阅读说明：本技术 烃油催化转化的方法 (Method for catalytic conversion of hydrocarbon oil ) 是由 白风宇 唐津莲 陈骞 袁起民 于 2020-05-29 设计创作，主要内容包括：本发明涉及在不存在氢的条件下烃油的催化转化的方法领域,公开了一种烃油催化转化的方法,该方法包括：(1)将加氢催化柴油原料与催化剂在第一提升管反应器中进行催化裂化反应,得到反应油气I和带炭催化剂；(2)将所述带炭催化剂经过或者不经过再生后引入至第二提升管反应器中,以与其中的汽油馏分和烷基转移剂接触并进行烷基转移反应,得到反应油气II和待生催化剂。本发明的方法使得,其一,加氢催化柴油消减效果明显,可达原料处理量的70％以上；其二,得到的反应油气II中芳烃含量升高；其三,能够在保持催化产物的产品分布和汽油组成与重量总体变化不大的前提下,增产高价值的芳烃产品,尤其大幅提高二甲苯收率。(The invention relates to the field of a method for catalytic conversion of hydrocarbon oil in the absence of hydrogen, and discloses a method for catalytic conversion of hydrocarbon oil, which comprises the following steps: (1) carrying out catalytic cracking reaction on a hydrogenated catalytic diesel raw material and a catalyst in a first riser reactor to obtain reaction oil gas I and a catalyst with carbon; (2) and introducing the carbon-carrying catalyst into a second riser reactor after or without regeneration so as to contact with the gasoline fraction and the transalkylation agent in the second riser reactor and carry out transalkylation reaction to obtain reaction oil gas II and a spent catalyst. The method of the invention has the advantages that firstly, the diesel oil reduction effect of the hydrogenation catalyst is obvious, and the diesel oil reduction effect can reach more than 70% of the raw material treatment capacity; secondly, the content of aromatic hydrocarbon in the obtained reaction oil gas II is increased; thirdly, the yield of high-value aromatic hydrocarbon products can be increased on the premise of keeping the product distribution of catalytic products and little overall change of gasoline composition and weight, and particularly the yield of dimethylbenzene is greatly increased.)

1. A process for the catalytic conversion of a hydrocarbon oil, the process comprising:

(1) carrying out catalytic cracking reaction on a hydrogenated catalytic diesel raw material and a catalyst in a first riser reactor to obtain reaction oil gas I and a catalyst with carbon;

(2) and introducing the carbon-carrying catalyst into a second riser reactor after or without regeneration so as to contact with the gasoline fraction and the transalkylation agent in the second riser reactor and carry out transalkylation reaction to obtain reaction oil gas II and a spent catalyst.

2. The process of claim 1, wherein the gasoline fraction is the same or different from the feed location of the transalkylation agent;

preferably, said gasoline fraction differs from the feed position of said transalkylation agent and the feed position of said gasoline fraction is upstream of the feed position of said transalkylation agent in terms of the stream direction;

preferably, the feed positions of said gasoline fraction and said transalkylation agent are controlled so that the time difference between said gasoline fraction and the feed of said transalkylation agent is 0.1 to 2 s.

3. The method according to claim 1 or 2, wherein the method further comprises: introducing the spent catalyst obtained in the step (2) into a regenerator I for regeneration, and introducing the obtained regenerated catalyst I into the first riser reactor and the second riser reactor to circularly participate in reaction;

preferably, the carbon content in the regenerated catalyst I is from 0.01 to 0.05% by weight.

4. A method according to any one of claims 1-3, wherein the method comprises: introducing the carbon-carrying catalyst obtained in the step (1) into a regenerator II for regeneration, and then introducing the carbon-carrying catalyst into the second riser reactor to participate in the transalkylation reaction.

5. The process according to claim 4, wherein the carbon content in the regenerated catalyst II introduced into the second riser reactor is from 0.01 to 0.1% by weight.

6. The process according to claim 4 or 5, wherein the carbon content in the coked catalyst obtained in step (1) is from 0.5 to 2% by weight, more preferably from 1 to 1.5% by weight.

7. A method according to any one of claims 1-3, wherein the method comprises: directly introducing the coked catalyst obtained in the step (1) into the second riser reactor without regeneration to participate in the transalkylation reaction;

preferably, the carbon content in the coked catalyst obtained in step (1) is from 0.5 to 2 wt%, more preferably from 1 to 1.5 wt%.

8. The process according to any one of claims 1 to 7, wherein the weight ratio of the amount of said transalkylation agent to said gasoline fraction is (0.015-0.5) to 1;

preferably, the transalkylation agent is benzene and/or toluene.

9. The process according to any one of claims 1 to 8, wherein the conditions of the catalytic cracking reaction are such that: the reaction temperature is 450-650 ℃, the reaction pressure is 100-450KPa, the reaction time is 0.1-30s, the weight ratio of the catalyst to the hydrogenation catalyst diesel raw material is (2-20):1, and the weight ratio of the water vapor to the hydrogenation catalyst diesel raw material is (0.01-0.5): 1;

preferably, the conditions of the catalytic cracking reaction satisfy: the reaction temperature is 500-650 ℃, the reaction pressure is 100-300KPa, the reaction time is 0.1-10s, the weight ratio of the catalyst to the hydrogenation catalyst diesel oil raw material is (3-10):1, and the weight ratio of the water vapor to the hydrogenation catalyst diesel oil raw material is (0.02-0.3): 1.

