Low-carbon diesel oil hydrofining system and process

Abstract

The invention discloses a low-carbon diesel oil hydrofining system and process. The low-carbon diesel oil hydrofining system comprises a feeding device, a heating device and a refining device. The feeding device is used for inputting diesel oil; the heating device comprises a heater, a first heat exchanger and a second heat exchanger, a tube pass of the first heat exchanger communicates with a tube pass of the second heat exchanger, and the heater communicates with a shell pass of the second heat exchanger and is used for conducting shock wave heating on a heat exchange medium; the refining device comprises a hydrogenation reactor, a desulfurization stripping tower and a fractionating tower; diesel oil is heated by the heating device and then sequentially passes through the hydrogenation reactor, a shell pass of the first heat exchanger, the desulfurization stripping tower and the fractionating tower to obtain refined diesel oil; according to the system, the principle of shock wave heating is utilized, a fuel combustion mode is not needed, generation of carbon dioxide and sulfide is reduced, meanwhile, a refining route is reasonably designed, heat energy is more effectively utilized, and energy consumption is reduced.

Description

Technical Field

[0001] The present application belongs to the field of petrochemical technology, and specifically relates to a low-carbon diesel hydrorefining system and process. Background Art

[0002] Diesel hydrofining refers to the process of improving the quality of oil products by passing diesel and hydrogen through the catalyst bed in the reactor under certain temperature, pressure, hydrogen-to-oil ratio and air velocity conditions. The non-hydrocarbon compounds such as sulfur, nitrogen and oxygen contained in the oil are converted into corresponding hydrocarbons and easily removable hydrogen sulfide, ammonia and water under the action of the hydrofining catalyst. The diesel used for hydrofining needs to be preheated before the hydrogenation reaction. In the prior art, the heating of diesel is usually carried out by thermal radiation. The diesel passes through the furnace tube of the heating furnace, and the combustible gas is continuously introduced into the radiation chamber of the heating furnace. The thermal radiation generated by the gas combustion continuously flushes the furnace tube to achieve the purpose of diesel heating. However, a large amount of carbon dioxide and some sulfides will be generated during the combustion process, which is not conducive to environmental protection. Summary of the invention

[0003] In view of the above-mentioned defects or shortcomings, the present application provides a low-carbon diesel hydrotreating system and process, which aims to solve the technical problems of carbon dioxide and sulfide emissions caused by existing diesel hydrotreating systems based on combustion heating.

[0004] To achieve the above-mentioned purpose, the present application provides a low-carbon diesel hydrotreating refining system, comprising a feeding device, a heating device and a refining device; the feeding device is used to input diesel; the heating device comprises a heater, a first heat exchanger and a second heat exchanger, the tube side of the first heat exchanger is connected to the tube side of the second heat exchanger, the heater is connected to the shell side of the second heat exchanger and is used to perform shock wave heating on the heat exchange medium; the refining device comprises a hydrogenation reactor, a desulfurization stripping tower and a fractionation tower, and the diesel is heated by the heating device and sequentially passes through the hydrogenation reactor, the shell side of the first heat exchanger, the desulfurization stripping tower and the fractionation tower to obtain refined diesel.

[0005] In an embodiment of the present application, the system also includes a first mixer, which is arranged between the hydrogenation reactor and the second heat exchanger and is used to mix diesel and hydrogen. The hydrogenation reactor is provided with a first discharge port and a second discharge port, the first discharge port is connected to the shell side of the first heat exchanger, and the second discharge port is connected to the first mixer.

[0006] In an embodiment of the present application, the feeding device includes a buffer tank and a booster pump, and the booster pump is used to introduce the diesel collected in the buffer tank into the pipe side of the first mixer at a preset pressure.

[0007] In an embodiment of the present application, the heating module further includes a second mixer, there are multiple heaters and they are all connected to the second mixer one by one, and the second mixer is used to collect the heat exchange medium discharged from the multiple heaters and introduce it into the shell side of the heat exchanger.

[0008] In an embodiment of the present application, the heating device further includes a waste heat collector, which is used to reintroduce the heat exchange medium discharged from the heat exchanger into the heater.

[0009] In an embodiment of the present application, the heater includes an outer shell, a first fixed blade grid, a rotating blade grid, a second fixed blade grid and a rotor. The outer shell forms a shock wave heating channel. The cross-section of the shock wave heating channel is annular. The first fixed blade grid, the rotating blade grid and the second fixed blade grid are arranged in sequence from front to back in the shock wave heating channel. The rotor is arranged on the outer shell to drive the rotating blade grid to rotate in the shock wave heating channel.

