted into water, CO, and CO.sub.2 after hydrodeoxygenation, and thus removed. The resulting deoxygenated oil can be used as a raw material for hydrocracking. The composition of the gas generated in the hydrodeoxygenation reaction is shown in Table 4.

    TABLE-US-00001 Material balance data of the hydrodeoxygenation reaction Raw materials Products Pyrolysis Deoxygenated Aqueous Gas liquid Hydrogen.sup.Note1 oil phase phase.sup.Note2 Weight, g 64160 988 29653 29022 6473 Total, g 65148 65148 Consumption or 98.48 1.52 45.52 44.55 9.93 yield.sup.Note 3, wt % Note 1: Hydrogen represents the amount of hydrogen consumed during thereaction. The flow rate of the gas entering the hydrodeoxygenation reactor and the flow rate of the gas exiting the hydro de oxygenation reactor as well as the hydrogen contents therein were measured and analyzed. The difference between the amount of hydrogen entering the hydrodeoxygenation reactor and the amount of hydrogen exiting the hydrodeoxygenation reactor was used as the hydrogen consumption in the hydrodeoxygenation reaction. Note 2: The gas phase was the gas phase substance produced in the hydrodeoxygenation reaction, excluding the amounts of hydrogen and other gas components in the circulating hydrogen. Note 3: The product yield was the mass percentage of each product over the total consumption (including the hydrogen consumption).

    TABLE-US-00002 TABLE 2 Comparison of properties of the biomass pyrolysis liquid and the deoxygenated oil produced by the hydrodeoxygenation reaction Biomass Deoxygenated pyrolysis liquid oil Density, g/cm.sup.3 1.18 0.91 Viscosity (@20° C.) 80 1.2 cp (@60° C.) 20 0.93 Moisture, % 28 0.0050 HHV (higher 16.7 42.5 heating value), MJ/kg TAN (acid number), 120 11 mgKOH/g Elemental C, wt % 43.6 81.1 composition H, wt % 6.9 11.4 0, wt % 49.4 7.4 Others, wt % <0.1 <0.1 pH value 2.7 / Distillation Initial boiling 50 52 range ° C. point (ASTM  5% 60 105 D1160) 20% 102 137 40% 280 192 60% 375 235 80% 500 297 95% 650 381 98% / 440 Final boiling / 495 point

    TABLE-US-00003 TABLE 3 Comparison of GCMS Note 4 analysis results of the biomass pyrolysis liquid and the dehydrated hydrodeoxygenated oil Biomass pyrolysis Hydro- liquid (dry basis) deoxygenated oil Alcohols 13.06 2.48 Lipids 7.94 4.73 Ketones 12.93 1.15 Aldehydes 15.33 0.00 Ethers 0.66 2.05 Carboxylic acids 16.46 0.01 Phenols 18.75 15.15 Alkanes 4.32 47.65 Aromatic 10.16 25.28 hydrocarbons Unsaturated 0.39 1.50 hydrocarbons Note 4: GCMS analysis was performed under the condition of heating up to 350° C., excluding substances having a boiling point higher than this temperature.

    TABLE-US-00004 TABLE 4 The composition based on volume percentage of the gas generated by the hydrodeoxygenation reaction (excluding hydrogen) Component, V/V% CO 6.95 CO.sub.2 53.81 CH.sub.4 20.53 C.sub.2H.sub.6 9.27 C.sub.2H.sub.4 1.16 C.sub.3 5.96 C.sub.4 1.96 C.sub.5 and C.sub.5+ 0.33

    [0065] In the hydrodeoxygenation reaction, the aldehydes, sugars and some carboxylic acids that are prone to polymerization in the biomass pyrolysis liquid were converted into stable alcohols and hydrocarbons, and some alcohols, carboxylic acids and other polar substances were converted into hydrocarbons, hydrogen, water, CO and CO.sub.2 in the reaction. Some unreacted alcohols and carboxylic acids entered the aqueous phase in the oil-water separation apparatus. The oil phase mainly included phenolic substances, hydrocarbons and other substances having stable properties. The fraction range of the deoxygenated oil was reduced greatly to a maximum boiling point of 495° C. for the reason that the macromolecular components in the biomass pyrolysis liquid were mainly linked by oxygen atoms, but oxygen was released in the form of water, CO and CO.sub.2 during the hydrodeoxygenation process, thereby tailoring the macromolecules in the biomass pyrolysis liquid into small molecules such as hydrocarbons, alcohols, and carboxylic acids.

    [0066] It was further discovered in the experiment that, relative to the mass of the biomass pyrolysis liquid, the total oxygen content was reduced from 49.4% to 7.4%. After deducting the 24.89% oxygen content in the water content of the biomass pyrolysis liquid, the amount of oxygen removed in the hydrodeoxygenation reaction accounted for 17.11%. The amount of oxygen removed in the form CO and CO.sub.2 in the hydrodeoxygenation reaction was 5.10%, mainly because of the decarbonylation reaction and decarboxylation reaction. Some alcohols were also likely to be cracked in the presence of water vapor to generate hydrogen, but the generation of hydrogen was accompanied by the generation of CO and CO.sub.2. So, the overall hydrogen-to-oxygen ratio would not be changed. 12.01% of the oxygen was removed in the form of water in the hydrodeoxygenation reaction. Theoretically, the mass of hydrogen required to be consumed in order to remove the oxygen was about 1.50% of the biomass pyrolysis liquid. The actual amount of hydrogen consumed was 1.54% of the mass of the biomass pyrolysis liquid, indicating that the main process in the hydrodeoxygenation reaction was deoxygenation, and only a small part of the carbon-carbon bonds were broken. In addition, judging from the composition of the gas generated during the reaction, the mass of CO and CO.sub.2 accounted for about 70% of the generated gas, confirming again that the main process in the hydrodeoxygenation reaction was deoxygenation, and only a small amount of light hydrocarbons were produced. Moreover, a part of the light hydrocarbons were derived from deoxygenation of methyl esters and ethyl esters.

    [0067] After the hydrodeoxygenation reaction in this Example ran for 2000 hours, the catalyst was removed from the fluidized bed hydrodeoxygenation reactor and fully washed with a furan solution. The weight of the catalyst after drying was compared with the weight of the catalyst added before the reaction, and there was no increase in weight. This means that little or no coke was formed.

