CN111807918A

CN111807918A - Method and device for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material

Info

Publication number: CN111807918A
Application number: CN202010658106.6A
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: 2020-10-23
Anticipated expiration: 2040-07-09
Also published as: CN111807918B

Abstract

The invention relates to a method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw materials, belonging to the technical field of catalytic conversion of petroleum hydrocarbons. The method adopts heavy petroleum hydrocarbon and hydrocracking tail oil as raw materials to produce olefin, the heavy petroleum hydrocarbon is firstly subjected to catalytic conversion in the first catalyst environment of a first reaction regeneration system, part or all of generated gas-phase products enter a second reaction regeneration system, and the gas-phase products and the hydrocracking tail oil are subjected to secondary high-temperature reaction and high-temperature reaction in the second catalyst environment to prepare the olefin. The invention arranges three-stage temperature gradient series connection of gradual temperature rise, namely a low-temperature area of a first reactor, a secondary high-temperature area of a second reactor and a high-temperature area of the second reactor, and simultaneously respectively configures proper special catalysts for low-temperature cracking and high-temperature cracking, thereby realizing double-reaction system and double-catalyst circulation and improving the yield of high-value target products.

Description

Method and device for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material

Technical Field

The invention belongs to the technical field of petroleum hydrocarbon catalytic conversion, and particularly relates to a method for preparing olefin by catalytic conversion of a petroleum hydrocarbon raw material.

Background

The low-carbon olefin represented by ethylene and propylene is the most basic raw material in chemical industry, and the existing catalytic conversion technology is used for producing gasoline and diesel oil and simultaneously producing the low-carbon olefin as a byproduct, so that the requirement of the current market on organic chemical raw materials can not be met. Aromatic hydrocarbon is an important organic chemical raw material with the yield and the scale second only to ethylene and propylene, and derivatives thereof are widely used for producing chemical products such as chemical fibers, plastics, rubber and the like and fine chemicals, and with the continuous development of petrochemical industry and textile industry, the demand of aromatic hydrocarbon in the world is continuously increased. Natural gas or light petroleum fractions are mostly used as raw materials at home and abroad, low-carbon olefin is produced by adopting a steam cracking process in an ethylene combined device, and a large amount of other basic raw materials such as olefin, aromatic hydrocarbon and the like are produced as byproducts during the production of ethylene. Although the steam cracking technology is developed for decades and the technology is continuously improved, the steam cracking technology still has the advantages of high energy consumption, high production cost and CO₂The discharge amount is large, the product structure is not easy to adjust, and other technical limitations, and the traditional technology for producing ethylene and propylene by steam cracking is facing a severe test. The catalytic conversion method is used for preparing olefin, and meanwhile, the by-products of low-carbon olefin such as propylene, butylene and the like and chemical raw materials such as aromatic hydrocarbon and the like are new directions for solving the problems of resource shortage and low-cost production of chemical products, and become important research subjects and hot problems at present.

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

1. the reaction raw material is divided into different fractions by a distillation tower, and the different fractions are respectively subjected to catalytic reaction in different reactors. For example, CN109575982A provides a method for preparing low-carbon olefins and aromatics by catalytic cracking of crude oil, which comprises desalting and dehydrating crude oil, heating in a heating furnace, and then feeding into a distillation tower to separate the crude oil into light and heavy components with a cutting point of 150-300 ℃; the light components coming out of the top of the tower and the heavy components coming out of the bottom of the tower contact and react with the high-temperature catalyst in the atmosphere of water vapor in the two reactors.

2. The materials in the reactor are fed and reacted layer by layer. For example, CN1898362 provides a method for producing light olefins and aromatics, in which a raw material is contacted with a catalytic cracking catalyst, the reaction is divided into at least two layers of feeding materials according to the nature of the raw material, and different liquid reaction products from a fractionating tower are returned to a reactor from different positions to be converted again except for target products. CN1215041A provides a method for preparing ethylene, propylene, aromatic hydrocarbon and the like by directly converting various feeding hydrocarbons, wherein a plurality of groups of feeding holes are arranged on a reactor, so that hydrocarbons with different properties enter a device from different feeding holes, and the cracking reaction is carried out under the same process conditions of all parts. CN104560154A provides a hydrocarbon catalytic conversion method for increasing the yield of light olefins and light aromatics, which comprises the following steps: contacting a heavy hydrocarbon raw material with a cracking catalyst in a first reactor to perform 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, and injecting medium hydrocarbon raw materials from the middle part of the second reactor to perform catalytic cracking reaction; and introducing the reaction mixture generated in the second reactor into a third reactor for continuous reaction, and then 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 phosphorus and transition metal M.

3. Outside the raw oil riser, additionally establishing a reactor to convert different fractions by catalysis again, namely adopting a multi-reactor form, carrying out conventional raw oil reaction in the first reactor, and feeding one or more fractions such as crude gasoline into the additionally established reactor for further conversion to obtain a target product after fractionation; for example, CN1388216 discloses a catalytic conversion method for preparing propylene, butylene and gasoline with low olefin content, comprising 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 introducing an oil agent mixture into a fluidized bed through the riser; (2) injecting gasoline into the fluidized bed, contacting and reacting with the catalyst from the riser; (3) separating the oil mixture, stripping the reacted catalyst, regenerating in a regenerator, and returning the regenerated catalyst to the riser for reuse. The method can not only increase the yield of low-carbon olefin, but also produce high-quality gasoline with low olefin content. CN1258580C discloses a method and a system for upgrading gasoline by deeply reducing olefin and increasing octane number by catalytic conversion, wherein a catalytic upgrading reactor is added in a reaction-regeneration system of a heavy oil catalytic conversion device to perform catalytic upgrading reaction on gasoline fraction by catalytic conversion. The upgraded catalytically converted gasoline fraction may be a naphtha whole fraction, a naphtha light fraction or a naphtha heavy fraction obtained by establishing a secondary condensation system at the top of the fractionator.

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

5. In order to increase the yield of the low-carbon olefin, an auxiliary catalyst suitable for cracking small-molecular hydrocarbons can be added, and the amount of the added auxiliary catalyst is generally 5-8% of that of a heavy oil reaction catalyst, and 1-1.5% of propylene can be added.

The above technologies for reducing olefins by Fluidized Catalytic Conversion (FCC) and increasing the production of chemical feedstocks have some common drawbacks as follows:

1. different raw materials require different catalysts, heavy oil cracking requires high macromolecule cracking capability of the catalyst, and generally requires a larger aperture; c4 and C5 cracking need catalysts with low carbon olefin selectivity, and generally need smaller pore diameter; the prior art processes described above all use the same catalyst, i.e., only one catalyst. Although 5-8% of auxiliary agent can be added into the regenerator to further convert small molecules in order to increase the yield of low-carbon olefins, when the auxiliary agent is added into the FCC catalyst, the cracking activity of the catalyst is inevitably reduced due to the dilution effect on the catalyst. The heavy oil cracking conversion rate is reduced by 1 percentage point per 5% of the addition of the promoter, which is an important factor that seriously affects the economy of the FCC technology, and the improvement of the objective product is limited due to the low concentration of the promoter after mixing with the heavy oil cracking catalyst.

2. Because the second reaction system needs more reaction heat and generally has less coke formation, the heat generated by the regeneration of the coke formation can not provide the heat required by the reaction, and if the independent second reaction system is established by utilizing the prior art, the heat balance problem is restricted.

3. In all the recycling methods, the fraction is separated by a fractionating tower, cooled into liquid by heat exchange and then returned to the reactor, different fractions are firstly cooled into liquid by the heat exchange of the fractionating tower, and the liquid is returned to the original reactor or is further converted by another reactor directly after separation or after proper re-preheating (still liquid). Through the processes of cooling and heating, the investment of equipment and energy consumption is increased, and the economical efficiency of the process technology is greatly reduced.

4. The preparation of ethylene from petroleum hydrocarbon requires higher reaction temperature, generally higher than 650 ℃; the reaction process of catalytically preparing olefin from catalytically cracked material oil, especially heavy material oil, is a process of gradually cracking and gradually reducing molecular weight; smaller molecules are more difficult to activate, the required reaction temperature is higher, the temperature is high, and the thermal cracking reaction is naturally performed, so that the selectivity of a target product is influenced; how to allocate the reaction temperature and the molecular characteristics of petroleum hydrocarbon well, balance the catalytic cracking reaction and the thermal cracking reaction well, and have important significance for realizing the limit control of the reaction; the expected reaction process is that the specific gravity of catalytic reaction is increased as much as possible in the large molecule cracking stage of heavy oil and the like, thermal cracking is limited, the temperature is gradually increased in the small molecule cracking stage, and the proportion of thermal cracking reaction is increased; however, in the prior art, heat is provided in the inlet area of the reactor in the reaction process, the reaction is a gradual cooling process, particularly for the reaction for preparing olefin, the reaction temperature is higher in the initial stage, namely the heavy oil cracking stage at the lower part of the reactor, and heavy components are directly subjected to thermal cracking reaction, so that the effect of catalytic cracking reaction is reduced.

