Device, method and system for online circulating, grading and recycling of catalyst in suspended bed hydrogenation reactor

Abstract

The invention belongs to the technical field of biomass energy equipment, provides a device, a method and a system for online circulation grading recycling of a catalyst in a suspended bed hydrogenation reactor, and aims to solve the problems that the catalyst in the suspended bed hydrogenation reactor is low in storage amount and easy to coke and inactivate, and three-phase separation in the reactor cannot be realized. According to the device, the method and the system provided by the invention, the coarse catalyst can be remained in the reactor to cyclically participate in the reaction through in-device cyclic grading recycling of the coarse catalyst, so that the addition amount of a fresh catalyst is reduced, and the catalyst storage amount of a suspended bed hydrogenation reaction system is increased; through external circulation grading return of the fine catalyst, the utilization rate of the fine catalyst is improved, and meanwhile, coking caused by excessive temperature rise of a reactor outlet due to enrichment of the fine catalyst at the outlet is avoided; the powdery catalyst which is easily coked is removed, so that the long-period stable operation of the reactor is facilitated; and the inner-outer folding structure is arranged, high-speed secondary fluid collides with short-circuit flow in a front-face mode, and the separation precision is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of biomass energy equipment technology, specifically relating to a device, method, and system for online recycling and staged reuse of catalysts in a suspended bed hydrogenation reactor. Background Technology

[0002] Biomass energy is energy provided by living plants in nature. These plants store solar energy using biomass as a medium, making it a renewable energy source. It is estimated that the energy stored in biomass is twice the total energy consumption of the world. A suspended bed hydrogenation reactor is a highly efficient reactor used for the hydrogenation conversion of inferior feedstocks such as heavy oil, residual oil, or coal tar. The carbon neutrality advantages of biomass energy are reflected in the following aspects: ① Closed-loop carbon cycle, reducing net carbon emissions: Biomass energy originates from organic matter such as plants, crop residues, forestry waste, and animal manure. During their growth, these biomasses absorb carbon dioxide (CO2) from the atmosphere through photosynthesis and convert it into organic matter (such as cellulose and lignin). When these biomasses are used in energy utilization processes such as combustion, fermentation, or gasification, the amount of CO2 released is equal to the amount absorbed during their growth, forming a closed carbon cycle. Therefore, theoretically, the carbon emissions from biomass energy offset the carbon absorption, resulting in zero net emissions. ② Renewable and widely available resources: Biomass energy has a wide range of raw material sources, including agricultural and forestry waste (straw, sawdust), energy crops (miscanthus, switchgrass), and organic waste (kitchen waste, manure), all of which are renewable. ③ Stable and controllable energy supply, compensating for intermittent nature: Biomass energy can be stored in the form of solid fuels (pellets, briquettes), liquid fuels (bioethanol, biodiesel), or biogas, allowing for flexible allocation and compensating for the intermittent nature of wind and solar energy. Furthermore, biomass power plants can operate stably 24 hours a day, making them suitable as a baseload power source for the grid and increasing the proportion of renewable energy. It is worth emphasizing that biomass is currently the only liquid fuel alternative with promising industrial applications and is receiving increasing attention. According to data from the International Energy Agency (IEA), biomass energy accounts for 55% of global renewable energy consumption, making it one of the largest non-fossil energy sources currently.

[0003] Catalytic hydrogenation of biomass pyrolysis oil refers to the process of introducing hydrogen (H2) into a reaction system under specific temperature and pressure conditions using a suitable catalyst to alter the molecular structure of the feedstock and convert it into liquid fuel. The resulting liquid fuel is primarily a hydrocarbon product, consistent with existing petroleum-based products, and can be directly used in existing engine systems without major modifications, helping to alleviate the energy crisis and reduce environmental pollution. For biomass pyrolysis oil, catalytic hydrogenation mainly aims to remove oxygen, as the presence of oxygen not only reduces the energy density of the bio-oil but also leads to higher acidity, easily causing equipment corrosion and storage instability.

[0004] Currently, the main problem with catalytic hydrogenation of biomass pyrolysis oil is its inability to achieve stable operation over long periods. Generally, continuous reaction time is a crucial indicator of the stability and efficiency of a catalytic process. Its operating cycle is influenced by various factors, including catalyst activity, stability, reaction conditions, and the properties of the feedstock. The primary reason is that catalysts are prone to deactivation during use due to carbon buildup clogging catalyst channels and metal particle sintering, which significantly reduces catalyst activity and selectivity. Furthermore, biomass pyrolysis oil contains a large amount of oxygen and has a complex composition, including carboxylic acids, aldehydes, alcohols, ketones, esters, ethers, phenols, and furans, making it susceptible to polymerization reactions, coking, and catalyst deactivation, which are very difficult to treat effectively. In biomass oil hydrodeoxygenation, most research focuses on extending continuous reaction time through feedstock pretreatment and improving catalyst stability, while designing the internal structure of the reactor is rarely considered. Theoretically, introducing internal components to improve fluid distribution and reduce coking caused by localized overheating could further extend the stable operating cycle of the reactor, showing promising development prospects. Therefore, breakthroughs in the design of the reactor's internal structure are urgently needed.

[0005] The catalytic hydrogenation process for biomass pyrolysis oil mainly revolves around fluidized bed hydrogenation reactors and suspended bed hydrogenation reactors. Chinese invention patent CN114672337B discloses a method for the hydrodeoxygenation of bio-oils using bimetallic nitride catalysts. This method uses bio-oils as raw materials and employs a molybdenum-based bimetallic nitride catalyst in a fixed-bed reactor to directly catalytically hydrogenate and deoxygenate bio-oils with high oxygen content to produce clean fuels with high calorific value, achieving a conversion rate of 90-98%. However, this method uses a fixed-bed hydrogenation reactor, and the catalyst activity gradually decreases after a period of operation, requiring shutdown and replacement of the catalyst packing. It cannot operate stably for long periods. Chinese invention patent CN110028985A discloses a method for preparing high-quality fuel oil and / or chemical feedstocks from biomass bio-oils. This method uses a fluidized bed hydrogenation reactor, where bio-oil and catalyst are in a fully mixed state, which can mitigate the condensation and coking of bio-oils to a certain extent. Furthermore, Chinese invention patent CN116286067B discloses a method and apparatus for long-term stable operation of biomass-to-gasoline and diesel production. The apparatus includes a biomass second-level non-phase change drying-pyrolysis system for producing bio-oil (I), a bio-oil hydrodeoxygenation system for producing deoxygenated liquid (II), and a deoxygenated liquid hydrorefining system for producing gasoline and diesel (III). Through online activation of the catalyst inside / outside the reactor, coupled with a two-step hydrodeoxygenation-hydrorefining process, it overcomes the coking problem in the hydrodeoxygenation process, achieving long-term stable operation of the apparatus. However, neither of these invention patents considers the safety risks associated with online catalyst addition and removal in fluidized bed hydrotreating reactors. Because the catalyst in a fluidized bed hydrotreating reactor is added and removed online, frequent addition and removal under high temperature and high pressure conditions causes alternating stress on the catalyst addition and removal tanks, making the equipment prone to fatigue failure. Simultaneously, the catalyst wears on the sealing surface of the high-pressure addition and removal valves during the addition and removal process. After multiple additions and removals, the high-pressure addition and removal valves may fail to close completely, posing a risk of high pressure escalating into low pressure. The high-pressure equipment in fluidized bed hydrogenation processes mainly includes high-pressure pumps, heat exchangers, separators, compressors, high-pressure vessels, high-pressure pipelines, valves, and a number of supporting safety devices. These components are diverse and operate under harsh conditions (typically a design temperature of 500℃ and a design pressure as high as 32MPa). These stringent operating conditions place high demands on material selection, manufacturing precision, and maintenance, resulting in high investment costs for high-pressure equipment. Therefore, researchers have focused on the relatively lower-cost fluidized bed hydrogenation process.