10. The process of any one of claims 1-9, wherein the transalkylation reaction satisfies the following conditions: the reaction temperature is 400-560 ℃, the reaction pressure is 140-600KPa, the reaction time is 0.5-30s, the weight ratio of the catalyst to the gasoline fraction is (6-20):1, and the weight ratio of the steam to the gasoline fraction is (0.01-0.5): 1;

preferably, the transalkylation reaction satisfies the following conditions: the reaction temperature is 460-500 ℃, the reaction pressure is 140-300KPa, the reaction time is 2-10s, the weight ratio of the catalyst to the gasoline fraction is (6-10):1, and the weight ratio of the steam to the gasoline fraction is (0.02-0.5): 1.

11. The process of any of claims 1-10, wherein the reaction temperature of the transalkylation reaction is lower than the reaction temperature of the catalytic cracking reaction.

12. The process according to any one of claims 1-11, wherein the hydrocatalytic diesel feedstock meets the following conditions: the density is less than or equal to 0.95g/cm³And/or the hydrogen content is more than or equal to 10 wt%;

preferably, the hydrocatalytic diesel feedstock satisfies the following conditions: the density is less than or equal to 0.92g/cm³And/or a hydrogen content of not less than 12% by weight.

13. The process as claimed in any one of claims 1 to 12, wherein the gasoline fraction has an initial boiling point of 60 to 95 ℃ and an end point of 180-205 ℃.

Technical Field

The invention relates to the technical field of catalytic conversion methods of hydrocarbon oil under the condition of no hydrogen, in particular to a catalytic conversion method of hydrocarbon oil.

Background

With the growth of national economy and the influence of factors such as road traffic electrification process, the demand of diesel oil in the domestic product oil market is reduced in recent years, and finding out low-quality diesel oil increasingly becomes one of the first problems to be considered by oil refining enterprises. Meanwhile, the demand of the domestic market for aromatic hydrocarbon products is rapidly increased, the conversion is carried out in the chemical industry direction, and the yield increase of high-value aromatic hydrocarbon products represented by Paraxylene (PX) becomes a future target of the development of the catalytic cracking technology. The domestic paraxylene supply still cannot meet domestic needs for a long time in the future. It is estimated that 1075 million tons of p-xylene are still imported domestically in 2020. The annual gap of the supply and demand of paraxylene in domestic markets is still more than 740 million tons in 2020-2025. In recent years, the increase of the production of aromatic hydrocarbon products represented by paraxylene in catalytic cracking of a main secondary processing unit of an oil refining enterprise has become a key technology concerned by technical personnel in the same industry.

Catalytic cracking is one of the important technical means for heavy oil conversion, and the contribution of domestic refinery catalytic diesel to the product diesel is more than 20%. Therefore, the optimization of the structure and operation of the catalytic cracking unit is one of the main methods for adjusting the product structure and reducing the factory pressure of diesel oil.

Aiming at new requirements of market product structure of finished oil, clean index of gasoline and the like, the technology for catalytic conversion of hydrocarbon oil by adopting double lifting pipes is developed rapidly. Generally, catalytic cracking of heavy hydrocarbon oils is carried out on the main riser; gasoline upgrading and conversion or the recycling of various diesel fractions is carried out on another riser.

CN1069054A discloses a flexible and multi-effect hydrocarbon catalytic cracking method, wherein the first riser in the prior art is used for processing light gasoline fraction hydrocarbon oil such as catalytic crude gasoline, coker gasoline and reformed raffinate oil, and simultaneously passivating metal pollutants on a catalyst; the second riser processes heavy hydrocarbon oil. The method can increase the yield of C2-C4 olefin and passivate metal pollutants on the regenerated catalyst. However, the overall gasoline yield is considerably affected by the re-cracking reactions involved in the individual gasoline fractions in the riser reactor.

CN1458227A discloses a method and a device for reducing the olefin content in catalytically cracked gasoline, in the prior art, a secondary condensation cooling system is established on an original conventional condensation cooling system of a fractionating tower, and is used for separating light fractions of crude gasoline and carrying out olefin reduction modification on the light fractions in an auxiliary modification and lifting device, so as to meet the environmental protection requirements of olefin reduction and the like. However, this process involves two different catalyst systems and is relatively complex to operate; because of carrying on the remilling modification to some crude gasolines, the gasoline yield is influenced correspondingly; the octane number of the gasoline is influenced to a certain extent because the olefin content in the product gasoline is reduced without corresponding octane number recovery measures.

In the prior art, the light hydrocarbon oil of the gasoline fraction is recycled and modified in an auxiliary (second) lifting pipe, which influences the gasoline yield of a catalytic device to a certain extent; these techniques contribute little to the production of aromatics. The use of dual riser technology for reducing diesel load while increasing the production of high quality aromatics has been reported. In addition, how to increase the yield of high-quality aromatic hydrocarbon products while reducing the yield of catalytic diesel oil has become one of the key issues of concern to those skilled in the art.

