A continuous organic liquid hydrogenation system and method with optimized catalyst arrangement

Abstract

The present invention discloses a continuous organic liquid hydrogenation system and method with an optimized catalyst arrangement, which belongs to the technical field of organic liquid hydrogen storage. It includes a hydrogen feeding device, an organic liquid hydrogen storage medium feeding device, a mixer, a heater, a gas-liquid distributor, a reaction device, a product separation device and a hydrogen recycling device. The reaction device includes two reactors in parallel, namely, a trickle bed reaction tower 1 and a trickle bed reaction tower 2. The inside of the two trickle bed reaction towers is divided into multiple catalyst beds according to the height, wherein each bed is filled with catalysts of different mass ratios. The present invention adopts a reactor bed design with an optimized catalyst arrangement, so that the heat release of the reactants at different positions of the reactor is basically consistent, reducing the difficulty of thermal management, and can directly use a one-stage jacketed oil bath to stabilize the reaction temperature. The hydrogen recycling design improves the hydrogen utilization efficiency, reduces the environmental pollution problem of waste gas emissions, and saves production costs.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic liquid hydrogen storage, and in particular relates to a continuous organic liquid hydrogenation system and method with optimized catalyst arrangement. Background Art

[0002] Hydrogen energy is a new energy source with bright prospects. With its advantages of high energy density and cleanliness, it will replace existing energy storage technologies such as lithium-ion batteries.

[0003] The large-scale utilization of hydrogen energy faces numerous challenges, and the main current hydrogen storage methods all have various shortcomings. High-pressure gaseous hydrogen storage is widely used and low-cost, but the high-pressure environment required for charging and discharging hydrogen limits its further development and poses safety risks. Metal hydride hydrogen storage is safe, stable, and has low pressures, but the metal hydride itself is heavy, and the charging and discharging process is limited by its heat and mass transfer capacity, making it unsuitable for use in the mobile transportation sector. Cryogenic liquid hydrogen storage has a high energy density and is a hot technology in the aerospace field, but it is costly, complex, and difficult to store hydrogen for long periods of time.

[0004] Organic liquid hydrogen storage technology boasts high energy density. Safe, stable, and convenient large-scale, long-distance transportation are key priorities for future hydrogen energy development. The hydrogen absorption process of organic liquid hydrogen storage materials, such as ethylcarbazole, is complex, consisting of several distinct elementary reactions. The reaction rates and heat release levels vary at different stages. If continuous hydrogenation is performed using a gas-liquid-solid three-phase trickle bed reactor, the varying heat release in various parts of the reaction bed necessitates multi-stage temperature control, significantly increasing the complexity of equipment design and system control, leading to increased costs. Summary of the Invention

[0005] One of the objectives of the present invention is to provide a continuous organic liquid hydrogenation system with an optimized catalyst arrangement, which directly utilizes a one-stage jacketed oil bath to stabilize the reaction temperature, greatly simplifying the system complexity, reducing the difficulty of system control, and saving costs by adopting a hydrogen recirculation design.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A continuous organic liquid hydrogenation system with optimized catalyst arrangement, comprising a hydrogen feeding device, an organic liquid hydrogen storage medium feeding device, a mixer, a heater, a gas-liquid distributor, a purge device, a reaction device, a product separation device, and a hydrogen recycling device;

[0008] The hydrogen feeding device and the organic liquid hydrogen storage medium feeding device are respectively connected to the inlet of the mixer, hydrogen is provided through the hydrogen feeding device, and the organic liquid hydrogen storage medium is provided through the organic liquid hydrogen storage medium feeding device. After the hydrogen and the organic liquid hydrogen storage medium are mixed in the mixer, they enter the heater connected to the mixer, and the other end of the heater is connected to the reaction device through the gas-liquid distributor;

[0009] The reaction device includes two reactors connected in parallel, namely a trickle bed reaction tower 1 and a trickle bed reaction tower 2. The trickle bed reaction tower 1 and the trickle bed reaction tower 2 are of the same size and shape. The interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into 2 to 4 catalyst beds according to the height, wherein each bed is filled with an inert material and catalysts of different mass ratios, and the catalyst bed located in the lower section is filled with more catalyst than the catalyst bed located in the upper section; each catalyst bed is connected to a temperature sensor to control its temperature, and the reaction temperature of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is controlled by a jacket thermostat.

