Process for the production of high octane gasoline from catalytic cracking of hydrocarbons and reaction system thereof

Abstract

The application relates to a method for producing high-octane gasoline from catalytic cracking of hydrocarbons and a reaction system thereof, which comprises the following steps: in an isokinetic fluidized bed reactor, light petroleum hydrocarbons such as diesel oil are contacted with a high-silicon-aluminum-ratio catalytic cracking catalyst, and through regeneration flue gas circulation, self-heating balance is maintained to produce liquefied gas and high-octane gasoline. The method of the application can process not only diesel oil and other light hydrocarbons, but also naphtha, wax oil and residual oil and other heavy oils, the diesel oil conversion rate is high, and self-heating balance can be realized, so that the problem of excess production capacity of refinery diesel oil is solved, and the crude oil processing benefit is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of catalytic cracking of petroleum hydrocarbons, and in particular to a method and a reaction system for producing high-octane gasoline. BACKGROUND

[0002] In recent years, the consumption ratio of diesel to gasoline in the product oil market has been continuously decreasing, and the diesel consumption reached a peak of 176 Mt in 2014 and then showed zero growth or negative growth. According to statistics, the unit mileage emission of a heavy-duty diesel vehicle is about 150 times that of a light-duty gasoline vehicle at the same stage, and the annual emission is about 750 times that of a light-duty gasoline vehicle at the same stage. This pollution situation further restricts the development of diesel vehicles. It is predicted that by 2025, the diesel consumption will decrease to 168 Mt, and the consumption ratio of diesel to gasoline will decrease from the current 1.4 to less than 1. This will mean that there will be more than 100 million tons of excess gasoline and diesel products, and the high particulate matter emission of diesel engines further restricts the use of diesel, and the excess of millions of tons of vehicle diesel in a thousand tons of refinery will be more than a million tons. Reducing the diesel to gasoline ratio of refinery products and finding a way out for diesel have become urgent problems to be solved. Straight-run diesel accounts for about 50% of the total diesel, and reducing the production of straight-run diesel or converting it into other high-value-added products to adapt to the changes in future diesel demand has great significance for ensuring the balance between supply and demand in the product oil market in China.

[0003] For the conversion of straight-run diesel, light diesel oil can be blended in the ethylene cracking feedstock at 10% or less, but compared with other light feedstocks, the steam cracking olefin yield of straight-run diesel is lower, and the decoking cycle is short. In addition, straight-run diesel can be processed by hydrocracking, with hydrogen consumption of 2.5%, naphtha yield of 50%-60%, and liquefied gas yield of 4%-5%. In recent years, domestic refineries have also used conventional catalytic cracking units to blend straight-run diesel to reduce the diesel to gasoline ratio. For example, Sinopec Hainan Refining and Chemical Co., Ltd. blended straight-run diesel from Changsanlian into a conventional catalytic cracking unit, with a gasoline yield of 41%, but the volume fraction of propylene in liquefied gas decreased by 0.52 percentage points, and the volume fraction of isobutene decreased by 0.12 percentage points, which is not conducive to the production of low-carbon olefins.

[0004] The technology of catalytic cracking or catalytic cracking of straight-run diesel has made slow progress. On the one hand, straight-run diesel has a high value as a high-cetane-number vehicle fuel and is in short supply due to its high demand. On the other hand, the yield of straight-run diesel catalytic cracking to produce gasoline or ethylene, propylene and other chemical materials is low. In addition, the straight-run diesel catalytic cracking produces less coke, which is not enough to maintain the self-heating balance of the conventional fluidized bed catalytic cracking, and catalytic cracking also requires a higher temperature.

[0005] The existing researches at home and abroad mainly focus on improving the conversion rate and making up the heat balance. Patent CN111607425A discloses a straight-run diesel cracking method, i.e., the straight-run diesel oil from which basic nitrogen is removed by phosphoric bishydronate and inert gases such as nitrogen are introduced into a fixed bed or moving bed reactor containing activated pretreated ZSM-5 type nanomolecular sieve for catalytic cracking. Patent CN111718751A discloses a preparation method of ZSM-5 type nanomolecular sieve catalyst modified by transition metal. As described in the two patents, the straight-run diesel oil is heated to a reaction temperature as high as 600 DEG C in a fixed bed reactor, and the diesel oil conversion rate is as high as 80.16%, and the low-carbon olefin yield is 34.13%; however, the single-pass cycle is as short as 47 hours, and the reaction cycle is short, so the reactor needs to be frequently switched, and the single-pass cycle is extended to 78 hours when a moving bed reactor is used, but the operation is difficult.

[0006] Patents CN104418685B and CN104418686A both disclose a catalytic cracking method of straight-run diesel oil in a riser reactor, in which methane is used as a diluent, and the spent catalyst is exchanged with flue gas. Patent CN104418686A also discloses a cracking gasoline aromatic extraction and C2-C4 alkane steam cracking technology. As described in the two patents, the mature fluidized bed technology can realize continuous reaction-regeneration, and the heat balance problem is solved by setting a spent catalyst and flue gas heat exchanger. At a reaction temperature as high as 630 DEG C and a catalyst / oil mass ratio of 18, the diesel oil conversion rate is as high as 83.83% by carbon four recycling, and the ethylene and propylene yields are 16.52% and 35.19%, respectively; however, the spent catalyst and flue gas heat exchanger need to be added, the process is complex, the equipment investment is high, the heat exchange efficiency is low, and the flue gas contains a certain amount of oxygen, and the spent catalyst combustion is not sufficient, which is prone to hidden dangers such as tail combustion.

[0007] Therefore, in order to meet the increasing demand for low-carbon olefins and high-octane clean gasoline and solve the outlet of excess diesel oil, it is necessary to develop a production method for converting diesel oil into gasoline and liquefied gas. SUMMARY

[0008] The purpose of the present application is to provide a method for producing gasoline by catalytic cracking of hydrocarbons and a reaction system thereof, which has a high diesel oil conversion rate and can realize self-heat balance.

