CN113355132B

CN113355132B - Method for catalytic cracking of hydrogenated oil

Info

Publication number: CN113355132B
Application number: CN202010149337.4A
Authority: CN
Inventors: 任荣昊; 谢朝钢; 朱根权
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2020-03-04
Filing date: 2020-03-04
Publication date: 2023-02-21
Anticipated expiration: 2040-03-04
Also published as: CN113355132A

Abstract

The invention relates to a method for catalytically cracking hydrogenated oil, which comprises the following steps: spraying heavy oil into the riser reactor from a heavy oil nozzle at the bottom of the riser reactor, and contacting the heavy oil with a catalytic cracking catalyst from the lower part of the riser reactor to perform a first catalytic cracking reaction to obtain a first product and a first carbon deposition catalyst; injecting the hydrogenated oil and hydrogen-rich gas into the riser reactor from a long pipe feeding nozzle at the bottom of the riser reactor, and contacting the hydrogenated oil and the hydrogen-rich gas with the first product and the first carbon-deposited catalyst to perform a second catalytic cracking reaction to obtain a second product containing propylene and a second carbon-deposited catalyst; wherein the carbon deposit amount of the first carbon deposit catalyst is 0.1-0.5 wt% based on the total weight of the catalytic cracking catalyst; the long tube feed nozzle is located downstream of the heavy oil nozzle. The method can reduce the yield of dry gas while producing more propylene.

Description

Method for catalytic cracking of hydrogenated oil

Technical Field

The invention relates to the field of petrochemical industry, in particular to a catalytic cracking method of hydrogenation produced oil.

Background

Propylene is an important organic chemical raw material, and with the development of world economy, the demand for propylene is higher and higher. From 2006 to 2016, the production and consumption of propylene has increased year by year and has always presented a situation of supply and demand. By 2020, the demand for propylene in China is expected to reach 4000 ten thousand tons, with an annual average growth rate of about 4.7%. The production of chemical raw materials such as low-carbon olefin, aromatic hydrocarbon and the like from heavy raw materials through oil refining devices such as catalytic cracking and the like is a reasonable technical path for solving the problem of insufficient light raw oil in China, and the traditional catalytic hydrogenation and catalytic cracking combined process is generally used for improving the yield of fuel oil and improving the distribution and the quality of catalytic cracked products.

Patent US4619757 discloses a process for the production of olefins from heavy distillates by two-stage hydrotreatment. The method comprises a hydrotreating process and a thermal cracking process, wherein the hydrotreating process is carried out in two stages, the first stage is used for selectively removing polycyclic aromatic hydrocarbon, and the second stage is used for hydrodesulfurization and hydrodenitrogenation. In the first stage, a hydrotreating catalyst containing zeolite is used for treating the raw material with high polycyclic aromatic hydrocarbon content, and in the second stage, a hydrotreating catalyst containing no zeolite is used for treating the raw material with low polycyclic aromatic hydrocarbon content. The method has low hydrogen consumption, but low olefin yield.

Patent CN1119397C discloses a combined process of residual oil hydrotreating-catalytic cracking, in which residual oil and clarified oil enter a hydrotreating apparatus together, and hydrogenation reaction is performed in the presence of hydrogen and a hydrogenation catalyst; the hydrogenated residual oil obtained by the reaction enters a catalytic cracking device, the cracking reaction is carried out in the presence of a cracking catalyst, and the heavy cycle oil circulates in the catalytic cracking device; and separating the oil slurry obtained by the reaction by a separator to obtain clarified oil, and returning the clarified oil to the hydrogenation device. The method converts the catalytic cracking slurry oil into light oil products, improves the yield of gasoline and diesel oil, and reduces the yield of heavy oil, but the yield of propylene produced by the method is lower.

Patent CN109704903A discloses a method for producing more propylene and light aromatic hydrocarbon, which comprises that in a first riser reactor, heavy hydrocarbon oil is in contact reaction with a cracking catalyst to obtain a carbon deposition catalyst and a first oil-gas product; in a fluidized bed reactor, carrying out contact reaction on the hydrotreated light oil and a cracking catalyst to obtain a second oil gas product and a carbon deposit catalyst; in the second riser reactor, C4 olefin is in contact reaction with the regenerated cracking catalyst and the carbon deposit catalyst from the fluidized bed reactor to obtain the carbon deposit catalyst and a third oil-gas product. The method simultaneously improves the yield of the propylene and the light aromatic hydrocarbon.