    [0068] The fresh hydrogen 21 was mixed with the regenerated hydrogen 20. After being pressurized by a hydrogen compressor 22, the resulting hydrogen 23 was mixed with the deoxygenated oil 19. After being heated by a heating furnace 24, the gas-liquid mixture 25, as a raw material, entered a single-stage fixed-bed hydrocracking reactor 26. The temperature of the hydrocracking reaction was controlled at 360° C. by adjusting the temperature of the gas-liquid mixture 25. After the reaction effluent 27 passed through a cold high pressure gas-liquid separator 28, the gas substance 29 was supplied as supplementary hydrogen to be used in the hydrodeoxygenation reaction. After the liquid substance 30 was separated by an oil-water separator 31, the aqueous phase substance 32 entered the water treatment facility 15, and the high-quality fuel oil 33 produced was heated by a heating furnace 34 and then entered a fractionation tower 35. The light hydrocarbon fraction 36 was discharged from the top of the fractionation tower; the naphtha fraction 37 was extracted from the upper part of the fractionation tower; and the fraction 38 having a boiling range of 200-240° C. was extracted from the side line of the middle part of the fractionation tower. A portion of the fraction 38 was cooled by a cooler 39, pressurized by a hydrogen donor pump 40, and then recycled back to the hydrodeoxygenation reactor as the hydrogen donor 2. The other portion of the fraction 38 was discharged and combined into the light diesel 41 pipeline at the lower part of the tower. The heavy diesel fraction 42 at the bottom of the tower could be discharged for sale as a product. In order to increase the output of the naphtha fraction, gasoline and diesel, the heavy diesel fraction 41 discharged from the bottom of the tower could also be mixed with the hydrogen donor 2, and then recycled back to the hydrodeoxygenation reactor. It could pass through the two-stage reactor of hydrodeoxygenation and hydrocracking to produce distillate materials having lower boiling points.

    [0069] The hydrogen-to-oil ratio in the hydrocracking reaction was controlled by controlling the flow rate of hydrogen 23 with a hydrogen compressor 22. In this Example, the hydrogen-to-oil ratio in the hydrocracking reaction was 700:1. In this Example, CoW/Al.sub.2O.sub.3 was used as the hydrocracking catalyst. The liquid hourly volume space velocity in this Example was 2.0 h.sup.−1, and the reaction pressure was 15.0 MPa.

    [0070] The pressure in the hydrocracking reaction was higher than that in the hydrodeoxygenation reaction, because higher pressure was desirable to increase the partial pressure of hydrogen in the hydrocracking reaction, thereby promoting the reaction. At the same time, after the hydrocracking reaction, the gaseous substance 29 obtained by gas-liquid separation needed to be recycled to the hydrodeoxygenation reaction, so a higher pressure was conducive to the pressure balance of the system. In addition, it was also found in this experiment that a lower hydrogen concentration could also meet the requirements of the hydrodeoxygenation reaction in the present disclosure. Compared with a method in which the gaseous substance 29 was discharged into a waste hydrogen pipeline to be regenerated with a hydrogen purification facility, and an additional hydrogen compressor was needed to increase its pressure (for pressure balance) before it was incorporated into the pipeline of the circulating hydrogen 9, in the present disclosure, the gaseous substance 29 from the hydrogen cracking reaction was incorporated into the pipeline of the circulating hydrogen 9, and the circulating hydrogen compressor 8 was shared. This method saved investment and energy consumption greatly.

    [0071] The material balance data of the hydrocracking reaction in this Example are shown in Table 5; the material properties of the raw material for the hydrocracking reaction and the resulting high-quality fuel oil are shown in Table 6; and the composition analysis of the gas produced in the hydrocracking reaction is shown in Table 7.

    TABLE-US-00005 TABLE 5 Material balance data of the hydrocracking reaction Raw materials Products De- High- oxygenated Hydro- quality Gas oil, gen.sup.Note 5, fuel oil, Aqueous phase.sup.Note 6, g g g phase, g g Weight 31120 265 26881 2495 2009 Total, g 31385 31385 Con- 99.16 0.84 85.65 7.95 6.4 sumption or yield.sup.Note 7, wt % .sup.Note 5: Hydrogen represents the amount of hydrogen consumed during the hydrocracking reaction. The flow rate of the gas entering the hydrocracking reactor and the flow rate of the gas exiting the hydrocracking reactor as well as the hydrogen contents therein were measured and analyzed. The difference between the amount of hydrogen entering the hydrocracking reactor and the amount of hydrogen exiting the hydrocracking reactor was used as the hydrogen consumption in the hydrocracking reaction. .sup.Note 6: The gas phase was the gas phase substance produced in the hydrocracking reaction, excluding hydrogen. .sup.Note 7: The product yield was the percentage of each product over the total consumption (including the hydrogen consumption).

    TABLE-US-00006 TABLE 6 Comparison of the properties of the deoxygenated oil and the fuel oil produced by the hydrocracking reaction Deoxygenated oil High-quality fuel oil Density, g/cm.sup.3 0.91 0.82 HHV, MJ/kg 42.5 46.2 TAN, mgKOH/g 11 0.2 Elemental C, % 81.1 87.9 composition H, % 11.4 12.0 O, % 7.4 <0.01 Others, % <0.1 <0.1, wherein S < 10 ppm Distillation Initial 52 55 range boiling ° C. point (ASTM  5% 105 89 D1160) 20% 137 135 40% 192 168 60% 235 217 80% 297 277 95% 381 341 98% 440 375 Final 495 420 boiling point

    TABLE-US-00007 TABLE 7 Gas phase analysis results for the hydrocracking Tail gas composition, Tail gas composition V/V % (excluding hydrogen), V/V % H.sub.2 91.37 / CO 0.21 2.46 CO.sub.2 0.20 2.27 CH.sub.4 4.85 56.14 C.sub.2H.sub.6 1.76 20.41 C.sub.2H.sub.4 0.00 0.00 C.sub.3 0.70 8.13 C.sub.4 0.52 6.05 C.sub.5 and C.sub.5+ 0.39 4.54

    [0072] In the hydrocracking reaction, while oxygen was further removed, the macromolecular substances were cracked into small molecules. Oxygen was completely removed. The sulfur content was less than 10 ppm. The final boiling point was reduced from 495° C. to 420° C. The content of heavy diesel was about 2%. It could be sold as a product. FIG. 4 shows the analysis results of the molecular weight distribution (GPC) of the dry biomass pyrolysis liquid, high-quality fuel oil, diesel and gasoline. It's indicated that the mixture obtained by hydrodeoxygenation and hydrocracking of the pyrolysis liquid included naphtha, gasoline, diesel and kerosene fractions, and the mixture was similar to gasoline and diesel. It was also found in this Example that, in order not to produce heavy diesel, the heavy diesel discharged from the bottom of the tower was mixed with the hydrogen donor and recycled back to the fluidized bed hydrodeoxygenation reactor, and underwent two-stage reactions of hydrodeoxygenation and hydrocracking. After a long-term operation, it was found that the amount of the products in this part of boiling range did not increase, indicating that this part of the substances could be hydroprocessed into low boiling point substances by the process and catalyst of the present disclosure.

