CN111807919B

CN111807919B - Method and device for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon

Info

Publication number: CN111807919B
Application number: CN202010658196.9A
Authority: CN
Inventors: 石宝珍; 李荻; 郭江伟
Original assignee: Qingdao Jingrun Petrochemical Design & Research Institute Co ltd
Current assignee: Qingdao Jingrun Petrochemical Design & Research Institute Co ltd
Priority date: 2020-07-09
Filing date: 2020-07-09
Publication date: 2023-04-25
Anticipated expiration: 2040-07-09
Also published as: CN111807919A

Abstract

The invention relates to a method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon, belonging to the technical field of catalytic conversion of petroleum hydrocarbon. The method is characterized in that a reactor (R10) is arranged into a lower catalytic cracking lower reaction zone (R17) and an upper catalytic cracking upper reaction zone (R18) under mild conditions, heavy petroleum hydrocarbon (R12) sequentially reacts in the lower catalytic cracking lower reaction zone (R17) and the upper catalytic cracking reaction zone (R18) under high temperature, and a catalyst of a regenerator (G10) respectively enters the lower catalytic cracking reaction zone (R17) and the upper catalytic cracking reaction zone (R18) to realize the fractional conversion of macromolecules to ethylene propylene in a reaction process in a fractional control mode. The invention also provides a device for realizing the method.

Description

Method and device for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon

Technical Field

The invention belongs to the technical field of catalytic conversion of petroleum hydrocarbon, in particular to a method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon.

Background

The low-carbon olefin represented by ethylene and propylene is the most basic raw material in the chemical industry, and the existing catalytic conversion technology is by-product low-carbon olefin when producing gasoline and diesel oil, and can not meet the demands of the current market on organic chemical raw materials. Natural gas or light petroleum fraction is used as raw material at home and abroad, and the steam cracking process in the ethylene combined device is adopted to produce low-carbon olefin. Although steam cracking technology has been developed for decades, the technology is perfect, but still has high energy consumption, high production cost and CO ₂ The traditional technology for producing ethylene and propylene by steam cracking is facing serious test due to technical limitations such as large discharge amount, difficult regulation of product structure and the like. The method for preparing ethylene by utilizing the catalytic conversion method, and simultaneously byproducts of chemical raw materials such as propylene, butene and the like, which are novel directions for producing chemical products with low cost and shortage of resources, become important research subjects and hot spot problems at present.

In the aspect of preparing low-carbon olefins such as ethylene, propylene, butylene and the like by catalytic conversion, the following main ideas are provided:

1. the reaction raw materials are divided into light and heavy fractions through a distillation tower, and catalytic reactions are carried out in different reactors respectively. For example, CN109575982A provides a method for preparing low-carbon olefin and aromatic hydrocarbon by catalytic cracking of crude oil, the crude oil is desalted and dehydrated, then is heated in a heating furnace, and then is fed into a distillation tower to separate the crude oil into light and heavy components, and the cutting point is between 150 and 300 ℃; the light component from the top of the tower and the heavy component from the bottom of the tower are in contact reaction with the high-temperature catalyst in two reactors under the water vapor atmosphere.

2. The reactor is internally provided with layered feeding reaction. As in CN1898362 there is provided a process for producing lower olefins and aromatics by contacting the feedstock with a catalytic cracking catalyst, reacting in at least two feeds according to the nature of the feedstock, and returning different liquid reaction products from the fractionating column, except for the desired product, from different locations to the reactor for reconversion. CN1215041a provides a method for preparing ethylene, propylene, aromatic hydrocarbon, etc. by directly converting multiple feed hydrocarbons, wherein multiple groups of feed inlets are arranged on the reactor, so that hydrocarbons with different properties enter the device from different feed inlets, and cracking reaction is performed under the same technological conditions in each part. CN104560154a provides a hydrocarbon catalytic conversion process for the production of higher lower olefins and lighter aromatics, comprising: contacting heavy hydrocarbon raw materials with a cracking catalyst in a first reactor to carry out catalytic cracking reaction, and then separating to obtain a first carbon deposition catalyst and a first reaction product; injecting light hydrocarbon raw materials from the upstream of the second reactor, injecting medium hydrocarbon raw materials from the middle of the second reactor, and carrying out catalytic cracking reaction; and introducing the reaction mixture generated in the second reactor into a third reactor to continue the reaction, and separating to obtain a second carbon deposition catalyst and a second reaction product. Wherein the cracking catalyst is a cracking catalyst containing modified beta zeolite, and the modified beta zeolite is beta zeolite modified by tourmaline and transition metal M.

3. Outside the raw oil lifting pipe, a reactor is additionally built to make different fractions catalytically converted again, namely, a multi-reactor form is adopted, the first reactor carries out the conventional raw oil reaction, and one or more fractions such as crude gasoline enter the reactor to be further converted after fractionation to obtain a target product; for example, CN1388216 discloses a catalytic conversion method for preparing propylene, butene and gasoline with low olefin content, which comprises the following steps: (1) Injecting preheated hydrocarbon oil (still liquid) into a riser, contacting and reacting with a catalyst containing pentasil zeolite and Y-type zeolite, and allowing an oil mixture to enter a fluidized bed through the riser; (2) Gasoline is injected into the fluidized bed, contacted and reacted with catalyst from the riser; (3) Separating the oil mixture, and feeding the reacted catalyst into a regenerator for regeneration after steam stripping, wherein the regenerated catalyst returns to the riser for recycling. The method can increase the yield of low-carbon olefin and can also produce high-quality gasoline with low olefin content. CN1258580C discloses a method and system for modifying catalytic gasoline by deep reduction of olefins and octane number, which is to add a catalytic modifying reactor in the reaction-regeneration system of heavy oil catalytic conversion device to make catalytic modifying reaction on catalytic converted gasoline fraction. The upgraded catalytic conversion gasoline fraction may be a whole crude gasoline fraction, a light crude gasoline fraction or a heavy crude gasoline fraction, which are obtained by establishing a secondary condensing system at the top of a fractionating tower.

4. The light raw material produces low-carbon olefin. CN104557378A discloses a method for producing propylene by catalytic pyrolysis of naphtha. The method comprises the following steps: (1) Under the pretreatment condition, naphtha is contacted with a pretreatment agent to obtain treated oil with reduced basic nitrogen content; (2) And (3) under the condition of naphtha catalytic cracking reaction, the treated oil and water obtained in the step (1) are contacted with a catalyst to obtain a catalytic cracking product.

5. To increase the yield of light olefins, the addition of "co-catalyst" suitable for cracking small molecule hydrocarbons, typically 5-8% of the heavy oil reaction catalyst, can be used, with an increase of 1-1.5% of propylene.