Patent CN109666506A discloses a method for co-processing non-hydrotreated oil and hydrotreated oil. The method comprises the steps of firstly, spraying non-hydrogenated generated oil into a riser reactor from a heavy oil nozzle at the bottom of the riser reactor to perform catalytic cracking reaction to obtain a first reaction product and a semi-spent catalyst; and spraying the hydrogenated oil into the riser reactor from the upper part of the heavy oil nozzle to contact with the first reaction product and the semi-spent catalyst, and carrying out a second catalytic cracking reaction. The method carries out layered feeding on the hydrogenated oil and the non-hydrogenated oil, can adjust the hydrogen transfer activity of a reaction system, and improves the yield of the low-carbon olefin.

Disclosure of Invention

The invention aims to provide a method for catalytically cracking hydrogenated oil, which can improve the yield of propylene in products and reduce the content of dry gas.

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

(1) Injecting heavy oil into the riser reactor from a heavy oil nozzle at the bottom of the riser reactor to contact with a catalytic cracking catalyst from the bottom of the riser reactor to perform a first catalytic cracking reaction to obtain a first product and a first carbon deposition catalyst;

(2) Spraying hydrogenated oil and hydrogen-rich gas into the riser reactor from a long pipe feeding nozzle at the lower part of the riser reactor, and contacting the hydrogenated oil and the hydrogen-rich gas with the first product and the first carbon-deposited catalyst to perform a second catalytic cracking reaction to obtain a second carbon-deposited catalyst and a second product containing propylene;

wherein the carbon deposit amount of the first carbon deposit catalyst is 0.1 to 0.5 weight percent based on the total weight of the catalytic cracking catalyst; the long tube feed nozzle is located downstream of the heavy oil nozzle.

The carbon deposit amount of the first carbon deposit catalyst is 0.15 to 0.35 percent by weight based on the total weight of the catalytic cracking catalyst.

Optionally, in step (1), the conditions of the first catalytic cracking reaction include: the residence time of the heavy oil is 0.1-3 seconds, the temperature at the heavy oil nozzle is 600-700 ℃, and the pressure is 0.15-0.4MPa.

Optionally, the weight ratio of the catalytic cracking catalyst to the heavy oil is 30-300.

Optionally, the heavy oil is selected from one or more of atmospheric residue, vacuum residue, slurry oil and cycle oil.

Optionally, in step (2), the conditions of the second catalytic cracking reaction include: the outlet temperature of the riser reactor is 540-580 ℃, the retention time of the hydrogenation generated oil is 0.5-2.0 seconds, and the pressure is 0.15-0.4MPa.

Optionally, the weight ratio of the hydrogen-rich gas to the hydrogenated product oil is 0.00005 to 0.20.

Optionally, the hydrogenated oil feed temperature is 80 to 200 ℃.

Optionally, the hydrogen-rich gas is hydrogen or dry gas.

Optionally, the method further comprises: and feeding the second product and the second carbon-deposited catalyst into a fluidized bed reactor at the upper part of the riser reactor, and contacting the second product with a supplementary regenerant and the second carbon-deposited catalyst to perform a third catalytic cracking reaction.

Optionally, the temperature of the third catalytic cracking reaction is 500-650 ℃, and the weight hourly space velocity is 2-20 hours ^-1 The pressure is 0.15-0.4MPa.

Optionally, the supplemental regenerant constitutes from 10 to 30 wt% of the catalyst circulation volume in the riser reactor.

Alternatively, the catalytic cracking catalyst comprises, on a dry basis and based on the total weight of the catalytic cracking catalyst, from 1 to 60 wt% of a zeolite mixture, from 5 to 99 wt% of a refractory inorganic oxide, and from 0 to 70 wt% of a clay, wherein the zeolite mixture comprises from 1 to 90 wt% of a modified beta zeolite and from 10 to 99 wt% of a zeolite having an MFI structure, based on the total weight of the zeolite mixture.

Alternatively, the catalytic cracking catalyst contains on a dry basis and based on the total weight of the catalytic cracking catalyst, from 1 to 50 weight percent of the zeolite mixture, from 10 to 70 weight percent of the refractory inorganic oxide, and from 0 to 60 weight percent of the clay.

