Fluidized catalytic conversion process for producing low carbon olefins from hydrocarbons

Abstract

A fluidized catalytic conversion process for producing low carbon olefins from hydrocarbons is disclosed, which includes the steps of: catalytically converting an olefin-rich feedstock in a first reaction area of ​​a fluidized catalytic conversion reactor; then contacting and reacting a heavy feedstock with a reaction stream from the first reaction area in a second reaction zone of the reactor; then separating an effluent from the reactor; and returning the resulting olefin-rich stream to the first reaction area for continued reaction. This process can improve the utilization rate of petrochemical resources and shows high yields and selectivities of ethylene, propylene and butenes.

Description

Detailed Description of the Invention

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to Chinese Patent Application No. 202110031551.4, filed on January 11, 2021, entitled "Catalytic Conversion Process for Preparing Ethylene, Propylene, and Butylene," and to Chinese Patent Application No. 202110245789.7, filed on March 5, 2021, entitled "Catalytic Conversion Process for Maximizing Ethylene Production with Propylene Co-production," and to Chinese Patent Application No. 202110296896.2, filed on March 19, 2021, entitled "Catalytic Conversion Process for Preparing Light Olefins," the contents of which are incorporated herein by reference in their entireties.

[0002] [Technical field] FIELD OF THE INVENTION This application relates to the technical field of fluidized catalytic conversion, and in particular to a fluidized catalytic conversion process for preparing light olefins from hydrocarbons.

[0003] [Background technology] Olefins with four or fewer carbon atoms are important chemical raw materials, and typical products include ethylene, propylene, and butylene. With the sustained and accelerated development of the economy, demand for light oil products and clean fuel oils from various industries is also rapidly increasing. Meanwhile, with the increase in oil field development, the available yield of conventional crude oil is gradually declining, and crude oil quality is becoming worse, more degraded, and heavier. Although China's light olefin production capacity is rapidly increasing, the domestic market demand for light olefins is currently unmet.

[0004] Ethylene-derived products include polyethylene, ethylene oxide, ethylene glycol, polyvinyl chloride, styrene, and vinyl acetate. Propylene-derived products include acrylonitrile, propylene oxide, and acetone. Butylene-derived products include butadiene, which is further used to produce methyl ethyl ketone, sec-butyl alcohol, butylene oxide, and butylene polymers and copolymers. Isobutylene-derived products include butyl rubber, polyisobutylene rubber, and various plastics. Therefore, demand for ethylene, propylene, and butylene, which are used in the production of various important organic chemicals, synthetic resins, synthetic rubber, and various fine chemicals, is increasing.

[0005] The petroleum route employs the traditional method of producing ethylene and propylene through steam cracking, which has a high demand for light hydrocarbons such as naphtha. It is expected that 70 million tons of light chemical oil will be needed by 2025. Domestic crude oil is typically heavy, and light chemical oil cannot meet the requirements for producing ethylene, propylene, and butylene feedstocks. Steam cracking feedstocks mainly include light hydrocarbons (e.g., ethane, propane, butane), naphtha, diesel, condensate, and hydrogenated tail oil, with naphtha accounting for over 50% by mass. Typical naphtha steam cracking yields an ethylene yield of approximately 29-34% and a propylene yield of 13-16%. The lower ethylene / propylene output ratio makes it difficult to meet the current demand for light olefins.

[0006] CN101092323A discloses a process for preparing ethylene and propylene from a mixture of C4-C8 olefins, which involves reacting at a reaction temperature of 400-600°C and an absolute pressure of 0.02-0.3 MPa, and recycling 30-90 wt% of the C4 fraction to the reactor after separation in a separator for further cracking. This process improves olefin conversion by recycling primarily the C4 fraction, and the resulting ethylene and propylene account for more than 62% of the total olefin feedstock. However, it suffers from a relatively low ethylene / propylene ratio and low reaction selectivity, which cannot be flexibly adjusted according to market demands.