The above Fluid Catalytic Conversion (FCC) olefin reduction techniques and enhanced chemical feedstock techniques share some common drawbacks as follows:

1. different raw materials require different catalysts, and heavy oil pyrolysis requires high macromolecule pyrolysis capability of the catalysts, and generally requires larger pore diameters; the C4 and C5 cracking requires a catalyst with low carbon olefin selectivity, and generally requires smaller pore diameter; the prior art uses the same catalyst, i.e. only one catalyst. Although 5-8% of the auxiliary agent can be added into the regenerator to further convert small molecules in order to increase the yield of the low-carbon olefin, the auxiliary agent, when added into the FCC catalyst, inevitably leads to the reduction of the cracking activity of the catalyst due to the dilution effect of the auxiliary agent on the catalyst. Typically, every 5% of the auxiliary agent is added, the cracking conversion rate of the heavy oil is reduced by 1 percentage point, and the reduction of the conversion rate of the heavy oil is an important factor which seriously affects the technical economy of FCC, and the improvement of the target product is limited due to the low concentration of the auxiliary agent after the auxiliary agent is mixed with the heavy oil cracking catalyst.

2. Because the second reaction system needs more reaction heat, the generated coke is generally less, and the regeneration heat release of the generated coke can not provide the heat needed by the reaction, if the prior art is used for establishing an independent second reaction system, the independent second reaction system is limited by the heat balance problem.

3. The various recycling methods are to separate the fractions by a fractionating tower, cool the fractions into liquid by heat exchange, and then return the liquid to the reactor, wherein different fractions are firstly cooled into liquid by heat exchange of the fractionating tower, and the separated fractions are returned to the original reactor or are further converted by the original reactor after being directly or properly re-preheated (still being liquid). The process of cooling and heating firstly increases equipment and energy consumption investment, so that the economical efficiency of the process technology is greatly reduced.

4. The reaction temperature for preparing olefin from petroleum hydrocarbon is higher and is generally higher than 650 ℃; the reaction process of preparing olefin by catalyzing and cracking raw oil, especially heavy raw oil, is a process of gradually cracking and gradually reducing the molecular weight; the small molecules are difficult to activate, the higher the required reaction temperature is, the natural reheating cracking reaction is at high temperature, and the selectivity of the target product is affected; how to distribute the reaction temperature and the molecular characteristics of petroleum hydrocarbon, balance the catalytic cracking reaction and the thermal cracking reaction, and realize the limit control of the reaction; the desirable reaction process is that the specific gravity of the catalytic reaction is increased as much as possible in the macromolecule cracking stage of heavy oil and the like, the thermal cracking is limited, the temperature is gradually increased in the lower molecule cracking stage, and the thermal cracking reaction proportion is increased; however, the heat in the reaction process of the prior art is provided in the inlet area of the reactor, the reaction is gradually cooled, especially for ethylene production, and the reaction temperature is higher in the initial stage, namely the heavy oil cracking stage at the lower part of the reactor, because of the high reaction temperature, the heavy components directly perform the thermal cracking reaction, and the effect of the catalytic cracking reaction is reduced.

Disclosure of Invention

The invention aims to provide a method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon, which can realize high-yield preparation of various low-carbon olefin products such as ethylene, propylene and the like, has low equipment investment and low energy consumption, and can be used for treating heavy petroleum hydrocarbon or simultaneously treating heavy petroleum hydrocarbon and light hydrocarbon raw materials to produce olefin products. The invention also provides a device for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon.

The invention adopts the following technical scheme:

a method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon comprises the following reaction processes: the heavy oil macromolecules are firstly subjected to catalytic cracking conversion under a mild condition to form intermediate molecules mainly containing C5-C12, and then are subjected to catalytic cracking and thermal cracking combined conversion under a high-severity condition to produce ethylene and propylene; the heavy oil catalytic cracking and cracking conversion of the method are carried out in a reactor, the reactor is provided with heat supply and catalyst circulation in two stages up and down, the reactor is divided into an upper reaction zone and a lower reaction zone, namely a catalytic cracking lower reaction zone and a catalytic cracking upper reaction zone by an upper regenerant (namely an upper catalyst) and a heat supply position (namely an upper regenerant inlet below), the catalytic cracking lower reaction zone or a high-boiling heavy petroleum hydrocarbon low-temperature catalytic cracking reaction zone or a low-temperature reaction zone below the reactor is used for carrying out the conversion catalytic cracking reaction of heavy component macromolecules into C5-C12 intermediate components and providing intermediate raw materials for preparing ethylene and propylene; the upper part of the reactor is a catalytic cracking upper reaction zone, or a reaction zone for preparing olefin by high-temperature cracking or a high-temperature reaction zone, a catalyst (i.e. an upper regenerant) entering from an inlet point above the reactor provides heat to further increase the reaction temperature of the catalytic cracking upper reaction zone, so that the high-temperature reaction zone is formed, and the intermediate components mainly comprising C5-C12 are subjected to catalytic cracking and thermal cracking combined reaction under the harsher conditions of higher temperature and larger catalyst-oil ratio, so that the petroleum hydrocarbon raw material is converted into ethylene and propylene; realizing the selective reaction of high boiling point heavy petroleum hydrocarbon in two-stage heat supply and two-stage catalyst supply reactors in an upper region and a lower region, adapting to the molecular structure of gradually decreasing the molecular weight of the reactant and the change of the requirements on the reaction conditions by using a reaction mode of gradually increasing the reaction temperature, and improving the efficiency of olefin production and the selectivity of target products;

The heavy petroleum hydrocarbon sequentially enters a lower-temperature catalytic cracking lower reaction zone and a high-temperature catalytic cracking upper reaction zone, the low-temperature catalytic cracking reaction and the high-temperature olefin cracking reaction are sequentially realized, the catalyst of the regenerator respectively enters the lower-temperature catalytic cracking reaction zone and the upper-temperature catalytic cracking reaction zone, and the gradual temperature rise of the reaction process is realized by a graded heat supply mode; heavy petroleum hydrocarbon is subjected to catalytic cracking reaction of high boiling point heavy components in a low-temperature reaction zone, catalytic cracking conversion and decarburization and demetallization of the heavy components and macromolecules are finished initially, intermediate components mainly comprising high-olefin gasoline and diesel components are generated, the intermediate products and a catalyst enter the high-temperature reaction zone above a reactor upwards, heat and the catalyst are continuously provided for the zone through another path of catalyst from a regenerator, the temperature and the catalyst-oil ratio of the reactants are improved, and the catalytic cracking reaction of the heavy components and the cracking conversion of the intermediate components and micromolecules are realized; the reaction process comprises the following steps:

(1) The heavy petroleum hydrocarbon is atomized by steam and then is subjected to catalytic cracking reaction in a catalytic cracking lower reaction zone at the lower part of the reactor under the environment of a lower regenerant introduced from a regenerator through a lower regeneration vertical pipe; the reaction zone under catalytic cracking, namely a low-temperature reaction zone, is carried out according to the condition which is favorable for the catalytic conversion of high-boiling-point heavy components, the reaction temperature is 525-620 ℃, and the reaction time is 0.5-5.0 s; the actual reaction temperature and the catalyst-to-oil ratio are controlled by the amount of catalyst entering the low-temperature reaction zone from the lower regeneration vertical pipe;

(2) After the heavy petroleum hydrocarbon completes the low-temperature catalytic cracking reaction, the product and the catalyst generated in the catalytic cracking lower reaction zone flow upwards to enter the catalytic cracking upper reaction zone, and the upper regenerant introduced from the regenerator through the upper regeneration vertical pipe enters the catalytic cracking upper reaction zone to provide heat for the catalytic cracking upper reaction zone, so that the temperature and the catalyst-oil ratio are increased, and the catalytic cracking and thermal cracking combined reaction is continuously carried out to generate an olefin product; the reaction temperature of the catalytic cracking upper reaction zone is 550-750 ℃, the reaction time is 0.1-5.0 s, the absolute pressure of the reaction pressure is 0.20-0.40 MPa, and the actual reaction temperature and the catalyst-oil ratio are controlled by the catalyst amount entering the catalytic cracking upper reaction zone from the upper regeneration vertical pipe;

(3) And (3) feeding the reacted material flow into a settler for gas-solid separation to obtain a reaction product, and feeding the separated catalyst into a regenerator for regeneration after steam stripping in a steam stripping section for recycling.

The method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon further comprises the step of preparing the heavy petroleum hydrocarbon from one or a mixture of vacuum wax oil, (normal pressure) residual oil, coker wax oil, deasphalted oil, hydrogenated wax oil (hydrotreated wax oil), hydrogenated residual oil (hydrotreated residual oil) and crude oil; the boiling point is higher than 320 ℃.

The method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon, further, the petroleum hydrocarbon raw material also comprises independent light hydrocarbon;

when the petroleum hydrocarbon raw material has independent light hydrocarbon raw material which needs to be processed in the reactor, the light hydrocarbon directly or after being heated enters the reactor for catalytic conversion to prepare olefin, or the light hydrocarbon enters a second reactor which is arranged in addition, the second reactor and the reactor share a settler and a regenerator, and a material flow formed by the light hydrocarbon in the second reactor R20 enters the settler.

Preferably, the light hydrocarbon is one or a mixture of naphtha, C4, C5 and hydrocatalytic (cracked) diesel components, the boiling point is lower than 360 ℃, or the light hydrocarbon is hydrocracked tail oil.

Preferably, when the light hydrocarbons are reacted in the reactor, the light hydrocarbons are reacted in the catalytic cracking upper reaction zone, i.e., the light hydrocarbons are directly fed into the high temperature reaction zone of the reactor, and are subjected to catalytic cracking reaction with the reaction product stream from the low temperature reaction zone, and are converted into ethylene and propylene under high severity conditions.

Preferably, when the light hydrocarbon is reacted in the second reactor, heavy oil or recycle oil is supplemented downstream of the second reactor for increasing coke making and oil gas cooling.

In the present invention, preferably, an upper and a lower regeneration zone, i.e., a lower regeneration zone and an upper regeneration zone, are provided below the regenerator dilute phase zone of the regenerator, and a regenerant is provided to the reactor through the upper regeneration zone.

In the invention, preferably, an upper regeneration zone and a lower regeneration zone, namely a lower regeneration zone and an upper regeneration zone are arranged below a dilute phase zone of a regenerator, the upper regeneration zone is a dense phase fluidized bed regeneration zone, and the carbon content and the temperature of the catalysts in the two regeneration zones are regulated by adjusting the distribution of the catalyst amount and the regenerated oxygen amount or the air amount of the lower regeneration zone and the upper regeneration zone; the spent catalyst from the stripping section enters an upper regeneration zone, the catalyst, namely, a lower regenerant is provided for the catalytic cracking lower reaction zone through a lower regeneration zone, and the catalyst, namely, an upper regenerant is provided for the catalytic cracking upper reaction zone through an upper regeneration zone (fluidized bed regeneration zone). In the specific implementation, the carbon content and the temperature of the two regeneration zone catalysts are regulated by regulating the distribution of the catalyst amount and the regenerated oxygen amount or the air amount of the two regeneration zones of the regenerator, so that the heat supply to the high-temperature reaction zone and the supply of the catalysts with different carbon contents to the two reaction zones are realized; when catalysts with different carbon contents are provided for the reactor, the catalyst with high carbon content is provided for the pyrolysis reaction zone at the upper part.

The method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon further comprises the step of preparing a catalyst with carbon content lower than 0.10% at 660-750 ℃ by using a lower regenerant; the temperature of the upper regenerant is 700-780 ℃, and the carbon content of the catalyst is lower than 0.5%.

The method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon is further characterized in that heavy oil or recycle oil is supplemented at the downstream of the reaction zone or/and the stripping zone on the catalytic cracking, so as to increase the heat supplement of raw coke and the temperature reduction of oil gas.

In the present invention, different regeneration modes are needed according to the different requirements of the reaction on the catalyst temperature and the carbon content during the implementation. When the catalyst entering different reaction areas of the reactor does not need to control the carbon content respectively or the catalyst with different carbon content is not needed to react in different reaction areas, or the temperature of the catalyst entering different reaction areas is not needed to be obviously different, the regenerator adopts a conventional coke oven regeneration mode, the lower regeneration area is a fast fluidized bed, the upper regeneration area is a dense-phase fluidized bed, and the catalyst is provided for the reactor from the dense-phase fluidized bed;

when the catalyst entering different reaction areas of the reactor needs to control the carbon content respectively or the catalyst with different carbon content needs to be used for reaction in different reaction areas, or the catalyst temperature needs to be obviously different in different reaction areas, the regenerator adopts an upper-lower double-dense-phase fluidized bed regeneration mode, and the catalyst amount in the two fluidized bed regeneration areas or the amount of the entering burnt oxygen or air is regulated and controlled so that the catalyst temperature and the carbon content in the two regeneration areas are different, and the catalyst with different carbon content and temperature is provided from the dense-phase fluidized bed to the reactor from different fluidized beds according to the requirement;

The stripped catalyst to be regenerated enters an upper regeneration zone, the catalyst in the upper regeneration zone is a semi-regeneration agent with moderate carbon content, the catalyst in the lower regeneration zone is a regenerated catalyst, and the temperature of the upper regeneration zone is higher than that of the lower regeneration zone; providing a catalyst from an upper regeneration zone to a catalytic cracking upper reaction zone of the reactor, and providing a catalyst from a lower regeneration zone to a catalytic cracking lower reaction zone;

the reaction zone under catalytic cracking is mainly used for catalytic conversion of macromolecular heavy oil; the upper reaction zone of catalytic cracking mainly carries out the reaction of cracking to prepare ethylene, propylene and aromatic hydrocarbon.