Through the technical scheme, the method adopts the catalytic cracking catalyst with specific carbon deposition amount, and the hydrogenation generated oil is subjected to catalytic cracking reaction under the hydrogen condition, so that the dehydrogenation reaction can be effectively inhibited, and the yield of dry gas can be reduced while the propylene is produced in a large amount.

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 is a schematic diagram of one embodiment of a catalytic cracking system for use in the process of the present invention.

Description of the reference numerals

1 riser reactor, 2 fluidized bed reactor and 3 steam stripper

4 settler 5 regenerator 6 regenerant delivery pipe

7 flow control valve 8 heavy oil nozzle 9 dilution steam nozzle

10 long tube feeding nozzle 11 outlet distributor 12 spent agent conveying pipe

13 flow control valve 14 make-up regenerant delivery pipe 15 flow control valve

Detailed Description

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.

The invention provides a catalytic cracking method of hydrogenated oil, which comprises the following steps:

(2) Injecting the hydrogenated oil and hydrogen-rich gas into the riser reactor from a long pipe feeding nozzle at the lower part of the riser reactor, and contacting the hydrogenated oil and the hydrogen-rich gas with the first product and the first carbon deposition catalyst to perform a second catalytic cracking reaction to obtain a second carbon deposition catalyst and a second product containing propylene;

wherein the carbon deposit amount of the first carbon deposit catalyst is 0.1-0.5 wt% based on the total weight of the catalytic cracking catalyst; the long tube feed nozzle is located downstream of the heavy oil nozzle.

The long pipe feed nozzle is positioned at the downstream of the heavy oil nozzle, namely, the heavy oil nozzle and the long pipe feed nozzle are sequentially arranged along the flowing direction of oil gas in the lifting pipe, and the long pipe feed nozzle is positioned above the heavy oil nozzle.

The inventor of the invention finds that because the hydrogenated oil has special properties, when the hydrogenated oil is contacted with a strong acid catalyst to perform catalytic cracking reaction, dehydrogenation reaction and hydrogen transfer reaction are easy to occur, the yield of propylene is low, and a large amount of dry gas is generated. Based on the problems, the method of the invention enables the hydrogenated oil to contact the carbon deposition catalyst with specific carbon deposition amount to carry out catalytic cracking reaction, and can effectively reduce hydrogen transfer reaction in the conversion process of the hydrogenated oil; and the second catalytic cracking reaction is carried out under the hydrogen condition, so that the dehydrogenation reaction in the conversion process of hydrogenation generated oil can be obviously reduced, the yield of dry gas is effectively reduced while more propylene is produced, and the service life of the catalyst is prolonged.

According to the present invention, the first carbon deposition catalyst may have a carbon deposition amount of 0.1 to 0.5 wt%, preferably 0.15 to 0.35 wt%, based on the total weight of the catalytic cracking catalyst. When the carbon deposition amount of the first carbon deposition catalyst is in the range, the first carbon deposition catalyst can more effectively reduce the hydrogen transfer reaction in the conversion process of hydrogenation generated oil, and further improve the yield of propylene in the product. The carbon deposit amount of the first carbon deposit catalyst can be measured by a thermogravimetric analysis method according to the RIPP 107-90 method.

According to the present invention, in step (1), the residence time of the heavy oil and the reaction temperature of the first catalytic cracking reaction may vary within a wide range, and in one embodiment, the conditions of the first catalytic cracking reaction include: the heavy oil has a residence time of 0.1-3 seconds, a temperature of 600-700 deg.C at the heavy oil nozzle, and a pressure of 0.15-0.4MPa. Preferably, the heavy oil has a residence time of 0.1 to 1.5 seconds, a temperature of 650 to 680 ℃ at the heavy oil nozzle, and a pressure of 0.18 to 0.35MPa. Wherein, the residence time of the heavy oil refers to the time from the heavy oil nozzle spraying the heavy oil into the riser reactor to the outlet of the long pipe feeding nozzle.

In one embodiment, the weight ratio of the amount of catalytic cracking catalyst to the amount of heavy oil used may be 30 to 300, preferably 60 to 200, in order to bring the amount of coke formation of the first coke forming catalyst within a suitable range according to the present invention.

According to the present invention, heavy oil is well known to those skilled in the art, and may be, for example, one or more selected from atmospheric residue, vacuum residue, slurry oil and recycle oil.