[0009] The first aspect of the present application provides a method for producing high-octane gasoline by catalytic cracking of hydrocarbons, which comprises:

[0010] (1) catalytically cracking a light hydrocarbon raw oil in the presence of a catalyst in an isokinetic fluidized bed reactor to obtain a first mixture containing a first spent catalyst and a first oil gas;

[0011] (2) separating the first mixture in a cyclone separator, and separating the oil gas into an oil gas separation system to obtain high-octane gasoline;

[0012] (3) the separated spent catalyst is introduced into a regenerator for oxygen-containing regeneration, and the regenerated catalyst is recycled back to the isokinetic fluidized bed reactor, wherein part or all of the flue gas after regeneration is recycled back to the regenerator;

[0013] The catalyst comprises at least a mesoporous molecular sieve with a ten-membered ring structure and an average pore size of 0.5-0.6 nm, and the mesoporous molecular sieve accounts for 5-10% by weight of the total catalyst.

[0014] According to the method of the first aspect of the application, in the isokinetic fluidized bed reactor, the reaction temperature is 500-560°C, the reaction pressure is 0.1-0.3 MPa, the weight ratio of catalyst to raw oil is 5-8:1, and the reaction time is 2.0-7.0 seconds.

[0015] According to the method of the first aspect of the application, the reaction section of the isokinetic fluidized bed reactor is a variable diameter with a gradually increasing diameter from bottom to top.

[0016] Preferably, in the isokinetic fluidized bed reactor, the oil gas linear velocity is 1.0-2.0 m / s, and the catalyst circulation rate is 150-200 kg / (m 2 ·s).

[0017] According to the method of the first aspect of the application, the oxygen-containing regeneration atmosphere is an oxygen-rich and / or pure oxygen atmosphere.

[0018] The temperature of the regenerator is 580-680°C, and the pressure is 0.2-0.6 MPa; and / or

[0019] The flue gas temperature recycled back to the regenerator is 380-530°C.

[0020] According to the method of the first aspect of the application, the catalyst comprises a mesoporous zeolite and a macroporous zeolite, and an inorganic oxide and optionally a clay, wherein the macroporous zeolite is a twelve-membered ring structure molecular sieve with an average pore size of 0.74 nm, and the total silica-alumina ratio of the macroporous zeolite is higher than 5.0, and the macroporous zeolite accounts for 20-50% by weight of the total catalyst.

[0021] Preferably, the average particle size of the catalyst is 40-150 microns.

[0022] More preferably, the catalyst is modified with an oxide of one or several metals and / or non-metals selected from the group consisting of IA, IIA, VA, VIA, VIIA, IB, IIB or transition metals, said oxide being in an amount of 0.5-5.0 wt% of the total catalyst.

[0023] According to the method of the first aspect of the present application, the light hydrocarbon oil feedstock is diesel oil.

[0024] Preferably, the diesel oil includes straight-run diesel oil, catalytically cracked diesel oil and / or hydrodiesel oil; the diesel oil has a boiling point of 180-380°C and a density of no more than 900 kg / m 3 .

[0025] According to the method of the first aspect of the present application, the light hydrocarbon oil feedstock is preheated before entering the reactor, and the preheating temperature is 120-300°C, preferably 160-260°C; and / or

[0026] The fluidizing medium of the isokinetic fluidized bed reactor is steam, and preferably, the mass ratio of the steam to the oil feedstock is 0.04-0.08.

[0027] According to the method of the first aspect of the present application, the method further comprises feeding heavy oil into the isokinetic fluidized bed reactor, and the feeding position of the heavy oil is above the feeding position of the light hydrocarbon oil feedstock.

[0028] The heavy oil is wax oil, residual oil and / or oil slurry separated by the oil-gas separation system in step (2).

[0029] According to the method of the first aspect of the present application, the method further comprises subjecting the heavy oil and / or the oil slurry separated by the oil-gas separation system to a second catalytic cracking reaction in a second reactor to obtain a second mixture comprising second oil gas and second spent catalyst.

[0030] The second mixture is separated in a cyclone separator.

[0031] Preferably, the second reactor is a riser reactor or a variable-diameter riser reactor.

[0032] The second aspect of the present application provides a reaction system for catalytically cracking to produce high-octane gasoline, which comprises:

[0033] The isokinetic fluidized bed reaction system comprises:

[0034] - an isokinetic fluidized bed reactor,

[0035] - a cyclone separator, and

[0036] - a stripper.

[0037] wherein the cyclone separator is arranged at the top of the isokinetic fluidized bed reactor and is in communication with the stripper, so that the spent catalyst separated by the cyclone separator is stripped in the stripper;

[0038] a regenerator,

[0039] wherein the stripper is in communication with the regenerator, so that the spent catalyst stripped by the stripper is regenerated in the regenerator; the regenerator is also in communication with the isokinetic fluidized bed reactor, so that the regenerated catalyst regenerated by the regenerator is recycled back to the isokinetic fluidized bed reactor; the regenerator further comprises a flue gas circulation system, and part or all of the flue gas after regeneration is recycled back to the regenerator;

[0040] an oil-gas separation system, which is in communication with the oil-gas outlet of the isokinetic fluidized bed reactor;

[0041] Preferably, the isokinetic fluidized bed reactor is provided with a light hydrocarbon raw oil inlet and a heavy oil inlet, and the heavy oil inlet is arranged above the light hydrocarbon raw oil inlet.

[0042] More preferably, the heavy oil inlet is in communication with the oil slurry outlet of the oil-gas separation system.

[0043] According to the reaction system of the second aspect of the present application, the reaction system further comprises a second reactor, which is a heavy oil catalytic cracking reactor, and the outlet of the second reactor is connected to the outlet section of the isokinetic fluidized bed reactor, and the second mixture comprising the second oil gas and the second spent catalyst obtained after the second catalytic cracking reaction in the second reactor is separated in a cyclone separator;

[0044] Preferably, the second reactor is a riser reactor or a variable-diameter riser reactor.

