阅读说明：本技术 一种劣质油的加工方法和系统 (Processing method and system of inferior oil ) 是由 魏晓丽 龚剑洪 陈学峰 侯焕娣 申海平 张执刚 张策 梁家林 戴立顺 张久顺 侯 于 2019-03-04 设计创作，主要内容包括：本发明涉及一种劣质油的加工方法和系统,该方法包括：将劣质油在临氢条件下进行转化反应,所得转化产物进行分离,得到重馏分；将所得重馏分进行萃取分离,得到改质油和残渣；将所得改质油引入加氢改质单元进行加氢改质,得到气体产物、加氢改质轻油和加氢改质重油；将所得加氢改质重油引入催化裂解反应器的第一反应区进行第一催化裂解反应,所得反应油剂引入催化裂解反应器的第二反应区中进行第二催化裂解反应；将所得加氢改质轻油引入催化裂解反应器的第三反应区进行第三催化裂解反应。本发明的方法和系统具有高低碳烯烃产率。(The invention relates to a processing method and a system of inferior oil, wherein the method comprises the following steps: carrying out conversion reaction on the inferior oil under the hydrogen condition, and separating the obtained conversion product to obtain heavy fraction; extracting and separating the obtained heavy fraction to obtain modified oil and residue; introducing the obtained modified oil into a hydro-modifying unit for hydro-modifying to obtain a gas product, hydro-modified light oil and hydro-modified heavy oil; introducing the obtained hydro-modified heavy oil into a first reaction zone of a catalytic cracking reactor to perform a first catalytic cracking reaction, and introducing the obtained reaction oil into a second reaction zone of the catalytic cracking reactor to perform a second catalytic cracking reaction; and introducing the obtained hydro-upgrading light oil into a third reaction zone of the catalytic cracking reactor to carry out a third catalytic cracking reaction. The method and system of the invention have high yield of low carbon olefin.)

1. A method of processing a poor quality oil, the method comprising:

introducing the inferior oil into a conversion reaction unit to carry out conversion reaction under the hydrogen condition, and separating the obtained conversion product to obtain heavy fraction with the distillation range of more than 350 ℃;

introducing the obtained heavy fraction into an extraction separation unit to contact with an extraction solvent and carrying out extraction separation to obtain modified oil and residue;

introducing the obtained modified oil into a hydro-modifying unit for hydro-modifying to obtain a gas product, hydro-modified light oil and hydro-modified heavy oil;

introducing the obtained hydro-modified heavy oil into a first reaction zone of a catalytic cracking reactor to contact with a first catalytic cracking catalyst and carry out a first catalytic cracking reaction, introducing the obtained reaction oil into a second reaction zone of the catalytic cracking reactor to carry out a second catalytic cracking reaction, and obtaining a first catalyst to be generated and a first reaction product;

introducing the obtained hydro-modified light oil into a third reaction zone of a catalytic cracking reactor to contact with a second catalytic cracking catalyst and carry out a third catalytic cracking reaction to obtain a second spent catalyst and a second reaction product;

and regenerating the first spent catalyst and the second spent catalyst and returning the regenerated first spent catalyst and the second spent catalyst to the catalytic cracking reactor.

2. The process of claim 1, wherein said low grade oil comprises at least one selected from the group consisting of low grade crude oil, heavy oil, deoiled bitumen, coal derived oil, shale oil and petrochemical waste oil.

3. The process of claim 1 wherein the low quality oil meets one or more criteria selected from the group consisting of an API degree of less than 27, a distillation range of greater than 350 ℃, an asphaltene content of greater than 2 wt.%, and a heavy metal content of greater than 100 micrograms/gram based on the total weight of nickel and vanadium.

4. The process of claim 1, wherein said conversion reaction unit comprises a conversion reactor, said conversion reactor being a fluidized bed reactor;

the conversion reaction is carried out in the presence or absence of a conversion catalyst containing at least one selected from the group consisting of group VB metal compounds, group VIB metal compounds and group VIII metal compounds;

the conversion reaction conditions include: the temperature is 380-470 ℃, the hydrogen partial pressure is 10-25 MPa, and the volume of the inferior oil is emptyThe speed is 0.01-2 hours^-1The volume ratio of the hydrogen to the poor-quality oil is 500-5000, and the amount of the conversion catalyst is 10-50000 micrograms/g based on the weight of the poor-quality oil and calculated by the metal in the conversion catalyst.

5. The process of claim 1, wherein the conditions of the extractive separation comprise: the pressure is 3-12 MPa, the temperature is 55-300 ℃, and the extraction solvent is C₃-C₇The weight ratio of the hydrocarbon, the extraction solvent and the heavy fraction is (1-7): 1.

6. the process of claim 1, wherein the hydro-upgrading conditions comprise: the hydrogen partial pressure is 5.0-20.0 MPa, the reaction temperature is 330-^-1The volume ratio of hydrogen to oil is 300-3000; the catalyst used by the hydrogenation upgrading unit comprises a hydrofining catalyst and a hydrocracking catalyst, wherein the hydrofining catalyst comprises a carrier and an active metal component, and the active metal component is selected from VIB group metals and/or VIII group non-noble metals; the hydrocracking catalyst comprises zeolite, alumina, at least one group VIII metal component and at least one group VIB metal component.

7. The process of claim 6 wherein the hydrocracking catalyst comprises 3 to 60 wt% zeolite, 10 to 80 wt% alumina, 1 to 15 wt% nickel oxide and 5 to 40 wt% tungsten oxide based on the dry weight of the hydrocracking catalyst.

8. The process of claim 1, wherein the cut point of the hydroupgraded light oil and the hydroupgraded heavy oil is between 340 ℃ and 360 ℃, preferably between 345 ℃ and 355 ℃, more preferably 350 ℃.

9. The process of claim 1, wherein said first reaction zone is a riser reactor, said second reaction zone is a fluidized bed reactor, and said third reaction zone is a riser reactor.

