Catalytic cracking reaction-regeneration system and method

Abstract

The application relates to a catalytic cracking reaction-regeneration system and method, which comprises a reactor, an oil agent separation device and a regeneration device. When the catalytic cracking reaction-regeneration system and method are used for light petroleum hydrocarbon catalytic cracking reaction, not only is the catalytic reaction selective, the ethylene and propylene yield is high, the methane yield is low, but also the problem of reaction heat balance is solved without damaging the properties of the catalyst.

Description

Technical Field

[0001] The present application relates to the field of petrochemical industry, and more specifically, to a catalytic cracking reaction-regeneration system and a catalytic cracking method. Background Art

[0002] Currently, domestic refining capacity is in excess, while terminal consumption of refined oil products is slowing. This creates an oversupply of refined oil products, a pressing issue for refining companies. Ethylene, a fundamental raw material for chemical products and known as the "mother of the petrochemical industry," is a key indicator of a country's petrochemical development. As living standards continue to improve, global demand for chemical products continues to grow, and so does the demand for ethylene and propylene, the fundamental raw materials for these products. Using low-cost, low-carbon catalytic cracking to convert petroleum hydrocarbons into ethylene and propylene not only accelerates the transformation and development of refining companies but also aligns with the industry's low-carbon transition to "oil production."

[0003] CN201510296090.8 discloses a naphtha conversion method that combines catalytic cracking of naphtha with steam cracking of light alkanes and catalytic cracking of higher alkanes and higher olefins to produce light olefins, light aromatics, and high-octane gasoline. Because most reactants are converted during the relatively low-temperature catalytic cracking, overall energy consumption can be reduced.

[0004] CN201910080462.1 discloses a naphtha-containing feedstock conversion device, comprising reacting the naphtha-containing feedstock in a fast fluidized bed reactor to produce product gas and a catalyst to be regenerated; then partially supplying the stripped catalyst to the fast fluidized bed reactor and partially supplying it to a regenerator. The device addresses the technical problem of reducing the impact of thermal cracking reactions in naphtha catalytic cracking technology and lowering the methane yield in the product.

[0005] CN 201811440380.5 discloses a process for producing propylene and aromatics through a low-temperature catalytic reaction using naphtha or light hydrocarbons as raw materials. The raw naphtha or light hydrocarbons undergo heat exchange in a heat exchanger and / or heating in a furnace before entering a fixed-bed reactor. A low-temperature catalytic reaction occurs under the action of a specific catalyst. The reaction products pass through a separation system to yield ethylene, propylene, C4 and C5 hydrocarbons, and by-product aromatics such as toluene and xylene. A portion of the C4 and C5 hydrocarbons are recycled back to the reactor.

[0006] Petroleum hydrocarbons, especially high-quality or light raw materials, have small molecules and high reaction activation energy, requiring higher reaction temperatures, which often leads to high by-product methane yields. In addition, the catalytic cracking reaction heat is large, requiring a lot of heat for the reaction, and the coke generated by the self-cracking often cannot meet the heat balance requirements of the reaction-regeneration system itself. The catalytic cracking reaction of light hydrocarbons such as naphtha produces low coke and requires a large amount of external fuel oil. Since catalytic cracking uses catalysts with molecular sieves as active components, the local high temperature generated by the combustion of fuel oil in the regenerator causes the molecular sieve framework aluminum to gradually escape, and the catalyst activity gradually decreases, resulting in a further decrease in the conversion rate of the reactants. Therefore, the catalytic cracking technology of light raw materials such as naphtha needs to continue to improve and develop, pursuing higher reaction conversion rates and reaction selectivity. The above-mentioned prior art proposes methods and catalysts for converting petroleum hydrocarbon raw materials into light olefins through a catalytic cracking reaction process, but fails to solve the problems of insufficient reaction heat and high methane yield during the cracking of light raw materials. Summary of the Invention

[0007] The purpose of this application is to provide a catalytic cracking reaction-regeneration system and method to improve the reaction selectivity of catalytic cracking of light raw materials to produce ethylene and propylene, reduce the methane yield, and solve the problem of insufficient heat during the catalytic cracking reaction of light raw materials.

[0008] The present application provides a catalytic cracking reaction-regeneration system, which comprises:

[0009] A catalytic cracking reactor, wherein the catalytic cracking reactor comprises, from bottom to top,:

[0010] optional pre-lift zone;

[0011] A reaction zone, the reaction zone comprising at least one reduced-diameter reaction section, the reduced-diameter reaction section being in the form of a hollow cylinder with a substantially circular cross-section and open bottom and top ends, the inner diameter of which decreases continuously or discontinuously from bottom to top; and

[0012] export zone;

[0013] wherein the optional pre-lifting zone is connected to the bottom end of the reaction zone, the top end of the reaction zone is connected to the outlet zone, and at least one raw material feed port is provided on the optional pre-lifting zone and / or the bottom end of the reaction zone;

[0014] The inner diameter of the cross section of the bottom end of the reaction zone is greater than or equal to the inner diameter of the cross section of the optional pre-elevation zone, and the inner diameter of the cross section of the top end is equal to or smaller than the inner diameter of the cross section of the optional pre-elevation zone and the inner diameter of the cross section of the outlet zone; a regenerated catalyst inlet is provided at the bottom of the reaction zone and / or the optional pre-elevation zone;

[0015] an oil-agent separation device, the oil-agent separation device being configured to communicate with the outlet area of ​​the catalytic cracking reactor so that the reaction oil gas and catalyst from the catalytic cracking reactor are separated in the oil-agent separation device, and the oil-agent separation device being provided with an outlet for the catalyst to be regenerated;

[0016] A regeneration device, comprising a coke generator and a regenerator, wherein the outlet of the coke generator is in fluid communication with the inlet of the regenerator so that material from the coke generator can flow into the regenerator; and the bottom of the coke generator is in fluid communication with the bottom of the regenerator via an external catalyst circulation pipe;

[0017] The coke maker is provided with an inlet for the catalyst to be generated, a connection port for an external catalyst circulation pipe, an inlet for the oxygen-depleted gas, and an inlet for the fuel oil in order from bottom to top; the inlet for the catalyst to be generated of the coke maker is connected to the outlet for the catalyst to be generated of the oil separation device, so that the catalyst to be generated enters the coke maker;

[0018] The regenerator is provided with an oxygen-rich gas inlet and a regenerated catalyst outlet, wherein the regenerated catalyst outlet of the regenerator is connected to the regenerated catalyst inlet, so that the regenerated catalyst is circulated back to the catalytic cracking reactor.

[0019] In one embodiment, the ratio of the inner diameter of the bottom cross-section of the reaction zone of the reactor to the total height of the reactor is 0.01:1 to 0.5:1; the ratio of the total height of the reaction zone to the total height of the reactor is 0.15:1 to 0.8:1.

[0020] In one embodiment, the reactor reaction zone includes 1-3 reduced diameter reaction sections.

[0021] Preferably, the reduced diameter reaction section of the reactor is in the form of a hollow truncated cone, and the longitudinal section is an isosceles trapezoid; the ratio of the inner diameter of its top cross-section to the height of the reduced diameter reaction section is independently 0.005-0.3:1, the ratio of the inner diameter of the bottom cross-section to the height of the reduced diameter reaction section is independently 0.015-0.25:1, and the ratio of the inner diameter of the bottom cross-section to the inner diameter of the top cross-section is independently greater than 1.2 and less than or equal to 10; the ratio of the height of the reduced diameter reaction section to the total height of the reactor is independently 0.15:1 to 0.8:1.

[0022] In one embodiment, the ratio of the inner diameter to the height of the pre-lifting zone of the reactor is 0.02-0.4:1; and the ratio of its height to the total height of the reactor is 0.01:1 to 0.2:1.

[0023] In one embodiment, the reactor pre-lifting zone is connected to the reaction zone by a first connecting section, the longitudinal section of the first connecting section is an isosceles trapezoid, and the outward inclination angle α of the side of the isosceles trapezoid is 5-85°.