[0010] In an embodiment of the present application, the heater also includes a plurality of partitions arranged in the shock wave heating channel, the plurality of partitions are used to separate a plurality of heating spaces, each heating space is provided with a plurality of first fixed blades for forming a first fixed blade grid, and a plurality of second fixed blades for forming a second fixed blade grid.

[0011] In the embodiment of the present application, both the first stationary blade and the second stationary blade have a curved streamline profile.

[0012] In an embodiment of the present application, the installation angle of the first fixed blade is between 35° and 75°, the inlet angle of the first fixed blade is between 0° and 45°, and the outlet angle of the first fixed blade is between 35° and 75°; the installation angle of the second fixed blade is between 45° and 85°, the inlet angle of the second fixed blade is between 25° and 65°, and the outlet angle of the second fixed blade is between 25° and 65°.

[0013] In the embodiment of the present application, the rotating blade grid includes a plurality of rotating blades, and each rotating blade has a curved profile toward its rotation direction.

[0014] In the embodiment of the present application, the installation angle of the rotating blade is between 10° and 80°, the inlet angle of the rotating blade is between 35° and 75°, and the outlet angle of the rotating blade is between 35° and 75°.

[0015] To achieve the above purpose, the present application also provides a low-carbon diesel hydrorefining process, comprising:

[0016] S1: The heat exchange medium enters the shell side of the second heat exchanger after being heated to a preset temperature by shock waves;

[0017] S2: Diesel enters the hydrogenation reactor after undergoing convection heat exchange through the tube side of the first heat exchanger and the tube side of the second heat exchanger;

[0018] S3: The hydrogenation reactor separates a first stream and a second stream;

[0019] S4: the first stream passes through the shell side of the first heat exchanger, the desulfurization stripping tower and the fractionation tower in sequence to obtain refined diesel;

[0020] S5: The second stream is mixed with diesel and hydrogen and then re-enters the hydrogenation reactor.

[0021] In the embodiment of the present application, the preset temperature is between 600-1200°C.

[0022] In the embodiment of the present application, step S1 further includes: collecting and circulating the heat exchange medium discharged from the second heat exchanger.

[0023] Through the above technical solution, the low-carbon diesel hydrotreating system provided in the embodiment of the present application has the following beneficial effects:

[0024] When the above-mentioned low-carbon diesel hydrotreating refining system is used, in the system, the diesel passes through the first heat exchanger, the second heat exchanger, the hydrogenation reactor, the desulfurization stripping tower, and the distillation tower in sequence along the pipeline to obtain refined diesel. In the first heat exchanger, the diesel after the hydrogenation reaction is used to conduct preliminary waste heat to fully utilize the thermal energy. In the second heat exchanger, the diesel after preliminary preheating conducts convection heat exchange with the heat exchange medium. The heating process of the heat exchange medium utilizes the principle of shock wave heating. In the heater, the heat exchange medium is decelerated from sonic or supersonic speed to subsonic speed. In this process, the kinetic energy of the heat exchange medium is converted into thermal energy. Compared with the prior art using fuel combustion, this process does not involve chemical changes, does not produce carbon dioxide or sulfide, and is beneficial to environmental protection. At the same time, through the reasonable design of the refining route, thermal energy is more effectively utilized and energy consumption is reduced.

[0025] Other features and advantages of the present application will be described in detail in the subsequent specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide an understanding of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present application but do not constitute a limitation to the present application. In the accompanying drawings:

[0027] Figure 1 is a schematic diagram of a low-carbon diesel hydrotreating system according to an embodiment of the present application;

[0028] Figure 2 is a schematic structural diagram of a heater according to an embodiment of the present application;

[0029] Figure 3 is a front schematic diagram of a heater according to an embodiment of the present application;

[0030] Figure 4 is a schematic diagram of a blade at a certain location in a shock wave heating channel according to an embodiment of the present application;

[0031] Figure 5 It is a flow chart of a low-carbon diesel hydrorefining process according to one embodiment of the present application.

