Hydroprocessing system for coal direct liquefaction oil

Abstract

The application provides a coal direct liquefaction oil hydrogenation treatment system, which comprises a feeding unit, a reactor and a separation unit; the feeding unit is used for conveying coal direct liquefaction oil and hydrogen; the feeding unit is communicated with a feeding port of the reactor, and the coal direct liquefaction oil and the hydrogen enter the reactor to perform a hydrogenation reaction; the separation unit comprises a hot high-pressure separator, a cold high-pressure separator, a filtering separation device, a hot high-oil tank and a fractionating column; the hot high-pressure separator is connected with an outlet of the reactor; the filtering separation device is used for separating hot high-oil liquid phase into hot high-oil liquid and hot high-oil slurry; the hot high-oil liquid enters the hot high-oil tank, and the hot high-oil slurry enters the reactor; the hot high-oil tank and the cold high-pressure separator are connected with the fractionating column. By using the scheme, the problems that solid particles in the coal direct liquefaction oil easily cause abrasion, blockage of valves, pumps and the like in the conveying process of liquefaction circulating solvents and liquefaction oil products, and reduction of the yield and purity of the liquefaction oil products are solved.

Description

Technical Field

[0001] This invention relates to the field of direct coal liquefaction technology, and more specifically, to a hydrogenation treatment system for direct coal liquefaction oil. Background Technology

[0002] In existing direct coal liquefaction technologies, the direct coal liquefaction oil generated from the direct coal liquefaction reactor is usually hydrogenated. Part of the hydrogenated direct coal liquefaction oil is used to prepare liquefied oil products, and the other part is used as raw material for subsequent hydrotreating and refining.

[0003] However, the coal direct liquefaction oil produced from the coal direct liquefaction reactor often contains fine coal powder solid particles. When the coal direct liquefaction oil undergoes hydrotreating, it will also contain fine hydrotreating catalyst solid particles. These fine solid particles will exacerbate the wear of valves, pumps and other devices in the entire hydrotreating system, and at the same time cause blockages in the delivery pipelines, reducing the yield and purity of the liquefaction circulating solvent and liquefied oil. Summary of the Invention

[0004] This invention provides a hydrotreating system for direct coal liquefaction oil to solve the problems in the prior art where solid particles in direct coal liquefaction oil easily lead to wear and blockage of valves, pumps, etc. in the liquefaction circulating solvent and liquefied oil transportation process, as well as a reduction in the yield and purity of liquefied oil.

[0005] According to an embodiment of the present invention, a hydrotreating system for direct coal liquefaction oil is provided. The hydrotreating system for direct coal liquefaction oil includes:

[0006] The feeding unit is used to convey direct coal liquefaction oil and hydrogen.

[0007] The reactor has a feed unit connected to the reactor's inlet, allowing coal liquefaction oil and hydrogen to directly enter the reactor for hydrogenation reaction.

[0008] The separation unit includes a hot high-pressure separator, a cold high-pressure separator, a filtration separation device, a hot high-pressure oil tank, and a fractionation tower. The hot high-pressure separator is connected to the outlet of the reactor and is used to separate the medium input from the reactor into a hot high-pressure gas phase and a hot high-pressure liquid phase. The hot high-pressure gas phase enters the cold high-pressure separator, and the hot high-pressure liquid phase enters the filtration separation device. The cold high-pressure separator is used to separate the hot high-pressure gas phase into a cold high-pressure gas phase and a cold high-pressure oil phase.

[0009] The filtration and separation device is used to separate the hot high-efficiency liquid phase into hot high-efficiency oil and hot high-efficiency oil slurry. The hot high-efficiency oil enters the hot high-efficiency oil tank, and the hot high-efficiency oil slurry enters the reactor.

[0010] Both the hot high-pressure oil tank and the cold high-pressure separator are connected to the fractionation tower, which is used to fractionate the cold high-pressure oil and the hot high-pressure oil to obtain the coal direct liquefaction circulating solvent and liquefied oil products.

[0011] Furthermore, the filtration and separation device includes at least two filters, each filter including a filter housing, a filter element and an extraction-backwash port. The filter element is disposed inside the filter housing, and the extraction-backwash port is disposed on the filter housing. Each extraction-backwash port is connected to a hot high-temperature oil tank, and a first flow control valve is provided on the connecting pipeline between each extraction-backwash port and the hot high-temperature oil tank.

