Anti-coking and stable-operation equipment and method for producing aviation fuel and co-producing chemical raw materials from waste biomass

Abstract

The invention discloses anti-coking and stable-operation equipment for producing aviation fuel and co-producing chemical raw materials from waste biomass. Comprising a low-energy-consumption second-level biomass drying coupling pyrolysis quality-divided conversion biomass crude oil unit, a biomass crude oil suspended bed deoxidation upgrading conversion low-oxygen bio-oil unit and a low-oxygen bio-oil molecular fixed bed reconstruction conversion hydrocarbon aviation fuel unit, by arranging a flash reaction hot start mechanism capable of realizing step temperature rise coke suppression and online switching decoking, a coking reaction time point is quickly crossed, a coking position is transferred, and coking risk space-time decoupling and long-period stable operation of a device for producing aviation fuel and co-producing chemical raw materials from waste biomass are realized. A coupling hydrogen and heat self-sustaining operation mode is adopted in the whole process, self-supply of drying heat and upgrading hydrogen is achieved, and the problem that the external source cost is high is solved. The invention also provides an anti-coking and stable-operation method for producing aviation fuel and co-producing chemical raw materials from waste biomass.

Description

Technical Field

[0001] The present invention relates to the emerging field of biomass zero-carbon fuels, and particularly to an apparatus and method for producing aviation fuel and co-producing chemical raw materials from waste biomass with anti-coking and stable operation. Background Art

[0002] The greenhouse gas emissions generated by the aviation industry account for approximately 13% of the total carbon dioxide emissions from all transportation sources. In addition, by 2050, aviation emissions are expected to increase to approximately 1.8 billion tons of carbon dioxide per year, almost twice that of 2019. Therefore, in order to achieve the goal of net-zero carbon emissions by 2050, it is necessary to reduce emissions by approximately 8.2 billion tons of carbon dioxide, which poses a huge challenge to the aviation industry. Compared with other industries, the emission reduction solutions and paths in the aviation industry are relatively limited, and the emission reduction is difficult, making it one of the so-called "difficult-to-reduce emissions" fields. Sustainable aviation fuel, while having a relatively high calorific value and zero-emission characteristics, does not require large-scale transformation of existing infrastructure, aircraft engines, and operation management systems, thus significantly reducing the emission reduction cost. Therefore, it brings new possibilities and prospects for emission reduction in the aviation industry.

[0003] Currently, the main raw materials for sustainable aviation fuel are waste cooking oil, algae, and lipid raw materials, but they still cannot meet the raw material supply required for the preparation of sustainable aviation fuel. Waste biomass such as straw and wood chips is not only a medium for storing solar energy but also follows the principle of "not competing with humans for food and land" and has a zero-carbon attribute. It is expected to be used as a supplementary raw material to replace petroleum in the production of sustainable aviation fuel, contributing to carbon emission reduction in the aviation field. Therefore, it is urgent to produce biomass aviation fuel from waste biomass as a supplementary oil product.

[0004] However, the technology of producing high-value fuels from waste biomass still faces many challenges in the stable operation of bio-oil hydro-upgrading units and the service life of catalysts. Bio-oil is an unstable oil product because of its high oxygen content and a large amount of low-boiling volatile substances. A series of polymerization or polycondensation reactions will occur during high-temperature heating, making the components prone to coking block the reactor bed. It is found that the ebullated bed hydroprocessing technology has good deoxygenation performance for bio-crude oil and can achieve a relatively high level of hydroconversion of oil products. However, bio-crude oil has poor hydrogen solubility and is difficult to quickly disperse and undergo catalytic hydrogenation reactions after entering the reactor, resulting in coking and blockage problems in equipment and pipelines, which affect the long-term stable operation of the unit. Therefore, there is an urgent need for a raw material supply method that helps to inhibit coking at the reactor inlet to avoid blockage of the reactor bed caused by coking at the reactor inlet. On the other hand, there will be strong exothermic during the hydrodeoxygenation process of bio-crude oil in the reactor, and the temperature of the unit is likely to get out of control, resulting in the phenomenon of "temperature runaway", which causes sintering, structural collapse, deactivation, etc. of the active metal components of the catalyst. This will reduce the service life of the catalyst, increase the catalyst preparation cost and the operation loss of the unit, and seriously pose a great safety risk.

[0005] Chinese Patent CN116286067A discloses a method and device for the long-term stable operation of producing gasoline and diesel from biomass. Although this method uses a series of deoxygenation and upgrading devices to overcome the risks of catalyst coking deactivation and "temperature runaway" caused by single-stage reactions. However, the gasoline and diesel produced by this method do not meet the standard requirements of biomass aviation fuel and do not have the technical requirements for directly producing biomass aviation fuel. At the same time, the drying heat energy consumption and a large amount of hydrogen sources required for the hydro-upgrading process are supplied externally, increasing the operating economic cost; due to the high temperature at the reactor inlet, coking losses will occur after the biomass crude oil enters; the investment and operating costs of the ebullated bed catalyst addition and discharge system used are high.

[0006] Chinese Patent CN102732304A discloses a naphtha hydrotreating reaction device and a hydrotreating reaction method for extending the operation cycle. Although a preheating reactor, a coke removal tank and a heating furnace are added at the feed end, effectively extending the hydrotreating operation cycle economically. The disadvantage of this method is that the hydrotreating reactor used includes a pre-hydrotreating reactor and a main hydrotreating reactor. After the reaction, the fouling collectors and coke removal tanks of both reactors need to be cleaned and then put back. Eventually, the number of start-up and shutdown times needs to be increased, which not only prolongs the maintenance time but also increases the operating cost, and still cannot ensure the long-term stable operation of the equipment.

[0007] U.S. Patent US10876056B2 discloses a process and apparatus for hydrotreating heavy oil using a suspension bed. A portion of the oil is mixed with a catalyst to form a mixed oil, and the mixed oil is subjected to first and second shearing in sequence to achieve high dispersion and mixing of the catalyst and the feedstock oil. However, this method is mainly based on hydrothermal cracking and is not suitable for the process requirements of hydrodeoxygenation of pyrolysis oil from biomass, and it is difficult to meet the characteristics of pyrolysis oil from biomass, such as easy coking, high oxygen content, high polarity, and difficulty in mixing with hydrocarbons. The cold wall and the discharge port in the suspension bed reactor will cause fatigue of the equipment alternating stress due to frequent temperature drops and high pressure, reducing the service life of the device.

[0008] Chinese Invention Patent CN112442404A prepares pyrolysis solids and liquids by independently drying, mixing, and pyrolyzing different types of biomass raw materials in different zones. This invention requires zone hot air drying for different biomasses, with high manual sorting costs, large floor area, long time cycle, and high energy consumption. Moreover, the economic benefits of biomass semicoke are far lower than those of biomass aviation fuel.

[0009] In summary, although many methods and apparatuses for biomass drying - pyrolysis, hydrodeoxygenation and upgrading of bio - oil, pyrolysis coupled with hydrotreating for bio - oil production, and hydrotreating coupled with isomerization for biomass fuel production have emerged, no method and apparatus for preparing biomass aviation fuel that can completely solve the problems of reactor coking and blockage, low cost, and high - efficiency long - term stable operation have been found.

[0010] Therefore, in view of the technical problems in the existing simple or complex processes for producing biomass aviation fuel from biomass, there is an urgent need to develop a method and apparatus for preparing biomass aviation fuel with long - term stable operation, heating at an ultra - high speed, shortening the coking reaction time node, decoupling and transferring the coking risk in the reactor, reducing the cost of coke removal; at the same time, reducing the energy loss of the catalyst heat source, extending the service life of the catalyst, breaking through the technical barriers for preparing biomass aviation fuel, and realizing large - scale industrial application. Summary of the Invention

[0011] The object of the present invention is to address the problems in the existing biomass fuel preparation, such as high cost, difficulty in effective long - term stable operation, and inability to meet the requirements of biomass aviation fuel. The present invention provides a device and method for producing aviation fuel from waste biomass and co - producing chemical raw materials, which can not only obtain high - quality biomass aviation fuel, but also has advantages such as low energy consumption and anti - coking, and can operate stably for a long period.

[0012] To achieve the above object, the present invention adopts the following technical solutions.