[0045] More preferably, the inlet of the second reactor is in communication with the oil slurry outlet of the oil-gas separation system.

[0046] Compared with the prior art, the present application has the following technical effects:

[0047] (1) The isokinetic fluidized bed reactor can produce continuously without external heating, compared with fixed bed and moving bed reactors; compared with conventional riser reactors, the oil agent is fully contacted, the diesel conversion rate is high, and the dry gas and coke yield are low, which is more suitable for catalytic cracking of light hydrocarbons.

[0048] (2) Regeneration in an oxygen-rich and / or pure oxygen atmosphere, compared with conventional air regeneration, the air heating heat is less, the charring intensity is high, and the regeneration temperature is also high, which can maintain a relatively high regenerated catalyst temperature.

[0049] (3) The high-temperature flue gas after regeneration is partially or totally returned to the regenerator, not only making full use of oxygen in the flue gas, but also solving the problem of heat carried out of the reaction and regeneration system by the flue gas and reducing the emission of waste gas such as carbon dioxide, thus achieving significant energy saving and emission reduction. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 The process flow diagram of one embodiment of the present application is used to explain the linear velocity fluidized bed catalytic cracking process of light hydrocarbon raw oil.

[0051] Figure 2 The process flow diagram of one embodiment of the present application is used to explain the linear velocity fluidized bed catalytic cracking process of light hydrocarbon raw oil.

[0052] REFERENCE SIGNS:

[0053] I, pre-lifting section of the reactor; II, reaction section of the reactor; III, outlet section of the reactor; IV, settler; IV-1, cyclone separator; IV-2, catalyst settling section; 1, linear velocity fluidized bed reactor; 2, light hydrocarbon raw oil; 3, atomized steam; 4, fluidizing medium I; 5, oil gas pipeline; 6, oil gas separation system; 7, dry gas; 8, liquefied gas; 9, gasoline; 10, cycle oil; 11, oil slurry; 12, heavy raw oil; 13, atomized steam; 14, stripping medium; 15, spent catalyst conveying pipeline; 16, regenerator; 17, oxygen-containing regenerated gas; 18, regenerated catalyst conveying pipeline I; 19, flue gas; 20, flue gas circulation system; 21, riser reactor; 22, fluidizing medium II; 23, regenerated catalyst conveying pipeline II. DETAILED DESCRIPTION

[0054] The present application will be further described in details by the accompanying drawings and examples. The features and advantages of the present application will become more apparent through these descriptions.

[0055] The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. Unless specifically stated otherwise, the drawings are not drawn to scale.

[0056] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0057] Before the technical solutions of the present application are described, the terms used herein are defined as follows:

[0058] The term "BTX" refers to: light aromatic hydrocarbons, benzene, toluene, xylene mixture.

[0059] The application provides a method for producing high-octane gasoline by catalytic cracking of hydrocarbon, comprising:

[0060] (1) performing catalytic cracking on a light hydrocarbon raw oil in the presence of a catalyst in an isokinetic fluidized bed reactor to obtain a first mixture comprising a first spent catalyst and a first oil gas;

[0061] (2) separating the first mixture in a cyclone separator, and separating the oil gas into an oil gas separation system for product separation to obtain high-octane gasoline;

[0062] (3) the separated spent catalyst is introduced into a regenerator for oxygen-containing regeneration, and the regenerated catalyst is recycled back to the isokinetic fluidized bed reactor, wherein part or all of the flue gas after regeneration is recycled back to the regenerator;

[0063] The catalyst comprises at least a mesoporous molecular sieve with a ten-membered ring structure and an average pore size of 0.5-0.6 nm, and the content of the catalyst in the total catalyst is 5-10 wt%.

[0064] The isokinetic fluidized bed reactor refers to that the oil gas in the catalytic cracking reaction maintains a relatively uniform linear velocity in the fluidized bed reactor. Since the catalytic cracking reaction is a rapid volume expansion reaction, the reaction section of the isokinetic fluidized bed reactor has a variable diameter that gradually increases from bottom to top. Preferably, in the isokinetic fluidized bed reactor, the linear velocity of the oil gas is 1.0-2.0 m / s, and the catalyst circulation rate is 150-200 kg / (m 2 ·s). Compared with the ordinary fluidized bed with a uniform diameter, the oil gas in the isokinetic fluidized bed reactor contacts the catalyst in a uniform linear velocity and in a plug flow state, the catalyst has a high density, and the oil gas is more fully contacted.

[0065] The application uses the isokinetic fluidized bed reactor to perform catalytic cracking on the light hydrocarbon raw oil to produce high-octane gasoline. Compared with the fixed bed and moving bed reactors, the isokinetic fluidized bed reactor can continuously produce without external heating. Compared with the conventional riser reactor, the oil agent is fully contacted, the diesel conversion rate is high, and the dry gas and coke yield are low, which is more suitable for catalytic cracking of light hydrocarbons.

[0066] Part and / or all of the high-temperature flue gas after regeneration is returned to the regenerator, which not only fully utilizes the oxygen in the flue gas, but also maintains a high regeneration temperature and a high regenerated catalyst temperature in the regenerator. This not only solves the problem that the flue gas takes heat out of the reaction and regeneration system, but also reduces the emission of waste gas such as carbon dioxide, thereby achieving significant energy saving and emission reduction.

[0067] The reaction oil gas is separated in the separation system to obtain products such as dry gas, liquefied gas and gasoline, and products containing naphthalene aromatic oil.

[0068] The reactor and the regenerator can be arranged in parallel or in overlap, and the fluidized bed and the settler can be built-in or built-out; air and / or steam and other media are used to lift the catalyst to circulate between the reactor and the regenerator.

[0069] In one embodiment, in the isokinetic fluidized bed reactor, the reaction temperature is 500-560℃, the reaction pressure is 0.1-0.3MPa, the weight ratio of catalyst to raw oil is 5-8:1, and the reaction time is 2.0-7.0 seconds.

