CN216946880U

CN216946880U - Catalytic cracking reactor and catalytic cracking system

Info

Publication number: CN216946880U
Application number: CN202123027053.7U
Authority: CN
Inventors: 魏晓丽; 张执刚; 龚剑洪
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2021-12-03
Filing date: 2021-12-03
Publication date: 2022-07-12
Anticipated expiration: 2031-12-03

Abstract

The application relates to a catalytic cracking reactor and catalytic cracking system, this catalytic cracking reactor from the bottom up includes in proper order: an optional pre-lift zone, a reaction zone comprising at least one reduced diameter reaction section, and an exit zone. By adopting the catalytic cracking reactor and the catalytic cracking system, chemical raw materials such as ethylene and propylene can be efficiently produced from light petroleum hydrocarbon, and the transformation, development and extension of refinery from oil refining to chemical raw material production are assisted, so that the problem of petrochemical raw material shortage is solved, and the economic benefit of the refinery is improved. When the reactor and the system are used for catalytic cracking reaction, the contact efficiency of raw materials and a catalyst is high, the catalytic reaction selectivity is good, the yield of high value-added products such as ethylene and propylene is high, and the yield of byproducts such as methane is low.

Description

Catalytic cracking reactor and catalytic cracking system

Technical Field

The application relates to the field of petrochemical industry, in particular to a catalytic cracking reactor and a catalytic cracking system.

Background

Ethylene and propylene are the most basic raw materials of petrochemical industry and the basis for producing various important organic chemical products. The scale, yield and technical level of production of ethylene and propylene are important marks for measuring the development level of the national petrochemical industry. Although the capacity and the yield of ethylene are the second place in the world in China and the capacity and the yield of propylene are the first place in the world, the demand of national economic development and improvement of the living standard of people in China cannot be met. In 2020, the equivalent requirements of ethylene and propylene in China are 5863 ten thousand tons and 4750 ten thousand tons respectively, the self-sufficiency rates of the ethylene and the propylene are about 51.4 percent and 79.9 percent respectively according to the equivalent requirements, and the olefin products still have insufficient production requirements. At present, light hydrocarbon steam cracking such as naphtha is still the main production technology of ethylene and propylene, and in order to reach the required temperature of schizolysis, the pyrolysis furnace all adopts fossil fuel to heat the boiler tube, makes the steam cracking furnace become the main emission source of carbon dioxide, the energy consumption is high, and product selectivity is poor, has a large amount of methane formation in the product. In view of this, researchers have been developing technologies for producing olefins by catalytic cracking of light hydrocarbons such as naphtha.

CN201510296090.8 discloses a naphtha conversion method, which combines naphtha catalytic cracking with low-carbon alkane steam cracking and high-carbon alkane and high-carbon olefin catalytic cracking to prepare low-carbon olefin, light aromatic hydrocarbon and high-octane gasoline. Since most of the reactants are converted in the catalytic cracking at a lower temperature, the energy consumption can be reduced as a whole.

CN201910080462.1 discloses a raw material conversion device containing naphtha, which comprises a step of reacting raw materials containing naphtha in a fast fluidized bed reactor to obtain product gas and a catalyst to be regenerated; then part of the stripped catalyst to be regenerated is supplied to the fast fluidized bed reactor, and part of the stripped catalyst to be regenerated is input to the regenerator. The device solves the technical problems of reducing the influence of thermal cracking reaction in the naphtha catalytic cracking technology and reducing the yield of methane in products.

CN 201811440380.5 discloses a process method for preparing propylene and co-producing aromatic hydrocarbon by low-temperature catalytic reaction using naphtha or light hydrocarbon as raw material. Raw material naphtha or light hydrocarbon enters a fixed bed reactor after being subjected to heat exchange by a heat exchanger and/or heated by a heating furnace, low-temperature catalytic reaction is carried out under the action of a specific catalyst, ethylene propylene, C-V hydrocarbon and byproduct aromatic hydrocarbons such as toluene and xylene are obtained after reaction products pass through a separation system, and a part of C-V hydrocarbon is circularly returned to the reactor.

CN201910201885.4 discloses a combined reactor for preparing olefin by alkane dehydrogenation and hydrocarbon catalytic cracking, the disclosed reaction device for preparing olefin by alkane catalytic dehydrogenation cracking comprises a reactor for catalytic dehydrogenation cracking and a reactor settling section, the reactor settling section is positioned at the upper part of the reactor, wherein the reactor comprises a dehydrogenation reaction section and a cracking reaction section, the dehydrogenation reaction section is positioned below the cracking reaction section, and one end of a catalyst regeneration inclined tube is connected with the dehydrogenation reaction section. The method is beneficial to dehydrogenation reaction and catalytic cracking reaction.

Compared with steam cracking, the fixed bed catalytic cracking of naphtha has the characteristic of low reaction temperature, but the conversion rate of the naphtha to low-carbon alkane is low. Naphtha catalytic cracking and steam cracking are combined, the ethylene yield can be improved to a certain extent, and the problem of carbon emission still exists. In combination with alkane dehydrogenation, there is a potential technical route, but the mechanism by which dehydrogenation and cracking complement catalyst and process technology is still being explored.

Naphtha and other light raw materials are small in molecules, high in reaction activation energy and high in reaction temperature, so that the yield of a byproduct methane is high, the catalytic cracking reaction heat is large, the heat required in the reaction aspect is large, and coke generated by self cracking cannot meet the self heat balance requirement of a reaction-regeneration system. The coke formation of light hydrocarbon catalytic cracking reaction such as naphtha is low, and a large amount of external fuel oil is needed. Because the catalytic cracking adopts the catalyst with the molecular sieve as the active component, the molecular sieve framework aluminum is gradually removed due to the local high temperature generated by the combustion of the fuel oil in the regenerator, and the activity of the catalyst is gradually reduced, thereby leading the further conversion rate of reactants to be reduced. Therefore, the catalytic cracking technology of light raw materials such as naphtha needs to be continuously advanced and developed, and higher reaction conversion rate and reaction selectivity are sought. The above prior art proposes a method and a catalyst for converting a petroleum hydrocarbon feedstock into a low-carbon olefin through a catalytic cracking reaction process, but fails to solve the problems of insufficient reaction heat and high methane yield in a cracking process of a light feedstock.

SUMMERY OF THE UTILITY MODEL

The application aims to provide a catalytic cracking reactor, a catalytic cracking system and a catalytic cracking method, which are used for improving the reaction selectivity of the light raw material catalytic cracking for producing ethylene and propylene, reducing the yield of methane and solving the problem of insufficient heat in the reaction process of the light raw material catalytic cracking.

