A method and system for catalytic cracking reaction coupled with coke formation

Abstract

The application relates to a catalytic cracking method and system coupling reaction and coking, which comprises the following steps: feeding light oil and regenerated catalyst into a cracking reactor to carry out a catalytic cracking reaction, so as to obtain reaction products and spent catalyst; feeding coking raw material and the spent catalyst into a coking reactor to carry out a coking reaction, so as to obtain reaction products and carbon-containing catalyst; introducing the reaction products into a separation system to separate the products; and feeding the spent catalyst and the carbon-containing catalyst into a regenerator to carry out a coking regeneration and recycling. The catalytic cracking method can not only reduce the methane yield and improve the ethylene and propylene selectivity, but also provide coke for the regeneration process, solve the reaction heat balance problem, and improve the catalytic reaction selectivity without damaging the physical and chemical properties of the catalyst.

Description

Technical Field

[0001] This application relates to the field of fluidized catalytic cracking technology, and more specifically, to a reaction method and system for reaction coupled with coke production catalytic cracking. Background Technology

[0002] Currently, there is an overcapacity in oil refining, coupled with a slowdown in end-user consumption of refined oil products. This structural oversupply of refined oil products has become a pressing issue for refining companies. In the chemical feedstock market, ethylene and propylene, as basic chemical raw materials, continue to face strong demand. Ethylene and propylene consumption is increasing year by year. Taking my country as an example, it is estimated that by the end of 2023, my country's ethylene and propylene production capacity will reach approximately 44 million tons / year and 52 million tons / year, respectively, with average annual compound growth rates of 11.5% and 8.7%. Consequently, the domestic refining landscape and resource flows will undergo structural restructuring, with a slowdown in the growth rate of end-user consumption of refined oil products and a significant increase in the consumption of light chemical oils. Therefore, the transformation from refining to chemical processing has become an inevitable direction for refinery development. Catalytic cracking, as the link between refining and chemical processing, is a key technology in this transformation process.

[0003] Catalytic cracking processes typically use heavy petroleum hydrocarbons as feedstock, especially paraffin-based vacuum fractions or atmospheric residue, which offer high yields of low-carbon olefins such as propylene. With the increasing weight and quality of crude oil globally, high-quality heavy petroleum hydrocarbon resources are becoming increasingly scarce, necessitating the expansion of the feedstock adaptability of catalytic cracking technology. As refineries adjust and transform their product structures, they are also generating significant amounts of light petroleum hydrocarbons as a byproduct while improving oil quality. For a typical 10 million-ton-scale fuel oil refinery, the annual output of light petroleum hydrocarbons can reach one million tons, accounting for approximately 10% of crude oil processing. For integrated refining and chemical plants or chemical-type refineries, the increased depth of crude oil resource conversion will lead to a substantial increase in both the output and proportion of light petroleum hydrocarbons. How to efficiently utilize these light hydrocarbon resources has become a key focus of research and attention in the refining and chemical industry.

[0004] In catalytic cracking technology targeting low-carbon olefins as the main product, the cracking reaction has high conversion rates, high temperatures, and large heats of reaction. The heat required for the reaction is significantly higher than that of conventional fluidized bed catalytic regenerators or other catalytic conversion methods. The coke generated by the cracking process itself often cannot meet the heat balance requirements of the reaction-regeneration system. If the feedstock is made lighter, the problem of insufficient heat source will be exacerbated. When insufficient coke is generated during the reaction, oil slurry reprocessing or external fuel oil supplementation to the regenerator is typically used to provide the necessary heat for the reaction. However, because the oil slurry contains a large amount of polycyclic aromatic hydrocarbons, it is easily adsorbed at the active sites of the catalyst, affecting the accessibility of the active sites of the feedstock molecules and thus impacting the selectivity of the catalytic reaction. Furthermore, since catalytic cracking uses molecular sieves as the active component of the catalyst, the localized high temperatures generated by the combustion of fuel oil in the regenerator cause aluminum in the molecular sieve framework to gradually detach, leading to irreversible damage to the catalyst. This does not fundamentally solve the problem of the impact of high-temperature hotspots generated by the localized combustion of externally supplemented fuel oil on the catalyst framework structure and reaction performance.

[0005] To address this issue, existing technologies all focus on the regenerator system. For example, they may introduce an oxygen-deficient zone within the regenerator, mixing fuel oil with the catalyst before coking and regenerating it; or install heaters within the regenerator and use fuel nozzles configured to inject a mixture of fuel and oxygen-containing gas to supplement combustion heat; or inject methane, relying on the heat released from methane combustion to supplement the reaction heat. While these methods mitigate the adverse effects on the catalyst, they do not fundamentally address the impact of high-temperature hotspots generated by the localized combustion of externally supplied fuel oil on the catalyst's framework structure and reaction performance, thus severely affecting reaction selectivity. Therefore, while developing light oil catalytic cracking technology to improve the selectivity of low-carbon olefins, addressing insufficient thermal balance is also a crucial technical problem that must be solved. Summary of the Invention

[0006] The purpose of this application is to provide a catalytic cracking method and system that couples reaction with coke production, thereby increasing the yield of ethylene and propylene, reducing methane selectivity, providing a coke source for the regeneration process, reducing the temperature of the reaction oil and gas, and facilitating product separation and recovery.

[0007] This application provides a catalytic cracking reaction-regeneration system, including a catalytic cracking reaction system, a coking reaction system, and a regeneration system.

[0008] The catalytic cracking reaction system includes a cracking reactor, a first oil-to-oil separation device, and a first settling tank.

[0009] The pyrolysis reactor is provided with a pre-lift gas inlet at the bottom, a catalyst inlet, one or more pyrolysis feedstock inlets, and an oil agent outlet at the top; the oil agent outlet of the pyrolysis reactor is in fluid communication with the first oil agent separation device, so that the first reaction oil and gas and the first catalyst to be generated from the catalytic pyrolysis reactor are separated in the first oil agent separation device;

[0010] The first settling device is configured to collect the first catalyst to be generated separated in the first oil-agent separation device, and is provided with a first catalyst to be generated outlet and a second catalyst to be generated outlet; the coking reaction system includes a coking reactor, a second oil-agent separation device and a second settling device;

[0011] The coke reactor is provided with a pre-lift gas inlet at the bottom, a catalyst inlet, a coke raw material inlet at the bottom, and an oil outlet at the top; wherein, the catalyst inlet of the coke reactor is fluidly connected to the outlet of the first catalyst to be generated in the first settling tank, so that at least a portion of the first catalyst to be generated enters the coke reactor; the oil outlet of the coke reactor is fluidly connected to the second oil separation device, so that the second reaction oil gas and the second catalyst to be generated from the coke reactor are separated in the second oil collection device;

[0012] The second settling device is configured to collect the second catalyst to be generated separated in the second oil-separation device, and is provided with a third catalyst to be generated outlet;

[0013] The regeneration system is provided with a catalyst inlet and a catalyst outlet; wherein, the catalyst inlet is fluidly connected to the second catalyst outlet of the first settling tank and the third catalyst outlet of the second settling tank, so that the remaining first catalyst and second catalyst enter the regeneration system for regeneration; the catalyst outlet is also fluidly connected to the catalyst inlet of the cracking reactor, so that the catalyst enters the cracking reactor.