[0007] CN101239878A discloses a method using a mixture rich in C4+ olefins as a raw material. The method involves a reaction temperature of 400-680°C, a reaction pressure of -0.09MPa-1.0MPa, and a reaction time of 0.1-50h. -1 The resulting product has an ethylene / propylene ratio of less than 0.41, and as the temperature increases, the ethylene / propylene ratio increases, resulting in increased production of hydrogen, methane, and ethane.

[0008] Non-petroleum routes primarily involve the production of light olefins, primarily ethylene and propylene, using oxygen-containing organic compounds (OOCs), typically methanol or dimethyl ether (DMEA), as feedstocks. The process for producing light olefins from Methanol or DMEA is characterized by rapid reaction speed, strong heat release, a low catalyst-to-alcohol ratio, and a long induction period. Rapid catalyst deactivation is a major challenge in the MTO process. Scientific and efficient solutions to the long induction period and susceptibility to catalyst deactivation in the MTO process remain a constant topic of discussion for many scientists and engineers.

[0009] Therefore, in the new stage of transforming oil refineries into integrated power plants of oil refining and chemical engineering, in the field of integrating multiple catalytic conversion reaction modes, there is an urgent need for a completely new catalytic conversion mode that can improve the yield of high-value light olefins, i.e., ethylene and propylene, and the selectivity of ethylene and propylene.

[0010] [Summary of the Invention] The object of the present application is to provide a fluidized catalytic conversion process for preparing light olefins (e.g., ethylene, propylene, and butylene) from hydrocarbons, which can significantly improve the yield and selectivity of ethylene, propylene, and butylene.

[0011] In order to achieve the above object, the present application provides a fluidized catalytic conversion process for preparing light olefins from hydrocarbons, the process comprising: 1) introducing an olefin-rich feedstock into a first reaction zone of a fluidized catalytic conversion reactor, wherein the olefin-rich feedstock contacts a catalytic conversion catalyst having a temperature of 650°C or greater and reacts under first catalytic conversion conditions, wherein the olefin-rich feedstock has an olefin content of 50 wt% or greater; 2) introducing a heavy feedstock into a second reaction zone downstream of the fluidized catalytic conversion reactor from the first reaction zone, wherein the heavy feedstock contacts the catalytic conversion catalyst from the first reaction zone after the reaction of step 1) and reacts under second catalytic conversion conditions; 3) separating the effluent from the fluidized catalytic conversion reactor to obtain a reaction product and a spent catalyst, and performing a first separation on the reaction product to obtain ethylene, propylene, butylene, a first catalytically cracked distillate oil, and a second catalytically cracked distillate oil; the first catalytically cracked distillate oil has an initial boiling point in the range of more than 20°C and less than 140°C, the second catalytically cracked distillate oil has a final boiling point in the range of more than 250°C and less than 550°C, and a cut point between the first catalytically cracked distillate oil and the second catalytically cracked distillate oil is in the range of 140°C to 250°C; 4) subjecting the first catalytically cracked distillate to a second separation to obtain an olefin-rich stream having a C5+ olefin content of at least 50 wt.%; and 5) recycling at least a portion of said olefin-rich stream to step 1) for further reaction; The first catalytic conversion condition is: a reaction temperature of 600 to 800°C, preferably 630 to 780°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (1-200):1, preferably a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (3-180):1; The second catalytic conversion condition is: a reaction temperature of 400 to 650°C, preferably 450 to 600°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (1-100):1, preferably a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (3-70):1.

[0012] Optionally, the method may further comprise one or more of the following steps 6), 7) and 2a): 6) contacting the second catalytically cracked distillate with a hydrogenation catalyst to react under hydrogenation conditions to obtain a hydrotreated catalytically cracked distillate, and recycling the hydrotreated catalytically cracked distillate to the fluidized catalytic conversion reactor for further reaction; 7) recycling at least a portion of the butylenes separated in step 3) upstream of the catalytic conversion reactor where the olefin-rich feedstock is introduced to contact the catalytic conversion catalyst to react under third catalytic conversion conditions; The third catalytic conversion condition is: a reaction temperature of 650 to 800°C, preferably 680 to 780°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa; a reaction time of 0.01 to 10 seconds, preferably 0.05 to 8 seconds; The weight ratio of the catalytic conversion catalyst to the butylene is (20-200):1, preferably (30-180):1; and 2a) introducing an oxygen-containing organic compound into a second reaction zone of the fluidized catalytic conversion reactor to contact with a catalytic conversion catalyst in the second reaction zone of the fluidized catalytic conversion reactor for reaction under fourth catalytic conversion conditions; The fourth contact conversion condition is: a reaction temperature of 300 to 550°C, preferably 400 to 530°C; a reaction pressure of 0.01 to 1 MPa, preferably 0.05 to 1 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; The weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock is (1-100):1, preferably the weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock is (3-50):1.