10. The process of claim 1, wherein the conditions of the first catalytic cracking reaction comprise: the reaction temperature is 560 ℃ and 750 ℃, the reaction time is 1-10 seconds, and the weight ratio of the catalyst to the oil is 1-50; the conditions of the second catalytic cracking reaction include: the reaction temperature is 550-750 ℃, and the weight hourly space velocity is 0.5-20 h^-1；

The conditions of the third catalytic cracking reaction include: the reaction temperature is 600-750 ℃, the reaction time is 1-10 seconds, and the weight ratio of the catalyst to the oil is 1-100;

the feed weight ratio of the hydro-upgrading light oil to the hydro-upgrading heavy oil is 0.01: 1-0.5: 1.

11. the process of claim 1, wherein the first and second catalytic cracking catalysts each independently comprise, on a dry weight basis and based on the weight of the catalytic cracking catalyst, from 1 to 60 weight percent zeolite, from 5 to 99 weight percent inorganic oxide, and from 0 to 70 weight percent clay;

the zeolite comprises 50 to 100 wt% of a medium pore zeolite and 0 to 50 wt% of a large pore zeolite, based on the weight of the zeolite on a dry basis.

12. The process of claim 1, further comprising: returning the obtained residue to the conversion reaction unit for conversion reaction.

13. The process of claim 1, wherein the conversion of the conversion reaction is 30-70 wt%, the conversion being (weight of components with distillation range above 524 ℃ in the poor oil-weight of components with distillation range above 524 ℃ in the converted product)/weight of components with distillation range above 524 ℃ in the poor oil x 100 wt%; and/or

In the heavy fraction, the content of components with the distillation range between 350 ℃ and 524 ℃ is 20-60 wt%.

14. A processing system of inferior oil comprises a conversion reaction unit, an extraction separation unit, a hydro-upgrading unit and a catalytic cracking reactor, wherein the catalytic cracking reactor comprises a first reaction zone, a second reaction zone and a third reaction zone;

the conversion reaction unit is provided with an inferior oil inlet, a hydrogen inlet, a light fraction outlet and a heavy fraction outlet, the extraction separation unit is provided with an extraction solvent inlet, a raw material inlet, a modified oil outlet and a residue outlet, the hydrogenation modification unit is provided with a hydrogen inlet, a raw material inlet, a gas product outlet, a hydrogenation modified light oil outlet and a hydrogenation modified heavy oil outlet, the first reaction zone is provided with a catalyst inlet, a raw material inlet and an oil agent outlet, the second reaction zone is provided with an oil agent inlet and an oil agent outlet, and the third reaction zone is provided with a catalyst inlet, a raw material inlet and an oil agent outlet;

the heavy fraction outlet of the conversion reaction unit is communicated with the raw material inlet of the extraction separation unit, the modified oil outlet of the extraction separation unit is communicated with the raw material inlet of the hydro-modification unit, the hydro-modified heavy oil outlet of the hydro-modification unit is communicated with the raw material inlet of the first reaction zone, the oil agent outlet of the first reaction zone is communicated with the oil agent inlet of the second reaction zone, and the raw material inlet of the third reaction zone is communicated with the hydro-modified light oil outlet of the hydro-modification unit.

Technical Field

The invention relates to a processing method and a system of inferior oil.

Background

Ethylene and propylene are important petrochemical industry base stocks. Currently, about 98% of the world's ethylene comes from tubular furnace steam cracking technology, with 46% naphtha and 34% ethane in the ethylene production feed. About 62% of the propylene comes from the co-production of ethylene by steam cracking. The steam cracking technology is perfected day by day, and is a process consuming a large amount of energy, and is limited by the used high-temperature materials, and the potential of further improvement is very small.

With the slow recovery of the world economy, the oil demand is slowly increased, and the supply and demand of the world oil market are basically kept loose. The international energy agency considers that, on the supply side, the crude oil production in non-european peck countries, represented by the united states, will continue to rise in the coming years, and the global crude oil demand will tend to tighten in 2022; on the demand side, the global crude oil demand will continuously rise in the next 5 years, and in 2019, 1 hundred million barrels per day will be broken through; the processing amount of unconventional oil and inferior heavy oil is increased year by year. Therefore, the method for producing chemical raw materials such as low-carbon olefin to the maximum extent by utilizing unconventional oil or poor-quality oil is the key and key point for broadening the source of the raw materials for producing the low-carbon olefin, adjusting the product structure, improving the quality and enhancing the effect of the low-carbon olefin in petrochemical enterprises.

Chinese patent CN101045884A discloses a method for producing clean diesel oil and low-carbon olefin from residual oil and heavy distillate oil. The method comprises the steps that residual oil and optional catalytic cracking slurry oil enter a solvent deasphalting unit, the obtained deasphalted oil and optional heavy distillate oil enter a hydrogenation unit, hydrocracking reaction is carried out in the presence of hydrogen, and light and heavy naphtha fraction, diesel oil fraction and hydrogenation tail oil are obtained by separating products; the hydrogenated tail oil enters a catalytic cracking unit to carry out catalytic cracking reaction, and products are separated to obtain low-carbon olefin, gasoline fraction, diesel oil fraction and slurry oil; the diesel oil is recycled to the catalytic cracking unit and all or part of the oil slurry is returned to the solvent deasphalting unit. The method processes the mixture of vacuum residue and catalytic cracking slurry oil, and can obtain the yield of propylene of about 27.3 weight percent and the yield of ethylene of 10.6 weight percent.

WO2015084779a1 discloses a process for producing lower olefins, especially propylene, using a combination of solvent deasphalting and high severity catalytic cracking. The method comprises the following steps: mixing the vacuum residue oil and the solvent, and then performing solvent deasphalting treatment to obtain deasphalted oil and deoiled asphalt rich in the solvent; the deasphalted oil rich in solvent enters a heavy oil deep catalytic cracking device for deep cracking reaction after the solvent is separated, and a target product rich in low-carbon olefin, especially propylene is obtained. The method comprises the steps of firstly carrying out solvent deasphalting treatment on residual oil, then realizing the high-efficiency conversion of deasphalted oil and generating low-carbon olefin through a combined process, but not using and processing the deasphalted oil.

