RU2775469C1 - Method for production of high-octane gasoline of catalytic cracking - Google Patents

Abstract

FIELD: oil industry.

SUBSTANCE: present invention relates to a method for the production of catalytic cracking gasoline, which provides for stages, at which 1): i) heavy feed oil is sprayed into an elevator reactor through the first nozzle, the first catalytic cracking catalyst is injected into the elevator reactor at the first injection point located below the first nozzle, and heavy feed oil is subjected to a catalytic cracking reaction to obtain the first reaction product; ii) hydrogenated recycled gas oil is sprayed into the elevator reactor used at the stage i) through the second nozzle, the second catalytic cracking catalyst is injected into the elevator reactor at the second injection point located below the second nozzle, and hydrogenated recycled gas oil is subjected to a catalytic cracking reaction to obtain the second reaction product; iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytic cracking gasoline and light recycled catalytic cracking gas oil; iv) light recycled catalytic cracking gas oil or its fraction is hydrogenated to obtain a hydrogenated product; and v) the hydrogenated product in the form of hydrogenated recycled gas oil is returned to the stage ii), wherein, in the direction of the height of the elevator reactor, the second nozzle is located above the first nozzle, and the second injection point occupies a position between the first nozzle and the second nozzle; or 2): i) heavy feed oil is sprayed into a primary elevator reactor through the first nozzle, the first catalytic cracking catalyst is injected into the primary elevator reactor at the first injection point located below the first nozzle, and heavy feed oil is subjected to a catalytic cracking reaction to obtain the first reaction product; ii) hydrogenated recycled gas oil is sprayed into a secondary elevator reactor through the second nozzle, the second catalytic cracking catalyst is injected into the secondary elevator reactor at the second injection point located below the second nozzle, and hydrogenated recycled gas oil is subjected to a catalytic cracking reaction to obtain the second reaction product; iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytic cracking gasoline and light recycled catalytic cracking gas oil; (iv) light recycled catalytic cracking gas oil or its fraction is hydrogenated to obtain a hydrogenated product; and (v) the hydrogenated product in the form of hydrogenated recycled gas oil is returned to the stage ii), wherein the second reaction product is fed to the upper part of the middle of the primary elevator reactor, where it is mixed with the first reaction product. The present invention also relates to a catalytic cracking system for implementing this method.

EFFECT: creation of optimized reaction conditions for hydrogenated recycled gas oil and heavy feed oil and, as a result, obtaining a high yield of high-octane gasoline.

16 cl, 7 ex, 6 tbl, 4 dwg

Description

Link to related applications

The present application claims priority according to PRC Patent Application No. 201711010110.6 filed October 25, 2017 with the PRC Patent Office, entitled "Process for Producing High-Octane Gasoline", and priority according to PRC Patent Application No. 201711016169.6 filed October 25, 2017 with the Patent Office PRC and entitled "Method and system for catalytic cracking using double riser reactors", the contents of which are incorporated herein by reference in their entirety.

The field of technology to which the present invention relates

The present application relates to the field of catalytic cracking technology and, in particular, to a method for producing high-octane catalytically cracked gasoline.

Background of the Invention

With the increase in the use of heavy oil and the rapid growth in demand for light oil products in the PRC, the development of catalytic cracking technologies for converting heavy oil into light oil products has accelerated. However, a problem inevitably arises in that catalytic cracking produces diesel fuel (also referred to as "light cycle oil (LRG)"), usually having a relatively low quality, high density, high aromatic content and low cetane number. Thus, it is difficult to meet the increasingly stringent specifications of diesel fuel even by hydrotreating diesel fuel technology. The problem of processing light cycle oil from catalytic cracking is becoming more and more serious. The next problem is the long-term storage of final gasoline in the PRC, where catalytically cracked gasoline makes up 80% of the final gasoline. Thus, a new way to solve the above problems may be to maximize the production of high-octane gasoline by a catalytic cracking process that can produce high-octane gasoline without producing light cycle oil.

U.S. Patent No. 4,585,545 A discloses a catalytic conversion process comprising the step of subjecting crude catalytically cracked light cycle oil to hydrotreatment to produce hydrogenated light cycle oil and subsequent catalytic cracking to produce monocyclic aromatic enriched gasoline.

PRC Patent Application Publication No. CN 1422327 A discloses a process for upgrading catalytically cracked light cycle oil, comprising the steps of subjecting the light cycle oil produced by the first catalytic cracker using heavy oil as a raw material to deep hydrogenation, and then the hydrogenated light cycle oil is passed to a second catalytic cracker. PRC Patent Application Publication No. CN 1423689 A based on this method further emphasizes that in order to selectively increase the yield of light olefins, the catalyst used in the second catalytic cracking unit must contain from 50 to 95% of the configuration-selective zeolite to about 5 to 50% macroporous zeolite having a pore diameter greater than or equal to approximately 0.7 nm.

PRC Patent Application Publication No. CN 1466619 A discloses a process for converting catalytically cracked light cycle oil in which the catalytic cracking riser reactor is divided into two reaction zones, i.e. the upstream reaction zone and the downstream reaction zone, the heavy oil is sprayed into the downstream reaction zone, the resulting product (catalytic cracking light cycle oil) is hydrogenated to produce a hydrogenated light cycle oil, which is then sprayed into the upstream downstream of the reaction zone. In the method developed from this method and disclosed in PRC Patent Application Publication No. CN 1425054 A, naphtha is introduced into the feedstock in the upstream zone, supplementing the hydrogenated light cycle oil. However, this process consumes a large amount of hydrogen, and the reaction of the hydrogenated light cycle oil in the upstream zone seriously affects the conversion of the heavy oil downstream.

The art still needs a method that can reduce the yield of light cycle oil, increase the yield of catalytically cracked gasoline, and at the same time increase its octane number.

Brief summary of the present invention

In view of the problems of the prior art, the object of the present application is to provide a method and system for producing catalytically cracked gasoline, which allows to increase the yield of high-octane catalytically cracked gasoline by introducing hydrogenated cycle oil and heavy feed oil into the reactor at various points and providing auxiliary catalyst.

In order to solve the above problem, the present application proposes, according to an aspect, a method for producing catalytically cracked gasoline, comprising stages in which:

i) subjecting the heavy feed oil to a catalytic cracking reaction in the presence of a first catalytic cracking catalyst to form a first reaction product;

ii) subjecting the hydrogenated cycle oil to a catalytic cracking reaction in the presence of a second catalytic cracking catalyst to form a second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

wherein step ii) and step i) are carried out in the same riser reactor, and the heavy feed oil and the hydrogenated cycle oil are fed into the riser reactor at different levels thereof, and the first catalytic cracking catalyst and the second catalytic cracking catalyst are introduced into the riser reactor at different levels. points; or

step ii) and step i) are carried out in separate riser reactors and the second reaction product is fed into the upper middle of the riser used in step i) where it is mixed with the first reaction product.

According to some preferred embodiments, the method of the present application comprises the steps of:

i) a heavy feed oil is sprayed into the riser reactor through a first nozzle, a first catalytic cracking catalyst is introduced into the riser reactor at a first injection point located below the first nozzle, and the heavy feed oil is catalytically cracked to form a first reaction product;

ii) the hydrogenated cycle oil is sprayed into the riser used in step i) through the second nozzle, the second catalytic cracking catalyst is introduced into the riser at a second injection point located below the second nozzle, and the hydrogenated cycle oil is subjected to a catalytic cracking reaction to obtain the second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

moreover, the second nozzle and the first nozzle are located at different levels of the riser reactor, and the second point of introduction is different from the first point of introduction.

More preferably, in the height direction of the riser reactor, the second nozzle is positioned above the first nozzle and the second insertion point occupies a position between the first nozzle and the second nozzle.

Even more preferably, the reaction time in the riser section between the first nozzle and the second nozzle is from about 0.05 to about 2 seconds.

Particularly preferably, the following reaction conditions are used in the riser reactor: the reaction temperature is from about 450 to about 650°C, the absolute pressure is from about 0.15 to about 0.4 MPa, the weight ratio of the total weight of the first and second catalytic cracking catalysts and weight the heavy feed oil is from about 1 to about 50, the reaction time of the heavy feed oil is from about 1 to about 10 seconds, and the weight ratio of steam to heavy feed oil is from about 0.01 to about 0.5; the weight ratio of the total weight of the first and second catalytic cracking catalysts to the weight of hydrogenated cycle oil is from about 5 to about 100, the reaction time of hydrogenated cycle oil is from about 1 to about 10 seconds, and the weight ratio of steam to hydrogenated cycle oil is from about 0, 01 to about 0.3, with both the first catalytic cracking catalyst and the second catalytic cracking catalyst having a microactivity of at least about 60.

According to some preferred embodiments, the method of the present application comprises the steps of:

i) the heavy feed oil is sprayed into the primary riser reactor through a first nozzle, the first catalytic cracking catalyst is introduced into the primary riser reactor at a first injection point below the first nozzle, and the heavy feed oil is catalytically cracked to form a first reaction product;

ii) the hydrogenated cycle oil is sprayed into the secondary riser reactor through a second nozzle, the second catalytic cracking catalyst is introduced into the secondary riser reactor at a second injection point located below the second nozzle, and the hydrogenated cycle oil is catalytically cracked to form a second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

moreover, the second reaction product is fed into the upper part of the middle of the primary riser reactor, where it is mixed with the first reaction product.

More preferably, the primary riser reactor comprises a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the outlet of the secondary riser reactor is connected to the second reaction section through a horizontal pipe.

Even more preferably, the following reaction conditions are used in the primary riser reactor: the reaction temperature is from about 450 to about 550° C., the weight ratio of the first catalytic cracking catalyst to the weight of the heavy feed oil is from about 4 to about 8, the reaction time is from about 2 to about 10 seconds, the absolute pressure is from about 0.15 to about 0.4 MPa, the mass ratio of steam to heavy feed oil is from about 0.02 to about 0.08, and the microactivity of the first catalytic cracking catalyst is not less than about 60 ; and/or the following reaction conditions are used in the secondary riser reactor: the reaction temperature is from about 520 to about 650° C., the absolute pressure is from about 0.15 to about 0.4 MPa, the weight ratio of the second catalytic cracking catalyst and hydrogenated cycle oil is from about 5 to about 100, the reaction time is from about 1 to about 10 seconds, the weight ratio of steam to hydrogenated cycle oil is from about 0.01 to about 0.3, and the microactivity of the second catalytic cracking catalyst is not less than about 60 .

According to a preferred embodiment of the process of the present application, the light catalytic cracking cycle oil is separated into a light fraction and a heavy fraction before step iv), the heavy fraction is subjected to hydrogenation in step iv) to obtain a hydrogenated product; and the light end is recycled to step ii) and subjected to a catalytic cracking reaction in the presence of a second catalytic cracking catalyst.

According to a preferred embodiment of the process of the present application, hydrogenation step iv) is carried out to such an extent that the resulting hydrogenated product has a bicyclic aromatic content of no more than about 20 wt. %, a hydrogen content of not less than about 10 wt. %, and the initial boiling point of more than about 165°C.

According to another aspect, the present application provides a catalytic cracking system comprising a primary riser reactor, a secondary riser reactor, a regenerator, a slinger, a main fractionator, a light cycle oil fractionator, and a hydrogenation reactor, wherein:

the primary riser reactor includes a bottom feed inlet, a bottom catalyst inlet, and an top outlet, the secondary riser reactor includes a first feed inlet and a second feed inlet at the bottom, a bottom catalyst inlet and an top outlet, and the top outlet of the secondary riser reactor is connected to the upper part of the middle of the primary riser reactor through a horizontal pipe,

the top outlet of the primary riser reactor is connected to the tappet inlet, the catalyst outlet from the tappet is connected to the regenerator, the oil gas outlet from the tappet is connected to the inlet of the main fractionation column, and the light cycle oil outlet from the main fractionator is connected to the inlet of the light cycle oil fractionation column,

the heavy end outlet from the light cycle oil fractionation column is connected to the hydrogenation reactor inlet, the light end outlet from the light cycle oil fractionation column is connected to the second feed inlet of the secondary riser reactor, and the hydrogenated product outlet from the hydrogenation reactor is connected to the first feed inlet of the secondary riser -reactor, and

the regenerated catalyst outlet from the regenerator is connected to the catalyst inlet of the primary riser reactor and the catalyst inlet of the secondary riser reactor, respectively.

According to a preferred embodiment of the system of the present application, the primary riser reactor comprises a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the upper outlet of the secondary riser reactor is connected to the second reaction section through a horizontal pipe.