The application provides a catalytic cracking reactor, a serial communication port, catalytic cracking reactor from the bottom up includes in proper order:

optionally a pre-lift zone,

the reaction zone comprises at least one diameter-reducing reaction section, the diameter-reducing reaction section is a hollow cylinder with a roughly circular cross section and open bottom and top ends, and the inner diameter of the diameter-reducing reaction section is continuously or discontinuously reduced from bottom to top; and

the outlet area is provided with a plurality of outlet areas,

wherein the optional pre-lifting area is communicated with the bottom end of the reaction area, the top end of the reaction area is communicated with the outlet area, and at least one raw material feeding hole is arranged on the optional pre-lifting area and/or the bottom of the reaction area;

the cross-sectional inner diameter of the bottom end of the reaction zone is greater than or equal to the cross-sectional inner diameter of the optional pre-lift zone, 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;

one or more reaction guiding agent inlets are arranged at the downstream of the reaction zone, and the distance between the one or more reaction guiding agent inlets and the outlet end of the reaction zone is 0-20% of the total height of the reaction zone.

In one embodiment, the ratio of the internal diameter of the bottom cross-section of the reaction zone 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 was 0.15: 1 to 0.8: 1.

in one embodiment, the reaction zone comprises 1 to 3 reduced diameter reaction sections.

In one embodiment, the diameter-reducing reaction section is in the form of a hollow truncated cone with a longitudinal section in the form of an isosceles trapezoid; the ratio of the inner diameter of the top end cross section to the height of the reducing reaction section is respectively and independently 0.005-0.3: 1, the ratio of the inner diameter of the cross section of the bottom end to the height of the diameter-reduced reaction section is respectively and independently 0.015-0.25: 1, the ratio of the bottom end cross section inner diameter to the top end cross section inner diameter is respectively and independently more than 1.2 and less than or equal to 10; the ratio of the height of the diameter-reducing reaction section to the total height of the reactor is respectively and independently 0.15: 1 to 0.8: 1.

in one embodiment, the internal diameter of the top end cross-section of the reduced diameter reaction section is each independently from 0.2 to 5 meters.

In one embodiment, wherein the ratio of the inner diameter to the height of the pre-lift zone is from 0.02 to 0.4: 1; the ratio of its height to the total height of the reactor was 0.01: 1 to 0.2: 1.

in one embodiment, the internal diameter of the pre-lift zone is from 0.2 to 5 meters.

In one embodiment, 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 camber angle α of the side of the isosceles trapezoid is 5-85 °.

In one embodiment, the outlet zone has a cross-sectional inner diameter to height ratio of 0.01 to 0.3: 1, the ratio of the height of the outlet zone to the total reactor height being 0.05: 1 to 0.5: 1.

in one embodiment, the cross-sectional inner diameter of the outlet zone is from 0.2 to 5 meters.

The present application further provides a catalytic cracking system, the catalytic cracking system includes catalytic cracking reaction unit, finish separator, steam stripping device, optional reaction product separator, and regenerator, its characterized in that, catalytic cracking reaction unit includes one or more catalytic cracking reactors of the present application.

In one embodiment, at least one fuel oil feed is provided in the lower part of the stripping unit and/or in the connecting line of the stripping unit and the regenerator.

In one embodiment, at least one said fuel oil feed inlet is provided in a lower portion of said stripping apparatus,

the fuel oil inlets are each independently spaced from the bottom end of the stripping apparatus by a distance of from 0 to 30% of the height of the stripping apparatus.

In one embodiment, the oil separation device comprises a settler arranged coaxially or in high-low parallel with the catalytic cracking reactor.

The present application also provides a catalytic cracking method comprising the step of contacting a reaction feedstock with a catalyst in the catalytic cracking system described above.

In one embodiment, the reaction feedstock is selected from light raw oil of C4-C20.

In one embodiment, a reaction directing agent is input to the catalytic cracking reactor through a reaction directing agent inlet of the catalytic cracking reactor, the reaction directing agent being selected from water and petroleum distillate, the petroleum distillate being selected from one or more of a gasoline fraction, a diesel fraction, a wax oil fraction, and an oil slurry.

In one embodiment, the feed weight ratio of the reaction directing agent to the reaction feedstock is from 0.03 to 0.3: 1.

in one embodiment, at least one fuel oil feed port is provided in a lower portion of a stripping unit of the catalytic cracking system and/or a connecting line of the stripping unit and the regenerator;

the method comprises the following steps: and injecting fuel oil through the fuel oil feed port, so that the stripped spent catalyst and the fuel oil enter the regenerator for regeneration.

In one embodiment, the temperature of the regenerated catalyst regenerated by the regenerator is 680-780 ℃.

In the catalytic cracking reactor, the bottom space of the arranged diameter-reducing reaction section, particularly the conical reaction section, is large, so that the density of a catalyst in the reactor can be effectively improved, the ratio of the catalyst to a reaction raw material in the reactor is greatly improved, the primary cracking reaction of the raw material is enhanced, the reaction conversion rate is improved, and the yield of low-carbon olefin can also be improved; moreover, the reducing structure of the reducing reaction section, particularly the conical reaction section, is favorable for accelerating the reaction oil gas to leave the reaction area, shortening the reaction time, reducing the catalyst back mixing, being favorable for reducing the secondary conversion reaction of the low-carbon olefin generated by the primary reaction and improving the selectivity of the low-carbon olefin.

In the catalytic cracking reactor provided by the application, the reaction guiding agent can be sprayed into the downstream of the reaction zone of the catalytic cracking reactor, so that the temperature distribution in the reactor is effectively improved, the process of the cracking reaction is changed, and the technical effect of reducing methane is achieved. In addition, when the guiding agent is petroleum distillate oil, the petroleum hydrocarbon also plays a role of supplementing fuel oil, and is beneficial to improving heat balance.

In the catalytic cracking system that this application provided the stripper lower part can spout into fuel oil, makes fuel oil form additional coke on the catalyst, can evenly distributed in the catalyst bed after getting into the regenerator, and stable, the homogeneous combustion is exothermic under the oxygen-containing gas effect, has realized the cooperative control of fuel oil distribution and scorching on the catalyst, has avoided local hot spot, has effectively protected catalyst performance.

By adopting the catalytic cracking reactor and the catalytic cracking system, chemical raw materials such as ethylene and propylene can be efficiently produced from light petroleum hydrocarbon, and the transformation, development and extension of refinery from oil refining to chemical raw material production are assisted, so that the problem of petrochemical raw material shortage is solved, and the economic benefit of the refinery is improved. When the reactor and the system are used for catalytic cracking reaction, the contact efficiency of raw materials and a catalyst is high, the catalytic reaction selectivity is good, the yield of high value-added products such as ethylene and propylene is high, and the yield of byproducts such as methane is low.