Chinese patent CN201510769091 discloses a residual oil treatment method, which comprises a solvent deasphalting device, a hydrogenation pretreatment reaction zone, a hydrotreating reaction zone and a catalytic cracking reaction zone; the process method comprises the following steps: the method comprises the steps of fractionating a residual oil raw material to obtain a light fraction and a heavy fraction, treating the heavy fraction in a solvent deasphalting device to obtain deasphalted oil and deoiled asphalt, mixing the light fraction, the deasphalted oil and hydrogen, sequentially passing through a hydrogenation pretreatment reaction zone and a hydrotreating reaction zone which are connected in series, carrying out gas-liquid separation on reaction effluent in the hydrotreating reaction zone, circulating a gas phase to the hydrogenation pretreatment reaction zone and/or the hydrotreating reaction zone, directly feeding a liquid phase into a catalytic cracking reaction zone to carry out catalytic cracking reaction, and separating the catalytic cracking reaction effluent to obtain dry gas, liquefied gas, a catalytic cracking gasoline fraction, a catalytic cracking diesel fraction, catalytic cracking heavy cycle oil and catalytic cracking slurry oil. The method can prolong the stable operation period of the device.

Chinese patent CN01119808.7 discloses a high-sulfur high-metal residual oil conversion method, wherein deasphalted oil obtained by extracting residual oil, slurry oil and solvent, and heavy cycle oil and optional solvent refined extract oil enter a hydrotreater together, react in the presence of hydrogen and a hydrogenation catalyst, and the product is separated to obtain gas, naphtha, hydrogenated diesel oil and hydrogenated tail oil, wherein the hydrogenated tail oil enters a catalytic cracking device, and is subjected to cracking reaction in the presence of a cracking catalyst, and the reaction product is separated, wherein the heavy cycle oil can be circulated to the hydrotreater, and the slurry oil is circulated to the solvent deasphalting device. The method reduces the investment and operation cost of a hydrotreater and improves the yield and quality of the light oil.

In order to obtain more low-carbon olefins from poor-quality oil, the prior art adopts a technical method combining solvent deasphalting and hydrotreating to provide a high-quality raw material for catalytic cracking, but the yield of deasphalted oil is low, the yield is limited from the economical point of the whole process, and in addition, the deasphalted oil is not well utilized, so that the utilization rate of the poor-quality oil in the prior art is low, and more residues are still generated. Therefore, it is necessary to develop a green and efficient conversion technology for producing low-carbon olefins from inferior oil, so as to increase the utilization rate of the inferior oil and to produce more chemical raw materials with high added values.

Disclosure of Invention

The invention aims to provide a method and a system for processing inferior oil, which have high yield of low-carbon olefin.

In order to achieve the above object, the present invention provides a method for processing inferior oil, comprising:

introducing the inferior oil into a conversion reaction unit to carry out conversion reaction under the hydrogen condition, and separating the obtained conversion product to obtain heavy fraction with the distillation range of more than 350 ℃;

introducing the obtained heavy fraction into an extraction separation unit to contact with an extraction solvent and carrying out extraction separation to obtain modified oil and residue;

introducing the obtained modified oil into a hydro-modifying unit for hydro-modifying to obtain a gas product, hydro-modified light oil and hydro-modified heavy oil;

introducing the obtained hydro-modified heavy oil into a first reaction zone of a catalytic cracking reactor to contact with a first catalytic cracking catalyst and carry out a first catalytic cracking reaction, introducing the obtained reaction oil into a second reaction zone of the catalytic cracking reactor to carry out a second catalytic cracking reaction, and obtaining a first catalyst to be generated and a first reaction product;

introducing the obtained hydro-modified light oil into a third reaction zone of a catalytic cracking reactor to contact with a second catalytic cracking catalyst and carry out a third catalytic cracking reaction to obtain a second spent catalyst and a second reaction product;

and regenerating the first spent catalyst and the second spent catalyst and returning the regenerated first spent catalyst and the second spent catalyst to the catalytic cracking reactor.

Optionally, the low-grade oil comprises at least one selected from the group consisting of low-grade crude oil, heavy oil, deoiled bitumen, coal-derived oil, shale oil, and petrochemical waste oil.

Optionally, the low quality oil meets one or more criteria selected from the group consisting of an API degree of less than 27, a distillation range of greater than 350 ℃, an asphaltene content of greater than 2 wt.%, and a heavy metal content of greater than 100 micrograms/gram, based on the total weight of nickel and vanadium.

Optionally, the conversion reaction unit comprises a conversion reactor, and the conversion reactor is a fluidized bed reactor;

the conversion reaction is carried out in the presence or absence of a conversion catalyst containing at least one selected from the group consisting of group VB metal compounds, group VIB metal compounds and group VIII metal compounds;

the conversion reaction conditions include: the temperature is 380-470 ℃, the hydrogen partial pressure is 10-25 MPa, and the volume space velocity of the inferior oil is 0.01-2 hours^-1The volume ratio of the hydrogen to the poor-quality oil is 500-5000, and the amount of the conversion catalyst is 10-50000 micrograms/g based on the weight of the poor-quality oil and calculated by the metal in the conversion catalyst.

Optionally, the extraction separation conditions include: the pressure is 3-12 MPa, the temperature is 55-300 ℃, and the extraction solvent is C₃-C₇The weight ratio of the hydrocarbon, the extraction solvent and the heavy fraction is (1-7): 1.

optionally, the hydro-upgrading conditions include: the hydrogen partial pressure is 5.0-20.0 MPa, the reaction temperature is 330-^-1The volume ratio of hydrogen to oil is 300-3000.

The catalyst used by the hydrogenation upgrading unit comprises a hydrofining catalyst and a hydrocracking catalyst, wherein the hydrofining catalyst comprises a carrier and an active metal component, and the active metal component is selected from VIB group metals and/or VIII group non-noble metals; the hydrocracking catalyst comprises zeolite, alumina, at least one group VIII metal component and at least one group VIB metal component. Preferably, the hydrocracking catalyst comprises 3 to 60 wt% of zeolite, 10 to 80 wt% of alumina, 1 to 15 wt% of nickel oxide and 5 to 40 wt% of tungsten oxide based on the dry weight of the hydrocracking catalyst, wherein the zeolite is a Y-type zeolite.

The filling volume ratio of the hydrofining catalyst to the hydrocracking catalyst is 1-5: 1, according to the flow direction of reaction materials, the hydrofining catalyst is filled at the upstream of the hydrocracking catalyst.

