Biofuel oil preparation device and biofuel oil preparation method

Abstract

The invention provides a biofuel preparation device and method, the biofuel preparation device comprises a multifunctional hydrogenation reactor, a suspended bed reaction zone, a fluidized bed reaction zone and a gas-liquid separation zone are integrally arranged in a shell of the multifunctional hydrogenation reactor from bottom to top, and the suspended bed reaction zone is provided with a homogeneous slurry inlet and a lower liquid product outlet; a first reaction zone and a second reaction zone are arranged in the fluidized bed reaction zone; the first reaction zone and the second reaction zone are respectively provided with a microsphere catalyst feeding port, a microsphere catalyst discharging port and a hydrogen inlet; the gas-liquid separation area is provided with a gas outlet and an upper liquid product outlet; the gas outlet is connected with a hydrogen circulating system; and the microspherical catalyst outlet and the microspherical catalyst inlet are used for connecting a catalyst regeneration system. According to the biofuel preparation device provided by the invention, the whole hydro-conversion process from raw material pretreatment to deep refining to product separation is highly integrated and completed in one reactor.

Description

Technical Field

[0001] This invention belongs to the field of efficient biomass energy conversion technology, and more specifically, relates to a biofuel preparation device. Background Technology

[0002] Biomass energy, as a renewable and clean energy source, is one of the important ways to replace traditional fossil fuels and achieve energy structure transformation. The production of biofuels such as biodiesel and bio-aviation kerosene from animal and vegetable oils, waste oils, and non-grain biomass raw materials has become a current research hotspot and industrialization direction.

[0003] Currently, one of the mainstream technologies for biofuel production is hydrotreating. Traditional hydrotreating processes, such as fixed-bed hydrotreating, require extremely high purity and homogeneity of the feedstock. However, biomass feedstocks available for large-scale utilization are widely available and complex in composition, often including low-quality feedstocks with high impurities, high metal content, and high oxygen content, such as waste cooking oil, animal fats, and plant asphalt. These impurities can easily lead to rapid deactivation of fixed-bed catalysts, increased bed pressure drop, and even reactor blockage, severely affecting the stability and economic efficiency of the plant. To treat such feedstocks, slurry-bed hydrotreating technology has been proposed. It uses powdered catalysts, which are better resistant to impurities, but the products often fail to meet high-quality fuel standards directly and usually require subsequent refining reactors (such as fixed-bed or fluidized-bed reactors) for further processing.

[0004] This series-connected process has drawbacks such as long process flow, large equipment investment, low energy utilization efficiency, and poor operational flexibility. In particular, the existing process lacks adaptability and economic efficiency when product plans need to be flexibly adjusted according to raw material characteristics or market demand. Summary of the Invention

[0005] This invention provides a biofuel preparation apparatus that integrates the entire hydrogenation conversion process, from raw material pretreatment to deep refining and product separation, into a single reactor.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A biofuel preparation device is provided, comprising a multifunctional hydrogenation reactor. The reactor's shell integrates, from bottom to top, a slurry bed reaction zone, a fluidized bed reaction zone, and a gas-liquid separation zone. The slurry bed reaction zone has a homogeneous slurry inlet and a lower liquid product outlet. The fluidized bed reaction zone is internally divided into two series-connected catalyst beds—a first reaction zone and a second reaction zone—by three layers of filters. The first and second reaction zones each have independent microsphere catalyst inlet, microsphere catalyst outlet, and hydrogen inlet. The gas-liquid separation zone has a gas outlet and an upper liquid product outlet. The gas outlet is used to connect to a hydrogen circulation system; the microsphere catalyst outlet is used to connect to a catalyst regeneration system; and the microsphere catalyst inlet is used to connect to the catalyst regeneration system.

[0007] In one possible implementation, a diversion tank is provided inside the suspended bed reaction zone, which divides it into an inner reaction zone and an outer reaction zone. The homogeneous slurry inlet is connected to the bottom of the inner reaction zone, and the lower liquid product outlet is located at the bottom of the outer reaction zone.

[0008] In one possible implementation, the shell of the multifunctional hydrogenation reactor is equipped with a jacket, and the shell sections corresponding to the first and second reaction zones of the suspended bed reaction zone and the boiling bed reaction zone are respectively equipped with independent jacket sections, and each jacket section is equipped with an independent heat transfer oil inlet and heat transfer oil outlet.

[0009] In one possible implementation, a gas distributor is provided below both the first and second reaction zones of the fluidized bed reaction zone, and the gas distributor is connected to the hydrogen inlet of the corresponding reaction zone.

