A catalytic cracking reaction method and system for heavy crude oil

Abstract

The present application relates to a catalytic cracking reaction method and system for heavy feedstock oil, which includes a catalytic cracking reactor, a coke generator, an oil agent separation device, a settling stripper, and a regenerator. The method includes: 1) subjecting the heavy feedstock oil to a catalytic cracking reaction to obtain a first reaction product and a first regenerated catalyst; 2) introducing the coke-forming feedstock into the coke generator for a coke-forming reaction to obtain a second reaction product and a second catalyst; 3) introducing the first reaction product and the second reaction product into a separation system for separation; 4) transporting the first regenerated catalyst and the second regenerated catalyst to the regenerator for charring and regeneration, and returning the resulting regenerated catalyst to the bottom of the catalytic cracking reactor and the coke generator for recycling. The catalytic cracking method and system of the present application can improve the yield of ethylene and propylene while providing a coke source for the regeneration process, thereby solving the problem of reaction heat balance, not affecting the regeneration process, and not damaging the physical and chemical properties of the catalyst.

Description

Technical Field

[0001] The present application relates to the technical field of fluidized catalytic cracking, and more specifically, to a reaction method and system suitable for catalytic cracking of heavy crude oil. Background Art

[0002] The fluidized catalytic cracking (FCC) reaction is a self-heating equilibrium process. The catalyst's regeneration process releases a large amount of high-temperature heat energy, which precisely meets the needs of the lower-temperature cracking reaction. The catalyst circulating between the reactor and regenerator has a sufficient quantity and heat capacity, so the catalyst serves as both an active site for the reaction and a heat carrier for heat transfer. As the catalyst flows between the reactor and regenerator, it continuously absorbs heat from one end and supplies it to the other. Establishing thermal equilibrium requires certain conditions to maintain the desired cracking and regeneration temperatures. For a catalytic cracking industrial unit, thermal equilibrium between the reactor and regenerator is based on sufficient coke production, which is burned during the regeneration process, releasing heat for the reaction.

[0003] Catalytic cracking processes typically utilize feedstocks with high hydrogen content, such as vacuum gas oil or atmospheric residue from paraffinic crude oils. While high-quality catalytic cracking feedstocks can yield high yields of light olefins, the resulting coke production is insufficient to meet the heat requirements of the catalytic cracking reaction, necessitating external coking feedstock. Advances in oil refining, particularly the increasing trend toward heavier and inferior crude oils and improved oil quality, have led to the widespread application of hydrogenation processes. While hydrogenation significantly improves product structure and quality when used as catalytic cracking feedstock, it also creates a coke shortage within the catalytic cracking unit itself, leading to insufficient heat supply. Furthermore, catalytic cracking technologies targeting light olefins as their primary target products often require more heat than conventional fluidized bed catalytic regenerators or other catalytic conversion methods due to the high conversion rate, high reaction temperature, and high heat of reaction. The resulting coke often fails to meet the heat balance requirements of the reaction-regeneration system. When insufficient coke is produced during the reaction, slurry oil recycling or external fuel oil addition to the regenerator is often used to provide the required heat. Because the slurry contains a large amount of polycyclic aromatic hydrocarbons, it is very easy to adsorb on the active centers of the catalyst, affecting the accessibility of the active centers of the feedstock molecules, thereby affecting the selectivity of the catalytic reaction. In addition, since the catalytic cracking uses a catalyst with a molecular sieve as the active component, the local high temperature generated by the combustion of fuel oil in the regenerator causes the molecular sieve framework aluminum to gradually be removed, resulting in damage to the catalyst. This damage is irreversible and does not fundamentally solve the impact of the high-temperature hot spots generated by the local combustion of external fuel oil on the catalyst skeleton structure and reaction performance. To solve this problem, the existing technical solutions all start from the regenerator system, such as setting up an oxygen-depleted area in the regenerator, introducing fuel oil into the oxygen-depleted area to mix with the catalyst, and then entering the regenerator for char regeneration; or arranging a heater in the regenerator and using a fuel nozzle that is configured to spray a mixture of fuel and oxygen-containing gas for combustion to supplement heat; or injecting methane and relying on the heat released by the combustion of methane to supplement heat for the reaction. The heat supplementation methods in the above technologies have alleviated the adverse effects of the catalyst to some extent, but have not fundamentally solved the impact of the high-temperature hot spots generated by the local combustion of external fuel oil on the catalyst skeleton structure and reaction performance. Summary of the Invention

[0004] The purpose of this application is to provide a catalytic cracking reaction method and system for heavy crude oil, which has high selectivity for ethylene and propylene and provides the required coke source for the regeneration process, solves the problem of heat balance in the catalytic cracking reaction process from the reaction aspect, and does not affect the physical and chemical properties of the catalyst.

[0005] In one aspect, the present application provides a catalytic cracking reaction-regeneration system, comprising:

[0006] Catalytic cracking reactor,

[0007] coke generator,

[0008] Oil separation equipment,

[0009] settling strippers, and

[0010] Regenerator,

[0011] The catalytic cracking reactor is provided with a lifting medium inlet, a regenerated catalyst inlet, a cracking feedstock oil inlet and an oil agent outlet;

[0012] The oil agent outlet of the catalytic cracking reactor is connected to the oil agent separation device, so that the oil agent of the catalytic cracking reactor enters the oil agent separation device and is separated into a first reaction product and a first spent catalyst;

[0013] The coke generator is coaxially arranged with the settling stripper, and the coke generator comprises, from bottom to top, the following components:

[0014] Pre-lift area,

[0015] a coke-forming reaction zone, wherein the coke-forming reaction zone is a bubbling fluidized bed or a turbulent fluidized bed, and

[0016] Export Zone,

[0017] wherein the top of the pre-lifting zone is connected to the coke-generating reaction zone, and the top of the coke-generating reaction zone is connected to the outlet zone;