[0006] Suspended bed hydrotreating is a hydrotreating process primarily based on hydrothermal cracking. Large molecular hydrocarbons in the feedstock undergo cracking reactions under hydrogen, high temperature, and high pressure to generate smaller molecular hydrocarbons. The catalyst typically acts as a coke carrier, its purpose being to carry the coke produced during the reaction out of the reactor. To facilitate the removal of coke from the reactor, suspended bed hydrotreating reactors are often hollow shell structures, allowing the catalyst to pass through the reactor in one go without circulating within the reactor, thus extending the operating cycle of the unit and reducing production costs. However, this also results in low catalyst reserves within the suspended bed hydrotreating reactor, poor deoxygenation, desulfurization, and denitrification capabilities, and an inability to effectively process biomass pyrolysis oil with high oxygen content. Chinese invention patent CN100340643C discloses a method for treating inferior heavy oil or residual oil. One advantage of this invention is that it recycles the tail oil from the suspended bed hydrotreating process back to the solvent deasphalting unit, enabling the recycling of expensive catalyst active metals, reducing the amount of fresh catalyst added, and increasing the catalyst reserves in the suspended bed hydrotreating reaction system, which is beneficial for suppressing coking during the process. Therefore, it is urgent to increase the catalyst content in suspended bed hydrogenation reactors to adapt to the processing of biomass pyrolysis oil. Chinese invention patent application CN117285962A discloses a coal tar suspended bed hydrogenation reactor based on micro-interface enhancement. This reactor mainly improves reaction efficiency by adding cold hydrogen to control temperature and suppress coking, and by using a cyclone atomizer to enhance gas-liquid-solid three-phase mixing within the reactor. However, it lacks a three-phase separation device, and the separation of the catalyst from the liquid product requires subsequent processing. Currently, it is considered to draw on the application of cyclone fields in fluidized bed hydrogenation reactors to solve the problem of the inability to achieve three-phase separation within the suspended bed hydrogenation reactor.

[0007] In hydrocyclones of suspended bed hydrogenation reactors, a phenomenon known as "short-circuit flow" also exists. This refers to the phenomenon where some of the fluid entering the hydrocyclone (or entrained dispersed phase particles) fails to undergo sufficient rotational motion or residence time within the separation chamber for effective separation, instead escaping directly and rapidly from the hydrocyclone outlet. The presence of short-circuit flow directly reduces separation efficiency. Currently, researchers mainly try to reduce short-circuit flow by optimizing the design of overflow pipe dimensions and insertion depth, changing the material inlet form, and adding guide plates. Chinese invention patent CN104190563A discloses a single-unit multi-stage grading and sorting small-cone angle hydrocyclone, proposing the use of overflow pipes of different lengths and diameters, coaxially mounted sequentially, to achieve multi-stage grading and sorting of materials with different particle sizes and densities. However, the narrow gaps between the multi-stage overflow pipes easily cause coarse particles to clog the interior. Chinese invention patent CN107619276B discloses an ultra-small diameter hydrocyclone and its manufacturing method, proposing to set a rectangular cross-section flow stabilizing channel at the feed inlet; Chinese invention patent CN213611952U discloses a hydrocyclone that uses an internal spiral plate instead of a hollow barrel top plate, and short-circuit flow is discharged through a spiral drain hole; Chinese invention patent CN219400522U discloses a hydrocyclone for the classification of fine-grained light minerals, proposing that the material enters the hydrocyclone through a spiral feed. Although the above three invention patents can reduce the phenomenon of short-circuit flow, their structures are relatively complex, and the hydrocyclone manufacturing process is difficult. Chinese invention patent CN208407365U discloses a hydrocyclone that proposes to set a cover in the lower section of the overflow pipe, so that the short-circuit flow is far away from the overflow pipe opening, but the volume of this rotating body is large, which greatly reduces the effective space for material swirling separation and limits the material processing efficiency. Chinese invention patent CN118477765B discloses a high-precision classifying cyclone separator, proposing to set an umbrella-shaped guide plate at the bottom of the overflow pipe to guide coarse particles that enter the vicinity with the short-circuit flow to the outer cyclone region. However, this passive guidance method has limited effect on suppressing short-circuit flow. Moreover, due to the existence of the boundary layer (a thin flow layer in which the viscous force of the fluid closely adheres to the surface of the object and the fluid velocity is the slowest, and particles tend to accumulate in the boundary layer), the passive guidance method for short-circuit flow, no matter how the flow is guided, always has a boundary that cannot be separated from the guide structure. This part of the boundary layer is still prone to short-circuit flow. Therefore, it can only reduce short-circuit flow, but cannot fundamentally avoid it.

[0008] In summary, to address the issues of low catalyst content, easy coking and deactivation, inability to achieve three-phase separation within the reactor, and inability to avoid short-circuit flow in suspended bed hydrogenation reactors, there is an urgent need in the field to develop a hydrogenation reactor and its application method that can overcome the aforementioned defects of the prior art. Summary of the Invention

[0009] This invention provides a method, apparatus, and system for online recycling and staged reuse of catalysts in a suspended bed hydrogenation reactor, thereby solving the problems existing in the prior art.

[0010] The technical solution adopted by the present invention to solve its technical problem is: a device for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor, including a three-phase cyclone separator installed inside the pressure-bearing shell of the reactor, and a secondary cyclone separator installed outside the pressure-bearing shell of the reactor; the three-phase cyclone separator is connected to the secondary cyclone separator through a pipeline; The three-phase cyclone separator includes a separator body, a first-stage cyclone separation component, and a second-stage cyclone separation component, which are coaxially arranged and nested together in sequence. The primary cyclone separation assembly is used to achieve primary cyclone separation of the crude catalyst in the catalyst; the primary cyclone separation assembly includes a primary cyclone separation guide tube and two or more cyclone-generating guide vanes; The secondary cyclone separation assembly is used to achieve secondary cyclone separation of the crude catalyst in the catalyst; the secondary cyclone separation assembly includes a secondary cyclone separation guide tube and two or more cyclone plates; The swirling guide vane is disposed in the annular channel between the separator body and the primary swirling separation guide tube, and is fixedly connected to both; the swirling plate is disposed circumferentially along the axis of the secondary swirling separation guide tube at the lower end of the inner wall of the secondary swirling separation guide tube. The secondary cyclone separator is used to separate the fine catalyst and discharge the powdered catalyst. The top and bottom of the secondary cyclone separator are respectively provided with discharge ports. The bottom discharge port is connected to the lower part of the reactor pressure shell through a pipe.

[0011] Furthermore, the top of the reactor pressure shell is provided with a gas phase outlet, and the bottom of the reactor pressure shell is provided with a gas-liquid-solid mixed phase inlet; the three-phase cyclone separator is located below the gas phase outlet inside the reactor pressure shell; a gas-liquid-solid distributor is also provided inside the reactor pressure shell, located above the gas-liquid-solid mixed phase inlet.

[0012] Furthermore, the separator body includes a straight cylindrical section a, a conical section a, and an underflow pipe that are coaxially connected from top to bottom. The outer wall of the straight cylindrical section a is connected to the inner wall of the reactor pressure shell through two or more first connecting parts, and a check cone is provided at the lower end of the underflow pipe.

[0013] Furthermore, the primary cyclone separator guide tube includes a straight cylindrical section b, a conical section b, and an outlet pipe coaxially connected from bottom to top; the inner wall of the straight cylindrical section b is connected to the outer wall of the secondary cyclone separator guide tube via a second connector; the outer wall of the straight cylindrical section b is connected to the inner wall of the straight cylindrical section a via swirl-generating guide vanes; the outlet pipe includes a vertical gas phase outlet end and a horizontal liquid phase outlet end; the liquid phase outlet end is connected to the feed inlet of the secondary cyclone separator via a pipeline.

[0014] Furthermore, the upper end of the straight section b is lower than the upper end of the straight section a, the lower end of the straight section b is higher than the lower end of the straight section a, and the inward fold angle α of the lower end of the straight section b is 20 to 40°. The upper end of the secondary cyclone separator guide tube is lower than the upper end of the straight section b, the lower end of the secondary cyclone separator guide tube is lower than the lower end of the straight section b, and the outward fold angle α′ of the lower end of the secondary cyclone separator guide tube is 20 to 40°.

[0015] Furthermore, the inner diameter Da of the straight section b is 60-80% of the inner diameter D of the straight section a; The inner diameter D0 of the secondary cyclone separator guide tube is 70-90% of the inner diameter Da of the straight section b; The height difference between the axis of the liquid phase outlet of the three-phase cyclone separator and the upper end of the straight section a is h1, where h1 is 20-40% of the inner diameter Dn of the pressure-bearing shell of the reactor; The fluidization height of the suspended bed hydrogenation reactor is higher than the upper end of the straight section a, and the height difference between the two is h2, where h2 is 5 to 20% of the inner diameter Dn of the reactor's pressure shell.

[0016] Furthermore, the separation accuracy of the secondary cyclone separator is 2–50 μm.

