Hydrogenation method and system for crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbon
Through the multi-stage hydrogenation method, the treatment of crude benzene, cracked gasoline, naphtha and stable light hydrocarbons, the problem of difficult heat control of the hydrogenation reaction in the prior art is solved, and the stable control of temperature and the improvement of product yield is achieved.
Patent Information
- Application Number
- CN202411961114.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-03-28
AI Technical Summary
Prior art In the hydrogenation reaction of crude benzene, cracked gasoline, naphtha and stable light hydrocarbons, it is difficult to control the heat released by the reaction, resulting in the out of control of the reaction.
The multi-stage hydrogenation method is adopted, and the cracked gasoline and stable light hydrocarbons are treated by the first liquid phase hydrogenation device and the second liquid phase hydrogenation device, respectively, the reaction temperature is controlled, and the hydrogenation reaction is carried out with hydrogen gas using a catalyst.
The temperature of the hydrogenation reaction is effectively controlled, the yield of pure benzene is increased, energy consumption is reduced, and the utilization rate of raw materials is improved.
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Figure CN119709266A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of chemical hydrogenation, and in particular relates to a hydrogenation method and a system for crude benzene, cracked gasoline, naphtha and stable light hydrocarbons. Background Art
[0002] Crude benzene is mainly composed of benzene and its compounds, in addition to less unsaturated hydrocarbons such as benzene, toluene and meta-xylene, as well as sulfides, nitrides and oxides. Pyrolysis gasoline is rich in aromatics, and also contains diolefins, monoolefins, a small amount of straight-chain alkanes and cycloalkanes, as well as trace amounts of sulfur, oxygen, chlorine and heavy metals. The main components of naphtha include pentane, hexane and heptane. The commonly used technology for crude benzene is coking hydrogenation, which is to process the raw coal into coal gas and then use extraction technology to convert it into crude benzene. After removing the waste, the organic compounds with higher density are directly stored as by-products of the process. For substances with lower density, they are first passed through a booster to increase their pressure, and then fully mixed with hydrogen, and then hydrogenated to separate the inorganic compounds into an evaporator. Secondly, the inorganic compounds are separated through a two-stage reactor and directly stored. Finally, the crude benzene that has undergone hydrogenation is sent to the extraction process to separate the aromatics, and finally the products required by the factory are obtained. For the hydrogenation of pyrolysis gasoline, a two-stage hydrogenation method is used, in which one stage of hydrogenation is to convert easily polymerizable dienes into monoolefins, including the conversion of alkenyl aromatics into aromatics. The second stage of hydrogenation is to further saturate the monoolefins, and impurities such as oxygen, sulfur, and nitrogen are removed by hydrogenation. For the hydrogenation of petroleum naphtha, hydrogen is reacted with benzene in the raw material at low pressure to produce other ideal components such as cyclohexane, and then the deep desulfurization, debenzenization and denitrogenation reactions of naphtha are carried out under closed and high pressure. However, since crude benzene, pyrolysis gasoline, naphtha, and stable light hydrocarbons are all oily mixtures, the components are complex and the differences are large, and the proportion of unsaturated hydrocarbons such as olefins contained is large. Therefore, if the hydrogenation reaction is carried out together, the heat released by the reaction is difficult to control or leads to loss of control. Therefore, the existing technology needs further changes. Summary of the invention
[0003] The object of the present invention is to provide a hydrogenation method and system for crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons.
[0004] Based on the above purpose, the present invention adopts the following technical solutions: A method for hydrogenating crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons, comprising the following steps: (1) After the cracked gasoline and / or stable light hydrocarbons are mixed and filtered, they are heated at 40-45°C for 3-5s, then heated to 45-50°C for 3-5s, and then heated to 70-75°C for 3-5s, and then hydrogenated with a catalyst and hydrogen in a first liquid phase hydrogenation device at 100-105°C for 10-20s to obtain a hydrogenated liquid material; (2) After filtering the crude benzene and / or naphtha, heat it to 68-72°C for 3-5 seconds, continue to heat it to 68-72°C for 3-5 seconds, continue to heat it to 138-142°C for 3-5 seconds, and then react with the catalyst and hydrogen in a liquid phase hydrogenation device at 173-177°C for 10-20 seconds to obtain a hydrogenated liquid material; (3) The liquid material after hydrogenation is heated to 145-150°C, and after 3-5 seconds, the temperature is raised to 190-195°C, and maintained for 3-5 seconds. After that, the light components with carbon atoms less than 10 are vaporized, and the vaporized gas is collected. The liquid material is further heated to 200-205°C for 2-3 seconds, and then hydrogenated with a catalyst and hydrogen at 214-218°C for 10-20 seconds, and then heated to 273-277°C for 2-3 seconds, and then hydrogenated with a catalyst and hydrogen at 300-324°C to remove sulfides, nitrides, and oxides, and generate hydrogen sulfide, ammonia, and water. The temperature is lowered by 30-32°C for fractionation to obtain by-products, pentane, cyclopentane, crude naphthalene, non-aromatic hydrocarbons, xylene, and the main product is pure benzene.