[0018] At least one fuel oil feed port is provided in the middle and upstream of the coking reaction zone;

[0019] The outlet area of the coke generator is connected to the oil-agent separation device, so that the material of the coke generator enters the oil-agent separation device and is separated into the second reaction product and the second catalyst to be generated;

[0020] The oil separation device is accommodated inside the settling stripper, so that the first catalyst to be regenerated and the second catalyst to be regenerated separated by the oil separation device are settled in the settling stripper; and the settling stripper is connected to the regenerator, so that the first catalyst to be regenerated and the second catalyst to be regenerated in the settling stripper are transported to the regenerator;

[0021] The regenerator is provided with a first regenerated catalyst outlet and a second regenerated catalyst outlet, wherein the first regenerated catalyst outlet is connected to the regenerated catalyst inlet of the catalytic cracking reactor, so that at least a portion of the regenerated catalyst is circulated back to the catalytic cracking reactor;

[0022] The bottom end of the pre-lifting zone of the coke maker and / or the bottom end of the coke forming reaction zone is configured to communicate with the second regenerated catalyst outlet of the regenerator for conveying at least a portion of the regenerated catalyst of the regenerator to the coke maker.

[0023] In one embodiment, the coke generator is provided with the pre-lift gas inlet, the catalyst inlet and the coke raw material inlet in sequence from bottom to top.

[0024] In one embodiment, the coking raw material inlets are independently arranged in the middle and upstream of the coking device; preferably, the distance between the coking raw material inlets and the bottom of the coking device is independently 5% to 15% of the height of the coking device.

[0025] In one embodiment, the coke-generating reaction zone is a hollow cylinder with an aspect ratio of 20:1 to 2:1;

[0026] In one embodiment, the pre-lifting area is a hollow cylinder with an aspect ratio of 10:1 to 2:1;

[0027] The outlet area is a hollow cylinder with a length-to-diameter ratio of 30:1-5:1.

[0028] In one embodiment, the ratio of the inner diameters of the pre-lifting zone, the coking reaction zone, and the outlet zone is 1:2:1 to 1:10:2.

[0029] On the other hand, the present application also provides a method for catalytic cracking of heavy crude oil, the method comprising:

[0030] 1) introducing the heavy crude oil into the catalytic cracking reactor, contacting it with the regenerated catalyst from the regenerator and performing a catalytic cracking reaction to obtain a first reaction product and a first catalyst to be regenerated;

[0031] 2) The coking raw material is introduced from the bottom of the coking vessel to contact the regenerated catalyst from the regenerator and the coking reaction is carried out from bottom to top to obtain the second reaction product and the second catalyst.

[0032] 3) introducing the first reaction product and the second reaction product into a separation system for separation,

[0033] 4) The first catalyst to be regenerated and the second catalyst to be regenerated are transported to the regenerator for charring and regeneration, and the regenerated catalyst is returned to the bottom of the catalytic cracking reactor and the coking vessel for recycling.

[0034] In one embodiment, the conditions of the catalytic cracking reaction include: a reaction temperature of 510-650°C, a reaction time of 1-20 seconds, a catalyst-oil weight ratio of (3-30):1, a weight ratio of pre-lift gas to feed oil of (0.03-1.0):1, and a reaction pressure of 130-450 kPa.

[0035] In one embodiment, the conditions of the coking reaction include: the outlet temperature of the coking device is 460-560°C, the reaction time is 1-20 seconds, the catalyst-oil weight ratio is (3-30):1, the weight ratio of the pre-lift gas to the coking raw material is (0.01-0.5):1, the linear velocity is 0.2 m / s-1.2 m / s, and the catalyst particle density is 300 kg / m3-700 kg / m3.

[0036] In one embodiment, the properties of the heavy feedstock oil meet one, two, three or four of the following indicators: density at 20°C 850-920 kg / m 3 , residual carbon 0-2 weight%, characteristic factor K value greater than 12.1, saturated hydrocarbon content 60%-100 weight%; preferably, the heavy feedstock oil is selected from one or more of petroleum hydrocarbons, non-petroleum hydrocarbon mineral oils, synthetic oils, animal fats and vegetable fats.

[0037] In one embodiment, the coking raw material is the slurry oil produced by the device and the secondary processed distillate oil, or a mixture thereof; preferably, the secondary processed distillate oil can be selected from a mixture of one or more of catalytic cracking diesel, catalytic cracking diesel, catalytic cracking slurry oil, catalytic cracking slurry oil, coker gasoline, coker diesel and coker gas oil; more preferably, the coking raw material is the slurry oil produced by the device.

[0038] In one embodiment, the method is carried out in the above-mentioned catalytic cracking reaction-regeneration system of the present application.

[0039] A coking device is added to the catalytic cracking reaction system of the present application. A coking reaction occurs in the coking device, and the reaction oil generated by the cracking reactor can be allowed to enter the settler together with the reaction oil and gas generated by the coking device, which helps to reduce the temperature of the mixed oil and gas and reduce over-cracking reaction; the coking device in the catalytic cracking reaction system of the present application also generates a catalyst with coke, which can enter the regeneration system together with the catalyst with coke generated by the cracking reactor for regeneration without affecting the operation of the regeneration system. The catalyst with coke has no local hot spots during the coking process in the regenerator, and has no damage to the physical and chemical properties of the catalyst. The reaction system of the present application has a simple structure, is easy to implement, and has strong applicability. It can be applied to catalytic cracking units with insufficient coking, especially catalytic cracking units with chemical raw materials such as light olefins as the main target products. It fundamentally solves the problem of heat balance of the catalytic cracking reaction from the reaction system end, and reduces the damage to the catalyst and the regeneration system caused by the traditional method of spraying combustion oil, which not only saves catalyst costs but also improves the economic benefits of the refinery. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the following detailed description, they are used to explain the present application but do not constitute a limitation of the present application. In the accompanying drawings:

[0041] Figure 1 is a schematic diagram of a coke generator;

[0042] Figure 2 A schematic diagram of an embodiment of a heavy crude oil catalytic cracking system. DETAILED DESCRIPTION

[0043] The present application will be further described in detail below through the accompanying drawings and examples, through which the features and advantages of the present application will become more clear and distinct.