[0010] The present invention also provides a method for preparing biofuel, utilizing a biofuel preparation apparatus and carried out in an environment including a catalyst regeneration system and a hydrogen circulation system, comprising the following steps: S1. Raw material pretreatment: Two or more raw materials are mixed and then filtered, dehydrated, and degassed to obtain mixed raw material oil. S2, Suspended Bed Hydrogenation: The mixed feedstock oil is mixed with the first catalyst and hydrogen to form a homogeneous slurry, which is then preheated and sent to the suspended bed reaction zone for reaction; S3, fluidized bed hydrogenation: The reaction product of step S2 is fed upward into the first reaction zone of the fluidized bed reaction zone, where it reacts under the action of the second catalyst and hydrogen; the reaction liquid continues to enter the second reaction zone, where it continues to react under the action of the third catalyst and hydrogen, to obtain the final reaction liquid; S4. Gas-liquid separation and product separation: The final reaction liquid is separated in the gas-liquid separation zone. The separated hydrogen-rich gas is processed by the hydrogen circulation system and then recycled. The separated liquid product is fractionated to obtain biofuel. S5. Catalyst regeneration and recycling: The first catalyst turbid liquid obtained in step S4 is regenerated by the catalyst regeneration system and then recycled; the second and third catalyst turbid liquids are periodically discharged from the microsphere catalyst outlet, and after being regenerated by the catalyst regeneration system, they are added to the first and second reaction zones respectively through the microsphere catalyst inlet.

[0011] In one possible implementation, the raw materials in step S1 are two or more of cashew nut shell oil, jatropha oil, waste cooking oil, animal fat, plant asphalt, and microalgae oil.

[0012] In one possible implementation, the first catalyst in step S2 is a micron-sized powder catalyst; and in step S3, the second and third catalysts are both microspherical particle catalysts.

[0013] In one possible implementation, the homogenized slurry in step S2 is preheated to 150-200℃; the reaction conditions for hydrogenation in the suspended bed are: temperature 350-420℃, pressure 15-20MPa, and liquid hourly space velocity 0.5-1.0h. - ¹, Hydrogen-to-oil volume ratio 800-1500:1.

[0014] In one possible implementation, the reaction conditions for hydrogenation in the fluidized bed in step S3 are: temperature 350-400℃ and pressure 15-20MPa.

[0015] In one possible implementation, in step S4, aviation kerosene products with a distillation temperature range of 150-250°C and / or biodiesel products with a distillation temperature range of 180-360°C are obtained by fractionation.

[0016] The biofuel production apparatus provided in this embodiment, compared with existing technologies, achieves a highly integrated hydrogenation conversion process, from raw material pretreatment to deep refining and product separation, all within a single reactor. This design completely replaces the complex layout of multiple devices connected in series, such as suspended beds, fixed beds / fluidized beds, and separators, in traditional processes. This significantly shortens the process flow, simplifies equipment connection pipelines, and thus significantly reduces the total equipment investment, floor space, and energy loss caused by material transfer and repeated heating and cooling. At the same time, it improves the compactness, safety, and ease of operation of the entire production system. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a front view schematic diagram of the biofuel preparation apparatus provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the process flow for the biofuel preparation method provided in an embodiment of the present invention.

[0019] The following are the labeling elements in the figure: 10. Multifunctional hydrogenation reactor; 20. Suspended bed reaction zone; 21. Homogeneous slurry inlet; 22. Lower liquid product outlet; 30. Fluidized bed reaction zone; 31. First reaction zone; 32. Second reaction zone; 33. Microsphere catalyst inlet; 34. Microsphere catalyst outlet; 35. Hydrogen inlet; 36. Second catalyst; 37. Third catalyst; 40. Gas-liquid separation zone; 41. Gas outlet; 42. Upper liquid product outlet; 50. Diverter tank; 51. Inner reaction zone; 52. Outer reaction zone; 60. Jacket; 61. Heat transfer oil inlet; 62. Heat transfer oil outlet; 70. Gas distributor; 80. Filter screen. Detailed Implementation

[0020] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0021] It should be noted that when an element is referred to as being "set on" another element, it can be directly on or indirectly on the other element. It should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the invention, "a number" means two or more, unless otherwise explicitly specified.

[0022] Please see Figure 1The biofuel preparation apparatus provided by this invention will now be described. The biofuel preparation apparatus includes a multifunctional hydrogenation reactor 10, whose shell contains, from bottom to top, a suspended bed reaction zone 20, a fluidized bed reaction zone 30, and a gas-liquid separation zone 40. The suspended bed reaction zone 20 has a homogenized slurry inlet 21 and a lower liquid product outlet 22. The fluidized bed reaction zone 30 is internally divided into two series-connected catalyst beds, a first reaction zone 31 and a second reaction zone 32, by three layers of filters 80. The first reaction zone 31 and the second reaction zone 32 each have an independent microsphere catalyst inlet 33, a microsphere catalyst outlet 34, and a hydrogen inlet 35. The gas-liquid separation zone 40 has a gas outlet 41 and an upper liquid product outlet 42. The gas outlet 41 is used to connect to a hydrogen circulation system; the microsphere catalyst outlet 34 is used to connect to a catalyst regeneration system; and the microsphere catalyst inlet 33 is used to connect to the catalyst regeneration system.