CN200810140866.7 discloses a catalytic conversion method, which is sequentially performed in a first reaction system and a second reaction system, wherein all or part of fractions generated after raw oil enters the first reaction system for catalytic reaction enter the second reaction system in a gas and/or liquid form for further catalytic reaction, and the first reaction system and the second reaction system respectively use corresponding catalysts according to the difference between the reaction raw material and the target product. The method overcomes the defects of poor selectivity, low auxiliary agent content, dilution effect on the catalyst and the like when a single catalyst is adopted by using two reaction systems and using a specific catalyst to carry out selective catalytic conversion on different fractions. However, the following problems still remain in this method:

no matter the raw oil of the first reaction system is cracked, or the gas-phase intermediate component of the second reaction system is further catalytically cracked, the heat in the reaction process is still provided in the inlet area of the reactor, the reaction is a gradual temperature rise process, the molecules are gradually reduced in the continuous reaction process of the intermediate component, and the heat condition for re-cracking the small molecules is insufficient in the rear section of the reactor, so that the production of high-value product ethylene is greatly reduced.

In addition, with the increasing of the crude oil weight and the increasing of the demand for clean fuels, China has built a plurality of large hydrocracking units, and the hydrocracking processing capacity is higher. Before the cracking reaction, the raw material is hydrorefined to remove non-hydrocarbon impurities of sulfur, nitrogen and the like, and simultaneously the reactions of aromatic saturation, ring opening, dealkylation, isomerization and the like are carried out, so that after the crude oil is subjected to hydrocracking treatment, the content of tail oil, namely hydrocracking tail oil saturated hydrocarbon (mainly C20-C30 normal paraffin) is up to over 96.8 percent, the content of aromatic hydrocarbon is less than 1 percent, and the content of impurities of sulfur, nitrogen, metal and the like is low, thus the high-quality oil is obtained. The hydrocracking tail oil is reasonably utilized, and the method is a new choice for oil refining enterprises. Compared with heavy petroleum hydrocarbon, the hydrocracking tail oil is easy to produce ethylene by catalytic cracking at high temperature due to long chain and high hydrocarbon content, and accounts for 10-30% of the raw materials for producing ethylene.

Disclosure of Invention

The invention aims to provide a method for preparing olefin by catalytic conversion of a petroleum hydrocarbon raw material on the basis of the prior art, which takes a heavy petroleum hydrocarbon raw material and hydrocracking tail oil as raw materials, adopts a double-reaction regeneration system and arranges an upper and a lower subarea reactors in a second reaction regeneration system, and carries out gradual temperature rise, three-stage temperature gradient double catalysis and gas phase relay catalytic conversion on the heavy petroleum hydrocarbon raw material and the hydrocracking tail oil, thereby realizing high-yield preparation of the olefin, and having low equipment investment and low energy consumption. The invention also provides a device for preparing olefin by catalytic conversion of the petroleum hydrocarbon raw material.

The invention adopts the following technical scheme:

a method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material, taking heavy petroleum hydrocarbon and hydrocracking tail oil as raw materials, carrying out catalytic conversion in a first reaction regeneration system and a second reaction regeneration system to prepare olefin, wherein the first reaction regeneration system uses a first catalyst, and the second reaction regeneration system uses a second catalyst; the method comprises the following steps:

(1) the method comprises the steps that heavy petroleum hydrocarbon is firstly subjected to catalytic conversion in a first reaction regeneration system, enters a first reactor, and is subjected to catalytic cracking reaction in the environment of a first catalyst from the first regenerator, wherein the reaction temperature of an outlet of the first reactor is 490-600 ℃, the reaction time is 0.5-5.0 s, and the absolute pressure of the reaction pressure is 0.23-0.50 MPa; after a material flow formed by the reaction of the first reactor enters a first settler and a first catalyst is separated out, a first reaction system product is formed; the first catalyst separated by the first settler enters a first regenerator for regeneration after being stripped in a first stripping section, and is recycled; the first reactor outlet reaction temperature is optimized to 490 c to 550 c when propylene is the objective and ethylene is minimized.

(2) The first reaction system product or the light component of the first reaction system product after heavy component separation and the hydrocracking tail oil R32 enter a second reaction regeneration system for catalytic conversion;

and the first reaction system product or the light component of the first reaction system product and the hydrocracking tail oil enter a second reactor of an upper partition and a lower partition of a second reaction regeneration system to perform catalytic conversion in any mode:

the first catalytic conversion mode is as follows: the first reaction system product or the light component of the first reaction system product firstly enters the bottom of a secondary high-temperature reaction zone of a second reactor, the secondary high-temperature reaction mainly comprising the catalytic cracking of the heavy component or the larger molecule and the intermediate component is carried out under the environment of a second catalyst I (or called a second regenerant I or a second regenerated catalyst I) introduced from a second regenerator through a second regeneration vertical pipe I, the reaction temperature is 520-600 ℃, the reaction time is 0.1-5.0 s, the reaction pressure is 0.20-0.40 MPa, the actual reaction temperature is controlled by the catalyst entering the secondary high-temperature reaction zone, the product and the catalyst in the secondary high-temperature reaction zone flow upwards to enter the high-temperature reaction zone of the second reactor, are mixed with the hydrocracking tail oil directly entering the high-temperature reaction zone, and the combined high-temperature reverse reaction of the catalytic cracking and the thermal cracking with the increased temperature is carried out under the environment of a second catalyst II (or called a second regenerant II or a second regenerated catalyst II) introduced from the second regenerator through the second regeneration vertical pipe II The conversion of the intermediate component into ethylene and propylene is realized to form ethylene, the reaction temperature 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 the catalyst entering a high-temperature reaction zone;

and a second catalytic conversion mode: the first reaction system product or the light component of the first reaction system product directly reacts in a high-temperature reaction zone, the hydrocracking tail oil firstly enters a secondary high-temperature reaction zone for secondary high-temperature reaction, then flows upwards with a catalyst to enter the high-temperature reaction zone, and is mixed with the first reaction system product or the light component of the first reaction system product directly entering the high-temperature reaction zone for high-temperature reaction; and (3) a catalytic conversion mode III: directly feeding the first reaction system product or the light component of the first reaction system product and the hydrocracking tail oil into a secondary high-temperature reaction zone for secondary high-temperature reaction, and then feeding the product and the catalyst upwards to the high-temperature reaction zone for continuous reaction;

after the material flow formed by the reaction in the second reactor enters a second settler and the catalyst is separated out, a second reaction system product mainly comprising ethylene, propylene and aromatic hydrocarbon is obtained; the catalyst separated by the second settler enters a second regenerator for regeneration after being stripped in a second stripping section, and is recycled;

or the first reaction system product or the light component of the first reaction system product enters a second reactor of an upper and lower subarea of a second reaction regeneration system, and reacts in a secondary high-temperature reaction zone and a high-temperature reaction zone in sequence, and meanwhile, the hydrocracking tail oil reacts in a third reactor independent of the second reaction regeneration system; the method comprises the following steps that a first reaction system product or a light component firstly enters the bottom of a secondary high-temperature reaction zone, a secondary high-temperature reaction is carried out in the environment of a second catalyst I introduced from a second regenerator through a second regeneration vertical pipe I, a product and a catalyst in the secondary high-temperature reaction zone flow upwards and enter the high-temperature reaction zone, a high-temperature reaction with the temperature increased is carried out in the environment of a second catalyst II introduced from the second regenerator through a second regeneration vertical pipe II, hydrocracking tail oil enters the lower part of a third reactor, a major molecular catalytic cracking high-temperature reaction is carried out in the environment of a second catalyst III (or called second regenerant III or second regenerated catalyst III) introduced from the second regenerator through a second regeneration vertical pipe III, and the third reactor has the reaction temperature of 550-720 ℃, the reaction time of 0.5-5.0 s and the absolute pressure of 0.2-0.4 MPa; after the material flow formed by the reaction of the second reactor and the third reactor enters a second settler and the catalyst is separated out, a second reaction system product mainly comprising ethylene, propylene and aromatic hydrocarbon is obtained; and the catalyst separated by the second settler enters a second regenerator for regeneration after the second stripping section carries out steam stripping, and is recycled.

When propylene is taken as a target and ethylene is reduced as much as possible, the reaction temperature of the secondary high-temperature reaction zone is 520-560 ℃, and the reaction temperature of the high-temperature reaction zone is 550-570 ℃;

the gas flow velocity in the secondary high-temperature reaction zone is 0.6-25 m/s, and the gas flow velocity in the high-temperature reaction zone is 0.6-30 m/s.

In the method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material, the heavy component of the product of the first reaction system is separated by a separation tower or a fractionating tower to form the light component of the product of the first reaction system, and the light component of the product of the first reaction system enters the second reaction regeneration system in a gas phase state.