[0005] Furthermore, the catalyst is cobalt molybdenum, nickel molybdenum, or zirconium molybdenum.
[0006] A hydrogenation method using the crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons, comprising a pyrolysis gasoline storage device and a stable light hydrocarbon storage device, wherein the discharge port of the pyrolysis gasoline storage device and the discharge port of the stable light hydrocarbon storage device are connected to the feed port of a light hydrocarbon feed buffer tank, the discharge port of the light hydrocarbon feed buffer tank is connected to the feed port of a first heat exchanger, the discharge port of the light hydrocarbon feed buffer tank is connected to the feed port of the first heat exchanger, and a hydrogenation device and a charred air conveying device are also arranged between the discharge port of the first heat exchanger and the first feed port of the second heat exchanger, the first discharge port of the second heat exchanger is connected to the feed port of a first heater, the discharge port of the first heater is connected to the feed port of a first liquid phase hydrogenation reactor, the discharge port of the first liquid phase hydrogenation reactor is connected to the second feed port of a second heat exchanger, the second discharge port of the second heat exchanger is connected to the feed port of a first heater, the discharge port of the first heater is connected to the feed port of a first liquid phase hydrogenation reactor, the discharge port of the first liquid phase hydrogenation reactor is connected to the second feed port of a second heat exchanger, the second discharge port of the second heat exchanger is connected to the feed port of a first liquid phase hydrogenation reactor, the discharge port of the first liquid phase hydrogenation reactor is connected to the second The second feed port of a heat exchanger, the first discharge port of the first heat exchanger is connected to the feed port of the first cooler, the discharge port of the first cooler is connected to the feed port of the first cold high-pressure separation tank, the gas outlet of the first cold high-pressure separation tank is connected to the third heat exchanger, the liquid outlet of the cold high-pressure separation tank is connected to the hydrogenation oil tank, the pre-evaporator and the feed port of the third heat exchanger, the feed port of the third heat exchanger is also connected to the pressure reducing tower, the discharge port of the third heat exchanger is connected to the feed port of the pre-reverse feed steam heater, the discharge port of the hydrogenation oil steam heater is connected to the feed port of the pre-hydrogenation reactor, the hydrogenation port of the pre-hydrogenation reactor is connected to the cold hydrogen conveying device, the discharge port of the pre-hydrogenation reactor is connected to the feed port of the fourth heat exchanger, the discharge port of the fourth heat exchanger is connected to the feed port of the first electric heater, the discharge port of the first electric heater is connected to the feed port of the main hydrogenation reactor, the discharge port of the main hydrogenation reactor The inlet of the main hydrogenation reactor is connected to the cold hydrogen delivery device, the outlet of the fourth heat exchanger heat source is connected to the inlet of the fifth heat exchanger heat source, the outlet of the fifth heat exchanger heat source is connected to the inlet of the third heat exchanger heat source, the outlet of the third heat exchanger heat source is connected to the inlet of the pre-evaporator heat source, the outlet of the pre-evaporator heat source is connected to the inlet of the seventh heat exchanger heat source, the outlet of the seventh heat exchanger heat source is connected to the inlet of the sixth heat exchanger heat source, the outlet of the sixth heat exchanger heat source is connected to the feed inlet of the main reaction product air cooler, the outlet of the main reaction product air cooler is connected to the feed inlet of the first main reaction product water cooler, the outlet of the first main reaction product water cooler is connected to the feed inlet of the second main reaction product water cooler, the outlet of the second main reaction product water cooler is connected to the second cold high-pressure separation tank, and the crude benzene storage device and the naphtha storage device are connected to the crude benzene The feed inlet of the hydrogenation feed buffer tank and the discharge outlet of the crude benzene hydrogenation feed buffer tank are connected to the feed inlet of the sixth heat exchanger, the discharge outlet of the sixth heat exchanger is connected to the feed inlet of the fifth heat exchanger, the discharge outlet of the fifth heat exchanger is connected to the feed inlet of the second electric heater, the discharge outlet of the second electric heater is connected to the liquid inlet of the second liquid phase hydrogenation reactor, the discharge outlet of the second liquid phase hydrogenation reactor is connected to the feed inlet of the pre-evaporator, the discharge outlet of the pre-evaporator is connected to the feed inlet of the evaporation tower, the bottom oil outlet of the evaporation tower is connected to the oil inlet of the vacuum tower, the gas outlet of the evaporation tower is connected to the feed inlet of the fifth heat exchanger, the discharge outlet of the fifth heat exchanger is connected to the feed inlet of the pre-reverse feed steam heater, the gas outlet of the vacuum tower is connected to the feed inlet of the water cooler at the top of the vacuum tower, the discharge outlet of the water cooler at the top of the vacuum tower is connected to the feed inlet of the reflux tank of the vacuum tower, and the discharge outlet of the reflux tank of the vacuum tower is connected to the reflux outlet of the vacuum tower,The liquid outlet of the vacuum tower is connected to the feed port of the heavy component water cooler, the water cooling outlet of the heavy component is connected to the crude naphthalene storage tank, and the outlet of the vacuum tower reflux tank is also connected to the feed port of the third heat exchanger.