Disclosure of Invention

The invention aims to solve the problems that the recycle and modification methods of light hydrocarbon oil in the prior art can affect the yield of catalytic gasoline and increase the yield of aromatic hydrocarbon products, and provides a method for catalytic conversion of hydrocarbon oil, which can increase the yield of high-value aromatic hydrocarbon products such as xylene.

In order to achieve the above object, the present invention provides a method for catalytic conversion of a hydrocarbon oil, comprising:

(1) carrying out catalytic cracking reaction on a hydrogenated catalytic diesel raw material and a catalyst in a first riser reactor to obtain reaction oil gas I and a catalyst with carbon;

(2) and introducing the carbon-carrying catalyst into a second riser reactor after or without regeneration so as to contact with the gasoline fraction and the transalkylation agent in the second riser reactor and carry out transalkylation reaction to obtain reaction oil gas II and a spent catalyst.

According to the method for catalytic conversion of the hydrocarbon oil, the hydrocatalytic diesel raw material is subjected to catalytic cracking reaction and transalkylation reaction in sequence, and the catalytic cracking reaction and the transalkylation reaction are carried out in a subarea manner, so that firstly, the reduction effect of the hydrocatalytic diesel is obvious, the conversion rate of the hydrocatalytic diesel is high, and the conversion rate can reach more than 70% of the treatment capacity of the raw material; secondly, the content of aromatic hydrocarbon in the obtained reaction oil gas II is increased, and the octane number (RON) is increased by 0.2-2 units; thirdly, the yield of high-value aromatic hydrocarbon products can be increased on the premise of keeping the product distribution of catalytic products and little overall change of gasoline composition and weight, and particularly the yield of dimethylbenzene is greatly increased; and fourthly, because the two riser reactors are adopted for the zone reaction, the two riser reactors can be mutually independently controlled, so the operation is more flexible, the reaction parameters in the two riser reactors can be respectively adjusted according to actual requirements, the catalytic cracking reaction and the transalkylation reaction are respectively optimized and guided in an oriented mode, and the elasticity of the product structure is larger.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 is a schematic diagram of a reaction system used in a preferred embodiment of the present invention.

FIG. 2 is a schematic view of a reaction system used in another preferred embodiment provided by the present invention.

Description of the reference numerals

1 a-feed 2 a-first lifting steam 3 a-first riser reactor

4 a-first settler 5 a-first stripper 6 a-reaction oil gas I

7 a-first stand pipe to be regenerated 8 a-regenerator 9 a-regenerator main wind

10 a-settling cyclone separator 11 a-regeneration flue gas 12 a-gasoline fraction

13 a-second lift steam 14 a-transalkylation agent 15 a-second riser reactor

16 a-second settler 17 a-second stripper 18 a-reaction oil gas II

19 a-second inclined tube to be grown

1 b-feed 2 b-first lifting steam 3 b-first riser reactor

4 b-quick separation equipment 5 b-reaction oil gas I6 b-alkyl transfer agent

7 b-second lifting steam 8 b-second lifting pipe reactor 9 b-second settler

10 b-stripper 11 b-reaction oil gas II 12 b-spent riser

13 b-regenerator 14 b-regenerator main air 15 b-cyclone separator

16 b-regeneration flue gas 17 b-external heat exchanger 18 b-gasoline fraction

Detailed Description

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

As previously mentioned, the present invention provides a process for the catalytic conversion of a hydrocarbon oil, which process comprises:

(1) carrying out catalytic cracking reaction on a hydrogenated catalytic diesel raw material and a catalyst in a first riser reactor to obtain reaction oil gas I and a catalyst with carbon;

(2) and introducing the carbon-carrying catalyst into a second riser reactor after or without regeneration so as to contact with the gasoline fraction and the transalkylation agent in the second riser reactor and carry out transalkylation reaction to obtain reaction oil gas II and a spent catalyst.

According to the invention, in the catalytic cracking reaction process, the ring opening cracking reaction of naphthenic rings in the diesel oil raw material is mainly catalyzed by hydrogenation, and the obtained reaction oil gas I contains a large amount of multi-methyl monocyclic aromatic hydrocarbon; in the process of the transalkylation reaction, the transalkylation reaction between the multi-methyl monocyclic aromatic hydrocarbon and the methyl-deficient transalkylation agent is mainly generated, so that high-value aromatic hydrocarbon products such as xylene with middle carbon number (C8) and the like are generated to the maximum extent.

In the invention, the spent catalyst is stripped by a stripper after the reaction is finished, and the catalyst with carbon is the spent catalyst with coke after the reaction.

Preferably, the gasoline fraction is fed at the same or different location as the transalkylation agent. In the present invention, the feeding position refers to the relative height of the feeding.

In a preferred embodiment of the present invention, the gasoline fraction is fed at a position different from the feed position of the transalkylation agent, and the feed position of the gasoline fraction is upstream of the feed position of the transalkylation agent in terms of the flow direction.