[0017] This invention also provides a method for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor, which is carried out using the above-mentioned apparatus for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to the following steps: S1 crude catalyst internal circulation primary cyclone separation and reuse: After a portion of the liquid-solid-gas three-phase mixture in the suspended bed hydrogenation reactor is discharged from the gas phase outlet of the suspended bed hydrogenation reactor, the remaining portion undergoes primary cyclone separation from top to bottom through the primary cyclone separation component of the three-phase cyclone separator. The separated crude catalyst flows out of the three-phase cyclone separator along the inner wall of the separator body and returns to the suspended bed hydrogenation reactor to continue participating in the reaction. S2 crude catalyst internal circulation two-stage cyclone separation and reuse: The liquid-solid mixed phase after primary hydrocyclone separation undergoes secondary hydrocyclone separation from bottom to top through the secondary hydrocyclone separation component of the three-phase hydrocyclone separator. The separated crude catalyst flows out of the three-phase hydrocyclone separator along the annular channel between the primary and secondary hydrocyclone separation guide pipes and returns to the suspended bed hydrogenation reactor to continue participating in the reaction. The remaining material in the three-phase hydrocyclone separator is led out of the suspended bed hydrogenation reactor as the liquid crude product through the pipe connecting the three-phase hydrocyclone classifier and the secondary hydrocyclone separator. S3 fine catalyst external circulation cyclone separation and reuse, and powdered catalyst discharge: The crude liquid product is separated into fine catalysts by an external secondary hydrocyclone separator. The fine catalysts re-enter the suspended bed hydrogenation reactor to continue participating in the reaction. The remaining material in the secondary hydrocyclone separator is discharged as liquid product, thereby removing the powdered catalyst retained in the discharged liquid product.

[0018] Furthermore, the particle size range of the fresh catalyst introduced into the suspended bed hydrogenation reactor is 10~200μm; the particle size of the coarse catalyst is 70%~100% of the particle size of the fresh catalyst; the particle size of the fine catalyst is 30%~70% of the particle size of the fresh catalyst; and the particle size of the powdered catalyst is less than 30% of the particle size of the fresh catalyst.

[0019] This method can separate most of the crude catalyst within the reactor, reducing the amount of fresh catalyst added, increasing the catalyst reserves in the suspended bed hydrogenation reactor system, and saving energy consumption for system depressurization and pressurization, thus reducing the system's operating energy consumption. Moreover, the staged return of fine catalyst improves catalyst utilization and avoids the enrichment of fine catalyst at the outlet of the suspended bed hydrogenation reactor, which could cause excessive temperature rise at the outlet and lead to coking. In addition, powdered catalysts have a larger specific surface area and higher reactivity, making them more likely to become coking particles. Therefore, removing this coking-prone substance from powdered catalysts is beneficial for the long-term stable operation of the reactor.

[0020] The present invention also provides a system for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor, comprising at least two catalyst online recycling and staged reuse devices used in series in stages; the liquid phase crude product of the first stage catalyst online recycling and staged reuse device is desolidified by a second stage hydrocyclone separator, and its top outlet is connected to the gas-liquid-solid mixed phase inlet of the next stage catalyst online recycling and staged reuse device through a pipeline.

[0021] Furthermore, the liquid level difference h3 between any two adjacent online circulating stage catalyst recycling units is greater than the friction loss by 0.3 to 2 m.

[0022] The above-mentioned liquid phase crude product includes coarse and fine catalysts, fine catalysts and powdered catalysts; the above-mentioned liquid phase product includes powdered catalysts and a small amount of fine catalysts.

[0023] The beneficial effects of this invention are: (1) By setting up a combination of primary and secondary cyclone separation, most of the crude catalyst is recycled within the reactor, which reduces the amount of fresh catalyst added, increases the catalyst storage capacity of the suspended bed hydrogenation reaction system, and saves energy consumption for system depressurization and pressurization, thus reducing the system's operating energy consumption.

[0024] (2) The fine catalyst is returned to the external circulation stage, which improves the utilization rate of the catalyst and avoids the accumulation of fine catalyst at the outlet, which causes excessive temperature rise at the reactor outlet and causes coking; while the powdered catalyst that is prone to coking is discharged and leaves the reaction system, which is conducive to the long-term stable operation of the reactor.

[0025] (3) Under the acceleration effect of the inner folding structure and the guiding effect of the outer folding structure, the high-speed secondary fluid directly impacts the short-circuit flow, destroying the boundary layer of the guiding structure in the form of active guiding, fundamentally and completely eliminating the short-circuit flow, thereby effectively blocking coarse particles from entering the inner swirling flow region and greatly improving the separation accuracy. Attached Figure Description

[0026] Figure 1 This is a cross-sectional view of the device for online recycling and staged reuse of catalyst in the suspended bed hydrogenation reactor of the present invention; Figure 2 for Figure 1 Schematic diagram of a three-phase cyclone separator; Figure 3 This diagram shows the partial dimensional relationships between the reactor pressure-bearing shell and the separator body, the first-stage cyclone separator guide tube, and the second-stage cyclone separator guide tube of the three-phase separator. Figure 4 This is a schematic diagram showing the flow direction of the gas-liquid-solid mixed phase in a three-phase cyclone separator. Figure 5 This is a schematic diagram of the system for online recycling and staged reuse of catalyst in the suspended bed hydrogenation reactor used in Experimental Example 1 of the present invention; Figure 6 This is a schematic diagram of the system for online recycling and staged reuse of catalyst in the suspended bed hydrogenation reactor used in Experimental Example 2 of the present invention; The diagram is labeled as follows: 1. Reactor pressure-bearing shell; 11. Gas phase outlet; 12. Gas-liquid-solid mixed phase inlet; 2. Three-phase cyclone separator; 21. Separator body; 211. Straight section a; 212. Conical section a; 213. Underflow pipe; 22. First-stage cyclone separation assembly; 221. First-stage cyclone separation guide pipe; 2211. Straight section b; 2212. Conical section b; 2213. Outlet pipe; 222. Swirl-generating guide vane; 2 3. Secondary cyclone separation assembly; 231. Secondary cyclone separation guide pipe; 232. Cyclone plate; 3. Secondary cyclone separator; 4. Gas-liquid-solid distributor; 5. First connecting piece; 6. Check cone; 7. Second connecting piece; 100. First suspended bed hydrogenation reactor; 101. First liquid phase crude product outlet pipe; 102. First and second cyclone separators; 103. Air compressor; 104. First liquid phase product outlet pipe a; 105. 106. First booster pump, 200. First liquid product outlet pipe b, 201. Second suspended bed hydrogenation reactor, 202. Second liquid crude product outlet pipe, 203. Second secondary cyclone separator, 204. Circulation tank, 205. Water pump, 206. First mixing tank, 300. Third suspended bed hydrogenation reactor, 301. Third liquid crude product outlet pipe, 302. Third secondary cyclone separator, 303. Third liquid product outlet pipe a, 304. Second booster pump, 305. Third liquid product outlet pipe b, 400. Fourth suspended bed hydrogenation reactor, 401. Fourth liquid crude product outlet pipe, 402. Fourth secondary cyclone separator, 403. Fourth liquid product outlet pipe, 404. Separator, 405. Air cooler, 406. Second mixing tank, 407. Heating furnace, 408. Hydrogen compressor. Detailed Implementation

[0027] The following is in conjunction with the appendix Figure 1-6 Examples 1-3 and Experimental Examples 1-2 provide a detailed description of the present invention.

[0028] First, it should be noted that the term "about" as used herein refers to ±10%; the terms "comprising," "including," "having," and their variations indicate "including but not limited to"; the terms "upper," "lower," "top," "bottom," "inner," "outer," etc., indicating orientation or positional relationships are only for ease of description and do not indicate or imply that the device or component 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 present invention; when the term "more" indicates a quantity, it usually refers to a quantity of three or more, for example, "a plurality of" usually refers to three or more; the term "crude liquid product" refers to a liquid-solid phase substance with a small amount carried out by the crude catalyst, for example, the amount carried out by the catalyst of 70-100% of the equivalent diameter of the fresh catalyst is less than 0.1 μg / g; the term "liquid phase product" refers to a liquid phase substance with a small amount carried out by the fine catalyst, for example, the amount carried out by the catalyst of 30-70% of the equivalent diameter of the fresh catalyst is less than 0.1 μg / g. Below 0.1 μg / g; the terms "large bubbles" and "small bubbles" are two relative concepts. "Large bubbles" usually refer to bubbles that can burst under inertia before the gas-liquid-solid three-phase mixture enters the gas-liquid-solid three-phase separator, and their diameter is usually above 5 mm; "small bubbles" refer to other bubbles in the gas-liquid-solid three-phase mixture that do not belong to "large bubbles"; the expression "mainly composed of or constitutes" can also be interpreted as containing structural components not mentioned in the sentence; the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships, for example: A and / or B, which can indicate: A alone, A and B simultaneously, and B alone. In addition, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] As used herein, the term "optionally" means "provided in some embodiments and not in others." Any particular embodiment of the invention may include several "optional" features unless these features conflict. Unless otherwise stated, all percentages and parts of matter expressed herein are by weight.