In the method, the circulating oil separated from the reaction product in the fractionating tower, including heavy circulating oil and light circulating oil, can be hydrogenated and then returned to the reactor; the heavy cycle oil is hydrogenated and then reacted in a reaction zone under catalytic cracking; the light cycle oil is reacted in the reaction zone under catalytic cracking, or directly enters the reaction zone on catalytic cracking, or enters the second reactor.

The invention also provides a device for realizing the method, which adopts the following scheme:

the device for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon is provided with a reactor, a regenerator, a settler and a stripping section, wherein the regenerator and the settler are arranged in parallel, the reactor is arranged in the form of an upper-lower partition reactor with two paths of catalyst circulation and two heat supplies, and comprises a lower catalytic cracking lower reaction zone and an upper catalytic cracking upper reaction zone, the lower catalytic cracking reaction zone is used for low-temperature catalytic cracking reaction, and the upper catalytic cracking reaction zone is used for high-temperature olefin cracking reaction; a heavy petroleum hydrocarbon inlet is arranged at the lower part of the catalytic cracking lower reaction zone; the lower regenerant inlet at the lower part of the catalytic cracking lower reaction zone is communicated with the lower regenerant outlet of the regenerator through a lower regeneration vertical pipe, and the upper regenerant inlet at the lower part of the catalytic cracking upper reaction zone is communicated with the upper regenerant outlet of the regenerator through an upper regeneration vertical pipe.

When the device for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon is implemented, the regenerator adopts two zones which are arranged in series up and down, the upper regeneration zone is in a fluidized bed form, the lower regeneration zone, namely a lower regeneration zone and an upper regeneration zone, are arranged below a dilute phase zone of the regenerator, and a lower regenerant outlet and an upper regenerant outlet are both arranged in the upper regeneration zone, so that regenerant is provided for the reactor through the upper regeneration zone; or an upper regeneration zone and a lower regeneration zone, namely a lower regeneration zone and an upper regeneration zone, are arranged below a dilute phase zone of the regenerator, and the upper regeneration zone is a dense phase fluidized bed regeneration zone; the lower regenerant outlet is arranged in the lower regeneration zone to provide the catalyst, namely the lower regenerant, to the catalytic cracking lower reaction zone through the lower regeneration zone, and the upper regenerant outlet is arranged in the upper regeneration zone to provide the catalyst, namely the upper regenerant, to the catalytic cracking upper reaction zone through the fluidized bed regeneration zone of the upper regeneration zone.

The device for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon is further provided with a second reactor, wherein the second reactor and the reactor share a settler, a stripping section and a regenerator; a light hydrocarbon inlet is arranged at the lower part of the second reactor; a third regenerant inlet at the lower part of the second reactor is communicated with a third regenerant outlet of the regenerator through a third regeneration vertical pipe; in practice, the third regenerant outlet is preferably provided in the upper regeneration zone. The second reactor is used for realizing independent reaction of light hydrocarbon.

In the invention, the steam in the low-temperature reaction zone accounts for 5-30% of the mass ratio of the heavy petroleum hydrocarbon, and the steam in the high-temperature reaction zone accounts for 15-50% of the mass ratio of the heavy petroleum hydrocarbon.

In the concrete implementation, a steam generator can be arranged behind the product outlet of the reaction settler, steam is generated by utilizing the heat of the high-temperature product stream, cooling or quenching of the product stream is realized, and the engineering design unit of the steam generator is mastered.

Effects of the invention

The invention provides a method for preparing olefin by gradually heating and converting with two-stage temperature gradient from a catalytic cracking mechanism. As known to those skilled in the art, the heavy oil catalytic cracking process can be regarded as parallel sequential reaction, heavy oil macromolecules (more than or equal to C18) are firstly cracked to generate intermediate molecular (C5-C12) products such as gasoline, diesel oil and the like, and the lower cracking temperature can highlight the catalytic cracking reaction, and is generally 490-530 ℃; part of gasoline and diesel oil is continuously cracked into C3-C8 at 525-600 ℃; at higher temperature, 600-750 ℃, C3-C8 will be further cracked into small molecule products of C1, C2, C3. The invention follows the reaction rule, and sets up two stages of temperature gradients which gradually rise in series: a low temperature region and a high temperature region. The invention reduces the yield of low-value target products such as coke and dry gas on the premise of lower energy consumption; the yield of high-value target products such as ethylene is improved.

The method of the invention realizes the control of the agent-oil ratio and the temperature in the reaction process, in particular to realize the gradual increase of the agent-oil ratio and the temperature along with the reaction, and the gradual increase of the reaction severity, so that the reaction conditions are adapted to the reaction chemical conditions of gradually smaller petroleum hydrocarbon molecules and gradually increased reaction severity in the cracking process of heavy petroleum hydrocarbon; the invention also well optimizes the common conversion effect of the raw materials with different properties of heavy components and light hydrocarbons, avoids the excessive cracking of small molecular light hydrocarbons, ensures the recombination and cracking conditions and ensures the light hydrocarbon cracking conditions; the method improves the efficiency and the selectivity of the target product.

Drawings

FIG. 1 is a schematic process diagram of an embodiment of the present invention;

FIG. 2 is a schematic diagram of a second embodiment of the present invention;

FIG. 3 is a schematic view of a third process according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a fourth process according to an embodiment of the present invention;

the numbering in the figures illustrates:

an R10 reactor; r11 catalyst pre-lift gas; the R11A catalyst pre-lift gas inlet, R12 heavy petroleum hydrocarbon; an R12A heavy petroleum hydrocarbon inlet, an R13 raw material atomizing steam, an R14 lower regeneration slide valve, an R14A lower regenerant inlet, an R15A lower reaction zone supplementing steam, an R15B upper reaction zone supplementing steam, an R17 catalytic cracking lower reaction zone, an R18 catalytic cracking upper reaction zone, an R19 reactor supplementing heavy oil or recycle oil, an R20 second reactor or light hydrocarbon reactor, and an R21 second catalyst pre-lifting gas; r22 light hydrocarbon; r23 light hydrocarbon atomizing steam; a regeneration slide valve on R24, a regenerant inlet on R24A; the R29 second reactor is used for supplementing heavy oil or recycle oil, the R34 third regenerating slide valve and the R34A third regenerant inlet;