In the method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material, the heavy petroleum hydrocarbon raw material is one or a mixture of vacuum wax oil, residual oil, coker wax oil, deasphalted oil, hydrogenated wax oil, hydrogenated residual oil, hydrogenated catalytic diesel oil, crude oil and condensate oil, and the boiling point is higher than 320 ℃.

In the method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material, the active component of the first catalyst is selected from one or a mixture of HY, USY, REY, REHY, REUSY and H-ZSM-5; the active component of the second catalyst is selected from Y-type zeolite, L-type zeolite, ZSM-5 zeolite, beta zeolite, aluminum phosphate zeolite, mordenite, or one or a mixture of modified zeolites.

The method for preparing the olefin by catalytic conversion of the petroleum hydrocarbon raw material further comprises the steps of introducing the second catalyst I into the secondary high-temperature reaction zone through the second regeneration vertical pipe I at the temperature of 660-820 ℃, and introducing the second catalyst II into the high-temperature reaction zone through the second regeneration vertical pipe II at the temperature of 700-850 ℃.

In the method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material, the carbon content of the second catalyst I introduced into the secondary high-temperature reaction zone through the second regeneration vertical pipe I is lower than 0.15%, and the carbon content of the second catalyst II introduced into the high-temperature reaction zone through the second regeneration vertical pipe II is lower than 0.5%.

In the method for producing olefins by catalytic conversion of petroleum hydrocarbon feedstock, the second regenerator of the second reaction regeneration system is further replenished with fuel.

In the method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material, further, when the light component of the product of the first reaction system enters the second reaction regeneration system, the light component of the product of the first reaction system exchanges heat with the product of the second reaction system, and the heated light component of the product of the first reaction system enters the second reaction regeneration system for reaction.

The invention also provides a device for realizing the method, and the device for preparing olefin by catalytic conversion of the petroleum hydrocarbon raw material adopts the following technical scheme one or two:

the first technical scheme is as follows: a device for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material is provided with a first reaction regeneration system and a second reaction regeneration system, wherein the first reaction regeneration system is provided with a first reactor, a first settler, a first stripping section and a first regenerator, and the lower part of the first reactor is provided with a heavy petroleum hydrocarbon inlet; the second reaction regeneration system is provided with a second reactor, a second settler, a second stripping section and a second regenerator; a material flow pipeline is arranged between the first reaction gas product outlet of the first settler and the second reactor, or a material flow pipeline is arranged between the first reaction gas product outlet and the second reactor, and a separation tower or a fractionating tower is arranged on the material flow pipeline at the same time; the first reactor and the second reactor are selected from a riser and a fluidized bed single or composite reactor;

the second reactor is arranged in the form of an upper and lower partitioned reactor with upper and lower catalyst circulation paths and twice heat supply, and comprises a lower sub-high-temperature reaction zone and an upper high-temperature reaction zone; a second regenerant I inlet at the lower part of the secondary high-temperature reaction zone is communicated with a second regenerant I outlet of the second regenerator through a second regeneration vertical pipe I, and a second regenerant II inlet at the lower part of the high-temperature reaction zone is communicated with a second regenerant II outlet of the second regenerator through a second regeneration vertical pipe II;

a hydrocracking tail oil inlet is formed in the bottom of the secondary high-temperature reaction zone, and the material flow pipeline is arranged between a first reaction gas product outlet and the bottom of the high-temperature reaction zone; or a hydrocracking tail oil inlet is arranged at the bottom of the high-temperature reaction zone, and the material flow pipeline is arranged between the first reaction gas product outlet and the bottom of the secondary high-temperature reaction zone;

the second technical scheme is as follows: a device for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material is provided with a first reaction regeneration system and a second reaction regeneration system, wherein the first reaction regeneration system is provided with a first reactor, a first settler, a first stripping section and a first regenerator, and the lower part of the first reactor is provided with a heavy petroleum hydrocarbon inlet; the second reaction regeneration system is provided with a second reactor, a second settler, a second stripping section, a second regenerator and a third reactor; a material flow pipeline is arranged between the first reaction gas product outlet of the first settler and the bottom of the second reactor, or a material flow pipeline is arranged between the first reaction gas product outlet and the bottom of the second reactor, and a separation tower or a fractionating tower is arranged on the material flow pipeline at the same time; the first reactor and the second reactor are selected from a riser and a fluidized bed single or composite reactor;

the second reactor is arranged in the form of an upper and lower partitioned reactor with upper and lower catalyst circulation paths and twice heat supply, and comprises a lower sub-high-temperature reaction zone and an upper high-temperature reaction zone; a second regenerant I inlet at the lower part of the secondary high-temperature reaction zone is communicated with a second regenerant I outlet of the second regenerator through a second regeneration vertical pipe I, and a second regenerant II inlet at the lower part of the high-temperature reaction zone is communicated with a second regenerant II outlet of the second regenerator through a second regeneration vertical pipe II; the third reactor and the second reactor share a second settler, a second stripping section and a second regenerator, and a second regenerant III inlet at the lower part of the third reactor is communicated with a second regenerant III outlet of the second regenerator through a second regeneration vertical pipe III; and a hydrocracking tail oil inlet is formed in the bottom of the third reactor.

The technical scheme of the invention is as follows:

1. in the first reaction regeneration system, heavy petroleum hydrocarbon or heavy raw oil is firstly subjected to catalytic cracking reaction in a first reactor, catalytic cracking conversion, decarburization and demetalization of heavy components and macromolecules of the heavy petroleum hydrocarbon are preliminarily completed, and intermediate components mainly comprising high-olefin gasoline and diesel oil components are generated to form an intermediate raw material for preparing olefin;

in the invention, the reaction regeneration system is known and provided with a reactor, a settler, a steam stripping section and a regenerator, wherein the outlet of the reactor is communicated with a gas-solid separation device in the settler, the steam stripping section is arranged below the settler, the lower part of the steam stripping section is communicated with the regenerator through a stand pipe to be regenerated, and the regenerator is communicated with a regenerant inlet of the reactor through a regeneration stand pipe; in the specific implementation and arrangement: the reactor and the regenerator are preferably arranged in parallel, and the reactor and the settler can be coaxially arranged or arranged in parallel; the top of the settler is provided with a product outlet of the reaction system; one or more reactors can be arranged in one set of reaction regeneration system to meet the requirements of different raw materials, and the outlets of the reactors can be communicated with the same settler to carry out gas-solid separation operation on the reacted material flow; the lower part of the reactor is provided with a petroleum hydrocarbon feed inlet (a feed nozzle when liquid phase feeding is carried out), the feed inlet is arranged above or below a regenerant inlet of the reactor, and a lifting or fluidizing medium gas inlet is arranged at the bottom of the reactor. The conventional specific arrangement and connection positions of the reactor, the settler, the stripping section and the regenerator in the reaction regeneration system, and the inlet and outlet positions and specification requirements of various material flows can be grasped by engineering technicians, and are not described in detail below. As is known, the reaction process of the reactor using a reaction regeneration system in the form of a riser is as follows: the regenerated catalyst or called regenerating agent enters the lower part of the reactor through the regeneration vertical pipe, goes upward along the reactor, petroleum hydrocarbon enters the reactor through the feed inlet, contacts with the catalyst and flows upward together to realize reaction, the material flow after the reaction enters the settler to separate the catalyst, the product flows out through the product outlet, the catalyst enters the stripping section for stripping, and the spent catalyst or called spent agent enters the regenerator through the spent vertical pipe to realize regeneration and recycle.

2. When the method is implemented specifically, heavy components are preferentially separated from the product of the first reaction system, so that the reaction efficiency of the second reaction regeneration system is improved; all or part of the separated heavy components return to the first reaction regeneration system for continuous catalytic conversion, and the heavy components which do not return to the first reaction regeneration system are sent out of the device; heavy components separated from a product of the first reaction system are subjected to hydrogenation treatment, appropriate aromatic hydrocarbon ring opening and side chain saturation are carried out, the hydrogen content is increased, the properties of the heavy components are improved, and then the heavy components are returned to the first reaction regeneration system for reaction, so that the catalytic conversion efficiency of the first reaction regeneration system is improved;

heavy components are separated, and the heavy components can be separated through cooling of a heat exchange device; or separating heavy components through a fractionation system, wherein the fractionation system is arranged on a material flow pipeline between a product outlet of the first settler and the bottom of the second reactor, the fractionation system is provided with a tower bottom reflux device or a device combining tower bottom reflux and middle heat exchange, and the fractionation system separates the heavy components through the mode combining tower bottom heat exchange or tower bottom heat exchange and middle section heat exchange; separation of heavy components is a common process and is well known to engineering designers.

3. When the heavy component separated from the product of the first reaction system returns to the first reaction system for continuous reaction, the heavy component enters the first reactor again for reaction or enters an additional independent reactor for reaction, the cutting temperature of the heavy component is controlled according to the boiling point of 350 ℃, and part or all of the components with the boiling points higher than 350 ℃ return to the first reaction regeneration system; or the heavy component cutting temperature is controlled according to the boiling point of 480 ℃, and the components with the boiling point higher than 480 ℃ are sent out of the device after being separated or returned to the first reaction regeneration system after being subjected to hydrogenation treatment.