[0007] Furthermore, a plurality of first filters are provided between the discharge port of the cracked gasoline storage device and the discharge port of the stable light hydrocarbon storage device and the feed port of the light hydrocarbon feed buffer tank, and the discharge port of the buffer tank is also connected to the polymerization inhibitor feed port.
[0008] Furthermore, the buffer tank is also provided with a nitrogen replenishment port and an exhaust port, and the buffer tank discharge port is also connected to the buffer tank feed port.
[0009] Furthermore, a plurality of first filters are provided between the outlet of the cracked gasoline storage device and the outlet of the stable light hydrocarbon storage device and the feed inlet of the light hydrocarbon feed buffer tank.
[0010] Furthermore, a nitrogen delivery device and a charred air delivery device are provided between the first heater outlet and the first liquid phase hydrogenation reactor feed port.
[0011] Furthermore, the first cold high-pressure separation tank is also provided with a charred air exhaust port.
[0012] The present invention can realize the simultaneous hydrorefining of crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons as raw materials. After the pyrolysis gasoline and stable light hydrocarbons are preliminarily treated with unsaturated hydrocarbons such as olefins by the first liquid phase hydrogenation reactor, and at the same time, after the crude benzene and / or naphtha are preliminarily treated with unsaturated hydrocarbons such as olefins by the second liquid phase hydrogenation reactor, it is beneficial to control the temperature in the pre-hydrogenation reactor and the main hydrogenation reactor to be stable, to achieve stable production, and to improve the product yield and by-product yield. The present invention recovers the heat in the heating process, reduces energy consumption, and multi-stage hydrogenation can thereby improve the yield of pure benzene. It is also possible to recover by-products in the hydrogenation reaction process to improve the utilization rate of raw materials. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a position relationship diagram of the pyrolysis gasoline storage device and the stable light hydrocarbon storage device; Figure 2 This is the position relationship diagram of the vacuum tower and the vacuum tower top water cooler; Figure 3 This is a diagram showing the location relationship between the crude benzene storage unit and the naphtha storage unit. DETAILED DESCRIPTION Example
[0014] A method for hydrogenating crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons, characterized in that it consists of the following steps: (1) After the cracked gasoline and / or stable light hydrocarbons are mixed and filtered, they are heated at 40-45°C for 3-5s, then heated to 45-50°C for 3-5s, and then heated to 70-75°C for 3-5s, and then hydrogenated with a catalyst and hydrogen in a first liquid phase hydrogenation device at 100-105°C for 10-20s to obtain a hydrogenated liquid material; (2) After filtering the crude benzene and / or naphtha, heat it to 68-72°C for 3-5 seconds, continue to heat it to 68-72°C for 3-5 seconds, continue to heat it to 138-142°C for 3-5 seconds, and then react with the catalyst and hydrogen in a liquid phase hydrogenation device at 173-177°C for 10-20 seconds to obtain a hydrogenated liquid material; (3) The liquid material after hydrogenation is heated to 145-150°C, and after 3-5 seconds, the temperature is raised to 190-195°C, and maintained for 3-5 seconds. After that, the light components with carbon atoms less than 10 are vaporized, and the vaporized gas is collected. The liquid material is further heated to 200-205°C for 2-3 seconds, and then hydrogenated with a catalyst and hydrogen at 214-218°C for 10-20 seconds, and then heated to 273-277°C for 2-3 seconds, and then hydrogenated with a catalyst and hydrogen at 300-324°C to remove sulfides, nitrides, and oxides, and generate hydrogen sulfide, ammonia, and water. The temperature is lowered by 30-32°C for fractionation to obtain by-products, pentane, cyclopentane, crude naphthalene, non-aromatic hydrocarbons, xylene, and the main product is pure benzene.