Preferably, the feed positions of said gasoline fraction and said transalkylation agent are controlled so that the time difference between said gasoline fraction and the feed of said transalkylation agent is 0.1 to 2 s. By adopting the preferred technical scheme, the yield of the gasoline can be improved, and the yield of the dimethylbenzene, especially the p-dimethylbenzene, can be improved.

In a preferred embodiment of the present invention, the method further comprises: introducing the spent catalyst obtained in the step (2) into a regenerator I for regeneration, and introducing the obtained regenerated catalyst I into the first riser reactor and the second riser reactor to circularly participate in the reaction.

Preferably, the carbon content in the regenerated catalyst I is from 0.01 to 0.05% by weight.

In a preferred embodiment of the invention, the method comprises: introducing the carbon-carrying catalyst obtained in the step (1) into a regenerator II for regeneration, and then introducing the carbon-carrying catalyst into the second riser reactor to participate in the transalkylation reaction. In the present invention, the regenerator II may be the same as or different from the regenerator I, and is preferably the same.

Preferably, the carbon content in the regenerated catalyst II introduced into the second riser reactor is 0.01 to 0.1 wt%. In the present invention, the carbon content in the regenerated catalyst II refers to the carbon content before the regenerated catalyst II participates in the transalkylation reaction. Preferably, in this embodiment, the carbon content in the coked catalyst obtained in step (1) is from 0.5 to 2 wt.%, more preferably from 1 to 1.5 wt.%.

In another preferred embodiment of the present invention, the method comprises: introducing the coked catalyst obtained in the step (1) directly into the second riser reactor without regeneration to participate in the transalkylation reaction. Preferably, in this embodiment, the carbon content in the coked catalyst obtained in step (1) is from 0.5 to 2 wt.%, more preferably from 1 to 1.5 wt.%.

In the present invention, it is preferable that the amount weight ratio of the transalkylation agent to the gasoline fraction is (0.015-0.5): 1.

The invention has wider selectable range of the transalkylation agent; preferably, the transalkylation agent is benzene and/or toluene.

Preferably, the catalytic cracking reaction conditions satisfy: the reaction temperature is 450-650 ℃, the reaction pressure is 100-450KPa, the reaction time is 0.1-30s, the weight ratio of the catalyst to the hydrogenation catalyst diesel raw material is (2-20):1, and the weight ratio of the water vapor to the hydrogenation catalyst diesel raw material is (0.01-0.5): 1. In the present invention, the steam is the first lifting steam, and the hydrocatalytic diesel fuel raw material is introduced into the first lifting reactor under the action of the first lifting steam.

More preferably, the conditions of the catalytic cracking reaction satisfy: the reaction temperature is 500-650 ℃, the reaction pressure is 100-300KPa, the reaction time is 0.1-10s, the weight ratio of the catalyst to the hydrogenation catalyst diesel oil raw material is (3-10):1, and the weight ratio of the water vapor to the hydrogenation catalyst diesel oil raw material is (0.02-0.3): 1.

In the present invention, the lifting steam is a pre-lifting medium well known to those skilled in the art, and the lifting steam acts to accelerate the catalyst to rise, so as to form a plug flow of the catalyst with uniform density at the bottom of the riser reactor. The amount of the lifting steam is known to those skilled in the art, and generally, the amount of the lifting steam is 1 to 30% by weight, preferably 2 to 15% by weight, based on the total amount of the hydrocarbon oil.

Preferably, the transalkylation reaction satisfies the following conditions: the reaction temperature is 400-560 ℃, the reaction pressure is 140-600KPa, the reaction time is 0.5-30s, the weight ratio of the catalyst to the gasoline fraction is (6-20):1, and the weight ratio of the steam to the gasoline fraction is (0.01-0.5): 1. In the present invention, the steam refers to the second lifting steam, and the gasoline fraction is introduced into the second lifting reactor under the action of the second lifting steam; the catalyst herein may be a fresh catalyst, which means an unreacted catalyst, or a regenerated catalyst obtained by regenerating the carbon-containing catalyst obtained in step (1), preferably a regenerated catalyst.

More preferably, the transalkylation reaction satisfies the following conditions: the reaction temperature is 500-560 ℃, the reaction pressure is 140-300KPa, the reaction time is 2-10s, the weight ratio of the catalyst to the gasoline fraction is (6-10):1, and the weight ratio of the steam to the gasoline fraction is (0.02-0.5): 1.

According to the present invention, preferably, the reaction temperature of the transalkylation reaction is lower than the reaction temperature of the catalytic cracking reaction. By adopting the preferred scheme, the yield of the gasoline can be improved, and the yield of the dimethylbenzene, particularly the p-dimethylbenzene, can be improved.

In the invention, the hydrogenated catalytic diesel oil raw material is not limited and can be catalytic diesel oil produced by any existing catalytic cracking unit; preferably, the hydrocatalytic diesel feedstock satisfies the following conditions: the density is less than or equal to 0.95g/cm³And/or a hydrogen content of not less than 10% by weight.

More preferably, the hydrocatalytic diesel feedstock meets the following conditions: the density is less than or equal to 0.92g/cm³And/or a hydrogen content of not less than 12% by weight.