[0032] Description of Reference Numerals

[0033] 10 Hydrogenation reactor 20 Desulfurization stripping tower

[0034] 30 distillation tower 40 heater

[0035] 41 outer shell 42 first fixed blade row

[0036] 43 Rotating blade 44 Second fixed blade

[0037] 45 shock wave heating channel 51 first heat exchanger

[0038] 52 Second heat exchanger 61 First mixer

[0039] 62 Second mixer 70 Booster pump

[0040] 80 Buffer tank DETAILED DESCRIPTION

[0041] The specific embodiments of the present application are described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0042] The low-carbon diesel hydrotreating system and process of the present application will be described below with reference to the accompanying drawings.

[0043] The present application provides a novel low-carbon diesel hydrotreating system. Figure 1 As shown, in a specific embodiment, the low-carbon diesel hydrotreating system includes:

[0044] A feeding device, used for inputting diesel;

[0045] The heating device comprises a heater 40, a first heat exchanger 51 and a second heat exchanger 52, wherein the tube side of the first heat exchanger 51 is connected to the tube side of the second heat exchanger 52, and the heater 40 is connected to the shell side of the second heat exchanger 52 and is used to perform shock wave heating on the heat exchange medium;

[0046] The refining device includes a hydrogenation reactor 10, a desulfurization stripping tower 20 and a fractionation tower 30. The diesel is heated by the heating device and sequentially passes through the hydrogenation reactor 10, the shell side of the first heat exchanger 51, the desulfurization stripping tower 20 and the fractionation tower 30 to obtain refined diesel.

[0047] When the above-mentioned low-carbon diesel hydrotreating refining system is used, the diesel passes through the first heat exchanger 51, the second heat exchanger 52, the hydrogenation reactor 10, the desulfurization stripping tower 20, and the distillation tower 30 in sequence along the pipeline to obtain refined diesel. In the first heat exchanger 51, the diesel after the hydrogenation reaction is preliminarily preheated for the newly introduced diesel to fully utilize the thermal energy. In the second heat exchanger 52, the preliminarily preheated diesel and the heat exchange medium are subjected to convection heat exchange. The heating process of the heat exchange medium utilizes the principle of shock wave heating. In the heater 40, the heat exchange medium is decelerated from the sonic or supersonic speed to the subsonic speed. In this process, the kinetic energy of the heat exchange medium is converted into thermal energy. Compared with the prior art using fuel combustion, this process does not involve chemical changes, does not produce carbon dioxide or sulfide, and is beneficial to environmental protection. At the same time, through the reasonable design of the refining route, thermal energy is more effectively utilized and energy consumption is reduced.

[0048] It should be noted that in the present application, the heater 40 utilizes the principle of shock wave heating. Shock wave is a gas dynamic phenomenon. For gas flowing at the speed of sound or supersonic speed, its speed will be faster than the conduction of its pressure, thereby superimposing to form waves, and when the rear gas passes through these waves, compression waves or expansion waves will be formed. When the gas in the sonic or supersonic state encounters an obstacle, its compression waves will be superimposed to form a shock wave, which can cause the gas temperature to rise sharply and the speed to drop. In essence, part of the kinetic energy of the gas is converted into internal energy.

[0049] like Figure 1 As shown, in the embodiment of the present application, the system further includes a first mixer 61, which is disposed between the hydrogenation reactor 10 and the second heat exchanger 52 and is used to mix diesel and hydrogen. The hydrogenation reactor 10 is provided with a first discharge port and a second discharge port, the first discharge port is connected to the shell side of the first heat exchanger 51, and the second discharge port is connected to the first mixer 61. As the diesel reacts with hydrogen in the reactor, the concentration of the diesel will also decrease, thereby reducing the reaction rate. In order to ensure the efficiency of diesel hydrofining, the materials in the reactor are diverted, and the reacted diesel flows out along the first discharge port to continue the subsequent process. The unreacted diesel enters the first mixer 61 along the second discharge port, and is remixed with the newly introduced diesel and hydrogen before entering the reactor to continue the reaction, thereby achieving the purpose of increasing the reaction rate.

[0050] like Figure 1 As shown, in the embodiment of the present application, the feeding device includes a buffer tank 80 and a booster pump 70. The booster pump 70 is used to introduce the diesel collected in the buffer tank 80 into the pipe of the first mixer 61 at a preset pressure. The buffer tank 80 is used to reduce the unevenness of the flow in the pipeline and improve the suction performance of the booster pump 70. The booster pump 70 pressurizes the input diesel to ensure the normal flow of the fluid in the system.