[0014] In one embodiment, the catalytic cracking reactor comprises, from bottom to top:

[0015] Optional pre-promotion area;

[0016] The reaction zone includes at least one diameter-reducing reaction section, which is a hollow cylinder with a generally circular cross-section and open at the bottom and top, its inner diameter decreasing continuously or discontinuously from bottom to top; and

[0017] Export zone;

[0018] The optional pre-lifting zone is connected to the bottom of the reaction zone, the top of the reaction zone is connected to the outlet zone, and at least one raw material inlet is provided on the optional pre-lifting zone and / or at the bottom of the reaction zone.

[0019] The inner diameter of the cross-section at the bottom of the reaction zone is greater than or equal to the inner diameter of the cross-section of the optional pre-lift zone, and the inner diameter of the cross-section at the top is equal to or less than the inner diameter of the cross-section of the optional pre-lift zone and the inner diameter of the cross-section of the outlet zone; the regenerated catalyst inlet is provided at the bottom of the reaction zone and / or the optional pre-lift zone.

[0020] In one embodiment, the ratio of the inner diameter of the bottom cross-section of the reaction zone of the catalytic cracking reactor 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.

[0021] In one embodiment, the reaction zone of the catalytic cracking reactor includes 1-3 narrowing reaction sections.

[0022] Preferably, the narrowed reaction section of the catalytic cracking reactor is in the form of a hollow truncated cone with an isosceles trapezoidal longitudinal section; the ratio of the inner diameter of the top cross section to the height of the narrowed 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 narrowed 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 narrowed reaction section to the total height of the catalytic cracking reactor is independently 0.15:1 to 0.8:1.

[0023] In one embodiment, the ratio of the inner diameter to the height of the pre-lifting zone of the catalytic cracking reactor is 0.02-0.4:1; and the ratio of its height to the total height of the catalytic cracking reactor is 0.01:1 to 0.2:1.

[0024] In one embodiment, the pre-lifting zone of the catalytic cracking reactor is connected to the reaction zone by a first connecting section, the longitudinal section of which is an isosceles trapezoid with an outward inclination angle α of 5-85° on the side of the isosceles trapezoid.

[0025] In one embodiment, the ratio of the inner diameter of the reactor outlet section to its height is 0.01-0.3:1, and the ratio of the height of the outlet section to the total height of the reactor is 0.05:1 to 0.5:1.

[0026] In one embodiment, the coke reactor is one or a combination of a bubbling fluidized bed or a turbulent fluidized bed.

[0027] This application also provides a catalytic cracking method coupled with reaction and coke formation, characterized in that the method includes:

[0028] 1) Preheated light oil is introduced from the bottom of the cracking reactor and comes into contact with the regenerated catalyst from the regenerator to carry out a catalytic cracking reaction, to obtain the first reaction oil and gas and the first spent catalyst. Part of the first spent catalyst is then transported to the coke reactor.

[0029] 2) The raw coke feedstock is introduced from the bottom of the raw coke reactor to contact a portion of the first catalyst to be produced for coking reaction, thereby obtaining the second reaction oil and gas and the second catalyst to be produced;

[0030] 3) After mixing the first and second reaction oil and gas, the mixture is introduced into a separation system to separate them, yielding dry gas, liquefied petroleum gas, cracked gasoline, and cracked heavy oil.

[0031] 4) The first and second batches of the spent catalyst are transported to the regenerator for coke burning and regeneration, and the resulting regenerated catalyst is transported to the cracking reactor for recycling.

[0032] In one embodiment, the light oil comprises gaseous hydrocarbons and light distillate oil; preferably, the light oil has properties that satisfy one, two, three, or four of the following indicators: density less than 860 kg / m³ at 20°C, carbon residue 0-0.5 wt%, total aromatics content 0%-30 wt%, and final boiling point less than 360°C.

[0033] In one embodiment, the conditions for the catalytic cracking reaction include: a reaction temperature of 510-750°C, a reaction time of 0.5-10 seconds, a catalyst-to-oil weight ratio of 10:1 to 50:1, a pre-lifting gas to feedstock weight ratio of 0.05:1 to 2.0:1, a catalyst density of 20-100 kg / m³, a linear velocity of 4-18 m / s, and a reaction pressure of 130-450 kPa.

[0034] In one embodiment, the method further includes introducing a C4 hydrocarbon fraction and / or a C5-C6 light gasoline fraction into the cracking reactor for catalytic cracking reaction;

[0035] Preferably, C4 hydrocarbons or C5-C6 light gasoline fractions are introduced downstream of the feed point of the light oil to the cracking reactor.

[0036] In one embodiment, the coke reactor is one or a combination of a bubbling fluidized bed or a turbulent fluidized bed;

[0037] Preferably, the conditions for the coking reaction include: a reaction temperature of 460-650℃, a reaction time of 1-20 seconds, a catalyst-to-oil weight ratio of 3:1 to 30:1, a pre-lifting gas to coking raw material weight ratio of 0.01:1 to 0.05:1, a linear velocity of 0.2-0.8 m / s, and a catalyst particle density of 300-700 kg / m³.

[0038] In one embodiment, the raw coke feedstock is pyrolysis heavy oil produced by the unit and secondary processed distillate oil, or a mixture thereof; preferably, the secondary processed distillate oil may be selected from one or more of catalytic cracking diesel, catalytic pyrolysis diesel, catalytic cracking slurry oil, catalytic pyrolysis slurry oil, coking gasoline, coking diesel, and coking wax oil; more preferably, the raw coke feedstock is pyrolysis heavy oil produced by the unit.

[0039] In one embodiment, the method is carried out in the catalytic cracking reaction-regeneration system described in this application.

[0040] In this application, the narrowed reaction section, especially the conical reaction section, of the cracking reactor in the system of the present invention is conducive to accelerating the exit of the reaction oil and gas from the reaction zone, shortening the reaction time, reducing catalyst backmixing, reducing the secondary conversion reaction of low-carbon olefins generated in the primary reaction, and improving the selectivity of low-carbon olefins.

[0041] In this application, by setting up a coking reactor, fuel oil can be mixed with the catalyst under low-temperature, oxygen-free fluidized bed conditions, and the coking reaction occurs in a reactor with bubbling bed or turbulent fluidized bed characteristics. This not only results in high coke selectivity but also ensures uniform distribution of coke on the catalyst, which is beneficial for uniform combustion within the regeneration system. In this application, the catalyst in the pyrolysis reactor has a low carbon content, retains high pyrolysis activity, and is at a moderate temperature, providing the most suitable reaction environment for the coking reactor.