Optionally, the cut point of the hydro-upgrading light oil and the hydro-upgrading heavy oil is between 340 ℃ and 360 ℃, preferably between 345 ℃ and 355 ℃, and more preferably 350 ℃.

Optionally, the first reaction zone is a riser reactor, the second reaction zone is a fluidized bed reactor, and the third reaction zone is a riser reactor.

Optionally, the conditions of the first catalytic cracking reaction include: the reaction temperature is 560 ℃ and 750 ℃, the reaction time is 1-10 seconds, and the weight ratio of the catalyst to the oil is 1-50; the conditions of the second catalytic cracking reaction include: the reaction temperature is 550-750 ℃, and the weight hourly space velocity is 0.5-20 h^-1；

The conditions of the third catalytic cracking reaction include: the reaction temperature is 600-750 ℃, the reaction time is 1-10 seconds, and the weight ratio of the catalyst to the oil is 1-100;

the feed weight ratio of the hydro-upgrading light oil to the hydro-upgrading heavy oil is 0.01: 1-0.5: 1.

optionally, the first and second catalytic cracking catalysts each independently comprise, on a dry basis weight and based on the weight of the catalytic cracking catalyst, from 1 to 60 weight percent zeolite, from 5 to 99 weight percent inorganic oxide, and from 0 to 70 weight percent clay;

the zeolite comprises 50 to 100 wt% of a medium pore zeolite and 0 to 50 wt% of a large pore zeolite, based on the weight of the zeolite on a dry basis.

Optionally, the method further includes: returning the obtained residue to the conversion reaction unit for conversion reaction.

Optionally, the conversion rate of the conversion reaction is 30-70 wt%, and the conversion rate of the conversion reaction is (the weight of the component with the distillation range above 524 ℃ in the inferior oil-the weight of the component with the distillation range above 524 ℃ in the conversion product)/the weight of the component with the distillation range above 524 ℃ in the inferior oil x 100 wt%; and/or

In the heavy fraction, the content of components with the distillation range between 350 ℃ and 524 ℃ is 20-60 wt%.

The invention also provides a processing system of the inferior oil, which comprises a conversion reaction unit, an extraction separation unit, a hydro-upgrading unit and a catalytic cracking reactor, wherein the catalytic cracking reactor comprises a first reaction zone, a second reaction zone and a third reaction zone;

the conversion reaction unit is provided with an inferior oil inlet, a hydrogen inlet, a light fraction outlet and a heavy fraction outlet, the extraction separation unit is provided with an extraction solvent inlet, a raw material inlet, a modified oil outlet and a residue outlet, the hydrogenation modification unit is provided with a hydrogen inlet, a raw material inlet, a gas product outlet, a hydrogenation modified light oil outlet and a hydrogenation modified heavy oil outlet, the first reaction zone is provided with a catalyst inlet, a raw material inlet and an oil agent outlet, the second reaction zone is provided with an oil agent inlet and an oil agent outlet, and the third reaction zone is provided with a catalyst inlet, a raw material inlet and an oil agent outlet;

the heavy fraction outlet of the conversion reaction unit is communicated with the raw material inlet of the extraction separation unit, the modified oil outlet of the extraction separation unit is communicated with the raw material inlet of the hydro-modification unit, the hydro-modified heavy oil outlet of the hydro-modification unit is communicated with the raw material inlet of the first reaction zone, the oil agent outlet of the first reaction zone is communicated with the oil agent inlet of the second reaction zone, and the raw material inlet of the third reaction zone is communicated with the hydro-modified light oil outlet of the hydro-modification unit.

Compared with the prior art, the invention has the following advantages:

1. the method can process the inferior oil with high metal and high asphaltene content, realizes the efficient lightening of the asphaltene by introducing the conversion reaction of the inferior oil, and greatly reduces the residue amount.

2. The distillation range and the composition of the raw materials for extraction and separation are optimized, the extraction and separation process is easy to operate, and the physical properties of the residues obtained in the extraction and separation process are improved, so that the subsequent division of labor is facilitated.

3. Can provide high-quality raw materials without metal and asphaltene for catalytic cracking, and realize the maximum production of chemical raw materials.

4. The high-quality hydro-upgrading light oil obtained by the hydro-upgrading unit can be used as a catalytic cracking feed to further produce ethylene and propylene, and the excessive pressure of the diesel market is relieved.

5. The high-value utilization of the inferior oil is realized, the efficient green conversion of the inferior oil is realized, and the production of chemical raw materials, namely low-carbon olefin from the low-quality oil is realized.

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

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 includes a schematic flow diagram of an embodiment of the method of the present invention and a schematic structural diagram of an embodiment of the system of the present invention.

Description of the reference numerals

1 first reaction zone 2 regenerator 3 settler

4 stripping section 5 degassing tank 6 cyclone separator

7 gas collection chamber 8 spent inclined tube 9 spent slide valve

10 line 11 line 12 regeneration pipe chute

13 regenerative spool valve 14 line 15 line

16 line 17 line 18 line

18 line 20 large oil gas line 21 line

22 air distributor 23 line 24 cyclone

25 flue gas duct 26, second reaction zone 27, third reaction zone

28 line 29 line 30 conversion reaction unit

31 line 32 line 33 line

34 line 35 line 36 extractive separation unit

37 line 38 line 39 line

40 hydro-upgrading unit 41 pipeline

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The invention provides a processing method of inferior oil, which comprises the following steps:

introducing the inferior oil into a conversion reaction unit to carry out conversion reaction under the hydrogen condition, and separating the obtained conversion product to obtain heavy fraction with the distillation range of more than 350 ℃;

introducing the obtained heavy fraction into an extraction separation unit to contact with an extraction solvent and carrying out extraction separation to obtain modified oil and residue;

introducing the obtained modified oil into a hydro-modifying unit for hydro-modifying to obtain a gas product, hydro-modified light oil and hydro-modified heavy oil;

introducing the obtained hydro-modified heavy oil into a first reaction zone of a catalytic cracking reactor to contact with a first catalytic cracking catalyst and carry out a first catalytic cracking reaction, introducing the obtained reaction oil into a second reaction zone of the catalytic cracking reactor to carry out a second catalytic cracking reaction, and obtaining a first catalyst to be generated and a first reaction product;

introducing the obtained hydro-modified light oil into a third reaction zone of a catalytic cracking reactor to contact with a second catalytic cracking catalyst and carry out a third catalytic cracking reaction to obtain a second spent catalyst and a second reaction product;

and regenerating the first spent catalyst and the second spent catalyst and returning the regenerated first spent catalyst and the second spent catalyst to the catalytic cracking reactor.