[0013] The present invention provides a device for producing aviation fuel and co-producing chemical raw materials from waste biomass with anti-coking and stable operation, which includes: a second-level biomass drying coupled with pyrolysis and medium separation to convert biomass crude oil unit, a biomass crude oil suspension bed deoxygenation and quality improvement to convert low-oxygen bio-oil unit, and a low-oxygen bio-oil molecular fixed bed reconstruction to convert hydrocarbon aviation fuel unit;

[0014] The second-level biomass drying coupled with pyrolysis and medium separation to convert biomass crude oil unit is used for second-level drying and coupled heat treatment of biomass to obtain biomass crude oil, pyrolysis gas and pyrolysis carbon; and reform the pyrolysis gas into green hydrogen as a hydrogen source, and both the biomass crude oil and the hydrogen source are input into the biomass crude oil suspension bed deoxygenation and quality improvement to convert low-oxygen bio-oil unit as reaction raw materials;

[0015] The biomass crude oil suspension bed deoxygenation and quality improvement to convert low-oxygen bio-oil unit is used to quickly cross the coking reaction time point, transfer the coking position, and achieve the spatial and temporal decoupling of coking risk; then through the deoxygenation and quality improvement reaction of biomass crude oil, gas-liquid separation, flash evaporation, and oil-water separation to obtain low-oxygen bio-oil, the hydrogen gas obtained from gas-liquid separation is purified and used as a hydrogen source; the heavy oil obtained from flash evaporation is used as a circulating slurry; the organic solution obtained from oil-water separation is reformed to prepare green hydrogen as a hydrogen source;

[0016] The low-oxygen bio-oil molecular fixed bed reconstruction to convert hydrocarbon aviation fuel unit is used to carry out hydro-reconstruction reaction, oil-water separation and fractionation on the low-oxygen bio-oil components to obtain biomass aviation fuel components and biomass naphtha chemical raw materials, the organic solution obtained from oil-water separation is reformed to prepare green hydrogen as a hydrogen source, and the co-produced distillate biomass naphtha obtained from fractionation is used as a hydrogen donor for the biomass crude oil suspension bed deoxygenation and quality improvement to convert low-oxygen bio-oil unit.

[0017] The above-mentioned second-level biomass drying coupled with pyrolysis and medium separation to convert biomass crude oil unit includes a second-level dryer, a second-level pyrolysis reactor, a cyclone separator, a combustion furnace, a cooling tower and a water-gas shift reactor. The second-level dryer is connected to the second-level pyrolysis reactor, and the dried biomass is sent into the second-level pyrolysis reactor for coupled heat treatment reaction to obtain pyrolysis oil gas and pyrolysis carbon. The pyrolysis oil gas and pyrolysis carbon are separated by a cyclone separator, and the separated pyrolysis carbon is returned to the combustion furnace to provide heat for the second-level dryer or / and the second-level pyrolysis reactor; the pyrolysis gas discharged from the cooling tower after passing through the cyclone separator enters the water-gas shift reactor, and then green hydrogen is prepared by a first hydrogen purification device connected to the water-gas shift reactor; the cooled pyrolysis oil is collected by a biomass crude oil collection device.

[0018] In the above-mentioned biomass crude oil suspension bed deoxygenation and quality improvement to convert low-oxygen bio-oil unit, the biomass crude oil suspension bed deoxygenation and quality improvement to convert low-oxygen bio-oil unit includes a biomass crude oil mixing tank, a flash reaction heat startup mechanism, a suspension bed deoxygenation and quality improvement reactor, and a separator assembly; the biomass crude oil mixing tank mixes biomass crude oil, recycled slurry, and hydrogen donor, and then pre-mixes with a hydrogen source and inputs it into the flash reaction heat startup mechanism; the flash reaction heat startup mechanism quickly preheats the mixed material to 200-400 °C, transfers the coking risk to the flash reaction heat startup mechanism, and realizes space-time decoupling; the preheated mixed material undergoes a deoxygenation and quality improvement reaction in the suspension bed deoxygenation and quality improvement reactor; the products obtained from the reaction are separated into oil and water and flash-evaporated through the separator assembly to obtain low-oxygen bio-oil.

[0019] The flash reaction heat startup mechanism includes a flash reaction heat startup furnace group and a high-temperature reheating furnace; the flash reaction heat startup furnace group includes two or more flash reaction heat startup furnaces, which are used to preheat the mixed material to 150-300 °C. Two or more flash reaction heat startup furnaces can simultaneously perform biomass crude oil preheating and coking removal by switching during the parallel operation process, realizing the dual functions of coking inhibition and coking removal; the high-temperature reheating furnace is used to continue preheating the mixed material coming out of the flash reaction heat startup furnace group to 200-400 °C. The flash reaction heat startup furnace, the high-temperature reheating furnace, and the suspension bed deoxygenation and quality improvement reactor form a gradient heating, which can make the raw material reaction more complete and improve the reaction efficiency and reaction degree. In a preferred implementation, the flash reaction heat startup furnace group includes two flash reaction heat startup furnaces. When one group is taken out for coking removal, the other group of flash reaction heat startup furnaces is used to preheat the mixed material, so as to transfer the coking risk without stopping work. The flash reaction heat startup furnace includes a furnace body, heating tubes placed in the furnace body, and electromagnetic induction coils wound around the heating tubes. The heating tubes are designed in a Z-shaped structure, which can further increase the heat exchange area and improve the exchange efficiency. The heating rate of the electromagnetic induction coils is 30-50 °C / s, and the residence time is 3-5 s to achieve efficient material transportation. By heating the mixed material in the heating tubes through the electromagnetic induction coils, the heating rate can be effectively increased, thereby crossing the coking reaction temperature point, avoiding the increase in the amount of carbon deposition in the tubes caused by slow heating, providing high-quality feed, and realizing efficient material transportation. The high-temperature reheating furnace uses a conventional heating furnace, and the energy is fully utilized through two-stage stepwise preheating to increase the local concentration of hydrogen and catalyst.

[0020] Also included in the biomass crude oil mixing tank is a catalyst for deoxygenation and upgrading reaction; the catalyst dosage is controlled by controlling the circulation state of the catalyst in the operating area of the suspension bed deoxygenation and upgrading reactor. The coarse catalyst participates in the internal circulation of the reactor, the fine catalyst participates in the external circulation of the reactor, and the powdered catalyst is separated and discharged; the discharged catalyst is replenished through the biomass crude oil mixing tank; the particle size of the coarse catalyst is 70-100% of the initial catalyst particle size; the fine catalyst is 30-70% (excluding the end values) of the initial catalyst particle size; the powdered catalyst is 0-30% of the initial catalyst particle size, excluding the end value of 0. The initial catalyst is the newly added catalyst that has not participated in the reaction, and the particle size range of the initial catalyst is 10-200 μm.

[0021] Inside the suspension bed deoxygenation and upgrading reactor, from bottom to top in sequence are a raw material inlet, a reaction bed layer, and a reactant outlet; a three-phase cyclone separator is also provided above the reaction bed layer. A ring gap structure is added to the three-phase cyclone separator, and the specific structure can be referred to in CN113816460A. The ring gap structure is used for overflow drainage, and through the pressure difference between the inlet and outlet caused by self-overflow iterative separation, it is used to recover the bio-oil dispersed at the outlet, solving the problem of low separation efficiency caused by more internal circulation flow and short-circuit flow in the cyclone. A spent catalyst replacement port is provided at the horizontal end of the three-phase cyclone separator for replacing the catalyst, reducing the heat source energy consumption lost during the update of the deactivated catalyst, and slowing down the equipment maintenance and loss caused by frequent switching between high and low pressures and alternating stress fatigue.

[0022] The separator assembly includes a hot high-pressure separator, a cold high-pressure separator, a flash tank, and a cold low-pressure separator; the product obtained from the deoxygenation and upgrading reaction is first separated into gas phase and liquid phase by the hot high-pressure separator (since the temperature and pressure of the product entering at this time are relatively high, it is called the hot high-pressure separator); the separated gas phase is cooled by the first cooler and then further separated for hydrogen by the cold high-pressure separator (although the temperature of the product has decreased at this time, the gas pressure is still relatively high, so it is called the cold high-pressure separator here), and the hydrogen is purified by the first hydrogen purification device as a hydrogen source; based on different boiling points, the separated liquid phase is separated into light oil and heavy oil by the flash tank, and the heavy oil is transported to the biomass crude oil mixing tank as a circulating slurry; the light oil obtained by flashing in the flash tank is mixed with the liquid phase separated by the cold high-pressure separator after passing through the second cooler, and the oil phase and water phase are separated by the cold low-pressure separator (at this time, the product pressure needs to be controlled at 1-2.5 MPa), the obtained oil phase is the low-oxygen bio-oil, and the obtained water phase is the organic solution, which is sent to the organic solution reforming hydrogen production reactor, and the hydrogen prepared is purified by the second hydrogen purification device to obtain green hydrogen. The purpose of the flash tank is to separate light oil and heavy oil, with a working temperature of 175-350 °C and a pressure of 1-1.7 MPa; in addition, the catalyst is discharged as discharged oil slag from the flash tank pipeline.

[0023] In a preferred implementation, a part (5 - 10%) of the obtained low - oxygen bio - oil is transported as a circulating slurry to the biomass crude oil mixing tank, and 90 - 95% is transported to the low - oxygen bio - oil molecular fixed - bed reconstruction and conversion to hydrocarbon aviation fuel unit. The part used as the circulating slurry is used to coat the biomass crude oil to prevent reaction coking at the pipeline transportation process and the suspension bed feed inlet.