Drawings

The accompanying drawings, which 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 together with the description serve to explain the principles of the application and not to limit the application. In the drawings:

FIG. 1 is a schematic illustration of a catalytic cracking reactor according to one embodiment provided herein.

FIG. 2 is a schematic illustration of a catalytic cracking reactor according to another embodiment provided herein.

FIG. 3 is a schematic illustration of a catalytic cracking system according to one embodiment provided herein.

FIG. 4 is a schematic illustration of a catalytic cracking system according to another embodiment provided herein.

Detailed Description

The present application is described in further detail below with reference to the figures and examples. The features and advantages of the present application will become more apparent from the description.

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

Any specific value disclosed herein (including endpoints of ranges of values) is not to be limited to the precise value of that value, but rather should be construed to also encompass values close to the precise value, for example, all possible values within 5% of the precise value. Also, for the disclosed ranges of values, any combination between the endpoints of the ranges, between the endpoints and specific points within the ranges, and between specific points within the ranges can result in one or more new ranges of values, which should also be considered as specifically disclosed herein.

In the present application, the terms "upstream" and "downstream" are used with reference to the direction of flow of the reactant materials. For example, when the reactant stream flows from bottom to top, "upstream" refers to a position located below, and "downstream" refers to a position located above.

Unless otherwise defined, terms used herein have the same meaning as commonly understood by one of ordinary skill in the art, and if a term is defined herein and its definition is different from the definition commonly understood in the art, the definition herein controls.

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

As shown in fig. 1 and 2, the present application provides a catalytic cracking reactor, which comprises from bottom to top:

an optional pre-lift zone I is provided,

the reaction zone II comprises at least one diameter-reducing reaction section, the diameter-reducing reaction section is a hollow cylinder with a roughly circular cross section and open bottom and top ends, and the inner diameter of the diameter-reducing reaction section is continuously or discontinuously reduced from bottom to top; and

the outlet zone (III) is provided with,

wherein the optional pre-lifting area I is communicated with the bottom end of the reaction area II, the top end of the reaction area II is communicated with the outlet area III, and at least one raw material feeding hole 9 is formed in the optional pre-lifting area and/or the bottom of the reaction area;

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;

one or more reaction guiding agent inlets 10 are arranged at the downstream of the reaction zone II, and the distance between the one or more reaction guiding agent inlets 10 and the outlet end of the reaction zone II is 0-20% of the total height of the reaction zone.

As shown in fig. 1 and 2, the catalytic cracking reactor may include the pre-lift zone I disposed at the lowermost portion of the catalytic cracking reactor for pre-lifting the catalyst, etc. introduced into the reactor. As shown in fig. 1 and 2, the lower portion of the pre-lift zone I is provided with a catalyst inlet 110 for inputting catalyst. The pre-lifting area I can be a hollow cylinder structure, and the ratio of the inner diameter to the height of the pre-lifting area I is 0.02-0.4: 1; the ratio of its height to the total height of the reactor was 0.01: 1 to 0.2: 1, preferably 0.05: 1 to 0.15: 1. in one embodiment, the internal diameter of the pre-lift zone I may be from 0.2 to 5 meters, preferably from 0.4 to 3 meters. In embodiments where a pre-lifting zone I is present, pre-lifting medium may be input to the pre-lifting zone I via the pre-lifting medium line 8. In embodiments where there is a pre-lift zone I, the bottom of the pre-lift zone I may also be provided with at least one catalyst inlet 110 for passing catalyst into the reactor through the pre-lift zone I.

According to the present application, said pre-lifting zone I is not essential, for example when the reaction zone II of the reactor of the present application is used in series with other reactors, such as riser reactors, said reaction zone II can be directly connected to the outlet of the other reactor located upstream, without the need to use said pre-lifting 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 inlet 9 to facilitate the raw material and the like to enter the catalytic cracking reactor. In embodiments where there is no pre-lift zone I, the bottom of the reactor II may be provided with at least one catalyst inlet (not shown) for catalyst to enter the reactor. Of course, the reactor II may not be provided with a catalyst inlet, and the catalyst therein may be derived from catalyst carried in other reactor streams. Both embodiments are within the scope of the present application.

As shown in fig. 1 and 2, the catalytic cracking reactor may include a reaction zone II. The pre-lifting area I is communicated with the bottom end 210 of the reaction area II, the top end 220 of the reaction area II is communicated with the outlet area III, and at least one catalyst inlet 21 and at least one raw material feeding hole 9 are arranged on the pre-lifting area and/or the bottom of the reaction area. The cross-sectional inner diameter of the bottom end 210 of the reaction zone II is greater than or equal to the cross-sectional inner diameter of the pre-lift zone I, and the cross-sectional inner diameter of the top end 220 is equal to or less than the cross-sectional inner diameter of the pre-lift zone I and the cross-sectional inner diameter of the outlet zone III.

In the catalytic cracking reactor provided by the application, the reaction zone II is a fluidized bed, and preferably, the fluidized bed is one or a combination of a conveying fluidized bed, a turbulent fluidized bed and a fast bed.

In one embodiment, the pre-lift 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 can be an isosceles trapezoid, and the camber angle alpha of the side of the isosceles trapezoid can be 5-85 degrees, preferably 15-75 degrees.

As shown in FIG. 1, the raw material feed port 9 may be provided in the upper portion of the pre-lift zone I, in the first transition section I-1, or in the lower portion of the reaction zone II. In particular, in embodiments where there is no pre-lift zone I, the lower part of the reactor II may be provided with a feedstock feed inlet 9 for feeding feedstock.

In one embodiment, the ratio of the internal 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, e.g. 0.2: 1 to 0.75: 1.

in the reactor of the present application, the reaction zone II is provided with one or more reaction directing agent inlets 10 near the outlet. Further preferably, the reaction directing agent inlets 10 are each independently located at a position from 0 to 20% of the exit end of the reaction zone, preferably at a position from 0 to 10% of the exit end of the reaction zone. As shown in FIGS. 1 and 2, the distance L between the one or more reaction guide inlets 10 and the outlet end 220 of the reaction zone II₁₀Independently of one another, the total height h of the reaction zone_II0 to 20%, for example 0% to 10%.