[0010] The product separation device is connected to the outlets of the trickle bed reaction tower 1 and the trickle bed reaction tower 2, and is used to separate the reactants produced in the reaction device. The liquid phase is collected by the product separation device, and the gas phase passes through the hydrogen recycling device and enters the hydrogen feeding device to be mixed with new hydrogen as a reaction raw material.

[0011] As a preferred embodiment of the present invention, when the interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into two catalyst beds, the mass percentages of the catalyst are 35% to 40% and 60% to 65% from top to bottom; when the interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into three catalyst beds, the mass percentages of the catalyst are 30% to 35%, 40% to 50% and 65% to 75% from top to bottom; when the interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into four catalyst beds, the mass percentages of the catalyst are 30% to 35%, 40% to 50%, 50% to 60% and 65% to 80% from top to bottom.

[0012] As another preferred embodiment of the present invention, baffles with pore sizes slightly smaller than the catalyst particles are arranged between adjacent catalyst beds. The baffles are used to prevent the catalyst particles from being dispersed by the impact of materials in the axial direction of the catalyst bed.

[0013] Further preferably, the top and bottom of the above-mentioned trickle bed reaction tower one and trickle bed reaction tower two are respectively provided with an inlet flange and an outlet flange, the reaction material enters the trickle bed reaction tower through the above-mentioned respective inlet flanges, and the reactant enters the above-mentioned product separation device through the above-mentioned outlet flange, and an atomizing nozzle is provided below the above-mentioned inlet flange, and the reaction material is sprayed onto the catalyst bed through the above-mentioned atomizing nozzle; the reaction temperature of the above-mentioned trickle bed reaction tower one and trickle bed reaction tower two is controlled to 200°C by the jacket.

[0014] It is further preferred that the above-mentioned trickle bed reaction tower 1 and trickle bed reaction tower 2 are heated by the above-mentioned heater, and the above-mentioned gas-liquid distributor is provided with a pressure sensor, the above-mentioned pressure sensor is used to adjust the reactant pressure, and the above-mentioned gas-liquid distributor is used to control the reactant flow rate, so that the reactant stagnation time inside the reactor is maintained in a reasonable range, thereby protecting the thermal management effect of the optimized catalyst arrangement.

[0015] It is further preferred that the above-mentioned hydrogen feeding device mainly includes a hydrogen cylinder, a low-pressure buffer tank and a high-pressure buffer tank. The above-mentioned hydrogen cylinder is connected to the above-mentioned low-pressure buffer tank, and hydrogen is provided to the low-pressure buffer tank through the above-mentioned hydrogen cylinder. The above-mentioned low-pressure buffer tank is connected to the above-mentioned high-pressure buffer tank. There are three pipelines in parallel between the low-pressure buffer tank and the high-pressure buffer tank, namely a purge pipeline, a pressure-stabilizing pipeline and a boosting pipeline. The hydrogen after passing through the high-pressure buffer tank is passed into the above-mentioned mixer.

[0016] Further preferably, the above-mentioned organic liquid hydrogen storage medium feeding device mainly includes a raw material tank, which has its own heating and stirring functions. The organic liquid hydrogen storage medium therein is melted into a liquid phase by external heating of the raw material tank, and the above-mentioned raw material tank passes the organic liquid hydrogen storage medium into the above-mentioned mixer through a pipeline connected thereto; the above-mentioned organic liquid hydrogen storage medium is ethylcarbazole or a carbazole-type organic hydrogen storage material added with ethylcarbazole.

[0017] More preferably, the purge device is used to introduce nitrogen, helium, neon, argon, krypton or xenon into the hydrogen feeding device and the organic liquid hydrogen storage medium feeding device for purge.

[0018] It is further preferred that the above-mentioned product separation device mainly includes a high-precipitation tank, in which the gas-liquid separation of the reactants is realized, the collected liquid phase is the reaction product, and the collected gas phase is hydrogen. The above-mentioned hydrogen is mixed with new hydrogen through the above-mentioned hydrogen recycling device as a reaction raw material.