[0024] In one embodiment, the ratio of the cross-sectional inner diameter to the height of the reactor outlet zone is 0.01-0.3:1, and the ratio of the height of the outlet zone to the total height of the reactor is 0.05:1 to 0.5:1.

[0025] In one embodiment, the distance from the connection port of the external catalyst circulation pipe to the bottom of the coke former is 5% to 10% of the height of the coke former.

[0026] The distance from the fuel oil inlet to the bottom of the coke former is independently 20% to 50% of the height of the coke former.

[0027] In one embodiment, the bottom of the coke former is provided with a first gas distributor, so that the oxygen-lean gas injected through the oxygen-lean gas inlet enters the coke former through the first gas distributor.

[0028] The outlet of the coke former is provided with a catalyst distribution plate, so that the catalyst passing through the coke former enters the regenerator through the catalyst distribution plate.

[0029] In one embodiment, the coke former is a hollow cylinder with an aspect ratio of 30:1 to 3:1.

[0030] In one embodiment, the bottom of the regenerator is provided with an opening, and the outlet of the coke former is connected to the regenerator through the opening.

[0031] In one embodiment, the oil agent separation device comprises a cyclone separator, which is connected to the outlet of the catalytic cracking reactor and arranged coaxially or horizontally with the catalytic cracking reactor.

[0032] The present application relates to a catalytic cracking method, which is carried out in the catalytic cracking reaction-regeneration system of the present application, comprising the following steps:

[0033] The preheated reaction raw material enters the pre-lifting zone and the reaction zone of the catalytic cracking reactor in sequence, and is in contact with and reacts with the regenerated catalyst from the regenerator. The reaction oil gas and the spent catalyst pass through the outlet zone and enter the oil agent separation device for gas-solid separation. The separated reaction oil gas is led out of the device, and further separation obtains ethylene, propylene, C4 hydrocarbon fraction and light aromatic-rich pyrolysis gasoline. The separated spent catalyst enters the coke former through the spent vertical pipe.

[0034] Injecting oxygen-depleted gas into the coking device through the oxygen-depleted gas inlet, the gas contacts the regenerated catalyst from the regenerator and the catalyst to be regenerated from the reactor, causing the catalyst to heat up and undergo a partial coking reaction, which causes the catalyst to move upward. The catalyst then contacts a mixture of an atomizing medium and combustion oil injected through the fuel oil inlet, causing a coking reaction and a partial coking reaction to occur, thereby obtaining a catalyst with a portion of coke.

[0035] The catalyst with some coke enters the regenerator and comes into contact with the oxygen-rich gas injected into the regenerator through the oxygen-rich gas inlet, undergoing a complete combustion reaction. The regenerated catalyst with restored activity is returned to the catalytic cracking reactor for recycling.

[0036] In one embodiment, the reaction raw material is selected from C4-C20 light crude oil.

[0037] In one embodiment, the reaction conditions in the reaction zone include: a reaction temperature of 510-750°C, preferably 550-700°C, a reaction time of 0.5-10 seconds, preferably 1-5 seconds, a catalyst-oil weight ratio of 10:1 to 50:1, preferably 20:1 to 40:1, and a fluidizing gas to coke raw material weight ratio of 0.05:1 to 2.0:1, preferably 0.2:1 to 0.8:1.

[0038] In one embodiment, the linear speed of the coke generator is 1.2 m / s to 2.2 m / s, and the oxygen content of the oxygen-depleted gas is 1% to 20%. More preferably, the oxygen content of the oxygen-depleted gas is 5% to 10%.

[0039] The oxygen content in the oxygen-rich gas of the regenerator is 21 volume % to 100 volume %, and more preferably, the oxygen content in the oxygen-rich gas is 21 volume % to 85 volume %.

[0040] In one embodiment, the atomizing medium is nitrogen, and the mass ratio of the atomizing medium to the combustion oil is 1:1 to 1:100.

[0041] In the catalytic cracking reactor of the present application, the reduced-diameter reaction section, especially the conical reaction section, has a large bottom space, which can effectively increase the catalyst density in the reactor, thereby greatly increasing the ratio of catalyst to reaction raw materials in the reactor, strengthening the primary cracking reaction of the raw materials, not only improving the reaction conversion rate, but also increasing the yield of light olefins; moreover, the reduced-diameter reaction section, especially the reduced-diameter structure of the conical reaction section, is conducive to accelerating the reaction oil and gas to leave the reaction zone, shortening the reaction time, and reducing catalyst backmixing, which is conducive to reducing the secondary conversion reaction of the light olefins generated by the primary reaction and improving the selectivity of light olefins.

[0042] The coke forming device provided by the application is simple in structure and easy to implement. The coke forming device can be implemented by adaptive modification of an existing industrial device regenerator, and has strong applicability. In particular, for a catalytic cracking device taking low-carbon olefins and other chemical raw materials as main target products, the coke forming device can not only fundamentally solve the heat balance problem, but also reduce the damage to the catalyst and the regeneration system caused by the traditional fuel oil injection method, thereby saving the catalyst cost and improving the economic benefit of the refinery. When the regeneration device and method of the application are used in a fluidized catalytic cracking reaction with less coke formation, the heat balance of the reaction-regeneration process is achieved, and the temperature of the catalyst rises uniformly during the coke burning process in the regenerator, without local hot spots, and the physical and chemical properties of the catalyst are not damaged.

[0043] In the application, the stripper of the traditional catalytic cracking device is cancelled, which not only reduces the amount of water vapor, but also allows the oil gas entrained by the spent catalyst to enter the regeneration system for coke burning, thereby to some extent, the heat balance problem is also alleviated.

[0044] The catalytic cracking reactor and system of the application can be used to efficiently produce ethylene, propylene and other chemical raw materials from light petroleum hydrocarbons, thereby helping the refinery to transform, develop and extend from oil refining to chemical raw material production, solving the problem of shortage of petrochemical raw materials, and improving the economic benefit of the refinery. When the reactor and system of the application are used in catalytic cracking reaction, the contact efficiency of the raw material and the catalyst is high, the selectivity of the catalytic reaction is good, the yield of high value-added products such as ethylene and propylene is high, and the yield of by-products such as methane is low. BRIEF DESCRIPTION OF DRAWINGS

[0045] The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and serve to explain the principles of the application, but do not limit the application. In the drawings:

[0046] Figure 1 A schematic diagram of a catalytic cracking reactor according to an embodiment of the application.

[0047] Figure 2 A schematic diagram of a regeneration device according to an embodiment of the application.

[0048] Figure 3 A schematic diagram of a catalytic cracking reaction-regeneration system according to an embodiment of the application. DETAILED DESCRIPTION

[0049] The application will be further described in detail below with reference to the accompanying drawings and examples. Through these descriptions, the features and advantages of the application will become more apparent.

[0050] 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.

[0051] Any specific numerical value disclosed herein (including the endpoints of a numerical range) is not limited to the exact value of the numerical value, but should be understood to also include values ​​close to the exact value, such as all possible values ​​within ±5% of the exact value. Moreover, for a disclosed numerical range, any combination of the endpoints of the range, between the endpoints and the specific points in the range, and between the specific points 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] like Figure 1 As shown, the present application provides a catalytic cracking reactor, which comprises, from bottom to top:

[0056] Optional pre-lift zone I,

[0057] Reaction zone II, wherein the reaction zone II includes at least one reduced-diameter reaction section, wherein the reduced-diameter reaction section is a hollow cylinder with a substantially circular cross-section and open bottom and top ends, and the inner diameter of the hollow cylinder decreases continuously or discontinuously from bottom to top; and

[0058] Export Zone III,

[0059] The optional pre-elevation zone I is connected to the bottom end of the reaction zone II, the top end of the reaction zone II is connected to the outlet zone III, and at least one raw material feed port 102 is provided on the optional pre-elevation zone and / or the bottom end of the reaction zone;

[0060] The cross-sectional inner diameter of the bottom end of the reaction zone II is greater than or equal to the cross-sectional inner diameter of the optional pre-lift zone I, and the cross-sectional inner diameter of the top end is equal to or less than the cross-sectional inner diameter of the optional pre-lift zone and the cross-sectional inner diameter of the outlet zone.