According to the present invention, low-grade oils are well known to those skilled in the art, and for example, the low-grade oils may include at least one selected from the group consisting of low-grade crude oil, heavy oil, deoiled bitumen, coal-derived oil, shale oil, and petrochemical waste oil. The heavy oil refers to distillate oil or residual oil with a boiling point above 350 ℃, and the distillate oil generally refers to fraction products obtained by atmospheric distillation and vacuum distillation of crude oil or secondary processing oil, such as heavy diesel oil, heavy gas oil, lubricating oil fraction or cracking raw materialEtc.; the residue refers to a bottom distillate obtained by atmospheric and vacuum distillation of crude oil, the atmospheric distillation bottom distillate is generally called atmospheric residue (generally a fraction with a boiling point of more than 350 ℃), the vacuum distillation bottom distillate is generally called vacuum residue (generally a fraction with a boiling point of more than 500 ℃ or 524 ℃), the residue can be at least one selected from topped crude oil, heavy oil obtained from oil sand bitumen and heavy oil with a primary boiling point of more than 350 ℃, and the topped crude oil refers to oil discharged from the bottom of a primary distillation tower or the bottom of a flash tower when the crude oil is fractionated in an atmospheric and vacuum distillation process; the inferior crude oil is thick oil, which refers to crude oil with high content of asphaltene and colloid and high viscosity, and the density of the ground is generally more than 0.943 g/cm at 20 DEG C³The crude oil with the viscosity of the underground crude oil being more than 50 centipoises is called thick oil; the deasphalted oil is rich in asphaltene and rich in aromatic components, which are obtained by contacting, dissolving and separating raw oil with a solvent and at the bottom of an extraction tower in a solvent deasphalting device, and can be divided into propane deasphalted asphalt, butane deoiled asphalt, pentane deoiled asphalt and the like according to the difference of the types of the solvents; the coal derived oil is a liquid fuel obtained by taking coal as a raw material and performing chemical processing, and can be at least one selected from coal liquefied oil generated by coal liquefaction and coal tar generated by coal pyrolysis; shale oil is brown sticky paste obtained by low-temperature dry distillation of oil shale, and has pungent odor and high nitrogen content; the petrochemical waste oil may be at least one selected from the group consisting of petrochemical waste oil sludge, petrochemical oil residue, and refined products thereof. Other low quality oils known to those skilled in the art may also be used alone or in combination as low quality oils for the conversion reaction and the present invention is not further described herein. The low quality oil preferably meets one or more criteria selected from the group consisting of an API degree of less than 27, a distillation range of greater than 350 ℃ (preferably greater than 500 ℃, more preferably greater than 524 ℃), an asphaltene content of greater than 2 wt.% (preferably greater than 5 wt.%, more preferably greater than 10 wt.%, even more preferably greater than 15 wt.%), and a heavy metal content of greater than 100 micrograms/gram, based on the total weight of nickel and vanadium.

According to the invention, the conversion reaction is essentially a thermal conversion reaction, which means that the poor oil is thermally converted in the presence of hydrogen and conversion products are obtained which contain at least heavy fractions and which may also contain light fractions having a lower distillation range than the heavy fractions.

In one embodiment, the conversion reaction unit comprises a conversion reactor, and the conversion reaction can be carried out in a fluidized bed reactor by using a solid-liquid suspension as a catalyst, so that the conversion reactor can be a fluidized bed reactor, and the fluidized bed reactor is a reactor in which reaction raw materials and the catalyst are reacted in a flowing state, and generally comprises a slurry bed reactor, a suspended bed reactor and a fluidized bed reactor, and the slurry bed reactor is preferred in the invention.

In one embodiment, the conversion reaction is carried out in the presence or absence of a conversion catalyst comprising at least one member selected from the group consisting of a group VB metal compound, a group VIB metal compound, and a group VIII metal compound; preferably at least one of Mo compound, W compound, Ni compound, Co compound, Fe compound, V compound and Cr compound, for example at least one selected from molybdenum naphthenate, nickel naphthenate, ammonium molybdate, organic molybdenum, organic vanadium and hematite; the conditions of the conversion reaction may include: the temperature is 380-470 ℃, preferably 400-440 ℃, the hydrogen partial pressure is 10-25 MPa, preferably 13-20 MPa, and the volume space velocity of the inferior oil is 0.01-2 hours^-1Preferably 0.1 to 1.0 hour^-1The volume ratio of the hydrogen to the poor-quality oil is 500-5000, preferably 800-2000, and the amount of the conversion catalyst is 10-50000 micrograms/g, preferably 30-25000 micrograms/g based on the weight of the poor-quality oil and the metal in the conversion catalyst.

In one embodiment, when the process of the present invention is carried out in a conversion reaction unit, it is generally carried out as follows: the poor oil, hydrogen and the conversion catalyst enter a conversion reactor of a conversion reaction unit for reaction, and the reaction product is separated into a gas product and a liquid product to finally obtain heavy fraction with the distillation range of more than 350 ℃.

According to the invention, the extraction separation is used for separating the easily processed modified oil in the heavy fraction, and the residue is thrown out or returned for conversion reaction, and the extraction separation can be carried out at a certain temperatureAnd an extraction solvent under pressure, preferably in countercurrent contact with the heavy fraction, and can be carried out in any extraction apparatus, such as an extraction column, under separation conditions including: the pressure is 3-12 MPa, preferably 3.5-10 MPa, the temperature is 55-300 deg.C, preferably 70-220 deg.C, and the extraction solvent is C₃-C₇A hydrocarbon, preferably C₃-C₅Alkane and C₃-C₅At least one of olefins, more preferably C₃-C₄Alkane and C₃-C₄At least one olefin, the weight ratio of the extraction solvent to the heavy fraction being (1-7): 1, preferably (1.5-5): 1. other conventional extraction methods can be adopted by the person skilled in the art for extraction, and the description of the invention is omitted.