According to the present invention, the conditions of the catalytic cracking reaction have a significant influence on the product. In the step (2), the conditions of the second catalytic cracking reaction include: the outlet temperature of the riser reactor can be 540-580 ℃, the retention time of hydrogenation generated oil can be 0.5-2.0 seconds, and the pressure can be 0.15-0.4MPa; preferably, the outlet temperature of the riser reactor may be 550 to 570 ℃, the residence time of the hydrogenated product oil may be 1.2 to 1.8 seconds, and the pressure may be 0.18 to 0.35MPa. Wherein, pressure refers to absolute pressure, and the meaning of pressure in the following text is the same; the residence time of the hydrogenated oil refers to the time from the start of spraying the hydrogenated oil from the long-tube feed nozzle into the riser reactor to the outlet of the riser reactor. Under the conditions, the method is favorable for further improving the yield of propylene in the catalytic cracking reaction and reducing the yield of dry gas.

According to the present invention, the amount of the hydrogen-rich gas has an influence on the dehydrogenation reaction process, and in order to further reduce the dehydrogenation reaction in the conversion process of the hydrogenated oil, the weight ratio of the hydrogen-rich gas to the hydrogenated oil may be 0.00005 to 0.20, preferably 0.0001 to 0.1. Under the conditions, the hydrogen-rich gas and the hydrogenation generated oil are in proper proportion, so that the dehydrogenation reaction can be effectively reduced, and the yield of dry gas is effectively reduced.

According to the present invention, the first carbon-deposited catalyst may be entirely involved in the second catalytic cracking reaction in step (2).

According to the invention, the feed temperature of the hydrorefined oil may be from 80 to 200 ℃ and preferably from 100 to 150 ℃.

According to the invention, the hydrogen-rich gas may be hydrogen or a dry gas, preferably a dry gas.

According to the invention, the method may further comprise: and feeding the second product and the second carbon-deposited catalyst into a fluidized bed reactor at the upper part of the riser reactor, and contacting the second product with a supplementary regenerant and the second carbon-deposited catalyst to perform a third catalytic cracking reaction so as to further improve the yield of the propylene. The fluidized bed is well known to those skilled in the art, and may be, for example, a dense-phase fluidized bed reactor, and other types of fluidized bed reactors will not be described in detail herein.

In one embodiment, the second product and the second coke-forming catalyst leaving the riser reactor are introduced into the fluidized bed reactor from the bottom of the fluidized bed reactor, the post-reaction supplemental regenerant and the second coke-forming catalyst are also introduced from the bottom of the fluidized bed reactor, the reaction product of the third catalytic cracking reaction is introduced into a settler after being introduced from the top of the fluidized bed reactor, and the catalyst entrained therein is separated in the settler and introduced into a fractionation system; introducing the separated catalyst into a stripper, stripping the adsorbed hydrocarbon substances, and introducing into a regenerator for regeneration to obtain the regenerated catalytic cracking catalyst.

In one embodiment, a portion of the regenerated catalytic cracking catalyst is fed to the fluidized bed as a supplemental regenerant via a supplemental regenerant transfer line in fluid communication with the fluidized bed, and another portion of the regenerated catalytic cracking catalyst is fed to the bottom of the riser reactor as the catalytic cracking catalyst in step (1) via a regenerant transfer line in fluid communication with the riser reactor. The lift gas in the supplementary regenerant delivery line may be any gas known to those skilled in the art, and may be, for example, one or more of steam, dry gas, and a carbon four fraction, preferably a carbon four fraction.

According to the present invention, the make-up regenerant may constitute from 10 to 30 wt%, preferably from 15 to 25 wt%, of the catalyst circulation volume in the riser reactor to further increase the propylene yield. The catalyst circulation amount refers to the amount of fresh catalytic cracking catalyst entering the riser reactor along with the heavy oil for the first time, the fresh catalytic cracking catalyst is regenerated after reaction to obtain regenerated catalytic cracking catalyst, the regenerated catalytic cracking catalyst is continuously recycled, and fresh catalytic cracking catalyst is not supplemented to the riser reactor in the process.

According to the present invention, the temperature of the third catalytic cracking reaction may be 500 to 650 ℃, and the weight hourly space velocity may be 2 to 20 hours ^-1 The pressure can be 0.15-0.4MPa; preferably, the temperature of the third catalytic cracking reaction may be 550 to 600 ℃, and the weight hourly space velocity may be 10 to 15 hours ^-1 The pressure may be from 0.25 to 0.35MPa.