[0024] In addition, to achieve the replenishment of the catalyst for the deoxygenation and upgrading reaction, a catalyst is also included in the biomass crude oil mixing tank. To enhance the effect of the catalyst, the amount of the circulating slurry can also be controlled to keep the catalyst in a suspended state within the operation range of the suspension bed deoxygenation and upgrading reactor.

[0025] The above - mentioned low - oxygen bio - oil molecular fixed - bed reconstruction and conversion to hydrocarbon aviation fuel unit is used to carry out a hydro - reforming reaction on the low - oxygen bio - oil to obtain biomass aviation fuel components meeting the standards. The low - oxygen bio - oil molecular fixed - bed reconstruction and conversion to hydrocarbon aviation fuel unit includes a fixed - bed molecular reconstruction reactor, a recycle separator, a liquid - phase separator, and a fractionation unit; under the action of the hydrogen source of the first hydrogen purification device, the fixed - bed molecular reconstruction reactor carries out a hydro - reforming reaction on the low - oxygen bio - oil components. The hydrogen separated from the obtained products by the recycle separator is purified by the first hydrogen purification device and then enters the recycle hydrogen compressor, and the separated liquid phase enters the liquid - phase separator to separate the oil phase and the water phase; the oil phase enters the fractionation unit to fractionate out C8 - C 16 hydrocarbon - based biomass aviation fuel and obtain co - produced distillates; the water phase is an organic solution, which is sent to the organic solution reforming and hydrogen - production reactor, and the hydrogen prepared is purified by the second hydrogen purification device to obtain green hydrogen.

[0026] A micro - nano bubble generating device is built in the top of the fixed - bed molecular reconstruction reactor, which is used for the full mixing of green hydrogen and low - oxygen bio - oil, improving the hydrogen - dissolving capacity and mass and heat transfer of biomass pyrolysis oil. The structure of the micro - nano bubble generating device can be referred to CN111298670A.

[0027] The present invention also provides a method for producing biomass aviation fuel, which is carried out according to the following steps by using the above - mentioned equipment for producing aviation fuel and co - producing chemical raw materials from waste biomass with anti - coking and stable operation:

[0028] S1: The waste biomass is dried and subjected to coupled heat treatment by the second - level biomass drying and coupled pyrolysis and mass - separated conversion to biomass crude oil unit to obtain pyrolysis oil - gas and pyrolysis carbon; the pyrolysis oil - gas and pyrolysis carbon are separated by a cyclone separator; the pyrolysis gas generated by cooling the pyrolysis oil - gas is further prepared into green hydrogen as a hydrogen source through a water - gas shift reaction, and the biomass crude oil is obtained while the pyrolysis oil - gas is cooled; the heat released by the combustion of pyrolysis carbon provides heat for biomass drying and coupled heat treatment;

[0029] S2 converts the biomass crude oil into low-oxygen bio-oil through the unit of deoxygenation, upgrading and conversion of biomass crude oil in a suspension bed; premixes the biomass crude oil, hydrogen donor, and recycled slurry, mixes them with the hydrogen source in the pipeline, and then passes them through a flash reaction heat startup mechanism to quickly enter the reaction state. The biomass crude oil undergoes deoxygenation and upgrading reactions to obtain low-oxygen bio-oil; the heavy oil separated during the reaction process is used as the recycled slurry, the separated hydrogen gas is purified and used as the hydrogen source, and the separated organic solution is reformed to prepare green hydrogen as the hydrogen source;

[0030] S3 performs a hydro-upgrading reaction on the components of the low-oxygen bio-oil through the unit of converting low-oxygen bio-oil into hydrocarbon aviation fuel by molecular fixed-bed reconstruction to obtain biomass aviation fuel components; the organic solution separated during the reaction process is reformed to prepare green hydrogen as the hydrogen source, and the co-produced distillate obtained by fractionation is used as the hydrogen donor.

[0031] In the above step S1, the biomass second-level drying is carried out under the conditions of 5 - 20 seconds and normal temperature - 85°C for cyclone dehydration; the temperature of the second-level coupled heat treatment (i.e., second-level pyrolysis) is 400 - 700°C, and the heating rate is between 1000K / s - 10000K / s. The generated biomass crude oil has a water content of less than 30%, and an oxygen content of 30 - 50%; all the pyrolysis carbon is burned to meet the energy requirements of the second-level drying and second-level pyrolysis, among which 30 - 50% is supplied to the second-level dryer, and 50 - 70% is supplied to the second-level pyrolysis reactor.

[0032] In the above step S2, the premixed materials are pressurized and then mixed with the hydrogen source in the pipeline, which helps the mixed materials quickly pass through the flash reaction heat startup furnace group and the high-temperature supplementary furnace and enter the suspension bed deoxygenation and upgrading reactor; and helps the mixed materials quickly enter the reaction state to obtain gas-liquid-solid three-phase reaction raw materials. The hydrogen source used in this step also needs to be used after passing through the circulating hydrogen compressor. The temperature of the deoxygenation and upgrading reaction of the biomass pyrolysis oil is 200°C - 400°C, the reaction pressure is 8 - 15MPa, the volume space velocity is 0.6 - 2.0h -1 、the hydrogen-oil ratio is 400:1 - 1500:1, and the residence time is 1 - 4h. The oxygen content of the obtained product is 0.2 - 1%.

[0033] The catalyst used in the deoxygenation upgrading reaction is hard fine particles with a diameter of 10 - 200 μm (preferably 70 - 150 μm) (such as silicon-based and aluminum-based carriers, and the macroscopic shapes include tooth spherical, columnar, and granular). The active metal supported on the particles is a transition metal element from Group IIIB to Group IIB in the periodic table, or an alloy formed by any combination of two or more of the said transition metal elements. The filling amount of the catalyst fine particles accounts for 20 - 85% of the volume of the suspension bed hydrogenation reactor. Coarse catalyst (70 - 100% of the initial catalyst particle size) is circulated inside the reactor. In the suspension bed reactor, the larger-diameter catalyst is driven by the gas-liquid mixture to flow upward under the mutual cooperation of the cyclone and the annular gap member with a guiding function, forming an internal circulation of the catalyst, which can achieve complete fluidization of the catalyst in the bed layer, improve the desulfurization rate, and reduce the amount of catalyst entrained in the biomass pyrolysis oil; fine catalyst (30 - 70% of the initial catalyst particle size) is circulated outside the reactor. The slightly smaller-diameter catalyst is discharged from the reactor with the low-oxygen bio-oil and enters the pipeline, reducing catalyst loss; powder catalyst (0 - 30% of the initial catalyst particle size) is discharged outside. The discharged catalyst is supplemented through the biomass crude oil mixing tank, and the supplement amount is the same as the discharge amount. The amount of the circulating slurry can be controlled to control the catalyst to be in a suspended state in the operation area of the suspension bed deoxygenation upgrading reactor, and then the amount of the catalyst inside and outside the reactor can be regulated. It can avoid the damage caused by the interaction of high-temperature and high-pressure alternating stress fatigue and creep of the equipment, and extend the operation cycle of the device.

[0034] In the above step S3, the hydrogenation reconstruction reaction temperature of the low-oxygen bio-oil is 150 - 450 °C, the pressure is 5 - 20 MPa, the reaction volume space velocity is 0.25 - 4.0 h -1 , the hydrogen-oil ratio is 400:1 - 1500:1, and the residence time is 1 - 4 h; the final boiling point after reconstruction is 200 - 300 °C, and the proportion of the main product biomass aviation fuel in the total liquid yield is 50 - 60%, which is C8 - C 16 long-chain alkanes, meeting the biomass aviation fuel standard of ASTM D7566 or GB 6537 - 2018. The co-produced distillate is biomass naphtha, and its components with boiling points higher than those of the biomass aviation fuel participate in the cycle as hydrogen donors.

[0035] Compared with the prior art, the equipment and method for producing aviation fuel and co-producing chemical raw materials from waste biomass with anti-coking and stable operation provided by the present invention have the following beneficial effects:

[0036] 1) Construct a full-process coupled hydrogen and heat self-sustaining operation mode to realize the self-supply of the drying heat and upgrading hydrogen required for the conversion process, and overcome the problem of high operation cost in the conventional bio-oil conversion.

[0037] In the biomass crude oil unit with second-level biomass drying coupled with pyrolysis and medium separation conversion, the pyrolysis carbon produced is used as the energy and heat supply material. The green hydrogen produced after water-gas shift and organic solution reforming and purification of the pyrolysis gas is used for deoxygenation, upgrading and reconstruction reactions, realizing the "closed-loop operation" heat source utilization and self-supplied hydrogen mode, and overcoming the problems of high drying cost and high hydrogen usage cost in the conventional process from waste biomass to oil products.