[0061] like Figure 1 As shown, the catalytic cracking reactor may include the pre-lifting zone I, which is arranged at the bottom of the catalytic cracking reactor and is used to pre-lift the catalyst entering the reactor. Figure 1 As shown, a catalyst inlet 103 is provided at the lower part of the pre-lifting zone I for inputting the catalyst. The pre-lifting zone I can be a hollow cylindrical structure, and the ratio of its inner diameter to height is 0.02-0.4:1; the ratio of its height to the total height of the reactor is 0.01:1 to 0.2:1, preferably 0.05:1 to 0.15:1. In one embodiment, the inner diameter of the pre-lifting zone I can be 0.2-5 meters, preferably 0.4-3 meters. In an embodiment in which a pre-lifting zone I is present, a pre-lifting medium can be input into the pre-lifting zone I through a pre-lifting medium pipeline 8. In an embodiment in which a pre-lifting zone I is present, at least one catalyst inlet 103 can also be provided at the bottom of the pre-lifting zone I for allowing the catalyst to pass through the pre-lifting zone I and enter the reactor.

[0062] According to the present application, the pre-lift zone I is not necessary. For example, when the reaction zone II of the reactor of the present application is used in series with other reactors such as a riser reactor, the reaction zone II can be directly connected to the outlet of the other reactor located upstream without the need to use the pre-lift zone I. In one embodiment, the catalytic cracking reactor may not include the pre-lift zone I. At this time, the bottom of the reaction zone II may be provided with at least one raw material feed port 102 to facilitate the entry of raw materials and the like into the catalytic cracking reactor. In an embodiment in which there is no pre-lift zone I, the bottom of the reaction zone II may be provided with at least one catalyst inlet (not shown) for allowing the catalyst to enter the reactor. Of course, the reaction zone II may not be provided with a catalyst inlet, and the catalyst therein may be derived from the catalyst carried in the logistics of other reactors. Both embodiments are within the scope of protection of the present application.

[0063] like Figure 1As shown, the catalytic cracking reactor may include a reaction zone II. A pre-lift zone I is connected to the bottom end 210 of the reaction zone II, and the top end 220 of the reaction zone II is connected to the outlet zone III. At least one catalyst inlet 103 and at least one raw material feed port 102 are provided on the pre-lift zone and / or at the bottom of the reaction zone. The inner diameter of the cross section of the bottom end 210 of the reaction zone II is greater than or equal to the inner diameter of the cross section of the pre-lift zone I, and the inner diameter of the cross section of the top end 220 is equal to or less than the inner diameter of the cross section of the pre-lift zone I and the inner diameter of the cross section of the outlet zone III.

[0064] In the catalytic cracking reactor provided in the present application, the reaction zone II is a fluidized bed. Preferably, the fluidized bed is one or a combination of a transport fluidized bed, a turbulent fluidized bed and a fast bed.

[0065] In one embodiment, the pre-elevation zone I is connected to the reaction zone II via a first transition section I-1. The longitudinal section of the first transition section I-1 may be an isosceles trapezoid, and the outward inclination angle α of the side of the isosceles trapezoid may be 5-85°, preferably 15-75°.

[0066] like Figure 1 As shown, the raw material feed port 9 can be provided at the upper portion of the pre-elevation zone I, in the first transition section I-1, or at the lower portion of the reaction zone II. In particular, in an embodiment where the pre-elevation zone I is not present, a raw material feed port 102 can be provided at the lower portion of the reaction zone II for feeding raw materials.

[0067] In one embodiment, the ratio of the inner diameter of the bottom cross-section of the reaction zone II to the total height of the reactor is 0.01:1 to 0.5:1, preferably 0.05:1 to 0.2:1; the ratio of the total height of the reaction zone II to the total height of the reactor is 0.15:1 to 0.8:1, for example 0.2:1 to 0.75:1.

[0068] like Figure 1 As shown, the reaction zone II includes at least one diameter-reducing reaction section, which is a hollow cylinder with a roughly circular cross-section and open bottom and top ends, and its inner diameter decreases continuously or discontinuously from bottom to top.

[0069] In this application, "reduced diameter" refers to a decrease in inner diameter in a discontinuous manner, such as steps or jumps, or in a continuous manner. An example of a "reduced diameter section with a discontinuous decrease in inner diameter from bottom to top" includes a column consisting of two or more hollow cylinders with decreasing inner diameters.

[0070] For example, the reaction zone II may be cylindrical, including one or more hollow truncated cone sections, or may be cylindrical, including two or more hollow cylindrical sections. According to the present application, when the reaction zone includes two or more reduced diameter reaction sections, the reduced diameter reaction sections may have the same or different heights, and this application does not impose strict restrictions on this.

[0071] In a preferred embodiment, the reaction zone II comprises a cylindrical form consisting of one or more hollow truncated conical segments and optional connecting segments for connecting adjacent hollow truncated conical segments, or a cylindrical form consisting of two or more hollow cylindrical segments and optional connecting segments for connecting adjacent hollow cylindrical segments.

[0072] In one embodiment, Figure 1 As shown, the reaction zone II includes a reduced diameter reaction section, which is in the form of a hollow truncated cone, and its longitudinal section is an isosceles trapezoid; the inner diameter D of the top cross section is 220 The height h of the reduced diameter reaction section II The ratio is 0.005-0.3:1 independently, and the inner diameter D of the bottom cross section 210 The height h of the reduced diameter reaction section II The ratio is 0.015-0.25:1 independently, and the inner diameter of the bottom cross section D 210 and the inner diameter D of the top cross section 220 The ratio of each is independently greater than 1.2 and less than or equal to 10, more preferably 1.5 to 5; the diameter reduction reaction section h II The ratio of the height of the bottom end to the total height h of the reactor is 0.15:1 to 0.8:1, preferably 0.2:1 to 0.75:1. In one embodiment, the inner diameter D of the bottom cross section is 210 The ratio of the height h1 of the reduced diameter reaction section to the total height h of the reactor is 0.01:1 to 0.5:1, preferably 0.05:1 to 0.2; the ratio of the height h1 of the reduced diameter reaction section to the total height h of the reactor is 0.15:1 to 0.8:1, preferably 0.2:1 to 0.75:1, and the total height h1 of the reaction zone II is 0.15:1 to 0.8:1, preferably 0.2:1 to 0.75:1. II The ratio of the inner diameter D of the top cross section of the reduced diameter reaction section 100 to the total height h of the reactor is 0.15:1 to 0.8:1, preferably 0.2:1 to 0.75:1. 210 In one embodiment, the total height h of the reaction zone II is 0.2-5 meters, preferably 0.4-3 meters. II It may be about 2-50 meters, preferably about 5-40 meters, and more preferably about 8-20 meters.

[0073] In the catalytic cracking reactor of the present application, the reduced-diameter reaction section, especially the conical reaction section, has a large bottom space, which can effectively increase the catalyst density in the reactor, thereby greatly increasing the ratio of catalyst to reaction raw materials in the reactor, strengthening the primary cracking reaction of the raw materials, not only improving the reaction conversion rate, but also increasing the yield of light olefins; moreover, the reduced-diameter reaction section, especially the reduced-diameter structure of the conical reaction section, is conducive to accelerating the reaction oil and gas to leave the reaction zone, shortening the reaction time, and reducing catalyst backmixing, which is conducive to reducing the secondary conversion reaction of the light olefins generated by the primary reaction and improving the selectivity of light olefins.