[0044] The word "exemplary" is used exclusively herein to mean "serving as an example, example, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0045] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0046] Any specific numerical value disclosed herein (including the endpoints of a numerical range) is not limited to the exact value of that value, but should be understood to also include values close to that exact value, such as all possible values within ±5% of that exact value. Moreover, for a disclosed numerical range, any combination of the endpoints of the range, between an endpoint and a specific point within the range, and between each specific point can be used to generate one or more new numerical ranges, and these new numerical ranges should also be considered to be specifically disclosed herein.

[0047] In this application, the terms "upstream" and "downstream" are used in relation to the direction of flow of the reactants. For example, when the reactants flow from bottom to top, "upstream" refers to a position below, while "downstream" refers to a position above.

[0048] Unless otherwise specified, the terms used herein have the same meaning as commonly understood by those skilled in the art. If a term is defined herein and its definition is different from the commonly understood meaning in the art, the definition herein shall prevail.

[0049] The present application provides a catalytic cracking reaction-regeneration system, which comprises:

[0050] Catalytic cracking reactor,

[0051] coke generator,

[0052] Oil separation equipment,

[0053] settling strippers, and

[0054] Regenerator.

[0055] The present application also provides a method for catalytic cracking of heavy crude oil, the method comprising:

[0056] 1) introducing the heavy crude oil into the catalytic cracking reactor, contacting it with the regenerated catalyst from the regenerator and performing a catalytic cracking reaction to obtain a first reaction product and a first catalyst to be regenerated;

[0057] 2) The coking raw material is introduced from the bottom of the coking vessel to contact the regenerated catalyst from the regenerator and the coking reaction is carried out from bottom to top to obtain the second reaction product and the second catalyst.

[0058] 3) The first reaction product and the second reaction yield are introduced into a separation system for separation to obtain dry gas, liquefied gas, pyrolysis gasoline, pyrolysis diesel, and slurry oil.

[0059] 4) The first catalyst to be regenerated and the second catalyst to be regenerated are transported to the regenerator for charring and regeneration, and the regenerated catalyst is returned to the bottom of the catalytic cracking reactor and the coking vessel for recycling.

[0060] Figure 2 The catalytic cracking reaction-regeneration system of the present application is shown. The catalytic cracking method of the present application is further described below in conjunction with the catalytic cracking reaction-regeneration system. The following description of the catalytic cracking method of the present application is also applicable to the catalytic cracking reaction-regeneration system of the present application, and vice versa.

[0061] The catalytic cracking reaction-regeneration system of the present application comprises:

[0062] Catalytic cracking reactor 100,

[0063] Coke generator 300,

[0064] Oil separation equipment 201,

[0065] Settling stripper 200, and

[0066] Regenerator 500.

[0067] like Figure 2As shown, the catalytic cracking reactor 100 is equipped with a pre-lift gas inlet 101, a cracking feedstock feed inlet 102 at the bottom, a catalyst inlet 103 at the bottom, and an oil outlet 104 at the top. In this application, the catalyst inlet 103 of the cracking reactor 100 is fluidically connected to the first regenerated catalyst outlet 508 of the regenerator 500, allowing at least a portion of the regenerated catalyst to be recycled back to the catalytic cracking reactor 100. The oil outlet 104 of the cracking reactor is fluidically connected to the oil inlet of the oil separation device 201, allowing the oil from the catalytic cracking reactor to enter the oil separation device for separation into a first reaction product and a first regenerated catalyst. After the first reaction product is collected in the gas collection chamber 202, it is introduced into a reaction product separation system (not shown) via the oil and gas pipeline 203 for separation to produce various products, such as dry gas, liquefied gas, pyrolysis gasoline, pyrolysis diesel, and slurry oil.

[0068] In the catalytic cracking system of the present application, there may be one or more catalytic cracking reactors, a combination of one catalytic cracking reactor of the present application and another existing catalytic cracking reactor, or a combination of multiple catalytic cracking reactors of the present application. These reactors may be connected in parallel and connected to the oil separation device.

[0069] The reaction product separation system may be provided with a reaction product inlet, a dry gas outlet, a liquefied gas outlet, a pyrolysis gasoline outlet, a pyrolysis diesel outlet, and a pyrolysis heavy oil outlet, and is used to separate the reaction products into components such as dry gas, liquefied gas, pyrolysis gasoline, pyrolysis diesel, and pyrolysis heavy oil according to the distillation range. The dry gas and liquefied gas are then further separated by gas separation equipment to obtain methane, ethylene, propylene, and mixed C4 components, and the pyrolysis gasoline is further separated to obtain pyrolysis light gasoline and heavy gasoline. The methods for separating ethylene and propylene from the reaction products are similar to conventional methods in the art and are not limited by the present invention and will not be described in detail here.

[0070] In one embodiment, the cracking reactor is selected from one or more of a fast bed, a dilute phase transport bed (riser), a dense phase fluidized bed reactor, and a downer, or a combination of two or more of the same type of reactor, wherein the combination includes series and / or parallel connection. The riser is selected from one or more of a constant diameter riser, a constant linear velocity riser, and various variable diameter risers.