[0023] This application provides a biofuel production apparatus. In its actual use, the multifunctional hydrogenation reactor 10 integrates, from bottom to top, a suspended bed reaction zone 20, a fluidized bed reaction zone 30, and a gas-liquid separation zone 40 within its shell. The suspended bed reaction zone 20, located at the bottom, accommodates the raw material slurry and powdered catalyst for preliminary hydrogenation. The fluidized bed reaction zone 30, located in the middle, is internally divided by a filter 80 into two connected beds containing different microsphere catalysts for deep hydrogenation refining. The gas-liquid separation zone 40, located at the top, separates the gas and liquid components from the reaction products. The reactor utilizes an external hydrogen circulation system and a catalyst regeneration system to continuously replenish and recycle hydrogen and the three types of catalysts.

[0024] This design achieves a highly integrated hydrogenation conversion process, from raw material pretreatment to deep refining and product separation, all within a single reactor. This design completely replaces the complex layout of multiple connected devices such as suspended beds, fixed beds / fluidized beds, and separators in traditional processes. This significantly shortens the process flow, simplifies equipment connections and pipelines, and substantially reduces total equipment investment, floor space, and energy losses due to material transport and repeated heating and cooling. Simultaneously, it improves the compactness, safety, and ease of operation of the entire production system.

[0025] The biofuel production apparatus provided in this embodiment, compared with existing technologies, achieves a highly integrated hydrogenation conversion process, from raw material pretreatment to deep refining and product separation, all within a single reactor. This design completely replaces the complex layout of multiple devices connected in series, such as suspended beds, fixed beds / fluidized beds, and separators, in traditional processes. This significantly shortens the process flow, simplifies equipment connection pipelines, and thus significantly reduces the total equipment investment, floor space, and energy loss caused by material transfer and repeated heating and cooling. At the same time, it improves the compactness, safety, and ease of operation of the entire production system.

[0026] In one possible implementation, the aforementioned suspended bed reaction zone 20 adopts, as shown in... Figure 1 The structure shown is described in the following document. Figure 1 The suspended bed reaction zone 20 is equipped with a diversion tank 50, which divides it into an inner reaction zone 51 and an outer reaction zone 52. The homogenized slurry inlet 21 is connected to the bottom of the inner reaction zone 51, and the lower liquid product outlet 22 is located at the bottom of the outer reaction zone 52.

[0027] Specifically, a cylindrical diversion tank 50 is vertically arranged inside the suspended bed reaction zone 20. This diversion tank 50 physically divides the suspended bed reaction zone 20 into a centrally located cylindrical inner reaction zone 51 and an annular outer reaction zone 52 located between the diversion tank 50 and the reactor shell. The homogenized slurry inlet 21 is directly connected to the bottom of the inner reaction zone 51. The bottom sidewall of the outer reaction zone 52 has the lower liquid product outlet 22.

[0028] The splitter tank 50 structure creates a unique reaction path. After the main reaction of the feed slurry in the inner reaction zone 51, a portion can enter the outer reaction zone 52, forming a circulation, which prolongs the reaction time and changes the flow state, promoting a more complete reaction. Simultaneously, the lower liquid product outlet 22 at the bottom of the outer reaction zone 52 allows for the removal of a portion of the appropriately converted liquid product in the early stages of the reaction, preventing excessive degradation and providing additional flexibility for process control. This structure enhances adaptability to high-viscosity, coking-prone feedstocks and optimizes the fluid distribution and reaction process within the reactor.

[0029] In one possible implementation, the aforementioned multifunctional hydrogenation reactor 10 employs, as shown in... Figure 1 The structure shown is described in the following document. Figure 1 The shell of the multifunctional hydrogenation reactor 10 is provided with a jacket 60. The shell sections corresponding to the first reaction zone 31 and the second reaction zone 32 of the suspended bed reaction zone 20 and the boiling bed reaction zone 30 are respectively provided with independent jacket 60 sections. Each jacket 60 section is provided with an independent heat transfer oil inlet 61 and heat transfer oil outlet 62.

[0030] Specifically, a jacket 60 is installed around the metal shell of the multifunctional hydrogenation reactor 10. This jacket 60 is not a single unit, but rather segmented according to the distribution of the internal reaction zones. Specifically, it consists of three segments: a jacket 60 segment covering the shell section of the suspended bed reaction zone 20, a jacket 60 segment covering the shell section of the first fluidized bed reaction zone 31, and a jacket 60 segment covering the shell section of the second fluidized bed reaction zone 32. Each independent jacket 60 segment has a heat transfer oil inlet 61 and a heat transfer oil outlet 62.