In one embodiment, when the process of the present invention is carried out in an extractive separation unit, the heavy fraction having a distillation range of greater than 350 ℃ obtained from the conversion reaction unit is sent to the extractive separation unit for countercurrent contact with an extraction solvent for extractive separation to obtain an upgraded oil and a residue. The residue can be returned to the conversion reaction unit for further conversion reaction, and the modified oil is sent to the hydro-upgrading unit.

According to the present invention, the hydro-upgrading can be carried out in any manner known in the art, without particular limitation, and can be carried out in any hydrogenation apparatus known in the art (e.g., fixed bed reactor, fluidized bed reactor), which can be reasonably selected by one skilled in the art. The hydro-upgrading conditions may include: the hydrogen partial pressure is 5.0-20.0 MPa, the preferential pressure is 8-15 MPa, the reaction temperature is 330-450 ℃, the preferential pressure is 350-420 ℃, and the volume space velocity is 0.1-3 hours^-1Preferably 0.3 to 1.5 hours^-1The volume ratio of hydrogen to oil is 300-3000, preferably 800-1500; the catalyst used in the hydroupgrading unit includes a hydrorefining catalyst and a hydrocracking catalyst, and as the hydrorefining catalyst and the hydrocracking catalyst, for example, any catalyst conventionally used in the art for this purpose may be used or may be produced according to any production method conventionally known in the art, and the use of the hydrorefining catalyst and the hydrocracking catalyst in the stepThe amount is not particularly limited, as is conventional in the art. Specifically, the hydrorefining catalyst may comprise a carrier and an active metal component, and more specifically, examples of the active metal component include metals of group VIB and non-noble metals of group VIII of the periodic table, and particularly, a combination of nickel and tungsten, a combination of nickel, tungsten and cobalt, a combination of nickel and molybdenum, or a combination of cobalt and molybdenum. These active metal components may be used singly or in combination in any ratio. Examples of the carrier include alumina, silica, and amorphous silica-alumina. These carriers may be used singly or in combination in any ratio. The respective contents of the carrier and the active metal component are not particularly limited in the present invention, and conventional knowledge in the art can be referred to. The hydrocracking catalyst generally contains a cracking functional component, such as a zeolite, and specifically, the hydrocracking catalyst may include a zeolite, alumina, at least one group VIII metal component and at least one group VIB metal component, and the zeolite may be a Y-type zeolite. The hydrocracking catalyst may include 3 to 60 wt% zeolite, 10 to 80 wt% alumina, 1 to 15 wt% nickel oxide, and 5 to 40 wt% tungsten oxide, based on the dry weight of the hydrocracking catalyst. Other compositions of hydrocracking catalysts may also be employed by those skilled in the art. The invention has no special requirements on the loading sequence and the loading proportion of the hydrofining catalyst and the hydrocracking catalyst, for example, the hydrofining catalyst and the hydrocracking catalyst can be loaded in any ratio in a mixing way or loaded upstream and downstream, and the hydrofining catalyst is preferably loaded upstream of the hydrocracking catalyst, for example: the filling volume ratio of the hydrofining catalyst to the hydrocracking catalyst can be 1-5: 1, according to the flow direction of reaction materials, the hydrofining catalyst is filled at the upstream of the hydrocracking catalyst.

According to the invention, the hydro-upgrading light oil and the hydro-upgrading heavy oil are separated according to the distillation range, for example, the cut points of the hydro-upgrading light oil and the hydro-upgrading heavy oil are between 340 and 360 ℃, preferably between 345 and 355 ℃, and more preferably 350 ℃, and the distillation ranges of the hydro-upgrading light oil and the hydro-upgrading heavy oil can be partially overlapped according to the result of actual separation.

In one embodiment, when the process of the present invention is carried out in a hydro-upgrading unit, the upgraded oil from the extractive separation unit is reacted in the hydro-upgrading unit to obtain a hydro-upgraded heavy oil and a hydro-upgraded light oil, which are sent to different reaction zones of the catalytic cracking reactor, respectively.

According to the present invention, the catalytic cracking reactor comprises three reaction zones, and the specific structure of the three reaction zones is not particularly limited in the present invention, for example, the first reaction zone is a riser reactor, the second reaction zone is a fluidized bed reactor, and the third reaction zone is a riser reactor. More specifically, the first reaction zone and the second reaction zone are a riser reactor and a fluidized bed reactor which are connected in series, and the third reaction zone is a lifting reactor and is connected with the first reaction zone and the second reaction zone in parallel. The first reaction zone and the second reaction zone may be conventional catalytic cracking riser reactors, as are well known to those skilled in the art, in series with a fluidized bed reactor, for example, the riser reactor may be selected from the group consisting of constant diameter riser reactors and/or constant linear velocity riser reactors, preferably using constant diameter risers. The fluidized bed reactor is positioned at the downstream of the riser reactor and is connected with the outlet of the riser reactor, the riser reactor sequentially comprises a pre-lifting section and at least one reaction zone from bottom to top, and in order to ensure that the raw oil can be fully reacted, and the number of the reaction zones can be 2-8, preferably 2-3 according to the quality requirements of different target products. In the present invention, both "upstream" and "downstream" of the reactor are based on the direction of flow of the reaction mass, and upstream of the riser reactor is the bottom or lower portion of the reactor.

According to the present invention, the conditions of the catalytic cracking reaction may be selected as desired, for example, the conditions of the first catalytic cracking reaction may include: the reaction temperature is 560-750 ℃, the reaction temperature is preferably 580-730 ℃, the reaction temperature is more preferably 600-700 ℃, the reaction time is 1-10 seconds, the reaction time is preferably 2-5 seconds, and the weight ratio of the catalyst to the oil is 1-50, preferably 5-30; the conditions of the second catalytic cracking reaction may include: the reaction temperature is 550-750 ℃, preferably 550-730 ℃, and more preferablySelected from 570-720 ℃ and the weight hourly space velocity of 0.5-20 h^-1Preferably 2 to 10 hours^-1(ii) a The conditions of the third catalytic cracking reaction may include: the reaction temperature is 600-750 ℃, the reaction time is 1-10 seconds, and the weight ratio of the catalyst to the oil is 1-100; the feed weight ratio of the hydroupgraded light oil to the hydroupgraded heavy oil may be 0.01: 1-0.5: 1.

according to the invention, the catalytic cracking reactor may also be injected with steam, preferably in the form of atomized steam. The weight ratio of the injected steam to the hydroupgraded heavy oil (hydroupgraded light oil) may be 0.01 to 1, preferably 0.05 to 0.5.