[0071] In one embodiment, the heavy feedstock oil is a mixture of one or more selected from petroleum hydrocarbons, non-petroleum hydrocarbon mineral oils, synthetic oils, animal fats and vegetable oils. Petroleum hydrocarbons are well known to those skilled in the art. For example, it can be vacuum gas oil, atmospheric residue oil, vacuum gas oil mixed with part of vacuum residue oil or other hydrocarbon oils obtained by secondary processing. The hydrocarbon oils obtained by other secondary processing are one or more selected from coker gas oil, deasphalted oil, and furfural refined raffinate oil. Non-petroleum hydrocarbon mineral oil is a mixture of one or more selected from coal liquefaction oil, oil sand oil and shale oil. Synthetic oil is a distillate oil obtained by FT synthesis of coal, natural gas or asphalt.

[0072] In one embodiment, the properties of the heavy feedstock oil meet one, two, three or four of the following indicators: density at 20°C 850-920 kg / m 3 , residual carbon 0-2% by weight, characteristic factor K value greater than 12.1, saturated hydrocarbon content 60%-100% by weight.

[0073] In one embodiment, the catalytic cracking catalyst comprises zeolite, inorganic oxide and optional clay. On a dry basis and based on the dry basis weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises 1 to 60 weight percent of zeolite, 5 to 99 weight percent of inorganic oxide and 0 to 70 weight percent of clay. The zeolite comprises large-pore zeolite and medium-pore zeolite, with the large-pore zeolite accounting for 50 to 80 weight percent of the total weight of the zeolite and the medium-pore zeolite accounting for 20 to 50 weight percent of the total weight of the zeolite. The medium-pore zeolite is selected from ZSM series zeolites and / or ZRP zeolites, and the above-mentioned medium-pore zeolites can also be modified with non-metallic elements such as phosphorus and / or transition metal elements such as iron, cobalt and nickel. A more detailed description of ZRP zeolite can be found in U.S. Patent No. 5,232,675A. The ZSM series zeolite is preferably selected from ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48 and a mixture of one or more of other zeolites of similar structure. For a more detailed description of ZSM-5, see U.S. Patent No. 3,702,886A.

[0074] The large-pore zeolite is one or more selected from the group consisting of rare earth Y (REY), rare earth hydrogen Y (REHY), ultrastable Y obtained by different methods, and high-silicon Y.

[0075] According to the present application, the inorganic oxide as a binder is selected from silicon dioxide (SiO2) and / or aluminum oxide (Al2O3). The clay as a matrix (ie, carrier) is selected from kaolin and / or halloysite.

[0076] In one embodiment, the conditions for the catalytic cracking reaction of the heavy crude oil include: a reaction temperature of 510-650° C., a reaction time of 1-20 seconds, a catalyst-oil weight ratio of (3-30):1, a weight ratio of pre-lift gas to crude oil of (0.03-1.0):1, and a reaction pressure of 130-450 kPa.

[0077] In one embodiment, the heavy feedstock is introduced into the cracking reactor at one location, or the feedstock is introduced into the cracking reactor at more than one location, which may be the same or different.

[0078] In one embodiment, the C4 component separated from the reaction product is introduced into a cracking reactor as a C4 component feedstock from one or more of the same or different locations to contact and react with a catalytic cracking catalyst.

[0079] In this application, the C4 component refers to low-molecular-weight hydrocarbons that exist in gaseous form at room temperature and pressure, primarily composed of the C4 fraction, including alkanes, alkenes, and alkynes with 4 carbon atoms in their molecules. This includes the C4 fraction-rich gaseous hydrocarbon product produced by the apparatus of the present invention, as well as C4 fraction-rich gaseous hydrocarbons produced by other apparatuses and processes. The C4 fraction produced by the apparatus of the present invention is preferred. The C4 hydrocarbons are preferably olefin-rich C4 fractions, with a C4 olefin content greater than 50% by weight, preferably greater than 60% by weight, and most preferably greater than 70% by weight.

[0080] In one embodiment, the light gasoline component separated from the reaction product is introduced into a cracking reactor from one or more locations, the same or different, as a light gasoline feedstock, to contact and react with a catalytic cracking catalyst.

[0081] In the application, light gasoline refers to hydrocarbons primarily composed of C5-C6 hydrocarbons, including alkanes with 5 or 6 carbon atoms, olefins, and a small amount of aromatic hydrocarbons. This includes C5-C6-rich fractions produced by the apparatus of the present invention, as well as C5-C6-rich fractions produced by other processes. The apparatus of the present invention is preferred for producing light gasoline. The light gasoline is preferably an olefin-rich fraction, with an olefin content greater than 50% by weight, preferably greater than 60% by weight.

[0082] like Figure 1 As shown, the catalytic cracking coke generator 300 of the present application is suitable for adjusting heat balance. The coke generator 300 includes, from bottom to top, a pre-lifting zone I, a coke generation reaction zone II, and an outlet zone III.

[0083] The coke generator 300 is equipped, from bottom to top, with a pre-lift gas inlet 301, a catalyst inlet 303, and a coke feedstock inlet 302. The pre-lift gas inlet 301 is typically located in pre-lift zone I, typically at the bottom of the zone. The catalyst inlet 303 can be located in pre-lift zone I and / or coke generation reaction zone II, but is typically located in the lower portion of the zone I, but above the pre-lift gas inlet 301, allowing the pre-lift gas to lift the incoming catalyst. This allows for pre-acceleration and pre-fluidization of the regenerated catalyst, improving its distribution and facilitating uniform contact and rapid mixing with the fuel oil.

[0084] The bottom of the regenerator 500 (such as Figure 2 The catalyst inlet 303 (shown) is connected to the coke generator 300, allowing the catalyst to enter the coke generator to form coke, thereby producing a coked catalyst. The top of the coke generator 300 is connected to the oil separation device 201, which separates the coked catalyst from the reaction oil and gas.