[0031] The segmented, independent jacket design 60 enables completely independent temperature control of the slurry bed reaction zone 20, the first fluidized bed reaction zone 31, and the second reaction zone 32. By introducing heat transfer oil at different temperatures and flow rates into different sections of the jacket 60, the temperature of each reaction zone can be precisely stabilized within its optimal process range (e.g., 420°C for the slurry bed, 380°C for the first fluidized bed zone, and 360°C for the second fluidized bed zone). This is crucial for hydrogenation reactions because different reaction stages (such as preliminary cracking deoxygenation and deep refining isomerization) require different optimal reaction temperatures. Independent temperature control maximizes the reaction efficiency and selectivity at each stage, avoiding the increased side reactions or insufficient reaction depth caused by integrated temperature control, and is a key guarantee for obtaining high-quality target products.

[0032] In one possible implementation, the aforementioned fluidized bed reaction zone 30 adopts, as shown in... Figure 1 The structure shown is described in the following document. Figure 1 Gas distributors 70 are provided below the first reaction zone 31 and the second reaction zone 32 of the fluidized bed reaction zone 30. The gas distributors 70 are connected to the hydrogen inlet 35 of the corresponding reaction zone.

[0033] Specifically, in the fluidized bed reaction zone 30, a gas distributor 70 is installed below the lower filter 80 of the first reaction zone 31 and below the middle filter 80 of the second reaction zone 32. The gas distributor 70 is usually a porous tubular or plate structure, and its inlet end is connected to the hydrogen inlet 35 opened on the shell of the corresponding reaction zone through a pipe.

[0034] The function of the gas distributor 70 is to uniformly disperse the hydrogen introduced from the hydrogen inlet 35 into a large number of fine bubbles and distribute them evenly across the entire cross-section of the catalyst bed. This ensures sufficient fluidization of the catalyst particles, forming a stable boiling (expanded) bed state. The uniform hydrogen distribution greatly enhances the mass transfer efficiency between the gas, liquid, and solid phases, enabling the hydrogenation reaction to proceed rapidly and uniformly, preventing incomplete reactions or coking due to insufficient local hydrogen supply. Simultaneously, good fluidization also avoids localized overheating and channeling in the catalyst bed, ensuring stable reactor operation, long catalyst life, and uniform product quality.

[0035] Furthermore, the gas-liquid separation zone 40 is located above the uppermost filter screen 80 and is equipped with a demister inside.

[0036] Please see Figure 2 The present invention also provides a method for preparing biofuel, utilizing a biofuel preparation apparatus and implemented in an environment including a catalyst regeneration system and a hydrogen circulation system, comprising the following steps: S1. Raw material pretreatment: Two or more raw materials are mixed and then filtered, dehydrated, and degassed to obtain mixed raw material oil. S2, Suspended Bed Hydrogenation: The mixed feedstock oil is mixed with the first catalyst and hydrogen to form a homogeneous slurry, which is then preheated and fed into the suspended bed reaction zone 20 for reaction; S3, fluidized bed hydrogenation: The reaction product of step S2 is fed upward into the first reaction zone 31 of the fluidized bed reaction zone 30, where it reacts under the action of the second catalyst 36 and hydrogen; the reaction liquid continues to enter the second reaction zone 32, where it continues to react under the action of the third catalyst 37 and hydrogen to obtain the final reaction liquid. S4. Gas-liquid separation and product separation: The final reaction liquid is separated in the gas-liquid separation zone 40. The separated hydrogen-rich gas is processed by the hydrogen circulation system and then recycled. The separated liquid product is fractionated to obtain biofuel. S5. Catalyst regeneration and recycling: The first catalyst turbid liquid obtained in step S4 is regenerated by the catalyst regeneration system and then recycled; the second catalyst turbid liquid 36 and the third catalyst turbid liquid 37 are periodically discharged from the microsphere catalyst outlet 34, and after being regenerated by the catalyst regeneration system, they are added to the first reaction zone 31 and the second reaction zone 32 respectively through the microsphere catalyst inlet 33.

[0037] Specifically, a biofuel production unit, supported by a catalyst regeneration system and a hydrogen circulation system, executes five core steps in sequence: First, various raw materials are pretreated by mixing, filtering, dehydrating, and degassing; then, the pretreated oil is mixed with powdered catalyst and hydrogen, preheated, and sent to the suspended bed reaction zone 20 for preliminary hydrocracking and impurity removal; the reactants rise into the fluidized bed reaction zone 30, and pass through two beds containing different functional microsphere catalysts for deep hydrorefining; the refined products are separated in the top gas-liquid separation zone 40, the hydrogen-rich gas is recycled, and the liquid products are fractionated to obtain the target fuel; finally, the deactivated catalyst slurry discharged during the reaction is sent to the regeneration system to restore its activity and then recycled back to the corresponding reaction zones.