[0042] In this application, the mixing of the first reaction oil and gas from high temperature with the second reaction oil and gas from low temperature can reduce the temperature of the reaction oil and gas entering the product separation device, making product recovery easier.

[0043] In this application, the coke generated by the raw coke reactor can be mixed with the coke generated by the reactor and enter the regeneration system. Under the action of high temperature and oxygen-enriched gas, the coke is fully burned and released heat to supply the heat required for the reaction without damaging the properties of the catalyst. This realizes the replenishment of coke source from the reaction system end and solves the heat balance problem of the catalytic cracking device.

[0044] When the method and system of this application are used in catalytic cracking reactions, the contact efficiency between the feedstock and the 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 by-products such as methane is low. This helps refineries transform, develop, and extend from oil refining to the production of chemical feedstocks, solving the problem of petrochemical feedstock shortages and improving the economic efficiency of refineries. Attached Figure Description

[0045] The accompanying drawings are provided to further illustrate the present application and form part of the specification. They are used together with the following detailed description to explain the present application, but do not constitute a limitation thereof. In the drawings:

[0046] Figure 1 A schematic diagram of a catalytic cracking reactor according to one embodiment of this application;

[0047] Figure 2 This is a schematic diagram of a catalytic cracking system according to one embodiment of the present application. Detailed Implementation

[0048] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present application will become clearer and more apparent.

[0049] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0050] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0051] Any specific numerical values ​​disclosed herein (including the endpoints of numerical ranges) are not limited to their exact values, but should be understood to also include values ​​close to the exact value, such as all possible values ​​within ±5% of the exact value. Furthermore, with respect to the disclosed numerical ranges, one or more new numerical ranges can be obtained by arbitrarily combining the endpoint values ​​of the range, the endpoint values ​​with specific point values ​​within the range, and the specific point values ​​themselves; these new numerical ranges should also be considered as specifically disclosed herein.

[0052] In this application, the terms "upstream" and "downstream" refer to the direction of reaction material flow. For example, when the reaction material flows from bottom to top, "upstream" refers to the position located at the bottom, while "downstream" refers to the position located at the top.

[0053] Unless otherwise stated, the terms used herein have the same meaning as commonly understood by those skilled in the art, and if a term is defined herein and its definition differs from the common understanding in the art, the definition herein shall prevail.

[0054] This application provides a catalytic cracking method coupled with reaction and coke formation, the method comprising:

[0055] 1) Preheated light oil is introduced from the bottom of the cracking reactor and comes into contact with the regenerated catalyst from the regenerator to carry out a catalytic cracking reaction, to obtain the first reaction oil and gas and the first spent catalyst. Part of the first spent catalyst is then transported to the coke reactor.

[0056] 2) The raw coke feedstock is introduced from the bottom of the raw coke reactor to contact a portion of the first catalyst to be produced for coking reaction, thereby obtaining the second reaction oil and gas and the second catalyst to be produced;

[0057] 3) After mixing the first and second reaction oil and gas, the mixture is introduced into a separation system to separate them, yielding dry gas, liquefied petroleum gas, cracked gasoline, and cracked heavy oil.

[0058] 4) The first and second batches of the spent catalyst are transported to the regenerator for coke burning and regeneration, and the resulting regenerated catalyst is transported to the cracking reactor for recycling.

[0059] Figure 2 A catalytic cracking reaction-regeneration system that can implement this method is shown. The catalytic cracking method of the present invention is further described below in conjunction with this catalytic cracking reaction-regeneration system.

[0060] The catalytic cracking reaction-regeneration system includes a catalytic cracking reaction system, a coking reaction system, and a regeneration system.

[0061] The catalytic cracking reaction system includes a cracking reactor 100, a first oil-to-oil separation device 201, and a first settling tank 200.

[0062] The cracking reactor 100 may be provided with a pre-lift gas inlet 101, one or more cracking feedstock inlets (e.g., a lower cracking feedstock inlet 102, a C4 hydrocarbon fraction and / or a C5-C6 light gasoline fraction inlet 105, etc.), a bottom catalyst inlet 103, and a top oil outlet 104. The oil outlet 104 of the cracking reactor is in fluid communication with the first oil separation device 201, so that the first reaction oil and gas and the first catalyst to be generated from the catalytic cracking reactor 100 are separated in the first oil separation device 201.

[0063] In one embodiment, the catalytic cracking reactor 100 comprises, from bottom to top:

[0064] Optional pre-lifting zone I,

[0065] Reaction zone II, comprising at least one diameter-reducing reaction section, wherein the diameter-reducing reaction section is a hollow cylinder with a generally circular cross-section and open at the bottom and top, and its inner diameter decreases continuously or discontinuously from bottom to top; and

[0066] Export Zone III

[0067] The optional pre-lifting 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 inlet 102 is provided on the optional pre-lifting zone and / or at the bottom of the reaction zone.

[0068] The inner diameter of the cross-section at the bottom of the reaction zone II is greater than or equal to the inner diameter of the cross-section of the optional pre-lifting zone I, and the inner diameter of the cross-section at the top is equal to or less than the inner diameter of the cross-section of the optional pre-lifting zone and the inner diameter of the cross-section of the outlet zone.

[0069] like Figure 1 As shown, the catalytic cracking reactor may include the pre-lifting zone I, which is located at the bottom of the catalytic cracking reactor and is used to pre-lift the catalyst, etc., entering the reactor. Figure 1 As shown, a catalyst inlet 103 is provided at the lower part of the pre-lifting zone I for introducing catalyst. The pre-lifting zone I can be a hollow cylindrical structure with an inner diameter to height ratio of 0.02-0.4:1 and a height to total reactor height ratio of 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 embodiments with a pre-lifting zone I, a pre-lifting medium can be introduced into the pre-lifting zone I through a pre-lifting medium pipeline 8. In embodiments with a pre-lifting zone I, at least one catalyst inlet 103 can also be provided at the bottom of the pre-lifting zone I for allowing the catalyst to enter the reactor through the pre-lifting zone I.

[0070] According to this application, the pre-lift zone I is not mandatory. For example, when the reaction zone II of the reactor of this application is used in series with other reactors, such as riser reactors, the reaction zone II can be directly connected to the outlet of the other reactor located upstream, without the need for the pre-lift zone I. In one embodiment, the catalytic cracking reactor may not include the pre-lift zone I. In this case, the bottom of the reaction zone II may be provided with at least one feed inlet 102 to facilitate the entry of raw materials into the catalytic cracking reactor. In embodiments where the pre-lift zone I is absent, the bottom of the reaction zone II may be provided with at least one catalyst inlet (not shown) to allow the catalyst to enter the reactor. Of course, the reaction zone II may also not be provided with a catalyst inlet, and the catalyst therein may be derived from the catalyst carried in the stream of other reactors. Both of these embodiments are within the scope of protection of this application.