Compared to the prior art, the method and system of the present application may provide one or more of the following advantages:

1. complete elimination of the formation of light cycle oil can be achieved;

2. By feeding the heavy feed oil and the hydrogenated cycle oil into the single riser reactor at its various levels and providing an auxiliary catalytic cracking catalyst, the separate processing of the two feed oils becomes possible, which can help optimize the reaction conditions used individually for the two feed oils, and, in turn, lead to their maximum conversion in such a way that the production of high-octane catalytically cracked gasoline can be increased; and by supplying the hydrogenated cycle oil downstream of the relatively heavy feed oil, the reaction time of the hydrogenated cycle oil can be effectively shortened, and thus the yield of high-octane gasoline can be further increased; and

3. By separately processing the heavy feed oil and the hydrogenated cycle oil in the primary and secondary riser reactors, different reaction conditions in the risers can be used so that optimization can be carried out to meet the stringent conditions required for catalytic cracking of the hydrogenated cycle oil; and thus, by directly connecting the outlet of the secondary riser reactor to the upper middle part of the primary riser reactor, the reaction time of the hydrogenated cycle oil can be shortened so that the production of high-octane catalytically cracked gasoline can be increased, equipment can be simplified, and equipment costs can be reduced.

Further, other characteristics and advantages of the present invention will be described in detail in the section "Detailed disclosure of the present invention".

Brief description of the figures

The figures that form part of the present description are presented to aid understanding of the present application and should not be construed as limiting. The present application may be construed with reference to the figures in conjunction with the detailed description provided herein below. Among the figures:

In FIG. 1 is a schematic process diagram of a preferred embodiment according to the present application.

In FIG. 2 is a schematic process diagram of another preferred embodiment according to the present application.

In FIG. 3 is a schematic process diagram of yet another preferred embodiment of the present application.

In FIG. 4 is a schematic process diagram of a further preferred embodiment according to the present application.

Description of the symbols shown in Fig. one

101 - Pipeline for light cycle oil

102 - Hydrogen pipeline

103 - Hydrogenation reactor

104 - Hydrogenated cycle oil pipeline

105 - Heavy feed oil pipeline

106 - Second nozzle

107 - First nozzle

108 - Inclined pipe of the second regenerated catalyst

109 - Spool valve of the second regenerated catalyst

110 - Inclined pipe of the first regenerated catalyst

111 - Spool valve of the first regenerated catalyst

112 - Weeder

113 - Regenerator

114 - Product pipeline

115 - Oil gas pipeline

116 - Recirculation pipeline

117 - Pipeline suspension in oil

118 - Fractionation column

119 - Lift reactor

I - Heavy feed oil reaction zone

II - Hydrogenated Cycle Oil Reaction Zone

Description of the symbols shown in Fig. 2

201 - Heavy fraction pipeline

202 - Hydrogen pipeline

203 - Hydrogenation reactor

204 - Hydrogenated cycle oil pipeline

205 - Heavy base oil pipeline

206 - Second nozzle

207 - Third nozzle

208 - First nozzle

209 - Inclined pipe of the second regenerated catalyst

210 - Spool valve of the second regenerated catalyst

211 - Inclined pipe of the first regenerated catalyst

212 - Spool valve of the first regenerated catalyst

213 - Weeder

214 - Regenerator

215 - Product pipeline

216 - Oil gas pipeline

217 - Main fractionation column

218 - Light cycle oil fractionation column

219 - Light fraction pipeline

220 - Recirculation pipeline

221 - Lift reactor

I - Heavy feed oil reaction zone

II - Hydrogenated Cycle Oil Reaction Zone

Description of the symbols shown in Fig. 3

301 - Primary elevator reactor

302 - Hydrogenation reactor

303 - Fractionation column

304 - Secondary elevator reactor

305 - Regenerator

306 - Weeder

307 - First nozzle

308 - Second nozzle

309 - Inclined pipe of the second regenerated catalyst

310 - Inclined pipe of the first regenerated catalyst

311 - Recirculation pipeline

312 - Pipeline for light cycle oil

313 - Hydrogen pipeline

314 - Oil gas pipeline

315 - Pipeline suspension in oil

316 - Hydrogenated cycle oil pipeline

317 - Product pipeline

I - First reaction section

II - Second reaction section

Description of the symbols shown in Fig. four

401 - Primary elevator reactor

402 - Light cycle oil fractionation column

403 - Main fractionation column

404 - Secondary elevator reactor

405 - Regenerator

406 - Weeder

407 - First nozzle

408 - Second nozzle

409 - Inclined pipe of the second regenerated catalyst

410 - Inclined pipe of the first regenerated catalyst

411 - Pipeline for light cycle oil

412 - Hydrogenated cycle oil pipeline

413 - Heavy fraction pipeline

414 - Oil gas pipeline

415 - Pipeline suspension in oil

416 - Hydrogen pipeline

417 - Product pipeline

418 - Light fraction pipeline

419 - Third nozzle

420 - Hydrogenation reactor

I - First reaction section

II - Second reaction section

Detailed disclosure of the present invention

Further, the present application will be described in detail below in this document with reference to the relevant specific embodiments and accompanying figures. It should be noted that specific embodiments of the present application are presented solely for the purpose of illustration and are not intended to be limiting in any way.

Any specific numerical value, including the end points of the numerical range described in the context of this application, is not limited to the corresponding exact value, but should be construed as further covering all values near the aforementioned exact value. In addition, with respect to any numerical range described herein, arbitrary combinations may be made between the endpoints of the range, between each endpoint and any particular value within the range, or between any two particular values within the range to produce one or more new numerical ranges, and one or more of the above new numerical ranges should also be considered as specifically described in this application.

Unless otherwise stated, terms used herein have meanings that are generally understood by those skilled in the art; and if terms defined herein and their definitions differ from the meanings commonly understood in the art, the definition provided herein shall prevail.

In the context of the present application, in addition to the specifically stated items, any item or items that are not mentioned are considered the same as items known in the art, without any change. In addition, any of the embodiments described herein may be freely combined with one or more of the other embodiments described herein, and the technical solutions or ideas obtained in this way should be considered as part of the original disclosure or original description of this applications, and not as a novel subject that has not been described or contemplated herein, unless those skilled in the art understand that such a combination is manifestly unreasonable.

In the context of the present application, the microactivity test (MAT) of the catalytic cracking catalyst was carried out by the method according to the standard of the Research Institute of Petroleum Refining Corporation (RIPP) 92-90 (see "Petrochemical analysis method (PIPP test method)", editors Cuiding Yang et al., Science Press, September 1990, 1st edition, pages 263-268).

All patent and non-patent documents cited herein, including, without limitation, tutorials and journal articles, are incorporated herein by reference in their entirety.

As described above, in order to solve the existing problems of the prior art, the present application proposes, according to the first aspect, a method for producing catalytically cracked gasoline, comprising the steps in which:

i) subjecting the heavy feed oil to a catalytic cracking reaction in the presence of a first catalytic cracking catalyst to form a first reaction product;

ii) subjecting the hydrogenated cycle oil to a catalytic cracking reaction in the presence of a second catalytic cracking catalyst to form a second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

wherein step ii) and step i) are carried out in the same riser reactor, and the heavy feed oil and the hydrogenated cycle oil are fed into the riser reactor at different levels thereof, and the first catalytic cracking catalyst and the second catalytic cracking catalyst are introduced into the riser reactor at different levels. points; or

step ii) and step i) are carried out in separate riser reactors, and the second reaction product is fed into the upper middle part of the riser used in step i), where it is mixed with the first reaction product.

According to some preferred embodiments, the method of the present application comprises the steps of:

i) a heavy feed oil is sprayed into the riser reactor through a first nozzle, a first catalytic cracking catalyst is introduced into the riser reactor at a first injection point located below the first nozzle, and the heavy feed oil is subjected to a catalytic cracking reaction to form a first reaction product;

ii) the hydrogenated cycle oil is sprayed into the riser used in step i) through the second nozzle, the second catalytic cracking catalyst is introduced into the riser at a second injection point located below the second nozzle, and the hydrogenated cycle oil is subjected to a catalytic cracking reaction to obtain the second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

moreover, the second nozzle and the first nozzle are located at different levels of the riser reactor, and the second point of introduction is different from the first point of introduction.

According to such preferred embodiments, there is no particular requirement for the relative positional relationship between the first nozzle and the second nozzle, and the first nozzle may be positioned above or below the second nozzle. Preferably, in the height direction of the riser reactor, the second nozzle is positioned above the first nozzle and the second insertion point occupies a position between the first nozzle and the second nozzle.

According to such preferred embodiments, the hydrogenated cycle oil and heavy feed oil are fed to the riser reactor at different levels, and thus the catalytic cracking conditions can be optimized to meet the requirements of each feed oil and suitably maximize its conversion. In addition, an auxiliary catalyst is introduced prior to contacting the mixture of resulting petroleum gas and spent catalyst with the hydrogenated cycle oil, which favorably promotes the conversion of the hydrogenated cycle oil.

According to a further preferred embodiment, the reaction time in the riser section between the first nozzle and the second nozzle may range from about 0.05 to 2 seconds, preferably from about 0.1 to 1 second.

According to a particularly preferred embodiment, the following reaction conditions are used in the riser reactor: the reaction temperature is from about 450 to about 650°C, preferably from about 490 to about 550°C, the absolute pressure is from about 0.15 to about 0.4 MPa , the weight ratio of the total weight of the first and second catalytic cracking catalysts to the weight of the heavy feed oil is from about 1 to about 50, preferably from about 3 to about 30, and the reaction time of the heavy feed oil is from about 1 to about 10 seconds, preferably from about 2 to about 8 seconds, and the weight ratio of steam to heavy feed oil is from about 0.01 to about 0.5, preferably from about 0.02 to about 0.2; the weight ratio of the total weight of the first and second catalytic cracking catalysts to the weight of the hydrogenated cycle oil is from about 5 to about 100, preferably from about 8 to about 50, the reaction time of the hydrogenated cycle oil is from about 1 to about 10 seconds, preferably from about 2 to about 8 seconds, and the weight ratio of steam to hydrogenated cycle oil is from about 0.01 to about 0.3, preferably from about 0.01 to about 0.1, with both the first catalytic cracking catalyst and the second catalytic cracking catalyst cracking microactivity is not less than about 60, preferably not less than about 62.

According to some other preferred embodiments, the method of the present application comprises the steps of:

i) the heavy feed oil is sprayed into the primary riser reactor through a first nozzle, the first catalytic cracking catalyst is introduced into the primary riser reactor at a first injection point below the first nozzle, and the heavy feed oil is catalytically cracked to form a first reaction product;

ii) the hydrogenated cycle oil is sprayed into the secondary riser reactor through a second nozzle, the second catalytic cracking catalyst is introduced into the secondary riser reactor at a second injection point located below the second nozzle, and the hydrogenated cycle oil is catalytically cracked to form a second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

moreover, the second reaction product is fed into the upper part of the middle of the primary riser reactor, where it is mixed with the first reaction product.

According to a further preferred embodiment, the following reaction conditions are used in the primary riser reactor: the reaction temperature is from about 450 to about 550° C., preferably from about 500 to about 520° C., the weight ratio of the first catalytic cracking catalyst to the weight of heavy feed oil is from about 4 to about 8, preferably from about 5 to about 7, the reaction time is from about 2 to about 10 seconds, preferably from about 2 to about 8 seconds, the absolute pressure is from about 0.15 to about 0.4 MPa, mass the ratio of steam to heavy feed oil is from about 0.02 to about 0.08, preferably from about 0.03 to about 0.05, and the microactivity of the first catalytic cracking catalyst is not less than about 60, preferably flax not less than about 62; and/or the following reaction conditions are used in the secondary riser reactor: the reaction temperature is from about 520 to about 650°C, preferably from about 550 to about 590°C, the absolute pressure is from about 0.15 to about 0.4 MPa, the weight ratio of the second catalytic cracking catalyst and the hydrogenated cycle oil is from about 5 to about 100, preferably from about 8 to about 50, the reaction time is from about 1 to about 10 seconds, preferably from about 1 to about 8 seconds, the weight ratio of steam and hydrogenated cycle oil is from about 0.01 to about 0.3, preferably from about 0.02 to about 0.2, and the microactivity of the second catalytic cracking catalyst is not less than about 60, preferably not less than about 62.

In a preferred embodiment of the process of the present application, the weight ratio of the first catalytic cracking catalyst to the second catalytic cracking catalyst may be from about 1:0.02 to about 1:1, preferably from about 1:0.03 to about 1:0.5.

According to a preferred embodiment of the process of the present application, the riser reactor may be a constant diameter riser reactor with or without a fluidized bed reactor, or a variable diameter riser reactor with or without a fluidized bed reactor.

According to a further preferred embodiment, the primary riser reactor may comprise a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the outlet of the secondary riser reactor is connected to the second reaction section. through a horizontal pipe.

According to some preferred embodiments of the process of the present application, the light catalytic cracking cycle oil may be separated into a light cut and a heavy cut prior to step iv), the heavy cut is hydrogenated to produce a hydrogenated product in step iv), and the light cut is recycled to step ii), and subjected to a catalytic cracking reaction in the presence of a second catalytic cracking catalyst.

In a further preferred embodiment, catalytically cracked light cycle oil can be separated at a cutoff boiling point of about 240 to about 260°C.

According to some preferred embodiments of the process of the present application, light catalytic cracking cycle oil from an external source, or a fraction thereof, may also be hydrotreated in step iv) and the resulting hydrogenated product may be recycled to step ii) in the form of hydrogenated cycle oil for reaction catalytic cracking, so as to increase the amount of raw materials from the source and produce more high-octane gasoline.