[0038] This method provides a complete, continuous, efficient, and economical biofuel production process. It fully leverages the advantages of compact integrated units and zoned synergy, perfectly combining feedstock adaptability, deep conversion, precise refining, and resource recycling. Through a process sequence of "pretreatment - preliminary conversion in a suspended bed - deep refining in a fluidized bed," various low-quality oil feedstocks can be efficiently converted into clean fuels. The closed-loop circulation system of catalyst and hydrogen significantly reduces raw material consumption and waste emissions. This method features a short process flow, high operational flexibility, and the ability to flexibly adjust the product structure according to market needs, demonstrating significant technological advancement and economic competitiveness.

[0039] In one possible implementation, the above-mentioned raw materials are used as follows: Figure 2 The structure shown is described in the following document. Figure 2In step S1, the raw materials are two or more of the following: cashew shell oil, jatropha oil, waste cooking oil, animal fat, plant asphalt, and microalgae oil.

[0040] Specifically, in the raw material pretreatment step, the raw materials used are selected from two or more of the following list and mixed together: cashew shell oil (high in phenols), jatropha oil (containing cyclopropylene fatty acids), waste cooking oil (high acid value, containing water and impurities), animal fat (high saturation, high pour point), plant asphalt (high oxygen, high metals, high colloids), and microalgae oil (may contain phospholipids and pigments).

[0041] This limitation clearly defines one of the core advantages of the method of this invention: its strong raw material inclusiveness. It is not designed for any single high-quality raw material, but rather specifically for processing the aforementioned "inferior" or "non-traditional" raw materials with complex compositions, diverse properties, and difficulties in processing using traditional methods. This design allows projects to break free from dependence on a single raw material supply, enabling the utilization of lower-priced and more widely sourced waste oils and non-grain biomass, greatly expanding raw material sources, reducing raw material costs, and enhancing the resilience and sustainability of the industrial supply chain.

[0042] In one possible implementation, the first catalyst described above adopts the structure shown in Figure 2, see [reference]. Figure 2 In step S2, the first catalyst is a micron-sized powder catalyst; in step S3, the second catalyst 36 and the third catalyst 37 are both microspherical particle catalysts.

[0043] Specifically, in step S2, the first catalyst used in the fluidized bed hydrogenation is a micron-sized (particle size 1-100 μm) powder catalyst, such as a Mo-Ni-Co-W ultrafine powder catalyst. In step S3, the second catalyst 36 used in the first reaction zone 31 and the third catalyst 37 used in the third reaction zone are both microspherical particle catalysts with larger particle sizes (0.5-3 mm), such as Ni-Mo / Al2O3, Pt-Pd / SAPO-11, etc.

[0044] The suspended bed catalyst uses ultrafine powder catalysts, whose huge specific surface area allows for thorough dispersion in the feedstock. While exerting hydrogenation activity, it efficiently adsorbs poisons such as metals and alkali nitrogen from the feedstock, acting as a "sacrificial" impurity trap to protect the subsequent expensive microsphere catalysts. The fluidized bed catalyst uses microsphere catalysts, whose larger particle size allows them to be retained by a filter screen, forming a fluidized bed layer. This layer is specifically responsible for intricate reactions such as deep desulfurization, denitrification, and isomerization to obtain high-quality products. The clear division of labor and synergistic action of these two types of catalysts is the key technology enabling the system to stably process inferior feedstocks and produce high-quality products over the long term.

[0045] In one possible implementation, the aforementioned homogeneous slurry is adopted as follows: Figure 2 The structure shown is described in the following document. Figure 2In step S2, the homogenized slurry is preheated to 150-200℃; the reaction conditions for hydrogenation in the suspended bed are: temperature 350-420℃, pressure 15-20MPa, and liquid hourly space velocity 0.5-1.0h. - ¹, Hydrogen-to-oil volume ratio 800-1500:1.

[0046] Specifically, the specific operating parameters for step S2, the suspended bed hydrogenation, are determined as follows: preheating the homogeneous slurry to 150-200℃; controlling the reaction temperature between 350-420℃; controlling the reaction pressure between 15-20 MPa; and controlling the liquid hourly space velocity (LHSV) between 0.5-1.0 h⁻¹. - ¹; the volume ratio of hydrogen to feedstock oil is controlled between 800:1 and 1500:1.