[0051] In the embodiment of the present application, the heating module also includes a second mixer 62. The number of heaters 40 is multiple and all are connected to the second mixer 62 one by one. The second mixer 62 is used to collect the heat exchange medium discharged from the multiple heaters 40 and introduce it into the shell side of the heat exchanger. The present application adopts a combined heating method of multiple heaters 40, so a single heater 40 can be miniaturized to facilitate its installation. When the heating temperature of the diesel needs to be adjusted, only some of the heaters 40 need to be turned on or off to effectively control the temperature within a certain range; the second mixer 62 mixes the heat exchange medium discharged from the multiple heaters 40 and guides it to the heat exchange chamber at the same rate, so that the airflow in the heat exchange chamber is more stable.

[0052] In the embodiment of the present application, the heating module also includes a waste heat collector, which is used to reintroduce the heat exchange medium discharged from the heat exchanger into the heater 40. Through the waste heat collector, the low-carbon diesel hydrotreating system can recover and utilize heat energy to the maximum extent, and the heat exchange medium discharged from the heat exchange chamber is reintroduced into the heater 40 through the waste heat recovery device, so that it participates in the heating process again, thereby reducing energy waste and heat loss, and improving the energy utilization efficiency of the device. This recycling design helps to save energy and reduce carbon emissions, and is in line with the principle of low-carbon environmental protection.

[0053] Specifically, the low-carbon diesel hydrotreating system also includes a cooler, which is arranged between the reactor and the high-pressure separator. The reaction product is cooled to a specified temperature by the cooler and then flows into the high-pressure separator.

[0054] like Figure 2 As shown, in the embodiment of the present application, the heater 40 includes an outer shell 41, a first fixed blade cascade 42, a rotating blade cascade 43, a second fixed blade cascade 44 and a rotor. The outer shell 41 is formed with a shock wave heating channel 45. The cross section of the shock wave heating channel 45 is annular. The first fixed blade cascade 42, the rotating blade cascade 43, and the second fixed blade cascade 44 are sequentially arranged in the shock wave heating channel 45 from front to back. The rotor is arranged on the outer shell 41 to drive the rotating blade cascade 43 to rotate in the shock wave heating channel 45. With the rotation of the rotating blade cascade 43, the heat exchange medium enters from the inlet of the first fixed blade cascade 42 at a subsonic speed, is accelerated to a sonic speed or a supersonic speed by the rotating blade cascade 43, and then impacts the second fixed blade cascade 44. In the process of impacting the second fixed blade cascade 44, part of the kinetic energy of the heat exchange medium is converted into heat energy, and then flows out along the second fixed blade cascade 44. The rotor is driven by electric energy, so that the heat exchange medium first obtains kinetic energy in the heater 40 and then converts the kinetic energy into thermal energy. The source of electric energy can be clean energy such as wind energy, hydrogen energy, nuclear energy, etc., which is more low-carbon and environmentally friendly.

[0055] Specifically, the first fixed blade cascade 42 and the second fixed blade cascade 44 can be adjusted, and the relative spacing between the first fixed blade cascade 42 and the second fixed blade cascade 44 can be specifically set according to the speed of the heat exchange medium to meet the need for accelerating the heat exchange medium. Further, the first fixed blade cascade 42 and the second fixed blade cascade 44 constitute an air duct for the flow of the heat exchange medium. At the first fixed blade cascade 42, the air duct is set in a reduced manner. When the heat exchange medium passes through the first fixed blade, it is compressed by the air duct for initial acceleration, and then further accelerated to the speed of sound or supersonic speed under the high-speed rotation of the rotating blade cascade 43.

[0056] In the embodiment of the present application, the heater 40 further includes a plurality of partitions disposed in the shock wave heating channel 45, the plurality of partitions being used to separate a plurality of heating spaces, each of which is provided with a plurality of first fixed blades for constituting the first fixed blade cascade 42, and a plurality of second fixed blades for constituting the second fixed blade cascade 44. Although the heat exchange medium can achieve the purpose of heating after impacting the second fixed blade, the temperature increase is limited. In order to meet the actual needs of diesel heating, a plurality of heating spaces are separated by providing a plurality of partitions, so that the heat exchange medium passes through the plurality of heating spaces in the shock wave heating channel 45 in sequence. Through this multi-layer design, the heat exchange medium moves spirally along the shock wave heating channel 45 under the drive of the rotating blades, and repeatedly passes through the first fixed blade cascade 42, the rotating blade cascade 43, and the second fixed blade cascade 44, thereby generating shock waves multiple times and gradually increasing the temperature until the requirement is met.