According to the present application, the heavy starting oil used can be any heavy oil well known to those skilled in the art. For example, the heavy feed oil may be selected from the group consisting of virgin paraffinic oil, coker paraffinic oil, deasphalted oil, hydrorefined oil, hydrocracked bottom oil, vacuum distillation residues, atmospheric distillation residues, and combinations thereof. Optionally, other heavy base oils can also be used according to the present application directly or after processing in a manner well known to those skilled in the art.

According to the present application, a variety of catalysts well known to those skilled in the art that are suitable for use in the catalytic cracking of heavy oils can be used as a catalytic cracking catalyst. According to a preferred embodiment, each of the first catalytic cracking catalyst and the second catalytic cracking catalyst independently contains, on a dry matter basis, from about 10% to about 50 wt. % zeolite, from about 5% to about 90 wt. % inorganic oxide, from about 0% to about 70 wt. % clay relative to the weight of the catalytic cracking catalyst; the zeolite is preferably selected from the group consisting of Y zeolite with or without a rare earth element, HY zeolite with or without a rare earth element, USY zeolite with or without a rare earth element, beta zeolite with or without a rare earth element, and their combinations; the inorganic oxide is preferably selected from the group consisting of silicon dioxide, alumina and combinations thereof; and preferably kaolin and/or halloysite is selected as the clay.

According to the present application, hydrogenation step iv) can be carried out under conditions well known to those skilled in the art. For example, step iv) may be carried out in the presence of a hydrogenation catalyst comprising an active metal component and a support, the active metal component may be a Group VIB metal and/or a Group VIII non-noble metal, and the support may be selected from the group consisting of alumina, silicon dioxide, amorphous silicon-aluminum double oxide, and combinations thereof. Preferably the active metal component may be nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum or cobalt-molybdenum. More preferably, the hydrogenation catalyst may contain from about 15% to about 30 wt. % active metal component and from about 70% to about 85 wt. % carrier.

According to a preferred embodiment, the hydrogenation conditions used in hydrogenation step iv) can be defined as follows: hydrogen partial pressure is from about 5.0 to about 22.0 MPa, preferably from about 8.0 to about 15.0 MPa, the reaction temperature is from about 330 to about 450°C, preferably from about 340 to about 380°C, the space velocity is from about 0.1 to about 10.0 h ^-1 , preferably from about 0.1 to about 3.0 h ^-1 and the volume ratio of hydrogen and oil is from about 100 to about 2000 Nm ³ /m ³ preferably from about 350 to about 1200 Nm ³ /m ³ .

According to some preferred embodiments of the method of the present application, the product obtained in step iv) can be separated to obtain a fraction in which the initial boiling point is more than about 165°C, preferably more than about 170°C, or a fraction in which the initial boiling point is greater than about 250°C, preferably greater than about 260°C, and which can be used as the hydrogenated product (which may also be referred to as "hydrogenated light cycle oil" or "hydrogenated heavy cut" depending on the source material used in hydrogenation). Preferably, step iv) is carried out to such an extent that the hydrogenated product has a bicyclic aromatic content of no more than about 20 wt. %, preferably not more than about 10 wt. %, preferably not more than about 8 wt. %, and a hydrogen content of not less than about 10 wt. %, preferably not less than about 11 wt. %, preferably not less than about 14 wt. %.

According to some specific embodiments of the method of the present application, the spent catalyst obtained from the catalytic cracking reaction (including the first spent catalyst obtained from the first catalytic cracking catalyst and the second spent catalyst obtained from the second catalytic cracking catalyst) is regenerated in the regenerator by burning coke to form a regenerated catalyst, which is then returned to steps i) and ii), respectively, as the first catalytic cracking catalyst and the second catalytic cracking catalyst. In this case, the weight ratio of the first catalytic cracking catalyst and the second catalytic cracking catalyst means the cyclic weight ratio of the regenerated catalyst recycled as the first catalytic cracking catalyst and the regenerated catalyst recycled as the second catalytic cracking catalyst.

According to a first type of specific embodiments, the present application proposes a process for producing catalytically cracked gasoline, comprising the steps of:

i) the heavy feed oil is sprayed into the riser reactor through the first nozzle to be brought into contact with the catalytic cracking catalyst and subjected to the catalytic cracking reaction,

ii) the hydrogenated cycle oil is sprayed into the riser reactor through a second catalytic cracking catalyst contact nozzle and subjected to a catalytic cracking reaction;

iii) the catalytic cracking reaction product from the riser is separated to produce catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil, or a fraction thereof, is brought into contact with a hydrogenation catalyst in a hydrogenation reactor and hydrotreated to produce a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

wherein the aforementioned contacting with the catalytic cracking catalyst in steps i) and ii) involves contacting with the first catalytic cracking catalyst introduced into the riser reactor at the first point of introduction located below the first nozzle and the second catalytic cracking catalyst introduced into the riser the reactor at a second injection point located below the second nozzle, wherein the second nozzle is spaced from the first nozzle in the height direction of the riser reactor, and the second injection point is different from the first injection point.

Preferably, in the height direction of the riser reactor, the second nozzle is positioned above the first nozzle, and the second catalytic cracking catalyst is introduced into the riser reactor at a second insertion point positioned between the first nozzle and the second nozzle.

More preferably, the reaction time in the riser section between the first nozzle and the second nozzle may range from about 0.05 to 2 seconds, preferably from about 0.1 to 1 second.

Preferably, the light catalytic cracking cycle oil may be separated into a light cut and a heavy cut prior to step iv), and the heavy cut may be hydrotreated by contacting a hydrogenation catalyst in a hydrogenation reactor in step iv) to produce a hydrogenated product. More preferably, the light fraction may be recycled to step ii), sprayed into the riser through a separate third nozzle, or sprayed into the riser through a second nozzle along with the hydrogenated product, and subjected to a catalytic cracking reaction by being brought into contact with a catalytic cracking catalyst. Particularly preferably, the third nozzle is located below the second nozzle in the height direction of the riser reactor, and more preferably, the second, third and first nozzles occupy the upper, middle and lower relative positions, respectively.

Preferably, the heavy feed oil may be selected from the group consisting of virgin paraffinic oil, coker paraffinic oil, deasphalted oil, hydrorefined oil, hydrocracked bottom oil, vacuum distillation residues, atmospheric distillation residues, and combinations thereof.

According to such embodiments, the catalytic cracking reaction may be carried out under conditions well known to those skilled in the art. For example, for a heavy feed oil, the following catalytic cracking conditions can be determined: reaction temperature (at the outlet of the riser reactor) is from about 450 to about 650°C, preferably from about 490 to about 550°C, the absolute pressure is from about 0, 15 to about 0.4 MPa, the weight ratio of the total weight of the first and second catalytic cracking catalysts and the weight of the heavy feed oil is from about 1 to about 50, preferably from about 3 to about 30, the reaction time (from the first nozzle to the outlet of the riser reactor ) is from about 1 to about 10 seconds, preferably from about 2 to about 8 seconds, the steam to heavy feed weight ratio is from about 0.01 to about 0.5, preferably from about 0.02 to about 0.2. For hydrogenated cycle oil, the following catalytic cracking conditions can be determined: reaction temperature (at the outlet of the riser reactor) is from about 450 to about 650°C, preferably from about 490 to about 550°C, the absolute pressure is from about 0.15 to about 0.4 MPa, the weight ratio of the total weight of the first and second catalytic cracking catalysts and the weight of the hydrogenated cycle oil is from about 5 to about 100, preferably from about 8 to about 50, the reaction time (from the second nozzle to the exit of the riser reactor) is from about 1 to about 10 seconds, preferably from about 2 to about 8 seconds, the weight ratio of steam to hydrogenated cycle oil is from about 0.01 to about 0.3, preferably from about 0.01 to about 0.1, and as at the first cat the catalytic cracking assay and the second catalytic cracking catalyst have a microactivity of at least about 60, preferably at least about 62, as measured by the RIPP 92-90 test used in the catalytic cracking art to determine the microactivity of equilibrium catalysts.

Preferably, each of the first catalytic cracking catalyst and the second catalytic cracking catalyst independently contains, in terms of dry matter, from about 10% to about 50 wt. % zeolite, from about 5% to about 90 wt. % inorganic oxide, from about 0% to about 70 wt. % clay relative to the weight of the catalytic cracking catalyst; the zeolite is selected from the group consisting of Y zeolite with or without a rare earth element, HY zeolite with or without a rare earth element, USY zeolite with or without a rare earth element, beta zeolite with or without a rare earth element, and combinations thereof ; the inorganic oxide is selected from the group consisting of silicon dioxide, alumina, and combinations thereof; and kaolin and/or halloysite is selected as the clay.

Preferably, the riser reactor may be a constant diameter riser reactor with or without a fluidized bed reactor, or a variable diameter riser reactor with or without a fluidized bed reactor.

Preferably, the hydrogenation catalyst may contain an active metal component and a support, the active metal component may be a Group VIB metal and/or a Group VIII non-noble metal, and the support may be selected from the group consisting of alumina, silica, amorphous silica and alumina. and their combinations.

More preferably, the active metal component may be nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum or cobalt-molybdenum.

Even more preferably, the hydrogenation catalyst may contain from about 15% to about 30 wt. % active metal component and from about 70% to about 85 wt. % carrier.

Preferably, hydrogenation step iv) uses the following hydrogenation conditions: hydrogen partial pressure is from about 5.0 to about 22.0 MPa, preferably from about 8.0 to about 15.0 MPa, the reaction temperature is from about 330 to about 450° C, preferably from about 340 to about 380°C, the space velocity is from about 0.1 to about 10.0 h ^-1 , preferably from about 0.1 to about 3.0 h ^-1 , and the volume ratio of hydrogen and

oil is from about 100 to about 2000 Nm ³ /m ³ , preferably from about 350 to about 1200 Nm ³ /m ³ .

Preferably, the product from step iv) may be separated to obtain a fraction having an initial boiling point of greater than about 165°C, preferably greater than about 170°C, or a fraction having an initial boiling point of greater than about 250 °C, preferably greater than about 260 °C, and which may be used as the hydrogenated product (which may also be referred to as "hydrogenated light cycle oil" or "hydrogenated heavy cut" depending on the feedstock used in the hydrogenation). More preferably, step iv) may be carried out to such an extent that the hydrogenated product has a bicyclic aromatic content of no more than about 20 wt. %, preferably not more than about 10 wt. %, preferably not more than about 8 wt. %, and a hydrogen content of not less than about 10 wt. %, preferably not less than about 11 wt. %, preferably not less than about 14 wt. %.

Optionally, an external source of light catalytic cracking cycle oil or a fraction thereof can also be hydrotreated in step iv) and the resulting hydrogenated product can be recycled to step ii) in the form of a hydrogenated cycle oil to carry out the catalytic cracking reaction, so as to increase the amount of raw materials from the source and get more high-octane gasoline.

Preferably, the weight ratio of the first catalytic cracking catalyst to the second catalytic cracking catalyst (i.e., cyclic weight ratio per unit time) is in the range of from about 1:0.02 to about 1:1, preferably from about 1:0.03 to about 1:0.5.

Such embodiments of the present application may provide one or more of the following advantages:

1. complete elimination of the formation of light cycle oil can be achieved;

2. By feeding the heavy feed oil and the hydrogenated cycle oil into the single riser reactor at its various levels and providing an auxiliary catalytic cracking catalyst, the separate processing of the two feed oils becomes possible, which can help optimize the reaction conditions used individually for the two feed oils, and, in turn, lead to their maximum conversion in such a way that the production of high-octane catalytically cracked gasoline can be increased; and

3. By supplying the hydrogenated cycle oil downstream of the relatively heavy feed oil, the reaction time of the hydrogenated cycle oil can be effectively shortened, and thus the yield of high-octane gasoline can be further increased.

Next, the first type of specific embodiments of the method of the present application will be described in detail with reference to the accompanying figures, which are not intended to limit the present invention.