[0030] Example 1

[0031] This embodiment details a device for online catalyst recycling and staged reuse in a suspended bed hydrogenation reactor:

[0032] like Figure 1 As shown, the device for online recycling and staged reuse of catalyst in the suspended bed hydrogenation reactor includes a three-phase cyclone separator 2 installed inside the reactor pressure shell 1, and a secondary cyclone separator 3 installed outside the reactor pressure shell 1; the three-phase cyclone separator 2 is connected to the secondary cyclone separator 3 through a pipeline.

[0033] Understandably, the three-phase cyclone separator 2 is used to perform two separations and reuse of the crude catalyst in the pressure shell 1 of the reactor, and the secondary cyclone separator 3 is used to separate and reuse the fine catalyst discharged from the three-phase cyclone separator 2, while removing the powdered catalyst.

[0034] Specifically, for example Figure 1 As shown, the suspended bed hydrogenation reactor includes a pressure-bearing shell 1. The top of the pressure-bearing shell 1 has a gas phase outlet 11, and the bottom has a gas-liquid-solid mixed-phase inlet 12. A gas-liquid-solid distributor 4 is also installed above the gas-liquid-solid mixed-phase inlet 12. A three-phase cyclone separator 2 is located below the gas phase outlet 11, and a secondary cyclone separator 3 is located outside the pressure-bearing shell 1.

[0035] More specifically, the three-phase cyclone separator 2 includes a separator body 21, a primary cyclone separation component 22, and a secondary cyclone separation component 23, which are coaxially arranged and sequentially nested together; wherein, the primary cyclone separation component 22 is used to achieve primary cyclone separation of the crude catalyst in the catalyst; and the secondary cyclone separation component 23 is used to achieve secondary cyclone separation of the crude catalyst in the catalyst.

[0036] More specifically, in combination Figure 2 As shown, the separator body 21 includes a straight cylindrical section a211, a conical section a212, and an underflow pipe 213 coaxially connected from top to bottom. The straight cylindrical section a211, the conical section a212, and the underflow pipe 213 are integrally formed. The outer wall of the straight cylindrical section a211 is connected to the inner wall of the reactor pressure shell 1 by two or more first connecting parts 5. The first connecting parts 5 can be connecting rods or connecting blocks. In order to stably fix the three-phase cyclone separator 2 inside the reactor pressure shell 1, the present invention preferably fixes the straight cylindrical section a211 to the inner wall of the reactor pressure shell 1 by welding.

[0037] The primary cyclone separation assembly 22 includes a primary cyclone separation guide pipe 221 and two or more swirl-generating guide vanes 222. An annular channel is formed between the primary cyclone separation guide pipe 221 and the separator body 21 to allow the gas-liquid-solid three-phase mixture to enter the three-phase cyclone separator 2. The swirl-generating guide vanes 222 are used to spirally guide the gas-liquid-solid three-phase mixture entering from the upper end of the annular channel between the primary cyclone separation guide pipe 221 and the separator body 21, providing the necessary centrifugal force for three-phase separation, achieving acceleration and directional movement of the fluid and catalyst particles, thereby realizing primary cyclone separation within the crude catalyst separator. Furthermore, combined with… Figure 2As shown, the primary cyclone separator guide tube 221 includes a straight cylindrical section b2211, a conical section b2212, and an outlet tube 2213 coaxially connected from bottom to top. The inner wall of the straight cylindrical section b2211 is connected to the outer wall of the secondary cyclone separator guide tube 231 via a second connector 7, and the outer wall of the straight cylindrical section b2211 is connected to the inner wall of the straight cylindrical section a211 via a swirl-forming guide vane 222. The second connector 7, like the first connector 5, can be a connecting plate or a connecting rod, and the connection method is preferably welding. The outlet tube 2213 includes a vertical gas phase outlet end and a horizontal liquid phase outlet end; the liquid phase outlet end is connected to the feed inlet of the secondary cyclone separator 3 via a pipe. The swirl-generating guide vane 222 is surrounded at a certain angle in the annular channel between the first-stage swirl separation guide tube 221 and the straight section a211. Specifically, the two ends of the swirl-generating guide vane 222 are fixed to the inner wall of the straight section a211 and the outer wall of the straight section b2211, respectively.

[0038] It should be noted that, considering the inclination angle of the swirl-generating guide vane 222 is the main influencing factor in generating centrifugal force, which determines the magnitude of the fluid tangential velocity; the swirl-generating guide vane 222 is a twisted blade, and its inclination angle is characterized by the angle between the inner edge of the swirl-generating guide vane 222 near the axis of the separator body 21 and the axis of the separator body 21; since an inclination angle less than 45° will lead to an increase in the axial velocity and a decrease in the tangential velocity of the fluid, failing to meet the basic centrifugal force conditions required for catalyst particle separation; and an inclination angle greater than 65° will lead to a decrease in the axial velocity and an increase in the tangential velocity of the fluid, although the catalyst particle separation conditions are met, it will lead to an increase in the overall pressure drop of the reactor and an increase in energy consumption; therefore, the preferred inclination angle of the swirl-generating guide vane 222 is 45-65°, and more preferably 50°, 55°, or 60°. Furthermore, in order to increase the centrifugal force generated by the swirl-generating guide vane 222 to achieve a better swirling guiding effect, the structure of the swirl-generating guide vane 222 is preferably a helical blade.

[0039] The secondary cyclone separation assembly 23 includes a secondary cyclone separation guide tube 231 and two or more cyclone plates 232. The cyclone plates 232 are arranged circumferentially around the axis of the secondary cyclone separation guide tube 231 at the lower end of the inner wall of the secondary cyclone separation guide tube 231, and the outer diameter of the outer ring formed by the cyclone plates 232 is the same as the inner diameter of the secondary cyclone separation guide tube 231. This allows a portion of the liquid-solid mixed phase near the center of the secondary cyclone separation guide tube 231 to move upward along the secondary cyclone separation guide tube 231 under the action of the internal cyclone flow of the cyclone plates 232, thereby realizing secondary cyclone separation in the crude catalyst.

[0040] Specifically, the swirl plate 232 has blades with a twisted fan-shaped structure; the blades are positioned low near the axis and high away from the axis, forming a centripetal rotation guide. The outer ends of the blades are inclined in the direction of fluid rotation, forming a "guide slope" to ensure that the fluid spirals upward along the blades. In this invention, the angle (inclination angle) between the lower edge of the swirl plate 232 and the axis of the secondary swirl separation guide tube 231 is designed to be 40°~50°, more preferably 45°; the number of blades is determined according to the diameter and flow velocity of the secondary swirl separation guide tube 231, usually 12~18 blades per layer, preferably 16 blades; all swirl plate 232 blades rotate in the same direction (e.g., left-handed or right-handed), and opposite to the rotation direction of the swirl-generating guide blade 222. In this invention, the swirl plate 232 blades are preferably right-handed and only a single layer of swirl plates is provided. If it is necessary to enhance the swirl effect, 2~3 layers of swirl plates 232 can be arranged axially at intervals within the secondary swirl separation guide tube 231, with the spacing between each layer being 2~5 times the blade height.

[0041] The design of the swirl plate 232 has the following advantages: (1) High-efficiency cyclone enhancement, secondary cyclone enhancement in the secondary cyclone separation guide tube, blade tilt angle and structural design enable the liquid-solid mixed phase to form a strong rotating vortex in the secondary cyclone separation guide tube 231. Centrifugal force throws the coarse catalyst toward the tube wall of the secondary cyclone separation guide tube 231, forming a clear layered arrangement in the radial direction, which significantly improves the separation efficiency. (2) Optimize the flow field distribution. The uniformly distributed swirl plates 232 ensure that the fluid velocity distribution is uniform on the cross section of the secondary swirl separation guide tube 231, reducing dead zones and eddy losses, and lowering pressure drop; the inward-facing structure resists clogging. (3) The design of the swirl plate 232 with a low middle and a high outer side can reduce the accumulation of particles on the surface of the swirl plate 232 and further prevent clogging.