[0013] In the fluidized catalytic conversion process of the present application, an olefin-rich feedstock is subjected to catalytic cracking in the first reaction zone of a fluidized catalytic conversion reactor, and then a heavy feedstock is contacted with the mixed stream from the first reaction zone in the second reaction zone for catalytic cracking reaction. The reaction product is subjected to first and second separations, and the resulting olefin-rich stream can be used again for catalytic cracking. The olefin-containing fraction in the reaction product can be used to further produce light olefins, improving the utilization rate of petrochemical resources; in the present application, the heavy feedstock is introduced into the production process, realizing the use of heavy oil and reducing costs; the fluidized catalytic conversion process for producing light olefins of the present application shows higher yields and selectivities of ethylene, propylene, and butylene; the yields of benzene, toluene, and xylene are also improved.

[0014] Other features and advantages of the present application are explained in detail in the following detailed description.

[0015] [Brief description of the drawing] The drawings that form part of this specification are provided to aid in understanding the application and should not be considered limiting. The application may be read with reference to the drawings in combination with the following detailed description. In the drawings: FIG. 1 shows a schematic flow diagram of a preferred embodiment of the fluidized catalytic conversion process of the present application.

[0016] FIG. 2 shows a schematic flow diagram of another preferred embodiment of the fluidized catalytic conversion process of the present application.

[0017] FIG. 3 shows a schematic flow diagram of yet another preferred embodiment of the fluidized catalytic conversion process of the present application.

[0018] [Brief explanation of symbols] I. First reaction zone II. Second Reaction Zone III. Third Reaction Zone 101 Pipeline 102 Reactor 103 Pipeline 104 Pipeline 105 Pipeline 106 Pipeline 107 Exit Section 108 Cyclone Separator 109 Plenum Chamber 110 Stripping Section 111 Pipeline 112 Standpipe 113 Regenerator 115 Pipeline 116 Pipeline 117 Pipeline 118 Pipeline 119 Reactor Vapor Line 120 Product rectification column 121 Pipeline 122 Pipeline 123 Pipeline 124 Pipeline 125 Pipeline 126 Pipeline 127 Pipeline 128 Olefin separator 129 Pipeline 130 Pipeline 131 Hydrotreater 132 Pipeline 201 Pipeline 202 Reactor 203 Pipeline 204 Pipeline 205 Pipeline 206 Pipeline 207 Exit Section 208 Cyclone Separator 209 Plenum Chamber 210 Stripping Section 211 Pipeline 212 Standpipe 213 Regenerator 215 Pipeline 216 Pipeline 217 Pipeline 218 Pipeline 219 Reactor Vapor Line 220 Product rectification column 221 Pipeline 222 Pipeline 223 Pipeline 224 Pipeline 225 Pipeline 226 Pipeline 227 Pipeline 228 Olefin separator 229 Pipeline 230 Pipeline 231 Pipeline 232 Hydrotreater 233 Pipeline 301 Pipeline 302 Reactor 303 Pipeline 304 Pipeline 305 Pipeline 306 Pipeline 307 Pipeline 308 Exit Section 309 Cyclone Separator 310 Plenum Chamber 311 Stripping Section 312 Pipeline 313 Standpipe 314 Regenerator 315 Pipeline 316 Pipeline 317 Pipeline 318 Pipeline 319 Reactor Vapor Line 320 Product rectification column 321 Pipeline 322 Pipeline 323 Pipeline 324 Pipeline 325 Pipeline 326 Pipeline 327 Pipeline 328 Pipeline 329 Olefin Separator 330 Pipeline 331 Pipeline 332 Hydrotreater 333 Pipeline [Mode for Carrying Out the Invention] The present application is described in further detail below with reference to the drawings and specific embodiments thereof. It should be noted that the specific embodiments of the present application are provided for illustrative purposes only and are not intended to be limiting in any way.