[0012] Furthermore, each filter is used to separate the input medium into hot high-density raw oil and hot high-density raw oil slurry. At least two filters are arranged in series. The hot high-density liquid phase input into the filtration and separation device passes through each filter in sequence. The hot high-density raw oil separated by each filter forms hot high-density oil, which is input into the hot high-density oil tank. The hot high-density raw oil slurry separated by each filter is input into the next filter. The hot high-density raw oil slurry separated by the last filter is the hot high-density oil slurry, which enters the reactor.

[0013] Furthermore, each filter is used to separate the input medium into hot high-density raw oil and hot high-density raw oil slurry. At least two filters are arranged in parallel. The hot high-density liquid phase input into the filtration and separation device passes through each filter. The hot high-density raw oil separated by each filter forms hot high-density oil, which is input into the hot high-density oil tank. The hot high-density raw oil slurry separated by each filter forms hot high-density oil slurry, which enters the reactor.

[0014] Furthermore, the filter housing is cylindrical, and the filter element is coaxially arranged with the filter housing.

[0015] Furthermore, the filter element is an internal pressure membrane filter or an internal pressure cartridge filter, and the filtration accuracy of the filter element is 0.1μm-15μm.

[0016] Furthermore, the separation unit also includes a circulation pump and a backwash tank. The inlet of the circulation pump is connected to the lower outlet of the hot high-pressure separator, and the outlet of the circulation pump is connected to the inlet of the filtration separation device. The backwash tank is connected to the extraction-backwash port of each filter. The backwash tank is used to store and input hydrogen or circulating hydrogen into the filtration separation device. A second flow control valve is installed on the connecting pipeline between the backwash tank and the extraction-backwash port of each filter.

[0017] Furthermore, the separation unit also includes a circulation pump and a backwash tank. The inlet of the circulation pump is connected to the lower outlet of the filtration and separation device, and the outlet of the circulation pump is connected to the first inlet of the reactor. The backwash tank is connected to the extraction-backwash port of each filter. The backwash tank is used to store and input hot high-separation oil into the filtration and separation device. A second flow control valve is installed on the connecting pipeline between the backwash tank and the extraction-backwash port of each filter.

[0018] Furthermore, the feeding unit includes a gas feed pipe, a liquid feed pipe, a gas heater, and a liquid heater. The gas feed pipe is connected to the inlet of the liquid feed pipe and the gas heater, and the liquid feed pipe is connected to the inlet of the liquid heater. The gas feed pipe is used to introduce hydrogen into the gas heater and the liquid heater, and the liquid feed pipe is used to introduce direct coal liquefaction oil into the liquid heater.

[0019] Furthermore, a screen is installed at one end of the reactor connected to the hot high-pressure separator to prevent catalyst particles from flowing out of the reactor, and a distributor is installed at the other end of the reactor to ensure that the hot high-pressure oil slurry entering the reactor is evenly distributed.

[0020] By applying the technical solution of this invention, a hot high-pressure separator is used to initially separate the gas-liquid mixture output from the reactor into a hot high-pressure gas phase and a hot high-pressure liquid phase, which facilitates the separate processing of the hot high-pressure gas phase and the hot high-pressure liquid phase. A cold high-pressure separator further separates the hot high-pressure gas phase into a cold high-pressure gas phase and a cold high-pressure oil phase. A filtration and separation device further separates the hot high-pressure liquid phase into a hot high-pressure oil phase and a hot high-pressure oil slurry. The cold high-pressure oil phase and the hot high-pressure oil phase are then fed into a fractionation tower for further fractionation processing to ensure the purity of the subsequent liquefaction circulating solvent and liquefied oil products.

[0021] The filtration and separation device can prevent hot high-concentration oil slurry with a large concentration of solid particles from entering the subsequent fractionation tower, ensuring the long-term stable operation of the hydrotreating system for direct coal liquefaction oil. The hot high-concentration oil slurry is returned to the reactor as a circulating solvent to participate in subsequent reactions, thereby improving the utilization rate of direct coal liquefaction oil.