[0015] like Figure 1-3A hydrogenation system for crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons is shown, comprising a pyrolysis gasoline storage device 1 and a stable light hydrocarbon storage device 2, wherein the pyrolysis gasoline storage device discharge port 101 and the stable light hydrocarbon storage device discharge port 201 are connected to the light hydrocarbon feed buffer tank feed port 301, the light hydrocarbon feed buffer tank discharge port 302 is connected to the first heat exchanger feed port 401, and the light hydrocarbon feed buffer tank discharge port 302 is connected to the first heat exchanger feed port 401. A hydrogenation device 44 and a charred air conveying device 45 are also arranged between them, the first heat exchanger first discharge port 402 is connected to the second heat exchanger first discharge port 501, the second heat exchanger first discharge port 502 is connected to the first heater feed port 601, and the first heater discharge port 602 is connected to the first liquid phase hydrogenation reactor The first liquid phase hydrogenation reactor feed port 701 is connected to the second heat exchanger feed port 503, the second heat exchanger second feed port 504 is connected to the first heat exchanger second feed port 403, the first heat exchanger first feed port 404 is connected to the first cooler feed port 801, the first cooler feed port 802 is connected to the first cold high pressure separation tank feed port 901, the first cold high pressure separation tank gas outlet 904 is connected to the third heat exchanger 11, the cold high pressure separation tank liquid outlet 902 is connected to the hydrogenation oil tank 13, the pre-evaporator 2403 and the third heat exchanger feed port 1101, the third heat exchanger feed port 1101 is also connected to the vacuum tower 16, the third heat exchanger discharge port 1102 is connected to the pre-reverse feed steam heater feed port 1701, the hydrogenation oil steam The heater outlet 1702 is connected to the pre-hydrogenation reactor feed port 1801, the pre-hydrogenation reactor hydrogenation port 1803 is connected to the cold hydrogen conveying device 19, the pre-hydrogenation reactor outlet 1802 is connected to the fourth heat exchanger feed port 2001, the fourth heat exchanger outlet 2002 is connected to the first electric heater feed port 2101, the first electric heater outlet 2102 is connected to the main hydrogenation reactor feed port 2201, the main hydrogenation reactor outlet 2202 is connected to the fourth heat exchanger heat source inlet 2003, the main hydrogenation reactor air inlet 2203 is connected to the cold hydrogen conveying device 19, the fourth heat exchanger heat source outlet 2004 is connected to the fifth heat exchanger heat source inlet 2301, the fifth heat exchanger heat source outlet 2302 is connected to the third heat exchanger heat source inlet 1103, and the third The heat source outlet 1104 of the heat exchanger is connected to the heat source inlet 2401 of the pre-evaporator, the heat source outlet 2402 of the pre-evaporator is connected to the heat source inlet 2501 of the seventh heat exchanger, the heat source outlet 2502 of the seventh heat exchanger is connected to the heat source inlet 3601 of the sixth heat exchanger, the heat source outlet 3602 of the sixth heat exchanger is connected to the feed inlet 3701 of the main reaction product air cooler, the discharge port 3702 of the main reaction product air cooler is connected to the feed inlet 3801 of the first main reaction product water cooler, the discharge port 3802 of the first main reaction product water cooler is connected to the feed inlet 3901 of the second main reaction product water cooler, the discharge port 3902 of the second main reaction product water cooler is connected to the second cold high-pressure separation tank 40, the crude benzene storage device 41 and the naphtha storage device 42 are connected to the feed inlet 4301 of the crude benzene hydrogenation feed buffer tank,The discharge port 4302 of the crude benzene hydrogenation feed buffer tank is connected to the sixth heat exchanger feed port 3603, the sixth heat exchanger discharge port 3604 is connected to the fifth heat exchanger feed port 2503, the fifth heat exchanger discharge port 2504 is connected to the second electric heater feed port 2601, the second electric heater discharge port 2602 is connected to the second liquid phase hydrogenation reactor liquid inlet 2701, the second liquid phase hydrogenation reactor discharge port 2702 is