The reaction guiding agent is sprayed into the downstream of the reaction zone of the catalytic cracking reactor, so that the temperature distribution in the reactor can be effectively improved, the course of the cracking reaction is changed, and the technical effect of reducing methane is achieved. In one embodiment, the reaction directing agent may be selected from water and petroleum distillate selected from one or more of a gasoline fraction, a diesel fraction, a wax oil fraction, and an oil slurry. In addition, when the guiding agent is petroleum distillate oil, petroleum hydrocarbon also plays a role of supplementing fuel oil, and is beneficial to improving heat balance.

As shown in fig. 1 and fig. 2, the reaction zone II includes at least one diameter-reducing reaction section, which is a hollow cylinder with a substantially circular cross section and open bottom and top ends, and the inner diameter of the diameter-reducing reaction section decreases continuously or discontinuously from bottom to top.

By "reduced diameter" is meant, according to the present application, that the inner diameter decreases in a discontinuous manner, such as stepwise or in a step-wise or continuous manner. As an example of the "reduced diameter section having an inner diameter which is discontinuously decreased from bottom to top", a column body composed of two or more hollow cylindrical bodies having an inner diameter which is gradually decreased may be cited.

By way of example, the reaction zone II may be of the cylindrical type comprising one or more hollow frustoconical sections, or of the cylindrical type comprising two or more hollow cylindrical sections. Where the reaction zone includes two or more reduced diameter reaction sections, the reduced diameter reaction sections may have the same or different heights, and are not strictly limited herein.

In a preferred embodiment, the reaction zone II comprises a cylinder type consisting of one or more hollow-frustum segments and optionally a connecting segment for connecting adjacent hollow-frustum segments, or a cylinder type consisting of two or more hollow-frustum segments and optionally a connecting segment for connecting adjacent hollow-frustum segments.

In one embodiment, the reaction zone II comprises 1 to 3 reduced diameter reaction sections, such as 1 reduced diameter reaction section 100 (shown in fig. 1), such as 2 reduced diameter reaction sections 100, 100' (shown in fig. 2) in series, such as 3 reduced diameter reaction sections in series.

In one embodiment, as shown in FIG. 1, the reaction zone II comprises 1 reduced diameter reaction section 100 in the form of a hollow truncated cone with a longitudinal section in the form of an isosceles trapezoid; inner diameter D of its tip cross section₂₂₀Height h1 of the reduced diameter reaction section (in FIG. 1, h1 and h)_IIEqual) are each independently from 0.005 to 0.3: 1, inner diameter D of bottom end cross section₂₁₀The ratio of the height h1 of the diameter-reducing reaction sectionEach independently of the others is 0.015 to 0.25: 1, bottom end cross section inner diameter D₂₁₀And the inner diameter D of the cross section of the top end₂₂₀Each independently is greater than 1.2 and less than or equal to 10, more preferably from 1.5 to 5; the ratio of the height of the reduced diameter reaction section h1 to the total reactor height h is independently 0.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1. in one embodiment, the inner diameter D of the cross-section of the bottom end₂₁₀The ratio to the total reactor height h is 0.01: 1 to 0.5: 1, preferably 0.05: 1 to 0.2; the ratio of the height h1 of the one or more reduced diameter reaction sections to the total reactor height h is each independently 0.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1 and the total height h of the reaction zone II_IIThe ratio of h to the total reactor height is 0.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1. in one embodiment, the reduced diameter reaction section 100 has an inner diameter D at its tip cross-section₂₁₀Is 0.2-5 m, preferably 0.4-3 m. In one embodiment, the total height h of the reaction zone II_IIMay be about 2-50 meters, preferably about 5-40 meters, more preferably about 8-20 meters.

In one embodiment, as shown in FIG. 2, the reaction zone II comprises 2 sections of reduced diameter reaction sections 100,100 'connected in series, each reduced diameter reaction section 100, 100' having a hollow truncated cone shape with a longitudinal section in the shape of an isosceles trapezoid; inner diameter D of its tip cross section₂₂₀、D_220’The ratio of the height h1 to the height h 1' of the diameter-reducing reaction section is 0.005-0.3: 1, inner diameter D of bottom end cross section₂₁₀、D_210’The ratio of the height h1 to the height h 1' of the diameter-reducing reaction section is 0.015-0.25: 1, bottom end cross section inner diameter D₂₁₀、D_210’And the inner diameter D of the cross section of the top end₂₂₀、D_220’Each independently is greater than 1.2 and less than or equal to 10, more preferably from 1.5 to 5; the ratio of the height of the reduced diameter reaction sections h1, h 1' to the total reactor height h is independently 0.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1. in one embodiment, the bottom end cross-section has an inner diameter D₂₁₀、D_220’The ratio to the total reactor height h is 0.01: 1 to 0.5: 1, preferably 0.05: 1 to 0.2; the height h1, h 1' of the one or more reduced diameter reaction sections and the total height of the reactorThe ratio of the degrees h is each independently 0.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1, and the total height h of the reaction zone II_IIThe ratio to the total reactor height h is 0.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1. in one embodiment, the reduced diameter reaction section 100, 100' has an inner diameter D of the top cross-section₂₁₀、D_210’Each independently of the other, from 0.2 to 5 m, preferably from 0.4 to 3 m. In one embodiment, the total height h of the reaction zone II_IIMay be about 2-50 meters, preferably about 5-40 meters, more preferably about 8-20 meters.

In one embodiment, the reduced diameter reaction sections 100, 100' are connected by a second transition section II-1. The longitudinal section of the second transition section II-1 can be an isosceles trapezoid, and the camber angle alpha of the side edge of the isosceles trapezoid can be 5-85 degrees, preferably 15-75 degrees.

In other embodiments, the reaction zone comprises one or more reduced diameter reaction sections each independently comprising two or more hollow cylinders of decreasing inner diameter, in which case the reaction zone is of the cylindrical type comprising two or more hollow cylinder sections. The two or more hollow cylinder sections each independently have a cross-sectional internal diameter of from 0.2 to 5 meters, preferably from 0.4 to 3 meters, the ratio of this internal diameter to the total reactor height being from 0.01: 1 to 0.5: 1, preferably 0.05: 1 to 0.2, the ratio of the height of the two or more hollow cylinder sections to the total reactor height each independently being 00.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1 and the ratio of the height of the reaction zone to the total reactor height is 0.15: 1 to 0.8: 1, preferably 0.2: 1 to 0.75: 1.

in the catalytic cracking reactor provided herein, the reactor may be provided with one or more, e.g., one, two or more,

feedstock feed inlets

9,16, and the one or more

feedstock feed inlets

9,16 may be each independently provided at the outlet end of the pre-lift zone I, or at the bottom of the reaction zone II. Further preferably, the positions of the plurality of raw material inlets are each independently located at the same height or different heights of the reaction zone II. As shown in FIG. 2, one feed inlet 9 can be located at the outlet end of the pre-lift zone I and another feed inlet 16 can be located at the outlet end of the first reduced diameter reaction section 100 of the reaction zone II. Thus, different materials, such as C4-C12 hydrocarbon material, may be fed at material feed inlet 9 and C12-C20 hydrocarbon material may be fed at material feed inlet 16.