[0070] The catalyst in the reactor can flow upward or downward; preferably, the catalyst flows upward.

[0071] In one embodiment, the reaction section of the isokinetic fluidized bed reactor is a variable diameter section with the diameter gradually increasing from bottom to top;

[0072] Preferably, in the isokinetic fluidized bed reactor, the oil gas linear velocity is 1.0-2.0m / s, and the catalyst circulation rate is 150-200kg / (m 2 ·s).

[0073] In one embodiment, the oxygen-containing regeneration atmosphere is an oxygen-rich and / or pure oxygen atmosphere;

[0074] The temperature of the regenerator is 580-680℃, and the pressure is 0.2-0.6MPa; and / or

[0075] The flue gas temperature circulating back to the regenerator is 380-530℃.

[0076] The present application uses oxygen-rich and / or pure oxygen atmosphere regeneration, which has less air heating heat, high charring intensity, high regeneration temperature, and can maintain a high regeneration agent temperature, thereby ensuring the regeneration efficiency.

[0077] In one embodiment, the catalyst comprises mesoporous zeolite and macroporous zeolite, inorganic oxide, and optionally clay, wherein the macroporous zeolite is a 12-membered ring structure molecular sieve with an average pore size of 0.74nm, and the total silica-alumina ratio of the macroporous zeolite is higher than 5.0, and the macroporous zeolite accounts for 20-50wt% of the total catalyst;

[0078] Preferably, the average particle size of the catalyst is 40-150μm;

[0079] More preferably, the catalyst is modified by using one or more metal and / or non-metal oxides selected from Group IA, Group IIA, Group VA, Group VIA, Group VIIA, Group IB, Group IIB, or transition metal elements, and the oxides account for 0.5-5.0wt% of the total catalyst.

[0080] In one embodiment, the catalyst comprises 20-50 wt% of the large pore zeolite, 5.0-10 wt% of the medium pore zeolite, 15-35 wt% of the inorganic oxide, 20-40 wt% of the clay, and 0.5-5.0 wt% of the metal oxide, based on the weight of the catalyst.

[0081] In one embodiment, the large pore zeolite is selected from one or more of REY zeolite, HY zeolite, REHY zeolite, ultrastable Y zeolite, and high-silica Y zeolite, and beta zeolite, preferably high-silica ultrastable Y zeolite having a total silica-to-alumina ratio higher than 5.0; the medium pore zeolite is selected from one or more of ZSM-5 zeolite, ZSM-11 zeolite, ZSM-12 zeolite, ZSM-23 zeolite, ZSM-35 zeolite, ZSM-38 zeolite, ZSM-48 zeolite, and ZRP zeolite; the inorganic oxide is a heat-resistant inorganic oxide, preferably a binder such as silica and / or alumina; and the clay is selected from one or more of silica, kaolin, halloysite, montmorillonite, diatomite, halloysite, saponite, rectorite, sepiolite, attapulgite, hydrotalcite, and bentonite.

[0082] In one embodiment, the catalyst is a composite of USY series large pore zeolite and ZSM series medium pore zeolite, alumina, silica binder, and optionally natural porous carrier material such as clay, wherein the large pore zeolite accounts for 20-50 wt% of the total catalyst, and has a total silica-to-alumina ratio higher than 5.0, and the medium pore zeolite accounts for 5.0-10 wt% of the total catalyst.

[0083] In one embodiment, the light hydrocarbon feedstock oil is diesel oil;

[0084] Preferably, the diesel oil is selected from straight-run diesel oil, catalytically cracked diesel oil, and / or hydroprocessed diesel oil; the diesel oil has a boiling point of 180-380°C, and a density of no more than 900 kg / m 3 .

[0085] In one embodiment, the light hydrocarbon feedstock oil is preheated before entering the reactor, and the preheating temperature is 120-300°C, preferably 160-260°C; and / or

[0086] The fluidizing medium of the isokinetic fluidized bed reactor is steam, and preferably, the mass ratio of the steam to the feedstock oil is 0.04-0.08.

[0087] The feedstock preheating can be performed by heating with a heating furnace, or by heat exchange with the product to the preheating temperature.

[0088] In one embodiment, the method further comprises feeding heavy oil into the isokinetic fluidized bed reactor, and the feeding position of the heavy oil is above the feeding position of the light hydrocarbon feedstock oil.

[0089] wherein the heavy oil is wax oil, residual oil and / or oil slurry separated by the oil-gas separation system in step (2).

[0090] In one embodiment, the method further comprises: subjecting the heavy oil and / or the oil slurry separated by the oil-gas separation system to a second catalytic cracking reaction in a second reactor to obtain a second mixture comprising a second oil gas and a second spent catalyst;

[0091] subjecting the second mixture to separation in a cyclone separator;

[0092] Preferably, the second reactor is a riser reactor or a variable diameter riser reactor.

[0093] The present application also provides a reaction system for catalytic cracking to produce high octane gasoline, comprising:

[0094] an isokinetic fluidized bed reaction system, comprising:

[0095] an isokinetic fluidized bed reactor,

[0096] a cyclone separator, and

[0097] a stripper,

[0098] wherein the cyclone separator is arranged at the top of the isokinetic fluidized bed reactor and is in communication with the stripper, so that the spent catalyst separated by the cyclone separator is stripped in the stripper;

[0099] a regenerator,

[0100] wherein the stripper is in communication with the regenerator, so that the spent catalyst stripped by the stripper enters the regenerator for regeneration; the regenerator is also in communication with the isokinetic fluidized bed reactor, so that the regenerated catalyst regenerated by the regenerator is recycled back to the isokinetic fluidized bed reactor; the regenerator further comprises a flue gas circulation system, and part or all of the regenerated flue gas is recycled back to the regenerator;

[0101] an oil-gas separation system, which is in communication with the oil-gas outlet of the isokinetic fluidized bed reactor;

[0102] Preferably, the isokinetic fluidized bed reactor is provided with a light hydrocarbon raw oil inlet and a heavy oil inlet, and the heavy oil inlet is arranged above the light hydrocarbon raw oil inlet.