[0019] Any specific numerical values, including the boundary points of a numerical range, described in the context of this application should not be limited to those exact values, but should be interpreted as including all values ​​close to the exact value, for example, all values ​​within ±5% of the exact value. Furthermore, with respect to any numerical range described herein, any combination can be made between the boundary points of the range, between each boundary point and any specific value within the range, or between any two specific values ​​within the range, to provide one or more new numerical ranges. Here, the new numerical ranges should also be considered to be specifically described in this application.

[0020] Unless otherwise specified, terms used herein have the same meaning as commonly understood by one of ordinary skill in the art; if a term is defined herein and that definition differs from the common understanding in the art, the definition provided herein shall prevail.

[0021] In the context of this application, the expression "C5+" means having at least 5 carbon atoms, for example, the term "C5+ olefins" refers to olefins having at least 5 carbon atoms, while the term "C5+ fraction" refers to a fraction whose compounds have at least 5 carbon atoms.

[0022] In the context of this application, in addition to the explicitly stated subject matter, any subject matter or unmentioned subject matter shall be deemed to be the same as that known in the art without any changes.Furthermore, any of the embodiments described herein can be freely combined with one or more different embodiments described herein, and the technical solutions or ideas thus obtained shall be deemed to be part of the original disclosure or original description of this application, and unless it is obvious to those skilled in the art that such combination is obviously unreasonable, said technical solutions or ideas shall not be deemed to be new matters not disclosed or anticipated herein.

[0023] All patent and non-patent literature cited herein, including but not limited to textbooks and journal articles, is hereby incorporated by reference in its entirety.

[0024] As mentioned above, the present application provides a fluidized catalytic conversion process for producing light olefins from hydrocarbons, the process comprising: 1) introducing an olefin-rich feedstock into a first reaction zone of a fluidized catalytic conversion reactor, wherein the olefin-rich feedstock is contacted for reaction with a catalytic conversion catalyst having a temperature of 650°C or more, and the olefin-rich feedstock has an olefin content of 50 wt% or more; 2) introducing a heavy feedstock into a second reaction zone downstream of the fluidized catalytic conversion reactor from the first reaction zone, wherein the heavy feedstock contacts for reaction with the catalytic conversion catalyst from the first reaction zone after the reaction of step 1); 3) separating the effluent from the fluidized catalytic conversion reactor to obtain a reaction product vapor and a spent catalyst, and performing a first separation on the reaction product vapor to obtain ethylene, propylene, butylene, a first catalytic cracked distillate oil, and a second catalytic cracked distillate oil; the first catalytic cracked distillate oil has an initial boiling point in the range of more than 20°C and less than 140°C, the second catalytic cracked distillate oil has a final boiling point in the range of more than 250°C and less than 550°C, and a cut point between the first catalytic cracked distillate oil and the second catalytic cracked distillate oil is in the range of 140°C to 250°C; 4) subjecting the first catalytically cracked distillate to a second separation to obtain an olefin-rich stream having a C5+ olefin content of at least 50 wt.%; and 5) recycling at least a portion of said olefin-rich stream to step 1) for further reaction.

[0025] The inventors of the present application have surprisingly found, through a large number of catalytic cracking tests on alkanes and olefins, that by reacting olefins and alkanes respectively under the same catalytic cracking conditions, the yield and selectivity of light olefins produced by the cracking of olefins are significantly better than those of alkanes; the difference in product distribution between the catalytic cracking of olefins and alkanes is also significant, thereby arriving at the technical solution of the present application.

[0026] In a preferred embodiment, the reaction of step 1) is carried out under first catalytic conversion conditions comprising: a reaction temperature of 600 to 800°C, preferably 630 to 780°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; A weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (1-200):1, preferably a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (3-180):1.