[0022] This configuration enables the system to operate continuously, improving the efficiency of direct coal liquefaction oil hydrotreating and solving the problem of low efficiency in existing direct coal liquefaction oil hydrotreating systems. Through precise control of filtration and separation, the content of solid particles carried by the fluid medium in the system is reduced, improving the yield and purity of liquefied circulating solvent and liquefied oil, enhancing the stability and reliability of the entire direct coal liquefaction oil hydrotreating system, reducing equipment wear and pipeline blockage, and extending the service life of the equipment. Attached Figure Description

[0023] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0024] Figure 1 A schematic diagram of a hydrotreating system for direct coal liquefaction oil provided in Embodiment 1 of the present invention is shown.

[0025] Figure 2 A schematic diagram of a hydrotreating system for direct coal liquefaction oil provided in Embodiment 2 of the present invention is shown.

[0026] Figure 3 A schematic diagram of the filter structure is shown;

[0027] Figure 4 A schematic diagram of a filtration separation device with filters arranged in series is shown.

[0028] Figure 5 A schematic diagram of a filtration separation device with filters arranged in parallel is shown.

[0029] The above figures include the following reference numerals:

[0030] 10. Feeding unit; 11. Gas feed pipe; 12. Liquid feed pipe; 13. Gas heater; 14. Liquid heater;

[0031] 20. Reactor;

[0032] 31. Hot high-pressure separator;

[0033] 32. Cold high-pressure separator;

[0034] 33. Filtration and separation device;

[0035] 331. Filter; 3311. Filter housing; 3312. Filter element; 3313. Pull-out / backwash port;

[0036] 34. High-temperature oil separation tank;

[0037] 35. Distillation tower;

[0038] 36. Circulating pump;

[0039] 37. Backwash tank;

[0040] 41. First flow control valve;

[0041] 42. Second flow control valve. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] like Figures 1 to 5 As shown, an embodiment of the present invention provides a hydrotreating system for direct coal liquefaction oil, the system comprising:

[0044] Feeding unit 10 is used to convey coal direct liquefaction oil and hydrogen;

[0045] The feed unit 10 is connected to the feed inlet of the reactor 20, and the coal liquefaction oil and hydrogen enter the reactor 20 for hydrogenation reaction.

[0046] The separation unit includes a hot high-pressure separator 31, a cold high-pressure separator 32, a filtration separation device 33, a hot high-pressure oil tank 34, and a fractionation tower 35. The hot high-pressure separator 31 is connected to the outlet of the reactor 20. The hot high-pressure separator 31 is used to separate the medium input from the reactor 20 into a hot high-pressure gas phase and a hot high-pressure liquid phase. The hot high-pressure gas phase enters the cold high-pressure separator 32, and the hot high-pressure liquid phase enters the filtration separation device 33. The cold high-pressure separator 32 is used to separate the hot high-pressure gas phase into a cold high-pressure gas phase and a cold high-pressure oil phase.

[0047] The filtration and separation device 33 is used to separate the hot high-efficiency liquid phase into hot high-efficiency oil and hot high-efficiency oil slurry. The hot high-efficiency oil enters the hot high-efficiency oil tank 34, and the hot high-efficiency oil slurry enters the reactor 20.

[0048] Both the hot high-pressure oil tank 34 and the cold high-pressure separator 32 are connected to the fractionation tower 35. The fractionation tower 35 is used to fractionate the cold high-pressure oil and the hot high-pressure oil to obtain the coal direct liquefaction circulating solvent and liquefied oil.

[0049] Applying the technical solution of this invention, the gas-liquid mixture output from the reactor 20 is initially separated into a hot high-pressure gas phase and a hot high-pressure liquid phase by a hot high-pressure separator 31, which facilitates the separate processing of the hot high-pressure gas phase and the hot high-pressure liquid phase; the cold high-pressure separator 32 further separates the hot high-pressure gas phase into a cold high-pressure gas and a cold high-pressure oil; the filtration and separation device 33 further separates the hot high-pressure liquid phase into a hot high-pressure oil and a hot high-pressure oil slurry; the cold high-pressure oil and the hot high-pressure oil are fed into the fractionation tower 35 for the next fractionation process to ensure the purity of the subsequent liquefaction circulating solvent and liquefied oil products.

[0050] The filtration and separation device 33 can prevent hot high-concentration oil slurry with a large concentration of solid particles from entering the subsequent fractionation tower 35, ensuring the long-term stable operation of the direct coal liquefaction oil hydrotreating system. The hot high-concentration oil slurry is returned to the reactor 20 as a circulating solvent to participate in subsequent reactions, thereby improving the utilization rate of direct coal liquefaction oil.