Catalytic cracking catalysts according to the present invention are well known to those skilled in the art. In one embodiment, the catalytic cracking catalyst comprises, on a dry basis and based on the total weight of the catalytic cracking catalyst, from 1 to 60 wt% of a zeolite mixture, from 5 to 99 wt% of a refractory inorganic oxide, and from 0 to 70 wt% of a clay, wherein the zeolite mixture comprises from 1 to 90 wt% of a modified beta zeolite and from 10 to 99 wt% of a zeolite having an MFI structure, based on the total weight of the zeolite mixture.

In a preferred embodiment, the catalytic cracking catalyst comprises 1 to 50 wt% of a zeolite mixture, 10 to 70 wt% of a refractory inorganic oxide, and 0 to 60 wt% of a clay, wherein the zeolite mixture comprises 1 to 75 wt% of a modified beta zeolite and 10 to 99 wt% of a zeolite having an MFI structure, based on the total weight of the zeolite mixture; preferably, the zeolite mixture contains 10 to 70 wt% of the modified beta zeolite and 30 to 90 wt% of the zeolite having the MFI structure, based on the total weight of the zeolite mixture. Modified beta zeolites are well known to those skilled in the art and may be, for example, phosphorus and a transition metal M modified beta zeolite. Wherein, the transition metal M can be one or more selected from Fe, co, ni and Cu, and is preferably Fe and/or Cu. Zeolites having the MFI structure are also well known to the person skilled in the art and may be, for example, high-silica zeolites having the Pentasil structure, preferably zeolites of the ZRP series and/or ZSM-5 zeolites. In one embodiment, the zeolite having the MFI structure is one or more of a rare earth-containing ZRP zeolite, a phosphorus-and rare earth-containing ZRP zeolite, a phosphorus-and alkaline earth-metal-containing ZRP zeolite, and a phosphorus-and transition-metal-containing ZRP zeolite. Beta zeolite and its preparationZeolites having the MFI structure are commercially available or can be prepared by methods well known in the art and will not be described further herein. The heat-resistant inorganic oxide may be selected from SiO ₂ And/or Al ₂ O ₃ . The clay may be various clays conventionally used in the art, such as kaolin and/or halloysite.

According to the present invention, modified beta zeolite can be prepared by methods well known to those skilled in the art. In one embodiment, phosphorus and a transition metal M are introduced during the synthesis of the zeolite beta; in another embodiment, the phosphorus and transition metal M are introduced after synthesis of the beta zeolite by steps such as ammonium exchange, phosphorus modification, transition metal M modification, and calcination.

In one embodiment, a diluent may be injected into the riser reactor during the catalytic cracking reaction to reduce the partial pressure of the hydrocarbon in accordance with the present invention. The diluent may be well known to those skilled in the art and may be, for example, one or more selected from the group consisting of steam, nitrogen and C1-C4 alkanes, preferably steam, and the weight ratio of steam to hydrogenated oil may be (0.01-2): 1, preferably (0.1-1): 1.

the invention also provides a catalytic cracking device for the catalytic cracking reaction, which comprises a riser reactor and a fluidized bed reactor connected with the riser reactor in series. The riser reactor is sequentially provided with a long pipe feeding nozzle, a heavy oil nozzle and a dilution steam nozzle from bottom to top. The riser reactor can be an equal diameter riser, an equal linear velocity riser or a variable diameter riser, and is preferably an equal diameter riser. The fluidized bed reactor may be a dense phase fluidized bed reactor, a bubble bed reactor, a turbulent bed reactor, or a fast bed reactor, preferably a turbulent bed reactor.