According to the invention, the gasoline fraction in the step (2) can be obtained by separating from the reaction oil gas I obtained in the step (1), and can also be gasoline fractions in any other cases; preferably separated from the reaction oil gas I obtained in the step (1). Preferably, the initial boiling point of the gasoline fraction is 60-95 ℃ and the final boiling point is 180-205 ℃.

In the invention, the step (1) may further include performing conventional separation on a reaction product obtained after the catalytic cracking reaction to obtain the reaction oil gas I and the carbon-containing catalyst.

In the invention, the reaction oil gas I obtained in the step (1) can be further processed according to the conventional method in the field, for example, the reaction oil gas I can enter a subsequent separation system to separate products such as liquefied gas, gasoline, diesel oil and the like.

According to the present invention, step (2) may further comprise conventional treatments of settling and stripping the coked catalyst before the regeneration is performed.

According to the invention, the catalyst is preferably an acidic catalytic cracking catalyst with or without a molecular sieve. The molecular sieve is preferably at least one of Y or HY type zeolite containing or not containing rare earth, ultrastable Y type zeolite containing or not containing rare earth, ZSM-5 series zeolite or high-silicon zeolite, beta zeolite and ferrierite with five-membered ring structure, and the catalyst is preferably an acidic catalytic cracking catalyst containing no molecular sieve, and is more preferably an amorphous silicon-aluminum catalyst.

According to a particularly preferred embodiment of the present invention, the method for catalytic conversion of hydrocarbon oil comprises:

(1) carrying out catalytic cracking reaction on a hydrogenated catalytic diesel raw material and a catalyst in a first riser reactor to obtain reaction oil gas I and a catalyst with carbon;

(2) introducing the catalyst with carbon into a regenerator II for regeneration, and then introducing the catalyst into a second riser reactor to contact with gasoline fraction and a transalkylation agent in the catalyst and perform transalkylation reaction to obtain reaction oil gas II and a spent catalyst;

introducing the spent catalyst obtained in the step (2) into a regenerator I for regeneration, and introducing the obtained regenerated catalyst I into the first riser reactor and the second riser reactor to circularly participate in reaction;

the regenerator I and the regenerator II are the same regenerator and are shared regenerators.

Referring now to FIG. 1, a preferred embodiment of the present invention will be described in detail, wherein the method for catalytic conversion of hydrocarbon oil comprises:

(1) introducing a hydrogenated catalytic diesel raw material 1a and a catalyst into a first riser reactor 3a under the action of first lifting steam 2a, performing catalytic cracking reaction to obtain a first reaction product and a carbon-carrying catalyst, and enabling the first reaction product and the carbon-carrying catalyst to flow upwards together, wherein the first reaction product and the carbon-carrying catalyst enter a first settler 4a for oil separation to obtain reaction oil gas I6 a and the carbon-carrying catalyst;

the separated reaction oil gas I6 a can enter a subsequent separation system as required to separate liquefied gas, gasoline, diesel oil and other products;

(2) after being stripped by a first stripper 5a, the catalyst with carbon enters a regenerator 8a through a first riser to be regenerated for scorching and is then introduced into a second riser reactor 15a under the action of second lifting steam 13a to contact with a gasoline fraction 12a and an alkyl transfer agent 14a introduced into the second riser reactor 15a for alkyl transfer reaction, so as to obtain a second reaction product;

and the second reaction product enters a second settler 16a for oil separation to obtain reaction oil gas II 18a and a carbon-containing catalyst obtained through transalkylation reaction, the carbon-containing catalyst obtained through transalkylation reaction is subjected to steam stripping by a second steam stripper 17a, flows through a second inclined tube to be regenerated 19a and is introduced into a regenerator 8a for regeneration, and the obtained regenerated catalyst I is introduced into the first riser reactor and the second riser reactor.

A regenerator main air 9a is arranged at the bottom of the regenerator 8a, and the regenerator main air 9a is used for conveying main air into the regenerator 8 a; and a settling cyclone separator 10a is arranged on the side surface inside the regenerator 8a, and the settling cyclone separator 10a is used for settling and separating the spent catalyst in the regenerator 8a again to obtain regenerated flue gas 11a and the regenerated catalyst I.

According to another preferred embodiment of the present invention, the method for catalytic conversion of hydrocarbon oil comprises:

(1) carrying out catalytic cracking reaction on a hydrogenated catalytic diesel raw material and a catalyst in a first riser reactor to obtain reaction oil gas I and a catalyst with carbon;

(2) directly introducing the catalyst with carbon into a second riser reactor without regeneration so as to contact with gasoline fraction and a transalkylation agent in the catalyst and carry out transalkylation reaction to obtain reaction oil gas II and a spent catalyst;

introducing the spent catalyst obtained in the step (2) into a regenerator I for regeneration, and introducing the obtained regenerated catalyst I into the first riser reactor and the second riser reactor to circularly participate in the reaction.