[0085] In one embodiment, the pre-lifting zone I, the coking reaction zone II, and the outlet zone III are connected in sequence, that is, the top of the pre-lifting zone I is connected to the coking reaction zone II, and the top of the coking reaction zone II is connected to the outlet zone III.

[0086] In the present application, the pre-lift gas inlet 301, the regenerated catalyst inlet 303, and the coke raw material inlet 302, which are independently provided on the coke maker 300, are located at different heights of the coke maker 300. Preferably, the coke maker 1 is provided with the pre-lift gas inlet 301, the regenerated catalyst inlet 303, and the coke raw material inlet 302 in order from bottom to top, and all are located at the lower part of the coke maker 300.

[0087] In the present application, the reaction zone II of the coke generator 300 is a bubbling bed or a turbulent fluidized bed. In one embodiment, the reaction zone II is a hollow cylinder with an aspect ratio of 20:1 to 2:1.

[0088] In the present application, the coke maker may be provided with one or more, for example, one, two, or more, coke raw material inlets 302. Each of the one or more coke raw material inlets may be independently located at the outlet of the coke maker's pre-elevation zone I, or at the bottom or sidewall of the coke reaction zone II. Further preferably, each of the coke raw material inlets 302 is independently located mid-upstream of the coke maker 300. Further preferably, each of the coke raw material inlets 302 is independently located at a distance h from the bottom of the coke maker, ranging from 5% to 15% of the coke maker's height.

[0089] In the present application, the fuel oil injected through the raw coke feed inlet 302 may include straight-run distillate oil or secondary processed distillate oil. Preferably, the secondary processed distillate oil may be a mixture of one or more selected from catalytic cracking diesel, catalytic cracking slurry oil, coker gasoline, coker diesel, and coker gas oil.

[0090] In one embodiment, the pre-elevation zone I is hollow cylindrical with an aspect ratio of 10:1 to 2:1. In one embodiment, the outlet zone III is hollow cylindrical with an aspect ratio of 30:1 to 5:1. In one embodiment, the ratio of the inner diameters of the pre-elevation zone I, the coking reaction zone II, and the outlet zone III is 1:2:1 to 1:10:1.

[0091] In one embodiment, the coke generator 300 is coaxially arranged with the settling stripper 200 and located below the oil-agent separation device 201. The outlet area of the coke generator 300 is connected to the oil-agent separation device 201, allowing the coke generator's material to enter the oil-agent separation device for separation into oil, gas, and coke-bearing catalyst. In one embodiment, the outlet end 304 of the coke generator 300 is connected to the inlet of the oil-agent separation device 201. In one embodiment, the oil-agent separation device 201 is housed within the settling stripper 200, allowing the spent catalyst and coke-bearing catalyst separated by the oil-agent separation device 201 to settle within the settling stripper 200.

[0092] In one embodiment, the decanter stripper 200 includes a stripping section 205 located at the lower portion of the decanter stripper. The stripping section 205 is configured to strip the collected coke-bearing catalyst and spent catalyst (i.e., the first spent catalyst and the second spent catalyst). Furthermore, the regenerator 500 is connected to the stripping section 205, so that the stripped first spent catalyst and the second spent catalyst are delivered to the regenerator 500. A stripping gas inlet 207 is provided at the lower portion of the stripping section 205 for inputting a stripping gas, such as steam.

[0093] It should be noted that the oil separation device 201 is also connected to the outlet of the catalytic cracking reactor 100, so that the material of the catalytic cracking reactor 100 is also separated by the oil separation device 201, and the separated catalyst to be regenerated enters the catalytic cracking regeneration system for regeneration circulation.

[0094] In one embodiment, the coke generator 300 is fluidically connected to the oil-agent separation device 201. After the reaction oil and coke-bearing catalyst produced by the coke generator 300 are separated by the oil-agent separation device 201, the reaction oil and gas are collected in the gas collecting chamber 202 and introduced into the reaction product separation system via the oil-gas pipeline 203 for recycling. The coke-bearing catalyst enters the stripping section 205 at the bottom of the settling stripper 200. After stripping, it is introduced into the regenerator 500 via the standpipe 206 for charring and releasing heat. In this application, the oil-agent separation device 201 can be a device familiar to those skilled in the art, such as a cyclone separator.

[0095] In one embodiment, the coking reaction conditions include: a coke generator outlet temperature of 460-560°C, a reaction time of 1-20 seconds, a catalyst-to-oil weight ratio of 3-30:1, a pre-lift gas to coke feed weight ratio of 0.01-0.5:1, a linear velocity of 0.2-1.2 m / s, and a catalyst particle density of 300-700 kg / m³. In one embodiment, the amount of coke feed injected can be 10-50% of the total weight of the feedstock introduced into the catalytic cracking reactor.

[0096] In one embodiment, the coke-forming raw material is slurry oil produced by the plant and secondary process distillate, or a mixture thereof. Preferably, the secondary process distillate can be selected from a mixture of one or more of catalytically cracked diesel, catalytically cracked diesel, catalytically cracked slurry oil, catalytically cracked slurry oil, coker gasoline, coker diesel, and coker gas oil. More preferably, the coke-forming raw material is slurry oil produced by the plant.

[0097] In one embodiment, the coke raw material is introduced into the coke maker at one location, or the coke raw material is introduced into the coke maker at more than one same or different location.

[0098] In one embodiment, the linear velocity of the reaction zone of the coke generator is 0.2 m / s to 1.2 m / s, and the catalyst particle density is 300 kg / m3 to 700 kg / m3.

[0099] In one embodiment, the pre-lift gas is selected from water vapor, nitrogen, dry gas, rich gas or C4 fraction or a mixture thereof, and the mass ratio of the pre-lift gas to fuel oil is 0.01:1 to 0.05:1.

[0100] In one embodiment, the coke raw material comprises straight-run distillate or secondary processed distillate. Preferably, the secondary processed distillate can be selected from a mixture of one or more of catalytic cracking diesel, coker gasoline, coker diesel and coker gas oil.