As shown in FIG. 1, in a preferred embodiment of the process of the present application, a heavy feed oil is passed through a heavy feed oil conduit 105 and fed into a riser reactor 119 through a first nozzle 107, a catalytically cracked light cycle oil is sent to the hydrogenation reactor 103 via a light cycle oil conduit 101, and hydrogen is introduced into the hydrogenation reactor 103 through the pipeline 102 hydrogen. The resulting hydrogenated product (i.e. hydrogenated cycle oil) is passed through a hydrogenated cycle oil line 104 and fed into the riser reactor 119 through a second nozzle 106. valve 111 of the first regenerated catalyst introduced into the bottom of the riser reactor 119 at the first introduction point as the first catalytic cracking catalyst, and lifted by the pre-lifting medium. After introducing the heavy feed oil into the reaction zone I, the catalyst is brought into contact with the heavy feed oil supplied through the first nozzle 107 and lifted to carry out the catalytic cracking reaction. The resulting mixture of petroleum gas and catalyst is then introduced into the hydrogenated cycle oil II reaction zone, contacted with the hydrogenated cycle oil fed through the second nozzle 106, and lifted to carry out the catalytic cracking reaction. The other part of the regenerated catalyst from the regenerator 113 is passed through the inclined pipe 108 of the second regenerated catalyst under the control of the slide valve 109 of the second regenerated catalyst, and is introduced into the riser reactor 119 at the second injection point located between the first nozzle 107 and the second nozzle 106, as the second catalyst. catalytic cracking, so as to accelerate the cracking reaction of the hydrogenated cycle oil in the reaction zone II of the hydrogenated cycle oil. In the height direction of the riser reactor 119, the second nozzle 106 and the first nozzle 107, respectively, occupy the upper and lower relative positions. The catalytic cracking reaction product and the spent catalyst are removed from the top of the riser 119 and sent to a slinger 112 to separate the reaction product and the catalyst. The separated spent catalyst is passed to the regenerator 113 for regeneration and then returned. The separated reaction product is sent to fractionation column 118 via product line 114 . The resulting oil slurry is withdrawn from the fractionator 118 via the oil slurry conduit 117 and discharged as a product; the resulting petroleum gas is withdrawn from the fractionation column 118 through the petroleum gas pipeline 115 and passed to a subsequent stabilization absorption system (not illustrated) to produce dry gas, liquefied gas and high-octane gasoline; and the resulting catalytically cracked light cycle oil is withdrawn from the fractionation column 118 through the recycle line 116, is sent to the hydrogenation reactor 103 through the light cycle oil line 101, and then returned.

As shown in FIG. 2, according to a further preferred embodiment of the process of the present application, the heavy feed oil is passed through the heavy feed oil conduit 205 and fed into the riser reactor 221 through the first nozzle 208, the heavy cut of the catalytically cracked light cycle oil is sent to the hydrogenation reactor 203 via the heavy feed conduit 201 fractions, and hydrogen is introduced into the hydrogenation reactor 203 through the pipeline 202 hydrogen. The resulting hydrogenated product (i.e., hydrogenated cycle oil) is passed through the hydrogenated cycle oil line 204 and fed to the riser reactor 221 through the second nozzle 206, and the light cut catalytically cracked light cycle oil is passed through the light cut line 219 and fed into the riser reactor 221 through the third nozzle 207. A portion of the regenerated catalyst from the regenerator 214 is passed through the inclined tube 212 of the first regenerated catalyst under the control of the first regenerated catalyst slide valve 211, is introduced into the lower part of the riser reactor 221 at the first injection point as the first catalytic cracking catalyst and lifted with the pre-lifting medium. After the heavy feed oil is introduced into the reaction zone I, the catalyst is contacted with the heavy feed oil supplied through the first nozzle 208 and lifted to carry out the catalytic cracking reaction. The resulting mixture of petroleum gas and catalyst is then introduced into the hydrogenated cycle oil reaction zone II, contacted with the hydrogenated cycle oil supplied through the second nozzle 206, and a light cut of the catalytically cracked light cycle oil is supplied through the third nozzle 207 and lifted to carry out the reaction. catalytic cracking. The other part of the regenerated catalyst from the regenerator 214 is passed through the inclined tube 209 of the second regenerated catalyst under the control of the slide valve 210 of the second regenerated catalyst and is introduced into the riser reactor 221 at the second injection point located between the first nozzle 208 and the second nozzle 206 as the second catalyst. catalytic cracking, so as to accelerate the cracking reaction of the hydrogenated cycle oil and the light fraction in the reaction zone II of the hydrogenated cycle oil. In the height direction of the riser reactor 221, the second nozzle 206, the third nozzle 207, and the first nozzle 208 respectively occupy the upper, middle, and lower relative positions. The catalytic cracking reaction product and the spent catalyst are removed from the top of the riser 221 and sent to a slinger 213 to separate the reaction product and the catalyst. The separated spent catalyst is passed to the regenerator 214 for regeneration and then returned. The separated reaction product is sent to the main fractionation column 217 via a product line 215 . The resulting oil slurry is withdrawn from the main fractionator 217 via the oil slurry conduit 222 and discharged as a product; the resulting petroleum gas is withdrawn from the main fractionation column 217 through the petroleum gas pipeline 216 and passed to a subsequent absorption stabilization system (not illustrated) to produce dry gas, liquefied gas and high-octane gasoline; and the resulting catalytically cracked light cycle oil is withdrawn from the main fractionator 217 and separated in the light cycle oil fractionator 218 to obtain a light fraction and a heavy fraction. The heavy cut of the catalytically cracked light cycle oil discharged through the recycle line 220 is sent to the hydrogenation reactor 203 through the heavy cut line 201 and then returned. The light cut of the catalytically cracked light cycle oil discharged through the light cut conduit 219 is fed to the riser 221 through the third nozzle 207.

According to a second type of specific embodiments, the present application proposes a process for producing catalytically cracked gasoline, comprising the steps of:

i) a heavy feed oil is sprayed into the primary riser reactor through a first nozzle to be brought into contact with a first catalytic cracking catalyst introduced into the primary riser reactor at a first injection point below the first nozzle and subjected to a catalytic cracking reaction to form a first reaction product ;

ii) hydrogenated cycle oil is sprayed into the secondary riser reactor through a second nozzle to be brought into contact with a second catalytic cracking catalyst introduced into the secondary riser reactor at a second injection point located below the second nozzle, and subjected to a catalytic cracking reaction to obtain a second reaction product ;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil, or a fraction thereof, is brought into contact with a hydrogenation catalyst in a hydrogenation reactor and hydrotreated to produce a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii),

moreover, the second reaction product is sent to the upper part of the middle of the primary riser reactor, where it is mixed with the first reaction product, and the mixture obtained from the upper part of the primary riser reactor is separated in stage iii).

Preferably, the catalytically cracked light cycle oil may be separated into a light cut and a heavy cut prior to step iv) and the heavy cut may be hydrotreated in step iv) by contacting a hydrogenation catalyst in a hydrogenation reactor to produce a hydrogenated product. More preferably, the light ends may be recycled to step ii), sprayed into the secondary riser through a separate third nozzle, or sprayed into the secondary riser through the second nozzle along with the hydrogenated product and catalytically cracked therein. Particularly preferably, the third nozzle is located below the second nozzle in the height direction of the secondary riser reactor.

According to such embodiments, the catalytic cracking reaction may be carried out under conditions well known to those skilled in the art. For example, the following reaction conditions may exist in the primary riser reactor: the reaction temperature is from about 450 to about 550° C., preferably from about 500 to about 520° C., the weight ratio of the first catalytic cracking catalyst to the weight of heavy feed oil is from about 4 up to about 8, preferably from about 5 to about 7, the reaction time is from about 2 to about 10 seconds, preferably from about 2 to about 8 seconds, the absolute pressure is from about 0.15 to about 0.4 MPa, the mass ratio of steam and heavy feed oil is from about 0.02 to about 0.08, preferably from about 0.03 to about 0.05, and the microactivity of the first catalytic cracking catalyst is not less than about 60, preferably not less than about 62 when measured RIPP 92-90 test method used in the field of catalytic cracking to determine the microactivity of equilibrium catalysts. The following reaction conditions may exist in the secondary riser reactor: the reaction temperature is from about 520 to about 650°C, preferably from about 550 to about 590°C, the absolute pressure is from about 0.15 to about 0.4 MPa, the mass ratio the second catalytic cracking catalyst and the hydrogenated cycle oil is from about 5 to about 100, preferably from about 8 to about 50, the reaction time is from about 1 to about 10 seconds, preferably from about 1 to about 8 seconds, the weight ratio of steam and hydrogenated cycle oil gas oil is from about 0.01 to about 0.3, preferably from about 0.02 to about 0.2, and the microactivity of the second catalytic cracking catalyst is not less than about 60, preferably not less than about 62.

Preferably, each of the first catalytic cracking catalyst and the second catalytic cracking catalyst independently contains, in terms of dry matter, from about 10% to about 50 wt. % zeolite, from about 5% to about 90 wt. % inorganic oxide, from about 0% to about 70 wt. % clay relative to the weight of the catalytic cracking catalyst; the zeolite is selected from the group consisting of Y zeolite with or without a rare earth element, HY zeolite with or without a rare earth element, USY zeolite with or without a rare earth element, beta zeolite with or without a rare earth element, and combinations thereof ; the inorganic oxide is selected from the group consisting of silicon dioxide, alumina, and combinations thereof; and kaolin and/or halloysite is selected as the clay.

Preferably, the heavy feed oil may be selected from the group consisting of virgin paraffinic oil, coker paraffinic oil, deasphalted oil, hydrorefined oil, hydrocracked bottom oil, vacuum distillation residues, atmospheric distillation residues, and combinations thereof.

Preferably, each of the primary riser and the secondary riser may independently be a fixed diameter riser with or without a fluidized bed reactor, or a variable diameter riser with or without a fluidized bed.

Preferably, the primary riser reactor may comprise a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the outlet of the secondary riser reactor is connected to the second reaction zone through a horizontal pipe.

According to such embodiments, if the height of the primary riser reactor is indicated as h, the top of the middle of the primary riser reactor generally means the part of the riser reactor at a level of about 1/3 h or higher, preferably from about 1/3 h or higher to approximately 4/5 h or less.

Preferably, the hydrogenation catalyst used in step iv) may contain an active metal component and a carrier, the active metal component may be a Group VIB metal and/or a Group VIII non-noble metal, and the carrier may be selected from the group consisting of alumina, silica , amorphous double oxide of silicon and aluminum and combinations thereof. More preferably, the active metal component may be nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum or cobalt-molybdenum.

Even more preferably, the hydrogenation catalyst may contain from about 15% to about 30 wt. % active metal component and from about 70% to about 85 wt. % carrier.

Preferably, in step iv) the following hydroprocessing conditions are used: hydrogen partial pressure is from about 5.0 to about 22.0 MPa, preferably from about 8.0 to about 15.0 MPa, the reaction temperature is from about 330 to about 450°C , preferably from about 340 to about 380°C, the space velocity is from about 0.1 to about 10.0 h ^-1 , preferably from about 0.1 to about 3.0 h ^-1 , and the volume ratio of hydrogen to oil is from about 100 to about 2000 Nm ³ /m ³ , preferably from about 350 to about 1200 Nm ³ /m ³ .

Preferably, the product from step iv) may be separated to produce a fraction having an initial boiling point of greater than about 165°C, preferably greater than about 170°C, or a fraction having an initial boiling point of greater than about 250°C. C, preferably greater than about 260° C., and which may be used as the hydrogenated product (which may also be referred to as "hydrogenated light cycle oil" or "hydrogenated heavy cut" depending on the feedstock used in the hydrogenation). More preferably, step iv) is carried out to such an extent that the hydrogenated product has a bicyclic aromatic content of no more than about 20 wt. %, preferably not more than about 10 wt. %, preferably not more than about 8 wt. %, and a hydrogen content of not less than about 10 wt. %, preferably not less than about 11 wt. %, preferably not less than about 14 wt. %.

Optionally, an external source of light catalytic cracking cycle oil, or a fraction thereof, may also be hydrotreated in step iv) and the resulting hydrogenated product may be recycled to step ii) in the form of a hydrogenated cycle oil to carry out the catalytic cracking reaction, so as to increase the amount of raw materials from the source and get more high-octane gasoline.

Such embodiments of the present application may provide one or more of the following advantages:

1. complete elimination of the formation of light cycle oil can be achieved; and

2. By separately processing the heavy feed oil and the hydrogenated cycle oil in the primary and secondary risers, different reaction conditions in the risers can be used so that optimization can be carried out to meet the stringent conditions required for catalytic cracking of the hydrogenated cycle oil; and thus, by directly connecting the outlet of the secondary riser reactor to the top middle of the primary riser reactor, the reaction time of the hydrogenated cycle oil can be shortened so that the production of high-octane catalytically cracked gasoline can be increased.

Next, the second type of specific embodiments of the present application will be described in detail below with reference to the accompanying figures, which are not intended to limit the present invention.