In a preferred embodiment, as shown in FIG. 1, heavy oil injection nozzle 8 injects heavy oil into the lower portion of riser reactor 1 to contact with the thermally regenerated catalyst via regenerator 5, regenerant delivery line 6 and flow control valve 7 to perform a first catalytic cracking reaction to obtain a first product and a first carbon deposit catalyst; the oil and hydrogen-rich gas generated by hydrogenation are sprayed from a long pipe feeding nozzle 10 (positioned at the downstream of a heavy oil nozzle) at the bottom of the riser reactor, and are sprayed out from the middle position of the riser reactor 1 to be mixed with the first product and the first carbon deposit catalyst to generate a second catalytic cracking reaction, so that a second product containing propylene and a second carbon deposit catalyst are obtained. The second product and the second carbon-deposited catalyst are continuously lifted, and are conveyed to the fluidized bed reactor 2 together with the dilution steam sprayed by the dilution steam nozzle 9 through the outlet distributor 11, and are contacted with the regenerated catalytic cracking catalyst conveyed through the supplementary regenerant conveying pipe 14 and the flow control valve 15 to generate a third catalytic cracking reaction. The regenerated catalytic cracking catalyst after reaction in the fluidized bed reactor 2 and the second carbon deposit catalyst after reaction enter a stripper 3 through the bottom of the fluidized bed reactor, enter a regenerator 5 for regeneration through a spent agent conveying pipe 12 and a flow control valve 13 after stripping, so that a product obtained in the fluidized bed reactor 2 enters a settler 4 from the top of the fluidized bed reactor 2, and the catalyst carried in the product is removed through a cyclone separator and enters a fractionation device for fractionation. The stripper 3 is in gas-solid communication with the fluidized bed reactor 2, and the amount of the catalyst in the fluidized bed reactor 2 can be directly controlled by adjusting a flow control valve 13 for discharging the spent catalyst to the regenerator 5 from the stripper 3 or controlling a flow control valve 15 for controlling the supplement agent conveyed to the fluidized bed reactor 2 by the regenerator 5, so as to control the weight hourly space velocity of the reaction in the fluidized bed reactor. The regenerated catalytic cracking catalyst in the regenerator 5 is introduced into the riser reactor 1 through the regenerant-transferring pipe 6.

The invention is further illustrated by the following examples, but is not to be construed as being limited thereto.

Example 1

The composition of the catalytic cracking catalyst used in this example was as follows: on a dry basis and based on the total weight of the catalytic cracking catalyst, 10 wt% beta zeolite, 20 wt% ZSM-5 zeolite, 45 wt% kaolin and 25 wt% aluminium binder.

The catalytic cracking catalyst is prepared by the following method: DASY zeolite (containing 2 wt% RE) ₂ O ₃ Products of the Medium petrochemical catalyst, qilu division) and ZSM-5 (Medium petrochemical catalyst)Products of the agent Qilu division, containing 1.1% by weight of RE ₂ O ₃ 1.2 percent by weight of phosphorus) is pulped with water to prepare slurry with the solid content of 30 percent by weight, kaolin (produced by Suzhou China kaolin company), pseudo-boehmite (produced by Shandong aluminum industry company) and water are mixed and pulped to prepare slurry with the solid content of 30 percent by weight, the two types of slurry are mixed and stirred for 30 minutes at the temperature of 50 ℃ to obtain catalyst slurry, and the catalyst slurry is sprayed and dried to obtain the catalytic cracking catalyst.

In the flow chart of this example, as shown in fig. 1, heavy oil (properties shown in table 1) is fed into a riser reactor 1 to contact with a regenerated catalytic cracking catalyst (equivalent to a fresh catalytic cracking catalyst) from a regenerator 5 to perform a first catalytic cracking reaction, and then a first product and a first carbon deposition catalyst are generated; adding hydrogenated oil (properties shown in Table 2) and dry gas from a long pipe feeding nozzle 10 at the bottom of the riser reactor, spraying out from the upper part of the riser reactor 1, mixing with the first product and the first carbon deposit catalyst, and carrying out a second catalytic cracking reaction to generate a second product and a second carbon deposit catalyst. The second product and the second carbon deposition catalyst are continuously lifted, and are conveyed to the fluidized bed reactor 2 (dense phase fluidized bed reactor) together with the dilution steam sprayed by the dilution steam nozzle 9, and are contacted with the supplementary regenerant conveyed by the supplementary regenerant conveying pipe 14 to generate a third catalytic cracking reaction. The spent catalyst after the reaction leaves from the bottom of the fluidized bed reactor 2 and enters a stripper 3, a product obtained by the third catalytic cracking reaction leaves from the top of the fluidized bed reactor 2 and enters a settler 4, and the carried catalyst is separated and enters a fractionation device; the reaction conditions and the reaction results are shown in Table 3.