In the catalytic cracking of the present invention, the spent catalyst and the reaction product are generally separated to obtain the spent catalyst and the reaction product, then the obtained reaction product is subjected to a subsequent separation system (for example, a cyclone separator) to separate fractions such as dry gas, liquefied gas, pyrolysis gasoline and pyrolysis diesel, then the dry gas and the liquefied gas are further separated by a gas separation device to obtain ethylene, propylene and the like, and the method for separating ethylene, propylene and the like from the reaction product is similar to the conventional technical method in the art, and the method is not limited in this respect, and is not described in detail herein.

According to the invention, the method of the invention also preferably comprises: regenerating the spent catalyst; and preferably at least a part of the catalytic cracking catalyst is regenerated, and for example, the whole of the catalyst may be regenerated catalyst.

According to the invention, the method of the invention also preferably comprises: the regenerated catalyst obtained by regeneration is stripped (generally by steam stripping) to remove impurities such as gas.

According to the invention, in the regeneration process, oxygen-containing gas is generally introduced from the bottom of the regenerator, the oxygen-containing gas can be air, for example, after being introduced into the regenerator, the catalyst to be generated is contacted with oxygen for scorching and regeneration, the gas-solid separation is carried out on the upper part of the regenerator on the flue gas generated after the scorching and regeneration of the catalyst, and the flue gas enters a subsequent energy recovery system.

According to the invention, the regeneration operation conditions of the spent catalyst can be as follows: the regeneration temperature is 550-750 ℃, preferably 600-730 ℃, and more preferably 650-700 ℃; the gas superficial linear velocity is 0.5 to 3 m/s, preferably 0.8 to 2.5 m/s, more preferably 1 to 2 m/s, and the average residence time of the spent catalyst is 0.6 to 3 minutes, preferably 0.8 to 2.5 minutes, more preferably 1 to 2 minutes.

Catalytic cracking catalysts are well known to those skilled in the art in accordance with the present invention, and conventional options may be employed in the present invention, for example, the first and second catalytic cracking catalysts may each independently comprise from 1 to 60 wt% zeolite, from 5 to 99 wt% inorganic oxide, and from 0 to 70 wt% clay, on a dry basis and based on the weight of the catalytic cracking catalyst; the zeolite is taken as an active component, preferably the zeolite is selected from medium-pore zeolite and/or large-pore zeolite, and the medium-pore zeolite accounts for 50-100 wt% of the total weight of the zeolite, preferably the medium-pore zeolite accounts for 70-100 wt% of the total weight of the zeolite, and the large-pore zeolite accounts for 0-50 wt% of the total weight of the zeolite, preferably the large-pore zeolite accounts for 0-30 wt% of the total weight of the zeolite. The medium pore size zeolite and the large pore size zeolite are defined by the convention in the art, i.e., the medium pore size zeolite has an average pore size of 0.5 to 0.6 nm and the large pore size zeolite has an average pore size of 0.7 to 1.0 nm. For example, the large pore zeolite may be selected from a mixture of one or more of the group of zeolites consisting of rare earth Y (rey), rare earth hydrogen Y (rehy), ultrastable Y obtained by different methods, high silicon Y. The intermediate pore size zeolite may be selected from zeolites having the MFI structure, such as ZSM-series zeolites and/or ZRP zeolites, which may also be modified with non-metallic elements such as phosphorus and/or transition metal elements such as iron, cobalt, nickel, as described in more detail in connection with ZRP, see U.S. Pat. No. 5,232,675, and the ZSM-series zeolites may be selected from one or more mixtures of ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48 and other zeolites of similar structure, as described in more detail in connection with ZSM-5, see U.S. Pat. No. 3,702,886. In the present invention, the inorganic oxide is preferably selected from silicon dioxide (SiO) as a binder₂) And/or aluminum oxide (Al)₂O₃). In the present invention, the clay is preferably selected from kaolin and/or halloysite as a matrix (i.e., carrier).

In one embodiment, when the process of the invention is carried out in a catalytic cracking reactor, it is generally carried out as follows: the catalytic cracking catalyst enters a pre-lifting section of a first reaction zone of a catalytic cracking reactor, flows upwards under the action of a pre-lifting medium, preheated hydro-upgrading heavy oil and atomized steam are injected into the first reaction zone together, and contact with a regenerated catalyst to perform catalytic cracking reaction and flow upwards at the same time, and enter a second reaction zone for continuous reaction, and the reacted material flow enters a cyclone separator through a reactor outlet; injecting the preheated hydro-upgrading light oil and atomized steam into a third reaction zone, contacting with a regenerated catalyst to perform catalytic cracking reaction and simultaneously flowing upwards, and allowing the reacted material flow to enter a cyclone separator through a reactor outlet; leading the separated reaction oil gas out of the device, and further separating to obtain ethylene, propylene, gasoline and other fractions; the separated spent catalyst enters a regenerator for coke burning regeneration, and the regenerated catalyst with recovered activity returns to the catalytic cracking reactor for recycling.

According to the invention, the conversion rate of the conversion reaction can be 30-70 wt%, the conversion rate of the conversion reaction is (weight of component with distillation range above 524 ℃ in inferior oil-weight of component with distillation range above 524 ℃ in conversion product)/weight of component with distillation range above 524 ℃ in inferior oil x 100 wt%; and/or the fraction of the heavy fraction may have a fraction of between 20 and 60 wt.% of components having a distillation range between 350 and 524 ℃. The invention can maintain the long-time operation of the system under the condition of reducing the outward throwing of the residue as much as possible and improving the resource utilization rate, the conversion reactor and the extraction separation unit are the key for determining whether the system can operate for a long time, the conversion rate of the conversion reactor is as high as possible under the condition of system stability, light fractions less than 350 ℃ in the first separation product entering the extraction separation unit are not too much, otherwise, the light fractions pollute the solvent, black oil is generated in the extraction separation process, heavy fractions with the distillation range of 350 ℃ and 524 ℃ are more, otherwise, the residue is not easy to flow and the conversion reaction is not easy to be carried out in the conversion reactor. The conversion rate of the conversion reaction is high, coke is easy to form, and the system running time is reduced, and the conversion rate is low, the outward throwing residue is easy to be too much, and the unit time modification efficiency is reduced.