[0074] In the catalytic cracking reactor provided herein, the reactor may be provided with one or more, for example, one, two or more, raw material feed ports, and the one or more raw material feed ports may be independently provided at the outlet end of the pre-elevation zone I, or at the bottom of the reaction zone II. Further preferably, the positions of the multiple raw material inlets are independently located at the same height or at different heights of the reaction zone II. Thus, raw materials of different properties can be fed separately at different raw material feed ports.

[0075] like Figure 1 As shown, the catalytic cracking reactor may include an outlet zone III. In one embodiment, the outlet zone III may be in the form of a hollow cylinder with a cross-sectional inner diameter and a height h III The ratio is 0.01-0.3:1, the height h of the outlet area III The ratio to the total height h of the reactor is 0.05: 1 to 0.5: 1, more preferably 0.1: 1 to 0.35: 1. In one embodiment, the inner diameter of the outlet zone III is 0.2-5 meters, preferably 0.4-3 meters.

[0076] As mentioned above, the inner diameter of the cross section at the top of reaction zone II is equal to or smaller than the inner diameter of the cross section of outlet zone III. In one embodiment, the inner diameter of the cross section at the top of reaction zone II is equal to the inner diameter of the cross section of outlet zone III.

[0077] In one embodiment, the inner diameter of the cross section at the top of reaction zone II is smaller than the inner diameter of the cross section of outlet zone III. In this case, reaction zone II and outlet zone III may be connected by a third transition section (not shown). The longitudinal section of the third transition section may be an isosceles trapezoid, and the outward inclination angle of the side of the isosceles trapezoid may be 5-85°, preferably 15-75°.

[0078] The outlet end of the outlet zone III may be open or directly connected to the inlet of an oil separation device such as a cyclone separator.

[0079] like Figure 2As shown, the regeneration device 1000 of the present application includes a coke generator 300 and a regenerator 400 , wherein the outlet of the coke generator 300 is in fluid communication with the inlet of the regenerator 400 , so that the material from the coke generator 300 can flow into the regenerator 400 .

[0080] In the present application, the coke generator 300 is provided with an inlet 306 for regenerated catalyst, an inlet 301 for oxygen-depleted gas, and an inlet 304 for fuel oil. The bottom of the coke generator 300 is connected to the bottom of the regenerator 400 via an external catalyst circulation pipe 303, allowing a portion of the high-temperature regenerated catalyst in the regenerator to flow into the coke generator to heat the regenerated catalyst from the reactor in the coke generator, thereby optimizing energy utilization.

[0081] In the present application, the coke generator 300 is a fast fluidized bed. In one embodiment, the coke generator 300 is a hollow cylindrical shape with an aspect ratio of 30:1 to 3:1.

[0082] In the present application, the independently provided catalyst inlet 306, the connection port for the external catalyst circulation pipe 303, the oxygen-depleted gas inlet 301, and the fuel oil inlet 304 are located at different heights within the coke maker 300. Preferably, the oxygen-depleted gas inlet 301, the connection port for the external catalyst circulation pipe 303, the catalyst inlet 306, and the fuel oil inlet 304 are provided in this order from bottom to top within the coke maker 300, and all are located at the bottom of the coke maker 300 (with a distance from the bottom of the coke maker no greater than 50% of the coke maker's height).

[0083] In the present application, one or more oxygen-depleted gas inlets 301 are provided at the bottom of the coke maker 300. In one embodiment, the oxygen-depleted gas inlets 301 are located at the bottom of the coke maker 300. Preferably, a first gas distributor 302 is provided at the bottom of the coke maker 300, so that the oxygen-depleted gas injected through the oxygen-depleted gas inlets 301 enters the coke maker 300 through the first gas distributor 302.

[0084] According to the present application, the first gas distributor 302 can be a primary air distributor known to those skilled in the art. For example, the primary air distributor can be a distribution plate or a distribution pipe. Preferably, the distribution pipe is an annular distribution pipe or a dendritic distribution pipe.

[0085] According to the present application, the oxygen-depleted gas injected into the coke generator 300 can be selected from oxygen, air, nitrogen, water vapor or a mixture thereof. Preferably, the oxygen content in the oxygen-depleted gas is 1 volume %-20 volume %, preferably, the oxygen content in the oxygen-depleted gas is 5 volume %-10 volume %.

[0086] In one embodiment, the connection port of the external catalyst circulation pipe 303 on the coke former 300 is arranged at the lower part of the coke former 300, preferably at a distance of 5% to 10% of the height of the coke former from the bottom of the coke former.

[0087] In the present application, the coke former 300 can be provided with one or more, for example one, two or more fuel oil inlets 304, which can each independently be arranged at the outlet end of the coke former or at the bottom of the coke former. Further preferably, the fuel oil inlets 304 are each independently arranged at the middle upstream of the coke former. Further preferably, the fuel oil inlets are each independently arranged at a distance of 20% to 50% of the height of the coke former from the bottom of the coke former. The fuel oil can include straight-run distillate oil or secondary processed distillate oil. Preferably, the secondary processed distillate oil can be selected from a mixture of one or more of catalytically cracked diesel oil, catalytically cracked slurry oil, coking gasoline, coking diesel oil and coking wax oil.

[0088] In the present application, a catalyst distribution plate 305 can be arranged at the position where the catalyst enters the bottom of the regenerator, for example at the outlet end of the coke former. According to the present application, the catalyst distribution plate can be of various types commonly used in industry, for example one or more of flat plate, arch, disc, ring and umbrella. The use of the catalyst distribution plate helps to make the catalyst contact with the oxygen-rich gas for coking reaction uniformly in the axial direction of the regenerator, improves the coking efficiency and reduces the occurrence of local hot spots in the catalyst bed.

[0089] By arranging the coke former 300, the injected fuel oil is mixed with the catalyst under the condition of low temperature and lean oxygen fluidization to form coke, and the catalyst with coke attached is passed through the coke former with the characteristics of a fast fluidized bed by back mixing, so that the coke is uniformly distributed on the catalyst and partially combusted, realizing the stepwise rise of the surface temperature of the catalyst.

[0090] In the present application, the regenerator 400 can adopt the existing common regenerator structure, only need to be provided with an opening at the bottom thereof, and the outlet of the coke former 300 is connected with the opening, that is, the outlet of the coke former 300 is in fluid communication with the inlet of the regenerator 400, so that the material from the coke former can flow into the regenerator.

[0091] The lower part of the regenerator 400 is also provided with a connection port for the external catalyst circulation pipe 303, so that a part of the regenerated catalyst in the regenerator can flow into the coke former for heating the spent catalyst from the reactor in the coke former, to realize the optimized use of energy.

[0092] The regenerator 400 is provided with an oxygen-rich gas inlet 401 for injecting oxygen-rich gas into the regenerator 400 for regeneration of the catalyst entering the regenerator. In one embodiment, the oxygen content of the oxygen-rich gas entering the regenerator is 21% to 100% by volume, and more preferably, the oxygen content of the oxygen-rich gas is 21% to 85% by volume. In the present application, the oxygen-rich gas injected into the regenerator can be air.

[0093] In one embodiment, a second gas distributor 402 is provided at the bottom of the regenerator, so that the oxygen-enriched gas injected through the oxygen-enriched gas inlet enters the regenerator through the second gas distributor. According to the present application, the second gas distributor 402 can be a primary air distributor well known to those skilled in the art. For example, the primary air distributor can be a distribution plate or a distribution pipe. Preferably, the distribution pipe is an annular distribution pipe or a dendritic distribution pipe.

[0094] In one embodiment, the regenerator 400 is fluidically connected to a gas-solid separation device 404, such that the regeneration flue gas generated by the regenerator is separated by the gas-solid separation device 404 and then introduced into an energy recovery system via a regeneration flue gas pipeline 405 for recycling. In this application, the gas-solid separation device can be any device familiar to those skilled in the art. For example, the gas-solid separation device can include a cyclone separator.