    EXAMPLE 2

    [0073] In this Example, two-stage hydrodeoxygenation reactors in series and two-stage hydrocracking reactors in series were used. The hydrogen donor was a high-quality fuel oil product having a boiling range of 180-240° C. obtained according to the present disclosure. In the first-stage hydrodeoxygenation reaction, the same catalyst Pd/C as used in Example 1 was used. In the second-stage hydrodeoxygenation reaction, NiMo/Al.sub.2O.sub.3 was used as the catalyst. The temperature of the first-stage hydrodeoxygenation reaction was controlled at 280° C., and the temperature of the second-stage hydrodeoxygenation reaction was controlled at 330° C. Different catalysts were used in the fixed bed reactions. The catalyst used in the first-stage refining cracking reaction was CoMo/Al.sub.2O.sub.3, the reaction temperature was controlled at 180° C., and the liquid hourly volume space velocity was 4.010. The catalyst in the second-stage hydrocracking reaction was NiW/Al.sub.2O.sub.3. The reactor size, catalyst loading, and liquid hourly volume space velocity for the second-stage hydrocracking reaction were the same as in Example 1, and the temperature was controlled at 350° C. The other operating conditions and the process flow were the same as in Example 1.

    TABLE-US-00008 TABLE 8 Comparison of the properties of the deoxygenated oil produced in Example 2 and Example 1 after the hydrodeoxygenation reaction was run for 3000 h Example 1 Example 2 Density, g/ml 0.91 0.91 Moisture, % 0.0050 0.0050 HHV, MJ/kg 42.5 43.2 TAN, mgKOH/g 11 10 Elemental C 81.1 81.6 composition H 11.5 12.2 wt % O 7.4 6.2 Others <0.1 <0.1 Distillation Initial boiling 52 52 range point ° C.  5% 105 103 (ASTM 20% 137 135 D1160) 40% 192 187 60% 235 233 80% 297 295 95% 381 374 98% 440 432 Final boiling 495 485 point

    TABLE-US-00009 TABLE 9 Comparison of the properties of the high-quality fuel oil produced in Example 2 and Example 1 after the hydrodeoxygenation reaction was run for 3000 h Example 1 Example 2 Density, g/ml 0.82 0.82 HHV, MJ/kg 46.2 46.4 TAN, mgKOH/g 0.2 0.2 Elemental C 87.9 87.8 composition H 12.1 12.2 wt % O <0.01 <0.01 Others <0.1, wherein <0.1, wherein S < 10 ppm S < 10 ppm Distillation Initial 55 55 range boiling ° C. point (ASTM  5% 89 86 D1160) 20% 135 132 40% 168 165 60% 217 208 80% 277 275 95% 341 332 98% 375 370 Final 420 415 boiling point

    [0074] By comparing with the single-stage hydrodeoxygenation reaction and the single-stage hydrocracking reaction in Example 1, it was found that the two-stage fluidized bed hydrodeoxygenation plus fixed-bed hydrofining plus hydrocracking cascade reactions could provide substantially the same high-quality fuel oil yield as Example 1, because all reactions were carried out mainly for the purpose of hydrodeoxygenation, wherein components prone to polymerization were converted into stable components while oxygen was removed. At the same time, because the macromolecular substances in the biomass pyrolysis liquid were formed mainly with oxygen atoms as linkages, in the process of deoxygenation, these macromolecular substances became small molecular substances. In addition, the amount of fused ring aromatic hydrocarbons comprising three or more rings was extremely small in the biomass pyrolysis liquid. Thus, the final boiling point of the produced fuel was lower than 420° C., and the proportion of heavy diesel was less than 2%.

    [0075] In the hydrodeoxygenation reactions of this Example, due to the two-stage reactions, the oxygen content in the deoxygenated oil was reduced from 7.4% to 6.2%, suggesting that the deoxygenation effect was improved significantly. Table 8 shows the specific data. It was also found in this Example that the use of the two-stage fixed-bed hydrofining and hydrocracking in series did not bring about significant change to the yield and product properties of the produced high-quality fuel oil (see Table 9 for the specific data), but the catalyst life could be prolonged. See Table 10 for details.

    TABLE-US-00010 TABLE 10 Comparison of the influence of single-stage hydrocracking reaction and two-stage hydrocracking reactions on catalyst life Example 1 Example 2 Continuous running time, h 6000 6000 Increase of the pressure drop 0.42 0.22 of the reactor, MPa Fuel oil yield, % 85.65 85.68

    [0076] In this Example, it was found that the main function of the first-stage fixed-bed hydrogenation reaction was to further hydroprocess, at a lower temperature, the unsaturated hydrocarbons left in the hydrodeoxygenated oil due to incomplete treatment and prone to polymerization, so as to obtain more stable substances. See Table 11 for the specific data. In the second-stage fixed-bed hydrocracking reaction, the polymerization reaction rate was reduced greatly. As a result, when the second-stage hydrocracking reaction in this Example and the hydrocracking reaction in Example 1 were carried out under exactly the same conditions, the pressure drop in the second-stage hydrocracking reactor increased at a lower rate, and thus the service life of the catalyst was extended greatly.