[0057] Specifically, refer to Figure 2 and Figure 3 The heater 40 is arranged in a circular shape as a whole, the shock wave heating channel surrounds the central axis of the heater 40, the first fixed blade 42, the rotating blade 43 and the second fixed blade 44 also surround the central axis, and the heater 40 also includes a rotor arranged through the central axis, and the rotor drives the rotating blade 43 to rotate around the central axis. The heat exchange medium flows in from the inlet of the outer shell 41, flows along the first fixed blade in the first heating space to the rotating blade 43, and is accelerated from subsonic speed to sonic speed or supersonic speed through the rotating blade 43, and then impacts the second fixed blade in the heating space and slows down to subsonic speed. In this process, part of the kinetic energy of the heat exchange medium is converted into internal energy, completing the first heating. The heat exchange medium after deceleration enters the bladeless area in the next heating space along the second fixed blade, and then flows along the annular bladeless area to the first fixed blade, and performs the second heating according to the above steps. Repeat the above process, the heat exchange medium enters from the inlet of the outer shell 41, and spirally moves along the shock wave heating channel 45 to the outlet of the outer shell 41. In this moving process, the heat exchange medium is repeatedly heated until it reaches the preset temperature. It should be noted that the inlet and the outlet of the outer shell 41 are respectively arranged at the front and rear sides of the outer shell 41 to correspond to the first fixed blade cascade 42 and the second fixed blade cascade 44 respectively.

[0058] Furthermore, the preset temperature of the heat exchange medium entering the shell side of the second heat exchanger is between 600-1200°C, and the specific temperature needs to be set according to the actual needs of diesel heating. The method for adjusting the temperature can be to change the number of heaters 40 in a working state, or to change the rotation speed of the rotating blade 43 to change the maximum speed of the heat exchange medium. The faster the speed of the heat exchange medium, the greater the kinetic energy, and the more internal energy is converted when impacting the second fixed blade.

[0059] In the embodiment of the present application, both the first stationary blade and the second stationary blade have a curved streamline profile.

[0060] In an embodiment of the present application, the installation angle of the first fixed blade is between 35° and 75°, the inlet angle of the first fixed blade is between 0° and 45°, and the outlet angle of the first fixed blade is between 35° and 75°; the installation angle of the second fixed blade is between 45° and 85°, the inlet angle of the second fixed blade is between 25° and 65°, and the outlet angle of the second fixed blade is between 25° and 65°.

[0061] In the embodiment of the present application, the rotating blade grid 43 includes a plurality of rotating blades, and each rotating blade has a curved profile facing its rotation direction.

[0062] In the embodiment of the present application, the installation angle of the rotating blade is between 10° and 80°, the inlet angle of the rotating blade is between 35° and 75°, and the outlet angle of the rotating blade is between 35° and 75°.

[0063] refer to Figure 4 , Figure 4 From left to right, there are the first fixed blade of the first fixed blade 42, the rotating blade of the rotating blade 43, and the second fixed blade of the second fixed blade 44. The heat exchange medium moves along the flow channel formed by the three. The angle settings of the first fixed blade, the rotating blade, and the second fixed blade are optimized to achieve effective heating of the heat exchange medium. Specifically, the specific angle settings of the first fixed blade, the rotating blade, and the second fixed blade can be optimized and selected according to the fluid dynamics requirements and the heating effect. By reasonably setting the installation angles of the first fixed blade, the rotating blade, and the second fixed blade, the heat exchange medium can flow smoothly between the rotating blade and the fixed blade, thereby effectively introducing or exporting the heat exchange medium into or out of the heating space. When selecting the installation angle, factors such as the speed and flow direction of the heat exchange medium, as well as the gap and shape between the blades, can be considered to ensure the best fluid dynamics performance and heat transfer effect.

[0064] To achieve the above purpose, the present application also provides a low-carbon diesel hydrorefining process, comprising:

[0065] S1: The heat exchange medium enters the shell side of the second heat exchanger 52 after being heated to a preset temperature by the shock wave;

[0066] S2: The diesel enters the hydrogenation reactor 10 after undergoing convection heat exchange through the tube side of the first heat exchanger 51 and the tube side of the second heat exchanger 52;

[0067] S3: The hydrogenation reactor 10 splits a first stream and a second stream;

[0068] S4: the first stream passes through the shell side of the first heat exchanger 51, the desulfurization stripping tower 20 and the fractionation tower 30 in sequence to obtain refined diesel;

[0069] S5: The second material stream is mixed with diesel and hydrogen and then re-enters the hydrogenation reactor 10.