[0101] In one embodiment, the atomizing medium of the coke raw material may be selected from water vapor, nitrogen or a mixture thereof, and the mass ratio of the atomizing medium to the combustion oil is 0.01:1 to 0.5:1.

[0102] In one embodiment, the outlet temperature of the coke generator is 460-560°C.

[0103] like Figure 2 As shown, the regenerator 500 is used to regenerate the catalyst to be regenerated. The lower part is provided with an oxygen-containing gas inlet 501, a regenerated catalyst inlet 505 and two regenerated catalyst outlets 506 and an outlet 508. A cyclone separator 503 is provided inside and a flue gas outlet 504 is provided on the top.

[0104] like Figure 2 As shown, the first regenerated catalyst outlet 508 is connected to the regenerated catalyst inlet 103 of the catalytic cracking reactor, so that at least a portion of the regenerated catalyst is recycled back to the catalytic cracking reactor 100. In one embodiment, the bottom end of the pre-lift zone of the coke generator and / or the bottom end of the coke generation reaction zone is configured to be connected to the second regenerated catalyst outlet 506 of the regenerator for transporting at least a portion of the regenerated catalyst of the regenerator to the coke generator. In one embodiment, the second regenerated catalyst outlet 506 of the regenerator 500 (such as Figure 2 (as shown) is connected to the coke generator 300 via a catalyst inlet 303, allowing the catalyst to enter the coke generator to generate coke, thereby producing a coked catalyst. In one embodiment, a portion of the regenerated catalyst is returned to the catalytic cracking reactor, and a portion is returned to the coke generator for recycling. The weight ratio of the regenerated catalyst recycled to the catalytic cracking reactor to the regenerated catalyst recycled to the coke generator can be 1:1 to 10:1, for example, 2:1 to 10:1.

[0105] The conditions of the regenerator are: regeneration temperature is 550-750°C, preferably 600-730°C, more preferably 650-700°C; gas superficial velocity is 0.5-3 m / s, preferably 0.8-2.5 m / s, more preferably 1-2 m / s; the average residence time of the catalyst to be regenerated is 0.6-3 minutes, preferably 0.8-2.5 minutes, more preferably 1-2 minutes.

[0106] In the catalytic cracking system provided herein, the decanter stripper, oil separation equipment, regenerator, other devices, reaction product separation system, etc. may all be devices well known to those skilled in the art, and the connections between these devices may also be made in accordance with methods known in the art. For example, the oil separation equipment may include a cyclone separator and an outlet rapid separator.

[0107] The catalytic cracking system of the present application includes a coking device, which can regenerate the coke-bearing catalyst from the coking device and the catalyst to be regenerated from the catalytic cracking reactor together in the regenerator, release heat, and the regenerated catalyst carrying the heat is circulated back to the catalytic cracking reactor to provide heat for the reaction. The catalytic cracking system of the present application is suitable for catalytic cracking of various raw materials and insufficient coke, such as the reaction of catalytic cracking of petroleum hydrocarbons and oxygenated hydrocarbons to produce propylene or fuel oil, or the reaction of catalytic cracking to produce light olefins. It should be noted that although the coking device in the catalytic cracking system of the present application also sprays coke raw materials, the main purpose of the coke raw materials is not to be used as feedstock oil for catalytic cracking, but to be used to supplement coke on the catalyst, which is beneficial to the thermal balance of the catalytic cracking reaction.

[0108] In the present application, a coking device is provided to mix the coking raw materials with the catalyst under low-temperature, oxygen-free fluidized conditions, and a coking reaction occurs in a coking reaction zone having the characteristics of a bubbling bed or a turbulent fluidized bed. This not only achieves high coke selectivity, but also makes the coke evenly distributed on the catalyst, which is conducive to uniform combustion in the regeneration system.

[0109] In the present application, the coke-containing catalyst generated by the coke generator can be mixed with the coke-containing catalyst generated by the catalytic cracking reactor and enter the regeneration system, where it can be fully burned and released heat under the action of high-temperature, oxygen-rich gas to supply the heat required for the reaction without damaging the properties of the catalyst. This realizes the replenishment of coke source from the reaction system end and solves the thermal balance problem of the catalytic cracking device.

[0110] The present application has a simple structure and only requires adaptive modification of the reactor system. The regeneration system still uses existing technology, is easy to implement, and has strong applicability. In particular, it is suitable for catalytic cracking units with light olefins and other chemical raw materials as the main target products. It can not only fundamentally solve the problem of heat balance, but also reduce the damage to the catalyst and regeneration system caused by the traditional method of spraying combustion oil, thereby saving catalyst costs and improving the economic benefits of the refinery.

[0111] The present application will be further described below with reference to the preferred embodiments shown in the accompanying drawings, but the present application is not limited thereby.

[0112] Figure 2 A preferred embodiment of the catalytic cracking reaction system of the present application is given.

[0113] The pre-lift gas enters the cracking reactor from the bottom of the cracking reactor 100 through the pre-lift gas inlet 101. The high-temperature regenerated catalyst from the regenerator enters the lower part of the cracking reactor 100 through the catalyst inlet 103, mixes with the pre-lift gas, and moves upward, contacting the feedstock oil from the feedstock oil inlet 102 to cause a catalytic cracking reaction. The carbonized catalyst and the oil and gas generated by the reaction flow upward and enter the oil agent separation device 201 through the outlet 104.

[0114] The pre-lift gas enters the coke maker 300 from the bottom through the pre-lift gas inlet 301. The high-temperature regenerated catalyst from the regenerator enters the lower part of the coke maker 300 through the catalyst inlet 303, mixes with the pre-lift gas, moves upward, and contacts the coke raw materials from the coke raw material inlet 302. Together, they enter the coke maker and undergo a coking reaction. The catalyst with carbon and the oil and gas generated by the reaction flow upward and enter the oil-agent separation device 201 through the outlet area 304.