    TABLE-US-00011 TABLE 11 Comparison of the GCMS analysis results of the deoxygenated oil in Example 2 and the oil after the first-stage hydrocracking reaction Oil obtained after the first-stage Deoxygenated oil hydrocracking reaction Alcohols 2.48 2.49 Lipids 4.73 3.98 Ketones 1.15 0.52 Aldehydes 0.00 0.00 Ethers 2.05 1.23 Carboxylic acids 0.01 0.01 Phenols 15.15 15.08 Alkanes 47.65 49.55 Aromatic 25.28 26.95 hydrocarbons Unsaturated 1.50 0.1 hydrocarbons

    Example 3

    [0077] In this Example, a single-stage hydrodeoxygenation reactor was used. The biomass pyrolysis liquid was a liquid product obtained by rapid pyrolysis of wheat stalks. The hydrogen donor was light diesel. The catalyst used in the hydrodeoxygenation reaction was Ru/C (ruthenium supported on a carbon-based material). The other operating conditions were the same as in Example 1. Three-stage fixed-beds in series were used for the hydrocracking reaction. The catalysts used in the first-stage and second-stage hydrocracking reactions were the same as in Example 2, and the other operating conditions were the same as in Example 2. The operating temperature of the third-stage hydrocracking reaction was 380° C. The catalyst and other operating conditions used in the third-stage hydrocracking reaction were the same as in the second-stage hydrocracking reaction.

    [0078] Table 12 shows a comparison of the properties of the high-quality fuel obtained in this Example with those obtained in Examples 1 and 2 after 2000 hours of continuous operation.

    TABLE-US-00012 TABLE 12 Comparison of the properties of the high-quality fuel produced in Example 3 with those in Examples 1 and 2 Example 1 Example 2 Example 3 Density, g/ml 0.82 0.82 0.82 HHV, MJ/kg 46.2 46.4 46.4 TAN, mgKOH/g 0.2 0.2 0.2 Elemental C 87.9 87.8 87.8 composition H 12.1 12.2 12.2 wt % O <0.01 <0.01 <0.01 Others <0.1, <0.1, <0.1, wherein Wherein Wherein S < 10 ppm S < 10 ppm S < 10 ppm Distillation Initial 55 55 55 range boiling ° C. point (ASTM  5% 89 86 86 D1160) 20% 135 132 133 40% 168 165 165 60% 217 208 209 80% 277 275 276 95% 341 332 333 98% 375 370 369 Final 420 415 414 boiling point

    [0079] It was found from the comparison that the high-quality fuel oil yield and fuel oil properties obtained using the single-stage hydrodeoxygenation reactor plus the three-stage fixed-bed hydrocracking reactors in series were substantially the same as those in Examples 1 and 2. This suggests that after the hydrodeoxygenation arrived at a certain level, the hydrocracking reaction had a large influence on the performances of the product. In addition, it was also found that the use of two-stage hydrocracking reactors in series could prolong the life of the hydrocracking catalyst, similar to Example 2.

    Example 4

    [0080] In this Example, three-stage fluidized bed hydrodeoxygenation reactors in series were used. The biomass pyrolysis liquid was a liquid product obtained by slow hydrolysis of a mixture of poplar branches and bark. The hydrogen donor was a substance having a boiling range of 180-240° C. obtained by hydroprocessing coal tar. The catalyst used in the first-stage hydrodeoxygenation reaction was NiMn/C (nickel manganese supported on a carbon-based material). The catalyst used in the second-stage hydrodeoxygenation reaction was CoMo/Al.sub.2O.sub.3, the same as that used in the second-stage hydrodeoxygenation reaction in Example 2. The other operating conditions were the same as those in Example 2. The operating temperature of the third-stage hydrodeoxygenation reaction was 370° C., and the catalyst and other operating conditions used in the third-stage hydrodeoxygenation reaction were the same as those in the second-stage hydrocracking reaction. A single-stage fixed bed was used in the hydrocracking reaction, with the use of the same catalyst as in Example 1, namely NiW/Al.sub.2O.sub.3, while the other operating conditions were the same as those in the hydrocracking reaction in Example 1.

    [0081] Table 13 shows a comparison of the properties of the deoxygenated oill obtained in this Example with those obtained in Example 1 after 2000 hours of continuous operation.

    TABLE-US-00013 TABLE 13 Comparison of the properties of the deoxygenated oil produced in Example 4 and Example 1 after the hydrodeoxygenation reaction was run for 2000 h Example 1 Example 4 Dense, g/ml 0.91 0.91 Moisture, % 0.0050 0.0050 HHV, MJ/kg 42.5 43.0 TAN, mgKOH/g 11 9 Elemental C 81.1 81.2 composition H 11.5 11.5 wt % O 7.4 7.3 Others <0.1 <0.1 Distillation Initial boiling 52 52 range point ° C.  5% 105 105 (ASTM 20% 137 136 D1160) 40% 192 190 60% 235 234 80% 297 295 95% 381 378 98% 440 436 Final boiling 495 488 point

    [0082] It was found from the analysis of the experimental results that, with the use of the staged treatment, the deoxygenation effect achieved with a non-noble metal catalyst was the same as that achieved with a noble metal catalyst, and the properties of the deoxygenated oil obtained were similar.

    [0083] Table 14 shows a comparison of the high-quality fuel oil obtained by subjecting the deoxygenated oil obtained from the hydrodeoxygenation reaction to the hydrocracking reaction with the high-quality fuel oils obtained in Examples 1 and 2.

    TABLE-US-00014 TABLE 14 Comparison of the properties of the high-quality fuel oil produced in Example 4 with those in Examples 1 and 2 Example 1 Example 2 Example 4 Density, g/ml 0.82 0.82 0.82 HHV, MJ/kg 46.2 46.4 46.3 TAN, mgKOH/g 0.2 0.2 0.2 Elemental C 87.9 87.8 87.9 composition H 12.1 12.2 12.1 wt % O <0.01 <0.01 <0.01 Others <0.1, <0.1, <0.1, wherein wherein wherein S < 10 ppm S < 10 ppm S < 10 ppm Distillation Initial 55 55 55 range boiling ° C. point (ASTM  5% 89 86 87 D1160) 20% 135 132 134 40% 168 165 167 60% 217 208 212 80% 277 275 276 95% 341 332 335 98% 375 370 372 Final 420 415 417 boiling point

    [0084] It was found from the comparison that the high-quality fuel oil yield and fuel oil properties obtained in this Example were substantially similar to those in Examples 1 and 2. This suggests that after the deoxygenation effect of the hydrodeoxygenation reaction arrived at a certain level, the performances of the hydrocracked products were substantially the same.

    [0085] This Example shows that when a non-precious metal catalyst and multi-stage fluidized bed reactors in series were used for hydrodeoxygenation, an ideal high-quality mixed fuel oil could also be obtained after the resulting deoxygenated oil was hydrocracked.