[0027] In a preferred embodiment, the reaction of step 2) is carried out under second catalytic conversion conditions comprising: a reaction temperature of 400 to 650°C, preferably 450 to 600°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (1-100):1, preferably a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (3-70):1.

[0028] In a preferred embodiment, the olefin-rich feedstock employed herein has an olefin content of 80 wt% or more, preferably 90 wt% or more; more preferably, the olefin-rich feedstock is a pure olefin feedstock. During research, the inventors of the present application have found that increasing the olefin content in the olefin-rich feedstock is beneficial to improving the yield and selectivity of light olefins in the product, and even better results can be obtained by using C5+ olefins.

[0029] In preferred embodiments, the olefins in the olefin-rich feedstock consist essentially of C5+ olefins, for example, at least 80%, at least 85%, at least 90%, or at least 95% of the olefins in the olefin-rich feedstock, more preferably 100% of the olefins are C5+ olefins.

[0030] In the present application, the olefin-rich feedstock may be derived from various sources, and is not particularly limited thereto. In some embodiments, the olefin-rich feedstock may be obtained solely from the stream containing C5+ olefins separated from the catalytic conversion product of heavy oil feedstock, that is, the olefin-rich feedstock may be the olefins recycled in the system; in other embodiments, the olefin-rich feedstock may contain an external olefin feedstock in addition to the above-mentioned stream containing C5+ olefins, and the amount of the external olefin feedstock is not particularly limited.

[0031] In some embodiments, the olefin-rich feedstock used in step 1) may be obtained from any one or more of the following sources: C5+ fractions produced by alkane dehydrogenation units, C5+ fractions produced by catalytic cracking units in refineries, C5+ fractions produced by steam cracking units in ethylene plants, and olefin-rich C5+ by-product fractions of the MTO (methanol to olefins) and MTP (methanol to propylene) processes. In a preferred embodiment, the alkane feedstock for the alkane dehydrogenation unit may be obtained from at least one of naphtha, aromatic raffinate, and / or other light hydrocarbons. In actual production, alkane products from other petrochemical plants may also be used.

[0032] In some embodiments, the olefin-rich feedstock used herein is obtained by contacting an alkane with a dehydrogenation catalyst in a dehydrogenation reactor under catalytic dehydrogenation conditions, wherein the dehydrogenation conditions used are a dehydrogenation reactor inlet temperature of 400-700° C., a dehydrogenation time of 500-5000 hours, -1 and a reaction pressure of 0.04 to 1.1 bar.

[0033] Preferably, the dehydrogenation catalyst comprises a support, an active component supported on the support, and a promoter; the support is present in an amount of 60 to 90 wt %, the active component is present in an amount of 8 to 35 wt %, and the promoter is present in an amount of 0.1 to 5 wt %, based on the total weight of the dehydrogenation catalyst.

[0034] More preferably, the support may be alumina containing a modifier; the content of the modifier may be 0.1 to 2 wt % based on the total weight of the dehydrogenation catalyst, and the modifier may be La and / or Ce; the active component may be platinum and / or chromium; and the promoter may be a composition of bismuth and an alkali metal component or a composition of bismuth and an alkaline earth metal component. Here, the molar ratio of bismuth to the active component is 1:(5 to 50), the molar ratio of bismuth to the alkali metal component is 1:(0.1 to 5), and the molar ratio of bismuth to the alkaline earth metal component is 1:(0.1 to 5). Particularly preferably, the alkali metal component may be one or more selected from Li, Na, and K; and the alkaline earth metal component may be one or more selected from Mg, Ca, and Ba.

[0035] In some preferred embodiments, the fluid catalytic conversion process of the present application further comprises the steps of: 6) The second catalytically cracked distillate oil is contacted with a hydrogenation catalyst to react under hydrogenation conditions to obtain a hydrotreated catalytically cracked distillate oil, and the hydrotreated catalytically cracked distillate oil is recycled to the fluidized catalytic conversion reactor for further reaction. In this embodiment, the reaction product of the catalytic gas oil is subjected to hydrotreatment and then introduced back into the fluidized catalytic conversion reactor for further reaction, thereby improving the utilization rate of the raw material and increasing the yields of ethylene, propylene, and butylene.