4. In the invention, petroleum hydrocarbon raw materials react to prepare olefin under the condition of three-stage temperature gradient, firstly, heavy petroleum hydrocarbon enters a first reaction zone, namely a low-temperature reaction zone in a first reaction regeneration system to carry out cracking reaction, all or part of generated components enter a second reaction regeneration system in a gaseous state, and enter the second reaction regeneration system together with hydrocracking tail oil to carry out cracking reaction; the method comprises the following specific steps:

in the second reaction regeneration system, at least one reactor, namely the second reactor, is provided with an upper stage and a lower stage of heat supply and catalyst circulation, the second reactor is divided into an upper reaction zone and a lower reaction zone by an upper catalyst and heat supply position, namely a second regenerant II inlet, the lower part is a secondary high-temperature reaction zone, and the upper part is a high-temperature reaction zone; heat is provided by the catalyst entering the upper part of the second reactor, and the catalyst further improves the reaction temperature and the catalyst-to-oil ratio to form high-temperature reaction; the selective reaction in the upper and lower reactors of two-stage heat supply and two-stage catalyst supply is realized, the reaction mode of gradually rising reaction temperature is adapted to the molecular structure of reactants with gradually reduced molecular weight and the change of the requirement on reaction conditions, and the efficiency of olefin production and the selectivity of products at different levels are improved;

in the second reactor, the material firstly enters a secondary high-temperature reaction zone to carry out catalytic cracking reaction mainly for converting the residual heavier components or larger molecules and intermediate components to C3-C8; the product of the secondary high-temperature area and the catalyst flow upwards to enter a high-temperature reaction area, and then a new catalyst is supplemented, heat is provided, the temperature is increased, and then the combined reaction of catalytic cracking and thermal cracking is continuously carried out to generate an ethylene propylene product;

in the mode of feeding the material into the second reactor, or the hydrocracking tail oil directly reacts in the high-temperature reaction zone, or the gaseous material of the first reaction system directly reacts in the high-temperature reaction zone, or the hydrocracking tail oil and the gaseous material of the first reaction system are sequentially in the secondary high-temperature reaction zone and the high-temperature reaction zone at the same time.

5. In the invention, the temperature of the second catalyst I introduced through the second regeneration vertical pipe I and the temperature of the second catalyst II introduced through the second regeneration vertical pipe II can be the same or different; the second regenerator can adopt single-stage regeneration or multi-stage regeneration when being implemented, preferably adopt the two-stage regeneration form of upper and lower series connection used in the embodiment, the second spent catalyst from the second stripping section firstly enters a first-stage regeneration zone from the lower part of the second regenerator, contacts and reacts with the charring air, flows upwards and enters a second-stage regeneration zone to be regenerated continuously, and supplements fuel in the first-stage regeneration zone or the second-stage regeneration zone to realize regenerator heat supplement; the second regenerant II is from a second stage regeneration zone, and the second regenerant I is from either the second stage regeneration zone or the first stage regeneration zone.

6. In the first reaction regeneration system, the mass ratio of the steam used by the first reactor to the raw oil is 5-30%, in the second reaction regeneration system, the mass ratio of the supplemented steam to the second reactor to the raw oil is 5-30%, and the mass ratio of the steam to the raw oil in the reaction process of the second reaction regeneration system is 15-50%; the steam supplemented to the second reaction regeneration system is supplemented in the second high-temperature reaction zone or respectively supplemented in the second high-temperature reaction zone and the high-temperature reaction zone.

7. The treatment of the product of the second reaction system after flowing out of the second precipitator is a conventional engineering process, which relates to product quenching, heat exchange, fractionation and the like, if a steam generator can be arranged, steam is generated by utilizing the heat of high-temperature product material flow, and the engineering design unit of the steam generator is mastered; the product can be quenched and cooled by directly mixing a low-temperature medium with the product material flow; as is known to the engineer.

Has the advantages that:

the invention provides a method for preparing olefin by gradual temperature rise, three-stage temperature gradient dual catalysis and gas phase relay conversion based on a catalytic cracking mechanism. As is well known to those skilled in the art, the heavy oil catalytic cracking process can be regarded as a parallel sequential reaction, heavy oil macromolecules (C18 or more) are firstly cracked to generate middle molecular (C5-C12) products such as gasoline, diesel oil and the like, and the lower cracking temperature can highlight the catalytic cracking reaction, generally 490-530 ℃; part of gasoline and diesel oil is cracked into C3-C8 at 530-600 deg.c; at higher temperature, 600-750 ℃, C3-C8 will further crack into C1, C2, C3 small molecule products. The invention follows the reaction rule and arranges three-stage temperature gradient series connection with gradual temperature rise: a low temperature zone, a sub-high temperature zone, a high temperature zone; simultaneously, proper special catalysts are respectively prepared for low-temperature cracking and high-temperature cracking, a double reaction system is arranged, and double catalysts circulate to strive for exerting the maximum effectiveness of the catalysts; the raw material gas phase relay also provides heat for the second reaction regeneration system to make up for the heat deficiency. 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 the high-value target product olefin is improved.

Specifically, the method comprises the following steps:

the second system adopts a three-level temperature gradient scheme of two-level heat supply and formation of a low-temperature reaction of the first system and a second high-temperature and high-temperature reaction of the second system, so that the temperature is gradually increased along with the reaction, the petroleum hydrocarbon is gradually cracked, molecules are gradually reduced along with the reaction, the required cracking energy level is gradually increased, and the required temperature is gradually increased; the efficiency of cracking to olefin is improved, and the selectivity of the target product is also improved;

compared with the conventional catalytic cracking, the method of the invention can use different catalysts according to specific feeding properties and product requirements due to the fact that the catalytic conversion reaction of the heavy petroleum hydrocarbon raw material and the hydrocracking tail oil is realized through two reaction regeneration systems, so that the selectivity is increased, the efficiency is improved, for example, the heavy petroleum hydrocarbon can be subjected to decarburization, demetalization and heavy oil cracking in the first reaction system, and the catalyst suitable for small molecule reaction is used in the second reaction regeneration system for further catalytic conversion to produce propylene chemical raw materials such as ethylene and the like. In addition, all or part of fractions from the first reaction regeneration system directly enter the second reaction regeneration system in a gaseous state, so that more heat is provided for the second reaction regeneration system, the requirement on heat supply capacity is reduced, the problem of insufficient heat caused by insufficient coke generation of the second reaction regeneration system is solved, and the method that the fractions are cooled and separated firstly and then preheated and returned to the reactor is changed, so that the equipment investment is greatly saved, and the energy consumption is reduced; according to the invention, two reaction regeneration systems are used, and a specific catalyst is used for carrying out selective catalytic conversion on different raw material components, so that the defects of poor selectivity, low auxiliary agent content, dilution effect on the catalyst and the like when a single catalyst is adopted are overcome, the yield of chemical raw materials such as ethylene, propylene and the like can be improved, and the product yield can be improved;

the heavy components of the product of the first reaction system are separated, so that the selection of the catalyst of the second reaction regeneration system and the adjustment of reaction conditions are more convenient, and the catalytic cracking reaction effect of the light components and the recovery of the target product are favorably improved.

Drawings

FIG. 1 is a schematic process diagram according to one embodiment of the present invention;

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

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

the numbering in the figures illustrates:

r10 first reactor; r11 catalyst pre-lift gas; R11A catalyst pre-lift gas inlet, R12 heavy petroleum hydrocarbon; an inlet of R12A heavy petroleum hydrocarbon, atomizing steam of R13 raw material, R14 first reaction system product, an outlet of R14A first reaction gas product, R14L first reaction system product liquid heavy component, R14G first reaction system product light component, R15 first regeneration slide valve, R15A first reactor regenerant inlet, R16A first standby riser, R16 first standby slide valve, and R17 first reaction zone;

s10 first stripping section, S11 first stripping member;

a D10 first settler, a D11 first cyclone;

g10 first regenerator, G11 catalyst regeneration gas, G11A first regeneration gas inlet, G12A first regenerant inlet, G14A first regenerant outlet, G14 first regeneration standpipe; g15 first regenerator dilute phase zone, G16 first regenerator cyclone, G17 first reactor burnt flue gas, G17A first flue gas outlet;

the system comprises a R20 second reactor, a R21 times high-temperature reaction zone is supplemented with steam, a R22 second regeneration slide valve II, a R22A second regenerant II inlet, a R23 high-temperature reaction zone is supplemented with steam, a R24 second reaction system product, a R25 second regeneration slide valve I, a R25A second regenerant I inlet, a R26 second regenerant valve, a R26A second regenerant vertical pipe or a second spent catalyst vertical pipe, a R27 times high-temperature reaction zone and a R28 high-temperature reaction zone; r30 third reactor; r31 third reactor steam; r32 hydrocracked tail oil; r33 hydrocracking tail oil atomizing steam; r35 second shuttle valve iii; R35A second regenerant iii inlet;

g20 second regenerator, G21 charring air, G21A charring gas inlet, G22 second regeneration vertical pipe II, G22A second regenerant II outlet, G24 second regeneration vertical pipe I, G24A second regenerant I outlet, G25 second regenerator dilute phase, G27 charred flue gas, G27A second flue gas outlet and G28 fuel; g34 second regeneration standpipe III, G34A second regenerant III outlet;

s20 second stripping section, S21 second stripping section components;

d20 second settler;

a T10 first reaction system product heavy component separation tower, a T20 fractionating tower, an A1 heat exchanger and a B steam generator;

f3 water, F4 steam, F21 liquefied gas and dry gas products, F22 gasoline component, F23 light cycle oil component (or LCO component), and F24 tower bottom heavy component;

TIC temperature display control.