As shown in fig. 1 and 2, 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_IIIThe ratio of (A) to (B) is 0.01-0.3: 1, height h of said exit area_IIIThe ratio to the total reactor height h 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 from 0.2 to 5 meters, preferably from 0.4 to 3 meters.

As mentioned above, the cross-sectional inner diameter at the top end of the reaction zone II is equal to or smaller than the cross-sectional inner diameter of the outlet zone III. In one embodiment, the cross-sectional internal diameter at the top end of reaction zone II is equal to the cross-sectional internal diameter of said outlet zone III.

In one embodiment, the cross-sectional inner diameter at the top end of reaction zone II is smaller than the cross-sectional inner diameter of said outlet zone III. In this case, the reaction zone II and the outlet zone III may be connected via a third transition piece (not shown). The longitudinal section of the third transition section may be an isosceles trapezoid, and the camber angle α of the side of the isosceles trapezoid may be 5 to 85 °, preferably 15 to 75 °.

The outlet end of the outlet zone III may be open or may be connected directly to the inlet of the cyclone.

The present application further provides a catalytic cracking system, the catalytic cracking system includes catalytic cracking reaction unit, finish separator, steam stripping device, optional reaction product separator, and regenerator, wherein, the catalytic cracking reaction unit includes one or more above-mentioned catalytic cracking reactors of this application.

Fig. 3 and 4 show a catalytic cracking system comprising the above-described catalytic cracking reactor of the present application. In which the catalytic cracking reactor of fig. 3 is shown in fig. 1 and the catalytic cracking reactor of fig. 4 is shown in fig. 2.

As shown in fig. 3 and 4, the catalytic cracking system comprises the above-mentioned catalytic cracking reactor 1 of the present application, an oil separation device 5, a settler 3, a stripper 4, and a regenerator 2,

the catalytic cracking reactor 1 is provided with a catalyst inlet 13 at the bottom, raw

material feed inlets

9 and 16 at the lower part and an oil agent outlet 150 at the top;

the oil agent separation device 5 is used for separating reaction products and catalysts in the oil agent from the catalytic cracking reactor 1;

the settler 3 is used for leading the catalyst separated by the oil agent separator 5 to be settled and then to enter the stripping device 4;

the stripping device 4 is used for stripping the catalyst in the reaction oil gas to recover the reaction oil gas;

the regenerator 2 is connected with the stripping device 4 through a spent inclined tube 12 and is used for enabling spent catalyst from the stripping device 4 to enter the regenerator 2 for regeneration; the regenerator 2 is also connected with the catalytic cracking reactor 1 through a regeneration inclined pipe 13 and is used for circulating the regenerated catalyst regenerated by the regenerator 2 back to the catalytic cracking reactor 1 for reaction.

In the catalytic cracking system of the present application, the catalytic cracking reactor may be one or more, may be a combination of one catalytic cracking reactor of the present application and other existing catalytic cracking reactors, and may also be a combination of a plurality of catalytic cracking reactors of the present application. The reactors can be connected in parallel and connected with an oil separation device.

The reaction oil gas (i.e. reaction product) separated by the oil agent separation device 5 is collected in the gas collection chamber 6 and then is conveyed to a subsequent reaction product separation device (not shown) through a line 7 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 oil outlet and a pyrolysis heavy oil outlet, and is used for separating the reaction product into dry gas, liquefied gas, pyrolysis gasoline, pyrolysis diesel oil, pyrolysis heavy oil and the like according to the distillation range of the reaction product.

In the regenerator 2, the spent catalyst is combusted under the action of oxygen-containing regeneration gas introduced through a pipeline 14 to obtain a regenerated catalyst, and the regenerated catalyst is input into the reactor 1 through a regeneration inclined pipe 13; and the flue gas exits through line 15 into an energy recovery system.

In the catalytic cracking system of the present application, at least one fuel oil feed port may be provided in the lower portion of the stripping unit 4 and/or in the connecting line 12 between the stripping unit and the regenerator for supplying additional fuel oil to the spent catalyst. Therefore, the fuel oil can form additional coke on the spent catalyst before entering the regenerator, the fuel oil is uniformly distributed in the catalyst bed after entering the regenerator, and can be stably and uniformly combusted to release heat under the action of the oxygen-containing gas, so that the cooperative control of the fuel oil distribution and the coke burning on the catalyst is realized, local hot spots are avoided, and the service performance of the catalyst is effectively protected.

In one embodiment, at least one fuel oil inlet 11 is provided at the lower part of the stripping apparatus, wherein the fuel oil inlet 11 is at a distance L from the bottom end of the stripping apparatus₁₁Each independently of the stripping unit height h₄0-30%, preferably 5% -25%.

In the catalytic cracking system provided by the present application, the stripping device, the oil separation device, the regenerator, other devices, the reaction product separation device, and the like can all adopt devices known to those skilled in the art, and the connection manner between the devices can also be performed according to a manner known in the art. For example, the oil separation device can comprise a cyclone separator and an outlet quick separator. In certain embodiments, the oil separation device comprises a settler arranged coaxially or in high-low parallel with the catalytic cracking reactor.

In another aspect, the present application provides a catalytic cracking method comprising the step of contacting a reaction feedstock with a catalyst in a catalytic cracking system as described herein above.

The catalytic cracking reactor and the catalytic cracking system provided by the application are suitable for catalytic cracking reaction of various raw materials, such as light hydrocarbon or light distillate oil, oxygenated hydrocarbons, shale oil, hydrorefined wax oil, hydroupgraded wax oil, hydrocracking tail oil or a mixed raw material of one or more of the raw materials for producing low-carbon olefin by catalytic cracking, and particularly for producing low-carbon olefin by catalytic cracking of light hydrocarbon or light distillate oil.

For example, the light hydrocarbon or light distillate oil can be gas hydrocarbon, petroleum hydrocarbon with the distillation range of 25-350 ℃, oxygen-containing compound, biomass or distillate oil of waste plastic generated oil; the gaseous hydrocarbon may be selected from one or more of a saturated liquefied gas, an unsaturated liquefied gas, a carbon four-cut mixture; the petroleum hydrocarbon may be selected from one or more of primary processed straight run naphtha, straight run kerosene, straight run diesel; one or more of secondary processed topping oil, raffinate oil, hydrocracking light naphtha, pentane oil, coker gasoline, Fischer-Tropsch synthetic oil, catalytic cracking light gasoline, hydrogenated gasoline and hydrogenated diesel oil. In one embodiment, the reaction feedstock is selected from light raw oil of C4-C20.