[0071] like Figure 1 As shown, the catalytic cracking reactor may include a reaction zone II. A pre-lifting 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 feed inlet 102 are 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 210 of the reaction zone II is greater than or equal to the inner diameter of the cross-section of the pre-lifting 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-lifting zone I and the inner diameter of the cross-section of the outlet zone III.

[0072] In the catalytic cracking reactor provided in this application, the reaction zone II is a fluidized bed, preferably a combination of one or more of a transport fluidized bed, a turbulent fluidized bed, and a fast bed.

[0073] In one embodiment, the pre-lifting zone I and the reaction zone II are connected by a first transition section I-1. The longitudinal section of the first transition section I-1 can be an isosceles trapezoid, and the outward inclination angle α of the side of the isosceles trapezoid can be 5-85°, preferably 15-75°.

[0074] like Figure 1 As shown, the raw material inlet 9 can be located at the upper part of the pre-lifting zone I, in the first transition section I-1, or at the lower part of the reaction zone II. In particular, in an embodiment where the pre-lifting zone I is absent, the lower part of the reaction zone II can be provided with a raw material inlet 102 for feeding raw materials.

[0075] In one embodiment, the ratio of the bottom cross-sectional inner diameter 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.

[0076] like Figure 1 As shown, the reaction zone II includes at least one diameter-reducing reaction section, which is a hollow cylinder with a generally circular cross-section and open at the bottom and top, and whose inner diameter decreases continuously or discontinuously from bottom to top.

[0077] According to this application, "diameter reduction" refers to a decrease in the inner diameter in a discontinuous manner, such as a step-like or abrupt manner, or a continuous manner. As an example of "a diameter reduction segment with a discontinuous decrease in inner diameter from bottom to top", a column composed of two or more segments with decreasing inner diameters can be cited.

[0078] As an example, the reaction zone II can be a cylindrical shape comprising one or more hollow truncated conical segments, or a cylindrical shape comprising two or more hollow cylindrical segments. According to this application, when the reaction zone comprises two or more reduced-diameter reaction segments, each reduced-diameter reaction segment can have the same or different heights; this application does not impose strict limitations on this.

[0079] 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.

[0080] In one implementation, such as Figure 1 As shown, the reaction zone II includes a narrowed reaction section, which is in the shape of a hollow truncated cone with an isosceles trapezoidal longitudinal section; the inner diameter D of its apex cross-section is... 220 The height h of the diameter-reducing reaction section II The ratios are independently 0.005-0.3:1, and the inner diameter D of the bottom cross-section is... 210 The height h of the diameter-reducing reaction section II The ratios of the two sides are independently 0.015-0.25:1, and the inner diameter D of the bottom cross-section is... 210 With 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 reactor 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...210 The ratio of the height h1 of the reactor 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 narrowing 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 h of the reaction zone II is... II The ratio of the reactor's height to its total height h 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 top cross-section of the narrowed reaction section 100 is... 210 The height is 0.2-5 meters, preferably 0.4-3 meters. In one embodiment, the total height h of the reaction zone II is... II It can be about 2-50 meters, preferably about 5-40 meters, and more preferably about 8-20 meters.

[0081] In the catalytic cracking reactor of this application, the large bottom space of the narrowed reaction section, especially the conical reaction section, can effectively increase the catalyst density in the reactor, thereby significantly increasing the ratio of catalyst to reactants in the reactor, enhancing the primary cracking reaction of the reactants, improving not only the reaction conversion rate but also the yield of low-carbon olefins. Moreover, the narrowed structure of the narrowed reaction section, especially the conical reaction section, facilitates the acceleration of the reaction oil and gas leaving the reaction zone, shortens the reaction time, and reduces catalyst backmixing, which helps to reduce the secondary conversion reaction of low-carbon olefins generated in the primary reaction and improves the selectivity of low-carbon olefins.

[0082] In the catalytic cracking reactor provided in this application, the reactor may be provided with one or more feed inlets, such as one, two or more feed inlets. These feed inlets may be independently located at the outlet end of the pre-lifting zone I or at the bottom of the reaction zone II. More preferably, the multiple feed inlets are independently located at the same height or different heights within the reaction zone II. Thus, feedstocks with different properties can be fed through different feed inlets.

[0083] like Figure 1 As shown, the catalytic cracking reactor may include an outlet zone III. In one embodiment, the outlet zone III may be a hollow cylindrical shape, with its cross-sectional inner diameter and height h. III The ratio is 0.01-0.3:1, and the height h of the exit area is... III The ratio of the height 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.

[0084] As previously stated, 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.

[0085] 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 can be connected by a third transition section (not shown). The longitudinal section of this third transition section can be an isosceles trapezoid, and the outward inclination angle of the sides of the isosceles trapezoid can be 5-85°, preferably 15-75°.

[0086] The outlet end 104 of the outlet zone III can be open or directly connected to the inlet of the first oil separation device 201, such as a cyclone separator.

[0087] The first oil-catalyst separation device 201 is used to separate the reaction products and catalyst from the oil in the catalytic cracking reactor 100. The oil-catalyst separation device 201 is connected to the outlet end 104 of the catalytic cracking reactor.

[0088] The first settling tank 200 is used to allow the catalyst separated by the first oil-catalyst separator 201 to settle and enter the settling section 205 at the bottom of the settling tank. The first settling tank 200 is configured to collect the first unprocessed catalyst separated in the first oil-catalyst separator 201, and is provided with a first unprocessed catalyst outlet 206 and a second unprocessed catalyst outlet 208. The settling section 205 at the bottom of the first settling tank 200 can be circulated with fluidizing gas through inlet 207 to fluidize the catalyst at the bottom of the settling tank, facilitating the outflow of the first catalyst. A portion of the first catalyst can flow through the first unprocessed catalyst outlet 206 into the coking reactor 300 for coking reaction via pipeline, and the remaining portion can flow through the second unprocessed catalyst outlet 208 into the regeneration system for regeneration. The proportion of unprocessed catalyst entering the coking reactor 300 can be adjusted as needed; for example, the unprocessed catalyst entering the coking reactor 300 can account for 5%-50%, based on the total weight of all the first unprocessed catalyst.

[0089] In one embodiment, the first oil separation device 201 is housed inside the first settling tank 200, and the first settling tank 200 is arranged coaxially with the catalytic cracking reactor 100. Of course, the first settling tank 200 and the catalytic cracking reactor 100 can be arranged side by side at different heights.

[0090] The reaction oil and gas (i.e. reaction products) obtained by the first oil separation device 201 are collected in the gas collection chamber 202 and then transported through pipeline 203 to the subsequent reaction product separation device (not shown) for further separation.

[0091] In one embodiment, the light oil used in the catalytic cracking reactor 100 comprises gaseous hydrocarbons and light distillate oil. The light oil has properties that satisfy one, two, three, or four of the following indicators: density less than 860 kg / m³ at 20°C, carbon residue 0-0.5 wt%, total aromatics content 0%-30 wt%, and final boiling point less than 360°C.