In another embodiment provided by the present invention, the present invention adopts a catalyst series connection relay in a double riser reactor, and the catalytic cracking reaction and the transalkylation reaction are reacted in a divisional manner, and the catalyst after the series reaction is subjected to oil separation by a settler and a stripper, and is regenerated by a regenerator; moreover, the top of the first riser reactor is provided with independent quick separation equipment for separating the oil agent; compared with the prior art, the scheme can greatly improve the yield of the dimethylbenzene, particularly high-value p-dimethylbenzene, save equipment and reduce cost on the premise of keeping the product distribution of catalytic products and little change of gasoline composition and weight.

Referring now to FIG. 2, another preferred embodiment of the present invention will be described in detail, wherein the method for catalytic conversion of hydrocarbon oil comprises:

(1) introducing a hydrogenated catalytic diesel raw material 1b and a catalyst into a first riser reactor 3b under the action of first lifting steam 2b, carrying out catalytic cracking reaction to obtain a first reaction product and a carbon-carrying catalyst, and enabling the first reaction product and the carbon-carrying catalyst to flow upwards together, and enabling the first reaction product and the carbon-carrying catalyst to enter a rapid separation device 4b for oil separation to obtain reaction oil gas I5 b and the carbon-carrying catalyst;

the separated reaction oil gas I5 b can enter a subsequent separation system as required to separate products such as liquefied gas, gasoline, diesel oil and the like;

(2) the catalyst with carbon is introduced into the second riser reactor 8b under the action of the second lifting steam 7b to contact with the gasoline fraction 18b and the alkyl transfer agent 6b introduced into the second riser reactor 8b for alkyl transfer reaction to obtain a second reaction product;

and the second reaction product enters a second settler 9b for oil separation to obtain reaction oil gas II 11b and a carbon-containing catalyst obtained through transalkylation reaction, the carbon-containing catalyst obtained through transalkylation reaction is stripped through a stripper 10b, flows through a to-be-regenerated vertical pipe 12b and is introduced into a regenerator 13b for regeneration, and the obtained regenerated catalyst I is introduced into the first riser reactor 3 b.

A regenerator main air 14b is arranged at the bottom of the regenerator 13b, and the regenerator main air 14b is used for conveying main air into the regenerator 13 b; the cyclone separator 15b is arranged on the side surface inside the regenerator 13b, and the cyclone separator 15b is used for settling and separating the catalyst to be regenerated in the regenerator 13b again to obtain regenerated flue gas 16b and the regenerated catalyst I; an external heat collector 17b is provided on the side of the regenerator 13 b.

In the present invention, the regenerator, the settler, the settling cyclone separator, the external heat remover, the fast separation equipment (for example, VQS fast separation equipment) and the cyclone separator are all common equipment in the art, and the present invention is not limited thereto, as long as the corresponding functions can be realized, and will not be described herein again.

In the invention, the stripping medium in the stripper is preferably stripped by adopting water vapor, and the effect of the stripping medium is to replace oil gas filled between catalyst particles and in particle pores, thereby improving the yield of oil products. The amount of steam used for stripping is well known to those skilled in the art. Generally, the amount of steam used for stripping is from 0.1 to 0.8% by weight, preferably from 0.2 to 0.4% by weight, based on the amount of catalyst circulated.

The present invention will be described in detail below by way of examples. In the following examples, the starting materials are all commercially available products unless otherwise specified.

Wherein, the raw materials: hydrocatalytic diesel, purchased from Yanshan division of the China petrochemical group company, with properties listed in Table 2;

catalyst: CGP-YS catalyst, purchased from China petrochemical catalyst division, with properties as shown in Table 1;

a transalkylation agent: toluene.

In the following examples, medium-sized double riser reactors were used, which included a first riser reactor and a second riser reactor; the first riser reactor is of a cylindrical structure with the total height of 10 meters and the diameter of 25 millimeters, and the lowest part of the riser is a pre-lifting section; the second riser reactor is a cylindrical structure with the total height of 8 meters and the diameter of 25 millimeters, and the lowest part of the riser is a pre-lifting section.

The composition of the reaction oil or gas or gasoline described in the examples below was determined using a gas chromatograph.

Example 1

This example is intended to illustrate the process for the catalytic conversion of hydrocarbon oils according to the invention.

As shown in fig. 1, (1) preheated hydrocatalytic diesel oil is taken as a raw material 1a and is introduced into a first riser reactor 3a under the action of first lifting steam 2a, and is contacted with a fresh CGP-YS catalyst or a regenerated CGP-YS catalyst to carry out catalytic cracking reaction, so as to obtain a first reaction product and a carbon-carrying catalyst, and the first reaction product and the carbon-carrying catalyst flow upwards together, and the first reaction product and the carbon-carrying catalyst enter a first settler 4a to carry out oil separation, so as to obtain a reaction oil gas I6 a and the carbon-carrying catalyst; the carbon content in the carbon-carrying catalyst is 1.12 wt%;

the separated reaction oil gas I6 a enters a subsequent separation system, and products such as liquefied gas, gasoline, diesel oil and the like are separated to obtain a gasoline fraction 12a, wherein the distillation range of the gasoline fraction 12a is 71-202 ℃, and the weight of the gasoline fraction accounts for 50% of the weight of the raw material catalytic diesel oil;

introducing said preheated gasoline fraction 12a into a second riser reactor 15a together with toluene;

in the material flow, the weight ratio of the hydrogenation catalytic diesel oil, the gasoline fraction and the toluene in unit time is 10: 5: 1;