[0042] The secondary cyclone separator 3 has discharge ports at its top and bottom. The top discharge port discharges the powdered catalyst, while the bottom discharge port is connected to the lower part of the reactor pressure shell 1 via a pipe, enabling the fine catalyst to be separated and reused externally by cyclone separation. In this invention, the secondary cyclone separator 3 is preferably a tangentially fed cyclone separator, and more preferably a cyclone separator with a separation accuracy of 2–50 μm.

[0043] To allow the crude catalyst, after primary and secondary cyclone separation, to flow back from the three-phase cyclone separator 2 into the reactor pressure shell 1 to continue participating in the reaction, such as... Figure 1 and Figure 2As shown, a check cone 6 is provided at the lower end of the underflow pipe 213, and a gap is left between the check cone 6 and the inlet of the underflow pipe 213 for the discharge of large-diameter catalyst particles, liquid phase, and other substances. The check cone 64 is set at the end of the underflow pipe 213 via a connecting bracket. In order to ensure good overall stability of the separator body 21, it is preferable to weld the check cone 6 to the end of the underflow pipe 213 via the bracket. The structure of the check cone 6 is preferably a spindle-shaped structure, and more preferably a spindle-shaped structure with an upper cone angle of 15-150° and a lower cone angle smaller than the upper cone angle. In addition, the check cone 6 can also prevent the three-phase mixture, as well as large-diameter catalyst particles, liquid phase, and other substances discharged from the underflow port at the lower end of the underflow pipe 213, from entering the three-phase separator from the underflow port at the lower end of the underflow pipe 213.

[0044] The catalyst online recycling and reuse device in this suspended bed hydrogenation reactor can separate the crude catalyst through a three-phase cyclone separator 2, allowing the crude catalyst to return to the suspended bed hydrogenation reactor to continue participating in the reaction; a centrifugal force field is applied to the liquid phase crude product through a secondary cyclone separator 3, removing the fine catalyst from the underflow port of the secondary cyclone separator 3 and passing it into the bottom of the reactor pressure shell 1, where it enters the reactor through external circulation to continue participating in the reaction; the liquid phase product containing powdered catalyst obtained after removing the fine catalyst is stored, or the powdered catalyst is processed and the remaining part is sent back to the suspended bed reactor to continue participating in the reaction.

[0045] Because some of the fluid (or entrained dispersed phase particles) entering the three-phase cyclone separator 2 fails to undergo sufficient rotational motion or residence time within the separation chamber to achieve effective separation, it forms a short-circuit flow, escaping directly and rapidly from the liquid phase outlet, thus reducing separation efficiency. Therefore, in order to better achieve secondary cyclone separation of the crude catalyst, reduce the occurrence of short-circuit flow, and improve separation efficiency, such as... Figure 2 As shown, the upper end of the straight section b2211 is lower than the upper end of the straight section a211, and the lower end of the straight section b2211 is higher than the lower end of the straight section a211. The upper end of the secondary cyclone separator guide tube 231 is lower than the upper end of the straight section b2211, and the lower end of the secondary cyclone separator guide tube 231 is lower than the lower end of the straight section b2211. Furthermore, to prevent the liquid phase in the three-phase cyclone separator 2 from flowing back into the annular channel between the primary cyclone separator guide tube 221 and the secondary cyclone separator guide tube 231, the inward bend angle α at the lower end of the straight section b2211 and the outward bend angle α′ at the lower end of the secondary cyclone separator guide tube 231 are both 20° to 40°. The reason why α and α′ are set to 20-40° is that when α and α′ are less than 20°, the anti-backflow effect is not obvious, and when α and α′ are greater than 40°, it will affect the flow of liquid-solid mixed phase in the annular channel. Therefore, in this invention, it is preferred that α and α′ are both 20-40°, and more preferably that α and α′ are both 30°.

[0046] Thus, the inward folding structure at the lower end of the straight section b2211 reduces the cross-sectional area of ​​the lower end of the annular channel between the primary cyclone separator guide tube 221 and the secondary cyclone separator guide tube 231. According to Bernoulli's principle, the flow velocity of the secondary fluid (mainly fine-particle catalyst) passing through this throat will increase, forming a high-intensity turbulent fluid. Since the secondary fluid has good flow properties, it will not cause blockage at the reduced cross-sectional area at the lower end of the annular channel. Under the guidance of the outward folding structure at the lower end of the secondary cyclone separator guide tube 231, the high-speed secondary fluid directly impacts the short-circuit flow, destroying the boundary layer of the guide structure in the form of active guidance, fundamentally and completely eliminating the short-circuit flow, thereby effectively blocking coarse particles from entering the inner cyclone region and greatly improving the separation accuracy.

[0047] It is important to note here that: 1) The upper end of the secondary cyclone separation guide tube 231 is lower than the straight section b2211. This allows some of the liquid crude product near the center of the secondary cyclone separation guide tube 231 to move upward along the secondary cyclone separation guide tube 231 under the action of swirling in the cyclone plate 232, and finally move out of the reactor from the liquid phase outlet end of the outlet pipe 2213. 2) The swirl plate 232 is set at the lower end of the swirl guide vane 222, which can maximize the tangential velocity of the liquid phase coarse product, so that the liquid phase coarse product enters the stratification state where the fine-diameter catalyst particles are thrown to the outside as early as possible, thereby improving the screening efficiency.

[0048] Furthermore, such as Figure 3 As shown, in order to ensure that the three-phase mixture entering the three-phase cyclone separator 2 generates sufficient centrifugal force under the guiding action of the cyclone guide vane 222, and at the same time ensure the drainage volume during the overflow of the annular gap, the inner diameter Da of the straight section b2211 is 60 to 80% of the inner diameter D of the straight section a211. Preferably, the inner diameter Da of the straight section b2211 is 65% of the inner diameter D of the straight section a211.

[0049] Considering that during operation, the gas content and catalyst particle ratio in the lower part of the inner cavity of the straight section a211 are approximately 30-40%, and the liquid phase ratio is approximately 60-70%, during upward fluidization, the gas phase ratio decreases, catalyst particles aggregate, and the liquid phase ratio increases. To prevent the liquid phase from carrying away catalyst particles and escaping while flowing upward at the same speed, the liquid velocity of the secondary cyclone separator guide tube 231 needs to be reduced. Therefore, the inner diameter D0 of the secondary cyclone separator guide tube 231 is limited to 70-90% of the inner diameter Da of the straight section b2211, which is greater than the maximum liquid phase ratio, in order to reduce the actual liquid phase velocity and thus effectively reduce the probability of coarse catalyst being entrained in the liquid phase. Based on the above, it is preferable that the inner diameter D0 of the secondary cyclone separator guide tube 231 is 80% of the inner diameter Da of the straight section b2211, so that the amount of coarse catalyst carried away is less than or equal to 0.01 μg / g.

[0050] Furthermore, combined Figure 2 As shown, the height difference between the axis of the liquid phase outlet and the upper end of the straight section a211 is h1, where h1 is 20-40% of the inner diameter Dn of the reactor pressure shell 1. This reduces the required fluidization velocity within the suspended bed reactor and lowers energy consumption. Preferably, h1 is 30%, 40%, or 50% of the inner diameter Dn of the reactor pressure shell 13, with the optimal value being 30% of the inner diameter Dn of the reactor pressure shell 1. At this value, the required fluidization velocity within the suspended bed reactor is minimized, and energy consumption is lowest.

[0051] Furthermore, combined Figure 2 As shown, the fluidization height of the suspended bed reactor is higher than the upper end of the straight section a211, and the height difference between the two is h2, where h2 is 5-20% of the inner diameter Dn of the reactor pressure shell 1. This reduces the energy required to reach the fluidization height and lowers the pressure inside the three-phase cyclone separator 2. Preferably, h2 is 5%, 10%, or 15% of the inner diameter Dn of the reactor pressure shell 1. The optimal value is 5% of the inner diameter Dn of the reactor pressure shell 1, at which point the energy required to reach the fluidization height is minimized and the pressure drop inside the three-phase separator is minimized.