[0038] 2) Set up a flash reaction heat startup mechanism that can stepwise increase the temperature to suppress coking and switch to online coking removal, realizing the spatial and temporal decoupling of coking risk and solving the problem of continuous and stable operation of the device.

[0039] Set up a flash reaction heat startup mechanism for bio-oil reaction, transfer the coking risk point of bio-oil in the reactor to outside the reactor, and realize the spatial decoupling of the reaction core area and the coking risk area; the flash reaction heat startup mechanism has the characteristic of stepwise temperature rise, can quickly cross the coking-prone temperature point and enter the reaction temperature, realizing the temporal decoupling of the bio-oil heating process and the coking process; the flash reaction heat startup mechanism has the ability to switch to coking removal, realizing coking removal without shutting down the device and the temporal decoupling of the continuous operation process and the coking removal and maintenance process of the device; through the comprehensive design of spatial and temporal decoupling of coking risk, solve the problem of continuous and stable operation of the device.

[0040] 3) The present invention realizes the internal circulation of the catalyst by swirling, prolongs the service life of the catalyst, overcomes the problems of high-temperature and high-pressure alternating stress fatigue and creep of the equipment, and ensures the long-term operation of the device.

[0041] By constructing a three-phase cyclone separator and a self-overflowing annular gap component inside the suspended bed deoxygenation and upgrading reactor, the internal circulation of the catalyst by swirling is realized, and the service life of the catalyst is prolonged; the heat source energy consumption caused by catalyst replacement is reduced, and the maintenance time extension caused by the bed pressure drop loss brought by valve jamming, wear and internal leakage is reduced; the problem of low separation efficiency inside the cyclone is solved by constructing the annular gap, improving resource recovery and ensuring the long-term operation of the device. Description of the Drawings

[0042] Figure 1 It is a schematic flow chart of the equipment for producing aviation fuel and co-producing chemical raw materials from waste biomass with anti-coking and stable operation provided by the embodiment of the present invention;

[0043] Figure 2 It is a schematic structural diagram of the flash reaction heat startup furnace group;

[0044] Figure 3 It is a schematic structural diagram of the suspended bed deoxygenation and upgrading reactor;

[0045] Figure 4 It is the change trend of the device operation situation and product yield within 3 months in Example 1;

[0046] Figure 5The operation of the device and the changing trend of product yield within 3 months in Example 2

[0047] Components, parts and numbers in the figure:

[0048] 1. Second-level biomass drying coupled with pyrolysis and medium separation to convert biomass crude oil unit, 11. Second-level dryer, 12. Second-level pyrolysis reactor, 13. Cyclone separator, 14. Combustion furnace, 15. Cooling tower, 16. Water-gas shift reactor, 17. First hydrogen purification device, 18. Biomass crude oil collection device, 19. Recirculating hydrogen compressor, 110. Hydrogen donor storage tank, 111. Heat exchanger;

[0049] 2. Suspension bed deoxygenation and quality improvement of biomass crude oil to convert low-oxygen bio-oil unit, 21. Biomass crude oil mixing tank, 21-1. Circulation pump, 22. Flash reaction heat startup furnace group, 22-1. Raw material mixing pipeline, 22-2. Water vapor passage, 22-3. Flash reaction heat startup furnace A, 22-4. Flash reaction heat startup furnace B, 22-5. Electromagnetic induction coil, 22-6. Mixed material outlet, 23. High-temperature furnace repair, 24. Suspension bed deoxygenation and quality improvement reactor, 24-1. Raw material inlet, 24-2. Reaction bed layer, 24-3. Reactant outlet, 24-4. Three-phase cyclone separator, 24-5. Annular gap structure, 24-6. Spent catalyst replacement port, 25. Hot high-pressure separator, 26. Cold high-pressure separator, 27. Flash tank, 28. Cold low-pressure separator, 29. Organic solution reforming hydrogen production reactor, 210. Water vapor generator; 211. First cooler, 212. Second cooler;

[0050] 3. Fixed bed reconstruction of low-oxygen bio-oil molecules to convert to hydrocarbon aviation fuel unit, 31. Fixed bed molecular reconstruction reactor, 32. Circulation separator, 33. Liquid phase separator, 34. Fractionation unit, 35. Second hydrogen purification device, 36. First heater, 37. Second heater. Detailed implementation mode

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the present invention.

[0052] Example 1

[0053] This example provides a device for producing aviation fuel and co-producing chemical raw materials from waste biomass with anti-coking and stable operation, as Figure 1As shown in the figure, it includes a biomass drying coupled with pyrolysis for medium-fraction conversion of biomass crude oil unit 1, a biomass crude oil suspension bed deoxygenation and upgrading to convert low-oxygen bio-oil unit 2, and a low-oxygen bio-oil molecular fixed bed reconstruction to convert hydrocarbon aviation fuel unit 3. Through the biomass drying coupled with pyrolysis for medium-fraction conversion of biomass crude oil unit 1, biomass is dried at normal or low temperature, and then pyrolyzed at low temperature to produce biomass crude oil, pyrolysis gas and pyrolysis char; the pyrolysis char is all burned for heat supply, and the pyrolysis gas is purified by water-gas shift to produce green hydrogen, which is introduced into the biomass crude oil suspension bed deoxygenation and upgrading to convert low-oxygen bio-oil unit 2. A flash reaction heat start mechanism is set to transfer the coking risk at the reactor inlet. A three-phase cyclone separator is set in the suspension bed deoxygenation and upgrading reactor to achieve long catalyst life and low energy consumption circulation. Finally, in the low-oxygen bio-oil molecular fixed bed reconstruction to convert hydrocarbon aviation fuel unit 3, C8-C 16 Hydrocarbon biomass aviation fuel is co-produced with biomass naphtha as a hydrogen donor, and the process organic solution is reformed to produce hydrogen for long-term cyclic operation.

[0054] (1) Biomass drying coupled with pyrolysis for medium-fraction conversion of biomass crude oil unit

[0055] As Figure 1 shown in the figure, the biomass drying coupled with pyrolysis for medium-fraction conversion of biomass crude oil unit 1 is used for second-level drying and coupled heat treatment of biomass to obtain biomass crude oil, pyrolysis gas and pyrolysis char; and the pyrolysis gas is converted into green hydrogen as a hydrogen source; both the biomass crude oil and the hydrogen source are input into the biomass crude oil suspension bed deoxygenation and upgrading to convert low-oxygen bio-oil unit 2 as reaction raw materials.

[0056] The biomass drying coupled with pyrolysis for medium-fraction conversion of biomass crude oil unit 1 includes a second-level dryer 11, a second-level pyrolysis reactor 12, a cyclone separator 13, a combustion furnace 14, a cooling tower 15, a water-gas shift reactor 16, a first hydrogen purification device 17 and a biomass crude oil collector 18.

[0057] The second-level dryer 11 is connected to the second-level pyrolysis reactor 12, and the second-level pyrolysis reactor 12 is connected to the cyclone separator 13. The solid outlet of the cyclone separator 13 is connected to the inlet of the combustion furnace 14. The outlet of the combustion furnace 14 is respectively connected to the second-level dryer 11 and the second-level pyrolysis reactor 12. The separated pyrolysis char is used as a heat source in the combustion furnace 14 to supply energy to the second-level dryer 11 and the second-level pyrolysis reactor 12.

[0058] The gas outlet of the cyclone separator 13 is connected to the cooling tower 15, and the gas outlet of the cooling tower 15 is connected to the water-gas shift reactor 16 and the biomass crude oil collector 18. Further, the outlet pipeline of the cooling tower 15 is also returned to the cooling tower by the heat exchanger 111. The pyrolysis gas discharged after the separated pyrolysis oil and gas passes through the cooling tower enters the water-gas shift reactor. In the water-gas shift reactor 16, through the water-gas shift reaction, CO2 in the pyrolysis gas is purified to H2 through the water-gas shift reaction, and the obtained green hydrogen is further purified by the first hydrogen purification device 17 and then supplied to the biomass crude oil suspension bed deoxygenation and quality improvement to convert the low-oxygen bio-oil unit 2 and the low-oxygen bio-oil molecular fixed-bed reconstruction to convert the hydrocarbon aviation fuel unit 3.

[0059] The above-mentioned second-level pyrolysis reactor 12 uses a down-flow fluidized bed reactor, and the specific structure can be referred to CN116286067A. The above-mentioned first hydrogen purification device uses a PSA hydrogen purification device.

[0060] (2) Biomass crude oil suspension bed deoxygenation and quality improvement to convert the low-oxygen bio-oil unit

[0061] The biomass crude oil suspension bed deoxygenation and quality improvement to convert the low-oxygen bio-oil unit 2 is used to enable the reaction raw materials to achieve space-time decoupling by quickly entering the reaction state, and then through deoxygenation and quality improvement reactions, gas-liquid separation, flash evaporation, and oil-water separation to obtain low-oxygen bio-oil (oxygen content less than 1%), and the hydrogen obtained from gas-liquid separation is purified and used as a hydrogen source; the heavy oil obtained from flash evaporation is used as a circulating slurry; the organic solution obtained from oil-water separation is reformed to prepare green hydrogen as a hydrogen source.