    Example 5

    [0086] In this Example, a single-stage fluidized bed hydrodeoxygenation reactor was used. The biomass pyrolysis liquid was a liquid product obtained in the carbonization of corn stalks. The catalyst used was CoMo/C. The reaction temperature was 350° C. The mass ratios of the biomass pyrolysis liquid to the hydrogen donor were 1:2, 2:1, and 4:1 respectively, and other operating conditions were the same as in Example 1. Table 15 shows the properties of the deoxygenated oil obtained after 2000 hours of continuous operation.

    TABLE-US-00015 TABLE 15 Comparison of the properties of the deoxygenated oil produced by the hydrodeoxygenation reaction at different ratios of the biomass pyrolysis liquid to the hydrogen donor Ratio of biomass pyrolysis liquid to hydrogen donor 1:2 2:1 4:1 Density, g/ml 0.87 0.91 0.94 Viscosity (@20° C.) 0.95 1.2 4.3 cp (@60° C.) 0.84 0.93 1.45 HHV, MJ/kg 43.57 42.5 40.9 TAN, mgKOH/g 8.5 11 22 Elemental C, % 82.85 81.1 77.79 composition H, % 13.73 11.5 11.36 O, % 3.42 7.4 10.85 Others, % <0.1 <0.1 <0.1 Distillation Initial boiling 51 52 58 range point ° C.  5% 102 105 111 (ASTM 20% 129 137 149 D1160) 40% 185 192 201 60% 226 235 245 80% 285 297 301 95% 370 381 385 98% 428 440 455 Final boiling 482 495 511 point

    [0087] As it can be seen from the results, as the concentration of the biomass pyrolysis liquid in the hydrodeoxygenation reactor increased, the hydrodeoxygenation effect decreased, accompanied by an increased oxygen content in the resulting deoxygenated oil, a decreased heating value, an increased total acid value and an increased amount of the heavy components. Therefore, in addition to increasing the solubility of hydrogen, another purpose of adding the hydrogen donor in the present disclosure is to further reduce the concentration of the biomass pyrolysis liquid in the fluidized bed hydrodeoxygenation reactor, promote deoxygenation, slow down the polymerization reaction rate, and thus increase the catalyst life.

    Example 6

    [0088] In this Example, a single-stage fluidized bed hydrodeoxygenation reactor was used. The catalyst used was NiCr/C. The temperatures of the hydrodeoxygenation reaction were 280° C., 310° C., 340° C. and 370° C. respectively. The other operating conditions were the same as those in Example 1. Table 16 shows the properties of the deoxygenated oil obtained after 1000 hours of continuous operation.

    TABLE-US-00016 TABLE 16 Comparison of the properties of deoxygenated oil produced at different hydrodeoxygenation reaction temperatures Reaction temperature, ° C. 280 310 340 370 Density, g/ml 0.96 0.93 0.91 0.93 Viscosity, cp (@20° C.) 15.4 4.3 1.2 16.5 HHV, MJ/kg 41.0 41.3 42.5 42.1 TAN, mgKOH/g 34 25 11 33 Elemental C, % 78.2 79.1 81.1 81.1 composition H, % 11.6 11.5 11.4 11.4 O, % 10.2 9.4 7.4 7.5 Others, % <0.1 <0.1 <0.1 <0.1

    [0089] As it can be seen from the comparison of the results, as the reaction temperature increased, the hydrodeoxygenation effect was improved, accompanied by a decreased oxygen content in the resulting deoxygenated oil, and an increased heating value. However, when the reaction temperature exceeded 340° C., the oxygen content in the deoxygenated oil did not decrease significantly, the heating value decreased, while the total acid value and the viscosity increased instead. The reason is that, when the temperature is too high, the hydrodeoxygenation reaction is limited by the mass transfer rate and cannot be further accelerated, but the high temperature accelerates the polymerization reaction, such that a portion of the unreacted substances undergo polymerization.

    Example 7

    [0090] In this Example, a single-stage fluidized bed hydrodeoxygenation reactor was used. The catalyst used was CoNb/Al.sub.2O.sub.3. The temperature of the hydrodeoxygenation reaction was 330° C. The reaction pressures were 11.0 MPa, 13.0 Pa, 15.0 MPa and 18.0 MPa, respectively. The other operating conditions were the same as those in Example 1. Table 17 shows the properties of the deoxygenated oil obtained after 1000 hours of continuous operation.

    TABLE-US-00017 TABLE 17 Comparison of the properties of the deoxygenated oil produced at different hydrodeoxygenation reaction pressures Reaction pressure, MPa 11.0 13.0 15.0 18.0 Density, g/ml 0.96 0.93 0.91 0.90 Viscosity, cp (@20° C.) 16.4 6.3 1.2 1.1 HHV, MJ/kg 40.3 41.4 42.5 42.9 TAN, mgKOH/g 43 24 11 9.3 Elemental C, % 78.4 79.6 81.1 81.2 composition H, % 10.6 10.8 11.4 11.5 O, % 10.9 9.5 7.4 7.2 Others, % <0.1 <0.1 <0.1 <0.1

    [0091] As it can be seen from the comparison of the results, as the reaction pressure increased, the hydrodeoxygenation effect was improved, accompanied by a decreased oxygen content in the resulting deoxygenated oil, an increased heating value, a decreased total acid value, and a decreased viscosity. The reason is that, as the pressure increases, the partial pressure of hydrogen in the reaction system increases, which is conducive to the deoxygenation reaction, but the increased pressure will increase the investment and operating costs of the equipment.

    Example 8

    [0092] In this Example, a single-stage fluidized bed hydrodeoxygenation reactor was used. The catalyst used was NiCeZr/Al.sub.2O.sub.3. The reaction temperature was 330° C. The mass ratios of the circulating oil to the biomass pyrolysis liquid (abbreviated as circulation ratio) in the hydrodeoxygenation reaction were 2:1, 3:1, 4:1, 5:1, and 6:1 respectively. The other operating conditions were the same as in Example 1. Table 18 shows the properties of the deoxygenated oil obtained after 1000 hours of continuous operation.