[0070] In the embodiment of the present application, the preset temperature is between 600-1200°C.

[0071] In the embodiment of the present application, step S1 further includes: collecting the heat exchange medium discharged from the second heat exchanger 52 and circulating it. Specifically, the heat exchange medium can be air, nitrogen, water vapor, etc.

[0072] The following are specific examples and comparative examples of the present application.

[0073] Example 1

[0074] Taking a 2 million tons / year low-carbon diesel hydrotreating system as an example, the initial temperature of the diesel is 20°C, the temperature of the diesel after heating is 225°C, and the required heat load is 57,000KW. The first fixed blade 42 includes 40 first fixed blades, the second fixed blade 44 includes 40 second fixed blades, and the rotating blade 43 includes 80 rotating blades. The installation angle of the first fixed blade is 56.5°, the inlet angle is 1°, and the outlet angle is 49.9°; the installation angle of the second fixed blade is 75.52°, the inlet angle is 54.12°, and the outlet angle is 35.4°; the installation angle of the rotating blade is 74.7°, the inlet angle is 42.7°, and the outlet angle is 41.87. The rotating blade 43 rotates at a speed of 7500rpm, the heat exchange medium is air, the speed of air entering the heater 40 is 115m / s, and the air is heated from 25°C to 870°C by the heater 40. The number of heaters 40 is three. In this system, carbon emissions from diesel heating are negligible.

[0075] Comparative Example 1

[0076] Taking the hydrotreating of 2 million tons / year of raw diesel as an example, the initial temperature of the diesel is 40°C, the temperature of the diesel after heating is 350°C, the branch temperature difference does not exceed 10°C, the temperature in the radiation chamber does not exceed 800°C, the fuel used is methane, and the annual carbon emissions are about 80,000 tons / year.

[0077] Example 2

[0078] Taking the hydrofining of 1.4 million tons / year of low-carbon diesel as an example, the initial temperature of the diesel is 40°C, the temperature of the diesel after heating is 260°C, and the required heat load is 38,000KW. The first fixed blade 42 includes 36 first fixed blades, the second fixed blade 44 includes 36 second fixed blades, and the rotating blade 43 includes 72 rotating blades. The installation angle of the first fixed blade is 56.5°, the inlet angle is 1°, and the outlet angle is 49.9°; the installation angle of the second fixed blade is 75.52°, the inlet angle is 54.12°, and the outlet angle is 35.4°; the installation angle of the rotating blade is 74.7°, the inlet angle is 42.7°, and the outlet angle is 41.87. The rotating blade 43 rotates at a speed of 7500rpm, the heat exchange medium is air, the speed of air entering the heater 40 is 115m / s, and the air is heated from 25°C to 850°C by the heater 40. The number of heaters 40 is two. In this system, carbon emissions from diesel heating are negligible.

[0079] Comparative Example 2

[0080] Taking the hydrotreating of 1.4 million tons / year of raw diesel as an example, the initial temperature of the diesel is 40°C, the temperature of the diesel after heating is 350°C, the branch temperature difference does not exceed 15°C, the temperature in the radiation room does not exceed 820°C, the fuel used is methane, and the annual carbon emissions are approximately 5,500 tons.

[0081] Through the above-mentioned embodiments and comparative examples, the low-carbon diesel hydrofining system of the present application not only achieves the purpose of diesel hydrofining but also reduces the generation of carbon dioxide and sulfide, which is beneficial to environmental protection.

[0082] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0083] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0084] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0085] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A low-carbon diesel hydrotreating system, characterized in that: include: A feeding device, used for inputting diesel; A heating device, comprising a heater (40), a first heat exchanger (51) and a second heat exchanger (52), wherein the tube side of the first heat exchanger (51) is connected to the tube side of the second heat exchanger (52), and the heater (40) is connected to the shell side of the second heat exchanger (52) and is used to perform shock wave heating on the heat exchange medium; The refining device comprises a hydrogenation reactor (10), a desulfurization stripping tower (20) and a fractionation tower (30). After being heated by the heating device, the diesel oil passes through the hydrogenation reactor (10), the shell side of the first heat exchanger (51), the desulfurization stripping tower (20) and the fractionation tower (30) in sequence to obtain refined diesel oil.