In one embodiment, the reaction conditions within the reaction zone include: the reaction temperature is 510-750 ℃, the reaction time is 0.5-10 seconds, the weight ratio of the catalyst to the oil is 10: 1 to 50: 1, the weight ratio of water to oil is 0.05: 1 to 2.0: 1.

in one embodiment, the reaction conditions within the reaction zone include: the reaction temperature is 550-700 ℃, the reaction time is 1-5 seconds, and the weight ratio of the catalyst to the oil is 20: 1 to 40: 1, the weight ratio of water to oil is 0.2: 1 to 0.8: 1.

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

In one embodiment, the zeolite comprises a medium pore zeolite selected from the group consisting of ZSM series zeolites, ZRP zeolites, and any combination thereof, and optionally a large pore zeolite; the large pore zeolite is selected from the group consisting of rare earth Y-type zeolite, rare earth hydrogen Y-type zeolite, ultrastable Y-type zeolite, and high silicon Y-type zeolite, and any combination thereof.

In one embodiment, the medium pore zeolite comprises from 10 to 100 wt%, preferably from 50 to 90 wt%, of the total weight of the zeolite on a dry basis.

In this application, the medium and large pore zeolites are as conventionally defined in the art, i.e., the medium pore size of the medium pore zeolite is from about 0.5 to 0.6nm and the large pore zeolite is from about 0.7 to 1.0 nm.

By way of example, the large-pore zeolite may be selected from one or more of rare earth Y (rey) type zeolites, rare earth hydrogen Y (rehy) type zeolites, ultrastable Y-type zeolites obtained by different processes, and high-silica Y-type zeolites. The medium pore zeolite may be selected from zeolites having the MFI structure, such as ZSM series zeolites and/or ZRP zeolites. Optionally, the mesoporous zeolite may be modified with a nonmetallic element such as phosphorus and/or a transition metal element such as iron, cobalt, nickel. A more detailed description of ZRP zeolites can be found in U.S. Pat. No. US5,232,675A. The ZSM-series zeolite is preferably one or a mixture of more selected from ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48 and other zeolites of similar structure. A more detailed description of ZSM-5 is described in U.S. Pat. No. US3,702,886A.

According to the application, the inorganic oxide is preferably silicon dioxide (SiO) as a binder₂) And/or aluminum oxide (Al)₂O₃). The clay acts as a matrix (i.e., carrier), preferably kaolin and/or halloysite.

The weight ratio of the injected fuel oil to the feeding weight of the reaction raw materials is 0.05-0.2: 1. in one embodiment, the temperature of the regenerated catalyst regenerated by the regenerator is 680-780 ℃.

By adopting the catalytic cracking reactor, the system and the method, the chemical raw materials such as ethylene, propylene and the like can be efficiently produced from light petroleum hydrocarbon, and the transformation, development and extension of refinery from oil refining to chemical raw material production are assisted, so that the problem of petrochemical raw material shortage is solved, and the economic benefit of the refinery is improved.

The present application will be further described with reference to preferred embodiments shown in the drawings, but the application is not limited thereto.

Fig. 1 shows a preferred embodiment of the catalytic cracking reactor of the present application, wherein the catalytic cracking reactor 1 comprises a pre-lift zone I, a reaction zone II, and an outlet zone III in sequence from bottom to top. The reaction zone II comprises a reducing reaction section 100 in the form of a hollow truncated cone with an isosceles trapezoid longitudinal section. The lower part of the pre-lifting area I is provided with a catalyst inlet 110, and the upper part of the pre-lifting area I and/or the bottom of the reaction area II is provided with a raw material inlet 9. The inner diameter of the cross section of the bottom end of the reaction zone II is larger than that of the pre-lifting zone I, and the inner diameter of the cross section of the top end of the reaction zone II is equal to that of the pre-lifting zone I and that of the outlet zone III. The downstream side wall of the reaction zone II is provided with one or more, e.g. one, two or more reaction director inlets 10.

Fig. 3 shows a catalytic cracking system comprising the catalytic cracking reactor 1 of fig. 1, wherein the lower side wall of the stripper 4 is provided with one or more, e.g. one, two or more, supplementary fuel oil inlets 11.

The pre-lift medium, which may be dry gas, steam or a mixture thereof, enters the catalytic cracking reactor 1 from the bottom of the pre-lift zone I via line 8. The hot regenerated catalyst from the regeneration chute 13 enters the lower part of the pre-lift zone I and moves upwards under the lifting action of the pre-lift medium. Reaction raw materials such as preheated light raw oil and atomized steam are injected into the upstream of the pre-lifting zone I and/or the bottom of the reaction zone II through a feed line 9, are mixed and contacted with the existing catalyst in the catalytic cracking reactor, and carry out catalytic cracking reaction in the process of passing through the reaction zone II from bottom to top. The reaction product flows upwards and contacts with the reaction guiding agent injected through the reaction guiding agent inlet 10, so that the reaction is stopped in time, the obtained catalyst with coke and the reaction oil gas enter an oil agent separation device 5 such as a cyclone separator through an outlet region III for gas-solid separation, and the separated reaction oil gas is led out of the device through a gas collection chamber 6 and a large oil gas pipe 7 and enters a subsequent separation system; the separated catalyst with coke enters a stripper, the stripped spent catalyst is contacted with fuel oil injected through a supplementary fuel oil inlet 11, the coke is further deposited, the catalyst enters a regenerator 2 through a spent inclined tube 12 and is mixed with air 14 at the bottom of the regenerator to be burned and regenerated, the regenerated catalyst returns to the reactor 1 through a regenerated inclined tube 13 for recycling, and the regenerated flue gas enters an energy recovery system through a pipeline 15.

Fig. 2 shows another preferred embodiment of the catalytic cracking reactor of the present application, wherein the reactor comprises, from bottom to top, a pre-lift zone I, a reaction zone II, and an outlet zone III. The reaction zone II comprises 2 reducing reaction sections 100, 100' which are cylinder type comprising two hollow truncated cone sections, and the longitudinal section of each hollow truncated cone section is isosceles trapezoid. The lower part of the pre-lifting area I is provided with a catalyst inlet, the upstream of the pre-lifting area I and/or the bottom of the first reaction section 100 is provided with a raw material feeding hole, and the bottom of the second reaction section 100' is provided with a raw material or recycle material feeding hole. The cross-sectional inner diameter of the bottom end of each hollow frustum section is larger than the inner diameter of the pre-lifting area I, and the cross-sectional inner diameter of the top end is equal to the inner diameter of the pre-lifting area I and the inner diameter of the outlet area II. The downstream side wall of the second reaction section is provided with one or more, for example one, two or more, reaction director inlets 10.