    TABLE-US-00018 TABLE 18 Comparison of the properties of the deoxygenated oil produced by the hydrodeoxygenation reaction at different circulation ratios Circulation ratio 2:1 3:1 4:1 5:1 6:1 Density, g/ml 0.931 0.921 0.913 0.911 0.906 Viscosity, cp (@20° C.) 9.7 4.3 1.2 1.0 1.0 HHV, MJ/kg 41.2 41.8 42.5 42.9 43.1 TAN, mgKOH/g 24 19 11 10 9.5 Elemental C, % 78.4 80.6 81.1 81.2 81.3 composition H, % 10.6 11.2 11.4 11.4 11.4 O, % 10.9 8.2 7.4 7.3 7.2 Others, % <0.1 <0.1 <0.1 <0.1 <0.1

    [0093] As it can be seen from the experimental results, the variation of the circulation ratio of the hydrodeoxygenation reaction has a significant influence on the deoxygenation effect. The main purposes of using the circulating oil include: 1. diluting the biomass pyrolysis liquid to slow down the polymerization rate; 2. driving the catalyst in the reactor to a fluidized state, and co-working with the biomass pyrolysis liquid, the circulating oil, the hydrogen donor, hydrogen, the catalyst and the internal component to form a completely mixed flow catalyst circulation system. If the circulation ratio is too low, the fluidization effect on the catalyst is unsatisfactory, and the circulation ratio may even exceed the operating range of the fluidized bed reactor. In addition, the dilution effect on the raw materials is also greatly degraded, which will lead to insignificant deoxygenation at the end. If the circulation ratio is increased to the operating range of the fluidized bed reactor, an ideal deoxidation effect can be achieved. Further increase in the circulation ratio has little effect on the properties of the resulting deoxygenated oil. If the circulation ratio is too high and exceeds the operating range of the fluidized bed reactor, damage to downstream process equipment will occur. Therefore, it is very important to select an appropriate circulation ratio according to the internal component in the reactor and the characteristics of the catalyst. The preferred circulation ratio in the present disclosure is in the range of 2:1 to 7:1.

    Example 9

    [0094] In this Example, a single-stage fluidized bed hydrodeoxygenation reactor was used. The catalyst was NiRu/C. The reaction temperature was 330° C. The standard state volume ratios of hydrogen to the biomass pyrolysis liquid in the hydrodeoxygenation reaction were 300:1, 500:1, 700:1, 900:1, and 1100:1 respectively. The other operating conditions were the same as in Example 1. Table 19 shows the properties of the deoxygenated oil obtained after 1000 hours of continuous operation.

    TABLE-US-00019 TABLE 19 Comparison of the properties of the deoxygenated oil produced at different hydrogen-to-oil ratios in the hydrodeoxygenation reaction Hydrogen-to-oil ratio, 300:1 500:1 700:1 900:1 1100:1 v/v Density, g/ml 0.931 0.917 0.911 0.910 0.909 Viscosity, cp (@20° C.) 12.3 1.8 1.2 1.0 1.0 HHV, MJ/kg 40.5 41.6 42.5 42.8 42.8 TAN, mgKOH/g 32 18 11 10 9.5 Elemental C, % 78.1 80.6 81.1 81.3 81.3 composition H, % 10.6 11.1 11.4 11.4 11.4 O, % 11.3 8.3 7.4 7.2 7.2 Others, % <0.1 <0.1 <0.1 <0.1 <0.1

    [0095] As it can be seen from the comparison of the deoxygenated oil properties, as the hydrogen-to-oil ratio increased, the hydrodeoxygenation effect was improved, accompanied by a decreased oxygen content in the resulting deoxygenated oil, an increased heating value, a decreased total acid value, and a decreased viscosity. Nonetheless, when the hydrogen-to-oil ratio reached a certain value, the decrease of the oxygen content in the deoxygenated oil, the increase of the heating value, the decrease of the total acid value, and the decrease of the viscosity were not conspicuous. The reason is that, when the hydrogen-to-oil ratio is relatively small, the partial pressure of hydrogen in the reactor is small, and thus the hydrodeoxygenation reaction is incomplete. When the partial pressure of hydrogen reaches a certain level, as the deoxygenation reaction is limited by the mass transfer rate, temperature and other factors, further increase of the hydrogen-to-oil ratio has little effect on the deoxygenation reaction, while a high hydrogen-to-oil ratio will increase the operating cost.

    Example 10

    [0096] In this Example, a single-stage fluidized bed hydrodeoxygenation reactor was used. The catalyst was Ni/C. The reaction temperature was 330° C. The liquid hourly volume space velocities of the hydrodeoxygenation reaction were 0.4 h.sup.−1, 0.6 h.sup.−1, 0.8 h.sup.−1, 1.0 h.sup.−1 and 1.4 h.sup.−1. The other operating conditions were the same as in Example 1. Table 20 shows the properties of the deoxygenated oil obtained after 1000 hours of continuous operation.

    TABLE-US-00020 TABLE 20 Comparison of the properties of the deoxygenated oil produced at different liquid hourly volume space velocities in the hydrodeoxygenation reaction Liquid hourly volume 0.4 0.6 0.8 1.0 1.4 space velocity, h.sup.−1 Density, g/ml 0.902 0.911 0.928 0.942 0.948 Viscosity, cp (@20° C.) 1.1 1.2 4.6 7.8 9.8 HHV, MJ/kg 42.9 42.5 41.7 41.4 41.1 TAN, mgKOH/g 8 11 21 30 35 Elemental C, % 81.3 81.1 80.5 79.2 78.3 composition H, % 11.6 11.4 11.2 10.8 10.5 O, % 7.0 7.4 8.3 10.0 11.2 Others, % <0.1 <0.1 <0.1 <0.1 <0.1

    [0097] As it can be seen from the comparison of the deoxygenated oil properties, in respect of the hydrodeoxygenation effect, as the liquid hourly volume space velocity increased, the oxygen content in the resulting deoxygenated oil increased, the heating value decreased, and the total acid value and viscosity increased. The reason is that, when the liquid hourly volume space velocity increases, some substances that have no time to react will undergo polymerization at high temperatures.

    Example 11

    [0098] In this Example, a single-stage fluidized bed hydrodeoxygenation reactor was used. The catalyst was NiCr/C. The reaction temperature was 330° C. The other operating conditions were the same as in Example 1. After 3000 hours of continuous operation, the activity of the catalyst was found to decrease. After the catalyst was subjected to swirl washing with butanol and reduced, the regenerated catalyst and the primary fresh catalyst were put into the fluidized bed hydrodeoxygenation reactor in a certain ratio. Table 21 compares the properties of the deoxygenated oil produced after 1000 hours of operation with those of the deoxygenated oil produced with no addition of the regenerated catalyst.