[0051] This configuration enables the system to operate continuously, improving the efficiency of direct coal liquefaction oil hydrotreating and solving the problem of low efficiency in existing direct coal liquefaction oil hydrotreating systems. Through precise control of filtration and separation, the content of solid particles carried by the fluid medium in the system is reduced, improving the yield and purity of liquefied circulating solvent and liquefied oil, enhancing the stability and reliability of the entire direct coal liquefaction oil hydrotreating system, reducing equipment wear and pipeline blockage, and extending the service life of the equipment.

[0052] In some embodiments, the reactor 20 is selected as a fluidized bed reactor, which can prevent the catalyst particles in the reactor 20 from flowing out of the reactor 20, and at the same time, it is not easy to generate pressure drop, thus ensuring the working efficiency of the reactor 20.

[0053] like Figure 3 As shown, the filtration and separation device 33 includes at least two filters 331. Each filter 331 includes a filter housing 3311, a filter element 3312, and an extraction-backwash port 3313. The filter element 3312 is disposed inside the filter housing 3311, and the extraction-backwash port 3313 is disposed on the filter housing 3311. Each extraction-backwash port 3313 is connected to the hot high-temperature oil separator 34, and a first flow control valve 41 is provided on the connecting pipeline between each extraction-backwash port 3313 and the hot high-temperature oil separator 34.

[0054] The hot high-precision oil enters the hot high-precision oil tank 34 through the extraction-backwash port 3313, while the hot high-precision oil slurry is returned to the reactor 20 for recycling. This maximizes resource utilization, reduces energy consumption and raw material waste. This setup improves the filtration, separation and recycling of coal direct liquefaction oil in the system, enhances the efficiency of the hydrogenation reaction and the purity of the product, and reduces the risk of pipeline blockage in the system.

[0055] Furthermore, the first flow control valve 41 enables the system to precisely control the flow rate and volume of hot high-temperature oil from the filter 331 into the hot high-temperature oil tank 34, improving the convenience of system maintenance.

[0056] like Figure 4As shown, each filter 331 is used to separate the input medium into hot high-density raw oil and hot high-density raw oil slurry. At least two filters 331 are arranged in series. The hot high-density liquid phase input into the filtration and separation device 33 passes through each filter 331 in sequence. The hot high-density raw oil separated by each filter 331 forms hot high-density oil, which is input into the hot high-density oil tank 34. The hot high-density raw oil slurry separated by each filter 331 is input into the next filter 331. The hot high-density raw oil slurry separated by the last filter 331 is the hot high-density oil slurry, which enters the reactor 20.

[0057] At least two filters 331 are arranged in series, which can filter and separate the hot high-density raw oil slurry multiple times, improve the yield of hot high-density oil, and avoid a large amount of hot high-density oil slurry with low solid particle concentration from repeatedly entering the reactor 20, causing energy waste. At the same time, this design improves the efficiency of the hydrogenation process and product quality, and enhances resource utilization.

[0058] like Figure 5 As shown, each filter 331 is used to separate the input medium into hot high-density raw oil and hot high-density raw oil slurry. At least two filters 331 are arranged in parallel. The hot high-density liquid phase input into the filtration and separation device 33 passes through each filter 331. The hot high-density raw oil separated by each filter 331 forms hot high-density oil, which is input into the hot high-density oil tank 34. The hot high-density raw oil slurry separated by each filter 331 forms hot high-density oil slurry, which enters the reactor 20.

[0059] At least two filters 331 are arranged in parallel, which improves the filtration efficiency of the filtration and separation device 33. Furthermore, parallel processing reduces the workload of a single filter 331, enhancing the stability and reliability of the system. In addition, the parallel structure facilitates system inspection and maintenance. When a single filter 331 in the filtration and separation device 33 needs repair or replacement, it can be operated independently without affecting the normal operation of other filters 331, thus ensuring the continuity and efficiency of the hydrotreating process for direct coal liquefaction oil.

[0060] like Figure 3 As shown, the filter housing 3311 is cylindrical, and the filter element 3312 is coaxially arranged with the filter housing 3311.