The feeding temperature of the added hydrogenation generated oil is 100 ℃, the weight ratio of the dry gas to the hydrogenation generated oil is 0.0002, the carbon deposition amount of the first carbon deposition catalyst is 0.18 weight percent, and the supplementary re-agent accounts for 20 weight percent of the circulating amount of the riser catalyst.

TABLE 1

TABLE 2

Example 2

The procedure and catalytic cracking catalyst of this example were the same as in example 1, except that the weight ratio of dry gas to the hydrogenated oil was 0.0005. Other reaction conditions and reaction results are shown in Table 3.

Example 3

The procedure and catalytic cracking catalyst of this example were the same as in example 1, and the amount of soot of the first soot catalyst was 0.25% by weight. Other reaction conditions and reaction results are shown in Table 3.

Example 4

The procedure of this example is the same as example 1, and the catalytic cracking catalyst composition is as follows: the catalytic cracking catalyst contained 10 wt% beta zeolite, 30 wt% ZSM-5 zeolite, 40 wt% kaolin and 20 wt% aluminium binder on a dry basis and based on the total weight of the catalyst. Other reaction conditions and reaction results are shown in Table 3.

Example 5

The procedure and the catalytic cracking catalyst used in this example were the same as in example 1 except that the weight ratio of the catalytic cracking catalyst to the heavy oil was 350 and the amount of soot formed in the first soot forming catalyst was 0.11 wt%. Other reaction conditions and reaction results are shown in Table 3.

Example 6

The procedure and the catalyst used in this example were the same as in example 1 except that the weight ratio of the catalyst to the heavy oil was 15 and the amount of soot in the first soot catalyst was 0.41 wt%. Other reaction conditions and reaction results are shown in Table 4.

Example 7

The flow scheme and the catalytic cracking catalyst used in this example were the same as those of example 1 except that the weight ratio of dry gas to hydrogenated oil was 0.00001. Other reaction conditions and reaction results are shown in Table 4.

Example 8

The flow scheme and the catalytic cracking catalyst used in this example were the same as those of example 1 except that the weight ratio of dry gas to hydrogenated product oil was 0.3. Other reaction conditions and reaction results are shown in Table 4.

Example 9

The flow and the catalytic cracking catalyst used in this example were the same as those in example 1, and the feed temperature of the hydrogenated product oil in this example was 380 ℃, and the other reaction conditions and the reaction results are shown in Table 4.

Example 10

The procedure of this example is the same as example 1, and the composition of the catalytic cracking catalyst in this example is as follows: the catalytic cracking catalyst contained 10 wt% of Y zeolite, 20 wt% of ZSM-5 zeolite, 45 wt% of kaolin and 25 wt% of aluminum binder on a dry basis and based on the total weight of the catalytic cracking catalyst, and other reaction conditions and reaction results are shown in table 4.

Comparative example 1

The catalytic cracking catalyst used in this comparative example was the same as that used in example 1 except that the hydrogenated oil was fed to the riser reactor 1 and contacted with the regenerated catalyst from the regenerator 5 to conduct the first catalytic cracking reaction. The reacted oil-gas mixed product and the catalyst are continuously lifted, and are conveyed into the fluidized bed reactor 2 together with the dilution steam sprayed by the dilution steam nozzle 9, and are contacted with the regenerated catalytic cracking catalyst conveyed by the supplementary regenerant conveying pipe 14 to generate a second catalytic cracking reaction. The spent catalyst after the reaction is introduced to the bottom of the turbulent fluidized bed reactor 2, and leaves at the bottom of the fluidized bed reactor 2 and enters the stripper 3, the product obtained by the second catalytic cracking reaction leaves from the top of the fluidized bed reactor 2 and enters the settler 4, and the carried catalyst is separated and enters the fractionating device. Other reaction conditions and reaction results are shown in Table 5.

Comparative example 2

The procedure and catalytic cracking catalyst used in this comparative example were the same as in example 1 except that the hydrogenated oil was fed to the riser reactor through a long tubular feed nozzle without the addition of dry gas. Other reaction conditions and reaction results are shown in Table 5.