[0019] Another object of the present invention is to provide a continuous organic liquid hydrogenation method with optimized catalyst arrangement, which comprises the following steps in sequence:

[0020] S1, introducing nitrogen into the relevant pipelines of the hydrogen feeding device and the organic liquid hydrogen storage medium feeding device through the purge device for purging;

[0021] S2, preheating and melting the raw materials in the organic liquid hydrogen storage medium feeding device and stirring them, then passing the liquid raw materials into the mixer, and passing hydrogen into the mixer through the hydrogen feeding device; the volume ratio of hydrogen to liquid raw materials is 1000-1500:1;

[0022] S3. Set the heating temperature of the heater to 150°C and the temperature of the two reactors to 200°C respectively. Pass the mixed raw materials obtained in the mixer into one of the reactors through the gas-liquid distributor. When the reactant stagnation time is greater than the set threshold of 120 minutes, the reactant is only passed into this reactor. When the reactant flow rate is too large, resulting in a stagnation time less than the set threshold, part of the excess flow is passed into the other reactor.

[0023] S4. The reactants are passed into a product separation device for gas-liquid separation. The liquid phase obtained by separation is the reaction product, mainly dodecahydroethylcarbazole; the gas phase is unreacted hydrogen, which is passed into a hydrogen recycling device and mixed with new hydrogen as a reaction raw material.

[0024] The present invention provides a continuous organic liquid hydrogenation system with an optimized catalyst arrangement. Its main innovation lies in the parallel design of two reactors. By dividing the two reactors into multiple sections according to height, preferably 2-4 sections in the present invention, and filling different amounts of catalyst in the catalyst bed of each section, the hydrogenation reaction process can be controlled, so that the reaction heat release in the beds at different heights of the reactor is similar, reducing the temperature control requirements of the reactor, that is, reducing the control difficulty caused by the need for multi-section temperature control in the reactor in the prior art. Since the heat release of the catalyst beds at different heights in the present invention is similar, its temperature is easy to control.

[0025] When the flow rate of the reaction device is too large, the residence time of the raw materials is shortened, and the reaction progress is slower than the reaction degree set when the catalyst is arranged, resulting in the catalyst bed being unable to provide a good thermal balance effect; the same is true when the flow rate is small, but when the flow rate is small, the heat release is weaker, and the reaction degree is ahead of the set reaction degree, resulting in insufficient reaction power and weaker heat release, so the requirements for thermal management are also smaller.

[0026] The reaction device of the present invention is provided with two identical reactors connected in parallel. When the total flow rate changes, the flow rate of the reactants is controlled by a gas-liquid distributor so that the stagnation time of the reactants inside the reactors is kept within a reasonable range, thereby protecting the thermal management effect of the optimized arrangement of the catalyst.

[0027] In addition, the present invention also utilizes unreacted hydrogen through a hydrogen recycling device, and uses it together with new hydrogen as raw material gas to participate in the reaction, thereby saving raw materials to a certain extent.

[0028] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0029] (1) The present invention adopts a reactor bed design with optimized catalyst arrangement, which makes the heat release of the reactants at different positions in the reactor basically consistent, reducing the difficulty of thermal management. A one-stage jacketed oil bath can be directly used to stabilize the reaction temperature, greatly simplifying the equipment complexity and reducing the difficulty of system control.

[0030] (2) The present invention adopts a parallel reactor design to maintain the stagnation time of the reactants inside the reactors to be no less than a predetermined threshold, thereby avoiding the problem of mismatch between the reaction process and the catalyst arrangement level caused by the reduction of the reactant stagnation time;

[0031] (3) The present invention adopts a hydrogen recycling design, which improves the hydrogen utilization efficiency, reduces the environmental pollution problem caused by waste gas emissions, and saves production costs.

[0032] In summary, compared with the prior art, the present invention is easy to control the reaction temperature and saves production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below with reference to the accompanying drawings:

[0034] Figure 1 This is a schematic diagram of the general structure of a continuous organic liquid hydrogenation system with optimized catalyst arrangement according to the present invention;

[0035] Figure 2 Schematic diagram of the structure of the reactor of the present invention, mainly showing the structure of a trickle bed reaction tower;

[0036] In the picture:

[0037] 1. Low-pressure buffer tank, 2. High-pressure buffer tank, 3. Pressure reducing valve 1, 4. Ball valve 1, 5. Ball valve 2, 6. Back pressure valve, 7. Ball valve 3, 8. Ball valve 4, 9. Filter 1, 10. Electric booster pump, 11. Check valve 1, 12. Ball valve 5, 13. Filter 2, 14. Pressure reducing valve 2, 15. Gas mass flow meter, 16. Check valve 2, 17. Mixer, 18. Raw material tank, 19. Ball valve 6, 20. Filter 3, 21. Feed pump, 22. Pressure sensor 1, 23. Check valve 3, 24. Safety valve 1, 25. Pressure reducing valve 3, 26. Ball valve 7, 27. Filter 4, 28. Check valve 4, 2 9. Ball valve eight, 30. Ball valve nine, 31. Heater, 32. Gas-liquid distributor, 33. Trickle bed reaction tower one, 34. Trickle bed reaction tower two, 35. High-resolution tank, 36. Filter five, 37. Pressure reducing valve four, 38. Ball valve ten, 39. Ball valve eleven, 40. Needle valve, 41. Safety valve two, 42. Pressure reducing valve five, 43. Drying tank, 44. Check valve five, 45. Pressure sensor two, 46. Ball valve twelve, 47. Ball valve thirteen, 48. Ball valve fourteen, 49. Ball valve fifteen, 50. Inlet flange, 51. Atomizing nozzle, 52. Jacket, 53. Baffle, 54. Catalyst bed, 55. Outlet flange. DETAILED DESCRIPTION

[0038] The present invention provides a continuous organic liquid hydrogenation system and method with optimized catalyst arrangement. To make the advantages and technical solutions of the present invention clearer and more specific, the present invention is described in detail below with reference to specific embodiments.

[0039] Unless expressly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “comprising” and the like will be understood to include stated elements or components but not to exclude other elements or components.

[0040] Throughout this document, for ease of description, spatially relative terms such as "below," "beneath," "below," "above," "above," etc. may be used to describe the relationship of one component or feature to another component or feature in the accompanying drawings. It should be understood that the spatially relative terms are intended to encompass different orientations of the object in use or operation in addition to the orientation depicted in the drawings. For example, if the object in the drawings is turned over, the component described as being "below" or "below" other components or features will be oriented "above" the component or feature. Therefore, the exemplary term "below" can include both below and above. Components may also have other orientations (rotated 90 degrees or other orientations) and the spatially relative terms used herein should be interpreted accordingly.

[0041] The organic liquid hydrogen storage medium mentioned in the present invention refers to ethylcarbazole or a carbazole-based organic hydrogen storage material added with ethylcarbazole.

[0042] The structures and working principles of the "mixer", "gas-liquid distributor" and "heater" mentioned in the present invention can be realized by referring to the existing technology in this field.

[0043] like Figure 1 As shown, the present invention provides a continuous organic liquid hydrogenation system with optimized catalyst arrangement, comprising a hydrogen feeding device, an organic liquid hydrogen storage medium feeding device, a mixer, a heater, a gas-liquid distributor, a purge device, a reaction device, a product separation device and a hydrogen recycling device.

[0044] The above-mentioned hydrogen feeding device and organic liquid hydrogen storage medium feeding device are respectively connected to the inlet of the mixer. The hydrogen feeding device provides raw hydrogen into the mixer, and the organic liquid hydrogen storage medium feeding device provides organic liquid hydrogen storage medium into the mixer. After the raw hydrogen and the organic liquid hydrogen storage medium are mixed in the mixer, they enter the heater connected to the mixer. The other end of the heater is connected to the reaction device through a gas-liquid distributor.

[0045] Specifically, the above-mentioned hydrogen feeding device includes a hydrogen cylinder, a low-pressure buffer tank 1 and a high-pressure buffer tank 2. The hydrogen cylinder is connected to the above-mentioned low-pressure buffer tank. A pressure reducing valve 3 and a ball valve 4 are sequentially arranged on the pipeline connecting the two. The low-pressure buffer tank is connected to the high-pressure buffer tank. There are three pipelines in parallel between the low-pressure buffer tank and the high-pressure buffer tank, namely a purge pipeline, a pressure stabilizing pipeline and a pressurizing pipeline. The hydrogen after the high-pressure buffer tank is introduced into the above-mentioned mixer. A ball valve 12 46 is provided on the purge pipeline, and a ball valve 2 5, a back pressure valve 6, a ball valve 10 are sequentially provided on the pressure stabilizing pipeline. 3 7, a ball valve 4 8, a filter 1 9, an electric booster pump 10 and a one-way valve 11 are sequentially arranged in the boosting pipeline; a ball valve 5 12, a filter 2 13, a pressure reducing valve 2 14, a gas mass flowmeter 15, and a one-way valve 2 16 are sequentially arranged between the high-pressure buffer tank 2 and the mixer 17; each buffer tank is connected to a safety valve and is provided with a pressure sensor; a pressure sensor is provided before and after the pressure reducing valve, and a ball valve 13 47 and a ball valve 14 48 are provided before and after the gas mass flowmeter 15, respectively; a ball valve 15 49 is connected to the line parallel to the gas mass flowmeter 15.