[0092] In one embodiment, the gaseous hydrocarbon may be selected from one or more of saturated liquefied petroleum gas (LPG), unsaturated LPG, and C4 fractions; the light distillate oil includes distillate oils of petroleum hydrocarbons, oxygenated compounds, biomass or waste plastics with a distillation range of 25–360°C; the petroleum hydrocarbon may be selected from one or more of primary processed straight-run naphtha, straight-run kerosene, and straight-run diesel; and a mixture of one or more of secondary processed topping oil, residue oil, hydrocracked light naphtha, pentane oil, coking gasoline, Fischer-Tropsch synthetic oil, catalytic cracked light gasoline, hydrotreated gasoline, and hydrotreated diesel.

[0093] In one embodiment, the catalyst comprises, on a dry basis and based on the dry weight of the catalyst, 1-50 wt%; 5-99 wt% of inorganic oxides; and 0-70 wt% of clay. The zeolite comprises mesoporous zeolite and optionally macroporous zeolite, wherein the mesoporous zeolite is selected from ZSM series zeolites, ZRP zeolite, and any combination thereof; and the macroporous zeolite is selected from rare earth Y-type zeolite, rare earth hydrogen Y-type zeolite, ultrastable Y-type zeolite, and high-silica Y-type zeolite, and any combination thereof. On a dry basis, the mesoporous zeolite accounts for 10-100 wt% of the total weight of the zeolite, preferably 50-90 wt%.

[0094] In this application, the terms mesoporous zeolite and macroporous zeolite are defined according to conventional definitions in the art, namely, the average pore size of mesoporous zeolite is about 0.5-0.6 nm, and the average pore size of macroporous zeolite is about 0.7-1.0 nm.

[0095] As an example, the macroporous zeolite may be selected from one or more of rare earth Y (REY) type zeolite, rare earth hydrogen Y (REHY) type zeolite, ultrastable Y type zeolite obtained by different methods, and high-silica Y type zeolite. The mesoporous zeolite may be selected from zeolites with an MFI structure, such as ZSM series zeolites and / or ZRP zeolite. Optionally, the above-mentioned mesoporous zeolites may be modified with non-metallic elements such as phosphorus and / or transition metal elements such as iron, cobalt, and nickel. A more detailed description of ZRP zeolite can be found in US Patent 5,232,675A. The ZSM series zeolites are preferably selected from one or more mixtures of ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48, and other zeolites with similar structures. A more detailed description of ZSM-5 can be found in US Patent 3,702,886A.

[0096] According to this application, the inorganic oxide, as a binder, is preferably silicon dioxide (SiO2) and / or aluminum oxide (Al2O3). The clay, as a matrix (i.e., carrier), is preferably kaolin and / or hydrous kaolin.

[0097] In one embodiment, the conditions for the catalytic cracking reaction include: a reaction temperature of 550-750°C, a reaction time of 0.5-10 seconds, a catalyst-to-oil weight ratio of 10:1 to 50:1, a pre-lifting gas to feedstock weight ratio of 0.05:1 to 2.0:1, a catalyst density of 20-100 kg / m³, a linear velocity of 4-18 m / s, and a reaction pressure of 130-450 kPa.

[0098] In one embodiment, the light oil preheating temperature of the catalytic cracking reactor is 280-480°C, preferably 300-400°C.

[0099] In one embodiment, the feedstock oil is introduced into the cracking reactor at one location, or at more than one identical or different locations.

[0100] In one embodiment, the method preferably further includes: introducing a C4 hydrocarbon fraction and / or a C5-C6 light gasoline fraction into the cracking reactor for catalytic cracking reaction.

[0101] In this application, the C4 hydrocarbon fraction refers to low-molecular-weight hydrocarbons existing in gaseous form at room temperature and pressure, with C4 fraction as the main component. This includes alkanes, alkenes, and alkynes with four carbon atoms in their molecules. It can include gaseous hydrocarbon products rich in C4 hydrocarbon fractions produced by the method of this invention (e.g., liquefied petroleum gas), or gaseous hydrocarbons rich in C4 hydrocarbon fractions produced by other devices, with the C4 hydrocarbon fraction produced by the method of this invention being preferred. The C4 hydrocarbon fraction is preferably a C4 hydrocarbon fraction rich in olefins, and the content of C4 olefins can be greater than 50% by weight, preferably greater than 60% by weight, and more preferably greater than 70% by weight.

[0102] In this application, the C5-C6 light gasoline fraction may include cracked gasoline produced by the method of the present invention, or gasoline fractions produced by other devices, such as at least one C5-C6 fraction selected from catalytic cracked gasoline, catalytically cracked gasoline, straight-run gasoline, coking gasoline, thermally cracked gasoline, thermally cracked gasoline, and hydrotreated gasoline. The C5-C6 light gasoline is preferably an olefin-rich fraction, wherein the olefin content is greater than 50% by weight, preferably greater than 60% by weight.

[0103] In one embodiment, the C4 hydrocarbon or C5-C6 light gasoline fraction is introduced at one or more locations downstream of the feed location of the light oil to the cracking reactor.

[0104] In this application, the coking reaction system includes a coking reactor 300, a second oil separation device 401, and a second settling tank 400.

[0105] The coke reactor 300 is provided with a pre-lift gas inlet 301 at the bottom, a catalyst inlet 303, a coke raw material inlet 302 at the bottom, and an oil outlet 304 at the top. The catalyst inlet 303 of the coke reactor is in fluid communication with the first unprocessed catalyst outlet 206 of the first settling tank, so that at least a portion of the first unprocessed catalyst enters the coke reactor 300. The oil outlet 304 of the coke reactor is in fluid communication with the second oil separation device 401, so that the second reaction oil gas and the second unprocessed catalyst from the coke reactor are separated in the second oil collection device 401.

[0106] The second settling tank 400 is configured to collect the second spent catalyst separated in the second oil-catalyst separation device 401, and is provided with a third spent catalyst outlet 406. A stripping section 405 is provided at the lower part of the second settling tank 400 for stripping the catalyst therein to recover the reaction oil and gas. Stripping gas is introduced through the stripping gas inlet 407 for stripping treatment.

[0107] The reaction oil and gas (i.e. reaction products) obtained by the second oil separation device 401 are collected in the gas collection chamber 402 and then transported through pipeline 403 to the subsequent reaction product separation device (not shown) for further separation.

[0108] In this application, the coke reactor can be one of a bubbling fluidized bed or a turbulent fluidized bed, or a combination thereof.

[0109] In one embodiment, the second oil separation device 401 is housed inside the second settling tank 400, and the second settling tank 400 is arranged coaxially with the coke reactor 300. Of course, the second settling tank 400 and the coke reactor 300 can be arranged side by side at different heights.