[0062] In a specific implementation manner, as Figure 1 shown, the biomass crude oil suspension bed deoxygenation and quality improvement to convert the low-oxygen bio-oil unit 2 includes a biomass crude oil mixing tank 21, a flash reaction heat startup mechanism, a suspension bed deoxygenation and quality improvement reactor 24, and a separator assembly.

[0063] The biomass crude oil mixing tank 21 mixes biomass crude oil, circulating slurry, hydrogen donor, and catalyst for deoxygenation and quality improvement reaction, and after passing through the circulating pump 21-1, it is mixed with the hydrogen source and steam and then input into the flash reaction heat startup mechanism. The hydrogen source is provided by the circulating hydrogen compressor 19 connected to the first hydrogen purification device 17. The steam is provided by the steam generator 210 and is mainly used for coke cleaning.

[0064] The flash reaction heat startup mechanism quickly preheats the mixed materials. The flash reaction heat startup mechanism includes a flash reaction heat startup furnace group 22 and a high-temperature supplementary furnace 23 connected in series with it. As Figure 2As shown in the figure, the flash reaction heat start-up furnace group includes two flash reaction heat start-up furnaces, namely flash reaction heat start-up furnace A 22-3 and flash reaction heat start-up furnace B 22-4. The inlets of flash reaction heat start-up furnace A 22-3 and flash reaction heat start-up furnace B 22-4 are both connected to the raw material mixing pipeline 22-1 and the water vapor passage 22-2 connected to the water vapor generator 210. Valves are provided on each connecting pipeline. The raw material mixing pipeline is connected to the recycle hydrogen compressor through a pipeline; the outlets of flash reaction heat start-up furnace A 22-3 and flash reaction heat start-up furnace B 22-4 are both connected to the mixed material outlet 22-6, and valves are provided on the connecting pipelines. Flash reaction heat start-up furnace A 22-3 and flash reaction heat start-up furnace B 22-4 have the same structure, and both include a furnace body, heating tubes placed in the furnace body, and electromagnetic induction coils wound around the heating tubes; the heating tubes are thick round tubes in a Z shape, which is beneficial to increasing the heat exchange area and improving the exchange efficiency. 6-9 groups of electromagnetic induction coils are sleeved on the tubes; by heating through the electromagnetic induction coils, the heating rate can be increased, the coking reaction temperature point can be crossed, the increase in the amount of carbon deposition in the tube caused by slow heating can be avoided, high-quality feed can be provided, and efficient material transportation can be realized. The high-temperature furnace for furnace repair is used to continue preheating the mixed material coming out of the flash reaction heat start-up furnace group. The high-temperature furnace for furnace repair 23 uses a basic heating furnace. The outlet of the high-temperature furnace for furnace repair 23 is connected to the inlet of the suspension bed deoxidation and upgrading reactor 24.

[0065] As Figure 3 shown, inside the suspension bed deoxidation and upgrading reactor 24, from bottom to top are the raw material inlet 24-1, the reaction bed layer 24-2, and the reactant outlet 24-3. Above the reaction bed layer 24-2, a three-phase cyclone separator 24-4 is also provided. The specific structure of the three-phase cyclone separator 24-4 can be referred to in CN113816460A. The added annular gap structure 24-5 on the three-phase separator solves the problem of low separation efficiency caused by more internal circulation flow and short-circuit flow in the cyclone. The horizontal end of the three-phase cyclone separator is provided with a spent catalyst replacement port 24-6 for replacing the catalyst, reducing the heat source energy consumption lost during the renewal of the deactivated catalyst, and slowing down the equipment repair and loss caused by frequent switching between high and low pressures and alternating stress fatigue. The catalyst used in the suspension bed deoxidation and upgrading reactor is 50μm fine particles, and the supported active metals are nickel and molybdenum. The filling amount of the catalyst particles accounts for 35% of the volume of the suspension bed deoxidation and upgrading reactor. By controlling the amount of the circulating slurry, the catalyst is controlled to be in a suspended state in the operation area of the suspension bed deoxidation and upgrading reactor 24. By controlling the amount of the hydrogen source, the hydrogen-oil ratio of the deoxidation and upgrading reaction is controlled.

[0066] The separator assembly includes a hot high-pressure separator 25, a cold high-pressure separator 26, a flash tank 27, and a cold low-pressure separator 28. The product obtained from the deoxygenation and upgrading reaction is first separated into gas and liquid phases by the hot high-pressure separator 25; the separated gas phase is further separated from hydrogen by the first cooler 211 and the cold high-pressure separator 26, and is purified by the first hydrogen purification device 17; the separated liquid phase is separated into light oil and heavy oil by the flash tank, and the heavy oil is circulated back to the biomass crude oil mixing tank 21 as circulating slurry through the bed flow; the light oil obtained by flashing in the flash tank 27 is mixed with the liquid phase separated by the cold high-pressure separator 26 after passing through the second cooler 212, and is separated into an oil phase and a water phase by the cold low-pressure separator 28. The obtained oil phase is the low-oxygen bio-oil, and the obtained water phase is the organic solution. The lower end of the cold low-pressure separator 28 is connected to an organic solution reforming hydrogen production reactor, and the hydrogen obtained by reforming the organic solution in the organic solution reforming hydrogen production reactor is purified by the second hydrogen purification device to obtain green hydrogen.

[0067] In one implementation, a part of the obtained low-oxygen bio-oil is transported to the biomass crude oil mixing tank 21 as circulating slurry through a pipeline, and a part is transported to the low-oxygen bio-oil molecular fixed-bed reconstruction and conversion hydrocarbon aviation fuel unit 3 through a pipeline. Valves are provided on each pipeline.

[0068] The above-mentioned organic solution reforming hydrogen production reactor adopts conventional equipment disclosed in the art, and the specific structure can be referred to (CN 213231513U).

[0069] (3) Low-oxygen bio-oil molecular fixed-bed reconstruction and conversion hydrocarbon aviation fuel unit

[0070] The low-oxygen bio-oil molecular fixed-bed reconstruction and conversion hydrocarbon aviation fuel unit 3 is used to carry out hydro-upgrading reaction, oil-water separation and fractionation on low-oxygen bio-oil to obtain biomass aviation fuel components. The waste liquid obtained from oil-water separation is reformed to prepare green hydrogen as a hydrogen source, and the co-produced distillate obtained by fractionation is used as a hydrogen donor.

[0071] The low-oxygen bio-oil molecular fixed-bed reconstruction and conversion hydrocarbon aviation fuel unit 3 includes a fixed-bed molecular reconstruction reactor 31, a recycle separator 32, a liquid separator 33, and a fractionation unit 34.

[0072] The low-oxygen bio-oil is heated by a heater 36 and then input into the fixed-bed molecular reconstruction reactor 31, and then under the action of the hydrogen source of the first hydrogen purification device 17, a hydro-upgrading reaction is carried out on the low-oxygen bio-oil.

[0073] The product obtained from the fixed-bed molecular reconstruction reactor 31 passes through the recycle separator 32. The separated hydrogen is purified by the first hydrogen purification device 17, and the separated liquid phase enters the liquid separator 33 for oil-water separation; the oil phase enters the fractionation unit 34 to fractionate C8-C 16Hydrocarbon biomass aviation fuel, and obtain the co-produced distillate naphtha; the water phase is the waste liquid, which is sent to the organic solution reforming hydrogen production reactor, and the prepared hydrogen is purified by the second hydrogen purification device 35 to obtain green hydrogen.

[0074] The fixed bed molecular reconstruction reactor 31 uses a fixed bed reactor, and the specific structure can be found in CN 118755495A. In addition, a micro-nano bubble generator is arranged at the top of the fixed bed molecular reconstruction reactor 31 to fully mix green hydrogen and low-oxygen bio-oil, thereby improving the hydrogen solubility and mass transfer and heat transfer of the oil. For the structure of the micro-nano bubble generator, see CN111298670A. The catalyst used in the fixed bed molecular reconstruction reactor 31 is aluminum oxide, and the active metals loaded thereon are nickel, molybdenum and zirconium. The specific surface area of ​​the catalyst is 180m 2 / g.

[0075] The second hydrogen purification device 25 has the same structure as the first hydrogen purification device 17 .

[0076] In this embodiment, biomass is used as raw material, and the above-mentioned waste biomass equipment for producing aviation fuel and co-producing chemical raw materials with stable operation and anti-coking is used to prepare biomass aviation fuel according to the following steps:

[0077] S1 dries the biomass and couples the heat treatment to obtain pyrolysis oil gas and pyrolysis char through the second-level biomass drying coupled pyrolysis fractionation and conversion biomass crude oil unit 1; the pyrolysis oil gas and pyrolysis char are separated by a cyclone separator; the pyrolysis oil gas is cooled to produce pyrolysis gas which is then subjected to a water-gas shift reaction to prepare green hydrogen as a hydrogen source, and the pyrolysis oil gas is cooled to obtain biomass crude oil at the same time; the pyrolysis char combustion releases heat to provide heat for biomass drying and coupled heat treatment.