The specific implementation mode is as follows:

the technical solutions of the present invention are described below in the following embodiments and examples, but the scope of the present invention is not limited thereto.

The first implementation mode comprises the following steps:

in the method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material of the embodiment, the catalytic conversion device shown in fig. 1 is adopted, the first reaction regeneration system and the second reaction regeneration system are arranged, and the heavy petroleum hydrocarbon and the hydrocracking tail oil are used as raw materials, and in specific implementation, the heavy petroleum hydrocarbon raw material can be one or a mixture of vacuum wax oil, residual oil, coking wax oil, deasphalted oil, hydrogenation wax oil, hydrogenation residual oil, hydrogenation catalytic diesel oil, crude oil and condensate oil, and the boiling point is higher than 320 ℃; in the invention, hydrocracking tail oil is a technical term which is fixedly known in the field, the property of the hydrocracking tail oil is related to raw oil adopted in hydrocracking, and in the specific implementation, the BMCI value of the hydrocracking tail oil capable of performing catalytic conversion is less than or equal to 20;

the first reaction regeneration system is provided with a first reactor R10, a first settler D10, a first stripping section S10 and a first regenerator G10, wherein the first reactor R10 is arranged in parallel with the first regenerator G10; an outlet of the first reactor R10 is communicated with a first cyclone separator D11 of a gas-solid separation device in a first settler D10, a first stripping section S10 is arranged below the first settler D10, and a first stripping component S11 is arranged in the first stripping section S10; the lower part of the first stripping section S10 is communicated with a first regenerator G10 through a first standby riser R16A from a first standby agent inlet G12A, and a first standby slide valve R16 is arranged on the first standby riser R16A; in specific implementation, the first regenerator G10 adopts a fast fluidized bed and dense-phase fluidized bed regeneration mode of a coking tank, the first regenerator G10 is communicated with a first reactor regenerant inlet R15A of a first reactor R10 through a first regeneration riser G14 by a first regenerant outlet G14A, a first regeneration slide valve R15 is arranged on a first regeneration riser G14, a first regenerator cyclone separator G16 is arranged in a first regenerator dilute phase region G15 of the first regenerator G10, the first regenerator coked flue gas G17 is discharged from a first flue gas outlet G17A at the top of the first regenerator G10, and the catalyst regeneration gas G11 is introduced from a first regeneration gas inlet G11A at the bottom of the first regenerator G10; a heavy petroleum hydrocarbon inlet R12A is arranged at the lower part of the first reactor R10 to introduce the heavy petroleum hydrocarbon R12 and the raw material atomizing steam R13, and a catalyst pre-lift gas inlet R11A is arranged at the lower part of the first reactor R10 to introduce the catalyst pre-lift gas R11; the top of the first settler D10 is provided with a first reaction gas product outlet R14A;

the second reaction regeneration system is provided with a second reactor R20, a second settler D20, a second stripping section S20 and a second regenerator G20, the second reactor R20 and the second regenerator G20 are arranged in parallel, the outlet of the second reactor R20 is communicated with a gas-solid separation device (not shown in the figure) in the second settler D20, the second stripping section S20 is arranged below the second settler D20, and a second stripping component S21 is arranged in the second stripping section S20; the lower part of the second stripping section S20 is communicated with a second regenerator G20 through a second spent riser R26A and a second spent agent valve R26; in specific implementation, a gas-solid separation device (not shown in the figure) is arranged in a dilute phase zone G25 of the second regenerator G20, the burned flue gas G27 is discharged from a second flue gas outlet G27A at the upper part of the second regenerator G20, the burning air G21 is introduced from a burning gas inlet G21A at the bottom of the second regenerator G20, and a second spent agent from the second stripping section S20 firstly enters the second regenerator G20 from a second spent agent valve R26 at the lower part of the second regenerator for regeneration; in specific implementation, the second regenerator G20 adopts a two-section regeneration mode in series connection up and down, the second spent agent firstly enters a first section regeneration zone from a second spent agent valve R26, contacts and reacts with burnt air G21, flows upwards and enters a second section regeneration zone for continuous regeneration, fuel G28 is supplemented in the second section regeneration zone to realize heat supplementation of the regenerator, in specific operation implementation, the temperature and carbon content of the first section regeneration are controlled according to the amount of catalyst introduced into the first section regeneration zone and the amount of burnt air G21, the temperature and carbon content of the second section regeneration are controlled according to the amount of catalyst introduced into the second section regeneration zone and the amount of supplemented fuel G28, and the second regeneration agent II comes from the second section regeneration zone, and the second regeneration agent I comes from the second section regeneration zone or the first section regeneration zone. In the embodiment, the second regenerant I is from a first-stage regeneration zone and is used as a lower catalyst, the second regenerant II is from a second-stage regeneration zone and is used as an upper catalyst, the second reactor R20 is divided into an upper reaction zone and a lower reaction zone by the upper catalyst and a heat supply position, namely a second regenerant inlet IIR 22A, and the second reactor R20 is arranged in the form of an upper-lower subarea reactor with upper and lower catalyst circulation and twice heat supply and comprises a lower sub-high-temperature reaction zone R27 and an upper high-temperature reaction zone R28; wherein a second regenerant I inlet R25A at the lower part of the secondary high temperature reaction zone R27 is communicated with a second regenerant I outlet G24A of the second regenerator G20 through a second regeneration riser I24, a second regeneration slide valve I R25 is arranged on the second regeneration riser I24, a second regenerant II inlet R22A at the lower part of the high temperature reaction zone R28 is communicated with a second regenerant II outlet G22A of the second regenerator G20 through a second regeneration riser II G22, and a second regeneration slide valve II R22 is arranged on the second regeneration riser II G22; introducing supplementary steam R21 into the second high-temperature reaction zone above or below the second regenerant I inlet R25A at the lower part of the second high-temperature reaction zone R27, and introducing supplementary steam R23 into the high-temperature reaction zone above or below the second regenerant II inlet R22A at the lower part of the high-temperature reaction zone R28;

a material flow pipeline is arranged between the first reaction gas product outlet R14A and the bottom of the high-temperature reaction zone R28, a first reaction system product R14 can directly enter the high-temperature reaction zone R28 in a gas phase state through the material flow pipeline, a hydrocracking tail oil inlet is arranged at the bottom of the second reactor R20, namely the bottom of the second high-temperature reaction zone R27, the hydrocracking tail oil R32 sequentially enters the second high-temperature reaction zone R27 and the high-temperature reaction zone R28 to participate in the reaction in the second reactor R20, and the hydrocracking tail oil R32 is atomized by hydrocracking tail oil atomization steam R33; in specific implementation, the first reactor R10 and the second reactor R20 can adopt a riser, a single fluidized bed reactor or a composite reactor, in the embodiment, the first reactor R10 and the second reactor R20 adopt a riser form;

in the method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material according to the embodiment, heavy petroleum hydrocarbon R12 is firstly subjected to catalytic conversion in a first reaction regeneration system, and the reaction product is subjected to catalytic conversion in a gaseous form together with hydrocracking tail oil in a second reaction regeneration system, wherein the first reaction regeneration system is mainly used for decarburization, demetalization and catalytic conversion of heavy petroleum hydrocarbon raw material, and the second reaction regeneration system is used for cracking to prepare olefin; the first reaction regeneration system uses a first catalyst, and the second reaction regeneration system uses a second catalyst; in the specific implementation, the active component of the first catalyst is selected from one or a mixture of HY, USY, REY, REHY, REUSY and H-ZSM-5, and belongs to a catalyst with high activity or strong catalytic capability for the catalytic cracking of heavy raw oil; the active component of the second catalyst is selected from one or a mixture of Y-type zeolite, L-type zeolite, ZSM-5 zeolite, beta zeolite, aluminum phosphate zeolite and mordenite, or modified zeolite, and belongs to a catalyst with strong intermediate component or micromolecule cracking capability and high selectivity of low-carbon olefin. The specific process flow is as follows:

(1) the preheated heavy petroleum hydrocarbon R12 is firstly subjected to catalytic conversion in a first reaction regeneration system, enters a reaction zone R17 of a first reactor R10, and is subjected to catalytic cracking reaction mainly comprising heavy petroleum hydrocarbon macromolecules under the action of a first catalyst from a first regenerator G10, wherein the reaction temperature of a reactor outlet of the first reactor R10 is 490-600 ℃, the reaction time is 0.5-5.0 s, and the absolute pressure of the reaction pressure is 0.23-0.50 MPa; after the stream formed by the reaction in the first reactor R10 enters a first cyclone D11 in a first settler D10 to separate out the first catalyst, a first reaction system product R14 consisting of heavier components or larger molecules and intermediate components is formed; the first catalyst separated by the first settler D10 enters a first regenerator G10 for regeneration after being stripped in a first stripping section S10 for recycling;

(2) the first reaction system product R14 directly enters the high-temperature reaction zone R28 of the second reactor R20 in a gaseous form through a stream line;

the atomized hydrocracking tail oil R32 firstly enters the bottom of a secondary high-temperature reaction zone R27, and is subjected to secondary high-temperature reaction mainly comprising catalytic cracking of heavier components or larger molecules and intermediate components under the environment of a second catalyst I introduced from a second regenerator G20 through a second regeneration vertical pipe IG 24, the reaction temperature is 520-600 ℃, the reaction time is 0.1-5.0 s, the absolute reaction pressure is 0.20-0.40 MPa, the actual reaction temperature is controlled by the catalyst entering the secondary high-temperature reaction zone R27, and in the specific implementation, the temperature of the second catalyst I is 660-820 ℃, and the carbon content is lower than 0.15%; the product and the catalyst in the secondary high-temperature reaction zone R27 flow upwards to enter a high-temperature reaction zone R28, the high-temperature reaction of the combination of catalytic cracking and thermal cracking with increased temperature is carried out in the environment of a second catalyst II introduced from a second regenerator G20 through a second regeneration vertical pipe II G22, the conversion of the intermediate component to ethylene and propylene is realized, the reaction temperature is 550-750 ℃, the reaction time is 0.1-5.0 s, the absolute reaction pressure is 0.20-0.40 MPa, the actual reaction temperature is controlled by the catalyst entering the high-temperature reaction zone R28, and in the specific implementation, the temperature of the second catalyst II is 700-850 ℃, and the carbon content is lower than 0.5%; after a material flow formed by the reaction of the second reactor R20 enters a second settler D20 to separate out the catalyst, a second reaction system product R24 mainly containing olefin is obtained, namely a target product is sent out of the device and enters a subsequent process for treatment; the catalyst separated by the second precipitator D20 enters a second regenerator G20 for regeneration after being stripped by a second stripping section S20 and is recycled.

Example 1:

the device and the process are shown in figure 1, and the implementation parameters are as follows:

the reaction materials are normal pressure heavy oil and hydrocracking tail oil, and the hydrocracking tail oil is fed separately. Atmospheric heavy oil with density of 0.91, hydrogen content of 12.8 wt%, carbon residue of 3.8%, saturated hydrocarbon content of 61%, Ni less than 4.0ppm, and V less than 0.1 ppm; the density of hydrocracking tail oil is 0.82, and the BMCI value is 10.6; the hydrocracking tail oil accounts for 10% of the raw oil;

the preheating temperature of the heavy oil at normal pressure is 220 ℃; the hydrocracking tail oil temperature is 300 ℃;

first reactor reaction conditions: the reaction temperature (i.e. the reactor outlet reaction temperature) TIC-1 was 530 ℃ and the reaction time was 1.0s (sec); the temperature of the regenerant (namely the first catalyst) entering the regenerant inlet of the first reactor is 680 ℃, atomized steam is 4% of the normal pressure heavy oil, and catalyst pre-lifting steam is 2% of the normal pressure heavy oil; reaction pressure (first settler D10 pressure) 170KPa (gauge) (i.e. 0.27 MPa);

reaction conditions of the second reactor: the reaction pressure (second settler pressure) was 120kpa (gauge pressure) (i.e., 0.22 MPa);

reaction conditions of the secondary high temperature reaction zone R27: the temperature of a catalyst (second regenerant I) entering from an inlet of the second regenerant I is 730 ℃, the reaction temperature TIC-2 is 620 ℃, the reaction time is 0.4s, the proportion of supplemented steam is 4 percent (accounting for the mass ratio of the raw oil), and the proportion of steam in a reaction zone is 10 percent of the weight of the raw oil;

reaction conditions of the high temperature reaction zone R28: the temperature of a catalyst (second regenerant II) entering from an inlet of the second regenerant II is 730 ℃, the reaction temperature TIC-3 is 670 ℃, the reaction time is 1.5 seconds, the make-up steam is 14 percent of the oil mass of the raw material, the atomized steam of the hydrocracking tail oil is 3 percent of the hydrocracking tail oil, and the proportion of the total steam in the reaction zone to the raw material oil is 31 percent;

the implementation process is as follows:

atomizing atmospheric heavy oil steam, then feeding the atomized atmospheric heavy oil steam into a first reactor, and performing heavy oil catalytic cracking conversion under the heat provided by a regenerant and catalytic environment, wherein the heat is fed from a regenerant inlet of the first reactor, so that the cracking conversion from macromolecules to intermediate molecules is realized, an intermediate component raw material with the molecular weight of 80-200 is obtained as far as possible, and a raw material is provided for further conversion into olefin; after the reaction of the first reactor is finished, the product enters a settler to separate out the catalyst, the product of the first reaction system flows out of the first settler, and then directly enters a high-temperature reaction zone of a second reactor to continue to carry out the pyrolysis reaction of the residual heavy oil and the middle distillate of larger molecules;

after steam atomization of hydrocracking tail oil, the hydrocracking tail oil enters a second reactor at the bottom of a secondary high-temperature reaction zone and reacts in the secondary high-temperature reaction zone at the lower part of the second reactor; the second regenerant I from the second regenerator enters a secondary high-temperature reaction zone to realize the catalytic conversion of the hydrocracking tail oil; supplementing steam accounting for 4% of the raw oil in the secondary high-temperature reaction zone;

the gas material flow and the catalyst generated in the secondary reaction zone continuously flow upwards and enter the high-temperature reaction zone; the high-temperature catalyst from the regenerator, namely a second regenerant II, enters a second reactor, is conveyed upwards by gas from a secondary high-temperature reaction zone of the reactor to enter a high-temperature reaction zone, further provides heat for the high-temperature reaction zone, improves the reaction temperature in the high-temperature reaction zone, and reduces the activation energy level of components from C5 to C12 under the action of the catalyst, so that the catalytic conversion and thermal cracking mixed reaction of alkane, alkene and cycloalkane are realized, and the alkene is generated;

carrying out gas-solid separation on the reaction product material flow in the high-temperature reaction zone in a second precipitator, and enabling the product gas (a second reaction system product) from which the catalyst is separated to flow out of the second precipitator and enter a subsequent treatment system;

the high-temperature reaction zone further supplements steam, so that the steam amount in the high-temperature reaction zone reaches 31% of the atmospheric heavy oil amount;

the catalyst separated from the first settler enters a first regenerator for catalyst regeneration after being stripped; the catalyst separated in the second precipitator enters a second regenerator for catalyst regeneration after being stripped;

the second regenerator is provided with supplementary fuel oil G28 which is 1.5 percent of the normal pressure heavy oil and supplements heat for the reaction, thereby realizing the required regeneration temperature.

The regeneration of the catalyst, the gas-solid separation and the subsequent oil-gas treatment are common technologies and are not described in detail.

Catalyst used in the first reaction regeneration system (first catalyst): the rare earth modified Y-type molecular sieve is used as a main active component, and the main parameters are as follows: balancer activity 65%, abrasion index 2.0%, D, v (0.5) ═ 68 μm.

Catalyst used in the second reaction regeneration system (second catalyst): ZSM-5 is taken as a main active component, and the main parameters are as follows:

balancer activity 47%, abrasion index 1.0%, D, v (0.5) ═ 60 μm.