[0110] In one embodiment, the conditions for the coking reaction include: a reaction temperature of 460-560°C, a reaction time of 1-20 seconds, a catalyst-to-oil weight ratio of (3-30):1, a pre-lifting gas to coking feedstock weight ratio of (0.01-0.5):1, a linear velocity of 0.2 m / s-1.2 m / s, and a catalyst particle density of 300 kg / m³-700 kg / m³. In one embodiment, the pre-lifting gas is selected from water vapor, nitrogen, dry gas, rich gas, or C4 fraction or mixtures thereof.

[0111] In one embodiment, the raw coke feedstock is plant-produced pyrolysis heavy oil and secondary processed distillate oil, or a mixture thereof. Preferably, the secondary processed distillate oil may be selected from one or more of catalytic cracking diesel, catalytic pyrolysis diesel, catalytic cracking slurry oil, catalytic pyrolysis slurry oil, coking gasoline, coking diesel, and coking wax oil. More preferably, the raw coke feedstock is plant-produced pyrolysis heavy oil. In one embodiment, the feed rate of the raw coke feedstock is 10-50 wt% of the feed rate to the catalytic cracking reactor.

[0112] In this application, a regeneration system is used to regenerate the spent catalyst (including a first spent catalyst and a second spent catalyst). The regeneration system includes a regenerator 500 for regenerating the spent catalyst, with an oxygen-containing gas inlet 501 at the bottom, two spent catalyst inlets 505 and 507, a regenerated catalyst outlet 506, and a flue gas outlet 504 at the top. The two spent catalyst inlets 505 and 507 are respectively connected to the second spent catalyst outlet 208 and the third spent catalyst outlet 406, and the regenerated catalyst outlet 506 is connected to the regenerated catalyst inlet 103. Thus, the spent catalyst enters the regenerator 500 for regeneration and is then recycled back to the catalytic cracking reactor 100.

[0113] Oxygen-containing gas from oxygen-containing gas inlet 501 enters regenerator 500 after passing through gas distributor 502, where it comes into contact with the catalyst to be regenerated and undergoes a complete combustion reaction, releasing heat completely. The regenerated catalyst is sent to catalytic cracking reactor 100 for recycling through regenerated catalyst outlet 506 and catalyst inlet 103. The regenerated flue gas is sent to the subsequent energy recovery system through cyclone separator 503 to recover the entrained catalyst, and then through flue gas outlet 504.

[0114] The reaction product separation apparatus used in this application can be equipped with a reaction product inlet, a dry gas outlet, a liquefied petroleum gas (LPG) outlet, a cracked gasoline outlet, and a cracked heavy oil outlet, for separating the reaction products into dry gas, LPG, cracked gasoline, and cracked heavy oil according to their distillation range. The dry gas and LPG are then further separated by a gas separation device to obtain methane, ethylene, propylene, and mixed C4 components, etc., and the cracked gasoline is further separated to obtain C5-C6 light gasoline. The methods for separating ethylene, propylene, etc., from the reaction products are similar to conventional techniques in the art, and this invention does not limit these methods and will not describe them in detail here.

[0115] In one embodiment, the first oil separation device used in this application is a settling device arranged coaxially or at different heights with the catalytic cracking reactor.

[0116] In one embodiment, the second oil-separating device used in this application is a settling device arranged coaxially or at different heights with the coke reactor.

[0117] In the catalytic cracking system of this application, there can be one or more catalytic cracking reactors. These reactors can be a combination of one catalytic cracking reactor from this application with other existing catalytic cracking reactors, or a combination of multiple catalytic cracking reactors from this application. These reactors can be connected in parallel and connected to an oil-solvent separation unit.

[0118] In the catalytic cracking system provided in this application, the settler, oil-electrode separation device, regenerator, and reaction product separation device can all be equipment well known to those skilled in the art, and the connection methods between these devices can also be carried out in accordance with methods known in the art. For example, the oil-electrode separation device may include a cyclone separator and an outlet rapid separator.

[0119] The catalytic cracking method and system of this application can efficiently produce chemical feedstocks such as ethylene and propylene from light petroleum hydrocarbons. This not only fundamentally solves the problem of heat balance, but also reduces the damage to catalysts and regeneration systems caused by traditional fuel injection methods, saving catalyst costs and helping refineries transform, develop and extend from oil refining to chemical feedstock production. It solves the problem of petrochemical feedstock shortage and improves the economic benefits of refineries.

[0120] The present application will be further described below with reference to the preferred embodiments shown in the accompanying drawings, but this does not limit the present application.

[0121] Figure 2 Preferred embodiments of the catalytic cracking reaction system of this application are provided.

[0122] The pre-lift gas enters the cracking reactor 100 from the bottom through the pre-lift gas inlet 101. The high-temperature regenerated catalyst of the self-regenerator enters the lower part of the cracking reactor 100 through the catalyst inlet 103, mixes with the pre-lift gas and moves upward, and comes into contact with the feed oil from the feed oil inlet 102 to undergo a catalytic cracking reaction. The carbonized catalyst and the reaction-generated oil and gas flow upward and enter the oil-catalyst separation device 201 through the outlet 104.

[0123] The reaction oil and gas separated by the oil-agent separation device 201 enters the gas collection chamber 202 and is introduced into the product separation system through the oil and gas pipeline 203; the separated coke-containing catalyst enters the settling section 205, part of the reactant enters the regenerator 500, and part enters the coke reactor 300.

[0124] The pre-lift gas enters the coking reactor 300 from the bottom through the pre-lift gas inlet 301. The catalyst to be generated from the settling section 205 enters the lower part of the coking reactor 300 through the catalyst inlet 303, mixes with the pre-lift gas and moves upward. It then comes into contact with the coking feedstock from the fuel oil inlet 302 and enters the coking reactor together to undergo a coking reaction. The carbonized catalyst and the reaction-generated oil and gas flow upward and enter the oil-catalyst separation device 401 through the outlet end 304.

[0125] The reaction oil and gas separated by the oil-gas separator 401 enters the gas collection chamber 402 and is introduced into the product separation system via the oil and gas pipeline 403; the separated coke-containing catalyst enters the stripping section 405 and is stripped by steam from the stripping gas inlet 407 before entering the regenerator 500.

[0126] Oxygen-containing gas from oxygen-containing gas inlet 501 enters regenerator 500 after passing through gas distributor 502. It comes into contact with coke-laden catalyst from catalytic cracking reactor and coke reactor and undergoes a complete combustion reaction, releasing heat completely. The regenerated catalyst is then sent to catalytic cracking reactor for recycling. The regenerated flue gas passes through cyclone separator 503 to recover the entrained catalyst, and then through flue gas outlet 504 to the subsequent energy recovery system.

[0127] Example

[0128] The following examples will further illustrate this application, but do not limit it. The catalyst used in the experiment was an industrial catalyst, commercially known as NCC. The feedstock for the cracking reaction was Yanshan straight-run naphtha, taken from the atmospheric and vacuum distillation unit of Yanshan Petrochemical. The raw coke feedstock was Anqing oil slurry, taken from the catalytic cracking unit of Anqing Petrochemical. The properties of the two feedstocks are shown in Table 1.