[0046] Specifically, the above-mentioned organic liquid hydrogen storage medium feeding device mainly includes a raw material tank 18, which has its own heating and stirring functions. For example, a stirring device is connected to the top of the raw material tank, and the stirring paddle of the stirring device extends into the raw material tank 18. The heating function adopts an external heating method to heat the outer wall of the raw material tank to make it reach a certain temperature.

[0047] The organic liquid hydrogen storage medium in the raw material tank is melted into a liquid phase by external heating. The raw material tank passes the organic liquid hydrogen storage medium into the mixer through the pipeline connected to it. The pipeline connecting the raw material tank 18 and the mixer is connected in sequence with a ball valve 6 19, a filter 3 20, a feed pump 21, a pressure sensor 1 22, and a one-way valve 3 23. A safety valve 1 24 is arranged between the feed pump 21 and the pressure sensor 1 22, and the safety valve 1 is connected to the raw material tank; the purge pipeline is connected to the liquid feed pipeline of the organic liquid hydrogen storage medium feeding device between the ball valve 6 and the filter 3, and the feed pump 21 can realize liquid flow control.

[0048] The purge device is used to introduce nitrogen or other inert gases, such as helium, neon, argon, krypton, or xenon, into the hydrogen feed device and the organic liquid hydrogen storage medium feed device. Nitrogen is preferred in this invention. The purge line passes sequentially through pressure reducing valve 3 25 , ball valve 7 26 , filter 4 27 , and check valve 4 28 ; the purge line ultimately connects to the gas feed line and liquid feed line through ball valve 8 29 and ball valve 9 30 , respectively.

[0049] Hydrogen and organic hydrogen storage materials are mixed in a mixer, passed through a heater 31 and a gas-liquid distributor 32 and enter two parallel trickle bed reaction towers 1 33 and 2 34 , and after the reaction is completed in the reactor, the hydrogen is collected and passed into a product separation device.

[0050] As the main innovation of the present invention, the design of the reaction device consists of two parallel trickle bed reaction towers 33 and 34. The trickle bed reaction towers 1 and 2 are of the same size and shape. The interiors of the trickle bed reaction towers 1 and 2 are divided into 2 to 4 catalyst beds according to their height, wherein each bed is filled with an inert material and catalysts of different mass ratios, and the catalyst bed located in the lower section is filled with more catalyst than the catalyst bed 54 located in the upper section; each catalyst bed 54 is connected to a temperature sensor to control its temperature, and the reaction temperature of the exterior of the trickle bed reaction towers 1 and 2 is controlled by a jacket constant temperature;

[0051] The above-mentioned heater is equipped with a temperature sensor to control the reaction temperature at 130-150 degrees Celsius; the gas-liquid distributor is equipped with a pressure sensor to control the upstream compressor and feed pump through the control system to adjust the reactant pressure.

[0052] like Figure 2As shown, a jacket 52 is provided outside the reactor for constant temperature control. Four sets of temperature sensors are arranged from top to bottom in the reactor to maintain the temperature at 200 degrees Celsius. The reactor is filled with a mixture of inert material and catalyst. The reactor is divided into multiple sections according to height, and filled with catalysts in different proportions to control the hydrogenation reaction process. This ensures that the reaction heat release in the beds at different heights is similar, reducing the reactor's temperature control requirements. The multi-section layout can be divided into two-section, three-section, and four-section types. In the two-section distribution, the mass percentages of the catalyst are, from top to bottom, 35% to 40% and 60% to 65%; in the three-section distribution, the mass percentages of the catalyst are, from top to bottom, 30% to 35%, 40% to 50%, and 65% to 75%; in the four-section distribution, the mass percentages of the catalyst are, from top to bottom, 30% to 35%, 40% to 50%, 50% to 60%, and 65% to 80%.

[0053] The two trickle bed reaction towers are structured with inlet flanges 50 and outlet flanges 55 at their tops and bottoms. Reactants enter the trickle bed reaction towers through the respective inlet flanges and enter the product separation device through the outlet flanges. Atomizing nozzles 51 are located below the inlet flanges, spraying the reactants onto the catalyst beds for reaction. The reaction temperature of the first and second trickle bed reaction towers is controlled at 200°C via jackets. Baffles 53, with apertures slightly smaller than the catalyst particles, are placed between the catalyst beds to prevent axial dispersion of the catalyst particles due to impact from the material. After the reaction is complete, the reactants enter the product separation device through outlet flanges 55. A temperature control system ensures a constant catalyst bed temperature during the reaction.