[0095] The regenerator 400 is also provided with a regenerated catalyst outlet 406 for sending the regenerated high-temperature regenerated catalyst out of the regenerator for use in the reaction cycle.

[0096] In the present application, the regenerator 400 and the coke generator 300 can be arranged coaxially or in parallel at different heights.

[0097] In this application, after the partially coked catalyst enters the regenerator, it undergoes sufficient charring in the presence of high-temperature, oxygen-rich gas, releasing heat and providing the necessary heat for the reaction. The equipment described in this application mitigates the charring environment on the catalyst, achieving a gradual temperature rise, and maximally protecting the catalyst's physical and chemical properties.

[0098] Figure 3 The catalytic cracking reaction-regeneration system including the catalytic cracking reactor 100 and the regeneration device 1000 of the present application is shown. Figure 3 As shown, the catalytic cracking reaction-regeneration system includes the above-mentioned catalytic cracking reactor 100 of the present application, an oil separation device 200, and a regeneration device 1000 (the regeneration device 1000 includes a coking device 300 and a regenerator 400).

[0099] The catalytic cracking reactor 100 is provided with a catalyst inlet 103 at the bottom, a raw material feed inlet 102 at the lower part, and an oil agent outlet 150 at the top.

[0100] The oil separation equipment 200 includes an oil separation device 204 for separating reaction products and catalyst from the oil from the catalytic cracking reactor 100. The oil separation device 204 is connected to the outlet of the catalytic cracking reactor. A settler 201 is used to collect the separated catalyst to be regenerated. The catalyst separated by the oil separation device 204 is allowed to settle and then enter the lower part of the settler. Fluidizing gas can be introduced into the lower part of the settler 201 through an inlet 202 to fluidize the catalyst in the lower part of the settler, facilitating the catalyst's flow through the regenerated inclined pipe 203 to the coker 300.

[0101] The coke generator 300 is connected to the lower part of the settler 201 through the to-be-generated inclined pipe 203 (via the catalyst inlet 306), so that the to-be-generated catalyst separated from the reactor enters the coke generator 300 and contacts with the fuel oil to generate a coke reaction.

[0102] The regenerator 400 is connected to the coke generator 300 via the catalyst distribution plate 305 , and is used to regenerate the coked catalyst from the coke generator 300 .

[0103] The regenerator 400 is also connected to the catalytic cracking reactor 100 via a regeneration inclined pipe 103 (via a catalyst outlet 406 ) so as to allow the regenerated catalyst regenerated by the regenerator 400 to circulate back to the catalytic cracking reactor 100 for reaction.

[0104] In the catalytic cracking reaction-regeneration 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 an oil separation device.

[0105] The reaction oil and gas (i.e., reaction products) separated by the oil agent separation device 204 are collected in a gas collection chamber 205 and then transported to a subsequent reaction product separation device (not shown) via pipeline 206 for separation. The reaction product separation device can 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, for separating the reaction products into components such as dry gas, liquefied gas, pyrolysis gasoline, pyrolysis diesel, and pyrolysis heavy oil according to the distillation range of the reaction products.

[0106] The regenerated catalyst separated by the oil-agent separation device 204 enters the lower part of the settler and is transported to the coker 300 through the regenerated inclined pipe 203. In the coker 300, the regenerated catalyst is partially burned and heated when it contacts the oxygen-depleted gas introduced through the pipeline 301 and the regenerated catalyst transported through the external catalyst circulation pipe 303. Then, it contacts the fuel oil transported through the fuel oil inlet 304 to cause a coking reaction, and is then transported to the regenerator 400 through the catalyst distribution plate 305.

[0107] In the regenerator 400, the coked catalyst is burned under the action of the oxygen-containing regeneration gas introduced through the oxygen-rich gas inlet 401 to obtain a regenerated catalyst, which is input into the reactor 100 through the regeneration inclined pipe 103; and the flue gas is discharged through the pipeline 405 into the energy recovery system.

[0108] In the catalytic cracking reaction-regeneration system provided herein, the oil-agent separation device, regenerator, other devices, reaction product separation device, etc. can all be devices familiar to those skilled in the art, and the connection between these devices can also be implemented in accordance with methods known in the art. For example, the oil-agent separation device may include a cyclone separator and an outlet rapid separator. In certain embodiments, the oil-agent separation device includes a settler arranged coaxially with the catalytic cracking reactor or arranged in parallel at a higher level.

[0109] The present application provides a catalytic cracking method, in which the reaction raw materials and the catalyst are contacted and reacted in the catalytic cracking reaction-regeneration system described above, comprising the following steps:

[0110] The preheated reaction raw materials enter the pre-lifting zone and reaction zone of the reactor in turn, where they come into contact with and react with the regenerated catalyst from the regenerator. The reaction oil and gas and the regenerated catalyst enter the cyclone separator through the outlet zone for gas-solid separation. The separated reaction oil and gas are drawn out of the device for further separation to obtain ethylene, propylene, C4 hydrocarbon fractions and cracked gasoline rich in light aromatics. The separated regenerated catalyst enters the lower part of the settler and enters the coker through the regeneration riser.

[0111] Injecting oxygen-depleted gas into the coking device through the oxygen-depleted gas inlet, the gas contacts the regenerated catalyst from the regenerator and the catalyst to be regenerated from the reactor, causing the catalyst to heat up and undergo a partial coking reaction, which causes the catalyst to move upward. The catalyst then contacts a mixture of an atomizing medium and combustion oil injected through the fuel oil inlet, causing a coking reaction and a partial coking reaction to occur, thereby obtaining a catalyst with a portion of coke.

[0112] The catalyst with some coke enters the regenerator and comes into contact with the oxygen-rich gas injected into the regenerator through the oxygen-rich gas inlet, undergoing a complete combustion reaction. The regenerated catalyst with restored activity is returned to the reactor for recycling.

[0113] The catalytic cracking reaction-regeneration system and method provided in the present application are applicable to the catalytic cracking reaction of various raw materials, such as light hydrocarbons or light distillate oils, oxygenated hydrocarbons, shale oil, hydrorefined wax oil, hydrotreated modified wax oil, hydrocracking tail oil or a mixture of one or more of the above raw materials to produce light olefins by catalytic cracking, especially the reaction of catalytic cracking of light hydrocarbons or light distillate oils to produce light olefins.

[0114] For example, the light hydrocarbons or light distillate oils can be gaseous hydrocarbons, petroleum hydrocarbons with a distillation range of 25 to 360° C., oxygen-containing compounds, distillates of biomass or waste plastics; the gaseous hydrocarbons can be selected from a mixture of one or more of saturated liquefied gas, unsaturated liquefied gas, and C4 fractions; the petroleum hydrocarbons can be selected from a mixture of one or more of primary processed straight-run naphtha, straight-run kerosene, and straight-run diesel; or a mixed oil of one or more of secondary processed topped oil, raffinate oil, hydrocracked light naphtha, pentane oil, coker gasoline, Fischer-Tropsch synthetic oil, catalytic cracking light gasoline, hydrogenated gasoline, and hydrogenated diesel.

[0115] In one embodiment, the reaction raw material is selected from C4-C20 light crude oil.

[0116] In one embodiment, the reaction conditions in the reaction zone of the reactor include: a reaction temperature of 510-750°C, a reaction time of 0.5-10 seconds, a catalyst-oil weight ratio of 10:1 to 50:1, and a fluidizing gas to coke raw material weight ratio of 0.05:1 to 2.0:1.

[0117] In one embodiment, the reaction conditions in the reaction zone of the reactor include: a reaction temperature of 550-700° C., a reaction time of 1-5 seconds, a catalyst-to-oil weight ratio of 20:1 to 40:1, and a fluidizing gas to coke feed weight ratio of 0.2:1 to 0.8:1. The fluidizing gas may be nitrogen, water vapor, or a mixture thereof.