[0061] In this embodiment, the filter housing 3311 adopts a cylindrical design, and the filter element 3312 is coaxially configured with it. This structural layout reduces the installation difficulty of the filter 331. At the same time, the cylindrical filter housing 3311 can ensure a more uniform internal fluid distribution, which is beneficial to improving filtration efficiency and reducing local resistance loss.

[0062] Furthermore, the filter element 3312, which is coaxially arranged with the filter housing 3311, enhances the compactness of the system, optimizes the structural layout of the process flow, reduces dead angles in the fluid flow path, improves the continuity and reliability of direct coal liquefaction oil filtration, extends the service life of the direct coal liquefaction oil hydrotreating system, and reduces maintenance costs.

[0063] In some embodiments, the filter element 3312 is an internal pressure membrane filter or an internal pressure cartridge filter, and the filtration accuracy of the filter element 3312 is 0.1μm-15μm.

[0064] This design ensures that solid particles in the hot high-performance liquid phase are effectively intercepted, reducing the solid particle content in the hot high-performance oil. The filtration accuracy of filter element 3312 is 0.1μm-15μm, which helps reduce pipeline blockage in the system, extends the service life of the direct coal liquefaction oil hydrotreating system, and improves the overall system operating efficiency and product quality.

[0065] In some embodiments, the filtration accuracy of the filter element 3312 is 0.1μm-5μm, which can further improve the purity of hot high-precision oil, reduce the content of solid particles in the hot high-precision oil, and improve the filtration and separation effect.

[0066] In Embodiment 1 of this application, the filtration and separation device 33 includes three filters 331 arranged in series. The filter element 3312 is a sintered metal filter cartridge with a filtration accuracy of 1 μm. The reactor 20 is a fluidized bed reactor. The properties of the coal direct liquefaction oil used are shown in Table 1, the hydrogenation reaction conditions in the reactor 20 are shown in Table 2, and the properties of the hot high-precision oil output from the filtration and separation device 33 are shown in Table 3.

[0067] Table 1

[0068]

[0069] Table 2

[0070]

[0071] Table 3

[0072]

[0073] In Embodiment 2 of this application, three filters 331 are connected in parallel, and other conditions are the same as in Embodiment 1. The properties of the hot high-separation oil output by the filtration and separation device 33 are shown in Table 4.

[0074] Table 4

[0075]

[0076] In Comparative Example 1 of this application, no filtration and separation device 33 is provided. Part of the hot high-density liquid phase enters the reactor 20, and part flows to the hot high-density oil tank 34. The medium in the hot high-density oil tank 34 is the hot high-density oil. Other conditions are the same as in Example 1. The properties of the hot high-density oil in the hot high-density oil tank 34 are shown in Table 5.

[0077] Table 5

[0078]

[0079] By comparing the properties of the hot high-precision oil in Examples 1 and 2 with those in Comparative Example 1 in Tables 3 to 5, it can be seen that by adopting the technical solution of the present invention, the hydrogen supply index of the hot high-precision oil is improved, and it does not contain solid particles, which reduces the wear of valves, pumps and other devices in the hydrotreating system, avoids blockage of the delivery pipeline, and improves the yield and purity of liquefied circulating solvent and liquefied oil.

[0080] like Figure 1 As shown, the separation unit also includes a circulation pump 36 and a backwash tank 37. The inlet of the circulation pump 36 is connected to the lower outlet of the hot high-pressure separator 31, and the outlet of the circulation pump 36 is connected to the inlet of the filtration separation device 33. The backwash tank 37 is connected to the extraction-backwash port 3313 of each filter 331. The backwash tank 37 is used to store and input hydrogen or circulating hydrogen into the filtration separation device 33. A second flow control valve 42 is provided on the connecting pipeline between the backwash tank 37 and the extraction-backwash port 3313 of each filter 331.

[0081] The backwash tank 37 is set up to store hydrogen or circulate hydrogen, which makes it easy to control the fluid pressure and flow rate input to the filter separation device 33 according to the actual working conditions. This ensures the uniformity and continuity of the fluid used for backwashing, improves the cleaning efficiency of the filter element 3312, and extends the service life of the filter 331.

[0082] A second flow control valve 42 is provided on the connecting pipeline between the extraction-backwash port 3313 of each filter 331 and the backwash tank 37. The second flow control valve 42 is used in conjunction with the first flow control valve 41.