connected to the pre-evaporator feed port 2403, the pre-evaporator discharge port 2404 is connected to the evaporation tower feed port 2801, the evaporation tower bottom oil outlet 2802 is connected to the vacuum tower oil inlet 1604, and the evaporation tower gas outlet 2803 The fifth heat exchanger feed port 2303 is connected, the fifth heat exchanger discharge port 2304 is connected to the pre-reverse feed steam heater feed port 1701, the vacuum tower gas outlet 1601 is connected to the vacuum tower top water cooler feed port 2901, the vacuum tower top water cooler gas outlet 2902 is connected to the vacuum tower reflux tank feed port 3001, the vacuum tower reflux tank discharge port 3002 is connected to the vacuum tower reflux port 1603, the vacuum tower liquid outlet 1602 is connected to the heavy component water cooler feed port 3201, the heavy component water cooling discharge port 3202 is connected to the crude naphthalene storage tank 33, and the vacuum tower reflux tank discharge port 3002 is also connected to the third heat exchanger feed port 1101. Several first filters 31 are also arranged between the pyrolysis gasoline storage device discharge port 101 and the stable light hydrocarbon storage device discharge port 201 and the light hydrocarbon feed buffer tank feed port 301, and the buffer tank discharge port is also connected to the inhibitor feed port. The buffer tank 3 is also provided with a nitrogen replenishment port 303 and an exhaust port 304, and the buffer tank discharge port 302 is also connected to the buffer tank feed port 301. Several first filters 31 are also provided between the pyrolysis gasoline storage device discharge port 101 and the stable light hydrocarbon storage device discharge port 201 and the light hydrocarbon feed buffer tank feed port 301. A nitrogen delivery device 46 and a charred air delivery device 45 are also provided between the first heater discharge port 602 and the first liquid phase hydrogenation reactor feed port 701. A charred air exhaust port 47 is also provided on the first cold high-pressure separation tank 9.
[0016] When in use, firstly, the pyrolysis gasoline is stored in the pyrolysis gasoline storage device 1, the light hydrocarbons are stored in the stable light hydrocarbon storage device 2, the crude benzene is stored in the crude benzene storage device 41, and the naphtha is stored in the naphtha storage device 42. After the cracked gasoline and / or light hydrocarbons enter the first filter 31 for filtration, the solid impurities are filtered out, and then the cracked gasoline and / or light hydrocarbons enter the light hydrocarbon feed buffer tank 3 for buffering to ensure the stability of the feed. The buffer tank 3 is also provided with a nitrogen replenishing port 303 and an exhaust port 304. The cracked gasoline and / or light hydrocarbons flow into the first heat exchanger 4 from the buffer tank outlet 302 and are heated to 40-45°C. They enter the second heat exchanger 5 from the first feed port 501 of the second heat exchanger and continue to be heated to 45-50°C. Then, they enter the first heater 6 and are heated to 70-75°C. Then, they enter the first liquid phase hydrogenation reactor 7 for hydrogenation reaction. At the same time, the reaction temperature of the first liquid phase hydrogenation reactor 7 is 100-105°C, and the unsaturated hydrocarbons and olefins are heated to 40-45°C. The hydrocarbon undergoes hydrogenation reaction to generate alkane, and then enters the shell side of the second heat exchanger 5 from the second feed port 503 of the second heat exchanger, cools to 85-90°C, and then enters the shell side of the first heat exchanger from the second feed port 403 of the first heat exchanger, cools to 75-80°C, and then enters the first cooler 8, cools to 38-43°C, and then enters the first cold high-pressure separation tank 9. The hydrogen after the reaction enters the third heat exchanger from the first cold high-pressure separation tank outlet 904, and then enters the third heat exchanger heat source inlet 1103 to enter the third heat exchanger shell side to cool to 254-258°C. The burnt air enters 47, and the liquid phase material enters the high-pressure separation tank outlet 902. After the liquid phase comes out from the high-pressure separator 902, it enters the third heat exchanger 11, and can enter the pre-evaporator 24 according to the working conditions. Or the hydrogenation oil tank 13 is used for buffering. After the third heat exchanger shell side is cooled, it comes out from the third heat exchanger