As shown in FIG. 3, in a preferred embodiment of the process of the present application, a heavy feed oil is fed into the primary riser reactor 301 through a first nozzle 307, a catalytically cracked light cycle oil is sent to a hydrogenation reactor 302 through a light cycle oil conduit 312, and hydrogen is introduced into the hydrogenation reactor 302 through pipeline 313 hydrogen. The resulting hydrogenated product (i.e., hydrogenated cycle oil) is passed through the hydrogenated cycle oil conduit 316 and fed into the secondary riser reactor 304 through the second nozzle 308. to the bottom of the primary riser reactor 301 at the first injection point as the first catalytic cracking catalyst and lifted with the pre-lifting medium. The catalyst is then brought into contact with the heavy feed oil supplied through the first nozzle 307 and lifted to carry out the catalytic cracking reaction. The other part of the regenerated catalyst from the regenerator 305 is passed through the inclined tube 309 of the second regenerated catalyst, introduced into the bottom of the secondary riser reactor 304 at the second injection point as the second catalytic cracking catalyst, and lifted with the prelift medium. The catalyst is then contacted with hydrogenated cycle oil supplied through the second nozzle 308 and lifted to carry out the catalytic cracking reaction. The resulting reaction stream (containing the second reaction product and spent catalyst) is withdrawn from the top outlet of the secondary riser reactor 304, is directed to the upper middle of the primary riser reactor 301 through a horizontal pipe, and is combined with the stream therein. The catalytic cracking reaction product and the spent catalyst are withdrawn from the top of the primary riser 301 and sent to a slinger 306 to separate the reaction product and the catalyst. The separated spent catalyst is passed to the regenerator 305 for regeneration and then returned. The separated reaction product is sent to fractionator 303 via product line 317. The resulting oil slurry is withdrawn from fractionator 303 via slurry oil line 315 and discharged as product; the resulting petroleum gas is withdrawn from the fractionator 303 through the petroleum gas conduit 314 and passed to a subsequent stabilization absorption system (not illustrated) to produce dry gas, liquefied gas and high-octane gasoline; and the resulting catalytically cracked light cycle oil is withdrawn from the fractionation column 303 through the recycle line 311, is sent to the hydrogenation reactor 302 through the light cycle oil line 312, and then returned.

As shown in FIG. 4, in a further preferred embodiment of the process of the present application, a heavy feed oil is fed into the primary riser reactor 401 through a first nozzle 407, a heavy cut of catalytically cracked light cycle oil is sent to a hydrogenation reactor 420 through a heavy cut conduit 413, and hydrogen is introduced into the reactor. hydrogenation 420 through pipeline 416 hydrogen. The resulting hydrogenated product (i.e., hydrogenated cycle oil) is passed through hydrogenated cycle oil conduit 412 and fed to secondary riser 404 through second nozzle 408, and light cut catalytically cracked cycle oil is passed through conduit 418 light ends and fed into the secondary riser reactor 404 through the third nozzle 419. A portion of the regenerated catalyst from the regenerator 405 is passed through the inclined tube 410 of the first regenerated catalyst, introduced into the bottom of the primary riser reactor 401 at the first injection point as the first catalytic cracking catalyst, and lifted by the medium for pre-lift. The catalyst is then brought into contact with the heavy feed oil supplied through the first nozzle 407 and lifted to carry out the catalytic cracking reaction. The other part of the regenerated catalyst from the regenerator 405 is passed through the inclined tube 409 of the second regenerated catalyst, introduced into the bottom of the secondary riser reactor 404 at the second injection point as the second catalytic cracking catalyst, and lifted with the pre-lift medium. The catalyst is then contacted with hydrogenated cycle oil supplied through the second nozzle 408, and a light cut of the catalytic cracking cycle oil is fed through the third nozzle 419 and lifted to carry out the catalytic cracking reaction. The resulting reaction stream (containing the second reaction product and spent catalyst) is withdrawn from the upper outlet of the secondary riser 404, is directed to the upper middle of the primary riser 401 through a horizontal pipe, and is combined with the stream therein. In the height direction of the secondary riser 404, the second nozzle 408 and the third nozzle 419, respectively, occupy the upper and lower relative positions. The catalytic cracking reaction product and the spent catalyst are removed from the top of the primary riser 401 and sent to a slinger 406 to separate the reaction product and the catalyst. The separated spent catalyst is passed to the regenerator 405 for regeneration and then returned. The separated reaction product is sent to the main fractionation column 403 via a product line 417 . The resulting oil slurry is withdrawn from the main fractionator 403 via the oil slurry conduit 415 and discharged as a product; the resulting petroleum gas is withdrawn from the main fractionation column 403 through the petroleum gas pipeline 414 and passed to a subsequent absorption stabilization system (not illustrated) to produce dry gas, liquefied gas and high-octane gasoline; and the resulting catalytically cracked light cycle oil is withdrawn from the main fractionator 403 and sent to the light cycle oil fractionator 402 via the light cycle oil line 411, where it is separated into a light fraction and a heavy fraction. The heavy cut of the catalytically cracked light cycle oil is sent to the hydrogenation reactor 420 via the heavy cut conduit 413 and then returned. The light cut light cut cycle oil catalytically cracked through the light cut line 418 is fed to the secondary riser reactor 404 through the third nozzle 419.

According to a second aspect, the present application proposes a catalytic cracking system comprising a primary riser reactor, a secondary riser reactor, a regenerator, a bleeder, a fractionation column, and a hydrogenation reactor, wherein:

the primary riser reactor comprises a feedstock bottom inlet, a catalyst bottom inlet, and an upper outlet, the secondary riser reactor comprises a feedstock bottom inlet, a catalyst bottom inlet, and an upper outlet, and the secondary riser reactor's upper outlet is connected to the top of the middle of the primary riser reactor through a horizontal pipe.

the top outlet of the primary riser reactor is connected to the tappet inlet, the catalyst outlet from the tappet is connected to the regenerator, the petroleum gas outlet from the tappet is connected to the fractionation column inlet, the light cycle oil outlet from the fractionator is connected to the hydrogenation reactor inlet, and the hydrogenated product outlet from the hydrogenation reactor connected to the feed inlet of the secondary riser reactor,

the regenerated catalyst outlet from the regenerator is connected to the catalyst inlet of the primary riser reactor and the catalyst inlet of the secondary riser reactor, respectively.

According to a preferred embodiment, the primary riser reactor comprises a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the upper outlet of the secondary riser reactor is connected to the second reaction section. through a horizontal pipe.

Next, the above catalytic cracking system according to the present application will be described in detail below with reference to the accompanying figures, which are not intended to limit the present invention.

As shown in FIG. 3, according to a preferred embodiment, the catalytic cracking system of the present application comprises a primary riser reactor 301, a secondary riser reactor 304, a regenerator 305, a slinger 306, a fractionation column 303, and a hydrogenation reactor 302. The primary riser reactor 301 includes a bottom feed inlet ( ie, the first nozzle 307), a lower catalyst inlet and an upper outlet, and the secondary riser reactor 304 includes a lower feed inlet (ie, the second nozzle 308), a lower catalyst inlet, and an upper outlet. The top outlet of the secondary riser reactor 304 is connected to the top middle of the primary riser reactor 301 via a horizontal pipe. The top outlet of the primary riser reactor 301 is connected to the tapper inlet 306. The catalyst outlet from the tappet 306 is connected to the regenerator 305, and the petroleum gas outlet from the tappet 306 is connected to the fractionation column inlet 303. The light cycle oil outlet from the fractionator 303 is connected to the hydrogenation reactor inlet 302. The hydrogenated product outlet from the hydrogenation reactor 302 is connected to the feed inlet of the secondary riser 304. The catalyst outlet from the regenerator 305 is connected to the catalyst inlet of the primary riser 301 and the catalyst inlet of the secondary riser 304, respectively.

In addition, as shown in FIG. 3, the primary riser reactor 301 comprises a first reaction section I and a second reaction section II which extend coaxially from bottom to top, the second reaction section II having a larger internal diameter than the first reaction section I, and the upper outlet of the secondary riser reactor 304 is connected to the second reaction section II through a horizontal pipe. In addition, the outlet section may be located coaxially above the second reaction section II. The outlet section may have a smaller internal diameter than the second reaction section II and the outlet section is connected to the slinger 306.

According to a third aspect, the present application provides a catalytic cracking system comprising a primary riser reactor, a secondary riser reactor, a regenerator, a bleeder, a main fractionator, a light cycle oil fractionator, and a hydrogenation reactor, wherein:

the primary riser reactor comprises a feedstock bottom inlet, a catalyst bottom inlet, and an upper outlet, the secondary riser reactor comprises a feedstock first inlet and a feedstock second inlet at the bottom, a catalyst bottom inlet and a top outlet, and the secondary riser reactor top outlet is connected to the upper part of the middle of the primary riser reactor through a horizontal pipe,

the top outlet of the primary riser reactor is connected to the tappet inlet, the catalyst outlet from the tappet is connected to the regenerator, the oil gas outlet from the tappet is connected to the inlet of the main fractionation column, and the light cycle oil outlet from the main fractionator is connected to the inlet of the light cycle oil fractionation column,

the heavy end outlet from the light cycle oil fractionation column is connected to the hydrogenation reactor inlet, the light end outlet from the light cycle oil fractionation column is connected to the second feed inlet of the secondary riser reactor, and the hydrogenated product outlet from the hydrogenation reactor is connected to the first feed inlet of the secondary riser -reactor, and

the regenerated catalyst outlet from the regenerator is connected to the catalyst inlet of the primary riser reactor and the catalyst inlet of the secondary riser reactor, respectively.

According to a preferred embodiment, the primary riser reactor comprises a first reaction section and a second reaction section which extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the outlet of the secondary riser reactor is connected to the second reaction section via horizontal pipe.

Next, the above catalytic cracking system according to the present application will be described in detail below with reference to the accompanying figures, which are not intended to limit the present invention.

As shown in FIG. 4, according to a preferred embodiment, the catalytic cracking system of the present application includes a primary riser reactor 401, a secondary riser reactor 404, a regenerator 405, a scatter 406, a main fractionator 403, a light cycle oil fractionator 402, and a hydrogenation reactor 420. Primary riser -reactor 401 includes a bottom feed inlet (ie, first nozzle 407), a bottom catalyst inlet, and an upper outlet. The secondary riser reactor 404 includes a first feed inlet (ie, second nozzle 408) and a second feed inlet (ie, third nozzle 419) at the bottom, a bottom catalyst inlet, and a top outlet. The top outlet of the secondary riser reactor 404 is connected to the top middle of the primary riser reactor 401 through a horizontal pipe, and the top outlet of the primary riser reactor 401 is connected to the inlet of the beater 406. The scatter 406 is connected to the inlet of the main fractionator 403. The outlet of the light cycle oil from the main fractionator 403 is connected to the inlet of the fractionator 402 of the light cycle oil. The heavy cut outlet from the light cycle oil fractionation column 402 is connected to an inlet of the hydrogenation reactor 420, and the light ends outlet from the light cycle oil fractionation column 402 is connected to the second feed inlet of the secondary riser reactor 404. The hydrogenated product outlet from the hydrogenation reactor 420 is connected to the first the secondary riser feed inlet 404. The catalyst outlet from the regenerator 405 is connected to the primary riser reactor catalyst inlet 401 and the secondary riser reactor catalyst inlet 404, respectively.

In addition, as shown in FIG. 4, the primary riser reactor 401 comprises a first reaction section I and a second reaction section II which extend coaxially from bottom to top, the second reaction section II having a larger internal diameter than the first reaction section I, and the upper outlet of the secondary riser reactor 404 is connected to the second reaction section II through a horizontal pipe. In addition, the outlet section may be located coaxially above the second reaction section II. The outlet section may have a smaller internal diameter than the second reaction section II and the outlet section is connected to the slinger 406.

According to some preferred embodiments, the following technical solutions are proposed in this application:

A1. A method for producing high-octane gasoline, comprising the steps in which:

the heavy feed oil is sprayed into the riser through the first nozzle to contact with the first catalytic cracking catalyst from the bottom of the riser and the second catalytic cracking catalyst from the middle of the riser, and subjected to a catalytic cracking reaction to obtain a reaction product and a spent catalyst;

the reaction product is separated to produce at least catalytically cracked gasoline and catalytically cracked light cycle oil;

the spent catalyst is sent to a regenerator for regeneration by burning coke to obtain a regenerated catalyst;

the regenerated catalyst is returned to the riser as the first catalytic cracking catalyst and the second catalytic cracking catalyst;

catalytically cracked light cycle oil is contacted with a hydrogenation catalyst in a hydrogenation reactor and hydrotreated to produce a hydrogenated light cycle oil; and

the hydrogenated light cycle oil is sprayed into the riser reactor through a second nozzle and subjected to a catalytic cracking reaction, the second nozzle being spaced from the first nozzle in the height direction of the riser reactor.

A2. The method of claim A1, wherein, in the height direction, the second nozzle is located above the first nozzle, and the second catalytic cracking catalyst is introduced into the riser at a level above the second nozzle or between the first nozzle and the second nozzle.

A3. The method of claim A1 or A2, wherein the reaction time in the riser section between the first nozzle and the second nozzle is in the range of about 0.05 to about 2 seconds.

A4. The process of claim A1, wherein the heavy feed oil is at least one oil selected from the group consisting of virgin paraffin oil, coker paraffin oil, deasphalted oil, hydrorefined oil, hydrocracking bottom oil, vacuum distillation residues, and residues distillation at atmospheric pressure.

A5. The process of claim A1, wherein the following conditions are used for catalytic cracking of the heavy feedstock: the reaction temperature is from about 520 to about 650° C., the absolute pressure is from about 0.15 to about 0.4 MPa, the mass ratio of the total weight of the first and of the second catalytic cracking catalyst and the weight of the heavy feed oil is from about 1 to about 50, the reaction time is from about 1 to about 10 seconds, the weight ratio of steam to heavy feed oil is from about 0.01 to 0.5, and the microactivity of the regenerated catalyst is not less than about 60 as measured by the RIPP 92-90 test method used in the field of catalytic cracking to determine the microactivity of equilibrium catalysts.