S10 stripping section, S11 stripping component; s12, a spent catalyst slide valve, a spent riser or a spent catalyst conveying pipe, S12A, steam stripping, S13; s19, stripping the complementary heavy oil or recycle oil;

d10 settler, D11 settling cyclone; d12 reaction product, D12A reaction settler product outlet;

a G10 regenerator, a G11 catalyst regeneration gas, a G11A regeneration gas inlet, a G12 upper regeneration zone, a G12A spent agent inlet, a G13 fuel oil, a G14 lower regeneration vertical pipe or a lower regenerant conveying pipe, a G14A lower regenerant outlet, a G15 regenerator dilute phase zone, a G16 regeneration cyclone separator, a G17 burnt flue gas, a G17A flue gas outlet, a G18 second regeneration gas and a G19 lower regeneration zone;

a regeneration vertical pipe or an upper regenerant conveying pipe on the G24A, and a regenerant outlet on the G24A; a G34 third regeneration riser, a G34A third regenerant outlet;

an A0 heating furnace, an A1 heat exchanger, a T10 fractionating tower and a T20 hydrogenation reactor; HCO heavy cycle oil, LCO light cycle oil, CO-H hydrogenation cycle oil; h ₂ Hydrogen gas;

TIC temperature display control; controlling the outlet temperature of the reaction zone under TIC-1, controlling the outlet temperature of the reaction zone on TIC-2, and controlling the outlet temperature of the second reactor of TIC-3.

Detailed Description

The following detailed description and examples illustrate the technical aspects of the present invention, but the scope of the present invention is not limited thereto.

Embodiment one:

the method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon in the embodiment adopts a catalytic conversion device shown in fig. 1, a reactor R10, a regenerator G10, a settler D10 and a stripping section S10 are arranged, and heavy petroleum hydrocarbon is adopted as raw materials, wherein the heavy petroleum hydrocarbon can be one or a mixture of vacuum wax oil, residual oil, coker wax oil, deasphalted oil, hydrotreated wax oil, hydrotreated residual oil and crude oil when the method is implemented, and the boiling point of the heavy petroleum hydrocarbon is preferably higher than 320 ℃;

the regenerator G10 and the settler D10 are arranged in parallel, the outlet of the reactor R10 is communicated with a sedimentation cyclone separator D11 in the settler D10, the stripping section S10 is arranged below the settler D10, a stripping component S11 is arranged in the stripping section S10, and stripping steam S13 is introduced into the stripping section S10 to realize catalyst stripping;

the reactor R10 is arranged in the form of an upper-lower partition reactor with two paths of catalyst circulation and two times of heat supply, and comprises a lower catalytic cracking lower reaction zone R17 and an upper catalytic cracking upper reaction zone R18, wherein the lower catalytic cracking reaction zone R17 is used for low-temperature catalytic cracking reaction, and the upper catalytic cracking reaction zone R18 is used for high-temperature olefin cracking reaction; the lower regenerant inlet R14A at the lower part of the catalytic cracking lower reaction zone R17 is communicated with the lower regenerant outlet G14A of the regenerator G10 through a lower regeneration vertical pipe G14, and the upper regenerant inlet R24A at the lower part of the catalytic cracking upper reaction zone R18 is communicated with the upper regenerant outlet G24A of the regenerator G10 through an upper regeneration vertical pipe G24; a heavy petroleum hydrocarbon inlet R12A is arranged at the lower part of the reactor R10 to introduce heavy petroleum hydrocarbon R12 and raw material atomization steam R13, and a catalyst pre-lifting gas inlet R11A is arranged at the bottom of the reactor R10 to introduce catalyst pre-lifting gas R11; the top of the settler D10 is provided with a reaction settler product outlet D12A for leading out a reaction product D12;

In the specific implementation, the regenerator G10 adopts two zones which are arranged in series up and down for regeneration, an upper regeneration zone G19 and a lower regeneration zone G12 are arranged below a dilute phase zone G15 of the regenerator, in the specific implementation, the lower regeneration zone G19 adopts a rapid fluidized bed mode of a coke oven, the upper regeneration zone G12 adopts a dense phase fluidized bed mode, namely, the regenerator G10 adopts a series regeneration mode of the rapid fluidized bed of the coke oven and the dense phase fluidized bed, and a lower regenerant outlet G14A and an upper regenerant outlet G24A are arranged in the upper regeneration zone G12 to realize that regenerant is provided for the reactor R10 through the upper regeneration zone G12; the lower part of the stripping section S10 is communicated with a lower regeneration zone G19 of the regenerator G10 through a spent riser S12A through a spent agent inlet G12A, and a spent catalyst slide valve S12 is arranged on the spent riser S12A;

in the concrete implementation, an upper regeneration zone G12 of the regenerator G10 is communicated with a lower regeneration agent inlet R14A at the lower part of a catalytic cracking lower reaction zone R17 through a lower regeneration vertical pipe G14 by a lower regeneration agent outlet G14A, and a lower regeneration slide valve R14 is arranged on the lower regeneration vertical pipe G14;

the upper regeneration zone G12 is communicated with an upper regenerant inlet R24A at the lower part of the catalytic cracking upper reaction zone R18 through an upper regenerant outlet G24A by an upper regeneration vertical pipe G24, and an upper regeneration slide valve R24 is arranged on the upper regeneration vertical pipe G24;

A regeneration cyclone separator G16 is arranged in a regenerator dilute phase zone G15 of the regenerator G10, flue gas G17 after the regenerator is burnt is discharged from a flue gas outlet G17A at the top of the regenerator G10, and catalyst regeneration gas G11 is introduced from a regeneration gas inlet G11A at the bottom of the regenerator G10; the second regeneration gas G18 is introduced into the regenerator G10 from the lower part of the upper regeneration zone G12;

introducing lower reaction zone supplemental steam R15A above a lower regenerant inlet R14A at the lower part of a catalytic cracking lower reaction zone R17, and introducing upper reaction zone supplemental steam R15B above an upper regenerant inlet R24A at the lower part of a catalytic cracking upper reaction zone R18; a reactor is introduced to supplement heavy oil or recycle oil R19 at the downstream of a reaction zone R18 on catalytic cracking, and a stripping section S10 is introduced to supplement heavy oil or recycle oil S19, so that the increase of raw coke heat supplement and oil gas cooling are realized; the fuel oil G13 is introduced into the lower portion of the lower regeneration zone G19.