2. The low-carbon diesel hydrotreating system according to claim 1, characterized in that: The system further comprises a first mixer (61), which is arranged between the hydrogenation reactor (10) and the second heat exchanger (52) and is used for mixing diesel and hydrogen. The hydrogenation reactor (10) is provided with a first discharge port and a second discharge port, wherein the first discharge port is connected to the shell side of the first heat exchanger (51), and the second discharge port is connected to the first mixer (61).

3. The low-carbon diesel hydrotreating system according to claim 2, characterized in that: The feeding device comprises a buffer tank (80) and a booster pump (70), wherein the booster pump (70) is used to introduce the diesel collected in the buffer tank (80) into the pipe side of the first mixer (61) at a preset pressure.

4. The low-carbon diesel hydrotreating system according to claim 1, characterized in that: The heating module further comprises a second mixer (62), the number of the heaters (40) is multiple and all are connected to the second mixer (62) one by one, and the second mixer (62) is used to collect the heat exchange medium discharged from the multiple heaters (40) and introduce it into the shell side of the heat exchanger.

5. The low-carbon diesel hydrotreating system according to claim 4, characterized in that: The heating device further comprises a waste heat collector, which is used to reintroduce the heat exchange medium discharged from the heat exchanger into the heater (40).

6. The low-carbon diesel hydrotreating system according to claim 1, characterized in that: The heater (40) comprises an outer shell (41), a first fixed blade grid (42), a rotating blade grid (43), a second fixed blade grid (44) and a rotor. The outer shell (41) forms a shock wave heating channel (45). The cross section of the shock wave heating channel (45) is annular. The first fixed blade grid (42), the rotating blade grid (43) and the second fixed blade grid (44) are sequentially arranged in the shock wave heating channel (45) from front to back. The rotor is arranged on the outer shell (41) to drive the rotating blade grid (43) to rotate in the shock wave heating channel (45).

7. The low-carbon diesel hydrotreating system according to claim 6, characterized in that: The heater (40) further comprises a plurality of partitions arranged in the shock wave heating channel (45), the plurality of partitions being used to separate a plurality of heating spaces, each of the heating spaces being provided with a plurality of first fixed blades for constituting the first fixed blade grid (42), and a plurality of second fixed blades for constituting the second fixed blade grid (44).

8. The low-carbon diesel hydrotreating system according to claim 7, characterized in that: The first stationary blade and the second stationary blade each have a curved streamline profile.

9. The low-carbon diesel hydrotreating system according to claim 8, characterized in that: The installation angle of the first fixed blade is between 35° and 75°, the inlet angle of the first fixed blade is between 0° and 45°, and the outlet angle of the first fixed blade is between 35° and 75°; the installation angle of the second fixed blade is between 45° and 85°, the inlet angle of the second fixed blade is between 25° and 65°, and the outlet angle of the second fixed blade is between 25° and 65°.

10. The low-carbon diesel hydrotreating system according to claim 7, characterized in that: The rotating blade grid (43) comprises a plurality of rotating blades, each of which has a curved profile facing its rotation direction.

11. The low-carbon diesel hydrotreating system according to claim 10, characterized in that: The installation angle of the rotating blade is between 10° and 80°, the inlet angle of the rotating blade is between 35° and 75°, and the outlet angle of the rotating blade is between 35° and 75°.

12. A low-carbon diesel hydrorefining process, characterized in that: The process comprises: S1: The heat exchange medium is heated to a preset temperature by the shock wave and then enters the shell side of the second heat exchanger (52); S2: The diesel enters the hydrogenation reactor (10) after undergoing convection heat exchange through the tube side of the first heat exchanger (51) and the tube side of the second heat exchanger (52); S3: the hydrogenation reactor (10) separates a first stream and a second stream; S4: the first material stream passes through the shell side of the first heat exchanger (51), the desulfurization stripping tower (20) and the fractionation tower (30) in sequence to obtain refined diesel; S5: The second material stream is mixed with diesel and hydrogen and then re-enters the hydrogenation reactor (10).

13. The low-carbon diesel hydrorefining process according to claim 12, characterized in that: In the step S1, the preset temperature is between 600-1200°C.

14. The low-carbon diesel hydrorefining process according to claim 12, characterized in that: The step S1 further comprises: collecting the heat exchange medium discharged from the second heat exchanger (52) and circulating it.

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