A6. The method according to p. A1, in which the regenerated catalyst contains from about 10% to about 50 wt. % zeolite, about 5% to about 90 wt. % inorganic oxide, up to about 0% to about 70 wt. % clay, and the zeolite is at least one zeolite selected from the group consisting of a Y zeolite with or without a rare earth element, a HY zeolite with or without a rare earth element, a USY zeolite with or without a rare earth element, and zeolite beta, containing or not containing a rare earth element.

A7. The method of claim A1, wherein the riser is a fixed diameter riser with or without a fluidized bed reactor or a variable diameter riser with or without a fluidized bed.

A8. The method of claim A1, wherein the hydrogenation catalyst comprises an active metal component and a support, the active metal component is a Group VIB metal and/or a Group VIII non-noble metal, and the support is at least one compound selected from the group consisting of an oxide aluminum, silicon dioxide, and amorphous double oxide of silicon and aluminum.

A9. The method of claim A8, wherein the active metal component is nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum, or cobalt-molybdenum.

A10. The method of claim A1, wherein the following hydroprocessing conditions are used: hydrogen partial pressure is from about 5.0 to about 22.0 MPa, reaction temperature is from about 330 to about 450° C., space velocity is from about 0.1 to about 10.0 h ^-1 and the volume ratio of hydrogen and oil is from about 100 to about 2000 Nm ³ /m ³ .

A11. The method according to p. A1, in which the hydrogenated light cycle oil has a content of bicyclic aromatic compounds, constituting no more than about 20 wt. %.

A12. The process of claim A1, wherein the following conditions are used for catalytically cracking the hydrogenated light cycle oil: reaction temperature is from about 520 to about 650° C., absolute pressure is from about 0.15 to about 0.4 MPa, mass ratio of total mass of the first and second catalytic cracking catalysts and hydrogenated light cycle oil is from about 5 to about 100, the reaction time is from about 1 to about 10 seconds, and the weight ratio of steam to hydrogenated light cycle oil is from about 0.01 to about 0.3 .

A13. The process of claim A1, wherein the cyclic weight ratio of the first catalytic cracking catalyst to the second catalytic cracking catalyst per unit time is in the range of from about 1:0.02 to about 1:1.

IN 1. The catalytic cracking method using two riser reactors includes the following steps:

the heavy feed oil is sprayed into the bottom of the primary riser through the first nozzle to contact the first catalytic cracking catalyst from the bottom of the primary riser, subjected to a first catalytic cracking reaction to produce a first reaction product and a first spent catalyst, and the resultant the product is withdrawn from the top outlet of the primary riser reactor;

the first reaction product is separated in a product separation unit to produce at least catalytically cracked gasoline and catalytically cracked light cycle oil;

catalytically cracked light cycle oil is contacted with a hydrogenation catalyst in a hydrogenation reactor and hydrotreated to produce a hydrogenated light cycle oil;

hydrogenated light cycle oil is sprayed into the secondary riser reactor through a second nozzle to be contacted with a second catalytic cracking catalyst and subjected to a second catalytic cracking reaction to obtain a second reaction product and a second spent catalyst, with the upper outlet of the secondary riser reactor connected to the upper part of the middle primary lift reactor through a horizontal pipe;

the second reaction product and the second spent catalyst are sent to the upper middle part of the primary riser reactor and removed from the upper outlet of the primary riser reactor together with the first reaction product and the first spent catalyst;

the first spent catalyst and the second spent catalyst are sent to a regeneration regenerator by burning coke to obtain a regenerated catalyst, and the regenerated catalyst is returned to the primary riser reactor and the secondary riser reactor separately as the first catalytic cracking catalyst and the second catalytic cracking catalyst; and

the second reaction product is separated together with the first reaction product in a product separation unit.

B2. The process of claim B1, wherein the heavy feed oil is at least one oil selected from the group consisting of virgin paraffin oil, coker paraffin oil, deasphalted oil, hydrorefined oil, hydrocracking bottom oil, vacuum distillation residues, and residual distillation at atmospheric pressure.

B3. The process of claim B1, wherein the first catalytic cracking reaction uses the following conditions: the temperature is from about 450 to about 550° C., the weight ratio of the first catalytic cracking catalyst to the weight of the heavy feed oil is from about 4 to about 8, the reaction time is from about 2 to about 10 seconds, the pressure is from about 0.15 to about 0.4 MPa, the weight ratio of steam to heavy feed oil is from about 0.02 to about 0.08, and the microactivity of the first catalytic cracking catalyst is not less than than about 60 as measured by the RIPP 92-90 test method used in the field of catalytic cracking to determine the microactivity of equilibrium catalysts.

B4. The method according to p. B1, in which each of the first catalytic cracking catalyst and the second catalytic cracking catalyst independently contains from about 10% to about 50 wt. % zeolite, about 5% to about 90 wt. % inorganic oxide, up to about 0% to about 70 wt. % clay, and the zeolite is at least one zeolite selected from the group consisting of a Y zeolite with or without a rare earth element, a HY zeolite with or without a rare earth element, a USY zeolite with or without a rare earth element, and zeolite beta, containing or not containing a rare earth element.

B5. The method of claim B1, wherein each of the primary riser reactor and the secondary riser reactor is independently a constant diameter riser reactor with or without a fluidized bed reactor, or a variable diameter riser reactor with or without a fluidized bed reactor. fluidized bed.

B6. The method of claim B1, wherein the primary riser reactor comprises a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the outlet of the secondary riser reactor is connected to the second reaction section through a horizontal pipe.

B7. The method of claim B1, wherein the hydrogenation catalyst comprises an active metal component and a support, the active metal component is a Group VIB metal and/or a Group VIII non-noble metal, and the support is at least one material selected from the group consisting of an oxide aluminum, silicon dioxide, and amorphous double oxide of silicon and aluminum.

B8. The method of claim B7 wherein the active metal component is nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum, or cobalt-molybdenum.

B9. The method of claim B1, wherein the following hydroprocessing conditions are used: hydrogen partial pressure is from about 5.0 to about 22.0 MPa, reaction temperature is from about 330 to about 450°C, space velocity is from about 0.1 to about 10.0 h ^-1 and the volume ratio of hydrogen and oil is from about 100 to about 2000 Nm ³ /m ³ .

AT 10 O'CLOCK. The method according to p. B1, in which the hydrogenated light cycle oil has a bicyclic aromatics content of not more than about 20 wt. %.

AT 11. The process of claim B1 wherein the following conditions are used for the second catalytic cracking reaction: the reaction temperature is from about 520 to about 650° C., the pressure is from about 0.15 to about 0.4 MPa, the weight ratio of the second catalytic cracking catalyst and hydrogenated light cycle oil is from about 5 to about 100, the reaction time is from about 1 to about 10 seconds, the weight ratio of steam to hydrogenated light cycle oil is from about 0.01 to about 0.3, and the microactivity of the second catalytic cracking catalyst is no less than about 60.

B12. A dual riser catalytic cracking system comprising a primary riser 301, a hydrogenation reactor 302, a product separation unit (i.e., a fractionator) 303, a secondary riser 304, a regenerator 305, and a slinger 306, wherein:

the primary riser reactor 301 includes a lower feed inlet, a lower catalyst inlet, and an upper outlet, the secondary riser reactor 304 comprises a lower feed inlet, a lower catalyst inlet, and an upper outlet, and the upper outlet of the secondary riser 304 is connected to the top of the middle of the primary elevator reactor 301 through a horizontal pipe;

the top outlet of the primary riser reactor 301 is connected to the tappet inlet 306, the catalyst outlet from the tappet 306 is connected to the regenerator 305, the oil gas outlet from the tappet 306 is connected to the product separation unit inlet 303, the light cycle oil outlet from the product separation unit 303 is connected to the reactor inlet hydrogenation reactor 302, the hydrogenated light cycle oil outlet from the hydrogenation reactor 302 is connected to the feed inlet of the secondary riser reactor 304, the catalyst outlet from the regenerator 305 is connected to the catalyst inlet of the primary riser reactor 301 and the catalyst inlet of the secondary riser reactor 304.

B13. The system of claim B12, wherein the primary riser reactor 301 comprises a first reaction section I and a second reaction section II which extend coaxially from bottom to top, the second reaction section II having a larger internal diameter than the first reaction section I, and an upper outlet of the secondary reactor riser 304 is connected to the second reaction section II through a horizontal pipe.

C1. A method for producing catalytically cracked gasoline, comprising the steps in which:

i) subjecting the heavy feed oil to a catalytic cracking reaction in the presence of a first catalytic cracking catalyst to form a first reaction product;

ii) subjecting the hydrogenated cycle oil to a catalytic cracking reaction in the presence of a second catalytic cracking catalyst to form a second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is returned to step ii),

wherein step ii) and step i) are carried out in the same riser reactor, and the heavy feed oil and the hydrogenated cycle oil are fed into the riser reactor at different levels thereof, and the first catalytic cracking catalyst and the second catalytic cracking catalyst are introduced into the riser reactor at different levels. points; or

step ii) and step i) are carried out in separate riser reactors and the second reaction product is fed into the upper middle of the riser used in step i) where it is mixed with the first reaction product.

C2. The method of claim C1, comprising the steps of:

i) a heavy feed oil is sprayed into the riser reactor through a first nozzle, a first catalytic cracking catalyst is introduced into the riser reactor at a first injection point located below the first nozzle, and the heavy feed oil is catalytically cracked to form a first reaction product;

ii) the hydrogenated cycle oil is sprayed into the riser used in step i) through the second nozzle, the second catalytic cracking catalyst is introduced into the riser at a second injection point located below the second nozzle, and the hydrogenated cycle oil is subjected to a catalytic cracking reaction to obtain the second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is returned to step ii),

moreover, the second nozzle and the first nozzle are located at different levels of the riser reactor, and the second point of introduction is different from the first point of introduction.

C3. The method of claim C1, comprising the steps of:

i) the heavy feed oil is sprayed into the primary riser reactor through a first nozzle, the first catalytic cracking catalyst is introduced into the primary riser reactor at a first injection point below the first nozzle, and the heavy feed oil is catalytically cracked to form a first reaction product;

ii) the hydrogenated cycle oil is sprayed into the secondary riser reactor through a second nozzle, the second catalytic cracking catalyst is introduced into the secondary riser reactor at a second injection point located below the second nozzle, and the hydrogenated cycle oil is catalytically cracked to form a second reaction product;

iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil;

iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and

v) the hydrogenated product in the form of hydrogenated cycle oil is returned to step ii),

moreover, the second reaction product is fed into the upper part of the middle of the primary riser reactor, where it is mixed with the first reaction product.

C4. The method of claim C2, wherein, in the height direction of the riser reactor, the second nozzle is located above the first nozzle and the second insertion point is positioned between the first nozzle and the second nozzle.

C5. The method of claim C4, wherein the reaction time in the riser section between the first nozzle and the second nozzle is from about 0.05 to about 2 seconds, preferably from about 0.1 to about 1 second.

C6. The method according to any one of paragraphs. C2, C4 and C5, in which the following reaction conditions are used in the riser reactor: the reaction temperature is from about 450 to about 650°C, preferably from about 490 to about 550°C, the absolute pressure is from about 0.15 to about 0 .4 MPa, the weight ratio of the total weight of the first and second catalytic cracking catalysts and the weight of the heavy feed oil is from about 1 to about 50, preferably from about 3 to about 30, the reaction time of the heavy feed oil is from about 1 to about 10 seconds, preferably from about 2 to about 8 seconds, and the weight ratio of steam to heavy source oil is from about 0.01 to about 0.5, preferably from about 0.02 to about 0.2; the weight ratio of the total weight of the first and second catalytic cracking catalysts to the weight of the hydrogenated cycle oil is from about 5 to about 100, preferably from about 8 to about 50, the reaction time of the hydrogenated cycle oil is from about 1 to about 10 seconds, preferably from about 2 to about 8 seconds, and the weight ratio of steam to hydrogenated cycle oil is from about 0.01 to about 0.3, preferably from about 0.01 to about 0.1, with both the first catalytic cracking catalyst and the second catalytic cracking catalyst cracking microactivity is not less than about 60, preferably not less than about 62.

C7. The method of claim C3, wherein the primary riser reactor uses the following reaction conditions: reaction temperature is from about 450 to about 550°C, preferably from about 500 to about 520°C, the weight ratio of the first catalytic cracking catalyst and the weight of the heavy initial oil is from about 4 to about 8, preferably from about 5 to about 7, the reaction time is from about 2 to about 10 seconds, preferably from about 2 to about 8 seconds, the absolute pressure is from about 0.15 to about 0.4 MPa, the weight ratio of steam to heavy feed oil is from about 0.02 to about 0.08, preferably from about 0.03 to about 0.05, and the microactivity of the first catalytic cracking catalyst is not less than about 60, preferably not less than approximately 6 2; and/or the following reaction conditions are used in the secondary riser reactor: the reaction temperature is from about 520 to about 650°C, preferably from about 550 to about 590°C, the absolute pressure is from about 0.15 to about 0.4 MPa, the weight ratio of the second catalytic cracking catalyst and the hydrogenated cycle oil is from about 5 to about 100, preferably from about 8 to about 50, the reaction time is from about 1 to about 10 seconds, preferably from about 1 to about 8 seconds, the weight ratio of steam and hydrogenated cycle oil is from about 0.01 to about 0.3, preferably from about 0.02 to about 0.2, and the microactivity of the second catalytic cracking catalyst is not less than about 60, preferably not less than about 62.