[0052] Example 2

[0053] This embodiment describes in detail the online recycling and staged reuse of catalyst in the suspended bed hydrogenation reactor as described in Example 1, including the following steps: S1 crude catalyst internal circulation primary cyclone separation and reuse: Specifically, after a portion of the liquid-solid-gas three-phase mixture in the suspended bed hydrogenation reactor is discharged from the gas phase outlet 11 (mainly large bubbles), the remaining portion undergoes primary cyclone separation from top to bottom in the suspended bed hydrogenation reactor through the primary cyclone separation component 22 of the three-phase cyclone separator 2. The separated crude catalyst flows out of the three-phase cyclone separator 2 along the inner wall of the separator body 21 and returns to the suspended bed hydrogenation reactor to continue participating in the reaction. S2 crude catalyst internal circulation two-stage cyclone separation and reuse: Specifically, the liquid-solid mixed phase after primary cyclone separation undergoes secondary cyclone separation from bottom to top through the secondary cyclone separation component 23 of the three-phase cyclone separator 2. The separated gas phase (mainly small bubbles) is discharged through the gas phase outlet 11. The separated crude catalyst is accelerated to rotate by the rotational guiding effect of the cyclone plate 232 and is thrown towards the inner wall of the primary cyclone separation guide tube 221 at the uppermost end of the secondary cyclone separation guide tube 231. It then flows out of the three-phase cyclone separator 2 along the annular channel between the primary cyclone separation guide tube 221 and the secondary cyclone separation guide tube 231 and returns to the suspended bed hydrogenation reactor to continue participating in the reaction. The remaining material in the three-phase cyclone separator 2 is led out of the suspended bed hydrogenation reactor as a liquid crude product through the pipe connecting the three-phase cyclone separator 2 and the secondary cyclone separator 3. The flow direction diagram of the gas-liquid-solid mixed phase in steps S1 and S2 in the three-phase cyclone separator 2 is shown below. Figure 4 As shown, the red arrow indicates the direction of the primary swirl flow of the crude catalyst, the orange arrow indicates the direction of the secondary swirl flow of the crude catalyst, the blue arrow indicates the direction of the gas phase flow, and the green arrow indicates the direction of the liquid phase crude product flow. S3 fine catalyst external circulation cyclone separation and reuse, and powdered catalyst discharge: Specifically, the crude liquid product is separated into fine catalysts by an external secondary hydrocyclone separator 3. The fine catalysts re-enter the suspended bed hydrogenation reactor to continue participating in the reaction. The remaining material in the secondary hydrocyclone separator 3 is discharged as a liquid product from the secondary hydrocyclone separator 3, thereby discharging the powdered catalyst retained in the discharged liquid product.

[0054] Example 3

[0055] This embodiment describes in detail a system for online recycling and staged reuse of catalysts in a suspended bed reactor.

[0056] like Figure 5 and Figure 6 As shown, the system for online recycling and staged reuse of catalyst in a suspended bed reactor includes at least two catalyst online recycling and staged reuse devices connected in series. The liquid crude product of the first-stage catalyst online recycling and staged reuse device is desolidified by a secondary hydrocyclone separator (102, 302), and its top outlet is connected to the gas-liquid-solid mixed-phase inlet of the next-stage catalyst online recycling and staged reuse device through a pipeline. The liquid level height difference h3 between any two adjacent catalyst online recycling and staged reuse devices is greater than the friction loss by 0.3 to 2 m.

[0057] Among them, the friction loss is the sum of the pipeline losses that the fluid loses to overcome the pipeline losses connecting the two-stage catalyst online circulation and recycling device and the mechanical energy lost in raising the liquid level required to raise the next stage catalyst online circulation and recycling device.

[0058] Friction loss Using Darcy's formula, that is: ; In the formula, Indicates the height of the reactor's pressure shell. Indicates the inner diameter of the reactor's pressure shell. This represents the average flow velocity across the fluid cross-section. Represents gravitational acceleration. This represents the friction coefficient.

[0059] The system operates as follows: The gas-liquid-solid three-phase mixture entering the suspended bed hydrogenation reactor (100, 300) moves upwards into the upper space of the reactor (100, 300) under fluidization. After reaching the liquid level of the fluidized bed, large bubbles burst due to inertia and continue to move upwards, eventually exiting from the gas phase outlet. The remaining mixture, being heavier, falls into the annular channel formed by the straight section a211 of the three-phase cyclone separator 2 and the straight section b2211 of the first-stage cyclone separation guide pipe 221. Under the action of the swirl-generating guide vanes 222, this annular channel forms a swirling field. The liquid-solid two-phase mixture undergoes swirling separation under centrifugal force. Due to the large density difference between the liquid and solid phases, the coarse catalyst particles move towards the sidewall of the straight section a211 and downwards along the wall, flowing out from the underflow outlet of the underflow pipe 213 and returning to the reactor to continue the reaction. The liquid-solid mixture converges near the axis of the three-phase cyclone separator 2 and continues to flow upward into the secondary cyclone separator guide tube 231. Under the cyclone acceleration effect of the cyclone plate 232, the tangential velocity of the liquid-solid mixture increases significantly, causing the coarse catalyst present in the liquid-solid mixture to be thrown against the side wall of the secondary cyclone separator guide tube 231. When it moves to the opening at the upper end of the secondary cyclone separator guide tube 231, the coarse catalyst in the outer layer of the liquid-solid mixture loses the support of the side wall of the secondary cyclone separator guide tube 231 and is thrown against the inner wall of the primary cyclone separator guide tube 221 under the action of huge centrifugal force. It then flows downward into the annular channel of the primary cyclone separator guide tube 221 and the secondary cyclone separator guide tube 231. At the outlet of the annular channel, it mixes with the coarse catalyst retained on the lower wall of the primary cyclone separator guide tube 221 and flows downward together out of the three-phase cyclone separator 2, restarting the internal circulation. The crude liquid product remaining in the secondary cyclone separator guide pipe 231 flows upward, enters the outlet pipe 2213, and is removed from the reactor from the liquid phase outlet end. The crude liquid product entering the secondary cyclone separator (102, 302) is separated into fine catalyst under the action of centrifugal force. The fine catalyst is discharged from the bottom outlet and transported back to the reactor pressure shell 1 through the pipeline to continue the reaction. The remaining liquid product is discharged from the top outlet and pressurized by the booster pump (105, 304) before being fed into the secondary series suspended bed hydrogenation reactor (200, 400) to repeat the above separation process.

[0060] This device, method, and system, developed by the inventors after extensive and in-depth research, addresses the problems of short operating cycles, large catalyst consumption, and easy coking and deactivation of catalysts in existing fluidized bed hydrogenation reactors. It achieves this by incorporating a secondary cyclone separator 23 within the primary cyclone separator 22, fully coupling the primary and secondary cyclone separators to achieve internal recycling of the coarse catalyst, reducing the amount of fresh catalyst added and thus reducing catalyst consumption. Simultaneously, a secondary cyclone separator 3 is installed outside the reactor to achieve external recycling of the fine catalyst and remove powdered catalyst from the reactor, controlling the catalyst particle size within a suitable range. Compared to other existing methods, this method offers advantages such as low system operating energy consumption, reduced coking, and long stable operating cycles. Furthermore, the device for online recycling and staged catalyst reuse in a fluidized bed hydrogenation reactor is a highly efficient, low-energy-consumption, and safe biomass energy device.

[0061] Experimental Example 1

[0062] The system from Example 3 was applied to a cold model test of a 4000L / h suspended bed hydrogenation reactor.

[0063] 1) The composition of the experimental equipment and the process flow are as follows:

[0064] like Figure 5 As shown, the online catalyst recycling system in the suspended bed reactor used in this experimental example includes two catalyst online recycling units connected in series, and their connection method is as follows: The outlet of the water pump 205 is connected to the first mixing tank 206 through a pipeline. The first mixing tank 206 and the air compressor 103 are connected together through a pipeline to the gas-liquid-solid mixed phase inlet of the first suspended bed hydrogenation reactor 100. The crude liquid product from the first suspended bed hydrogenation reactor 100 is connected to the first secondary hydrocyclone 102 via the first crude liquid product outlet pipe 101. The top center outlet of the first secondary hydrocyclone 102 is connected to the first booster pump 105 via the first liquid product outlet pipe a104. The first booster pump 105 is then connected to the gas-liquid-solid mixed-phase inlet of the second suspended bed hydrogenation reactor 200 via the first liquid product outlet pipe b106. The underflow outlet of the first secondary hydrocyclone 102 transports the fine catalyst back to the first suspended bed hydrogenation reactor 100 via a pipeline. The crude liquid product from the second suspended bed hydrogenation reactor 200 is connected to the second secondary hydrocyclone 202 via the second crude liquid product outlet pipe 201. The top center outlet of the second secondary hydrocyclone 202 is connected to the inlet of the circulation tank 204 via the second crude liquid product outlet pipe 203. The underflow outlet of the second secondary hydrocyclone 202 transports the fine catalyst back to the second suspended bed hydrogenation reactor 200 via a pipeline. The outlet of the circulating tank 204 is connected to the inlet of the water pump 205 via a pipeline.