Fig. 4 shows a catalytic cracking system comprising the catalytic cracking reactor 1 of fig. 2, wherein the lower side wall of the stripper is provided with one or more, e.g. one, two or more, supplementary fuel oil inlets 11.

The pre-lift medium, which may be dry gas, steam or a mixture thereof, enters the catalytic cracking reactor from the bottom of the pre-lift zone I via line 8. The hot regenerated catalyst, with or without cooling, from the regeneration ramp 13 enters the lower part of the pre-lift zone I and moves upwards under the lifting action of the pre-lift medium. Reaction raw materials such as preheated light raw oil and atomized steam are injected into the upstream of a pre-lifting area I and/or the bottom of a first reaction section 100 through a feeding pipeline 9, are mixed, contacted and reacted with the existing catalyst in a catalytic cracking reactor, reactant flow is mixed with recycle C4 introduced from the bottom of a second reaction section 100' through a pipeline 16 for further reaction, reaction products flow upwards, are contacted with a reaction guiding agent injected through a pipeline 10 to quench the cracking reaction in time, the catalyst with coke and reaction oil gas enter an oil separating device 5 such as a cyclone separator through an outlet area III to carry out gas-solid separation, and the separated reaction oil gas enters a subsequent separating system through a gas collection chamber 6 and a large oil gas pipe 7 leading-out device; the separated catalyst with coke enters a stripper, the stripped spent catalyst is contacted with fuel oil injected through a supplementary fuel oil inlet 11, the coke is further deposited, the catalyst enters a regenerator 2 through a spent inclined tube 12 and is mixed with air 14 at the bottom of the regenerator to be burned and regenerated, the regenerated catalyst returns to the reactor 1 through a regenerated inclined tube 13 for recycling, and the regenerated flue gas enters an energy recovery system through a pipeline 15.

Examples

The following examples further illustrate the present application but are not intended to limit the same.

The raw material oils used in the following examples and comparative examples were straight run naphthas having the properties shown in Table 1, and the catalysts used were commercial catalytic cracking catalysts available from catalyst division of petrochemical Co., Ltd., China under the trade designation NCC.

Example 1

Using the feed oil and NCC catalyst shown in Table 1, a test was conducted on a medium-sized apparatus shown in FIG. 1, wherein the reactor used had the following structure:

the total height of the reactor was 10 m, with a pre-lift zone of 2 m and an internal diameter of 0.2 m; the height of the reaction zone is 5 meters, the inner diameter of the cross section at the top end is 0.2 meter, and the inner diameter of the cross section at the bottom end is 0.3 meter; the height of the outlet zone is 3 meters, and the inner diameter is 0.2 meter. The reaction directing agent inlet was positioned 0.5 meters from the outlet end.

In the stripper, the supplemental fuel oil inlet is located at a distance of 10% of the height of the stripping unit from the bottom end of the stripping unit.

The hot regenerated catalyst from the regeneration chute 13 enters the lower part of the pre-lift zone I and moves upwards under the lifting action of the pre-lift medium. Preheated raw oil and atomized steam are injected into the upper part of the pre-lifting area I through a feeding pipeline 9, are mixed and contacted with the existing catalyst in the catalytic cracking reactor, and carry out catalytic cracking reaction in the process of passing through the reaction area II from bottom to top. The reaction product flows upwards and contacts with the reaction guiding agent injected through the reaction guiding agent inlet 10, so that the reaction is stopped in time, the obtained catalyst with coke and the reaction oil gas enter an oil agent separation device 5 such as a cyclone separator through an outlet region III for gas-solid separation, and the separated reaction oil gas is led out of the device through a gas collection chamber 6 and a large oil gas pipe 7 and enters a subsequent separation system; the separated catalyst with coke enters a stripper, the stripped spent catalyst is contacted with fuel oil injected through a supplementary fuel oil inlet 11, coke is further deposited, the coke enters a regenerator 2 through a spent inclined tube 12 and is mixed with air 14 at the bottom of the regenerator to be burnt and regenerated, the regenerated catalyst returns to the reactor 1 through a regenerated inclined tube 13 for recycling, and the regenerated flue gas enters an energy recovery system through a pipeline 15.

During operation, the ratio of the injection amount of the reaction directing agent to the feeding amount of the raw materials is 0.05: 1 (weight) and the amount of fuel oil injected was 6% of the feed amount of the raw material.

The operating conditions and the product distribution are listed in table 2. As can be seen from table 2, the ethylene yield of this example reached 25.53 wt%, the propylene yield reached 24.21 wt%, and the methane and coke yields were 10.07 wt% and 3.70 wt%, respectively.

Example 2

Using the feed oil and NCC catalyst shown in Table 1, the test was conducted on a medium-sized apparatus of the type shown in FIG. 2, in which the reaction zone comprised two hollow frustum sections in series, wherein,

the reactor used has the following construction:

the total reactor height was 10 meters. Wherein the pre-lifting area is 2 meters, and the inner diameter is 0.2 meter; the height of the reaction zone was 5 meters, with a height h1 of the first hollow frustocone section of 2.5 meters, an internal diameter of the top cross-section of 0.2 meters and an internal diameter of the bottom cross-section of 0.3 meters; the height h1 of the second hollow frustocone section is 2.45 meters, the internal diameter of the top cross section is 0.2 meters and the internal diameter of the bottom cross section is 0.3 meters; the outlet zone was 3 metres high with an internal diameter of 0.2 metres. The reaction director inlet was positioned at a distance of 0.2 meters from the outlet end of the second hollow conical frustum.