(2) after being stripped by a first stripper 5a, the catalyst with carbon enters a regenerator 8a through a first riser to be regenerated for scorching and is then introduced into a second riser reactor 15a under the action of second lifting steam 13a to contact with a gasoline fraction 12a and an alkyl transfer agent 14a introduced into the second riser reactor 15a for alkyl transfer reaction, so as to obtain a second reaction product;

and the second reaction product enters a second settler 16a for oil separation to obtain reaction oil gas II 18a and a carbon-containing catalyst obtained through transalkylation reaction, the carbon-containing catalyst obtained through transalkylation reaction is subjected to steam stripping by a second steam stripper 17a, flows through a second inclined tube to be regenerated 19a and is introduced into a regenerator 8a for regeneration, and the obtained regenerated catalyst II is introduced into the first riser reactor and the second riser reactor. The carbon content in the regenerated catalyst II was 0.01 wt%.

The process parameters involved in this example are shown in table 3. The product distribution of the reaction oil gas II is shown in Table 4, and the composition of gasoline in the reaction oil gas II is shown in Table 5.

Comparative example 1

The comparative example employed a medium size single riser reactor having a cylindrical structure with a total height of 10 meters and a diameter of 25 millimeters, the lowermost portion of the riser being a pre-lift section.

Introducing a hydrogenated catalytic diesel raw material 1a preheated at 200 ℃ into the bottom of a single riser reactor under the action of pre-lifting steam, mixing the hydrogenated catalytic diesel raw material with a regenerated catalyst or a fresh catalyst for reaction, then making the hydrogenated catalytic diesel raw material flow upwards to an outlet of the single riser reactor and enter a settler, and separating the mixture by a cyclone separator to obtain a catalyst with carbon and a reaction product; wherein the reaction temperature of the single riser reactor is 502 ℃ and the pressure is 140 kPa; the dosage of the pre-lifting steam is 5 wt% of the raw oil, the catalyst-oil ratio (weight ratio of the catalyst to the raw oil) is 6, and the retention time (namely reaction time) of the raw oil in the single-riser reactor is 4 seconds.

And the reaction product enters a subsequent separation system to be separated to obtain product oil, the catalyst with carbon is stripped to obtain a spent catalyst, and the spent catalyst enters a regenerator to be burned and regenerated at 670 ℃ and then recycled.

The process parameters involved in this example are shown in table 3. The product distribution of the product oil obtained is shown in table 4, and the composition of the gasoline in said product oil is shown in table 5.

Example 2

Catalytic conversion of a hydrocarbon oil was carried out in the same manner as in example 1 except that in step (1), the gasoline fraction 12a and toluene were separately introduced into the second riser reactor 15a, respectively, the feeding position of the gasoline fraction 12a was upstream of the feeding position of the toluene in terms of the flow direction, and the transalkylation agent was introduced after the catalytic gasoline raw material was introduced for 1 s.

Example 3

As shown in fig. 2, (1) introducing a hydrocatalysis diesel raw material 1b into a first riser reactor 3b under the action of first lifting steam 2b, contacting with a catalyst (CGP-YS catalyst) or a regenerated CGP-YS catalyst, performing catalytic cracking reaction to obtain a first reaction product and a carbon-carrying catalyst, enabling the first reaction product and the carbon-carrying catalyst to flow upwards together, and enabling the first reaction product and the carbon-carrying catalyst to enter a quick separation device 4b for oil separation to obtain a reaction oil gas I5 b and the carbon-carrying catalyst; the carbon content in the carbon-carrying catalyst is 1.12 wt%;

the separated reaction oil gas I5 b can enter a subsequent separation system as required to separate liquefied gas, gasoline, diesel oil and other products to obtain a gasoline fraction 18b, wherein the distillation range of the gasoline fraction 18b is 71-202 ℃, and the weight of the gasoline fraction accounts for 50% of the weight of the raw material catalytic diesel oil;

introducing said preheated gasoline fraction 18b into a second riser reactor 8b together with toluene;

in the material flow, the weight ratio of the hydrogenation catalytic diesel oil, the gasoline fraction and the toluene in unit time is 10: 5: 1;

(2) the catalyst with carbon is introduced into the second riser reactor 8b under the action of the second lifting steam 7b to contact with the gasoline fraction 18b and the alkyl transfer agent 6b introduced into the second riser reactor 8b for alkyl transfer reaction to obtain a second reaction product;

and the second reaction product enters a second settler 9b for oil separation to obtain reaction oil gas II 11b and a carbon-containing catalyst obtained through transalkylation reaction, the carbon-containing catalyst obtained through transalkylation reaction is stripped through a stripper 10b, flows through a to-be-regenerated vertical pipe 12b and is introduced into a regenerator 13b for regeneration, and the obtained regenerated catalyst I is introduced into the first riser reactor 3 b. The carbon content in the regenerated catalyst I was 0.01 wt%.