Comparative example 3

The procedure and the catalytic cracking catalyst used in this comparative example were the same as those in example 1 except that the hydrogenated oil and the dry gas were fed into the riser reactor 1 and contacted with the regenerated catalyst from the regenerator 5 to carry out the first catalytic cracking reaction. The reacted oil-gas mixed product and the catalyst are continuously lifted, and are conveyed to the fluidized bed reactor 2 together with the diluted steam sprayed by the diluted steam nozzle 9, and are contacted with the regenerated catalytic cracking catalyst conveyed by the supplementary regenerant conveying pipe 14 to generate a second catalytic cracking reaction. The spent catalyst after the reaction is introduced to the bottom of the fluidized bed reactor 2, leaves at the bottom of the fluidized bed reactor 2 and enters the stripper 3, and the product obtained by the second catalytic cracking reaction leaves from the top of the fluidized bed reactor 2 and enters the settler 4, and enters the fractionation device after the carried catalyst is separated out. Other reaction conditions and reaction results are shown in Table 5.

TABLE 3

TABLE 4

TABLE 5

Therefore, the method of the invention ensures that the catalytic cracking catalyst has specific carbon deposition amount, and the hydrogenated oil is subjected to catalytic cracking reaction under the hydrogen condition, so that the catalytic cracking reaction can produce more propylene and effectively reduce the yield of dry gas.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications all fall within the protection scope of the present invention.

It should be noted that, in the above embodiments, the various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, the present invention does not separately describe various possible combinations.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. A process for the catalytic cracking of a hydroproduced oil, the process comprising:

(1) Spraying heavy oil into the riser reactor from a heavy oil nozzle at the bottom of the riser reactor, and contacting the heavy oil with a catalytic cracking catalyst from the bottom of the riser reactor to perform a first catalytic cracking reaction to obtain a first product and a first carbon deposition catalyst;

wherein the carbon deposit amount of the first carbon deposit catalyst is 0.1 to 0.5 weight percent based on the total weight of the catalytic cracking catalyst; the long tube feed nozzle is located downstream of the heavy oil nozzle;

wherein in step (1), the conditions of the first catalytic cracking reaction comprise: the retention time of the heavy oil is 0.1-3 seconds, the temperature at the heavy oil nozzle is 600-700 ℃, and the pressure is 0.15-0.4MPa;

in the step (2), the conditions of the second catalytic cracking reaction include: the outlet temperature of the riser reactor is 540-580 ℃, the retention time of the hydrogenation generated oil is 0.5-2.0 seconds, and the pressure is 0.15-0.4MPa.

2. The process of claim 1, wherein the first carbon deposition catalyst has a carbon deposition amount of 0.15 to 0.35 wt.%, based on the total weight of the catalytic cracking catalyst.

3. The process according to claim 1, wherein the weight ratio of the catalytic cracking catalyst to the heavy oil is 30-300.

4. The process of claim 1, wherein the heavy oil is selected from one or more of atmospheric resid, vacuum resid, slurry oil, and cycle oil.

5. The method of claim 1, wherein the weight ratio of the hydrogen-rich gas to the hydrogenated product oil is 0.00005-0.20.

6. The process of claim 1, wherein the hydrogenated product oil has a feed temperature of 80-200 ℃.

7. The method of claim 1, wherein the hydrogen-rich gas is hydrogen or dry gas.

8. The method of claim 1, wherein the method further comprises: and feeding the second product and the second carbon-deposited catalyst into a fluidized bed reactor at the upper part of the riser reactor, and contacting the second product with a supplementary regenerant and the second carbon-deposited catalyst to perform a third catalytic cracking reaction.

9. The method of claim 8, wherein the third catalytic cracking reaction is carried out at a temperature of 500 to 650 ℃ and a weight hourly space velocity of 2 to 20 hours ^-1 The pressure is 0.15-0.4MPa.

10. The process of claim 8 or 9, wherein the supplemental regenerant comprises from 10 to 30 wt% of the catalyst circulation volume in the riser reactor.

11. The process of claim 1 wherein the catalytic cracking catalyst comprises, on a dry basis and based on the total weight of the catalytic cracking catalyst, from 1 to 60 wt% of a zeolite mixture comprising from 1 to 90 wt% of a modified beta zeolite and from 10 to 99 wt% of a zeolite having an MFI structure, from 5 to 99 wt% of a refractory inorganic oxide, and from 0 to 70 wt% of a clay, based on the total weight of the zeolite mixture.

12. The process of claim 11, wherein the catalytic cracking catalyst comprises 1 to 50 wt% of the zeolite mixture, 10 to 70 wt% of the refractory inorganic oxide, and 0 to 60 wt% of the clay, on a dry basis and based on the total weight of the catalytic cracking catalyst.