[0065] Combination Figure 5 As shown, the process flow of this experiment is as follows: Water, after being pressurized by water pump 205, enters the first mixing tank 206 together with the catalyst for stirring and premixing. Air compressed by air compressor 103 and the liquid-solid mixture flowing out of the first mixing tank 206 are combined through a pipeline and sent into the first suspended bed hydrogenation reactor 100 through the gas-liquid-solid mixed phase inlet at the bottom of the first suspended bed hydrogenation reactor 100. Under the action of air and water, the catalyst particles in the first suspended bed hydrogenation reactor 100 reach a suspended state. The gas-liquid-solid three-phase mixture in the first suspended bed hydrogenation reactor 100 is separated by three-phase cyclone separator 2. The obtained gas phase (and air) is discharged from the gas phase outlet of the first suspended bed hydrogenation reactor 100, and the obtained liquid phase crude product is discharged from the first liquid phase crude product outlet pipe 101 and sent to the first and second stage cyclone separator 102 for separation and desolidification. The obtained fine catalyst is discharged from the underflow port of the first and second stage cyclone separator 102. The catalyst is connected to the bottom of the first suspended bed hydrogenation reactor 100 through a pipeline and returns to the first suspended bed hydrogenation reactor 100 to participate in the reaction. The obtained liquid product enters the first booster pump 105 through the first liquid product outlet pipe a104, and is pressurized by the first booster pump 105 and sent to the second suspended bed hydrogenation reactor 200 in series through the first liquid product outlet pipe b106 for reaction. After entering the second suspended bed hydrogenation reactor 200, the working process of the first suspended bed hydrogenation reactor 100 is repeated, so as to realize the online circulation and staged reuse of the catalyst. The gas phase (and air) obtained in the second suspended bed hydrogenation reactor 200 is discharged from the gas phase outlet of the second suspended bed hydrogenation reactor 200. The obtained crude liquid product enters the second secondary cyclone separator 202 for separation and desolidification through the second crude liquid product outlet pipe 201. The obtained liquid product is sent to the circulation tank 204 for recycling through the second liquid product outlet pipe 203.

[0066] Here, h3 represents the liquid level difference between the first suspended bed hydrogenation reactor 100 and the second suspended bed hydrogenation reactor 200.

[0067] 2) Main structural dimensions of the suspended bed hydrogenation reactor

[0068] The main structural dimensions of the suspended bed hydrogenation reactor are shown in Table 1. The first suspended bed hydrogenation reactor 100 and the second suspended bed hydrogenation reactor 200 have completely identical dimensions and structures; the first secondary cyclone separator 102 and the second secondary cyclone separator 202 have completely identical dimensions and structures.

[0069] Table 1: Structural Dimensions of the Cold Model Device for a 4000L / h Suspended Bed Hydrogenation Reactor

[0070] 3) Experimental Results

[0071] The test process of the cold model device of the 4000L / h suspended bed hydrogenation reactor was carried out using water and air. The test results are shown in Table 2.

[0072] Table 2: Test Results of the Cold Model Device for a 4000 L / h Suspended Bed Hydrogenation Reactor

[0073] Note: The catalyst used is spherical catalyst particles of Mo and Co supported on alumina.

[0074] The experimental results show that the internal flow of the suspended bed hydrogenation reactor (100, 200) reached a fully mixed state, and the catalyst was uniformly fluidized. No malfunctions occurred during 100 hours of continuous operation. The amount of coarse catalyst carried out in the liquid phase crude product was controlled to be less than or equal to 1.6 μg / L, and the amount of fine catalyst carried out in the liquid phase product was controlled to be less than or equal to 1.8 μg / L. The device exhibits good performance in controlling catalyst particle size.

[0075] Experimental Example 2

[0076] The system in Example 3 was applied to a 300,000-ton / year biomass pyrolysis liquid hydrodeoxygenation process.

[0077] 1) The composition of the experimental equipment and the process flow are as follows: like Figure 6 As shown, the online circulation and staged reuse system of catalyst in the suspended bed hydrogenation reactor used in this test example includes two catalyst online circulation and staged reuse devices connected in series. The connection method is as follows: the outlet of the mixing tank 406 is connected to the inlet of the heating furnace 407 through a pipeline. Two identical heating furnaces 407 heat the liquid-solid mixed phase and hydrogen, respectively; the liquid outlet of the heating furnace 407 heating the liquid-solid mixed phase is connected to the gas-liquid-solid mixed phase inlet of the third suspended bed hydrogenation reactor 300 through a pipeline; the gas outlet of the heating furnace 407 heating the hydrogen is connected to the gas-liquid-solid mixed phase inlets of the third suspended bed hydrogenation reactor 300 and the fourth suspended bed hydrogenation reactor 400, respectively, through pipelines. The third liquid phase crude product outlet pipe 301 of the third suspended bed hydrogenation reactor 300 is connected to the side tangential feed port of the third secondary hydrocyclone 302. The top center outlet of the third secondary hydrocyclone 302 is connected to the second booster pump 304 through the third liquid phase product outlet pipe a303. The second booster pump 304 is connected to the gas-liquid-solid mixed phase inlet of the fourth suspended bed hydrogenation reactor 400 through the third liquid phase product outlet pipe b305. The gas phase outlet of the third suspended bed hydrogenation reactor 300 is connected to the air inlet of the separator 404 through the air cooler 405. The fourth liquid phase crude product outlet pipe 401 of the fourth suspended bed hydrogenation reactor 400 is connected to the side tangential feed port of the fourth secondary hydrocyclone 402, and the top center outlet of the fourth secondary hydrocyclone 402 is connected to the liquid inlet of the separator 404 through the fourth liquid phase product outlet pipe 403; the gas phase outlet of the fourth suspended bed hydrogenation reactor 400 is connected to the air inlet of the separator 404 through the air cooler 405.

[0078] Combination Figure 6 As shown, the process flow of this experimental example is as follows: the catalyst and biomass pyrolysis oil are fully premixed in the second mixing tank 406, heated to a certain temperature by the heater 407, and then enter the third suspended bed hydrogenation reactor 300; at the same time, hydrogen is heated by the heater 407 and enters the third suspended bed hydrogenation reactor 300 through the gas-liquid-solid mixed phase inlet at the bottom. Under the action of the gas-liquid-solid distributor, the hydrogen, biomass pyrolysis oil, and catalyst are mixed to reach a fluidized state; in the third suspended bed hydrogenation reactor 300, the gas-liquid-solid three-phase mixture is separated by a three-phase cyclone separator. The obtained hydrogen is discharged from the gas phase outlet, cooled by the air cooler 405, and then sent to the subsequent process for purification. The obtained liquid phase crude product is connected to the third secondary cyclone separator 302 through the third liquid phase crude product outlet pipe 301. The fine catalyst obtained after solidification by cyclone separation is discharged from its underflow outlet and connected to the third suspended bed hydrogenation reactor through a pipeline. The bottom of reactor 300 is connected back to the third suspended bed hydrogenation reactor 300 to participate in the reaction. The obtained liquid product enters the second booster pump 304 through the third liquid product outlet pipe a303. After being pressurized by the second booster pump 304, it is sent to the fourth suspended bed hydrogenation reactor 400 in a two-stage series through the third liquid product outlet pipe b305 for reaction, thus realizing the online circulation and staged reuse of catalyst. The hydrogen obtained from the fourth suspended bed hydrogenation reactor 400 is discharged from the gas phase outlet, cooled by the air cooler 405, and then sent to the subsequent process for purification. The obtained liquid crude product is sent to the fourth secondary cyclone separator 402 through the fourth liquid crude product outlet pipe 401. The fine catalyst obtained after cyclone solidification is discharged from its underflow port and participates in the reaction again through a pipeline connected to the bottom of the fourth suspended bed hydrogenation reactor 400. The obtained liquid product enters the separator 404 for separation.

[0079] Here, h3 represents the liquid level difference between the third suspended bed hydrogenation reactor 300 and the fourth suspended bed hydrogenation reactor 400.

[0080] 2) Main structural dimensions of the suspended bed hydrogenation reactor

[0081] The main structural dimensions of the suspended bed hydrogenation reactor are shown in Table 3 below. The dimensions of the third suspended bed hydrogenation reactor 300 and the fourth suspended bed hydrogenation reactor 400 are completely identical.