[0054] When the flow rate of the reaction device is too large, the residence time of the raw materials is shortened, and the reaction progress is slower than the reaction degree set when the catalyst is arranged, resulting in the catalyst bed being unable to provide a good thermal balance effect; the same is true when the flow rate is small, but when the flow rate is small, the heat release is weaker, and the reaction degree is ahead of the set reaction degree, resulting in insufficient reaction power and weaker heat release, so the requirements for thermal management are also smaller.

[0055] The reaction device consists of two identical reactors connected in parallel. When the total flow rate changes, the reactant flow rate is controlled by a gas-liquid distributor so that the reactant stagnation time inside the reactor remains within a reasonable range, protecting the thermal management effect of the optimized catalyst layout.

[0056] The product separation device is connected to the outlet of the trickle bed reaction tower 1 and the trickle bed reaction tower 2, and is used to separate the reactants produced in the reaction device. The liquid phase is collected by the product separation device, and the gas phase enters the hydrogen feeding device through the hydrogen recycling device and is mixed with new hydrogen as a reaction raw material.

[0057] Specifically, the above-mentioned product separation device includes a high-purity tank 35, the liquid phase is discharged from the bottom of the high-purity tank 35, and a ball valve 11 39 and a needle valve 40 are provided on the pipeline connected thereto. The gas phase is discharged from the upper part of the high-purity tank 35, and a filter 5 36, a pressure reducing valve 4 37, and a ball valve 10 38 are provided on the pipeline connected thereto. The high-purity tank is provided with temperature, pressure and flow sensors, and the high-purity tank is connected to a safety valve 2 41; gas-liquid separation is realized in the high-purity tank, and the separated liquid is the reaction product.

[0058] The above-mentioned hydrogen recirculation device includes a hydrogen recirculation pipeline, which passes through a pressure reducing valve 5 42, a drying tank 43, and a one-way valve 5 44 in sequence. A pressure sensor 2 45 is provided between the pressure reducing valve 5 42 and the drying tank 43.

[0059] The following is a detailed description of a continuous organic liquid hydrogenation method with an optimized catalyst arrangement according to the present invention. The method adopts the above-mentioned continuous organic liquid hydrogenation system with an optimized catalyst arrangement. The specific method is as follows:

[0060] (1) Close ball valve 1 (4) and ball valve 6 (19), open ball valve 7 (26) of the purge pipeline, and pass nitrogen to purge the gas feed pipeline and liquid feed pipeline for 10 minutes; during the purge process, close ball valve 2 (5) and ball valve 3 (7) upstream and downstream of back pressure valve 6, close ball valve 4 (8) upstream of electric booster pump 10, and open parallel ball valve 12 (46); close ball valve 13 (47) and ball valve 14 (48) upstream and downstream of the gas flow meter, and open parallel ball valve 15 (49).

[0061] (2) adding ethylcarbazole, an organic hydrogen storage material, to the raw material tank of the liquid feed pipeline, preheating to 80 degrees Celsius and stirring after melting;

[0062] (3) Close the purge pipeline ball valve seven 26, ball valve eight 29, and ball valve nine 30, open the material inlet ball valve one 4 and ball valve six 19, and operate the back pressure valve and the gas mass flow meter upstream and downstream and the parallel ball valve in the opposite manner to (1). Introduce high-purity hydrogen into the gas feed pipeline, with a volume ratio of hydrogen to ethylcarbazole of 1000:1;

[0063] (3) Set the heater temperature to 150 degrees Celsius and the reactor temperature to 200 degrees Celsius;

[0064] (4) The reactants are first introduced into the trickle bed reaction tower 1 33. When the stagnation time of the reactants in the trickle bed reaction tower 1 33 is greater than the set threshold value of 120 min (when the air velocity is about 0.5), the reactants are only introduced into the trickle bed reaction tower 1 33. When the reactant flow rate is too large and the stagnation time is less than the set threshold value, part of the overload flow rate is introduced into the trickle bed reaction tower 2 34.

[0065] (5) The material is passed from the reactor into the high pressure separation tank 35, where gas-liquid separation is performed. The liquid phase obtained by separation is the reaction product, mainly dodecahydroethylcarbazole; the gas phase is unreacted hydrogen, which is passed into the hydrogen recirculation pipeline and returned to the low-pressure buffer tank 1 to be mixed with new hydrogen as the reaction raw material.