heat source outlet 1104 and enters the pre-evaporator 24 from the pre-evaporator heat source inlet 2401 to cool to 184-188°C. The pre-evaporator discharge port 2404 is connected to the evaporation tower feed port 2801, and then enters the evaporator 28 from the evaporation tower feed port 2801 to heat 190-195°C. The light component is less than C10 and is connected to the fifth heat exchanger feed port 2303 from the evaporation tower outlet 2803. It enters the fifth heat exchanger 23 from the tube side and is heated to 200-205°C. It then enters the pre-reverse feed steam heater 17 tube side and is heated to 214-218°C. After entering the pre-hydrogenation reactor from the pre-hydrogenation reactor feed port 1801, hydrogen is added to react to convert the light component into Olefins are hydrogenated to produce saturated alkanes, and then enter the fourth heat exchanger tube from the fourth heat exchanger feed port 2001 to be heated to 273-277°C. When the temperature is lower than 277°C, the first electric heater 21 is turned on to heat to 277°C. If the temperature is reached, the first electric heater heating function is not turned on, and the olefins are directly entered from the main hydrogenation reactor feed port 2201 to be heated to 300-324°C. Catalysts are added therein for re-hydrogenation, and impurities such as sulfides, nitrides, and oxides are removed to generate impurities such as hydrogen sulfide, ammonia, and water. The olefins are discharged from the main hydrogenation reactor outlet 2202 and enter the fourth heat exchanger heat source inlet 2003 to be cooled to 290-295°C, and enter the fifth heat exchanger 23 from the fifth heat exchanger heat source inlet 2301.The temperature is reduced to 264-268°C, and then enters the third heat exchanger shell from the third heat exchanger heat source inlet 1103 to cool to 254-258°C, and then enters the pre-evaporator heat source 24 shell from the pre-evaporator heat source inlet 2401 to cool to 184-188°C, and then continues to cool to 135-137°C in the seventh heat exchanger heat source inlet 2501, and then comes out from the seventh heat exchanger heat source outlet 2502 and enters the sixth heat exchanger heat source inlet 3601. The temperature is reduced to 132-134°C in the six heat exchangers, and then enters the product air cooler 37 from the product air cooler feed port 3701 to cool down to 40-45°C, and then enters the first main product water cooler 38 and the second main product water cooler to cool down to 31°C, and then enters the second cold high-pressure separation tank 40 to separate C4 and gaseous light components, as well as impurities such as hydrogen sulfide, ammonia, and water, retaining 80-90% of aromatics and 8-12% of alkanes, and then the fractionation system.
[0017] The evaporator bottom oil outlet 2802 enters the vacuum tower 16 through the vacuum tower oil inlet 1604 to remove weight and reduce pressure, and the heavy benzene C10 and above comes out from the vacuum tower liquid outlet 1602 (154-158°C in the vacuum tower) and enters the heavy component water cooler 32 to be cooled to (33-35°C) and enters the crude naphthalene storage tank 33. Crude benzene is stored in the crude benzene storage device 41 and the naphtha storage device 42 and enters the crude benzene hydrogenation feed buffer tank. Crude benzene and / or naphtha enter the benzene hydrogenation feed buffer tank 43 and then exit from the crude benzene hydrogenation feed buffer tank outlet 4302 and enter the sixth heat exchanger 36 from the sixth heat exchanger feed port 3603, and then enter the seventh heat exchanger feed port 2503, and be heated to 68-72°C. From the seventh heat exchanger outlet 2504, it enters the second electric heater 26 and is heated to 138-142°C. It then enters the second liquid phase hydrogenation reactor 27 for preliminary hydrogenation at a reaction temperature of 173-177°C. After hydrogenation of unsaturated hydrocarbons in crude benzene and naphtha, crude benzene and naphtha are generated. Saturated hydrocarbons 8-10% and benzene 80-90% enter the pre-evaporator 24 from the pre-evaporator feed port 2403 and are heated to 168-172°C. They enter the evaporation tower 28 from the evaporation tower feed port 2801 and are heated to 188-192°C. The light components within C10 are vaporized, and they come out from the evaporation tower outlet 2803 and enter the fifth heat exchanger 23 from the fifth heat exchanger feed port 2303 to be heated to 206-208°C. Then, they enter the hydrogenation oil steam heater 17 to continue to be heated to 