The hot regenerated catalyst, with or without cooling, from the regeneration ramps 13 enters the lower part of the pre-lift zone I and moves upwards under the lifting action of the pre-lift medium. Preheated raw oil enters the upper part of a pre-lifting area from a feed inlet 9 to be contacted with a catalytic cracking catalyst and sequentially enters two reaction sections from bottom to top to carry out catalytic cracking reaction, the preheated raw oil is introduced into a back refining C4 at the bottom of a second reaction section 100' through a pipeline 16 to further react, a reaction product flows upwards and contacts with a reaction guiding agent injected through a pipeline 10 to quench the cracking reaction in time, the catalyst with coke and reaction oil gas enter an oil agent separation device 5 such as a cyclone separator through an outlet area III to carry out gas-solid separation, and the separated reaction oil gas enters a subsequent separation system through a gas collection chamber 6 and a large oil gas pipe 7 leading-out device; the separated catalyst with coke enters a stripper, the stripped spent catalyst is contacted with fuel oil injected through a supplementary fuel oil inlet 11, the coke is further deposited, the catalyst enters a regenerator 2 through a spent inclined tube 12 and is mixed with air 14 at the bottom of the regenerator to be burned and regenerated, the regenerated catalyst returns to the reactor 1 through a regenerated inclined tube 13 for recycling, and the regenerated flue gas enters an energy recovery system through a pipeline 15.

The operating conditions and the product distribution are listed in table 2. As can be seen from table 2, the ethylene yield of this example reached 26.53 wt%, the propylene yield reached 26.13 wt%, and the methane and coke yields were 10.77 wt% and 3.86 wt%, respectively.

Comparative example 1

The experiments were carried out on a medium-sized apparatus using the base oil and NCC catalyst shown in Table 1, and the reactor was a conventional riser reactor. The preheated raw oil enters the lower part of a riser reaction zone to contact with a catalytic cracking catalyst for catalytic cracking reaction, and the material flow after the reaction enters a subsequent oil agent separation device and a product separation device; the operating conditions and the product distribution are listed in table 2.

As can be seen from the results of table 2, the comparative example had an ethylene yield of only 18.19 wt%, a propylene yield of only 20.14 wt%, and methane and coke yields of 12.95 wt% and 3.92 wt%, respectively.

From the results of the above examples and comparative examples, it can be seen that when the catalytic cracking reactor and system of the present application is used for naphtha catalytic cracking reaction, the yields of ethylene and propylene are significantly increased, and the yields of methane and coke are reduced.

The preferred embodiments of the present application have been described in detail above, but the present application is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present application within the technical idea of the present application, and these simple modifications all belong to the protection scope of the present application.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various possible combinations are not described in the present application.

In addition, any combination of the various embodiments of the present application is also possible, and the same should be considered as the content of the invention of the present application as long as it does not depart from the idea of the present application.

TABLE 1 Properties of the straight run naphtha used

Density (20 ℃ C.)/(g/cm)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/. degree.C
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
		Composition of hydrocarbons/weight%
Alkane hydrocarbons	58.30
		Olefins	0
Cycloalkanes	30.18
		Aromatic hydrocarbons	11.52

TABLE 2 comparison of reaction results of examples 1-2 and comparative example 1

	Example 1	Example 2	Comparative example 1
				Reaction zone conditions
Outlet temperature of reaction zone,. deg.C	675	675	675
				Reaction time in seconds	2.0	2.1	2.5
Water to oil weight ratio	0.3	0.3	0.3
				Weight ratio of solvent to oil	30	30	30
Percent of recycled carbon four in weight of raw material		10
				Product distribution, weight%
H2～C2	40.31	42.32	39.44
				Wherein methane	10.07	10.77	12.95
Wherein ethylene	25.53	26.53	18.19
				C3～C4	38.15	34.79	36.49
Wherein propylene is	24.21	26.13	20.14
				Gasoline (gasoline)	15.55	16.73	17.23.
Fuel oil	2.29	2.30	2.92
				Coke	3.70	3.86	3.92
Total up to	100	100	100

Claims

1. The catalytic cracking reactor is characterized by comprising the following components in sequence from bottom to top:

optionally a pre-lift zone, in which the pre-lift zone is located,

the outlet area is provided with a plurality of outlet areas,

2. The catalytic cracking reactor of claim 1, wherein the ratio of the bottom cross-sectional inner diameter of the reaction zone to the total reactor height 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 was 0.15: 1 to 0.8: 1.

3. the catalytic cracking reactor of claim 1, wherein the reaction zone comprises 1-3 reduced diameter reaction sections.

4. A catalytic cracking reactor as claimed in claim 3, characterised in that the reduced diameter reaction section is of hollow frusto-conical form with longitudinal sections in the form of isosceles trapezoids; the ratio of the inner diameter of the top end cross section to the height of the reducing reaction section is respectively and independently 0.005-0.3: 1, the ratio of the inner diameter of the cross section of the bottom end to the height of the reducing reaction section is respectively and independently 0.015-0.25: 1, the ratio of the bottom end cross section inner diameter to the top end cross section inner diameter is respectively and independently more than 1.2 and less than or equal to 10; the ratio of the height of the diameter-reducing reaction section to the total height of the reactor is respectively and independently 0.15: 1 to 0.8: 1.

5. the catalytic cracking reactor of claim 4, wherein the reduced diameter reaction section has a top end cross-section each independently having an inner diameter of 0.2 to 5 meters.

6. The catalytic cracking reactor of claim 1, wherein the pre-lift zone has an internal diameter to height ratio of 0.02 to 0.4: 1; the ratio of its height to the total height of the reactor was 0.01: 1 to 0.2: 1.

7. the catalytic cracking reactor of claim 6, wherein the pre-lift zone has an internal diameter of 0.2 to 5 meters.

8. The catalytic cracking reactor of claim 6, wherein the pre-lifting zone and the reaction zone are connected by a first connecting section, the longitudinal section of the first connecting section is an isosceles trapezoid, and the outer inclination angle α of the side of the isosceles trapezoid is 5-85 °.

9. The catalytic cracking reactor of claim 1, wherein the outlet zone has a cross-sectional inner diameter to height ratio of 0.01 to 0.3: 1, the ratio of the height of the outlet zone to the total reactor height being 0.05: 1 to 0.5: 1.

10. the catalytic cracking reactor of claim 9, wherein the outlet zone has a cross-sectional inner diameter of 0.2 to 5 meters.

11. A catalytic cracking system comprising a catalytic cracking reaction unit, an oil separation unit, a stripping unit, an optional reaction product separation unit, and a regenerator, characterized in that the catalytic cracking reaction unit comprises one or more catalytic cracking reactors according to any one of claims 1 to 10.

12. The catalytic cracking system of claim 11, wherein at least one fuel oil feed port is provided in a lower portion of the stripping device and/or a connecting line of the stripping device and the regenerator.

13. The catalytic cracking system of claim 12, wherein at least one fuel oil feed inlet is provided at a lower portion of the stripping apparatus,

14. The catalytic cracking system of claim 12 or 13, wherein the oil separation device comprises a settler arranged coaxially or in high-low parallel with the catalytic cracking reactor.