[0103] More preferably, the heavy oil inlet is in communication with the oil slurry outlet of the oil-gas separation system.

[0104] In one embodiment, the reaction system further comprises a second reactor, which is a heavy oil catalytic cracking reactor, and the outlet of the second reactor is connected to the outlet section of the isokinetic fluidized bed reactor; a second mixture comprising a second oil gas and a second spent catalyst obtained after a second catalytic cracking reaction in the second reactor is separated in a cyclone separator;

[0105] Preferably, the second reactor is a riser reactor or a variable-diameter riser reactor.

[0106] More preferably, the inlet of the second reactor is in communication with the oil slurry outlet of the oil gas separation system.

[0107] In one embodiment, the reaction section of the isokinetic fluidized bed reactor is a variable-diameter section with a diameter gradually increasing from bottom to top.

[0108] In one specific embodiment of the present application, as shown in Figure 1 In this embodiment, an upward variable-diameter isokinetic fluidized bed reactor 1 is used, and the light hydrocarbon raw material oil 2 is fed into the reactor from the bottom to contact the regenerant for catalytic cracking reaction; the spent catalyst after the reaction is separated from the oil gas and then regenerated, and part of the flue gas after regeneration is recycled back to the regenerator 16. The process flow is as follows:

[0109] The light hydrocarbon raw material oil 2 is atomized by the atomizing steam 3 and introduced into the variable-diameter reaction section II at the bottom of the isokinetic fluidized bed reactor 1, and the hot regenerant is introduced into the pre-lifting section I of the fluidized bed reactor through the regenerant conveying pipeline I 18, and then flows upward into the reaction section II of the reactor under the fluidization of the fluidization medium I 4, and the light hydrocarbon raw material oil 2 contacts the hot regenerant for catalytic cracking reaction; after the reaction, the oil gas and the catalyst are separated in the cyclone separator IV-1 through the outlet section III of the reactor, and the separated catalyst is settled in the stripping section IV-2 of the reactor, and then is stripped by the stripping medium 14 and introduced into the regenerator 16 through the spent catalyst conveying pipeline 15; the spent catalyst is regenerated in the oxygen-containing atmosphere in the regenerator 16, and the oxygen-containing regeneration gas 17 includes air, oxygen, etc., and the regeneration temperature is 580-680℃, and the regenerated catalyst is recycled; part of the flue gas 19 after regeneration is recycled back to the regenerator 16 through the flue gas circulation system 20; the separated reaction oil gas is introduced into the oil gas separation system 6 through the reaction oil gas pipeline 5, and the products dry gas 7, liquefied gas 8, gasoline 9, cycle oil 10 and oil slurry 11 are obtained by separation, wherein the cycle oil 10 and the oil slurry 11 can be selected to be recycled and / or not recycled according to production needs. In order to meet the need of self-heat balance of the device, the oil slurry recycling is preferred; the oil slurry recycling and / or the heavy raw material oil 12 are atomized by the atomizing steam 13 and then introduced into the reactor, preferably into the middle part of the reaction section II of the variable-diameter isokinetic fluidized bed reactor, i.e. above the light hydrocarbon raw material oil nozzle.

[0110] Figure 2The process flow diagram of another embodiment of the present application is shown in Figure 2, which is the same as that of Figure 1, except that the oil slurry is recycled and / or the heavy feed oil 12 is introduced into a conventional riser reactor. The conventional riser and the light hydrocarbon fluidized bed reactor can each have a separate settler or share one settler. In this embodiment, they share one settler.

[0111] The light hydrocarbon feed oil 2 is atomized by steam 3 and introduced into the bottom of the variable-diameter reactor section II of the isokinetic fluidized bed reactor 1, and the hot regenerated catalyst is introduced into the pre-lifting section I of the isokinetic fluidized bed reactor 1 through the regenerated catalyst conveying pipeline 18, and then flows upward into the reaction section II under the fluidization of the fluidization medium I 4, and the light hydrocarbon feed oil 2 is contacted with the hot regenerated catalyst to perform catalytic cracking reaction. The heavy feed oil 12 is atomized by steam 13 and introduced into the lower part of the riser reactor 21, and the hot regenerated catalyst is introduced into the bottom of the riser reactor 21 through the regenerated catalyst conveying pipeline II 23, and then flows upward under the fluidization of the fluidization medium II 22, and the heavy feed oil 12 is contacted with the hot regenerated catalyst to perform catalytic cracking reaction. The oil gas after the catalytic cracking of the light hydrocarbon feed oil 2 and the heavy feed oil 12 is introduced into the cyclone separator IV-1 to separate the catalyst. The separated catalyst is settled into the stripping section IV-2 of the reactor, and then is stripped by the stripping medium 14 and introduced into the regenerator 16 through the spent catalyst conveying pipeline 15. The spent catalyst is regenerated in the oxygen-containing atmosphere in the regenerator 16, and the oxygen-containing regeneration gas 17 includes air, oxygen, etc. The regeneration temperature is 500-800°C. The regenerated catalyst is recycled. Part of the flue gas 19 after the regeneration is recycled back to the regenerator 16 through the flue gas circulation system 20. The separated oil gas is introduced into the oil gas separation system 6 through the oil gas pipeline 5, and then is separated to obtain dry gas 7, liquefied gas 8, gasoline 9, cycle oil 10 and oil slurry 11. The cycle oil 10 and the oil slurry 11 can be recycled and / or not recycled according to the production needs. The oil slurry 11 can be recycled into the middle part of the variable-diameter reactor section II of the isokinetic fluidized bed reactor 1, and the heavy feed oil 12 is atomized by steam 13 and introduced into the riser reactor 21 to perform catalytic cracking reaction.

[0112] The present application is further illustrated in detail by the following examples. The raw materials used in the examples can be obtained by commercial purchase.

[0113] The following examples will further illustrate the present method, but do not limit the present method.