In the invention, the catalyst of the regenerator G10 respectively enters a catalytic cracking lower reaction zone R17 and a catalytic cracking upper reaction zone R18, and gradual temperature rise in the reaction process is realized by a graded heat supply mode; the specific implementation process comprises the following steps:

(1) The preheated heavy petroleum hydrocarbon R12 is atomized by the raw material atomization steam R13 and then enters a catalytic cracking lower reaction zone R17 at the lower part of a reactor R10, a lower catalyst from a lower regeneration vertical pipe G14 and an upper regeneration zone G12 of the regenerator enters the catalytic cracking lower reaction zone R17 from a lower regenerant inlet R14A, the heavy petroleum hydrocarbon R12 is conveyed upwards to be contacted with the raw material under the action of a catalyst pre-lifting gas R11, and catalytic cracking conversion is carried out on the heavy petroleum hydrocarbon R12 under a mild condition in a catalyst environment to form an intermediate product mainly comprising C5-C12; the reaction temperature of the reaction zone R17 under catalytic cracking is 525-620 ℃ and the reaction time is 0.5-5.0 s;

(2) After the heavy petroleum hydrocarbon R12 completes the low-temperature catalytic cracking reaction, then the product generated in the catalytic cracking lower reaction zone R17 flows upwards to enter the catalytic cracking upper reaction zone R18 together with the catalyst, the new catalyst, namely, the upper regenerant introduced from the regenerator G10 through the upper regeneration vertical pipe G24 enters the catalytic cracking upper reaction zone R18, is conveyed to the catalytic cracking upper reaction zone R28 by the material flow from the catalytic cracking lower reaction zone R17, the new catalyst further provides heat for the catalytic cracking upper reaction zone R18, the material flow temperature and the catalyst-oil ratio are improved, high-temperature cracking reaction conditions with higher severity are formed, the product from the catalytic cracking lower reaction zone continues to carry out catalytic cracking and thermal cracking combined reaction, and low-carbon number small molecular products such as ethylene, propylene and the like; the reaction temperature of the upper catalytic cracking reaction zone R18 is 550-750 ℃, the reaction time is 0.1-5.0 s, the absolute pressure of the reaction pressure is 0.20-0.40 MPa, and the actual reaction temperature is controlled by the amount of catalyst entering the upper catalytic cracking reaction zone R18;

(3) The reacted material flow enters a settler D10 for gas-solid separation to obtain a reaction product D12, and the reaction product D12 is sent out from a reaction settler product outlet D12A to enter a subsequent treatment part; after being separated by a settling cyclone D11, the reacted catalyst enters a lower regeneration zone G19 of the regenerator G10 through a spent riser S12A and a spent agent inlet G12A after being stripped in a stripping section S10, and is regenerated and recycled.

In the specific implementation, after the reaction product D12 leaves the catalytic conversion device shown in FIG. 1, quenching and cooling are firstly carried out, the continuous reaction is terminated, the subsequent treatment and the coking of a conveying pipeline are avoided, and then the product fractionation is carried out; quenching of the product gas can be realized by directly producing steam, or quenching can be realized by directly mixing and quenching other heat exchange and low-temperature media; quenching, fractionation, etc. are well known to the engineering skilled artisan.

In specific implementation, the raw oil can be heated by a heating furnace.

Example 1

The device and the process for preparing olefin by catalytic conversion of heavy petroleum hydrocarbon as raw material in a certain factory are shown in figure 1, and the implementation parameters are as follows: the heavy petroleum hydrocarbon is decompressed wax oil, the density is 0.89, the hydrogen content is 13.2 percent (weight), the residual carbon is 4.0 percent, and the saturated hydrocarbon is 60 percent;

the preheating temperature of the raw oil is 220 ℃;

the reaction device is formed by arranging a settler and a regenerator in parallel, the regenerator adopts a serial regeneration mode of a quick fluidized bed of a coke burning tank and a dense phase fluidized bed, and the reactor is a riser reactor;

reaction conditions in the reaction zone under catalytic cracking: the reaction temperature TIC-1 is controlled at 530 ℃ and the reaction time is 1.1s (seconds); the catalyst conveying gas is steam, the quantity is 3% of heavy petroleum hydrocarbon, and the raw material atomizing steam is 7% of the raw material; the catalyst (namely, the lower regenerant) entering from the inlet of the lower regenerant is the regenerant, the carbon content is 0.02 percent, and the temperature of the lower regenerant is 720 ℃;

Reaction conditions in the reaction zone on catalytic cracking: the catalyst (i.e. the upper regenerant) entering from the upper regenerant inlet is regenerant, the carbon content is 0.02%, the temperature is 725 ℃, the reaction temperature is 665 ℃ and the reaction time is 1.2 seconds, the steam proportion is 30%, and the supplementary steam is 20% of the raw material;

the reaction process is as follows:

the raw materials are atomized by steam and then enter a catalytic cracking lower reaction zone, and heavy oil catalytic cracking conversion is carried out under the heat provided by a lower regenerant and a catalyst environment, so that the cracking conversion of heavy oil macromolecules into intermediate molecules is realized, intermediate component raw materials with the molecular weight of 100-200 are obtained as far as possible, and intermediate raw materials are provided for further conversion into propylene and ethylene; the gas material flow and the catalyst generated in the reaction zone under the catalytic cracking continue to flow upwards to enter a high-temperature reaction zone; the high-temperature catalyst from the regenerator, namely an upper catalyst, enters a catalytic cracking upper reaction zone, is upwards conveyed into the high-temperature reaction zone by gas from a low-temperature reaction zone, further provides heat for the high-temperature reaction zone, improves the reaction temperature in the high-temperature reaction zone, and realizes the conversion reaction of the intermediate component into olefin by combining catalytic reaction and thermal reaction; the reactant flow in the high-temperature reaction zone is subjected to gas-solid separation in a settler through a gas-solid separator, and the gas from which the catalyst is separated flows out of the settler and enters a subsequent treatment system;

The catalyst to be regenerated is separated in the settler, and then enters a regenerator to carry out catalyst regeneration after being stripped in a stripping section, and the catalyst is firstly conveyed to an upper regeneration zone by burnt gas and then enters the reactor for recycling after being regenerated;

the regeneration of the catalyst, the gas-solid separation and the subsequent oil and gas treatment are common techniques, and are well known to the skilled person and will not be described again.