Example 1 the product distribution is shown in table 1:

table 1 example 1 product distribution

The second embodiment:

the method for producing olefins by catalytic conversion of a petroleum hydrocarbon feedstock according to the present embodiment employs a catalytic conversion apparatus shown in fig. 2, and includes a first reaction regeneration system and a second reaction regeneration system;

the second regenerator G20 adopts a two-stage regeneration mode which is connected in series up and down, when the concrete operation is implemented, the temperature and the carbon content of the first stage regeneration are controlled according to the amount of the catalyst and the amount of the coke-burning air G21 which are introduced into the first stage regeneration zone, and the temperature and the carbon content of the second stage regeneration are controlled according to the amount of the catalyst which is introduced into the second stage regeneration zone; a second reaction system product R24 led out from an outlet at the top of the second settler D20 enters a fractionating tower T20 after heat exchange and temperature reduction by a heat exchanger A1, and the second reaction system product R24 is separated into a liquefied gas and dry gas product F21, a gasoline component F22, a light cycle oil component F23 and a heavy component F24 at the bottom of the tower;

a material flow pipeline is arranged between the first reaction gas product outlet R14A and the bottom of the second reactor R20, and a first reaction system product heavy component separation tower T10 is arranged on the material flow pipeline; the first reaction system product R14 is separated into heavy components, namely the first reaction system product liquid heavy component R14L, through a first reaction system product heavy component separation tower T10 to form a first reaction system product light component R14G, the first reaction system product light component R14G firstly enters a heat exchanger A1 to exchange heat with a second reaction system product R24, and the heated first reaction system product light component R14G enters a second reaction regeneration system in a gas phase state; in the embodiment, the light component R14G of the first reaction system product sequentially enters a secondary high-temperature reaction zone R27 and a high-temperature reaction zone R28 to participate in the reaction in the second reactor R20, and the hydrocracking tail oil R32 directly enters a high-temperature reaction zone R28 for catalytic conversion; the other part of the device structure of this embodiment is the same as that of the first embodiment;

the specific implementation process of the embodiment is as follows:

(1) the preheated heavy petroleum hydrocarbon R12 is firstly catalytically converted in a first reaction regeneration system to form a first reaction system product R14; the first catalyst is separated, stripped and regenerated for recycling;

(2) the first reaction system product R14 is separated into a first reaction system product liquid heavy component R14L with the temperature of more than 500 ℃ through a first reaction system product heavy component separation tower T10 to form a first reaction system product light component R14G; the light component R14G of the first reaction system product enters a heat exchanger A1, is heated by a product R24 of a second reaction system, then enters a second reactor R20 in a gas phase state through a material flow pipeline to continue catalytic conversion, firstly enters a secondary high-temperature reaction zone R27 to carry out catalytic cracking reaction of residual heavy oil and middle distillate of larger molecules, namely secondary high-temperature reaction, and steam accounting for 8 percent of the heavy petroleum hydrocarbon raw material is supplemented in the secondary high-temperature reaction zone; the product and the catalyst in the secondary high-temperature reaction zone R27 flow upwards to enter a high-temperature reaction zone R28, and together with the atomized hydrocracking tail oil R32, the product and the catalyst in the secondary high-temperature reaction zone R28 are subjected to high-temperature reaction of catalytic conversion and thermal cracking mixing of alkane, alkene and cycloalkane with increased temperature in a high-temperature reaction zone R28 to generate alkene, the temperature of the catalyst (second regenerant I) entering from the inlet of the second regenerant I is 730 ℃, and the temperature of the catalyst (second regenerant II) entering from the inlet of the second regenerant II is 700 ℃; after a catalyst is separated from a material flow formed by the reaction of the second reactor R20, a second reaction system product R24 is obtained, namely a target product, the target product flows through a heat exchanger A1 to be cooled and enters a fractionating tower T20 to be separated into a liquefied gas and dry gas product F21, a gasoline component F22, a light cycle oil component F23 and a tower bottom heavy component F24; the separated catalyst is stripped and then enters a second regenerator G20 for regeneration and recycling.

Heat exchangers are well known to those skilled in the art and will not be described in detail.

The third embodiment is as follows:

the method for producing olefins by catalytic conversion of a petroleum hydrocarbon feedstock according to the present embodiment employs a catalytic converter shown in fig. 3, and includes a first reaction regeneration system and a second reaction regeneration system;

the second reaction regeneration system is provided with a second reactor R20, a second settler D20, a second stripping section S20, a second regenerator G20 and a third reactor R30; a stream line is provided between the first reaction gas product outlet R14A of the first precipitator D10 and the bottom of the second reactor R20;

the second reactor R20 is set into the form of upper and lower subarea reactors with upper and lower catalyst circulation and twice heat supply, and comprises a lower sub-high temperature reaction zone R27 and an upper high temperature reaction zone R28; introducing supplementary steam R21 of the secondary high-temperature reaction zone above a second regenerant I inlet R25A at the lower part of the secondary high-temperature reaction zone R27, and introducing supplementary steam R23 of the high-temperature reaction zone above a second regenerant II inlet R22A at the lower part of the high-temperature reaction zone R28;

a second reaction system product R24 led out from an outlet at the top of the second settler D20 enters a steam generator B, water F3 is heated into steam F4, and then enters a fractionating tower T20, and a second reaction system product R24 is separated into a liquefied gas product F21, a dry gas product F22, a light cycle oil product F23 and a bottom heavy component F24;

the third reactor R30 shares a second settler D20, a second stripping section S20 and a second regenerator G20 with the second reactor R20, and a second regenerant III inlet R35A at the lower part of the third reactor R30 communicates with a second regenerant III outlet G34A of the second regenerator G20 through a second regeneration riser III G34; a hydrocracking tail oil inlet (not shown in the figure) is arranged at the bottom of the third reactor R30, hydrocracking tail oil R32 is atomized by hydrocracking tail oil atomization steam R33 and then enters the third reactor R30 from the hydrocracking tail oil inlet, and third reactor steam R31 is introduced from the bottom of the third reactor R30;

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

one specific example parameter of this embodiment is as follows:

the reaction temperature of the second reactor is 660 ℃, the steam supplementing quantity of the secondary high-temperature reaction zone is determined according to the fact that the total quantity of steam in the second reactor is 35 percent of the oil quantity of the raw material, the reaction time is 1.5 seconds, and the temperature of a catalyst (namely a second regenerant I) from the second regenerator is 730 ℃; after being atomized by steam, the hydrocracking tail oil enters a third reactor, and is subjected to catalytic cracking and thermal cracking mixed reaction in an independent lifting pipe; the reaction temperature was 670 ℃ and the reaction time was 1.4 seconds. The catalyst (i.e. the second regenerant III) from the second regenerator enters a third reactor; the third reactor is supplemented with steam which is provided by 30 percent of hydrocracking tail oil, and a second regenerant III is 730 ℃;

the product of the second reaction system is firstly put into a steam generator to be cooled to 560 ℃, the water inlet temperature is 220 ℃, the steam pressure is 11MPa, and the temperature is the saturation temperature. The steam generator is a common device and is well known to the skilled person.

Claims

1. A method for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material, heavy petroleum hydrocarbon (R12) and hydrocracking tail oil (R32) are used as raw materials, catalytic conversion is carried out in a first reaction regeneration system and a second reaction regeneration system to prepare olefin, the first reaction regeneration system uses a first catalyst, and the second reaction regeneration system uses a second catalyst; the method is characterized in that: the method comprises the following steps:

(1) the method comprises the steps that heavy petroleum hydrocarbon (R12) is firstly subjected to catalytic conversion in a first reaction regeneration system, enters a first reactor (R10) and is subjected to catalytic cracking reaction under the environment of a first catalyst from a first regenerator (G10), the reaction temperature of the reactor outlet of the first reactor (R10) is 490-600 ℃, the reaction time is 0.5-5.0 s, and the absolute pressure of the reaction pressure is 0.23-0.50 MPa; after the stream formed by the reaction in the first reactor (R10) enters a first settler (D10) to separate out the first catalyst, a first reaction system product (R14) is formed; the first catalyst separated by the first settler (D10) enters a first regenerator (G10) for regeneration after being stripped in a first stripping section (S10) and is recycled;

(2) the first reaction system product (R14) or the light component (R14G) of the first reaction system product after heavy components are separated enters a second reaction regeneration system together with the hydrocracking tail oil (R32) for catalytic conversion;

the first reaction system product (R14) or the light component (R14G) of the first reaction system product and the hydrocracking tail oil (R32) enter a second reactor (R20) of an upper partition and a lower partition of a second reaction regeneration system to carry out the following catalytic conversion:

or the first reaction system product (R14) or the first reaction system product light component (R14G) firstly enters the bottom of a second high-temperature reaction zone (R27) of a second reactor (R20), the second high-temperature reaction is carried out under the environment of a second catalyst I introduced from a second regenerator (G20) through a second regeneration vertical pipe I (G24), the reaction temperature is 520-600 ℃, the reaction time is 0.1-5.0 s, the absolute pressure of the reaction pressure is 0.20-0.40 MPa, the actual reaction temperature is controlled by the catalyst amount entering the second high-temperature reaction zone (R27), the product and the catalyst in the second high-temperature reaction zone (R27) flow upwards to enter the high-temperature reaction zone (R28) of the second reactor (R20) and are mixed with hydrocracking tail oil (R32) directly entering the high-temperature reaction zone (R28), and the high-temperature reaction is carried out under the environment that the temperature is increased by the second catalyst II introduced from the second regenerator (G20) through a second regeneration vertical pipe II (G22), the reaction temperature is 550-750 ℃, the reaction time is 0.1-5.0 s, the absolute pressure of the reaction is 0.20-0.40 MPa, and the actual reaction temperature is controlled by the amount of the catalyst entering the high-temperature reaction zone (R28); or the first reaction system product (R14) or the light component (R14G) of the first reaction system product directly reacts in the high-temperature reaction zone (R28), the hydrocracking tail oil (R32) firstly enters the second high-temperature reaction zone (R27) to carry out second high-temperature reaction, then flows upwards with the catalyst to enter the high-temperature reaction zone (R28), and is mixed with the first reaction system product (R14) or the light component (R14G) of the first reaction system product directly entering the high-temperature reaction zone (R28) to carry out high-temperature reaction; or the first reaction system product (R14) or the light component (R14G) of the first reaction system product and the hydrocracking tail oil (R32) directly enter a secondary high-temperature reaction zone (R27) to carry out secondary high-temperature reaction, and then the second reaction system product and the catalyst flow upwards to enter the high-temperature reaction zone (R28) to continue to react; after the material flow formed by the reaction of the second reactor (R20) enters a second settler (D20) to separate the catalyst, a second reaction system product (R24) is obtained; the catalyst separated by the second settler (D20) enters a second regenerator (G20) for regeneration after being stripped in a second stripping section (S20) and is recycled;