[0115] The reaction oil and gas separated by the oil agent separation equipment 201 enter the gas collecting chamber 202 and are introduced into the product separation system through the oil and gas pipeline 203; the separated coke-carrying catalyst enters the stripping section 205 of the settling stripper 200. After stripping, part of the catalyst to be regenerated enters the regenerator 500 through the standpipe 206 and the catalyst inlet 505; the oxygen-containing gas from the oxygen-containing gas inlet 501 enters the regenerator after passing through the gas distributor 502, contacts the coke-carrying catalyst to cause a complete combustion reaction, and completely releases heat. Part of the regenerated catalyst enters the cracking reactor 100 through the regenerated catalyst outlet 508 for recycling, and part of the catalyst is sent to the coke generator for recycling through the regenerated catalyst outlet 506 and the catalyst inlet 303. The regenerated flue gas is recovered by the cyclone separator 503 to remove the entrained catalyst and is sent to the subsequent energy recovery system through the flue outlet 504.

[0116] Example

[0117] The following examples further illustrate the present invention but are not intended to limit the present invention. The catalyst used in the experiments was an industrial catalyst with the trade name SHMP-4; the raw coke feedstock was catalytic cracking slurry oil obtained from the catalytic cracking unit of Anqing Petrochemical Company. The properties are shown in Table 1.

[0118] Example 1

[0119] exist Figure 2 The system was tested, wherein the catalytic cracking reactor was a riser reactor;

[0120] The coke generator 300 used includes:

[0121] Pre-lifting zone I, with a length of 1 meter and an inner diameter of 0.2 meters;

[0122] Coke-generating reaction zone II is a turbulent bed reactor with a length of 3 meters and an inner diameter of 0.4 meters;

[0123] The outlet zone III has a length of 2 meters and an inner diameter of 0.2 meters.

[0124] The coke maker is provided with a pre-lift gas inlet 301 , a regenerated catalyst inlet 303 , and a coke raw material inlet 302 in sequence from bottom to top, and all are located at the lower part of the coke maker 300 .

[0125] The distance between the coke raw material inlet 302 and the bottom of the coke maker is independently 10% of the height of the coke maker.

[0126] A cracking reaction experiment using Daqing wax oil was conducted in a riser reactor. Preheated feedstock was introduced from the bottom of the cracking reactor, where it came into contact with regenerated catalyst from the regenerator and a catalytic cracking reaction proceeded from bottom to top. This produced a mixture of reaction products and regenerated catalyst. The oil mixture then passed from the reactor outlet into a cyclone separator, rapidly separating the reaction products from the regenerated catalyst. The reaction products were then cooled and collected. The properties of the Daqing wax oil used are shown in Table 3.

[0127] The pre-lifting medium nitrogen enters the lower part of the coking vessel and mixes with the regenerated catalyst before flowing upward. The mixture of Anqing slurry oil (coking raw material) and atomized medium (water vapor) enters the coking vessel through the coking raw material inlet, contacts the hot regenerated catalyst and undergoes a coking reaction. The reaction products and the catalyst to be regenerated enter the cyclone separator 201 from the coking vessel outlet (outlet area), where the reaction products and the catalyst to be regenerated are quickly separated and the reaction products are collected after cooling.

[0128] The spent catalyst and the charred catalyst flow by gravity into the stripping section of the settler, where steam strips the hydrocarbon products adsorbed on the spent catalyst. The stripped spent catalyst then enters the regenerator, where it is regenerated by contact with air. The regenerated catalyst is then returned to the reactor and coke generator for recycling. The weight ratio of regenerated catalyst recycled to the catalytic cracking reactor to regenerated catalyst recycled to the coke generator is 5:1. The operating conditions and product distribution are listed in Table 2.

[0129] From the results in Table 2, it can be seen that the methane yield is 1.92%, the ethylene yield is 5.39% by weight, the propylene yield is 21.96% by weight, and the coke yield is 8.47%.

[0130] Comparative Example 1

[0131] according to Figure 2 The experiment was conducted with reference to the process of Example 1, except that the coke generator was not turned on in Comparative Example 1, that is, the catalyst was regenerated as follows:

[0132] The spent catalyst enters the stripping section of the settler under gravity, where steam strips the hydrocarbon products adsorbed on the spent catalyst. The stripped catalyst then enters the regenerator, where it is regenerated by contact with air. Simultaneously, Anqing slurry oil is introduced into the regenerator bed as fuel, replenishing the regenerator's heat. The regenerated catalyst is then returned to the reactor for recycling. The operating conditions and product distribution are listed in Table 2.

[0133] From the results in Table 2, it can be seen that the methane yield was 2.37%, the ethylene yield was 5.09 wt %, the propylene yield was 20.01 wt %, and the coke yield was 4.37%.

[0134] It can be seen from the results of Example 1 and Comparative Example 1 above that the catalytic cracking reaction system of the present application can not only reduce the methane yield and increase ethylene and propylene, but also provide the required coke source for the regeneration process.

[0135] In the description of this application, it should be noted that the terms "upper", "lower", "inside", "outside", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships in the working state of this application. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on this application.

[0136] In the description of this application, it should be noted that, unless otherwise specified or limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0137] The present application has been described above in conjunction with preferred embodiments, but these embodiments are merely exemplary and serve only as an illustrative example. On this basis, various replacements and improvements can be made to the present application, all of which fall within the scope of protection of the present application.