[0129] Example 1

[0130] exist Figure 2 The system was tested, and the structure of the catalytic cracking reactor used was as follows:

[0131] The reactor has a total height of 10 meters, including a pre-lifting zone of 2 meters and an inner diameter of 0.2 meters; a reaction zone of 5 meters with an inner diameter of 0.2 meters at the top and 0.3 meters at the bottom; and an outlet zone of 3 meters with an inner diameter of 0.2 meters.

[0132] The structure of the coke reactor is as follows:

[0133] The coke reactor is a riser reactor with a total height of 5 meters and an inner diameter of 0.4 meters.

[0134] A cracking experiment of straight-run naphtha was conducted in a catalytic cracking reactor. Preheated feedstock was introduced from the bottom of the reactor and contacted with regenerated catalyst from the regenerator. The catalytic cracking reaction proceeded from bottom to top, yielding an oil-catalyst mixture of reaction products and the spent catalyst. This mixture entered a cyclone separator from the reactor outlet, where the reaction products and spent catalyst were rapidly separated. The reaction products were collected after cooling. The spent catalyst entered a stripping section under gravity, where adsorbed hydrocarbon products were stripped from the catalyst by steam. A portion of the stripped catalyst entered a coking reactor for coking, while the remaining catalyst directly entered the regenerator for regeneration. The proportion of spent catalyst entering the coking reactor was 14%, based on the total weight of all spent catalyst.

[0135] Anqing oil slurry is fed into the coking reactor, where it contacts the catalyst to be recycled and undergoes a coking reaction, yielding a mixture of reaction products and carbonized catalyst. This mixture exits the coking reactor into a cyclone separator, where the reaction products and carbonized catalyst are rapidly separated. The reaction products are then collected after cooling. The carbonized catalyst, under gravity, enters the stripping section, where steam strips the adsorbed hydrocarbon products from the catalyst. The stripped catalyst then enters the regenerator.

[0136] Part of the spent catalyst from the catalytic cracking reactor and the charred catalyst from the coke reactor enter the regenerator and are regenerated by contact with air. The regenerated catalyst is then returned to the catalytic cracking reactor for recycling. Operating conditions and product distribution are listed in Table 2.

[0137] As can be seen from the results in Table 2, the methane yield was 9.78%, the ethylene yield was 25.07 wt%, the propylene yield was 25.12 wt%, the coke yield was 6.40%, the total selectivity for ethylene and propylene was 57.56%, and the methane selectivity was 11.22%.

[0138] Comparative Example 1

[0139] According to similar Figure 2 The system was tested in accordance with Example 1, except that Comparative Example 1 did not include a coking reaction system, and the catalytic cracking reaction system was directly connected to the regenerator, i.e., the catalyst was regenerated as follows:

[0140] The spent catalyst enters the stripping section of the settler under gravity, where water vapor strips the hydrocarbon products adsorbed on the catalyst. The stripped catalyst then enters the regenerator for regeneration through contact with air. The regenerated catalyst is then returned to the catalytic cracking reactor for recycling. Operating conditions and product distribution are listed in Table 2.

[0141] The results in Table 2 show that the methane yield was 10.11%, the ethylene yield was 24.15 wt%, the propylene yield was 24.22 wt%, the coke yield was 3.69%, the total selectivity for ethylene and propylene was 57.49%, and the methane selectivity was 12.02%. The coke yield in this comparative example was low, indicating insufficient coking, which was insufficient to maintain the thermal equilibrium of the reaction.

[0142] As can be seen from the results of the above embodiments, the catalytic cracking reaction system of this application can not only reduce the methane yield and improve the selectivity of ethylene and propylene, but also generate coke with high selectivity, providing a heat source for the regenerator from the perspective of the reaction system, without affecting the regeneration system.

[0143] In the description of this application, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship in the working state of this application. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0144] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0145] The present application has been described above with reference to preferred embodiments; however, these embodiments are merely exemplary and illustrative. Various substitutions and modifications can be made to the present application based on these embodiments, all of which fall within the protection scope of the present application.

[0146] Table 1 Properties of pyrolysis reaction feedstock and coke feedstock

[0147] Straight-run naphtha Anqing Oil Slurry <![CDATA[Density at 20 °C, kg / m 3 > 752.5 1068.6 70℃ refractive index 1.6361 <![CDATA[Viscosity at 100 °C, millimeters 2 / second]]> 11.5 Residual char, % (by weight) 0 4.79 Carbon content, % (by weight) 87.47 91.22 Hydrogen content, % (by weight) 14.53 8.06 Sulfur content, % (by weight) 0.014 0.331 Nitrogen content, mg / kg 1.2 2100 Basic nitrogen, mg / kg / 86 Distillation range, °C 5% (by volume) / 364.5 10% (by volume) 90.9 373.2 30% (by volume) 121.7 400.6 50% (by volume) 145.8 425.6 70% (by volume) 167.3 464.8 95% (by volume) 197.5 /

[0148] Table 2. Operating conditions and results of Example 1 and Comparative Example 1

[0149] Example 1 Comparative Example 1 Pyrolysis reactor conditions Pyrolysis reactor outlet temperature, °C 670 670 Catalyst to feedstock weight ratio 30：1 30：1 Reaction time, seconds 2.1 2 Water vapor to feed weight ratio 0.3 0.3 Coke reactor conditions Outlet temperature of the coke reactor, °C 550 Catalyst to fuel oil feed weight ratio 10 Reaction time, seconds 5 Water vapor to fuel oil feed weight ratio 0.20 The percentage of raw coke feed to the total feed to the pyrolysis reactor. 35 Regenerator conditions Temperature inside the regenerator, °C 720 720 Product yield, by weight % dry air 39.95 40.03 Methane 9.78 10.11 ethylene 25.07 24.15 Liquefied gas 38.90 38.16 Among them, propylene 25.12 24.22 Cracked gasoline 12.81 15.86 Cracked heavy oil 2.04 2.26 coke 6.40 3.69 total 100.00 100.00 Methane selectivity, % 11.22 12.02 Total selectivity of ethylene and propylene, % 57.56 57.49