[0082] Table 3: Structural Dimensions of a 10-ton / year Residue Oil Hydrodeoxygenation Suspended Bed Hydrogenation Reactor

[0083] 3) Experimental Results

[0084] The test process of the 10-ton / year suspended bed hydrodeoxygenation unit was carried out using biomass pyrolysis oil. The test results are shown in Table 4 below.

[0085] Table 4: Results of Hydrodeoxygenation Test of 300,000 tons / year Biomass Pyrolysis Oil

[0086] Note: The catalyst used is spherical catalyst particles of Mo and Co supported on alumina.

[0087] The test results show that both the third suspended bed hydrogenation reactor 300 and the fourth suspended bed hydrogenation reactor 400 achieved a fully mixed flow state internally, with uniform catalyst fluidization. They operated continuously for 800 hours without any malfunctions, and the catalyst carried out by the liquid phase product contained no coarse catalyst; the amount of fine catalyst carried out was controlled to be less than or equal to 5 ppm; and the proportion of powdered catalyst was greater than or equal to 99%. Furthermore, under different hydrogen-to-oil ratios, the device demonstrated good performance in catalyst particle size sieving.

[0088] Those skilled in the art will recognize that the embodiments and experimental examples described herein are intended to help the reader understand the principles of the invention and should be understood as not limiting the scope of protection of the invention to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. A device for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor, comprising a three-phase cyclone separator (2) disposed within the pressure-bearing shell (1) of the reactor, characterized in that, It also includes a secondary cyclone separator (3) installed outside the reaction pressure shell (1); the three-phase cyclone separator (2) is connected to the secondary cyclone separator (3) through a pipeline; The three-phase cyclone separator (2) includes a separator body (21) coaxially arranged and nested together in sequence, a first-stage cyclone separation component (22) and a second-stage cyclone separation component (23). The primary cyclone separation assembly (22) is used to achieve primary cyclone separation of the crude catalyst in the catalyst; the primary cyclone separation assembly (22) includes a primary cyclone separation guide pipe (221) and two or more cyclone-generating guide vanes (222). The secondary cyclone separation component (23) is used to achieve secondary cyclone separation of the crude catalyst in the catalyst; the secondary cyclone separation component (23) includes a secondary cyclone separation guide pipe (231) and two or more cyclone plates (232). The swirling guide vane (222) is disposed in the annular channel between the separator body (21) and the first-stage swirling separation guide tube (221) and is fixedly connected to both; the swirling plate (232) is disposed circumferentially along the axis of the second-stage swirling separation guide tube (231) at the lower end of the inner wall of the second-stage swirling separation guide tube (231); The secondary cyclone separator (3) is used to separate the fine catalyst in the catalyst and discharge the powdered catalyst; the top and bottom of the secondary cyclone separator (3) are respectively provided with discharge ports; and the bottom discharge port is connected to the lower part of the reactor pressure shell (1) through a pipe.

2. The apparatus for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 1, characterized in that, The reactor pressure shell (1) is provided with a gas phase outlet (11) at the top and a gas-liquid-solid mixed phase inlet (12) at the bottom; the three-phase cyclone separator (2) is located below the gas phase outlet (11) inside the reactor pressure shell (1); a gas-liquid-solid distributor (4) is also provided inside the reactor pressure shell (1) above the gas-liquid-solid mixed phase inlet (12).

3. The apparatus for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 1, characterized in that, The separator body (21) includes a straight cylindrical section a (211), a conical section a (212), and an underflow pipe (213) connected coaxially from top to bottom. The outer wall of the straight cylindrical section a (211) is connected to the inner wall of the reactor pressure shell (1) through two or more first connectors (5). The underflow pipe (213) is provided with a check cone (6) at its lower end.

4. The apparatus for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 3, characterized in that, The first-stage cyclone separator guide pipe (221) includes a straight cylindrical section b (2211), a conical section b (2212), and an outlet pipe (2213) connected coaxially from bottom to top; the inner wall of the straight cylindrical section b (2211) is connected to the outer wall of the second-stage cyclone separator guide pipe (231) through a second connector (7); the outer wall of the straight cylindrical section b (2211) is connected to the inner wall of the straight cylindrical section a (211) through a swirl-generating guide vane (222); the outlet pipe (2213) includes a vertical gas phase outlet end and a horizontal liquid phase outlet end; the liquid phase outlet end is connected to the feed port of the second-stage cyclone separator (3) through a pipe.

5. The apparatus for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 4, characterized in that, The upper end of the straight section b (2211) is lower than the upper end of the straight section a (211), the lower end of the straight section b (2211) is higher than the lower end of the straight section a (211), and the inward fold angle α of the lower end of the straight section b (2211) is 20 to 40°. The upper end of the secondary cyclone separator guide tube (231) is lower than the upper end of the straight section b (2211), the lower end of the secondary cyclone separator guide tube (231) is lower than the lower end of the straight section b (2211), and the outward fold angle α′ of the lower end of the secondary cyclone separator guide tube (231) is 20 to 40°.

6. The apparatus for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 5, characterized in that, The inner diameter Da of the straight section b (2211) is 60-80% of the inner diameter D of the straight section a (211); The inner diameter D0 of the secondary cyclone separator guide tube (231) is 70-90% of the inner diameter Da of the straight section b (2211); The height difference between the axis of the liquid phase outlet of the three-phase cyclone separator (2) and the upper end of the straight section a (211) is h1, where h1 is 20-40% of the inner diameter Dn of the reactor pressure shell (1); The fluidization height of the suspended bed hydrogenation reactor is higher than the upper end of the straight section a (211), and the height difference between the two is h2, where h2 is 5 to 20% of the inner diameter Dn of the reactor pressure shell (1).

7. The device for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 1, characterized in that: The separation accuracy of the secondary cyclone separator (3) is 2~50μm.

8. A method for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor, characterized in that: The apparatus for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to any one of claims 1-7 is carried out according to the following steps: S1 crude catalyst internal circulation primary cyclone separation and reuse: After a portion of the liquid-solid-gas three-phase mixture in the suspended bed hydrogenation reactor is discharged from the gas phase outlet (11) of the suspended bed hydrogenation reactor, the remaining portion undergoes first-stage cyclone separation from top to bottom through the first-stage cyclone separation component (22) of the three-phase cyclone separator (2). The separated crude catalyst flows out of the three-phase cyclone separator (2) along the inner wall of the separator body (21) and returns to the suspended bed hydrogenation reactor to continue participating in the reaction. S2 crude catalyst internal circulation two-stage cyclone separation and reuse: The liquid-solid mixed phase after primary cyclone separation undergoes secondary cyclone separation from bottom to top through the secondary cyclone separation component (23) of the three-phase cyclone separator (2). The separated crude catalyst flows out of the three-phase cyclone separator (2) through the annular channel between the primary cyclone separation guide pipe (221) and the secondary cyclone separation guide pipe (231) and returns to the suspended bed hydrogenation reactor to continue participating in the reaction. The remaining material in the three-phase cyclone separator (2) is led out of the suspended bed hydrogenation reactor as a liquid crude product through the pipe connecting the three-phase cyclone separator (2) and the secondary cyclone separator (3). S3 fine catalyst external circulation cyclone separation and reuse, and powdered catalyst discharge: The crude liquid product is separated into fine catalysts by an external secondary hydrocyclone separator (3). The fine catalysts re-enter the suspended bed hydrogenation reactor to continue participating in the reaction. The remaining material in the secondary hydrocyclone separator (3) is discharged from the secondary hydrocyclone separator (3) as a liquid product, thereby discharging the powdered catalyst retained in the discharged liquid product.

9. The method for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 8, characterized in that: The particle size range of the fresh catalyst introduced into the suspended bed hydrogenation reactor is 10~200μm; the particle size of the coarse catalyst is 70%~100% of the particle size of the fresh catalyst; the particle size of the fine catalyst is 30%~70% of the particle size of the fresh catalyst; and the particle size of the powdered catalyst is less than 30% of the particle size of the fresh catalyst.

10. A system for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor, characterized in that, The device includes at least two catalyst online circulation and classification recycling devices according to any one of claims 1 to 7, which are used in series in a staged manner; after the liquid phase crude product of the first-stage catalyst online circulation and classification recycling device is desolidified by the second-stage cyclone separator (3), its top outlet is connected to the gas-liquid-solid mixed phase inlet (12) of the next-stage catalyst online circulation and classification recycling device through a pipeline.

11. The system for online recycling and staged reuse of catalyst in a suspended bed hydrogenation reactor according to claim 10, characterized in that, The liquid level difference h3 between any two adjacent online circulating stage catalyst recycling units is greater than the friction loss by 0.3 to 2 m.

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