[0138] Table 1 Properties of cracking reaction raw materials and coke raw materials

[0139]

[0140] Table 2 Operating conditions and results of Example 1 and Comparative Example 1

[0141]

Claims

1. A catalytic cracking reaction-regeneration system comprising: Catalytic cracking reactor, coke generator, Oil separation equipment, settling strippers, and Regenerator, The catalytic cracking reactor is provided with a pre-lift gas inlet, a regenerated catalyst inlet, a cracking feedstock oil inlet and an oil agent outlet; The oil agent outlet of the catalytic cracking reactor is connected to the oil agent separation device, so that the oil agent of the catalytic cracking reactor enters the oil agent separation device and is separated into a first reaction product and a first spent catalyst; The coke generator is coaxially arranged with the settling stripper, and the coke generator comprises, from bottom to top, the following components: A pre-lift zone, wherein the pre-lift gas used is selected from steam, nitrogen, dry gas, rich gas or C4 fraction or a mixture thereof; a coking reaction zone, wherein the coking reaction zone is a bubbling fluidized bed or a turbulent fluidized bed, wherein the outlet temperature of the coking device is 460-560° C., the linear velocity in the coking reaction zone is 0.2 m / s-1.2 m / s, and the catalyst particle density is 300 kg / m3-700 kg / m3; and Export Zone, wherein the top of the pre-lifting zone is connected to the coke-generating reaction zone, and the top of the coke-generating reaction zone is connected to the outlet zone; The coke maker is provided with one or more coke raw material inlets, and the one or more coke raw material inlets are independently arranged at the outlet end of the coke maker pre-lifting zone, or at the bottom or side wall of the coke reaction zone; The outlet area of the coke generator is connected to the oil-agent separation device, so that the material of the coke generator enters the oil-agent separation device and is separated into the second reaction product and the second catalyst to be generated; The oil separation device is accommodated inside the settling stripper, so that the first catalyst to be regenerated and the second catalyst to be regenerated separated by the oil separation device are settled in the settling stripper; and the settling stripper is connected to the regenerator, so that the first catalyst to be regenerated and the second catalyst to be regenerated in the settling stripper are transported to the regenerator; The regenerator is provided with a first regenerated catalyst outlet and a second regenerated catalyst outlet, wherein the first regenerated catalyst outlet is connected to the regenerated catalyst inlet of the catalytic cracking reactor, so that at least a portion of the regenerated catalyst is circulated back to the catalytic cracking reactor; The bottom end of the pre-lifting zone of the coke maker and / or the bottom end of the coke forming reaction zone is configured to communicate with the second regenerated catalyst outlet of the regenerator for conveying at least a portion of the regenerated catalyst of the regenerator to the coke maker.

2. The system according to claim 1, wherein: The coking device is provided with a pre-lift gas inlet, a catalyst inlet and one or more coking raw material inlets in sequence from bottom to top.

3. The system according to claim 2, characterized in that The distance between the one or more coke making raw material inlets and the bottom of the coke making vessel is independently 5% to 15% of the height of the coke making vessel.

4. The system according to claim 1, wherein: The coke-generating reaction zone is in the shape of a hollow cylinder, and its aspect ratio is 20:1 to 2:

1.

5. The system according to claim 4, characterized in that The pre-lifting area is a hollow cylinder with a length-to-diameter ratio of 10:1-2:1; The outlet area is a hollow cylinder with a length-to-diameter ratio of 30:1-5:

1.

6. The system according to claim 5, characterized in that The ratio of the inner diameters of the pre-lifting zone, the coking reaction zone and the outlet zone is 1:2:1 to 1:10:

2.

7. A method for catalytic cracking of heavy crude oil, carried out in the catalytic cracking reaction-regeneration system according to any one of claims 1 to 6, the method comprising: 1) introducing the heavy crude oil into the catalytic cracking reactor, contacting it with the regenerated catalyst from the regenerator and performing a catalytic cracking reaction to obtain a first reaction product and a first catalyst to be regenerated; 2) The coking raw material is brought into contact with the regenerated catalyst from the regenerator and a coking reaction is carried out from bottom to top to obtain a second reaction product and a second catalyst. 3) introducing the first reaction product and the second reaction product into a separation system for separation, 4) The first catalyst to be regenerated and the second catalyst to be regenerated are transported to the regenerator for charring and regeneration, and the regenerated catalysts are returned to the bottom of the catalytic cracking reactor and the coking vessel for recycling.

8. The method according to claim 7, wherein: The conditions for the catalytic cracking reaction include: a reaction temperature of 510-650° C., a reaction time of 1-20 seconds, a catalyst-oil weight ratio of (3-30):1, a pre-lift gas-to-raw oil weight ratio of (0.03-1.0):1, and a reaction pressure of 130-450 kPa.

9. The method according to claim 7, wherein: The conditions for the coking reaction include: a reaction time of 1-20 seconds, a catalyst-oil weight ratio of (3-30):1, and a weight ratio of pre-lifting gas to coking raw material of (0.01-0.5):

1.

10. The method according to claim 7, wherein: The properties of the heavy crude oil meet one, two, three or four of the following indicators: density at 20°C 850-920 kg / m 3 , residual carbon 0-2 weight%, characteristic factor K value is greater than 12.1, and saturated hydrocarbon content is 60 weight%-100 weight%.

11. The method according to claim 7, wherein: The heavy feedstock oil is one or a mixture of two or more selected from petroleum hydrocarbons, non-petroleum hydrocarbon mineral oils, synthetic oils, animal fats and vegetable fats.

12. The method according to claim 7, characterized in that The raw material for coking is the slurry oil produced by the device, or the secondary processed distillate oil, or a mixture thereof.

13. The method according to claim 12, characterized in that The secondary processed distillate oil is selected from a mixture of one or more of catalytic cracking diesel, catalytic cracking diesel, catalytic cracking slurry, catalytic cracking slurry, coker gasoline, coker diesel and coker gas oil.

14. The method according to claim 12, characterized in that The raw material for coking is the oil slurry produced by the plant.

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