[0078] In this embodiment, waste straw is used as biomass. The biomass is added from the top of the second-level dryer 11 and dried. The drying time is 8 seconds and the drying temperature is 85°C. The moisture content of the biomass is reduced from 35% to 8%. The dried biomass is discharged from the bottom of the second-level dryer 11 and enters the second-level pyrolysis reactor 12 through the top of the second-level pyrolysis reactor 12. After being heated to 600°C, a rapid pyrolysis reaction occurs. The heating rate of 1000 K / s and the cooling rate of pyrolysis oil and gas of 500 K / s are selected during the pyrolysis process. The pyrolysis carbon and pyrolysis oil and gas generated by pyrolysis are separated by a cyclone separator. The separated pyrolysis carbon directly enters the combustion furnace. A small part (about 30%) of the hot air flow generated in the combustion furnace 14 enters the second-level dryer 1, and most (about 70%) enters the second-level pyrolysis reactor 12. The pyrolysis oil and gas (high-temperature oil and gas) generated by pyrolysis passes through the cooling tower 5 and is cooled to 60°C to obtain bio-crude oil. One part is further cooled to 30°C through the heat exchanger 6 and then returns to the cooling tower to spray the high-temperature oil and gas from the gas-solid cyclone separator 3. The other part of the bio-crude oil obtained by cooling enters the bio-crude oil collection device 9. The properties of the bio-crude oil are shown in Table 1 and Table 2. The pyrolysis gas discharged from the cooling tower is used to produce green hydrogen through the water-gas shift reactor 7. After being purified by the first hydrogen purification device, the green hydrogen enters the suspension bed deoxygenation and upgrading reactor 24 and the fixed bed molecular restructuring reactor 31.

[0079] S2 converts bio-crude oil into low-oxygen bio-oil through the bio-crude oil suspension bed deoxygenation and upgrading conversion low-oxygen bio-oil unit 2; the bio-crude oil, hydrogen donor, and recycled slurry are premixed and mixed with the hydrogen source in the pipeline, and then enter the flash reaction heat start mechanism through the flash reaction heat start mechanism to quickly enter the reaction state. The bio-crude oil undergoes deoxygenation and upgrading reactions to obtain low-oxygen bio-oil; the heavy oil separated during the reaction process is used as the recycled slurry, the separated hydrogen is purified and used as the hydrogen source, and the separated organic solution is reformed to produce green hydrogen as the hydrogen source.

[0080] The bio-crude oil, hydrogen donor, and recycled slurry are mixed in the bio-crude oil mixing tank 12. The mixed material is pressurized by the circulating pump 21-1 and mixed with the hydrogen from the circulating hydrogen compressor 19 in the pipeline, enters the flash reaction heat start furnace A22-3 and is quickly heated to 200°C, then enters the high-temperature supplementary furnace 23 and is preheated to 300°C, and enters the suspension bed deoxygenation and upgrading reactor 24. The mixed material and the spherical catalyst are quickly heated, mixed, and diluted under the high-speed disturbance of the suspension bed deoxygenation and upgrading reactor 24 to carry out deoxygenation and upgrading reactions. The suspension state of the deoxygenation and upgrading reaction catalyst is controlled by controlling the amount of the recycled slurry and making it meet the operation range of the suspension bed reactor. The hydrogen-oil ratio of the deoxygenation and upgrading reaction is controlled by controlling the amount of the circulating hydrogen. In this example, the catalyst is a fine particle spherical catalyst loaded with active metal nickel, and the hydrogen-oil volume ratio is 400:1. The reaction volume space velocity of this example is 0.6 h -1, the reaction pressure is 13.0 Mpa and the reaction temperature is 300 °C. The low-oxygen bio-oil product after the deoxygenation and quality improvement reaction passes through the hot high-pressure separator 25. The gas phase enters the cold high-pressure separator 26 after passing through the first cooler 211, and the generated cold high-pressure hydrogen is recycled and enters the first hydrogen purification device 17; the liquid phase of the low-oxygen bio-oil is introduced into the flash tank 27 (operating temperature 300 °C, pressure 1.25 MPa). The flash tank 27 separates light oil, heavy oil and waste catalyst. The heavy oil is returned to the biomass crude oil mixing tank 12 through bed fluidization circulation as circulating slurry; the other outlet is connected to the second cooler 212 and the cold low-pressure separator 28 (pressure controlled at 2 Mpa). The lower end of the cold low-pressure separator 28 is connected to the organic solution reforming hydrogen production reactor 29. What is separated from the cold low-pressure is the low-oxygen bio-oil. At this time, the low-oxygen bio-oil is directly input into the low-oxygen bio-oil molecular fixed-bed reconstruction and conversion hydrocarbon aviation fuel unit 3.

[0081] S3 performs a hydro-upgrading reaction on the low-oxygen bio-oil through the low-oxygen bio-oil molecular fixed-bed reconstruction and conversion hydrocarbon aviation fuel unit 3 to obtain biomass aviation fuel components; the waste liquid separated during the reaction process is reformed to prepare green hydrogen as a hydrogen source, and the co-produced distillate obtained by fractionation is used as a hydrogen donor.

[0082] In this embodiment, for the reconstruction reaction, the hydrogen-oil ratio is 800:1. The hydro-upgrading catalyst in this embodiment adopts a toothed spherical alumina-based catalyst, and the reaction volume space velocity of this embodiment is 0.8 h -1 , the reaction pressure is 15.0 MPa and the reaction temperature is 300 °C. The oxygen in the low-oxygen bio-oil is removed to 0.1%, and the sulfur content is less than 10 ppm.

[0083] In this embodiment, the biomass aviation fuel preparation process can achieve stable operation for 3 months, and the deoxygenated and reconstructed biomass aviation fuel products for 3 months still meet the sustainable aviation fuel standards. The overall energy consumption of the whole process is reduced by 40%, and the total yield of biomass aviation fuel is increased to 85%. Figure 4 The figure shows the product yield trend within 3 months. It can be seen from the figure that the equipment for producing aviation fuel and co-producing chemical raw materials from waste biomass with anti-coking and stable operation provided by the present invention can achieve long-term stable operation. Even if coking is removed, it does not affect the equipment operation.

[0084] Table 1 Properties of straw crude oil and low-oxygen straw oil generated by the deoxygenation and quality improvement reaction

[0085]

[0086] Table 2 GCMS result analysis of straw crude oil and low-oxygen straw oil

[0087]

[0088] Table 3 Result analysis of straw aviation fuel

[0089]

[0090] Tables 1 and 2 give the component and performance analysis results of bio-crude oil and low-oxygen bio-oil produced by the deoxygenation and upgrading reaction. It can be seen from the tables that the quality of the bio-oil product is significantly improved, the yields of substances such as alcohols, esters, ketones, and aldehydes are significantly reduced, while the total amounts of alkanes and aromatic hydrocarbons are significantly increased, which is conducive to the subsequent restructuring reaction.

[0091] Table 3 gives the partial composition analysis results of the restructured bio-aviation fuel. The proportion of the main product bio-aviation fuel in the total liquid yield is 50 - 60%, containing C8 - C 16 alkanes, among which the proportion of aromatic hydrocarbons is 47.68 - 49.73%, meeting the bio-aviation fuel standards of ASTM D7566 or GB 6537 - 2018.

[0092] Example 2

[0093] In this example, compared with Example 1, the flash reaction hot start furnace group 22 is not set, and there is only one high-temperature supplementary furnace. Other operating conditions and process flows are the same as those in Example 1. Table 4 shows the comparison of the properties of low-oxygen bio-oil between Example 2 and Example 1, and Table 5 shows the GCMS result analysis of the low-oxygen bio-oil between Example 2 and Example 1. Figure 5 It is the comparison of the yield changes of bio-aviation fuel between Example 2 and Example 1.

[0094] Table 4 Comparison of the Properties of Low-Oxygen Bio-Oil between Example 2 and Example 1

[0095]

[0096] Table 5 GCMS Result Analysis of Low-Oxygen Bio-Oil between Example 2 and Example 1

[0097]

[0098] After continuous operation for three months, the comparison between the low-oxygen bio-oil obtained in this example and that in Example 1 is shown in Tables 4 and 5. Compared with Example 1, the process set in Example 2 lacks the flash reaction heat startup furnace group to transfer the raw material coking. Therefore, there is tar carbon deposition blockage in the suspension bed deoxidation and upgrading reactor and the pipeline, and shutdown is required for coke cleaning, resulting in a shortened device operation cycle. Since the mixed materials are not heated in a gradient manner, the reaction of the mixed materials is incomplete, and the reaction efficiency and degree are lower than those in Example 1. As can be seen from Tables 4 and 5, the quality of the bio-oil product obtained without setting the flash reaction heat startup furnace group is significantly lower than that in Example 1. The calorific value of the bio-oil decreases from 45 MJ / kg to 35 MJ / kg, the oxygen content increases from 0.1 wt.% to 20.4 wt.%, the yields of substances such as alcohols, esters, ketones, and aldehydes increase, while the total amount of alkanes and aromatic hydrocarbons decreases from 74.34% to 54.36%. The quality of the bio-oil is poor, and it is difficult to carry out subsequent reconstruction reactions. Figure 5 It can be seen that the device cannot operate stably for a long period, and shutdown for maintenance due to coking is required for 10 - 20 days.