[0118] In one embodiment, the catalyst comprises, on a dry basis and based on the dry weight of the catalyst, 1-50 wt%, preferably 5-45 wt%, more preferably 10-40 wt% zeolite; 5-99 wt%, preferably 10-80 wt%, more preferably 20-70 wt% inorganic oxide; and 0-70 wt%, preferably 5-60 wt%, more preferably 10-50 wt% clay.

[0119] In one embodiment, the linear speed of the coke generator is 1.2 m / s to 2.2 m / s, and the oxygen content in the oxygen-depleted gas is 1% to 20%. More preferably, the oxygen content in the oxygen-depleted gas is 5% to 10%.

[0120] In one embodiment, the atomizing medium is nitrogen and the mass ratio of the atomizing medium to the fuel oil is 1 : 1 to 1 : 100. In one embodiment, the fuel oil comprises straight run distillate oil or secondary processed distillate oil. Preferably, the secondary processed distillate oil can be selected from a mixture of one or more of catalytically cracked diesel oil, coking gasoline, coking diesel oil and coking wax oil.

[0121] In one embodiment, the outlet temperature of the coke former is 550-650°C.

[0122] In one embodiment, the oxygen content in the oxygen-rich gas of the regenerator is 21 vol% to 100 vol%, further preferably, the oxygen content in the oxygen-rich gas is 21 vol% to 85 vol%.

[0123] In one embodiment, the temperature in the regenerator is 600-800°C, preferably 650-750°C; the gas superficial linear velocity is 0.2-1.0 m / s, preferably 0.3-0.8 m / s; and the average residence time of the catalyst is 0.5-10 minutes, preferably 1-5 minutes.

[0124] In one embodiment, the zeolite comprises a medium pore zeolite selected from the group consisting of ZSM series zeolite, ZRP zeolite, and any combination thereof; and optionally a large pore zeolite selected from the group consisting of rare earth Y-type zeolite, rare earth hydrogen Y-type zeolite, ultra-stable Y-type zeolite and high-silica Y-type zeolite, and any combination thereof.

[0125] In one embodiment, the medium pore zeolite accounts for 10-100 wt%, preferably 50-90 wt% of the total weight of the zeolite, on a dry basis.

[0126] In the present application, the medium pore zeolite and the large pore zeolite are defined in accordance with the conventional definition in the art, i.e. the average pore diameter of the medium pore zeolite is about 0.5-0.6 nm, and the average pore diameter of the large pore zeolite is about 0.7-1.0 nm.

[0127] As an example, the large-pore zeolite can be selected from one or more of rare earth Y (REY) type zeolite, rare earth hydrogen Y (REHY) type zeolite, ultra-stable Y type zeolite obtained by different methods, and high-silicon Y type zeolite. The medium-pore zeolite can be selected from zeolites with MFI structure, such as ZSM series zeolites and / or ZRP zeolite. Optionally, the above-mentioned medium-pore zeolite can also be modified with non-metallic elements such as phosphorus and / or transition metal elements such as iron, cobalt, nickel, etc. For a more detailed description of ZRP zeolite, please refer to US Patent US5,232,675A. The ZSM series zeolite is preferably selected from a mixture of one or more of ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48 and other similar structure zeolites. For a more detailed description of ZSM-5, please refer to US Patent US3,702,886A.

[0128] According to the present application, the inorganic oxide as a binder is preferably silicon dioxide (SiO2) and / or di-aluminum trioxide (Al2O3). The clay as a matrix (i.e. carrier) is preferably kaolin and / or halloysite.

[0129] With the catalytic cracking reaction-regeneration system and method of the present application, chemical raw materials such as ethylene and propylene can be efficiently produced from light petroleum hydrocarbons, helping refineries to transform, develop and extend from oil refining to chemical raw material production, solving the problem of shortage of petrochemical raw materials, and improving the economic benefits of refineries.

[0130] The present application will be further described in conjunction with the preferred embodiments shown in the accompanying drawings, but the present application is not limited thereto.

[0131] Figure 1 A preferred embodiment of the catalytic cracking reactor of the present application is given, wherein the catalytic cracking reactor 1 comprises, from bottom to top, a pre-lifting zone I, a reaction zone II, and an outlet zone III in sequence. The reaction zone II comprises a reduced-diameter reaction section in the form of a hollow truncated cone with an isosceles trapezoidal longitudinal section. The pre-lifting zone I is provided with a catalyst inlet 103 at the lower part, and a raw material inlet 102 at the upper part of the pre-lifting zone I and / or the bottom of the reaction zone II. The cross-sectional inner diameter of the bottom end of the reaction zone II is greater than the inner diameter of the pre-lifting zone I, and the cross-sectional inner diameter of the top end is equal to the inner diameter of the pre-lifting zone I and the inner diameter of the outlet zone III.

[0132] Figure 2A preferred embodiment of the regeneration equipment of the present application is provided, comprising a coke generator 300 and a regenerator 400. The coke generator 300 has an oxygen-depleted gas inlet 301 and a gas distribution plate 302 at its bottom. A catalyst inlet 306 for regeneration and a connection port for an external catalyst circulation pipe 303 are provided on the lower sidewall of the coke generator. A fuel oil inlet 304 is provided midway and upstream of the coke generator. A main air distributor 402 is provided at the bottom of the regenerator, and one or more, for example, one, two, or more, main air inlets 401 are provided on the lower sidewall.

[0133] Figure 3 Shows the inclusion Figure 1 Catalytic cracking reactor 1000 and Figure 2 A catalytic cracking reaction-regeneration system of a regeneration device 1000 (including a coke generator 300 and a regenerator 400).

[0134] A pre-lifting medium, which can be dry gas, steam, or a mixture thereof, enters the catalytic cracking reactor 100 from the bottom of pre-lifting zone I via pipeline 101. Hot regenerated catalyst from the regeneration inclined tube 103 enters the lower portion of pre-lifting zone I and moves upward under the lifting action of the pre-lifting medium. Reactant feedstock, such as preheated light crude oil and atomized steam, is injected into the upstream portion of pre-lifting zone I and / or the bottom portion of reaction zone II via feed line 102. It mixes with the catalyst already in the catalytic cracking reactor and undergoes a catalytic cracking reaction as it passes upward through reaction zone II. The reaction products flow upward, with the coked catalyst and reaction oil and gas entering an oil-agent separation device 204, such as a cyclone separator, through outlet zone III for gas-solid separation. The separated reaction oil and gas exit the device through a gas collection chamber 205 and a large oil and gas pipe 206, entering a subsequent separation system. The separated regenerated catalyst, which contains coke, enters the lower portion of the settler 200 and, via the regeneration inclined tube 203, enters the coke generator 300.

[0135] Oxygen-depleted gas enters the coker 300 from the bottom via the oxygen-depleted inlet 301 and the gas distributor 302. The oxygen-depleted gas can be oxygen, air, nitrogen, water vapor, or a mixture thereof. High-temperature regenerated catalyst from the external catalyst circulation pipe 303 enters the lower portion of the coker 300, mixes with the oxygen-depleted gas, and moves upward, where it contacts the regenerated catalyst from the regenerated catalyst inlet 203 and undergoes a partial charring reaction. The reactant stream continues upward, contacting the supplemental fuel oil from the fuel oil inlet 304 and undergoing a coking reaction and a partial charring reaction. The charred catalyst flows upward through the catalyst distributor 305 and enters the regenerator 400. It contacts the oxygen-rich gas injected via the oxygen-rich gas inlet 401 and the main air distributor 402, undergoing a complete combustion reaction and thoroughly releasing heat. The regenerated catalyst is then transported out of the regenerator via the regenerated catalyst outlet 406 for use in the reaction cycle. The regenerated flue gas is separated from the entrained catalyst by the cyclone separator 404 and enters the energy recovery system via pipeline 405.

[0136] Example

[0137] The following examples will further illustrate the present application, but are not intended to limit the present application.