[0083] Specifically, when the first flow control valve 41 on the connecting pipe of one of the filters 331 is open, the corresponding second flow control valve 42 of that filter 331 is closed. At this time, the hot high-separation oil enters the hot high-separation oil tank 34, and the backwash tank 37 stops supplying hydrogen or circulating hydrogen to the filter 331. When the first flow control valve 41 on the connecting pipe of one of the filters 331 is closed, the corresponding second flow control valve 42 of that filter 331 is open. At this time, the hot high-separation oil stops entering the hot high-separation oil tank 34, and the backwash tank 37 supplies hydrogen or circulating hydrogen to the filter 331 to perform a backwashing operation on the filter 331. During the operation of this filtration and separation device 33, it is necessary to ensure that when the first flow control valve 41 on the connecting pipe of at least one filter 331 is open, the corresponding second flow control valve 42 of that filter 331 is closed to ensure the continuity of the filtration and separation operation and achieve efficient operation of the system.

[0084] Through the action of the circulating pump 36, the hot high-performance liquid phase is pressurized and enters the filtration and separation device 33, which enhances the fluid potential energy of the hot high-performance liquid phase in the filtration and separation device 33, and helps to improve the filtration and separation effect. This combination of circulating pressurization and backwashing mechanism enhances the stability and reliability of the entire coal direct liquefaction oil hydrotreating system, and ensures the continuous and effective treatment of coal direct liquefaction oil.

[0085] like Figure 2 As shown, the separation unit also includes a circulation pump 36 and a backwash tank 37. The inlet of the circulation pump 36 is connected to the lower outlet of the filtration separation device 33, and the outlet of the circulation pump 36 is connected to the first inlet of the reactor 20. The backwash tank 37 is connected to the extraction-backwash port 3313 of each filter 331. The backwash tank 37 is used to store and input hot high-separation oil into the filtration separation device 33. A second flow control valve 42 is provided on the connecting pipeline between the backwash tank 37 and the extraction-backwash port 3313 of each filter 331.

[0086] Through the action of the circulating pump 36, the hot high-precision oil slurry is pressurized and enters the reactor 20, which enhances the fluid potential energy of the hot high-precision oil slurry in the reactor 20 and helps to improve the effect of hydrogenation reaction.

[0087] A backwash tank 37 is provided to store hot high-part oil, facilitating control of the fluid pressure and flow rate input to the filtration and separation device 33 according to actual operating conditions. This ensures the uniformity and continuity of the fluid used for backwashing, improves the cleaning efficiency of the filter element 3312, and extends the service life of the filter 331. Furthermore, the circulating pump 36 is located between the first inlet of the reactor 20 and the lower outlet of the filtration and separation device 33. To prevent cavitation in the circulating pump 36, the medium stored in the backwash tank 37 and input to the filtration and separation device 33 is hot high-part oil, improving the safety and stability of the system.

[0088] A second flow control valve 42 is provided on the connecting pipeline between the extraction-backwash port 3313 of each filter 331 and the backwash tank 37. The second flow control valve 42 is used in conjunction with the first flow control valve 41.

[0089] Specifically, when the first flow control valve 41 on the connecting pipe of one of the filters 331 is open, the corresponding second flow control valve 42 of that filter 331 is closed. At this time, the hot high-grade oil enters the hot high-grade oil tank 34, and the backwash tank 37 stops feeding hot high-grade oil into the filter 331. When the first flow control valve 41 on the connecting pipe of one of the filters 331 is closed, the corresponding second flow control valve 42 of that filter 331 is open. At this time, the hot high-grade oil stops entering the hot high-grade oil tank 34, and the backwash tank 37 feeds hot high-grade oil into the filter 331 to perform a backwashing operation on the filter 331. During the operation of this filtration and separation device 33, it is necessary to ensure that when the first flow control valve 41 on the connecting pipe of at least one filter 331 is open, the corresponding second flow control valve 42 of that filter 331 is closed to ensure the continuity of the filtration and separation operation and achieve efficient operation of the system.

[0090] The combination of this cyclic pressurization and backwashing mechanism enhances the stability and reliability of the entire direct coal liquefaction oil hydrotreating system, ensuring the continuous and effective treatment of direct coal liquefaction oil.