C8. The method according to any one of paragraphs. C1-C7, in which the weight ratio of the first catalytic cracking catalyst and the second catalytic cracking catalyst is in the range from about 1:0.02 to about 1:1, preferably from about 1:0.03 to about 1:0.5.

C9. The method according to any one of paragraphs. C1-C8, in which the riser reactor is a constant diameter riser reactor with or without a fluidized bed reactor, or a variable diameter riser reactor with or without a fluidized bed reactor.

C10. The method of claim C3 or C7, wherein the primary riser reactor comprises a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the outlet of the secondary riser reactor is connected to the second reaction section through a horizontal pipe.

C11. The method according to any one of paragraphs. C1-C10, additionally providing that:

light catalytic cracking cycle oil is separated into a light fraction and a heavy fraction before step iv), and the heavy fraction is subjected to hydrogenation in step iv) to obtain a hydrogenated product; and

the light end is returned to step ii) and subjected to a catalytic cracking reaction in the presence of a second catalytic cracking catalyst.

C12. The process of claim C11, wherein the catalytically cracked light cycle oil is separated at a cutoff boiling point of about 240 to about 260°C.

C13. The method according to any one of paragraphs. C1-C12, wherein the heavy feed oil is selected from the group consisting of virgin paraffinic oil, coker paraffinic oil, deasphalted oil, hydrorefined oil, hydrocracked residual oil, vacuum distillation residues, atmospheric distillation residues, and combinations thereof.

C14. The method according to any one of paragraphs. C1-C13, in which each of the first catalytic cracking catalyst and the second catalytic cracking catalyst independently contains, in terms of dry matter, from about 10% to about 50 wt. % zeolite, from about 5% to about 90 wt. % inorganic oxide, from about 0% to about 70 wt. % clay relative to the weight of the catalytic cracking catalyst; the zeolite is selected from the group consisting of Y zeolite with or without a rare earth element, HY zeolite with or without a rare earth element, USY zeolite with or without a rare earth element, beta zeolite with or without a rare earth element, and combinations thereof ; the inorganic oxide is selected from the group consisting of silicon dioxide, alumina, and combinations thereof; and kaolin and/or halloysite is selected as the clay.

C15. The method according to any one of paragraphs. C1-C14, wherein step iv) is carried out in the presence of a hydrogenation catalyst containing an active metal component and a carrier, said active metal component being a Group VIB metal and/or a Group VIII non-noble metal, and the carrier being selected from the group consisting of alumina, silicon dioxide, amorphous double oxide of silicon and aluminum and combinations thereof; preferably, the hydrogenation catalyst contains from about 15% to about 30 wt. % active metal component and from about 70% to about 85 wt. % carrier.

C16. The method of claim C15, wherein the active metal component is nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum, or cobalt-molybdenum.

C17. The method according to any one of paragraphs. C1-C16, in which the following hydrogenation conditions are used in step iv): hydrogen partial pressure is from about 5.0 to about 22.0 MPa, preferably from about 8.0 to about 15.0 MPa, the reaction temperature is from about 330 to about 450°C, preferably from about 340 to about 380°C, the space velocity is from about 0.1 to about 10.0 h ^-1 , preferably from about 0.1 to about 3.0 h ^-1 , and the volume the hydrogen to oil ratio is from about 100 to about 2000 Nm ³ /m ³ , preferably from about 350 to about 1200 Nm ³ /m ³ .

C18. The method according to any one of paragraphs. C1-C17, in which the stage of hydrogenation iv) is carried out to such an extent that the resulting hydrogenated product has a content of bicyclic aromatic compounds of not more than about 20 wt. %, preferably not more than about 10 wt. %, preferably not more than about 8 wt. %, a hydrogen content of not less than about 10 wt. %, preferably not less than about 11 wt. %, preferably not less than about 14 wt. %, and the initial boiling point of more than about 165°C., preferably more than about 170°C.

C19. A catalytic cracking system for carrying out the method according to claim C1, comprising a primary riser reactor, a secondary riser reactor, a regenerator, a scatter, a main fractionation column, a light cycle oil fractionation column, and a hydrogenation reactor, wherein:

the primary riser reactor includes a bottom feed inlet, a bottom catalyst inlet, and an top outlet, the secondary riser reactor includes a first feed inlet and a second feed inlet at the bottom, a bottom catalyst inlet and an top outlet, and the top outlet of the secondary riser reactor is connected to the upper part of the middle of the primary riser reactor through a horizontal pipe,

the top outlet of the primary riser reactor is connected to the tappet inlet, the catalyst outlet from the tappet is connected to the regenerator, the oil gas outlet from the tappet is connected to the inlet of the main fractionation column, and the light cycle oil outlet from the main fractionator is connected to the inlet of the light cycle oil fractionation column,

the heavy end outlet from the light cycle oil fractionation column is connected to the hydrogenation reactor inlet, the light end outlet from the light cycle oil fractionation column is connected to the second feed inlet of the secondary riser reactor, and the hydrogenated product outlet from the hydrogenation reactor is connected to the first feed inlet of the secondary riser -reactor, and

the regenerated catalyst outlet from the regenerator is connected to the catalyst inlet of the primary riser and the catalyst inlet of the secondary riser, respectively.

C20. The system of claim C19, wherein the primary riser reactor comprises a first reaction section and a second reaction section that extend coaxially from bottom to top, wherein the second reaction section has a larger internal diameter than the first reaction section, and the upper outlet of the secondary riser reactor is connected to the second reaction section through a horizontal pipe.

Examples

The present application will be further illustrated with reference to the following examples, but the present application is not limited to them.

Starting materials and reagents

In the following examples and comparative examples, the RN-32V hydrogenation catalyst and the protective agent loaded into the hydrogenation reactor were manufactured by Sinopec Catalyst Branch. The hydrogenation catalyst and protective agent were loaded in a volume ratio of 95:5.

In the following examples and comparative examples, the catalytic cracking catalyst used in the riser under the trade name HAC is manufactured by Sinopec Catalyst Branch, and its physical and chemical properties are shown in Table 1.

In the following examples and comparative examples used heavy source oil was a mixed source material containing 90 wt. % paraffin oil of direct distillation and 10 wt. % vacuum distillation residues, and its properties are presented in table 2.

Parameter Calculation

Light cycle oil recycle rate (LRG) = weight of hydrogenated and regenerated light cycle oil / weight of heavy feed oil.

Hydrogen consumption = amount of fresh hydrogen consumed in the hydrogenation reactor / mass of fresh feedstock fed into the hydrogenation reactor.

Method of measurement

The research octane number (RON) of the produced gasoline was measured by the method according to the National Standard of the People's Republic of China GB/T 5487-2015, and the engine octane number (MON) was measured by the method according to the National Standard of the People's Republic of China GB/T 503-2016.

The microactivity (MAT) of the regenerated catalyst was determined by the method according to the RIPP standard 92-90 (see "Petrochemical analysis method (RIPP test method)", editors Cuiding Yang et al., Science Press, September 1990, 1st edition, pages 263- 268) under the following conditions: catalyst: 5.0 g (20-40 mesh); input oil: 1.56 g; reaction time: 70 seconds; reaction temperature: 460°C; catalyst to oil ratio: 3.2; space velocity: 16 h ^-1 .

Example 1

This example was carried out in accordance with the flow chart shown in FIG. 1. The riser used was a constant diameter riser, and the heavy feed oil and hydrogenated cycle oil were sprayed into the riser through the first nozzle and the second nozzle, respectively. The catalytic cracking reaction conditions are shown in Table 3. The reaction time in the riser section between the second nozzle and the first nozzle was 0.2 seconds.

The following hydroprocessing conditions were present: a hydrogen partial pressure of 8.0 MPa, an average reaction bed temperature of 360° C., a space velocity of 0.5 h ^-1 and a hydrogen to oil volume ratio of 1100 Nm ³ /m ³ . The hydrogenated product (i.e. hydrogenated cycle gas oil) had an initial boiling point of 170°C, a content of bicyclic aromatic compounds of 19 wt. % and a hydrogen content of 11 wt. %.

The distribution of the reaction product, the consumption of hydrogen and the octane number of gasoline obtained in this example are presented in table 4.

Example 2

This example was carried out in accordance with the flow chart shown in FIG. 2, where the light catalytic cracking cycle oil was separated into a light fraction and a heavy fraction at a cutoff boiling point of 250°C, the heavy fraction was subjected to hydrogenation to obtain a hydrogenated product (i.e., a hydrogenated cycle oil), and a heavy feed oil hydrogenated cycle oil and light ends were sprayed into the riser reactor through the first nozzle, the second nozzle and the third nozzle, respectively.

The following conditions were used for the catalytic cracking reaction: reaction temperature 500°C, absolute pressure 0.25 MPa, mass ratio of the total weight of the regenerated catalyst introduced into the riser reactor and the heavy feed oil 6.0, the reaction time of the heavy feed oil 2.8 seconds, weight ratio of steam to heavy feed oil 0.05, weight ratio of total weight of regenerated catalyst to hydrogenated cycle oil 20, weight ratio of steam to hydrogenated cycle oil 0.02, weight ratio of total weight of regenerated catalyst to light fraction 40, weight ratio of steam and a light fraction of 0.05 and a regenerated catalyst microactivity of 65. The reaction time in the riser section between the second nozzle and the first nozzle was 1.4 seconds, and the reaction time in the riser section between the third nozzle and the second nozzle was 0.6 seconds .

The following hydroprocessing conditions were present: a hydrogen partial pressure of 8.0 MPa, an average reaction bed temperature of 360° C., a space velocity of 0.5 h ^-1 and a hydrogen to oil volume ratio of 1100 Nm ³ /m ³ . The hydrogenated product (i.e. hydrogenated cycle oil) had an initial boiling point of 250° C., a bicyclic aromatic content of 20 wt. % and a hydrogen content of 10 wt. %.

The distribution of the reaction product, the consumption of hydrogen and the octane number of gasoline obtained in this example are presented in table 4.

Comparative Example 1

The experiment was carried out as described in Example 1, except that the hydrogenated cycle oil and heavy feed oil were combined and then sprayed into the riser through the first nozzle. The catalytic cracking reaction conditions are shown in Table 3.

The hydroprocessing conditions were the same as in Example 1. The hydrogenated product (i.e. the hydrogenated cycle gas oil) had an initial boiling point of 170° C., a bicyclic aromatics content of 19 wt. % and a hydrogen content of 11 wt. %.

The distribution of reaction products, the consumption of hydrogen and the octane number of gasoline obtained in this comparative example are presented in table 4.

Comparative Example 2

The experiment was carried out as described in Example 1, except that all of the regenerated catalyst returned to the riser was introduced at the first injection point. The catalytic cracking reaction conditions are shown in Table 3.

The hydroprocessing conditions were the same as in Example 1. The hydrogenated product (i.e. the hydrogenated cycle gas oil) had an initial boiling point of 170° C., a bicyclic aromatics content of 19 wt. % and a hydrogen content of 11 wt. %.

The distribution of reaction products, the consumption of hydrogen and the octane number of gasoline obtained in this comparative example are presented in table 4.

As can be seen from the results of Table 4, in comparison with Comparative Example 1, which used the combined feed of hydrogenated cycle oil and heavy feed oil, and Comparative Example 2, in which all of the regenerated catalyst was introduced at the first injection point, Examples 1-2 of the present invention demonstrate higher gasoline yield, improved product distribution and increased gasoline octane.

Compared to example 1, example 2 shows reduced hydrogen consumption, improved product distribution and increased gasoline yield due to catalytically cracked light cycle oil separation.

Example 3

This example was carried out in accordance with the flow chart shown in FIG. 3 and the primary and secondary risers used were constant diameter risers. The heavy feed oil was sprayed into the primary riser reactor through the first nozzle, and the hydrogenated cycle oil was sprayed into the secondary riser reactor through the second nozzle. The catalytic cracking reaction conditions are shown in Table 5.

The following hydroprocessing conditions were present: a hydrogen partial pressure of 8.0 MPa, an average reaction bed temperature of 360° C., a space velocity of 0.5 h ^-1 and a hydrogen to oil volume ratio of 1100 Nm ³ /m ³ . The hydrogenated product (i.e. hydrogenated cycle gas oil) had an initial boiling point of 170°C, a content of bicyclic aromatic compounds of 19 wt. % and a hydrogen content of 11 wt. %.