[0047] This parameter range represents the optimal operating window for slurry-bed hydrotreating, determined through extensive experimental optimization. Under these conditions, efficient hydrodeoxygenation, double bond saturation, ring-opening, and selective cracking reactions can be achieved, converting large-molecule oils into smaller-molecule hydrocarbons while minimizing excessive cracking to produce gases and coke. Suitable space velocity and hydrogen-to-oil ratio ensure sufficient reaction time and hydrogen partial pressure, guaranteeing conversion depth and catalyst stability. These conditions form the basis for achieving efficient initial conversion and providing qualified feedstock for subsequent refining stages.

[0048] In one possible implementation, the above-mentioned fluidized bed hydrogenation adopts, as follows: Figure 2 The structure shown is described in the following document. Figure 2 The reaction conditions for hydrogenation in the fluidized bed in step S3 are: temperature 350-400℃ and pressure 15-20MPa.

[0049] Specifically, the operating parameters for step S3, fluidized bed hydrogenation, are determined as follows: the reaction temperature is controlled between 350-400℃; the reaction pressure is controlled between 15-20 MPa. Under these relatively mild conditions, deep purification is achieved through two-stage catalysis.

[0050] This reaction condition range is specifically designed for deep hydrorefining. Under this temperature and pressure, reactions such as hydrodesulfurization, denitrogenation, and olefin and aromatic saturation can be fully carried out, thoroughly removing impurity atoms and ensuring complete product saturation; while avoiding excessive hydrocracking that leads to a decrease in liquid yield. Simultaneously, this temperature range also allows zeolite catalysts (such as SAPO-11) to exert their shape-selective isomerization function, adjusting the degree of branching in the products, thereby directionally optimizing the low-temperature fluidity (e.g., lowering freezing point and pour point) and combustion performance (e.g., improving cetane number and smoke point) of the final fuel product.

[0051] In one possible implementation, see Figure 2In step S4, aviation kerosene products with a distillation temperature range of 150-250℃ and / or biodiesel products with a distillation temperature range of 180-360℃ are obtained by fractionation.

[0052] Specifically, the target products obtained by fractionation in step S4 are: aviation kerosene with a distillation temperature range of 150-250°C, and / or biodiesel with a distillation temperature range of 180-360°C. The aviation kerosene product has a smoke point of not less than 25 mm, a freezing point of not more than -47°C, and an aromatic hydrocarbon volume content of not more than 20%. The biodiesel product has a cetane number between 49 and 90 and a pour point between -10°C and -30°C.

[0053] This definition clearly defines the final product standards achievable by the method of this invention. These indicators are not ordinary fuel standards, but rather point to high-quality, high-value-added clean fuel products. Aviation kerosene meets stringent alternative jet fuel specifications, and biodiesel exhibits excellent combustion performance and low-temperature adaptability. This directly demonstrates the technological advancement and practical value of this invention, indicating that this method and system can stably upgrade inferior biomass feedstocks into commercially viable biofuels that meet advanced international standards, possessing clear market application prospects and competitiveness.

[0054] Example 1, Preparation of aviation kerosene: S1. Raw material pretreatment: Cashew shell oil, waste cooking oil, and animal fat are mixed in a mass ratio of 3:4:3, and then filtered, dehydrated, and degassed to obtain mixed raw material oil, while removing solid impurities and water.

[0055] S2. Suspended Bed Hydrogenation: The mixed feedstock oil obtained in step S1, the first catalyst (molybdenum-nickel-cobalt-tungsten ultrafine powder catalyst, particle size 1-100μm, addition amount 1000ppm based on molybdenum), and hydrogen are mixed to form a homogeneous slurry. After preheating to 150℃, the slurry enters the inner reaction zone 51 of the suspended bed reaction zone 20 at the bottom of the multifunctional hydrogenation reactor 10 through the homogeneous slurry inlet 21. The reaction conditions are controlled as follows: temperature 350℃, pressure 20MPa, liquid hourly space velocity 1.0h. - ¹, The hydrogen-to-oil volume ratio is 1200:1. During the reaction, the powdered catalyst adsorbs metals and basic nitrides from the raw materials. After part of the reaction slurry enters the outer reaction zone 52 to continue the reaction, it is discharged from the lower liquid product outlet 22.

[0056] S3. Fluidized Bed Hydrogenation: The remaining reactants rise into the first reaction zone 31 of the fluidized bed reaction zone 30. Here, the second catalyst 36 (a nickel-molybdenum microsphere catalyst supported on alumina, with a particle size of 0.5-3 mm) undergoes deep hydrodesulfurization, denitrification, and olefin saturation reactions under the action of hydrogen gas (uniformly distributed through hydrogen inlet 35 and gas distributor 70) at a reaction temperature of 380℃ and a pressure of 20 MPa. Subsequently, the reaction liquid continues to rise into the second reaction zone 32, where it undergoes isomerization and aromatic saturation purification reactions under the action of the third catalyst 37 (a platinum-palladium microsphere catalyst supported on SAPO-11 shape-selective molecular sieve, with a particle size of 0.5-3 mm), further optimizing the low-temperature flowability and smoke point of the product at a reaction temperature of 380℃ and a pressure of 20 MPa.