[0091] like Figure 1 , Figure 2 As shown, the feeding unit 10 includes a gas feed pipe 11, a liquid feed pipe 12, a gas heater 13, and a liquid heater 14. The gas feed pipe 11 is connected to the inlet of the liquid feed pipe 12 and the inlet of the gas heater 13. The liquid feed pipe 12 is connected to the inlet of the liquid heater 14. The gas feed pipe 11 is used to introduce hydrogen into the gas heater 13 and the liquid heater 14. The liquid feed pipe 12 is used to introduce direct coal liquefaction oil into the liquid heater 14.

[0092] This design allows hydrogen to be delivered to the gas heater 13 and the liquid heater 14 via the gas feed pipe 11, while direct coal liquefaction oil is fed into the liquid heater 14 via the liquid feed pipe 12. By preheating the hydrogen and direct coal liquefaction oil, suitable feed temperatures are ensured, thereby optimizing the efficiency of the subsequent hydrogenation reaction.

[0093] Specifically, a small amount of hydrogen enters the liquid heater 14 through the gas feed pipe 11 and is heated together with the direct coal liquefaction oil. This can inhibit the coking of the direct coal liquefaction oil on the heating furnace tubes in the liquid heater 14, prevent the tube wall temperature from rising sharply, and avoid a significant reduction in the pressure drop inside the equipment. This improves the safety and reliability of the equipment and extends its service life.

[0094] Furthermore, by directly feeding heated hydrogen and coal-liquefied oil into reactor 20, the contact between the raw materials and the catalyst can be promoted more effectively, the reaction rate can be accelerated, the formation of by-products can be reduced, and the quality and yield of the target oil can be improved.

[0095] In some embodiments, a screen is provided at one end of the reactor 20 connected to the hot high-pressure separator 31 to prevent catalyst particles from flowing out of the reactor 20, and a distributor is provided at the other end of the reactor 20 to ensure that the hot high-pressure oil slurry entering the reactor 20 is evenly distributed.

[0096] In this embodiment, a screen is provided at one end of the reactor 20 that is connected to the hot high-pressure separator 31 to block catalyst particles from flowing out of the reactor 20. This helps to ensure the catalytic effect of the catalyst in the reactor 20, improve its utilization efficiency, reduce the content of solid particles in the hot high-pressure separator gas phase, and reduce the frequency of catalyst replacement and replenishment in the reactor 20.

[0097] A distributor is provided at the other end of the reactor 20 to ensure that the hot high-precision oil slurry entering the reactor 20 can enter the reactor 20 evenly, ensuring that the hot high-precision oil slurry is in full contact with the catalyst, thereby improving the conversion rate of the hydrogenation reaction.

[0098] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0099] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0100] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0101] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0102] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0103] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A hydrotreating system for direct coal liquefaction oil, characterized in that, The hydrotreating system for the direct coal liquefaction oil includes: Feeding unit (10), the feeding unit (10) is used to convey direct coal liquefaction oil and hydrogen; The reactor (20) is connected to the feed inlet of the reactor (20) by the feed unit (10), and the direct coal liquefaction oil and the hydrogen enter the reactor (20) for hydrogenation reaction; The separation unit includes a hot high-pressure separator (31), a cold high-pressure separator (32), a filtration separation device (33), a hot high-pressure oil tank (34), and a fractionation tower (35). The hot high-pressure separator (31) is connected to the outlet of the reactor (20). The hot high-pressure separator (31) is used to separate the medium input from the reactor (20) into a hot high-pressure gas phase and a hot high-pressure liquid phase. The hot high-pressure gas phase enters the cold high-pressure separator (32), and the hot high-pressure liquid phase enters the filtration separation device (33). The cold high-pressure separator (32) is used to separate the hot high-pressure gas phase into a cold high-pressure gas phase and a cold high-pressure oil phase. The filtration and separation device (33) is used to separate the hot high-performance liquid phase into hot high-performance oil and hot high-performance oil slurry. The hot high-performance oil enters the hot high-performance oil tank (34), and the hot high-performance oil slurry enters the reactor (20). The hot high-pressure oil tank (34) and the cold high-pressure separator (32) are both connected to the fractionation tower (35), which is used to fractionate the cold high-pressure oil and the hot high-pressure oil to obtain coal direct liquefaction circulating solvent and liquefied oil.