[0114] The light hydrocarbon feed used in the examples is a certain refinery straight-run diesel and catalytic cracking diesel, which is hydrogenated at a mass ratio of 4:1 to produce hydrogenated diesel. The heavy feed oil is a certain refinery residue hydrogenated to produce hydrogenated residue. The properties of the two are shown in Table 1.

[0115] The catalyst used in the example is the same, and its preparation method is briefly described as follows:

[0116] 1) 10 kg of NH4CI was dissolved in 500 kg of water, 50 kg (dry basis) of crystalline product DASY zeolite (produced by SINOPEC Catalyst Qilu Branch, cell constant 2.445-2.455 nm, rare earth content RE2O3 = 8.0 wt%) was added to the solution, and after 0.5 h of exchange at 90 °C, a filter cake was obtained by filtration; 1.1 kg of Fe(NO3)3-9H2O dissolved in 3.3 kg of water was added to the filter cake for impregnation and drying; then, a large pore zeolite containing iron was obtained by calcination at 550 °C for 2 h, and the elemental analysis chemical composition was 0.1 Na2O-5.1 Al2O3-1.0 Fe2O3-7.6 RE2O3-88.1 SiO2.

[0117] 2) 18.8 kg of hydrous kaolin (Suzhou Kaolin Industrial Product, solid content 71.6 wt%) was slurried with 125 kg of de-cationic water, and then 13.7 kg of pseudo-boehmite (Shandong Aluminum Industrial Product, solid content 63 wt%) was added, and the pH was adjusted to 2-4 with hydrochloric acid, and the mixture was stirred uniformly and aged at 60-70 °C for 1 h while maintaining the pH at 2-4, and then the temperature was reduced to below 60 °C, and 10.4 kg of aluminum sol (SINOPEC Catalyst Qilu Branch Product, Al2O3 content 21.7 wt%) was added, and the mixture was stirred for 40 min to obtain a mixed slurry.

[0118] 3) The large pore zeolite containing iron prepared in step 1) (8.5 kg dry basis) and MFI structure mesoporous ZRP-1 zeolite (SINOPEC Catalyst Qilu Branch Industrial Product, SiO2 / Al2O3 = 30, phosphorus content P2O5 = 3.5 wt%, 2.1 kg dry basis) were added to the mixed slurry obtained in step 2), and the mixture was stirred uniformly, placed in a binder, and an appropriate amount of water was added, and the mixture was stirred uniformly, and was placed in air for 4 h, and was spray dried, and was dried in a drying oven at 120 °C for 3 h, and then was washed with ammonium dihydrogen phosphate solution (phosphorus content 1 wt%) to remove free Na + , and then was dried again at 120 °C for 3 h to obtain a catalyst, which is denoted as CAT-1. The composition of the catalyst was 24.0 wt% DASY zeolite, 0.3 wt% iron oxide, 6.0 wt% MFI structure mesoporous zeolite, 24.7 wt% pseudo-boehmite, 6.5 wt% aluminum sol, and 38.5 wt% kaolin. The properties are listed in Table 2.

[0119] Example 1

[0120] This example was carried out according to the method of Example 1, except that the catalyst used was CAT-2. Figure 1The process was tested using hydrogenated diesel A in Table 1 as the raw material, and a CAT-1 catalyst was used in the test in an isokinetic fluidized bed reactor. The raw material oil A was preheated to 260°C and then entered the bottom of the reaction section of the isokinetic fluidized bed reactor. The water vapor was used as the fluidizing medium, the mass ratio of the atomized steam to the raw material oil was 0.05, and the fluidizing medium flowed upward. The catalytic cracking reaction was carried out under the conditions of a reaction temperature (at the outlet of the reactor) of 540°C, a weight ratio of the catalyst to the raw material oil of 8.0, and a reaction time of 3.0 seconds at a reaction pressure of 0.24 MPa. After the reaction, oil agent separation was carried out, and the separated reaction oil gas was subjected to product separation in a separation system to obtain dry gas, liquefied gas, gasoline, cycle oil, and oil slurry, etc. The oil slurry was partially recycled. The spent catalyst after the oil agent separation was subjected to steam stripping to remove the oil gas adsorbed in the catalyst, and then was sent to a regenerator. Oxygen was used as the regeneration gas, and the regenerated catalyst was contacted with the spent catalyst at a regeneration temperature of 580-680°C. The regenerated catalyst was recycled, and part of the flue gas after the regeneration was recycled. The temperature of the recycled flue gas was 400°C, and the dense phase temperature of the regeneration was maintained at 608°C. The operating conditions and product distribution are listed in Table 3.

[0121] As can be seen from Table 3, in Example 1, the hydrogenated diesel was subjected to catalytic cracking reaction in the isokinetic fluidized bed reactor. The liquefied gas yield was 25.95 wt%, the gasoline yield was 53.83 wt%, the low-carbon olefin (ethylene + propylene + butene) yield was 12.32 wt%, the BTX (benzene + toluene + xylene) yield was 11.15 wt%, and the gasoline octane number RON reached 95.7.

[0122] Comparative Example 1

[0123] The catalytic cracking reaction was carried out by using the same raw material oil and catalyst as in Example 1 and under the same process conditions, except that: 1) a riser reactor was used in Comparative Example 1; 2) air was used as the regeneration gas, and the flue gas was not recycled; and 3) in order to maintain the same process conditions as in Example 1, combustion oil was needed to be sprayed in the regenerator to provide heat. The operating conditions and product distribution are listed in Table 3.

[0124] As can be seen from Table 3, compared with Comparative Example 1 (the riser reactor), the gasoline yield in Example 1 (the isokinetic fluidized bed reactor) was higher, which was 2.60 percentage points higher than that in Comparative Example 1; the low-carbon olefin yield was higher, which was 1.05 percentage points higher than that in Comparative Example 1; and the gasoline octane number was slightly increased, which was 0.4 units higher than that in Comparative Example 1.