[0138] The raw oil used in the following examples and comparative examples is straight-run naphtha, the properties of which are shown in Table 1. The catalyst used is a commercial catalytic cracking catalyst purchased from the Catalyst Branch of Sinopec, with the trade name NCC.

[0139] Example 1

[0140] Using the feedstock oil and NCC catalyst shown in Table 1, Figure 3 The experiment was carried out on the pilot plant shown in FIG. 1 , wherein the structure of the reactor used is as follows:

[0141] The total height of the reactor is 10 meters, of which the pre-lifting zone is 2 meters and the inner diameter is 0.2 meters; the reaction zone is 5 meters high, the inner diameter of the top cross section is 0.2 meters, and the inner diameter of the bottom cross section is 0.3 meters; the outlet zone is 3 meters high and has an inner diameter of 0.2 meters.

[0142] The coke generator has an inner diameter of 0.3 meters and a height of 2 meters. The fuel oil inlet 304 of the coke generator is located 30% of the height from the bottom of the coke generator. The coke generator outlet is directly connected to the bottom opening of the regenerator and is equipped with a catalyst distributor at the outlet.

[0143] The hot regenerated catalyst from the regenerated catalyst slope 103 enters the lower part of the pre-lifting zone I and moves upward under the lifting action of the pre-lifting medium. The preheated feedstock oil and atomized steam are injected into the upper part of the pre-lifting zone I through the feed line 102, mixed with the existing catalyst in the catalytic cracking reactor, and subjected to catalytic cracking reaction in the process of passing through the reaction zone II from bottom to top. The obtained catalyst with coke and reaction oil gas enter the oil catalyst separation device 204 such as a cyclone separator through the outlet zone III, and are subjected to gas-solid separation. The separated reaction oil gas is introduced into the subsequent separation system through the gas collecting chamber 205 and the large oil gas pipe 206. The separated catalyst with coke enters the lower part of the settler 200 and then enters the coke former 300 through the spent catalyst slope 203.

[0144] The mixture of nitrogen with an oxygen content of 5% and air is introduced into the bottom of the coke former 300, mixed with the regenerated catalyst and the spent catalyst, and moves upward, so as to heat the spent catalyst and make the spent catalyst partially combust the coke; the fuel oil atomized by nitrogen is injected into the coke former, mixed with the stream in the coke former, and subjected to coking reaction and a small amount of burning reaction; the catalyst with coke enters the regenerator, is contacted with air, and is subjected to complete combustion reaction. The regenerated catalyst returns to the reactor 100 through the regenerated catalyst slope 103 for recycling. The regenerated flue gas enters the energy recovery system through the pipeline 405.

[0145] A temperature measuring point is arranged at the outlet of the coke former to measure the outlet temperature of the coke former; two temperature measuring points are arranged at the same height of 40% of the axial height of the regenerator, close to the wall of the regenerator (the angle relative to the axial direction is 180 degrees), to measure the middle temperature at different positions at the same height; a temperature measuring point is arranged at the top of the regenerator to measure the upper temperature of the regenerator.

[0146] The operating conditions and product distribution are listed in Table 2. As can be seen from Table 2, the ethylene yield of the present embodiment reaches 25.51% by weight, the propylene yield reaches 24.26% by weight, and the methane and coke yields are 10.07% by weight and 3.71% by weight, respectively. The temperatures at different positions in the middle of the regenerator are 687°C and 681°C, respectively, and the radial temperature difference is only 6°C. The upper temperature of the regenerator is 695°C, and the axial temperature difference is about 10°C.

[0147] Comparative Example 1

[0148] Tests were conducted on a medium-sized unit using the feedstock and NCC catalyst shown in Table 1. The reactor was a conventional riser reactor. Preheated feedstock entered the lower portion of the riser reaction zone, where it came into contact with the catalytic cracking catalyst for a catalytic cracking reaction. The post-reaction stream entered the subsequent oil-agent separation unit and product separation equipment. The separated regenerated catalyst entered the lower portion of the regenerator, where it came into contact with air distributed by the primary air distributor, causing a charring reaction. Fuel oil was then injected into the dense catalyst bed, where it charred upon contact with the high-temperature air, releasing heat. The regenerated catalyst was then returned to the reactor for recycling. The operating conditions and product distribution are listed in Table 2.

[0149] At the same height of the regenerator, which is 40% of the axial height of the regenerator from the bottom, two temperature measuring points are set close to the regenerator wall (the angles of the two relative to the axial direction are 180 degrees), and the middle temperatures at different positions at the same height are measured; a temperature measuring point is set at the top of the regenerator to measure the upper temperature of the regenerator.

[0150] As can be seen from the results in Table 2, the ethylene yield of this comparative example was only 18.09% by weight, the propylene yield was only 20.14% by weight, and the methane and coke yields were 12.91% and 3.89% by weight, respectively. The temperatures at different locations in the middle of the regenerator were 668°C and 725°C, respectively, with a radial temperature difference of only 57°C. The temperature at the top of the regenerator was 737°C, with a large axial temperature difference.

[0151] The results of the above examples and comparative examples demonstrate that the catalytic cracking reactor and system of the present application significantly improves ethylene and propylene yields while reducing methane and coke yields when performing naphtha catalytic cracking reactions. The coke combustion environment within the regenerator is moderate and stable, and the radial and axial catalyst temperatures help maintain the physical and chemical properties of the catalyst.

[0152] The preferred embodiments of the present application are described in detail above. However, the present application is not limited to the specific details of the above embodiments. Within the technical concept of the present application, various simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the scope of protection of the present application.

[0153] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner unless there is any contradiction. In order to avoid unnecessary repetition, this application will not further describe various possible combinations.

[0154] In addition, the various implementation methods of the present application can be arbitrarily combined, as long as they do not violate the concept of the present application, they should also be regarded as the content of the invention of the present application.

[0155] Table 1 Properties of the straight-run naphtha used

[0156] <![CDATA[密度(20℃) / (克 / 厘米 3 )]]> 0.7525 Carbon content / weight% 87.47 Hydrogen content / weight% 14.53 Sulfur content / (mg / L) 140 Nitrogen content / (mg / L) 1.2 Distillation range / ℃ 10% by volume 90.9 30% by volume 121.7 50% by volume 145.8 70% by volume 167.3 95% by volume 197.5 Hydrocarbon composition / weight% Alkanes 58.30 Olefins 0 Cycloalkanes 30.18 Aromatics 11.52

[0157] Table 2 Comparison of reaction results between Example 1-2 and Comparative Example 1

[0158] Example 1 Comparative Example 1 Catalytic cracking reactor conditions Reactor outlet temperature, °C 675 675 Reaction time, seconds 2.0 2.5 Weight ratio of fluidizing gas to coke raw materials 0.3 0.3 Agent-oil weight ratio 30 30 Fuel oil usage as a percentage of feed, % 6 6 Oxygen content in oxygen-depleted gas, weight % 5 / Regenerator conditions Regenerator middle temperature 1, ℃ 687 725 Regenerator middle temperature 2, ℃ 681 668 Regenerator upper temperature, ℃ 695 737 Product distribution, weight % H2~C2 40.19 39.48 Of which methane 10.07 12.91 Of which ethylene 25.51 18.09 C3~C4 38.23 36.5 Of which propylene 24.26 20.14 gasoline 15.58 17.21 fuel oil 2.29 2.92 coke 3.71 3.89 total 100 100