Example 1 product distribution is shown in table 1:

table 1 example 1 product distribution

Component (A)	Unit (weight)
		Dry gas	34.75
Wherein:
		H	0.14
methane	11.70
		Ethane (ethane)	4.75
Ethylene	17.00
		Liquefied gas	30.67
Wherein:
		propane	2.11
Propylene	18.61
		Butane	1.39
Butene (B)	8.55
		Gasoline	13.45
Diesel oil	9.1
		Heavy oil	3.2
Coke	8.83

Embodiment two:

the method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon of the embodiment adopts a catalytic conversion device shown in fig. 2, is provided with a reactor R10, a regenerator G10, a settler D10 and a stripping section S10, and adopts heavy petroleum hydrocarbon as a raw material;

the regenerator G10 is regenerated by adopting two areas which are arranged in series up and down, the lower regeneration area G19 and the upper regeneration area G12 are both in the form of dense-phase fluidized beds, the lower part of the stripping section S10 is communicated with the upper regeneration area G12 of the regenerator G10 through a to-be-regenerated vertical pipe S12A by a to-be-regenerated agent inlet G12A, and the to-be-regenerated catalyst enters the upper dense-phase fluidized bed regeneration area, namely the upper regeneration area G12 for regeneration, and then enters the lower dense-phase fluidized bed regeneration area, namely the lower regeneration area G19 for regeneration;

The lower regeneration zone G19 of the regenerator G10 is communicated with a lower regenerant inlet R14A at the lower part of a catalytic cracking lower reaction zone R17 through a lower regenerant outlet G14A and a lower regeneration vertical pipe G14, and catalyst is provided for the catalytic cracking lower reaction zone R17 from the lower regeneration zone G19, wherein the catalyst temperature is 700 ℃, and carbon content is 0.02%; the upper regeneration zone G12 is communicated with an upper regenerant inlet R24A at the lower part of the catalytic cracking upper reaction zone R18 through an upper regenerant outlet G24A and an upper regeneration vertical pipe G24, and catalyst is provided for the catalytic cracking upper reaction zone R18 from the upper regeneration zone G12, wherein the catalyst temperature is 740 ℃, and carbon content is 0.15%; introducing fuel oil G13 in the lower part of the upper regeneration zone G12;

a heat exchanger A1, a fractionating tower T10 and a hydrogenation reactor T20 are arranged on a gas lead-out line of a reaction product D12; the heavy petroleum hydrocarbon R12 and the reaction product D12 exchange heat in the heat exchanger A1, the heavy petroleum hydrocarbon R12 enters the reactor R10 to participate in catalytic conversion after being preheated, the reaction product D12 sequentially passes through the fractionating tower T10 and the hydrogenation reactor T20 after being subjected to heat exchange and temperature reduction by the heat exchanger A1, the heavy circulating oil HCO obtained by separation in the fractionating tower T10 is sent out of the device, the light circulating oil LCO is hydrogenated to become hydrogenated circulating oil CO-H, and the hydrogenated circulating oil CO-H returns to the reactor R10 from the upper part of the heavy petroleum hydrocarbon inlet R12A to be subjected to catalytic conversion again.

The other part of the device structure is the same as that of the first embodiment. The component separation and fractionation column, and the hydrogenation of the cycle oil are well known to the skilled artisan and will not be described in detail.

Embodiment III:

the method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon in the embodiment adopts a catalytic conversion device shown in fig. 3, a reactor R10, a regenerator G10, a settler D10 and a stripping section S10 are arranged, heavy petroleum hydrocarbon and light hydrocarbon are adopted as reaction raw materials, the light hydrocarbon is naphtha, one or mixture of hydrogenated catalytic cracking diesel, C4 and C5 components, and the boiling point is lower than 360 ℃;

the lower regeneration zone G19 of the regenerator G10 is communicated with a lower regenerant inlet R14A at the lower part of the catalytic cracking lower reaction zone R17 through a lower regenerant outlet G14A by a lower regeneration vertical pipe G14, and a catalyst is provided from the lower regeneration zone G19 to the catalytic cracking lower reaction zone R17; the upper regeneration zone G12 is communicated with an upper regenerant inlet R24A at the lower part of the catalytic cracking upper reaction zone R18 through an upper regenerant outlet G24A by an upper regeneration vertical pipe G24, and a catalyst is provided from the upper regeneration zone G12 to the catalytic cracking upper reaction zone R18;

Introducing fuel oil G13 in the lower part of the upper regeneration zone G12;

a light hydrocarbon inlet is arranged above an upper regenerant inlet R24A of the catalytic cracking upper reaction zone R18; a heat exchanger A1 is arranged on a gas outlet line of a reaction product D12;

the light hydrocarbon R22 and the reaction product D12 exchange heat in the heat exchanger A1, the light hydrocarbon R22 directly enters the catalytic cracking upper reaction zone R18 to participate in the reaction in the reactor R10 after being preheated, and the light hydrocarbon R22 is atomized by the light hydrocarbon atomization steam R23;

in the specific implementation, the heavy petroleum hydrocarbon R12 firstly enters a reaction zone R17 under catalytic cracking to carry out low-temperature reaction; the product and the catalyst in the catalytic cracking lower reaction zone R17 flow upwards to enter the catalytic cracking upper reaction zone R18, flow upwards together with the light hydrocarbon R22, and perform high-temperature reaction with temperature rise;

the other part of the device structure is the same as that of the first embodiment.

Embodiment four:

the method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon of the embodiment adopts a catalytic conversion device shown in fig. 3, is provided with a reactor R10, a regenerator G10, a settler D10 and a stripping section S10, adopts heavy petroleum hydrocarbon and light hydrocarbon as reaction raw materials, and adopts light hydrocarbon as hydrocracking tail oil; the hydrocracking tail oil is a technical term which is fixedly and well known in the art, after the crude oil is subjected to hydrocracking treatment, the tail oil, namely, the saturated hydrocarbon (mainly C20-C30 normal alkane) content of the hydrocracking tail oil is up to more than 96.8%, the aromatic hydrocarbon content is less than 1%, the impurity content of sulfur, nitrogen and metal and the like is low, the hydrocracking tail oil is high-quality oil, the property of the hydrocracking tail oil is related to the raw oil adopted in the hydrocracking process, and the BMCI value of the hydrocracking tail oil which can be subjected to catalytic conversion in the specific implementation process is less than or equal to 20;

The regenerator G10 is in a serial regeneration mode of a quick fluidized bed of a coke burning tank and a dense phase fluidized bed;

a second reactor R20 is arranged, and the second reactor R20 and the reactor R10 share a settler D10, a stripping section 10 and a regenerator G10; the third regenerant inlet R34A at the lower part of the second reactor R20 communicates with the third regenerant outlet G34A of the regenerator G10 via a third regenerant riser G34; the third regenerant outlet G34A is arranged in the upper regeneration zone G12; a light hydrocarbon inlet is arranged at the lower part of the second reactor R20 to introduce light hydrocarbon R22, and a second catalyst pre-lifting gas R21 is introduced at the lower part of the second reactor R20;

the second reactor R20 is used for realizing independent reaction of the light hydrocarbon R22, and heavy oil or recycle oil R29 is supplemented by introducing the second reactor into the downstream of the second reactor R20;

introducing fuel oil G13 in the lower part of the upper regeneration zone G12;

setting a heating furnace A0, preheating light hydrocarbon R22 in the heating furnace A0, then entering a second reactor R20 to realize independent catalytic conversion, enabling a material flow formed by the reaction in the second reactor R20 and a material flow formed by the reaction in the reactor R10 to enter a settler D10 together, and separating out a catalyst to obtain a reaction product D12;

preheating heavy petroleum hydrocarbon R12 in a heating furnace A0, and then entering a reactor R10 to participate in catalytic conversion;

In this embodiment, the hydrocracking tail oil density is 0.82 and the bmci value is 10.6; the amount of hydrocracking tail oil is 10% of the heavy petroleum hydrocarbon; the other part of the device structure is the same as that of the first embodiment.