[0036] Preferably, the hydrocatalytically cracked distillate is recycled to the second reaction zone of the fluidized catalytic conversion reactor for further reaction. In this embodiment, the saturated hydrocarbons with a relatively high carbon number contained in the hydrocatalytically cracked distillate may be first cracked into C5-C9 olefins in the second reaction zone under relatively mild reaction conditions; then, in step 5), the obtained olefins are recycled to the first reaction zone of the reactor together with the olefin-rich stream, where they are cracked again at high temperature, thereby further increasing the ethylene yield.

[0037] According to the present application, the hydrogenation conditions in step 6) may be those commonly used in the art and are not strictly limited in this specification. In a more preferred embodiment, the reaction conditions of the second catalytic cracking distillate oil and the hydrogenation catalyst are a hydrogen partial pressure of 3.0 to 20.0 MPa, a reaction temperature of 300 to 450°C, a volume ratio of hydrogen to oil of 300 to 2000, and a reaction time of 0.1 to 3.0 h. -1 The volumetric space velocity may include

[0038] According to the present application, the hydrogenation catalyst used in step 6) may be one commonly used in the art, and is not strictly limited herein. For example, the hydrogenation catalyst may include a support, a metal component supported on the support, and any additives. Preferably, the hydrogenation catalyst includes 20 to 90 wt. % of the support, 10 to 80 wt. % of the supported metal, and 0 to 10 wt. % of the additive, based on the total weight of the hydrogenation catalyst. More preferably, the support is alumina and / or amorphous silica-alumina, the metal component is a Group VIB metal and / or a Group VIII metal, and the additive is at least one selected from fluorine, phosphorus, titanium, and platinum; even more preferably, the Group VIB metal is Mo and / or W, and the Group VIII metal is Co and / or Ni. Particularly preferably, the additive is present in an amount of 0 to 10 wt. %, the Group VIB metal is present in an amount of 12 to 39 wt. %, and the Group VIII metal is present in an amount of 1 to 9 wt. % based on the total weight of the hydrogenation catalyst.

[0039] In some preferred embodiments, the fluid catalytic conversion process of the present application further comprises the steps of: 7) recycling at least a portion of the butylenes separated in step 3) upstream of the catalytic conversion reactor where the olefin-rich feedstock is introduced to contact the catalytic conversion catalyst for reaction.

[0040] In this embodiment, the high-temperature catalytic conversion catalyst first contacts with butylene recycled to the reactor, then contacts with an olefin-rich feedstock, and then contacts with a heavy feedstock. The difficulty of cracking hydrocarbons increases with the decrease in their carbon atom number, and the energy required to crack butylene is relatively high. Therefore, the high-temperature catalytic conversion catalyst in this embodiment first contacts with butylene, and then contacts with a C5+ olefin-rich feedstock, so that butylene can be cracked at a higher temperature, improving butylene conversion and the selectivity of the products ethylene and propylene, reducing the production of by-products caused by the co-feeding of olefins, and achieving highly efficient utilization of resources.

[0041] Preferably, the reaction in step 7) is carried out under third catalytic conversion conditions including a reaction temperature of 650-800°C, a reaction pressure of 0.05-1 MPa, a reaction time of 0.01-10 seconds, and a weight ratio of the catalytic conversion catalyst to butylene of (20-200):1. More preferably, the third catalytic conversion conditions include a reaction temperature of 680-780°C, a reaction pressure of 0.1-0.8 MPa, a reaction time of 0.05-8 seconds, and a weight ratio of the catalytic conversion catalyst to butylene of (30-180):1.