    TABLE-US-00021 TABLE 21 Comparison of the properties of the deoxygenated oil produced in the hydrodeoxygenation reaction before and after adding the regenerated catalyst Continuous operating time, h 1000 1000 Weight ratio of regenerated 0 1:4 1:2 1:1 2:1 4:1 catalyst to fresh catalyst Density, g/ml 0.906 0.907 0.907 0.907 0.907 0.907 Viscosity, cp (@20° C.) 1.1 1.1 1.2 1.3 1.4 1.5 HHV, MJ/kg 42.7 42.8 42.7 42.7 42.7 42.6 TAN, mgKOH/g 10 9 10 10 10 11 Elemental C, % 81.2 81.2 81.2 81.2 81.2 81.1 composition H, % 11.5 11.6 11.5 11.5 11.5 11.5 O, % 7.2 7.1 7.2 7.2 7.2 7.3 Others, % <0.1 <0.1 <0.1 <0.1 <0.1 <0.1

    [0099] As a comparison between the experimental results after regeneration of the catalyst with reduced activity and the experimental results without adding the regenerated catalyst, when the experiment without adding the regenerated catalyst ran for 1000 hours, the hydrodeoxygenation reaction reduced the mass content of oxygen in the biomass pyrolysis liquid from 49.4% to 7.2%; when the experiment with the addition of 80% regenerated catalyst ran for 1000 hours, the hydrodeoxygenation reaction reduced the mass content of oxygen in the biomass pyrolysis liquid from 49.4% to 7.3%. The comparison shows that the deoxygenation rate hardly changes, indicating that the catalyst regeneration method of the present disclosure can restore the catalyst activity by more than 99%.

    Example 10

    [0100] In this Example, a single-stage fixed-bed hydrocracking reactor was used. The catalyst was CoMo/Al.sub.2O.sub.3. The temperatures of the hydrocracking reaction were 300° C., 330° C., 360° C. and 390° C., respectively. The other operating conditions were the same as those for the hydrocracking reaction in Example 1. The deoxygenated oil obtained in Example 1 was used as the raw material. Table 22 shows the properties of the fuel oil produced after 1000 hours of continuous operation.

    TABLE-US-00022 TABLE 22 Comparison of the properties of the fuel oil produced at different hydrocracking reaction temperatures Reaction temperature, ° C. 300 330 360 390 Density, g/ml 0.829 0.826 0.821 0.816 HHV, MJ/kg 45.9 46.0 46.2 46.2 TAN, mg KOH/g 0.2 0.2 0.2 0.1 Distillation Initial boiling 56 55 53 51 range point ° C.  5% 92 89 88 83 (ASTM 20% 137 135 134 130 D1160) 40% 172 168 165 161 60% 222 217 215 211 80% 283 277 274 269 95% 345 341 340 337 98% 381 375 373 370 Final boiling 426 420 418 415 point

    [0101] As it can be seen from the experimental results, as the temperature increased, the density of the fuel oil obtained decreased, the heating value increased, and the final boiling point decreased. The reason is that, as the temperature increases, the hydrocracking reaction rate increases. However, if the temperature is too high, the proportion of light hydrocarbon components obtained increases, and the yield of the fuel oil decreases.

    Example 13

    [0102] In this Example, a single-stage fixed-bed hydrocracking reactor was used. The catalyst was NiW/Al.sub.2O.sub.3. The pressures of the hydrocracking reaction were 12.0 MPa, 13.5 MPa, 15.0 MPa and 18.0 MPa, respectively. The other operating conditions were the same as those for the hydrocracking reaction in Example 1. The deoxygenated oil obtained in Example 1 was used as the raw material. Table 23 shows the properties of the fuel oil produced after 1000 hours of continuous operation.

    TABLE-US-00023 TABLE 23 Comparison of the properties of the fuel oil produced at different hydrocracking reaction pressures Reaction pressure, MPa 12.0 13.5 15.0 18.0 Density, g/ml 0.825 0.823 0.821 0.820 HHV, MJ/kg 46.0 46.1 46.2 46.2 TAN, mgKOH/g 0.2 0.2 0.2 0.1 Distillation Initial boiling 56 55 55 54 range point ° C.  5% 92 90 89 88 (ASTM 20% 137 136 135 134 D1160) 40% 170 169 168 166 60% 220 218 217 216 80% 282 278 277 275 95% 345 342 341 338 98% 380 376 375 373 Final boiling 426 421 420 418 point

    [0103] As it can be seen from the experimental results, as the reaction pressure increased, the density of the fuel oil obtained decreased, the heating value increased, and the final boiling point decreased. The reason is that, as the pressure increases, the hydrocracking reaction rate increases. However, if the pressure is too high, the proportion of light hydrocarbon components obtained increases, and the yield of the fuel oil decreases.

    Example 14

    [0104] In this Example, a two-stage fixed-bed hydrocracking reactor was used. The catalyst used was the same as that used in the hydrocracking reaction in Example 2. The standard state volume ratios of hydrogen to deoxygenated oil in the hydrocracking reaction were 300:1, 500:1, 700:1, 900:1 and 1100:1, respectively. The other operating conditions were the same as those for the hydrocracking reaction in Example 2. The deoxygenated oil obtained in Example 2 was used as the raw material. Table 24 shows the properties of the fuel oil produced after 1000 hours of continuous operation.

    TABLE-US-00024 TABLE 24 Comparison of the properties of the fuel oil produced by the hydrocracking reaction at different hydrogen-to-oil volume ratios Hydrogen-to-oil ratio 300:1 500:1 700:1 900:1 1100:1 Density, g/ml 0.829 0.826 0.821 0.816 0.815 HHV, MJ/kg 45.9 46.0 46.2 46.2 46.5 TAN, mgKOH/g 0.2 0.2 0.2 0.1 0.1 Distillation Initial boiling 56 55 53 52 50 range ° C. point  5% 95 90 88 87 85 20% 142 137 134 133 132 40% 176 170 165 163 161 60% 228 221 215 213 211 80% 289 277 274 271 269 95% 353 344 340 337 335 98% 390 379 373 370 367 Final boiling 435 423 418 417 415 point

    [0105] As it can be seen from the experimental results, as the hydrogen-to-oil ratio increased, the density of the fuel oil obtained from the reaction decreased, the heating value increased, and the final boiling point decreased. The reason is that, as the hydrogen-to-oil ratio increases, the partial pressure of hydrogen increases, and thus the hydrocracking reaction rate increases. As a result, the proportion of light hydrocarbon components obtained increases, and the yield of the fuel oil decreases slightly.