or the first reaction system product (R14) or the first reaction system product light component (R14G) enters a second reactor (R20) of an upper and lower subarea of a second reaction regeneration system, and sequentially reacts in a secondary high-temperature reaction zone (R27) and a high-temperature reaction zone (R28), and meanwhile, hydrocracking tail oil (R32) reacts in a third reactor (R30) which is independent of the second reaction regeneration system; the first reaction system product (R14) or the light component (R14G) of the first reaction system product enters the bottom of the second high temperature reaction zone (R27) first, carrying out a second high temperature reaction in the presence of a second catalyst I introduced from a second regenerator (G20) via a second regeneration riser I (G24), the product and catalyst of the second high temperature reaction zone (R27) flowing upwardly into the high temperature reaction zone (R28), the high-temperature reaction with the temperature rise is carried out under the environment of a second catalyst II introduced from a second regenerator (G20) through a second regeneration riser II (G22), the hydrocracking tail oil (R32) enters the lower part of a third reactor (R30), the high-temperature reaction is carried out in the environment of a second catalyst III introduced from a second regenerator (G20) through a second regeneration riser III (G34), the third reactor (R30) has the reaction temperature of 550-720 ℃, the reaction time of 0.5-5.0 s and the absolute pressure of 0.2-0.4 MPa; after the material flow formed by the reaction of the second reactor (R20) and the third reactor (R30) enters a second settler (D20) to separate the catalyst, a second reaction system product (R24) is obtained; the catalyst separated by the second precipitator (D20) enters a second regenerator (G20) for regeneration after being stripped in a second stripping section (S20) and is recycled.

2. A process for the catalytic conversion of a petroleum hydrocarbon feedstock to olefins as defined in claim 1, wherein: the first reaction system product (R14) is separated into heavy components through a separation tower or a fractionating tower to form a first reaction system product light component (R14G), and the first reaction system product light component (R14G) enters a second reaction regeneration system in a gas phase state.

3. A process for the catalytic conversion of a petroleum hydrocarbon feedstock to olefins as defined in claim 1, wherein: the heavy petroleum hydrocarbon (R12) is one or a mixture of vacuum wax oil, residual oil, coking wax oil, deasphalted oil, hydrogenated wax oil, hydrogenated residual oil, hydrogenated catalytic diesel oil, crude oil and condensate oil, and the boiling point is higher than 320 ℃.

4. A process for the catalytic conversion of a petroleum hydrocarbon feedstock to olefins as defined in claim 1, wherein: the active component of the first catalyst is selected from one or a mixture of HY, USY, REY, REHY, REUSY and H-ZSM-5; the active component of the second catalyst is selected from Y-type zeolite, L-type zeolite, ZSM-5 zeolite, beta zeolite, aluminum phosphate zeolite, mordenite, or one or a mixture of modified zeolites.

5. A process for the catalytic conversion of a petroleum hydrocarbon feedstock to olefins as defined in claim 1, wherein: the temperature of the second catalyst I introduced into the secondary high-temperature reaction zone (R27) through the second regeneration vertical pipe I (G24) is 660-820 ℃, and the temperature of the second catalyst II introduced into the high-temperature reaction zone (R28) through the second regeneration vertical pipe II (G22) is 700-850 ℃.

6. A process for the catalytic conversion of a petroleum hydrocarbon feedstock to olefins as defined in claim 1, wherein: the carbon content of the second catalyst I introduced into the secondary high-temperature reaction zone (R27) through the second regeneration vertical pipe I (G24) is lower than 0.15%, and the carbon content of the second catalyst II introduced into the high-temperature reaction zone (R28) through the second regeneration vertical pipe II (G22) is lower than 0.5%.

7. A process for the catalytic conversion of a petroleum hydrocarbon feedstock to olefins as defined in claim 1, wherein: the second regenerator (G20) of the second reaction regeneration system is replenished with fuel (G28).

8. A process for the catalytic conversion of a petroleum hydrocarbon feedstock to olefins as defined in claim 1, wherein: when the light component (R14G) of the product of the first reaction system enters the second reaction regeneration system, the light component (R14G) of the product of the first reaction system exchanges heat with the product (R24) of the second reaction system, and the heated light component (R14G) of the product of the first reaction system enters the second reaction regeneration system for reaction.

9. A device for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material is provided with a first reaction regeneration system and a second reaction regeneration system, wherein the first reaction regeneration system is provided with a first reactor (R10), a first settler (D10), a first stripping section (S10) and a first regenerator (G10), and a heavy petroleum hydrocarbon inlet (R12A) is arranged at the lower part of the first reactor (R10); the second reaction regeneration system is provided with a second reactor (R20), a second settler (D20), a second stripping section (S20) and a second regenerator (G20); a stream line is provided between the first reaction gas product outlet (R14A) of the first settler (D10) and the second reactor (R20), or a stream line is provided between the first reaction gas product outlet (R14A) and the second reactor (R20), on which stream line a separation column or a fractionation column is simultaneously provided; the first reactor (R10) and the second reactor (R20) are selected from a riser, a fluidized bed single or composite reactor; the method is characterized in that:

the second reactor (R20) comprising a lower, secondary high temperature reaction zone (R27) and an upper high temperature reaction zone (R28); a second regenerant I inlet (R25A) at the lower part of the secondary high temperature reaction zone (R27) is communicated with a second regenerant I outlet (G24A) of the second regenerator (G20) through a second regeneration riser I (G24), and a second regenerant II inlet (R22A) at the lower part of the high temperature reaction zone (R28) is communicated with a second regenerant II outlet (G22A) of the second regenerator (G20) through a second regeneration riser II (G22);

a hydrocracking tail oil inlet is arranged at the bottom of the secondary high-temperature reaction zone (R27), and the stream line is arranged between a first reaction gas product outlet (R14A) and the bottom of the high-temperature reaction zone (R28); or a hydrocracking tail oil inlet is arranged at the bottom of the high-temperature reaction zone (R28), and the stream line is arranged between the first reaction gas product outlet (R14A) and the bottom of the secondary high-temperature reaction zone (R27).

10. A device for preparing olefin by catalytic conversion of petroleum hydrocarbon raw material is provided with a first reaction regeneration system and a second reaction regeneration system, wherein the first reaction regeneration system is provided with a first reactor (R10), a first settler (D10), a first stripping section (S10) and a first regenerator (G10), and a heavy petroleum hydrocarbon inlet (R12A) is arranged at the lower part of the first reactor (R10); the second reaction regeneration system is provided with a second reactor (R20), a second settler (D20), a second stripping section (S20), a second regenerator (G20) and a third reactor (R30); -a stream line is provided between the first reaction gas product outlet (R14A) of the first settler (D10) and the bottom of the second reactor (R20), or a stream line is provided between the first reaction gas product outlet (R14A) and the bottom of the second reactor (R20), while a separation or fractionation column is provided on the stream line; the first reactor (R10), the second reactor (R20) and the third reactor (R30) are selected from the group consisting of riser, fluidized bed single or multiple reactor; the method is characterized in that:

the second reactor (R20) comprising a lower, secondary high temperature reaction zone (R27) and an upper high temperature reaction zone (R28); a second regenerant I inlet (R25A) at the lower part of the secondary high temperature reaction zone (R27) is communicated with a second regenerant I outlet (G24A) of the second regenerator (G20) through a second regeneration riser I (G24), and a second regenerant II inlet (R22A) at the lower part of the high temperature reaction zone (R28) is communicated with a second regenerant II outlet (G22A) of the second regenerator (G20) through a second regeneration riser II (G22); the third reactor (R30) shares a second settler (D20), a second stripping section (S20) and a second regenerator (G20) with the second reactor (R20), and a second regenerant III inlet (R35A) at the lower part of the third reactor (R30) is communicated with a second regenerant III outlet (G34A) of the second regenerator (G20) through a second regeneration riser III (G34); a hydrocracking tail oil inlet is arranged at the lower part of the third reactor (R30).