Claims

1. A catalytic cracking reaction-regeneration system comprising: A catalytic cracking reactor, wherein the catalytic cracking reactor comprises, from bottom to top,: Pre-lifting area; A reaction zone, the reaction zone comprising at least one reduced-diameter reaction section, the reduced-diameter reaction section being in the form of a hollow truncated cone, the longitudinal section of which is an isosceles trapezoid; and export zone; The pre-lifting zone is connected to the bottom end of the reaction zone, the top end of the reaction zone is connected to the outlet zone, and at least one raw material feed port is provided on the pre-lifting zone and / or at the bottom of the reaction zone; The inner diameter of the cross section of the bottom end of the reaction zone is greater than or equal to the inner diameter of the cross section of the pre-lifting zone, and the inner diameter of the cross section of the top end is equal to or smaller than the inner diameter of the cross section of the pre-lifting zone and the inner diameter of the cross section of the outlet zone; a regenerated catalyst inlet is provided at the bottom of the reaction zone and / or the pre-lifting zone; An oil-agent separation device is configured to communicate with the outlet area of ​​the catalytic cracking reactor so that the reaction oil gas and catalyst from the catalytic cracking reactor are separated in the oil-agent separation device, and an outlet for the catalyst to be regenerated is provided on the oil-agent separation device; wherein the oil-agent separation device includes a settler for collecting the separated catalyst to be regenerated, and the lower portion of the settler has an inlet for introducing a fluidizing gas, the fluidizing gas being used to fluidize the catalyst in the lower portion of the settler, so that the catalyst can flow into the coker through the outlet for the catalyst to be regenerated; A regeneration device, comprising a coke generator and a regenerator, wherein the outlet of the coke generator is in fluid communication with the inlet of the regenerator so that material from the coke generator can flow into the regenerator; and the bottom of the coke generator is in fluid communication with the bottom of the regenerator via an external catalyst circulation pipe; The coke maker is provided with an inlet for the catalyst to be generated, a connection port for an external catalyst circulation pipe, an oxygen-depleted gas inlet, and a fuel oil inlet in order from bottom to top; the inlet for the catalyst to be generated of the coke maker is connected to the outlet for the catalyst to be generated of the oil separation device, so that the catalyst to be generated enters the coke maker; the coke maker is a fast fluidized bed and is hollow cylindrical with an aspect ratio of 30:1 to 3:1; The regenerator is provided with an oxygen-rich gas inlet and a regenerated catalyst outlet, wherein the regenerated catalyst outlet of the regenerator is connected to the regenerated catalyst inlet, so that the regenerated catalyst is circulated back to the catalytic cracking reactor.

2. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: in, The ratio of the inner diameter of the bottom cross-section of the reaction zone to the total height of the catalytic cracking reactor is 0.01:1 to 0.5:1; the ratio of the total height of the reaction zone to the total height of the catalytic cracking reactor is 0.15:1 to 0.8:

1.

3. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: The reaction zone includes 1 to 3 diameter-reducing reaction sections.

4. The catalytic cracking reaction-regeneration system according to claim 3, characterized in that: The ratio of the inner diameter of the top cross-section of the reaction zone to the height of the reduced diameter reaction section is independently 0.005-0.3:1, the ratio of the inner diameter of the bottom cross-section to the height of the reduced diameter reaction section is independently 0.015-0.25:1, and the ratio of the inner diameter of the bottom cross-section to the inner diameter of the top cross-section is independently greater than 1.2 and less than or equal to 10; the ratio of the height of the reduced diameter reaction section to the total height of the catalytic cracking reactor is independently 0.15:1 to 0.8:

1.

5. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: The ratio of the inner diameter to the height of the pre-lifting zone is 0.02-0.4:1; and the ratio of the height of the pre-lifting zone to the total height of the catalytic cracking reactor is 0.01:1 to 0.2:

1.

6. The catalytic cracking reaction-regeneration system according to claim 5, characterized in that: The pre-lifting zone is connected to the reaction zone by a first connecting section, the longitudinal section of the first connecting section is an isosceles trapezoid, and the outward inclination angle α of the side of the isosceles trapezoid is 5-85 o .

7. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: The ratio of the inner diameter of the cross section of the outlet zone to the height is 0.01-0.3:1, and the ratio of the height of the outlet zone to the total height of the catalytic cracking reactor is 0.05:1 to 0.5:

1.

8. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: The distance between the connection port of the external catalyst circulation pipe on the coke generator and the bottom of the coke generator is 5% to 10% of the height of the coke generator; The distance between the fuel oil inlet and the bottom of the coke generator is independently 20% to 50% of the height of the coke generator.

9. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: A first gas distributor is provided at the bottom of the coke generator, so that the oxygen-depleted gas injected through the oxygen-depleted gas inlet enters the coke generator through the first gas distributor; A catalyst distribution plate is provided at the outlet of the coking device, so that the catalyst passing through the coking device enters the regenerator after passing through the catalyst distribution plate.

10. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: The coke generator is in a hollow cylindrical shape, and its length-to-diameter ratio is 30:1 to 3:

1.

11. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: The bottom of the regenerator is provided with an opening, and the outlet of the coke generator is connected to the regenerator through the opening.

12. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that: The oil agent separation equipment includes a cyclone separator, which is connected to the outlet of the catalytic cracking reactor. and a settler arranged coaxially with the catalytic cracking reactor or arranged in parallel at different heights.

13. A catalytic cracking method, carried out in the catalytic cracking reaction-regeneration system according to any one of claims 1 to 12, comprising the following steps: The preheated reaction raw materials enter the pre-lifting zone and reaction zone of the catalytic cracking reactor in turn, contacting and reacting with the regenerated catalyst from the regenerator. The reaction oil gas and the regenerated catalyst enter the oil agent separation equipment through the outlet zone for gas-solid separation. The separated reaction oil gas is led out of the device for further separation to obtain ethylene, propylene, C4 hydrocarbon fraction and cracked gasoline rich in light aromatics; the separated regenerated catalyst enters the coker through the regeneration riser; Injecting oxygen-depleted gas into the coking device through the oxygen-depleted gas inlet, the gas contacts the regenerated catalyst from the regenerator and the catalyst to be regenerated from the catalytic cracking reactor, causing the catalyst to heat up and undergo a partial coking reaction, which causes the catalyst to move upward, and then contact the mixture of the atomizing medium and the combustion oil injected through the fuel oil inlet, causing a coking reaction and a partial coking reaction to occur, thereby obtaining a catalyst with a portion of coke; The catalyst with some coke enters the regenerator and comes into contact with the oxygen-rich gas injected into the regenerator through the oxygen-rich gas inlet, undergoing a complete combustion reaction. The regenerated catalyst with restored activity is returned to the catalytic cracking reactor for recycling.

14. The catalytic cracking method according to claim 13, wherein: The reaction raw materials are selected from C4-C20 light crude oil.

15. The catalytic cracking method according to claim 13, wherein: The reaction conditions in the reaction zone include: a reaction temperature of 510-750° C.; a reaction time of 0.5-10 seconds; a catalyst-oil weight ratio of 10:1 to 50:1; and a fluidizing gas to coke raw material weight ratio of 0.05:1 to 2.0:

1.

16. The catalytic cracking method according to claim 15, wherein: The reaction temperature is 550-700°C.

17. The catalytic cracking method according to claim 15, wherein: The reaction time is 1-5 seconds.

18. The catalytic cracking method according to claim 15, wherein: The agent-oil weight ratio is 20:1 to 40:

1.

19. The catalytic cracking method according to claim 15, wherein: The weight ratio of the fluidizing gas to the coking raw material is 0.2:1 to 0.8:

1.

20. The catalytic cracking method according to claim 13, wherein: The linear speed of the coke generator is 1.2 m / s to 2.2 m / s, and the oxygen content in the oxygen-depleted gas is 1% to 20% by volume; The oxygen content in the oxygen-rich gas of the regenerator is 21 volume % to 100 volume %.

21. The catalytic cracking method according to claim 20, wherein: The oxygen content in the oxygen-depleted gas is 5% to 10% by volume.

22. The catalytic cracking method according to claim 20, wherein: The oxygen content in the oxygen-rich gas is 21 volume % to 85 volume %.

23. The catalytic cracking method according to claim 13, wherein: The atomizing medium is nitrogen, and the mass ratio of the atomizing medium to the combustion oil is 1:1 to 1:100.

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