[0125] Example 2

[0126] In this example, the process was tested using hydrogenated diesel A in Table 1 as the raw material, and a CAT-1 catalyst was used in the test in an isokinetic fluidized bed reactor. The raw material oil A was preheated to 260°C and then entered the bottom of the reaction section of the isokinetic fluidized bed reactor. The water vapor was used as the fluidizing medium, the mass ratio of the atomized steam to the raw material oil was 0.05, and the fluidizing medium flowed upward. The catalytic cracking reaction was carried out under the conditions of a reaction temperature (at the outlet of the reactor) of 540°C, a weight ratio of the catalyst to the raw material oil of 8.0, and a reaction time of 3.0 seconds at a reaction pressure of 0.24 MPa. After the reaction, oil agent separation was carried out, and the separated reaction oil gas was subjected to product separation in a separation system to obtain dry gas, liquefied gas, gasoline, cycle oil, and oil slurry, etc. The oil slurry was partially recycled. The spent catalyst after the oil agent separation was subjected to steam stripping to remove the oil gas adsorbed in the catalyst, and then was sent to a regenerator. Oxygen was used as the regeneration gas, and the regenerated catalyst was contacted with the spent catalyst at a regeneration temperature of 580-680°C. The regenerated catalyst was recycled, and part of the flue gas after the regeneration was recycled. The temperature of the recycled flue gas was 400°C, and the dense phase temperature of the regeneration was maintained at 608°C. The operating conditions and product distribution are listed in Table 3. Figure 2The process was tested using the hydrogenated diesel A and hydrogenated residual oil B in Table 1 as raw materials, which were respectively tested in the isokinetic fluidized bed reactor and the riser reactor, and CAT-1 catalyst was used. The raw material oil A was preheated to 200°C and then entered the isokinetic fluidized bed reactor at the bottom of the reaction section, and the raw material oil B was preheated to 200°C and then entered the conventional riser reactor at the bottom; both were under the reaction pressure of 0.22 MPa, water vapor was used as the fluidizing medium, the mass ratio of atomized steam to raw material oil was 0.05, and the catalytic cracking reaction was carried out under the conditions that the reaction temperature (measured at the outlet of the reactor) was 520°C, the weight ratio of catalyst to raw material oil was 6.0, and the reaction time was 7.0 seconds; the oil gas and catalyst after the reaction of the raw material oil B in the riser reactor were merged into the isokinetic fluidized bed reactor, and the oil gas after the reaction of the raw material oil A was separated from the catalyst; the reaction oil gas after the oil catalyst separation was subjected to product separation through the separation system to obtain dry gas, liquefied gas, gasoline, cycle oil and oil slurry and other products, and part of the oil slurry was recycled; the spent catalyst after the oil catalyst separation was subjected to steam stripping to remove the oil gas adsorbed inside, and then was sent to the regenerator, and the oxygen-rich air with 20% oxygen and 80% air was used as the regeneration gas to contact with the spent catalyst at the regeneration temperature of 580-680°C to regenerate; the regenerated catalyst was recycled, and part of the flue gas after the regeneration was recycled, the circulating flue gas temperature was 500°C, and the dense phase temperature of the regeneration was maintained at 664°C. The operating conditions and product distribution are listed in Table 3.

[0127] As can be seen from Table 3, in Example 2, the hydrogenated diesel oil was subjected to catalytic cracking in the isokinetic fluidized bed reactor, and the hydrogenated residual oil was subjected to catalytic cracking in the riser reactor, the liquefied gas yield was 18.98 wt%, the gasoline yield was 57.86 wt%, the low-carbon olefin (ethylene + propylene + butene) yield was 8.94 wt%, the BTX (benzene + toluene + xylene) yield was 9.98 wt%, and the gasoline octane number RON reached 94.1.

[0128] Comparative Example 2

[0129] The catalytic cracking reaction was carried out by using the same raw material oil and catalyst as in Example 2 and under the same process conditions, except that: 1) in Comparative Example 2, both the hydrogenated diesel oil A and the hydrogenated residual oil B were subjected to catalytic cracking in the riser reactor; 2) air was used as the regeneration gas, and the flue gas was not recycled; 3) in order to maintain the same process conditions as in Example 2, it was necessary to provide heat by spraying combustion oil in the regenerator. The operating conditions and product distribution are listed in Table 3.

[0130] As can be seen from Table 3, compared with Example 2 (isokinetic fluidized bed reactor) and Comparative Example 2 (riser reactor), the gasoline yield was higher, which was 1.08 percentage points higher than that of Comparative Example 2; the liquefied gas and low-carbon olefin yields were higher, which were 1.33 and 0.53 percentage points higher than those of Comparative Example 2, respectively; and the gasoline octane number increased slightly, which was 0.3 units higher than that of Comparative Example 2.

[0131] The application has been described above with reference to preferred embodiments. However, these embodiments are merely exemplary and are intended to be illustrative only. Various substitutions and alterations to the application can be made by those of ordinary skill in the art without departing from the scope of the application.

[0132] Table 1

[0133] Feedstock oil name Hydrogenated diesel Heavy feedstock oil Feedstock oil number A B 20°C density, kg / m3 3 ]] 844.0 929.6 Sulfur content, wt% 0.0009 0.22 Nitrogen content, wt% 0.0001 0.21 Four components Saturated hydrocarbons, wt% 81.8 56.9 Aromatic hydrocarbons, wt% 18.2 29.8 Gum, wt% - 12.7 Asphaltene, wt% - 0.6 ASTM D86 distillation range, °C Initial boiling point 220 283.3 10％ 248 371.3 50％ 303 517.2 90％ 361 - Final boiling point 373 -

[0134] Table 2

[0135]

[0136]

[0137] Table 3

[0138]

[0139]

Claims

1. A process for the production of high octane gasoline from hydrocarbons catalytically cracked, characterized in that, The method comprises: (1) in an isokinetic fluidized bed reactor, a light hydrocarbon raw oil is catalytically cracked in the presence of a catalyst to obtain a first mixture comprising a first spent catalyst and a first oil gas; (2) the first mixture is separated in a cyclone separator, and the separated oil gas enters an oil gas separation system for product separation to obtain high-octane gasoline; (3) the separated spent catalyst enters a regenerator for oxygen-containing regeneration, and the regenerated catalyst is recycled back to the isokinetic fluidized bed reactor, wherein part or all of the flue gas after regeneration is recycled back to the regenerator, and the oxygen-containing regeneration atmosphere is an oxygen-rich and / or pure oxygen atmosphere; The catalyst comprises at least a mesoporous molecular sieve with a ten-membered ring structure having an average pore size of 0.5-0.6 nm, and the content of the mesoporous molecular sieve in the total catalyst is 5-10 wt%.