The process parameters involved in this example are shown in table 3. The product distribution of the reaction oil gas II is shown in Table 4, and the composition of gasoline in the reaction oil gas II is shown in Table 5.

Example 4

Catalytic conversion of hydrocarbon oil was carried out according to the method of example 3, except that in the stream, in unit time, the diesel oil was hydrocatalytically: gasoline fraction: the weight ratio of toluene is 10: 5: 2.

examples 5 to 8

Catalytic conversion of hydrocarbon oil was carried out in the same manner as in example 3 except that the process parameters shown in Table 3 were used in place of those of example 3.

TABLE 1

TABLE 2

TABLE 3

Note: the pre-lifting steam quantity of the first lifting pipe refers to the weight part of steam relative to 100 weight parts of hydrocatalytic diesel raw material; the pre-lifting steam amount of the second lifting pipe refers to the weight part of steam relative to 100 weight parts of gasoline fraction; the first riser and the second riser are respectively a first riser reactor and a second riser reactor; the feeding time difference of the second riser refers to the difference between the introduction time of the toluene and the introduction time of the gasoline fraction; the first riser catalyst-to-oil ratio refers to the weight ratio of the dosage of the catalyst in the first riser to the dosage of the hydrocatalytic diesel raw material; the weight ratio of the catalyst to the gasoline fraction in the second riser is the weight ratio of the catalyst to the gasoline fraction in the second riser.

Table 3 (continuation watch)

TABLE 4

Distribution of reaction oil gas II product, wt%	Example 1	Example 2	Comparative example 1	Example 3	Example 4
						Dry gas	4.5	4.7	4.3	4.6	4.7
Liquefied gas	10.6	10.8	10.4	10.6	10.8
						Gasoline (gasoline)	56.8	56.1	57.4	56.5	56.2
Diesel oil	24.0	24.1	24.0	24.1	24
						Oil slurry	0.4	0.5	0.3	0.4	0.5
Coke	3.7	3.8	3.6	3.8	3.8

Table 4 (continuation watch)

Distribution of reaction oil gas II product, wt%	Example 5	Example 6	Example 7	Example 8
					Dry gas	4.4	4.5	4.9	5.9
Liquefied gas	9.9	10.6	11.2	12.1
					Gasoline (gasoline)	55.4	56.6	55.4	54.2
Diesel oil	26.2	24.1	23.8	22.3
					Oil slurry	0.4	0.4	0.6	0.9
Coke	3.7	3.8	4.1	4.6

TABLE 5

Gasoline composition, wt%	Example 1	Example 2	Comparative example 1	Example 3	Example 4
						N-alkanes	13.6	15.7	13.5	13.6	15.1
Isoalkanes	20.6	21.1	20.2	20.7	20.9
						Olefins	14.4	14.5	14.3	14.3	14.8
Cycloalkanes	16.6	14.7	16.4	16.7	14.9
						Aromatic hydrocarbons	34.8	34.0	35.6	34.7	34.3
Net yield of xylene, wt.%	14.3	15.1	8.6	14.7	15.6
						Net yield of p-xylene, wt.%	3.5	3.7	2.1	3.6	3.9
Octane number (xylene withdrawn), wt%	91.0	91.1	90.5	90.9	91.1

Table 5 (continuation watch)

Gasoline composition, wt%	Example 5	Example 6	Example 7	Example 8
					N-alkanes	13.6	13.1	11.7	11.2
Isoalkanes	20.5	21.6	20.6	19.8
					Olefins	14.2	12.7	16.5	18.2
Cycloalkanes	17.6	16.5	17.0	17.7
					Aromatic hydrocarbons	34.1	36.1	34.2	33.1
Net yield of xylene, wt.%	14.9	15.8	9.5	8.9
					Net yield of p-xylene, wt.%	3.8	4.0	2.7	2.2
Octane number (xylene withdrawn), wt%	90.9	91.0	90.6	90.7

As can be seen from tables 3-5, by adopting the method provided by the invention and controlling the reaction temperature of the second riser to be lower than that of the first riser, the modification effect of the gasoline fraction is more obvious, the yield of liquefied gas is improved by at least 0.2 percent, and the yield of other products is also improved. Particularly, the scheme of controlling the feeding time difference of the second riser to be not 0 is adopted, and better technical effect is obtained.

It can be seen from the comparison of examples 3 and 4 with comparative example 1 that the method provided by the present invention can control the temperature of the second riser reactor to be lower than the reaction temperature of the first riser reactor, and properly prolong the reaction time in the second riser reactor, so that the gasoline fraction upgrading effect is obvious, the yield of liquefied gas can be increased by at least 0.2%, and the yield of other products is increased.

As can be seen from Table 5, the method provided by the invention is particularly used for the second riser to guide and promote the transalkylation reaction of C7 aromatic hydrocarbon and heavy aromatic hydrocarbon above C9, so that the yield of high-value xylene and paraxylene in gasoline in reaction oil gas II is obviously improved. Especially p-xylene, the net yield increases from 2.1% to 3.5%, even 3.9%, by at least 1.4% and even 1.8%.

The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.