215-219°C, and then enter the pre-hydrogenation reactor 18 from the pre-hydrogenation reactor feed port 1801 to be heated to 238-242°C, and enter the hydrogenation reaction again. , hydrogenate the unsaturated hydrocarbons into saturated hydrocarbons and benzene 80-90%, and then enter the fourth heat exchanger 20 from the outlet 1802 of the pre-hydrogenation reactor and heat it to 273-277°C from the feed port 2001 of the fourth heat exchanger, and then enter the first electric heater 21 to heat it to 280°C-284°C, and then enter the main hydrogenation reactor to continue hydrogenation to remove olefins, unsaturated hydrocarbons, and impurities such as sulfur, nitrogen, and oxygen. The reaction temperature in the hydrogenation is 309-313°C, and then enter the fourth heat exchanger 20 from the outlet 2202 of the main hydrogenation reactor from the heat source inlet 2003 of the fourth heat exchanger, cool down to 281-285°C, and then exit from the heat source outlet 2004 of the fourth heat exchanger. The heat source inlet 2301 of the fifth heat exchanger enters the fifth heat exchanger 23 and cools down to 258-262°C. It comes out from the heat source outlet 2302 of the fifth heat exchanger and comes out from the heat source inlet 1103 of the third heat exchanger to enter the third heat exchanger and cool down to 248-252°C. It comes out from the heat source outlet 1104 of the third heat exchanger and enters the pre-evaporator 24 from the heat source inlet 2401 of the pre-evaporator to cool down to 184-188°C. It then enters the heat source inlet 2501 of the seventh heat exchanger and continues to cool down to 135-137°C. It then comes out from the heat source outlet 2502 of the seventh heat exchanger and enters the sixth heat exchanger from the heat source inlet 3601 to cool down to 132-134°C.Enter the reverse product air cooler 37 from the reverse product air cooler feed port 3701 to cool down to 40-45°C, then enter the first main reverse product water cooler 38 and the second main reverse product water cooler to cool down to 31°C, and then enter the second cold high-pressure separation tank 40 to remove olefins, unsaturated hydrocarbons, and 80-90% of aromatic hydrocarbons and 8-12% of alkanes containing impurities such as sulfur, nitrogen and oxygen, and then the fractionation system. The yield of pure benzene after fractionation is 74%, by-products: pentane yield: 1.9%, cyclopentane yield: 2%, crude naphthalene yield: 2.3%, non-aromatic hydrocarbons: yield 4%, xylene: yield 16%. An evaporation tower bottom reboiler gas device 40 is also provided between the evaporation tower feed port 2801 and the evaporation tower bottom oil outlet 2802.
Claims
1. A method for hydrogenating crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons, characterized in that: It consists of the following steps: (1) After the cracked gasoline and / or stable light hydrocarbons are mixed and filtered, they are heated at 40-45°C for 3-5s, then heated to 45-50°C for 3-5s, and then heated to 70-75°C for 3-5s, and then hydrogenated with a catalyst and hydrogen in a first liquid phase hydrogenation device at 100-105°C for 10-20s to obtain a hydrogenated liquid material; (2) After filtering the crude benzene and / or naphtha, heat it to 68-72°C for 3-5 seconds, continue to heat it to 68-72°C for 3-5 seconds, continue to heat it to 138-142°C for 3-5 seconds, and then react with the catalyst and hydrogen in a liquid phase hydrogenation device at 173-177°C for 10-20 seconds to obtain a hydrogenated liquid material; (3) The liquid material after hydrogenation is heated to 145-150°C, and after 3-5 seconds, the temperature is raised to 190-195°C, and maintained for 3-5 seconds. After that, the light components with carbon atoms less than 10 are vaporized, and the vaporized gas is collected. The liquid material is further heated to 200-205°C for 2-3 seconds, and then hydrogenated with a catalyst and hydrogen at 214-218°C for 10-20 seconds, and then heated to 273-277°C for 2-3 seconds, and then hydrogenated with a catalyst and hydrogen at 300-324°C to remove sulfides, nitrides, and oxides, and generate hydrogen sulfide, ammonia, and water. The temperature is lowered by 30-32°C for fractionation to obtain by-products, pentane, cyclopentane, crude naphthalene, non-aromatic hydrocarbons, xylene, and the main product is pure benzene.
2. The hydrogenation method of crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons according to claim 1, characterized in that: The catalyst is cobalt molybdenum, nickel molybdenum, or zirconium molybdenum.