2. The method of claim 1, wherein, In the isokinetic fluidized bed reactor, the reaction temperature is 500-560°C, the reaction pressure is 0.1-0.3 MPa, the weight ratio of catalyst to raw oil is 5-8:1, and the reaction time is 2.0-7.0 seconds.

3. The method of claim 1, wherein, The reaction section of the isokinetic fluidized bed reactor is a variable diameter with a diameter gradually increasing from bottom to top.

4. The method of claim 3, wherein, In the isokinetic fluidized bed reactor, the oil gas linear velocity is 1.0-2.0 m / s, and the catalyst circulation rate is 150-200 kg / (m 2 ·s).

5. The method of claim 1, wherein The temperature of the regenerator is 580-680°C, and the pressure is 0.2-0.6 MPa; and / or The temperature of the flue gas recycled to the regenerator is 380-530°C.

6. The method of claim 1, wherein, The catalyst comprises a mesoporous zeolite and a macroporous zeolite, wherein the macroporous zeolite is a twelve-membered ring structure molecular sieve with an average pore size of 0.74 nm, and the total silica-alumina ratio of the macroporous zeolite is higher than 5.0, and the content of the macroporous zeolite in the total catalyst is 20-50 wt%.

7. The method of claim 6, wherein, The average particle size of the catalyst is 40-150 microns.

8. The method of claim 7, wherein, The catalyst is modified by using an oxide of one or more metals and / or non-metals selected from group IA, group IIA, group VA, group VIA, group VIIA, group IB, group IIB or transition metals, and the content of the oxide in the total catalyst is 0.1-5.0 wt%.

9. The method of claim 1, wherein, The light hydrocarbon raw oil is diesel oil.

10. The method of claim 9, wherein, The diesel oil includes straight-run diesel oil, catalytically cracked diesel oil and / or hydrogenated diesel oil; the diesel oil has a boiling point of 180-380℃ and a density of not more than 900 kg / m 3 .

11. The method of claim 1, wherein, The light hydrocarbon raw oil is preheated before entering the reactor, and the preheating temperature is 120-300°C; and / or The fluidizing medium of the isokinetic fluidized bed reactor is steam.

12. The method of claim 11, wherein, The preheating temperature is 160-260°C; and / or The mass ratio of steam to raw oil is 0.04-0.

08.

13. The method of claim 1, wherein, The method further comprises feeding heavy oil into the isokinetic fluidized bed reactor, and the feeding position of the heavy oil is above the feeding position of the light hydrocarbon raw oil. The heavy oil is wax oil or residual oil; and / or the oil slurry separated by the oil gas separation system in step (2).

14. The method of claim 1, wherein, The method further comprises: performing a second catalytic cracking reaction on the heavy oil and / or the oil slurry separated by the oil gas separation system in a second reactor to obtain a second mixture comprising a second oil gas and a second spent catalyst; The second mixture is separated in a cyclone separator.

15. The method of claim 14, wherein, The second reactor is a riser reactor or a variable-diameter riser reactor.

16. A reaction system for the catalytic cracking production of high octane gasoline for carrying out the process according to any one of claims 1 to 15, characterized in that, The reaction system comprises: The isokinetic fluidized bed reaction system comprises: an isokinetic fluidized bed reactor, - a cyclone separator, and - a stripper, wherein the cyclone separator is disposed at the top of the isokinetic fluidized bed reactor and is in communication with the stripper, such that the spent catalyst separated by the cyclone separator is stripped in the stripper; a regenerator, wherein the stripper is in communication with the regenerator, such that the spent catalyst stripped by the stripper is regenerated in the regenerator; the regenerator is also in communication with the isokinetic fluidized bed reactor, such that the regenerated catalyst regenerated by the regenerator is recycled back to the isokinetic fluidized bed reactor; the regenerator further comprises a flue gas circulation system, and part or all of the flue gas after regeneration is recycled back to the regenerator; an oil-gas separation system, which is in communication with the oil-gas outlet of the isokinetic fluidized bed reactor.

17. The reaction system of claim 16, wherein, The isokinetic fluidized bed reactor is provided with a light hydrocarbon raw oil inlet and a heavy oil inlet, and the heavy oil inlet is disposed above the light hydrocarbon raw oil inlet.

18. The reaction system of claim 17, wherein, The heavy oil inlet is in communication with the oil slurry outlet of the oil-gas separation system.

19. The reaction system of claim 16, wherein, The reaction system further comprises a second reactor, which is a heavy oil catalytic cracking reactor, and the outlet of the second reactor is connected to the outlet section of the isokinetic fluidized bed reactor, and the second mixture containing second oil gas and second spent catalyst obtained after the second catalytic cracking reaction in the second reactor is separated in the cyclone separator.

20. The reaction system of claim 19, wherein, The second reactor is a riser reactor or a variable-diameter riser reactor.

21. The reaction system of claim 20, wherein, The inlet of the second reactor is in communication with the oil slurry outlet of the oil-gas separation system. The reaction system further comprises a second reactor, which is a heavy oil catalytic cracking reactor, and the outlet of the second reactor is connected to the outlet section of the isokinetic fluidized bed reactor, and the second mixture containing second oil gas and second spent catalyst obtained after the second catalytic cracking reaction in the second reactor is separated in the cyclone separator.

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