[0066] The present invention is described in detail below with reference to specific embodiments.

[0067] Example 1:

[0068] The reactor was filled with 1600ml of Ru / Al2O3 catalyst, the inert material was Al2O3, and ethylcarbazole was selected as the organic hydrogen storage material. The diameter of the trickle bed reactor was 32mm, the catalyst arrangement height was 1m, and the catalyst bed was divided into five equidistant sections, with the mass percentages from top to bottom being 30%, 35%, 45%, 60% and 80%. The reactor jacket was temperature-controlled with an oil bath at approximately 200°C. The liquid phase flow rate was 6mL / min, the gas phase flow rate was 6000mL / min, and the reaction space velocity was 0.4h -1 , reaction pressure 7MPa.

[0069] This embodiment can ensure that 94.6% of ethylcarbazole is converted into dodecahydroethylcarbazole.

[0070] Example 2:

[0071] The reactor was filled with 800 mL of Ru / rGO catalyst, SiO3 was selected as the inert material, and a mixture of ethylcarbazole and carbazole in a molar ratio of 1:1 was selected as the organic hydrogen storage material. The diameter of the trickle bed reactor was 23 mm, the catalyst arrangement height was 1 m, and the catalyst bed was divided into five sections with mass percentages of 35%, 40%, 50%, 60% and 75% from top to bottom. The reactor jacket was temperature-controlled with an oil bath at approximately 200°C. The liquid phase flow rate was 3 mL / min, the gas phase flow rate was 4000 mL / min, and the reaction space velocity was 0.5 h -1 , reaction pressure 7MPa.

[0072] This embodiment can ensure that 95.2% of ethylcarbazole and carbazole react to form dodecahydroethylcarbazole and dodecahydrocarbazole.

[0073] The preferred embodiments of the present invention are described in detail above with reference to the accompanying drawings; however, the present invention is not limited thereto.

[0074] Although terms such as low-pressure buffer tank, high-pressure buffer tank, pressure reducing valve 1, ball valve 1, electric booster pump, etc. are used more frequently in this article, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitations is contrary to the spirit of the present invention.

[0075] It should be further noted that the specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A continuous organic liquid hydrogenation method with optimized catalyst arrangement, wherein the continuous organic liquid hydrogenation system comprises a hydrogen feed device, an organic liquid hydrogen storage medium feed device, a mixer, a heater, a gas-liquid distributor, a purge device, a reaction device, a product separation device, and a hydrogen recirculation device; characterized in that: The hydrogen feeding device and the organic liquid hydrogen storage medium feeding device are respectively connected to the inlet of the mixer, hydrogen is provided through the hydrogen feeding device, and the organic liquid hydrogen storage medium is provided through the organic liquid hydrogen storage medium feeding device. After the hydrogen and the organic liquid hydrogen storage medium are mixed in the mixer, they enter the heater connected to the mixer, and the other end of the heater is connected to the reaction device through the gas-liquid distributor; The reaction device includes two reactors connected in parallel, namely a trickle bed reaction tower 1 and a trickle bed reaction tower 2. The trickle bed reaction tower 1 and the trickle bed reaction tower 2 are of the same size and shape. The interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into 2 to 4 catalyst beds according to the height, wherein each bed is filled with an inert material and catalysts of different mass ratios, and the catalyst bed located in the lower section is filled with more catalyst than the catalyst bed located in the upper section; each catalyst bed is connected to a temperature sensor to control its temperature, and the reaction temperature of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is controlled by a jacket thermostat. The product separation device is connected to the outlets of the first trickle bed reaction tower and the second trickle bed reaction tower, and is used to separate the reactants produced in the reaction device. The liquid phase is collected by the product separation device, and the gas phase passes through the hydrogen recycling device and enters the hydrogen feeding device to be mixed with new hydrogen as a reaction raw material. The top and bottom of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 are respectively provided with an inlet flange and an outlet flange. The reaction materials enter the trickle bed reaction tower through their respective inlet flanges, and the reactants enter the product separation device through the outlet flanges. An atomizing nozzle is provided below the inlet flange, and the reaction materials are sprayed onto the catalyst bed through the atomizing nozzle; the reaction temperature of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is controlled to 200° C. by the jacket; the trickle bed reaction tower 1 and the trickle bed reaction tower 2 are heated by the heater, and the gas-liquid distributor is provided with a pressure sensor, which is used to adjust the reactant pressure. The gas-liquid distributor is used to control the reactant flow rate, so that the reactant residence time inside the reactor is kept within a reasonable range, protecting the thermal management effect of the optimized catalyst arrangement; The continuous organic liquid hydrogenation method comprises the following steps: S1, introducing nitrogen into the relevant pipelines of the hydrogen feeding device and the organic liquid hydrogen storage medium feeding device through the purge device for purging; S2, preheating and melting the raw materials in the organic liquid hydrogen storage medium feeding device and stirring them, then passing the liquid raw materials into the mixer, and passing hydrogen into the mixer through the hydrogen feeding device; the volume ratio of hydrogen to liquid raw materials is 1000-1500:1; S3. Set the heating temperature of the heater to 150°C and the temperature of the two reactors to 200°C respectively. Pass the mixed raw materials obtained in the mixer into one of the reactors through the gas-liquid distributor. When the reactant stagnation time is greater than the set threshold of 120 minutes, the reactant is only passed into this reactor. When the reactant flow rate is too large, resulting in a stagnation time less than the set threshold, part of the excess flow is passed into the other reactor. S4. The reactants are passed into a product separation device for gas-liquid separation. The liquid phase obtained by separation is the reaction product, mainly dodecahydroethylcarbazole; the gas phase is unreacted hydrogen, which is passed into a hydrogen recycling device and mixed with new hydrogen as a reaction raw material.