The distribution of reaction products, the consumption of hydrogen and the octane number of gasoline obtained in this example are presented in table 6.

Example 4

The experiment was carried out as described in example 3, except that the primary riser reactor was a variable diameter riser reactor containing (from bottom to top) a pre-lift section, a reaction section (i.e., the first reaction section I), an elongated section ( ie the second reaction section II) and the outlet section. The following reaction conditions were used in the reaction section: reaction temperature 500° C., absolute pressure 0.25 MPa, regenerated catalyst microactivity 64, catalyst to oil weight ratio 6.1, reaction time 1.2 seconds, and steam to heavy feed oil weight ratio 0 .06; and in the elongated section, the following conditions were used: reaction temperature 490° C. and reaction time 5 seconds.

The reaction conditions in the secondary riser reactor and the hydroprocessing conditions were the same as in Example 3, and the recycle rate of the light cycle oil was 0.15. The hydrogenated product (i.e. hydrogenated cycle gas oil) had an initial boiling point of 170°C, a content of bicyclic aromatic compounds of 19 wt. % and a hydrogen content of 11 wt. %.

The distribution of reaction products, the consumption of hydrogen and the octane number of gasoline obtained in this example are presented in table 6.

Example 5

This example was carried out in accordance with the flow chart shown in FIG. 4 and the primary and secondary risers used were constant diameter risers. The heavy feed oil was sprayed into the primary riser reactor through the first nozzle, and the light catalytic cracking cycle oil was separated into a light fraction and a heavy fraction at a cut-off boiling point of 250°C. The heavy fraction was subjected to hydrogenation to obtain a hydrogenated product (ie hydrogenated cycle oil). The hydrogenated cycle oil and the light end were introduced into the secondary riser reactor through the second nozzle and the third nozzle, respectively.

The following catalytic cracking conditions were used in the secondary riser reactor: reaction temperature 550°C, absolute pressure 0.25 MPa, weight ratio of regenerated catalyst introduced into the secondary riser reactor and hydrogenated cycle oil 8, reaction time of hydrogenated cycle gas oil 2.8 , the mass ratio of steam and hydrogenated cycle oil 0.02, the mass ratio of regenerated catalyst and light fraction 6, the mass ratio of steam and light fraction 0.02 and the microactivity of the regenerated catalyst 64. The reaction time in the riser section between the third nozzle and the second nozzle is 0 ,2.

The reaction conditions in the primary riser reactor and the hydroprocessing conditions were the same as in Example 3, and the cyclic weight ratio of the light cycle oil was 0.2. The hydrogenated product (i.e. hydrogenated cycle oil) had an initial boiling point of 250° C., a bicyclic aromatic content of 20 wt. % and a hydrogen content of 10 wt. %.

The distribution of reaction products, the consumption of hydrogen and the octane number of gasoline obtained in this example are presented in table 6.

Comparative Example 3

The experiment was carried out as described in Example 3, except that only the primary riser was used and the secondary riser was omitted. The hydrogenated product obtained by hydrogenation of the light catalytically cracked cycle oil (ie hydrogenated cycle oil) and the heavy feed oil were combined and sprayed into the primary riser reactor through the first nozzle. Conditions for catalytic cracking in the primary riser reactor are presented in Table 5.

The hydroprocessing conditions were the same as in Example 3. The hydrogenated product (i.e. the hydrogenated cycle gas oil) had an initial boiling point of 170° C., a bicyclic aromatics content of 19 wt. % and a hydrogen content of 11 wt. %.

The distribution of reaction products, the consumption of hydrogen and the octane number of gasoline obtained in this comparative example are presented in table 6.

As can be seen from the results of Table 6, in comparison with Comparative Example 3, where a single riser reactor and a combined feed of hydrogenated cycle oil and heavy feed oil are used, Examples 3-5 of the present invention provide an independent reaction medium for hydrogenated LRG, which is favorable for optimizing the reaction of the hydrogenated LRG, and as a result, an increased yield of gasoline with a higher octane number is obtained.

Compared with Example 3, the use of a variable diameter riser reactor having an elongated section as the primary riser reactor in Example 4 enhances the hydrogen transfer reaction and the isomerization reaction, and thereby increases the octane number of gasoline. Compared to example 3, example 5 demonstrates a reduction in hydrogen consumption and an increase in gasoline yield due to the separation of catalytically cracked light cycle oil.

In the above description, the ideas of the present application are presented with reference to specific embodiments. However, it is understood that various modifications and changes can be made without departing from the scope of the present invention, which is set forth in the appended claims. Accordingly, the description and figures are to be considered in an illustrative and not restrictive sense, and all such modifications and changes are intended to be included within the scope of this application.

In addition, it is understood that a variety of features, which for clarity are described herein in the context of separate embodiments, may also be present in combination in one embodiment. However, a variety of features, which for brevity are described in the context of one embodiment, may also be present separately or in any subcombination.

Claims (35)

1. A method for producing catalytically cracked gasoline, comprising the steps at which: one): i) a heavy feed oil is sprayed into the riser reactor through a first nozzle, a first catalytic cracking catalyst is introduced into the riser reactor at a first injection point located below the first nozzle, and the heavy feed oil is catalytically cracked to form a first reaction product; ii) the hydrogenated cycle oil is sprayed into the riser used in step i) through the second nozzle, the second catalytic cracking catalyst is introduced into the riser at a second injection point located below the second nozzle, and the hydrogenated cycle oil is subjected to a catalytic cracking reaction to obtain the second reaction product; iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil; iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii), moreover, in the height direction of the riser reactor, the second nozzle is located above the first nozzle, and the second insertion point occupies a position between the first nozzle and the second nozzle; or 2): i) the heavy feed oil is sprayed into the primary riser reactor through a first nozzle, the first catalytic cracking catalyst is introduced into the primary riser reactor at a first injection point below the first nozzle, and the heavy feed oil is catalytically cracked to form a first reaction product; ii) the hydrogenated cycle oil is sprayed into the secondary riser reactor through a second nozzle, the second catalytic cracking catalyst is introduced into the secondary riser reactor at a second injection point located below the second nozzle, and the hydrogenated cycle oil is catalytically cracked to form a second reaction product; iii) a mixture of the first reaction product and the second reaction product is separated to obtain catalytically cracked gasoline and catalytically cracked light cycle oil; iv) catalytically cracked light cycle oil or a fraction thereof is subjected to hydrogenation to obtain a hydrogenated product; and v) the hydrogenated product in the form of hydrogenated cycle oil is recycled to step ii), moreover, the second reaction product is fed into the upper part of the middle of the primary riser reactor, where it is mixed with the first reaction product. 2. The method according to p. 1, where in option 1 the reaction time in the section of the riser reactor between the first nozzle and the second nozzle is from 0.05 to 2 seconds. 3. The method according to claim 1 or 2, where in option 1 the following reaction conditions are used in the riser reactor: the reaction temperature is from 450 to 650 ° C, the absolute pressure is from 0.15 to 0.4 MPa, the mass ratio of the total mass the first and second catalytic cracking catalysts and the weight of the heavy feed oil is from 1 to 50, the reaction time of the heavy feed oil is from 1 to 10 seconds, and the mass ratio of steam to heavy feed oil is from 0.01 to 0.5; the mass ratio of the total mass of the first and second catalytic cracking catalysts and the mass of the hydrogenated cycle oil is from 5 to 100, the reaction time of the hydrogenated cycle gas oil is from 1 to 10 seconds, and the mass ratio of steam and hydrogenated cycle oil is from 0.01 to 0.3 , wherein both the first catalytic cracking catalyst and the second catalytic cracking catalyst have a microactivity of at least 60. 4. The method according to claim 1, where in option 2 the following reaction conditions are used in the primary riser reactor: the reaction temperature is from 450 to 550 ° C, the mass ratio of the first catalytic cracking catalyst and the mass of heavy initial oil is from 4 to 8, the duration the reaction time is 2 to 10 seconds, the absolute pressure is 0.15 to 0.4 MPa, the weight ratio of steam to heavy feed oil is 0.02 to 0.08, and the microactivity of the first catalytic cracking catalyst is not less than 60; and/or the following reaction conditions are used in the secondary riser reactor: the reaction temperature is from 520 to 650°C, the absolute pressure is from 0.15 to 0.4 MPa, the mass ratio of the second catalytic cracking catalyst and hydrogenated cycle oil is from 5 to 100, the reaction time is 1 to 10 seconds, the mass ratio of steam to hydrogenated cycle oil is 0.01 to 0.3, and the microactivity of the second catalytic cracking catalyst is not less than 60. 5. The method according to any one of paragraphs. 1-4, wherein the weight ratio of the first catalytic cracking catalyst and the second catalytic cracking catalyst is in the range of 1:0.02 to 1:1. 6. The method according to any one of paragraphs. 1-5, wherein the riser is a fixed diameter riser with or without a fluidized bed reactor, or a variable diameter riser with or without a fluidized bed. 7. The method according to claim 1 or 4, where in option 2 the primary riser reactor contains the first reaction section and the second reaction section, which coaxially extend from the bottom up, and the second reaction section has a larger internal diameter than the first reaction section, and the release of the secondary the riser reactor is connected to the second reaction section through a horizontal pipe. 8. The method according to any one of paragraphs. 1-7, further providing that the light catalytic cracking cycle oil is separated into a light cut and a heavy cut before step iv), and the heavy cut is subjected to hydrogenation in step iv) to obtain a hydrogenated product; and the light end is returned to step ii) and subjected to a catalytic cracking reaction in the presence of a second catalytic cracking catalyst. 9. The process of claim 8, wherein the catalytically cracked light cycle oil is separated at a cutoff boiling point of 240 to 260°C. 10. The method according to any one of paragraphs. 1-9, wherein the heavy feed oil is selected from the group consisting of virgin paraffinic oil, coker paraffinic oil, deasphalted oil, hydrorefined oil, hydrocracked bottom oil, vacuum distillation residues, atmospheric distillation residues, and combinations thereof. 11. The method according to any one of paragraphs. 1-10, in which each of the first catalytic cracking catalyst and the second catalytic cracking catalyst independently contains, in terms of dry matter, from 10 to 50 wt.% zeolite, from 5 to 90 wt.% inorganic oxide, from 0 to 70 wt. .% clay relative to the weight of the catalytic cracking catalyst; the zeolite is selected from the group consisting of Y zeolite with or without a rare earth element, HY zeolite with or without a rare earth element, USY zeolite with or without a rare earth element, beta zeolite with or without a rare earth element, and combinations thereof ; the inorganic oxide is selected from the group consisting of silicon dioxide, alumina, and combinations thereof; and kaolin and/or halloysite is selected as the clay. 12. The method according to any one of paragraphs. 1-11, in which step iv) is carried out in the presence of a hydrogenation catalyst containing from 15 to 30 wt.% of the active metal component and from 70 to 85 wt.% of the carrier, the aforementioned active metal component is a Group VIB metal and/or a base metal group VIII, and the carrier is selected from the group consisting of alumina, silicon dioxide, amorphous double oxide of silicon and alumina, and combinations thereof. 13. The method of claim 12 wherein the active metal component is nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum, or cobalt-molybdenum. 14. The method according to any one of paragraphs. 1-13, in which the following hydrogenation conditions are used in step iv): hydrogen partial pressure is 5.0 to 22.0 MPa, reaction temperature is 330 to 450° C., space velocity is 0.1 to 10.0 h ^-1 and the volume ratio of hydrogen and oil is from 100 to 2000 Nm ³ /m ³ . 15. A catalytic cracking system for carrying out the method according to claim 1, comprising a primary riser reactor, a secondary riser reactor, a regenerator, a scatterer, a main fractionation column, a light cycle oil fractionation column, and a hydrogenation reactor, wherein: the primary riser reactor includes a bottom feed inlet, a bottom catalyst inlet, and an top outlet, the secondary riser reactor includes a first feed inlet and a second feed inlet at the bottom, a bottom catalyst inlet and an top outlet, and the top outlet of the secondary riser reactor is connected to the upper part of the middle of the primary riser reactor through a horizontal pipe, the top outlet of the primary riser reactor is connected to the tappet inlet, the catalyst outlet from the tappet is connected to the regenerator, the oil gas outlet from the tappet is connected to the inlet of the main fractionation column, and the light cycle oil outlet from the main fractionator is connected to the inlet of the light cycle oil fractionation column, the heavy end outlet from the light cycle oil fractionation column is connected to the hydrogenation reactor inlet, the light end outlet from the light cycle oil fractionation column is connected to the second feed inlet of the secondary riser reactor, and the hydrogenated product outlet from the hydrogenation reactor is connected to the first feed inlet of the secondary riser -reactor, and the regenerated catalyst outlet from the regenerator is connected to the catalyst inlet of the primary riser reactor and the catalyst inlet of the secondary riser reactor, respectively. 16. The system of claim. 15, in which the primary riser reactor contains a first reaction section and a second reaction section, which coaxially extend from the bottom up, and the second reaction section has a larger internal diameter than the first reaction section, and the upper outlet of the secondary riser reactor connected to the second reaction section through a horizontal pipe.

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