    Example 15

    [0106] In this Example, a single-stage fixed-bed hydrocracking reactor was used. The catalyst used was the same as that used in the hydrocracking reaction in Example 1. The liquid hourly volume space velocities in the hydrocracking reaction were 1.0 h.sup.−1, 1.5 h.sup.−1, 2.0 h.sup.−1, 3.0 h.sup.−1 and 4.0 h.sup.−1, respectively. The other operating conditions were the same as those in Example 1. The deoxygenated oil obtained in Example 1 was used as the raw material. Table 25 shows the properties of the fuel oil produced after 1000 hours of continuous operation.

    TABLE-US-00025 TABLE 25 Comparison of the properties of the fuel oil produced at different liquid hourly volume space velocities in the hydrocracking reaction Liquid hourly 1.0 1.5 2.0 3.0 4.0 volume space velocity, h.sup.−1 Density, g/ml 0.817 0.820 0.821 0.831 0.842 HHV, MJ/kg 46.5 46.3 46.2 45.8 45.4 TAN, mgKOH/g 0.1 0.2 0.2 0.3 0.4 Distillation Initial 54 55 55 55 56 range ° C. boiling point  5% 86 87 89 92 95 20% 132 134 135 138 142 40% 164 166 168 171 175 60% 212 215 217 220 225 80% 271 274 277 281 286 95% 337 339 341 345 350 98% 369 372 375 378 384 Final 413 417 420 424 432 boiling point

    [0107] As it can be seen from the experimental results, as the liquid hourly volume space velocity increased in the reaction, the density of the fuel oil obtained from the reaction increased, the heating value decreased, and the final boiling point increased.

    Example 16

    [0108] In this Example, a single-stage fixed-bed hydrocracking reactor was used. The catalyst used was the same as that used in the hydrocracking reaction in Example 1. The mass contents of free water in the raw materials of the hydrocracking reaction were 10 ppm, 100 ppm, 0.1%, 0.5%, and 1%, respectively. The other operating conditions were the same as those in Example 1. Table 26 shows the properties of the high-quality fuel oil produced after 1000 hours of continuous operation.

    TABLE-US-00026 TABLE 26 Comparison of the properties of the high-quality fuel oil produced by the hydrocracking reaction at different free water contents Mass content of 10 ppm 100 ppm 0.1% 0.5% 1.0% free water Density, g/ml 0.815 0.827 0.835 0.842 0.851 HHV, MJ/kg 46.5 46.1 45.8 45.4 44.8 TAN, mgKOH/g 0.1 0.2 0.5 2.1 3.5 Distillation Initial 55 55 55 55 55 range ° C. boiling point  5% 87 88 89 89 92 20% 131 135 136 138 140 40% 163 167 168 170 172 60% 211 213 215 220 223 80% 270 274 278 281 285 95% 336 338 346 348 352 98% 368 374 378 382 388 Final 410 419 421 428 438 boiling point

    [0109] As it can be seen from the comparison of the properties of the deoxygenated oil, in respect of the hydrodeoxygenation effect, as the mass content of free water increased, the total acid value of the product obtained increased, and the heating value decreased. The reason is that, when the hydrocracking catalyst is rich in free water, its support skeleton is prone to collapse. In addition, when a sulfide catalyst is used, free water will also accelerate deactivation of the catalyst. Therefore, an increased free water content in the raw materials for the hydrocracking reaction will accelerate deactivation of the catalyst and affect long-term operation of the reaction. However, a decreased mass content of free water imposes a higher requirement on the dehydration efficiency of the deoxygenated oil, which will increase the investment cost and operating cost. In view of the characteristics of the catalyst in the present disclosure, the free water content in the raw materials for the hydrocracking reaction in the present disclosure is preferably 10-1000 ppm.

    Example 17

    [0110] FIG. 5 shows a schematic view of the process flow of this Example.

    [0111] In this Example, two-stage fixed-bed hydrocracking reactors in series were used, and the catalyst used was the same as that used in the hydrocracking reaction in Example 2. After the deoxygenated oil 19 and heavy diesel, wax oil or coal tar 43 were heated in the heating furnace 24, they entered the first-stage fixed-bed hydrofining reactor 44 for reaction, and the reaction product 45 was heated in the heating furnace 46 and then entered the fixed-bed hydrocracking reactor 26 for co-refining. The other operating conditions were the same as those for the hydrocracking reaction in Example 2. Table 27 shows the properties of the high-quality fuel oil produced after 3000 hours of continuous operation.

    TABLE-US-00027 TABLE 27 Comparison of the properties of the high-quality fuel oil obtained by co-refining the deoxygenated oil with heavy diesel, wax oil or coal tar Type of purchased oil Heavy Heavy Heavy Wax Low- diesel diesel diesel oil temperature coal tar Weight percentage of 0 30 60 30 30 purchased oil over the total amounts of deoxygenated oil and purchased oil, wt % Density, g/ml 0.816 0.817 0.822 0.818 0.819 HHV, MJ/kg 46.4 46.3 46.2 46.3 46.2 TAN, mgKOH/g 0.1 0.2 0.3 0.2 0.3 Sulfur content, ppm 5 6 8 6 8 Distillation Initial 55 55 55 55 55 range ° C. boiling point  5% 86 87 90 87 89 20% 132 134 136 135 136 40% 165 168 172 169 171 60% 208 214 222 215 223 80% 275 278 282 278 280 95% 332 342 347 340 347 98% 370 374 380 374 380 Final 415 454 463 457 461 boiling point Note: The low-temperature coal tar in this Example was a liquid substance obtained by low-temperature cracking of candle bituminous coal (<500° C.).

    [0112] As it can be seen from the results, the high-quality fuel oil obtained by co-refining deoxygenated oil with heavy diesel, wax oil or coal tar can also meet the relevant standards of vehicle fuel. Since the deoxygenated oil produced according to the present disclosure can be completely miscible with heavy diesel, wax oil or coal tar in any ratio, the requirements of the raw materials for the hydrocracking reaction in the present disclosure can be met. In addition, the fixed bed catalyst used is similar to the traditional catalyst used for hydroprocessing heavy diesel, wax oil or coal tar. The implementation results show that the present disclosure can achieve co-refining of deoxygenated oil with heavy diesel, wax oil or coal tar, and can make use of traditional refining equipment to achieve co-refining, thereby saving equipment investment, and greatly increasing the capacity of the equipment for producing final products, so that the economy of the present disclosure is further increased.