Claims

1. A method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon is characterized in that a reactor (R10) is arranged into an upper reaction zone and a lower reaction zone, namely a catalytic cracking lower reaction zone (R17) and a catalytic cracking upper reaction zone (R18), heavy petroleum hydrocarbon (R12) sequentially enters the catalytic cracking lower reaction zone (R17) at low temperature and the catalytic cracking upper reaction zone (R18) at high temperature to sequentially realize low-temperature catalytic cracking reaction and high-temperature cracking reaction, and a catalyst of a regenerator (G10) respectively enters the catalytic cracking lower reaction zone (R17) and the catalytic cracking upper reaction zone (R18) to realize gradual temperature rise of a reaction process in a staged heat supply mode; the reaction process comprises the following steps:

(1) The heavy petroleum hydrocarbon (R12) is atomized by steam and then enters a catalytic cracking lower reaction zone (R17) at the lower part of the reactor (R10), and catalytic cracking reaction is carried out in a lower regenerant environment introduced from the regenerator (G10) through a lower regeneration vertical pipe (G14); the reaction temperature of the reaction zone (R17) under catalytic cracking is 525-620 ℃, the reaction temperature is controlled by the regeneration dosage from the lower regeneration vertical pipe (G14), and the reaction time is 0.5-5.0 s;

(2) After the heavy petroleum hydrocarbon (R12) completes the low-temperature catalytic cracking reaction, the product and the catalyst generated in the catalytic cracking lower reaction zone (R17) flow upwards to enter the catalytic cracking upper reaction zone (R18), and the upper regenerant introduced from the regenerator (G10) through the upper regeneration vertical pipe (G24) enters the catalytic cracking upper reaction zone (R18) to provide heat for the catalytic cracking upper reaction zone (R18), so that the temperature and the catalyst-to-oil ratio are improved, and the catalytic cracking and thermal cracking combined reaction is continued; the reaction temperature of the catalytic cracking upper reaction zone (R18) is 550-750 ℃, the reaction time is 0.1-5.0 s, and the absolute pressure of the reaction pressure is 0.20-0.40 MPa; the reaction temperature is controlled by the amount of catalyst from the upper regeneration riser (G24);

(3) The reacted material flow enters a settler (D10) for gas-solid separation to obtain a reaction product (D12), and the separated catalyst enters a regenerator (G10) for regeneration after being stripped in a stripping section (S10) for recycling.

2. The method for producing ethylene and propylene by catalytic conversion of petroleum hydrocarbon according to claim 1, wherein said heavy petroleum hydrocarbon (R12) is one or a mixture of vacuum wax oil, residual oil, coker wax oil, deasphalted oil, hydrotreated wax oil, hydrotreated residual oil, crude oil.

3. The method for producing ethylene and propylene by catalytic conversion of petroleum hydrocarbon according to claim 1, wherein said petroleum hydrocarbon feedstock further comprises a separate light hydrocarbon (R22);

or the light hydrocarbon (R22) directly enters a reactor (R10) for catalytic conversion to prepare ethylene and propylene or the light hydrocarbon (R22) enters a second reactor (R20) which is additionally arranged, the second reactor (R20) and the reactor (R10) share a settler (D10) and a regenerator (G10), and a material flow formed by the light hydrocarbon (R22) in the second reactor (R20) enters the settler (D10).

4. The method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon according to claim 3, wherein the light hydrocarbon (R22) is one or a mixture of naphtha, hydrogenated catalytic cracking diesel, C4 and C5 components, and the boiling point is lower than 360 ℃; or the light hydrocarbon (R22) is hydrocracking tail oil.

5. A process for the catalytic conversion of petroleum hydrocarbons to ethylene and propylene as claimed in claim 3, wherein said light hydrocarbon (R22) is reacted in a catalytic cracking upper reaction zone (R18) when said light hydrocarbon (R22) is reacted in the reactor (R10).

6. A process for the catalytic conversion of petroleum hydrocarbons to ethylene and propylene as claimed in claim 3, characterized in that, when said light hydrocarbons (R22) are reacted in the second reactor (R20), heavy oil or recycle oil is supplemented downstream of the second reactor (R20).

7. The method for preparing ethylene and propylene by catalytic conversion of petroleum hydrocarbon according to claim 1, wherein the temperature of the lower regenerant is 660 ℃ to 750 ℃ and the carbon content of the catalyst is lower than 0.10%; the temperature of the upper regenerant is 700-780 ℃, and the carbon content of the catalyst is lower than 0.5%.

8. The process for the catalytic conversion of petroleum hydrocarbons to ethylene and propylene according to claim 1, characterized in that the heavy oil or cycle oil is supplemented downstream of the reaction zone (R18) or/and of the stripping section (S10) on the catalytic cracking.

9. An apparatus for producing ethylene and propylene by catalytic conversion of petroleum hydrocarbon, characterized in that a reactor (R10), a regenerator (G10), a settler (D10) and a stripping section (S10) are provided, the regenerator (G10) and the settler (D10) being arranged in parallel, characterized in that:

the reactor (R10) comprises a lower catalytic cracking lower reaction zone (R17) and an upper catalytic cracking upper reaction zone (R18), wherein the lower catalytic cracking reaction zone (R17) is used for low-temperature catalytic cracking reaction, and the upper catalytic cracking reaction zone (R18) is used for high-temperature olefin cracking reaction; a heavy petroleum hydrocarbon inlet (R12A) is arranged at the lower part of the catalytic cracking lower reaction zone (R17);

the lower regenerant inlet (R14A) at the lower part of the catalytic cracking lower reaction zone (R17) is communicated with the lower regenerant outlet (G14A) of the regenerator (G10) through a lower regeneration vertical pipe (G14), and the upper regenerant inlet (R24A) at the lower part of the catalytic cracking upper reaction zone (R18) is communicated with the upper regenerant outlet (G24A) of the regenerator (G10) through an upper regeneration vertical pipe (G24).

10. The apparatus for the catalytic conversion of petroleum hydrocarbons to ethylene and propylene according to claim 9, characterized in that a second reactor (R20) is provided, said second reactor (R20) sharing a settler (D10), a stripping section (S10) and a regenerator (G10) with the reactor (R10); a light hydrocarbon inlet is arranged at the lower part of the second reactor (R20);

a third regenerant inlet (R34A) at the lower part of the second reactor (R20) is communicated with a third regenerant outlet (G34A) of the regenerator (G10) through a third regeneration vertical pipe (G34).