Claims

1. A catalytic cracking reaction-regeneration system, comprising a catalytic cracking reaction system, a coking reaction system, and a regeneration system. in, The catalytic cracking reaction system includes a catalytic cracking reactor, a first oil-to-fuel separation device, and a first settling tank; The catalytic cracking reactor is provided with a pre-lift gas inlet at the bottom, a catalyst inlet, one or more cracked feedstock inlets, and an oil outlet at the top; the oil outlet of the catalytic cracking reactor is in fluid communication with the first oil separation device, so that the first reaction oil and gas and the first catalyst to be generated from the catalytic cracking reactor are separated in the first oil separation device; The first settling device is configured to collect the first catalyst to be generated separated in the first oil-catalyst separation device, and is provided with a first catalyst to be generated outlet and a second catalyst to be generated outlet; The coking reaction system includes a coking reactor, a second oil-separation device, and a second settling tank. The coke reactor is provided with a pre-lift gas inlet at the bottom, a catalyst inlet, a coke raw material inlet at the bottom, and an oil agent outlet at the top; wherein, the catalyst inlet of the coke reactor is fluidly connected to the outlet of the first catalyst to be generated in the first settling tank, so that at least a portion of the first catalyst to be generated enters the coke reactor; the oil agent outlet of the coke reactor is fluidly connected to the second oil agent separation device, so that the second reaction oil gas and the second catalyst to be generated from the coke reactor are separated in the second oil agent separation device; wherein the coke reactor is one of a bubbling fluidized bed or a turbulent fluidized bed or a combination thereof; The second settling device is configured to collect the second catalyst to be generated separated in the second oil-separation device, and is provided with a third catalyst to be generated outlet; The regeneration system is provided with a catalyst inlet and a catalyst outlet; wherein, the catalyst inlet is fluidly connected to the second catalyst outlet of the first settling tank and the third catalyst outlet of the second settling tank, so that the remaining first and second catalysts enter the regeneration system for regeneration; the catalyst outlet is also fluidly connected to the catalyst inlet of the catalytic cracking reactor, so that the catalyst enters the catalytic cracking reactor.

2. The catalytic cracking reaction-regeneration system according to claim 1, wherein, The catalytic cracking reactor comprises, from bottom to top: Optional pre-promotion area; The reaction zone includes at least one diameter-reducing reaction section, which is a hollow cone with a generally circular cross-section and open at both the bottom and top, its inner diameter decreasing continuously or discontinuously from bottom to top; and Export zone; The optional pre-lifting zone is connected to the bottom of the reaction zone, the top of the reaction zone is connected to the outlet zone, and at least one raw material inlet is provided on the optional pre-lifting zone and / or at the bottom of the reaction zone. The inner diameter of the cross-section at the bottom of the reaction zone is greater than or equal to the inner diameter of the cross-section of the optional pre-lift zone, and the inner diameter of the cross-section at the top is equal to or less than the inner diameter of the cross-section of the optional pre-lift zone and the inner diameter of the cross-section of the outlet zone; the regenerated catalyst inlet is provided at the bottom of the reaction zone and / or the optional pre-lift zone.

3. The catalytic cracking reaction-regeneration system according to claim 1, wherein, The ratio of the inner diameter of the bottom cross-section of the reaction zone of the catalytic cracking reactor 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.

4. The catalytic cracking reaction-regeneration system according to claim 1, characterized in that, The reaction zone of the catalytic cracking reactor includes 1-3 narrowing reaction sections.

5. The catalytic cracking reaction-regeneration system according to claim 4, characterized in that, The narrowed reaction section of the catalytic cracking reactor is in the form of a hollow truncated cone with an isosceles trapezoidal longitudinal section. The ratio of the inner diameter of the top cross section to the height of the narrowed reaction section is 0.005-0.3:1, the ratio of the inner diameter of the bottom cross section to the height of the narrowed reaction section is 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 greater than 1.2 and less than or equal to 10. The ratio of the height of the narrowed reaction section to the total height of the catalytic cracking reactor is 0.15:1 to 0.8:

1.

6. The catalytic cracking reaction-regeneration system according to claim 2, characterized in that, The ratio of the inner diameter to the height of the pre-lifting zone of the catalytic cracking reactor is 0.02-0.4:1; the ratio of its height to the total height of the catalytic cracking reactor is 0.01:1 to 0.2:

1.

7. The catalytic cracking reaction-regeneration system according to claim 6, characterized in that, The pre-lift zone of the catalytic cracking reactor 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 degrees. o .

8. The catalytic cracking reaction-regeneration system according to claim 2, characterized in that, The ratio of the inner diameter to the height of the cross-section 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.

9. A catalytic cracking method coupled with reaction and coke formation, characterized in that, The method includes: 1) Preheated light oil is introduced from the bottom of the catalytic cracking reactor and comes into contact with the regenerated catalyst from the regenerator to carry out a catalytic cracking reaction, to obtain a first reaction oil gas and a first spent catalyst. A portion of the first spent catalyst is transported to the coke reactor. The light oil includes gaseous hydrocarbons and light distillate oil. 2) The raw coke feedstock is introduced from the bottom of the raw coke reactor to contact a portion of the first catalyst to be produced for the raw coke reaction, to obtain the second reaction oil and gas and the second catalyst to be produced; wherein the raw coke reactor is one of a bubbling fluidized bed or a turbulent fluidized bed or a combination thereof; 3) After mixing the first and second reaction oil and gas, the mixture is introduced into a separation system for separation. 4) The first and second spent catalysts are fed to a regenerator for coke burn-off regeneration, and the resulting regenerated catalyst is fed back to the catalytic cracking reactor for recycling. The method is carried out in the catalytic cracking reaction-regeneration system according to any one of claims 1-8.

10. The method according to claim 9, characterized in that, The light oil has properties that meet one, two, three, or four of the following criteria: density less than 860 kg / m³ at 20°C, carbon residue 0-0.5% by weight, total aromatics content 0%-30% by weight, and final boiling point less than 360°C.

11. The method according to claim 9, characterized in that, The conditions for the catalytic cracking reaction include: a reaction temperature of 510-750℃, a reaction time of 0.5-10 seconds, a catalyst-to-oil weight ratio of 10:1 to 50:1, a pre-lift gas to feedstock weight ratio of 0.05:1 to 2.0:1, and a catalyst density of 20. 100 kg / m³, linear velocity of 4-18 m / s, reaction pressure of 130-450 kPa.

12. The method according to claim 9, characterized in that, The method further includes separating the C4 hydrocarbon fraction and / or C5 hydrocarbon fraction. The C6 light gasoline fraction is introduced into the catalytic cracking reactor for catalytic cracking reaction.

13. The method according to claim 12, characterized in that, A C4 hydrocarbon fraction or C5 hydrocarbon fraction is introduced downstream of the feed point of the catalytic cracking reactor where light oil is introduced. C6 light gasoline fraction.

14. The method according to claim 9, characterized in that, The conditions for the coking reaction include: a reaction temperature of 460-650℃, a reaction time of 1-20 seconds, a catalyst-to-oil weight ratio of 3:1 to 30:1, a pre-lifting gas to coking raw material weight ratio of 0.01:1 to 0.05:1, a linear velocity of 0.2-0.8 m / s, and a catalyst particle density of 300-700 kg / m³.

15. The method according to claim 9, characterized in that, The raw coke feedstock is self-produced cracked heavy oil or secondary processed distillate oil, or a mixture thereof, wherein the secondary processed distillate oil is selected from one or more of the following: catalytic cracked diesel oil, catalytic cracked diesel oil, catalytic cracked slurry oil, catalytic cracked slurry oil, coking gasoline, coking diesel oil, and coking wax oil.

16. The method according to claim 15, characterized in that, The raw coke feedstock is pyrolyzed heavy oil produced by the unit itself.

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