3. A system using the hydrogenation method of crude benzene, pyrolysis gasoline, naphtha and stable light hydrocarbons according to claim 1, characterized in that: The invention comprises a pyrolysis gasoline storage device and a stable light hydrocarbon storage device, wherein the discharge port of the pyrolysis gasoline storage device and the discharge port of the stable light hydrocarbon storage device are connected to the feed port of the light hydrocarbon feed buffer tank, the discharge port of the light hydrocarbon feed buffer tank is connected to the feed port of the first heat exchanger, and the discharge port of the light hydrocarbon feed buffer tank is connected to the feed port of the first heat exchanger. A hydrogenation device and a charred air conveying device are also arranged between the discharge port of the light hydrocarbon feed buffer tank and the feed port of the first heat exchanger, the first discharge port of the first heat exchanger is connected to the first feed port of the second heat exchanger, the first discharge port of the second heat exchanger is connected to the feed port of the first heater, the discharge port of the first heater is connected to the feed port of the first liquid phase hydrogenation reactor, the discharge port of the first liquid phase hydrogenation reactor is connected to the second feed port of the second heat exchanger, the second discharge port of the second heat exchanger is connected to the second feed port of the first heat exchanger, and the first discharge port of the first heat exchanger is connected to the first cooling device. The feed port of the first cooler is connected to the feed port of the first cold high-pressure separation tank, the gas outlet of the first cold high-pressure separation tank is connected to the third heat exchanger, the liquid outlet of the cold high-pressure separation tank is connected to the hydrogenation oil tank, the pre-evaporator and the feed port of the third heat exchanger, the feed port of the third heat exchanger is also connected to the vacuum tower, the discharge port of the third heat exchanger is connected to the feed port of the pre-reverse feed steam heater, the discharge port of the hydrogenation oil steam heater is connected to the feed port of the pre-hydrogenation reactor, the hydrogenation port of the pre-hydrogenation reactor is connected to the cold hydrogen conveying device, the discharge port of the pre-hydrogenation reactor is connected to the feed port of the fourth heat exchanger, the discharge port of the fourth heat exchanger is connected to the feed port of the first electric heater, the discharge port of the first electric heater is connected to the feed port of the main hydrogenation reactor, the discharge port of the main hydrogenation reactor is connected to the heat source inlet of the fourth heat exchanger, and the gas inlet of the main hydrogenation reactor is connected to The cooling hydrogen conveying device, the heat source outlet of the fourth heat exchanger is connected to the heat source inlet of the fifth heat exchanger, the heat source outlet of the fifth heat exchanger is connected to the heat source inlet of the third heat exchanger, the heat source outlet of the third heat exchanger is connected to the heat source inlet of the pre-evaporator, the heat source outlet of the pre-evaporator is connected to the heat source inlet of the seventh heat exchanger, the heat source outlet of the seventh heat exchanger is connected to the heat source inlet of the sixth heat exchanger, the heat source outlet of the sixth heat exchanger is connected to the feed inlet of the main reaction product air cooler, the main reaction product air cooler outlet is connected to the feed inlet of the first main reaction product water cooler, the first main reaction product water cooler outlet is connected to the feed inlet of the second main reaction product water cooler, the second main reaction product water cooler outlet is connected to the second cold high-pressure separation tank, the crude benzene storage device and the naphtha storage device are connected to the feed inlet of the crude benzene hydrogenation feed buffer tank, the crude benzene hydrogenation feed buffer tank The discharge port is connected to the feed port of the sixth heat exchanger, the discharge port of the sixth heat exchanger is connected to the feed port of the fifth heat exchanger, the discharge port of the fifth heat exchanger is connected to the feed port of the second electric heater, the discharge port of the second electric heater is connected to the liquid inlet of the second liquid phase hydrogenation reactor, the discharge port of the second liquid phase hydrogenation reactor is connected to the feed port of the pre-evaporator, the discharge port of the pre-evaporator is connected to the feed port of the evaporation tower, the bottom oil outlet of the evaporation tower is connected to the oil inlet of the vacuum tower, the gas outlet of the evaporation tower is connected to the feed port of the fifth heat exchanger, the discharge port of the fifth heat exchanger is connected to the feed port of the pre-reverse feed steam heater, the gas outlet of the vacuum tower is connected to the feed port of the vacuum tower top water cooler, the discharge port of the vacuum tower top water cooler is connected to the feed port of the vacuum tower reflux tank, the discharge port of the vacuum tower reflux tank is connected to the reflux port of the vacuum tower, the liquid outlet of the vacuum tower is connected to the feed port of the heavy component water cooler,The water-cooled discharge port of the heavy component is connected to the crude naphthalene storage tank, and the discharge port of the vacuum tower reflux tank is also connected to the feed port of the third heat exchanger.
4. The hydrogenation system according to claim 3, characterized in that: A plurality of first filters are arranged between the discharge port of the cracked gasoline storage device and the discharge port of the stable light hydrocarbon storage device and the feed port of the light hydrocarbon feed buffer tank, and the discharge port of the buffer tank is also connected to the polymerization inhibitor feed port.
5. The hydrogenation system according to claim 4, characterized in that: The buffer tank is also provided with a nitrogen replenishing port and an exhaust port, and the buffer tank discharge port is also connected to the buffer tank feed port.
6. The hydrogenation method according to claim 5, characterized in that A plurality of first filters are also arranged between the discharge port of the cracked gasoline storage device and the discharge port of the stable light hydrocarbon storage device and the feed port of the light hydrocarbon feed buffer tank.
7. The hydrogenation system according to claim 6, characterized in that: A nitrogen delivery device and a charred air delivery device are also provided between the first heater outlet and the first liquid phase hydrogenation reactor feed port.
8. The hydrogenation system according to claim 7, characterized in that: The first cold high-pressure separation tank is also provided with a charred air exhaust port.