The invention also provides a processing system of the inferior oil, which comprises a conversion reaction unit, an extraction separation unit and a catalytic cracking reactor, wherein the catalytic cracking reactor comprises a first reaction zone, a second reaction zone and a third reaction zone; the conversion reaction unit is provided with an inferior oil inlet, a hydrogen inlet, a light fraction outlet and a heavy fraction outlet, the extraction separation unit is provided with an extraction solvent inlet, a raw material inlet, a modified oil outlet and a residue outlet, the hydrogenation modification unit is provided with a hydrogen inlet, a raw material inlet, a gas product outlet, a hydrogenation modified light oil outlet and a hydrogenation modified heavy oil outlet, the first reaction zone is provided with a catalyst inlet, a raw material inlet and an oil agent outlet, the second reaction zone is provided with an oil agent inlet and an oil agent outlet, and the third reaction zone is provided with a catalyst inlet, a raw material inlet and an oil agent outlet; the heavy fraction outlet of the conversion reaction unit is communicated with the raw material inlet of the extraction separation unit, the modified oil outlet of the extraction separation unit is communicated with the raw material inlet of the hydro-modification unit, the hydro-modified heavy oil outlet of the hydro-modification unit is communicated with the raw material inlet of the first reaction zone, the oil agent outlet of the first reaction zone is communicated with the oil agent inlet of the second reaction zone, and the raw material inlet of the third reaction zone is communicated with the hydro-modified light oil outlet of the hydro-modification unit.

According to the invention, the catalytic cracking reactor can comprise three reaction zones, and can also comprise components such as oil separating equipment and a stripper, wherein the oil separating equipment can be a settler with a cyclone separator, and other conventional components can be arranged as required by a person skilled in the art, and the invention is not described in detail.

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

As shown in fig. 1, the poor oil is transferred to the shift reaction unit 30 through a line 31, a shift catalyst through a line 32, and hydrogen through a line 33 for shift reaction. The light fraction separated from the reaction product is led out through a pipeline 34, and the heavy fraction separated with the distillation range of more than 350 ℃ is conveyed to an extraction separation unit 36 through a pipeline 35 to be in countercurrent contact with an extraction solvent from a pipeline 37 for extraction separation, so that the modified oil and the residue are obtained. The residue is recycled via line 38 to the shift reaction unit 30 for continued shift reaction with the low grade oil. The modified oil enters a hydro-modification unit 40 through a pipeline 39 for hydro-modification to obtain hydro-modified light oil, hydro-modified heavy oil and a gas product, the obtained gas product is led out through a pipeline 41, and the hydro-modified heavy oil is sent into a first reaction zone 1 of the catalytic cracking reactor through a pipeline 16.

The pre-lifting medium enters the bottom of the first reaction zone 1 of the catalytic cracking reactor through a pipeline 14, the regenerated catalyst from a pipeline 12 enters the first reaction zone 1 after being regulated by a regeneration slide valve 13, and then moves upwards and quickly along the first reaction zone under the lifting action of the pre-lifting medium, the preheated hydro-upgrading heavy oil is injected into the first reaction zone 1 through a pipeline 16 and atomized steam from a pipeline 15, and is mixed with the existing material flow of the first reaction zone 1, the hydro-upgrading heavy oil generates catalytic cracking reaction on the hot catalyst, moves upwards and quickly, and enters a second reaction zone 26 to continue the catalytic cracking reaction; the pre-lifting medium enters the bottom of the third reaction zone 27 of the catalytic cracking reactor through a pipeline 29, the regenerated catalyst from a pipeline 28 enters the third reaction zone 27 and then moves upwards in an accelerated manner along the third reaction zone 27 under the lifting action of the pre-lifting medium, the preheated hydro-upgrading light oil is injected into the third reaction zone 27 through a pipeline 18 and atomized steam from a pipeline 17 and is mixed with the existing material flow of the third reaction zone 27, and the hydro-upgrading light oil is subjected to cracking reaction on the hot catalyst; the generated reaction product and the inactivated spent catalyst enter a cyclone separator 6 in a settler 3 to realize the separation of the spent catalyst and the reaction product, the reaction product enters an air collection chamber 7, and the fine powder of the catalyst returns to the settler. Spent catalyst in the settler flows to the stripping section 4 where it is contacted with steam from line 19. The reaction product stripped from the spent catalyst enters the gas collection chamber 7 after passing through the cyclone separator. The stripped spent catalyst enters the regenerator 2 after being regulated by a spent slide valve 9 of a spent inclined tube 8, air from a pipeline 21 enters the regenerator 2 after being distributed by an air distributor 22, coke on the spent catalyst in a dense bed layer at the bottom of the regenerator 2 is burned off to regenerate the inactivated spent catalyst, and flue gas enters a subsequent energy recovery system through an upper gas flue gas pipeline 25 of a cyclone separator 24. Wherein the pre-lifting medium may be dry gas, water vapor or a mixture thereof.

The regenerated catalyst enters a degassing tank 5 through a pipeline 10 communicated with a catalyst outlet of a regenerator 2, and is contacted with a stripping medium from a pipeline 23 at the bottom of the degassing tank 5 to remove flue gas carried by the regenerated catalyst, one part of the degassed regenerated catalyst is circulated to the bottom of a first reaction zone 1 through a pipeline 12, the circulation amount of the catalyst can be controlled through a regeneration slide valve 13, the other part of the degassed regenerated catalyst is circulated to the bottom of a third reaction zone 27 through a pipeline 28, gas in the degassing tank 5 returns to the regenerator 2 through a pipeline 11, and reaction products in a gas collection chamber 7 enter a subsequent separation system through a large oil-gas pipeline 20.

The following examples further illustrate the process but do not limit the invention.