2. The continuous organic liquid hydrogenation method with optimized catalyst arrangement according to claim 1, characterized in that: When the interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into two catalyst beds, the mass percentages of the catalyst are 35%-40% and 60%-65% from top to bottom; when the interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into three catalyst beds, the mass percentages of the catalyst are 30%-35%, 40%-50% and 65%-75% from top to bottom; when the interior of the trickle bed reaction tower 1 and the trickle bed reaction tower 2 is divided into four catalyst beds, the mass percentages of the catalyst are 30%-35%, 40%-50%, 50%-60% and 65%-80% from top to bottom.

3. The continuous organic liquid hydrogenation method with optimized catalyst arrangement according to claim 1, characterized in that: Baffles with pore sizes slightly smaller than those of the catalyst particles are arranged between adjacent catalyst beds. The baffles are used to prevent the catalyst particles from being impacted and dispersed by materials in the axial direction of the catalyst bed.

4. A continuous organic liquid hydrogenation method with optimized catalyst arrangement according to any one of claims 1 to 3, characterized in that: The hydrogen feeding device mainly includes a hydrogen cylinder, a low-pressure buffer tank and a high-pressure buffer tank. The hydrogen cylinder is connected to the low-pressure buffer tank, and hydrogen is provided to the low-pressure buffer tank through the hydrogen cylinder. The low-pressure buffer tank is connected to the high-pressure buffer tank. There are three pipelines in parallel between the low-pressure buffer tank and the high-pressure buffer tank, namely a purge pipeline, a pressure-stabilizing pipeline and a boosting pipeline. The hydrogen after passing through the high-pressure buffer tank is introduced into the mixer.

5. The continuous organic liquid hydrogenation method with optimized catalyst arrangement according to any one of claims 1 to 3, characterized in that: The organic liquid hydrogen storage medium feeding device mainly includes a raw material tank, which has its own heating and stirring functions. The organic liquid hydrogen storage medium in the raw material tank is melted into a liquid phase by external heating. The raw material tank passes the organic liquid hydrogen storage medium into the mixer through a pipeline connected to it; the organic liquid hydrogen storage medium is ethylcarbazole or a carbazole-based organic hydrogen storage material added with ethylcarbazole.

6. A continuous organic liquid hydrogenation method with optimized catalyst arrangement according to any one of claims 1 to 3, characterized in that: The purging device is used to introduce nitrogen, helium, neon, argon, krypton or xenon into the hydrogen feeding device and the organic liquid hydrogen storage medium feeding device for purging.

7. The continuous organic liquid hydrogenation method with optimized catalyst arrangement according to any one of claims 1 to 3, characterized in that: The product separation device mainly includes a high-purity tank, in which the gas-liquid separation of the reactants is realized. The collected liquid phase is the reaction product, and the collected gas phase is hydrogen. The hydrogen is mixed with new hydrogen through the hydrogen recycling device as a reaction raw material.

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