[0057] S4. Gas-Liquid Separation and Product Separation: The final reaction liquid enters the upper gas-liquid separation zone 40. The gas, after being defoamed by a demister, is discharged from gas outlet 41. After condensation, desulfurization, and deammoniation by an external hydrogen circulation system, it becomes hydrogen-rich gas, which is then recycled. The liquid is discharged from the upper liquid product outlet 42 and mixed with the liquid discharged from the lower liquid product outlet 22. The mixture is then fractionated to obtain light naphtha, aviation kerosene (fraction 150-250℃), and tail oil. The obtained aviation kerosene product, after testing, has a smoke point of 32mm, a freezing point of -52℃, and an aromatic content of <10% (volume fraction), demonstrating excellent performance across all indicators.

[0058] S5. Catalyst Regeneration and Circulation: The first catalyst (powder) turbidity obtained from the liquid product separation system is sent to the first catalyst regeneration system for regeneration and reuse. The deactivated second and third catalyst turbidities 37 are periodically discharged from each reaction zone of the fluidized bed through the microsphere catalyst discharge port 34. After being regenerated by their respective regeneration systems, they are replenished to the corresponding reaction zones through the microsphere catalyst inlet 33 to maintain the catalytic activity of the system.

[0059] Example 2, Preparation of biodiesel: S1. Raw material pretreatment: Jatropha curcas oil, microalgae oil and plant asphalt are mixed in a mass ratio of 5:3:2, and then filtered, dehydrated and degassed to obtain mixed raw material oil, while removing solid impurities and water.

[0060] S2. Suspended Bed Hydrogenation: The mixed feedstock oil obtained in step S1, the first catalyst (Mo-Ni powder catalyst, particle size 1-100μm, added at 1000ppm based on molybdenum), and hydrogen are mixed to form a homogeneous slurry. After preheating to 150℃, the slurry enters the inner reaction zone 51 of the suspended bed reaction zone 20 at the bottom of the multifunctional hydrogenation reactor 10 through the homogeneous slurry inlet 21. The reaction conditions are controlled as follows: temperature 390℃, pressure 17MPa, and liquid hourly space velocity 0.8h. -¹, The hydrogen-to-oil volume ratio is 1100:1. During the reaction, the powdered catalyst efficiently adsorbs metals and basic nitrides from the raw materials. After part of the reaction slurry enters the outer reaction zone 52 for further reaction, it is discharged from the lower liquid product outlet 22.

[0061] S3. Fluidized Bed Refining and Hydrogenation: The remaining reactants enter the first reaction zone 31 of the fluidized bed reaction zone 30. Here, the second catalyst 36 (a nickel-molybdenum microsphere catalyst supported on alumina, with a particle size of 0.5-3 mm) undergoes deep hydrodesulfurization, denitrification, and olefin saturation reactions under the action of hydrogen gas (uniformly distributed through hydrogen inlet 35 and gas distributor 70) at a reaction temperature of 360℃ and a pressure of 17 MPa. Subsequently, the reaction liquid continues to enter the second reaction zone 32, where it undergoes alkane refining and moderate cracking reactions under the action of the third catalyst 37 (a nickel-molybdenum microsphere catalyst supported on an alumina-ZSM-5 composite support, with a particle size of 0.5-3 mm), further optimizing the product's cetane number and low-temperature fluidity at a reaction temperature of 340℃ and a pressure of 17 MPa.

[0062] S4. Gas-Liquid Separation and Product Separation: The final reaction liquid enters the upper gas-liquid separation zone 40. The gas, after being defoamed by a demister, is discharged from gas outlet 41. After condensation, desulfurization, and deammoniation by an external hydrogen circulation system, it becomes hydrogen-rich gas, which is then recycled. The liquid is discharged from the upper liquid product outlet 42 and mixed with the liquid discharged from the lower liquid product outlet 22. The mixture is then fractionated to obtain light naphtha, biodiesel (fraction 180-360℃), and tail oil. The resulting biodiesel product, after testing, has a cetane number of 80 and a pour point of -15℃, meeting the requirements for high-quality biodiesel.