2. The hydrotreating system for direct coal liquefaction oil according to claim 1, characterized in that, The filtration and separation device (33) includes at least two filters (331). Each filter (331) includes a filter housing (3311), a filter element (3312), and an extraction-backwash port (3313). The filter element (3312) is disposed inside the filter housing (3311), and the extraction-backwash port (3313) is disposed on the filter housing (3311). Each extraction-backwash port (3313) is connected to the hot high-temperature oil tank (34), and a first flow control valve (41) is provided on the connecting pipeline between each extraction-backwash port (3313) and the hot high-temperature oil tank (34).

3. The hydrotreating system for direct coal liquefaction oil according to claim 2, characterized in that, Each filter (331) is used to separate the input medium into hot high-density raw oil and hot high-density raw oil slurry. At least two filters (331) are arranged in series. The hot high-density liquid phase input into the filtration and separation device (33) passes through each filter (331) in sequence. The hot high-density raw oil separated by each filter (331) forms the hot high-density oil, which is input into the hot high-density oil tank (34). The hot high-density raw oil slurry separated by each filter (331) is input into the next filter (331). The hot high-density raw oil slurry separated by the last filter (331) is the hot high-density oil slurry, which enters the reactor (20).

4. The hydrotreating system for direct coal liquefaction oil according to claim 2, characterized in that, Each of the filters (331) is used to separate the input medium into hot high-performance raw oil and hot high-performance raw oil slurry. At least two of the filters (331) are arranged in parallel. The hot high-performance liquid phase input into the filtration and separation device (33) passes through each of the filters (331). The hot high-performance raw oil separated by each of the filters (331) forms the hot high-performance oil, which is input into the hot high-performance oil tank (34). The hot high-performance raw oil slurry separated by each of the filters (331) forms the hot high-performance oil slurry, which enters the reactor (20).

5. The hydrotreating system for direct coal liquefaction oil according to claim 2, characterized in that, The filter housing (3311) is cylindrical, and the filter element (3312) is coaxially arranged with the filter housing (3311).

6. The hydrotreating system for direct coal liquefaction oil according to claim 2, characterized in that, The filter element (3312) is an internal pressure membrane filter or an internal pressure cartridge filter, and the filtration accuracy of the filter element (3312) is 0.1μm-15μm.

7. The hydrotreating system for direct coal liquefaction oil according to claim 2, characterized in that, The separation unit also includes a circulation pump (36) and a backwash tank (37). The inlet of the circulation pump (36) is connected to the lower outlet of the hot high-pressure separator (31), and the outlet of the circulation pump (36) is connected to the inlet of the filter separation device (33). The backwash tank (37) is connected to the extraction-backwash port (3313) of each filter (331). The backwash tank (37) is used to store and input hydrogen or circulating hydrogen into the filter separation device (33). A second flow control valve (42) is provided on the connecting pipeline between the backwash tank (37) and the extraction-backwash port (3313) of each filter (331).

8. The hydrotreating system for direct coal liquefaction oil according to claim 2, characterized in that, The separation unit also includes a circulation pump (36) and a backwash tank (37). The inlet of the circulation pump (36) is connected to the lower outlet of the filter separation device (33), and the outlet of the circulation pump (36) is connected to the first inlet of the reactor (20). The backwash tank (37) is connected to the extraction-backwash port (3313) of each filter (331). The backwash tank (37) is used to store and input hot high-fraction oil into the filter separation device (33). A second flow control valve (42) is provided on the connecting pipeline between the backwash tank (37) and the extraction-backwash port (3313) of each filter (331).

9. The hydrotreating system for direct coal liquefaction oil according to claim 1, characterized in that, The feeding unit (10) includes a gas feed pipe (11), a liquid feed pipe (12), a gas heater (13), and a liquid heater (14). The gas feed pipe (11) is connected to the inlet of the liquid feed pipe (12) and the gas heater (13). The liquid feed pipe (12) is connected to the inlet of the liquid heater (14). The gas feed pipe (11) is used to introduce hydrogen into the gas heater (13) and the liquid heater (14). The liquid feed pipe (12) is used to introduce direct coal liquefaction oil into the liquid heater (14).

10. The hydrotreating system for direct coal liquefaction oil according to claim 1, characterized in that, A screen is provided at one end of the reactor (20) connected to the hot high-pressure separator (31) to prevent catalyst particles from flowing out of the reactor (20). A distributor is provided at the other end of the reactor (20) to ensure that the hot high-pressure oil slurry entering the reactor (20) is evenly distributed.

Images