[0099] Example 3

[0100] In this example, compared with Example 1, the annular gap structure with a guiding function is not set in the suspension bed deoxidation and upgrading reactor, and the catalyst cannot achieve internal circulation. Other operating conditions and process flows are the same as those in Example 1. Some of the catalysts discharged from the suspension bed deoxidation and upgrading reactor 24 are severely deactivated, the catalyst consumption increases, the material cost and the valve maintenance cost increase by 20%, which is not conducive to engineering scale-up, and the operation cycle is reduced from 3 months to 2 months. This is attributed to the fact that the catalyst does not participate in the swirling internal circulation, the catalyst life is shortened, the heat source energy consumption caused by catalyst replacement increases, the equipment needs to withstand the interactive influence damage mode of high-temperature and high-pressure alternating stress fatigue and creep, which increases the bed pressure drop loss caused by valve jamming, wear and internal leakage, resulting in an extended maintenance time, and the high-quality conversion of the biomass aviation fuel product cannot be achieved.

[0101] Example 4

[0102] In this example, compared with Example 1, recycled green hydrogen is not used in the fixed bed molecular reconstruction reactor 31. Other operating conditions and process flows are the same as those in Example 1. Table 6 shows the comparison of various parameters of the biomass aviation fuel between Example 4 and Example 1.

[0103] Table 6 Comparison of various parameters of the biomass aviation fuel between Example 4 and Example 1

[0104]

[0105] The comparison between the bio-aviation fuel obtained in this example and that in Example 1 is shown in Table 6. Compared with Example 1, in the process set in Example 4, the low-oxygen bio-oil enters a fixed-bed molecular restructuring reactor without recycling green hydrogen for deep hydrogenation. Since the restructuring reaction is highly exothermic, during the production process of the fixed-bed molecular restructuring reactor, there will be a situation where the heat release rate of the exothermic reaction is greater than the heat transfer, resulting in out-of-control device temperature and severe temperature runaway, which causes the collapse of the structure of the active component of the catalyst and sintering deactivation. As shown in Table 6, the freezing point of the bio-aviation fuel obtained in Example 4 is higher than that in Example 1. This may be because the device temperature of the fixed-bed molecular restructuring reactor is unstable, and after the catalyst is sintered, carbon deposition occurs, blocking the active sites of the catalyst, resulting in slow reaction and poor restructuring effect, reduced product yield, and difficulty in achieving long-term stable operation. The operation cycle is shortened from 3 months in Example 1 to 2 months.

[0106] Example 5

[0107] In this example, compared with Example 1, the second-level biomass drying coupled with pyrolysis and medium-separated conversion of biomass crude oil unit 1, the biomass crude oil suspension bed deoxygenation and upgrading to convert low-oxygen bio-oil unit 2, and the low-oxygen bio-oil molecular fixed-bed restructuring to convert hydrocarbon aviation fuel unit 3 operate independently. The waste hydrogen and organic sewage generated by the deoxygenation, upgrading and restructuring systems are directly discharged, resulting in a significant increase in the supply of external hydrogen sources (hydrogen, hydrogen donors) throughout the process. Compared with Example 1, the energy consumption of the whole process increases by 23%.

[0108] The processing cost of the waste bio-aviation fuel product in this example is about 6,000 yuan / ton of oil product. The external drying heat energy supply cost of the second-level biomass drying coupled with pyrolysis and medium-separated conversion of biomass crude oil unit 1 is 600 yuan / ton of oil product. When the biomass crude oil suspension bed deoxygenation and upgrading to convert low-oxygen bio-oil unit 2 and the low-oxygen bio-oil molecular fixed-bed restructuring to convert hydrocarbon aviation fuel unit 3 operate independently, the external hydrogenation hydrogen cost is 1,500 yuan / ton of oil product. Compared with Example 1, the whole-process cost increases by 35%, mainly due to the external supply of drying heat energy and hydrogen source.

[0109] In summary, the present invention provides a device and method for producing aviation fuel and chemical raw materials from waste biomass with stable operation and resistance to coking. The biomass is dried and coupled with pyrolysis reaction at a temperature below 100°C in seconds to achieve low-energy pyrolysis to prepare green hydrogen and biomass crude oil; reforming pyrolysis oil gas and tar to purify hydrogen, and supply hydrogen source for deoxygenation, quality improvement and reconstruction; the flash reaction hot start furnace group preheats the biomass crude oil, circulating slurry and hydrogen source, and transfers the coking risk from the reactor inlet to the flash reaction hot start furnace group in an operation mode that can step temperature rise to suppress coking and switch online to remove coking, thereby achieving temporal and spatial decoupling of coking risk and solving the hidden dangers caused by device blockage. The catalyst with a larger diameter in the suspended bed deoxidation and upgrading reactor can be circulated in the catalyst under the cooperation of the cyclone and the annular gap component with guiding function, so as to overcome the problems of high temperature and high pressure alternating stress fatigue and creep of the equipment, extend the life of the catalyst, and ensure the long-term operation of the device; the fixed bed reactor for biomass aviation fuel is used to suppress the temperature rise, so as to achieve long-term stable operation of the device; the hydrogen generated in the process is purified and transported to the circulating hydrogen compressor for recycling, so that the device can achieve a 30% reduction in energy consumption in the whole process, a 35% reduction in product processing costs, and an increase in the total yield of biomass aviation fuel to 85%, and the device can operate stably for 3 months. The biomass aviation fuel product meets the bio-based aviation fuel component of ASTM7566 or GB 6537-2018 standards, and the carbon footprint analysis of the product has an emission of less than 28.2g CO2 / GJ, which meets the EU's sustainable fuel standards.

[0110] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A device for producing aviation fuel and chemical raw materials from waste biomass with stable operation and anti-coking, characterized in that: include: A biomass drying-coupled pyrolysis fractionation conversion unit for biomass crude oil in seconds (1), a biomass crude oil suspension bed deoxygenation upgrading conversion unit for low-oxygen bio-oil (2), and a low-oxygen bio-oil molecule fixed bed reconstruction conversion unit for hydrocarbon aviation fuel (3); The second-level biomass drying coupled pyrolysis fractionation and conversion biomass crude oil unit (1) is used to obtain biomass crude oil, pyrolysis gas and pyrolysis carbon; and the pyrolysis gas is reformed to convert green hydrogen as a hydrogen source, and the biomass crude oil and the hydrogen source are both input as reaction raw materials into the biomass crude oil suspension bed deoxygenation and upgrading conversion low-oxygen bio-oil unit (2); The biomass crude oil suspension bed deoxygenation and upgrading conversion low-oxygen bio-oil unit (2) is used to quickly cross the coking reaction time point, transfer the coking position, and achieve the temporal and spatial decoupling of the coking risk; then the low-oxygen bio-oil is obtained through the biomass crude oil deoxygenation and upgrading reaction, gas-liquid separation, flash evaporation, and oil-water separation, and the hydrogen obtained by gas-liquid separation is purified and used as a hydrogen source; the heavy oil obtained by flash evaporation is used as a circulating slurry; the organic solution obtained by oil-water separation is reformed to prepare green hydrogen as a hydrogen source; The low-oxygen bio-oil molecule fixed bed reconstruction and conversion hydrocarbon aviation fuel unit (3) is used to carry out hydrogenation reconstruction reaction, oil-water separation and fractionation on the low-oxygen bio-oil component to obtain biomass aviation fuel component and biomass naphtha chemical raw material; the organic solution obtained by oil-water separation is reformed to prepare green hydrogen as a hydrogen source; the co-produced distillate biomass naphtha obtained by fractionation is used as a hydrogen supplier for the biomass crude oil suspended bed deoxygenation and upgrading conversion low-oxygen bio-oil unit (2).