[0063] S5. Catalyst Regeneration and Circulation: The first catalyst (powder) turbidity obtained from the liquid product separation system is sent to the first catalyst regeneration system for regeneration and reuse. The deactivated second and third catalyst turbidities 37 are periodically discharged from each reaction zone of the fluidized bed through the microsphere catalyst discharge port 34. After being regenerated by their respective regeneration systems, they are replenished to the corresponding reaction zones through the microsphere catalyst inlet 33 to maintain the catalytic activity of the system.

[0064] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A biofuel production apparatus, characterized in that, include: The multifunctional hydrogenation reactor has the following integrated components arranged from bottom to top inside its shell: The suspended bed reaction zone is equipped with a homogeneous slurry inlet and a lower liquid product outlet; The fluidized bed reaction zone is internally divided into a first reaction zone and a second reaction zone by three layers of filters, which are connected in series to form a catalyst bed. The first and second reaction zones each have independent microsphere catalyst inlet, microsphere catalyst outlet, and hydrogen inlet. The gas-liquid separation zone is equipped with a gas outlet and an upper liquid product outlet. The gas outlet is used to connect to the hydrogen circulation system; the microsphere catalyst outlet is used to connect to the catalyst regeneration system; and the microsphere catalyst inlet is used to connect to the catalyst regeneration system.

2. The biofuel preparation apparatus as described in claim 1, characterized in that, The suspended bed reaction zone is equipped with a diversion tank, which divides it into an inner reaction zone and an outer reaction zone. The homogenized slurry inlet is connected to the bottom of the inner reaction zone, and the lower liquid product outlet is located at the bottom of the outer reaction zone.

3. The biofuel preparation apparatus as described in claim 1, characterized in that, The shell of the multifunctional hydrogenation reactor is equipped with a jacket. The shell sections corresponding to the first and second reaction zones of the suspended bed reaction zone and the fluidized bed reaction zone are respectively equipped with independent jacket sections. Each jacket section is equipped with an independent heat transfer oil inlet and heat transfer oil outlet.

4. The biofuel preparation apparatus as described in claim 1, characterized in that, Gas distributors are provided below the first and second reaction zones of the fluidized bed reaction zone, and the gas distributors are connected to the hydrogen inlets of the corresponding reaction zones.

5. A method for preparing biofuel, characterized in that, The biofuel production apparatus according to any one of claims 1 to 4, implemented in an environment including a catalyst regeneration system and a hydrogen circulation system, includes the following steps: S1. Raw material pretreatment: Two or more raw materials are mixed and then filtered, dehydrated, and degassed to obtain mixed raw material oil. S2, Suspended bed hydrogenation: The mixed feedstock oil is mixed with the first catalyst and hydrogen to form a homogeneous slurry, which is then preheated and fed into the suspended bed reaction zone for reaction; S3, fluidized bed hydrogenation: The reaction product of step S2 is fed upward into the first reaction zone of the fluidized bed reaction zone, where it reacts under the action of the second catalyst and hydrogen; the reaction liquid continues to enter the second reaction zone, where it continues to react under the action of the third catalyst and hydrogen to obtain the final reaction liquid; S4. Gas-liquid separation and product separation: The final reaction liquid is separated in the gas-liquid separation zone. The separated hydrogen-rich gas is processed by the hydrogen circulation system and then recycled. The separated liquid product is fractionated to obtain biofuel. S5. Catalyst regeneration and recycling: The first catalyst turbid liquid obtained in step S4 is regenerated by the catalyst regeneration system and then recycled; the second and third catalyst turbid liquids are periodically discharged from the microsphere catalyst outlet, and after being regenerated by the catalyst regeneration system, they are added to the first and second reaction zones respectively through the microsphere catalyst inlet.

6. The method for preparing biofuel as described in claim 5, characterized in that, The raw materials mentioned in step S1 are two or more of the following: cashew shell oil, jatropha oil, waste cooking oil, animal fat, plant asphalt, and microalgae oil.

7. The method for preparing biofuel as described in claim 5, characterized in that, In step S2, the first catalyst is a micron-sized powder catalyst; in step S3, the second catalyst and the third catalyst are both microspherical particle catalysts.

8. The method for preparing biofuel as described in claim 5, characterized in that, In step S2, the homogeneous slurry is preheated to 150-200℃; the reaction conditions for the suspended bed hydrogenation are: temperature 350-420℃, pressure 15-20MPa, and liquid hourly space velocity 0.5-1.0h. - ¹, Hydrogen-to-oil volume ratio 800-1500:

1.

9. The method for preparing biofuel as described in claim 5, characterized in that, The reaction conditions for the fluidized bed hydrogenation described in step S3 are: temperature 350-400℃ and pressure 15-20MPa.

10. The method for preparing biofuel as described in claim 5, characterized in that, In step S4, aviation kerosene products with a distillation temperature range of 150-250℃ and / or biodiesel products with a distillation temperature range of 180-360℃ are obtained through fractionation.

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