2. The equipment for producing aviation fuel and chemical raw materials from waste biomass with stable operation and anti-coking according to claim 1 is characterized in that: The second-level biomass drying coupled pyrolysis fractionation and conversion biomass crude oil unit (1) comprises a second-level dryer (11), a second-level pyrolysis reactor (12), a cyclone separator (13), a combustion furnace (14), a cooling tower (15) and a water-gas shift reactor (16); the second-level dryer (11) is connected to the second-level pyrolysis reactor (12), and the dried biomass is sent to the second-level pyrolysis reactor for coupled heat treatment reaction to obtain pyrolysis oil gas and pyrolysis char, the pyrolysis oil gas and pyrolysis char are separated by a cyclone separator, and the separated pyrolysis char is returned to the combustion furnace, thereby providing heat for the second-level dryer and / or the second-level pyrolysis reactor; the separated pyrolysis oil gas passes through the cooling tower and the discharged pyrolysis gas enters the water-gas shift reactor, and then is passed through a first hydrogen purification device (17) connected to the water-gas shift reactor to prepare green hydrogen; the cooled pyrolysis oil is the bio-crude oil, which is collected by a bio-crude oil collection device (18).

3. The equipment for producing aviation fuel and chemical raw materials from waste biomass with anti-coking and stable operation according to claim 1 is characterized in that: The biocrude oil suspension bed deoxygenation upgrading and conversion low-oxygen bio-oil unit (2) comprises a biocrude oil mixing tank (21), a flash reaction hot start mechanism, a suspended bed deoxygenation upgrading reactor (24) and a separator assembly; the biocrude oil mixing tank (21) mixes the biocrude oil, the circulating slurry and the hydrogen supply agent, and then premixes with the hydrogen source and inputs the mixture into the flash reaction hot start mechanism, thereby transferring the coking risk to the flash reaction hot start mechanism and realizing time-space decoupling; the preheated mixed material undergoes a deoxygenation upgrading reaction in the suspended bed deoxygenation upgrading reactor (24); the reaction product is separated into oil and water and flash evaporated through the separator assembly to obtain low-oxygen bio-oil.

4. The equipment for producing aviation fuel and chemical raw materials from waste biomass with stable operation and anti-coking according to claim 3 is characterized in that: The flash reaction hot start mechanism comprises a flash reaction hot start furnace group (22) and a high temperature supplementary furnace (23); the flash reaction hot start furnace group comprises two or more flash reaction hot start furnaces, which are used to preheat the mixed material to 150-300°C. The two or more flash reaction hot start furnaces can simultaneously preheat the biomass crude oil and switch to decoking through a parallel structure operation process, thereby realizing the dual functions of inhibiting coking and decoking; the high temperature supplementary furnace is used to continue preheating the mixed material from the flash reaction hot start furnace group to 200-400°C, and fully utilize the energy through two-stage preheating.

5. The equipment for producing aviation fuel and chemical raw materials from waste biomass with anti-coking and stable operation according to claim 3 is characterized in that: The biomass crude oil mixing tank (21) also includes a catalyst for deoxygenation and upgrading reaction; the amount of catalyst is controlled by controlling the circulation state of the catalyst in the operating domain of the suspended bed deoxygenation and upgrading reactor (24); the coarse catalyst participates in the circulation inside the reactor, the fine catalyst participates in the circulation outside the reactor, and the powder catalyst is separated and discharged; the discharged catalyst is replenished through the biomass crude oil mixing tank (21); the particle size of the coarse catalyst is 70-100% of the particle size of the initial catalyst; the particle size of the fine catalyst is 30-70% of the particle size of the initial catalyst (excluding the end value); the particle size of the powder catalyst is 0-30% of the particle size of the initial catalyst, excluding the end value 0.

6. The equipment for producing aviation fuel and chemical raw materials from waste biomass with stable operation and anti-coking according to claim 1 or 3, characterized in that: The interior of the suspended bed deoxidation and upgrading reactor (24) is provided with a raw material inlet (24-1), a reaction bed layer (24-2) and a reactant outlet (24-3) from bottom to top; a three-phase cyclone separator (24-4) and an annular gap (24-5) are also provided above the reaction bed layer (24-2).

7. The equipment for producing aviation fuel and chemical raw materials from waste biomass with anti-coking and stable operation according to claim 3 is characterized in that: The separator assembly in the biomass crude oil suspension bed deoxygenation and upgrading conversion low-oxygen bio-oil unit (2) comprises a hot high-pressure separator (25), a cold high-pressure separator (26), a flash tank (27) and a cold low-pressure separator (28); the product obtained from the deoxygenation and upgrading reaction is first separated into a gas phase and a liquid phase by the hot high-pressure separator (25); the separated gas phase is further separated into hydrogen by the cold high-pressure separator (26), and is purified by a first hydrogen purification device (17) as a hydrogen source; based on different boiling points, The separated liquid phase is separated into light oil and heavy oil through a flash tank, and the heavy oil is transported to the biomass crude oil mixing tank (21) as a circulating slurry; the light oil obtained by flash evaporation in the flash tank (27) is mixed with the liquid phase separated by the cold high-pressure separator (26), and the oil phase and the water phase are separated by a cold low-pressure separator (28). The obtained oil phase is low-oxygen bio-oil, and the obtained water phase is organic solution, which is sent to the organic solution reforming hydrogen production reactor. The prepared hydrogen is purified by a second hydrogen purification device to obtain green hydrogen.

8. The equipment for producing aviation fuel and chemical raw materials from waste biomass with stable operation and anti-coking according to claim 1 or 7, characterized in that: The low-oxygen bio-oil molecule fixed-bed reconstruction and conversion unit (3) comprises a fixed-bed molecular reconstruction reactor (31), a circulating separator (32), a liquid phase separator (33) and a fractionation unit (34); the fixed-bed molecular reconstruction reactor (31) performs a hydrogenation reconstruction reaction on the low-oxygen bio-oil component under the action of a hydrogen source of a first hydrogen purification device (17); the hydrogen separated by the circulating separator (32) is purified by the first hydrogen purification device; the separated liquid phase enters the liquid phase separator (33) to separate the oil phase and the water phase; the oil phase enters the fractionation unit to fractionate the C8-C 16 Hydrocarbon biomass aviation fuel, and obtain a co-produced distillate; the water phase is an organic solution, which is sent to an organic solution reforming hydrogen production reactor, and the prepared hydrogen is purified by a second hydrogen purification device (35) to obtain green hydrogen.

9. A method for producing aviation fuel and chemical raw materials from waste biomass with stable operation and anti-coking, characterized in that: The equipment for producing aviation fuel and co-producing chemical raw materials from waste biomass with anti-coking and stable operation according to any one of claims 1 to 8 is carried out according to the following steps: S1 uses a second-level biomass drying coupled pyrolysis fractionation conversion biomass crude oil unit (1) to dry and couple heat treatment the waste biomass to obtain pyrolysis oil gas and pyrolysis carbon; the pyrolysis oil gas and pyrolysis carbon are separated by a cyclone separator; the pyrolysis oil gas is cooled to produce pyrolysis gas, which is then subjected to a water-gas shift reaction to prepare green hydrogen as a hydrogen source, and the pyrolysis oil gas is cooled to obtain biomass crude oil; the pyrolysis carbon is burned and released to provide heat for biomass drying and coupled heat treatment; S2 converts the biocrude oil into low-oxygen bio-oil through a biocrude oil suspension bed deoxygenation and upgrading conversion low-oxygen bio-oil unit (2); premixes the biocrude oil, hydrogen supply agent, and circulating slurry, and mixes them with a hydrogen source in a pipeline, and then quickly enters a reaction state through a flash reaction hot start mechanism, and the biocrude oil is deoxygenated and upgraded to obtain low-oxygen bio-oil; the heavy oil separated in the reaction process is used as a circulating slurry, the separated hydrogen is purified and used as a hydrogen source, and the separated organic solvent is reformed to prepare green hydrogen as a hydrogen source; S3 conducts a hydrogenation reconstruction reaction on the low-oxygen bio-oil component through a low-oxygen bio-oil molecule fixed bed reconstruction conversion hydrocarbon aviation fuel unit (3) to obtain a biomass aviation fuel component; the organic solution separated during the reaction is reformed to prepare green hydrogen as a hydrogen source, and the co-produced distillate obtained by fractionation is used as a hydrogen supply agent.

10. The method for producing aviation fuel and chemical raw materials from waste biomass with anti-coking and stable operation according to claim 9, characterized in that: The temperature of the deoxygenation and upgrading reaction of biomass crude oil is 200℃-400℃, the reaction pressure is 8-15MPa, and the volume space velocity is 0.6-2.0h -1 , the hydrogen-oil ratio is 400:1-1500:1, the residence time is 1-4h, and the oxygen content of the obtained product is 0.2-1%; The hydrogenation and reconstruction reaction temperature of low-oxygen bio-oil is 150-450℃, the pressure is 5-20MPa, and the reaction volume space velocity is 0.25-4.0h -1 , hydrogen-oil ratio is 400:1-1500:1, residence time is 1-4h; the final distillation point after molecular reconstruction is 200-300°C, the main product is biomass aviation fuel, accounting for 50-60% of the total yield of biomass crude oil, and the co-produced distillate is biomass naphtha chemical raw material.

Images