[0042] In a preferred embodiment, the fluidized catalytic conversion process of the present application further comprises the steps of: 2a) introducing an oxygen-containing organic compound into the second reaction zone of said fluidized catalytic conversion reactor and contacting it with a catalytic conversion catalyst for reaction therein;

[0043] Preferably, the reaction in step 2a) is carried out under fourth catalytic conversion conditions including a reaction temperature of 300-550°C, a reaction pressure of 0.01-1 MPa, a reaction time of 0.01-100 seconds, and a weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock of (1-100):1. More preferably, the fourth catalytic conversion conditions include a reaction temperature of 400-530°C, a reaction pressure of 0.1-0.8 MPa, a reaction time of 0.1-80 seconds, and a weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock of (3-80):1.

[0044] In such embodiments of the present application, the oxygen-containing organic compound can be supplied alone or mixed with other feedstocks. For example, the oxygen-containing organic compound can be mixed with the heavy feedstock before being supplied to the second reaction zone of the fluidized catalytic conversion reactor, or the oxygen-containing organic compound can be supplied to the second reaction zone of the fluidized catalytic conversion reactor downstream from where the heavy feedstock is introduced.

[0045] Particularly preferably, the oxygen-containing organic compound comprises at least one of methanol, ethanol, dimethyl ether, methyl ethyl ether, and ethyl ether. For example, the oxygen-containing organic compound, such as methanol or dimethyl ether, may be obtained from coal-based or natural gas-based synthesis gas.

[0046] In a preferred embodiment, the fluidized catalytic conversion process of the present application further comprises the steps of: 8) The spent catalyst obtained by the separation in step 3) is regenerated by coke combustion to obtain a regenerated catalyst having a temperature of 650°C or higher, and then the regenerated catalyst is recycled upstream of the first reaction zone of the fluidized catalytic conversion reactor for use as a catalytic conversion catalyst.

[0047] In a preferred embodiment, the catalytic conversion catalyst used herein may comprise 1 to 50 wt. % molecular sieve, 5 to 99 wt. % inorganic oxide, and 0 to 70 wt. % clay, based on the total weight of the catalyst.

[0048] In a further preferred embodiment, a molecular sieve functions as the active component in the catalytic conversion catalyst, and the molecular sieve may be selected from macroporous molecular sieves, mesoporous molecular sieves, and microporous molecular sieves, or combinations thereof.

[0049] In some more preferred embodiments, the mesoporous molecular sieve may be a ZSM molecular sieve. The ZSM molecular sieve may be selected from, for example, ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-48, or a combination thereof; the microporous molecular sieve may be a SAPO molecular sieve, for example, SAPO-34, SAPO-11, SAPO-47, or a combination thereof, and / or may be a SSZ molecular sieve, for example, SSZ-13, SSZ-39, SSZ-62, or a combination thereof; the macroporous molecular sieve may be selected from REY molecular sieve, REHY molecular sieve, ultrastable Y molecular sieve, high-silica Y molecular sieve, beta molecular sieve, and other molecular sieves of similar structure, or a mixture thereof.

[0050] In a particularly preferred embodiment, the molecular sieve comprises 40% to 100% by weight, preferably 50% to 100% by weight, of mesoporous molecular sieves, 0% to 30% by weight, preferably 0% to 25% by weight, of microporous molecular sieves, and 0% to 30% by weight, preferably 0% to 25% by weight, of macroporous molecular sieves, based on the total weight of the molecular sieves.

[0051] In a further preferred embodiment, in the catalytic conversion catalyst, an inorganic oxide functions as a binder, preferably the inorganic oxide may be selected from silicon dioxide (SiO2) and / or aluminum oxide (Al2O3).

[0052] In a further preferred embodiment, clay functions as a matrix in the catalytic conversion catalyst, and preferably the clay may be selected from kaolin and / or halloysite.

[0053] In a more preferred embodiment, the catalytic conversion catalyst used in the present application may further contain a modifying element to further improve the catalytic performance of the catalytic conversion catalyst. For example, the catalytic conversion catalyst may contain 0.1 to 3 wt. % of the modifying element based on the weight of the catalyst; the modifying element may be one or more selected from Group VIII metals, Group IVA metals, Group V metals, and rare earth metals. In a more preferred embodiment, the modifying element may be one or more selected from phosphorus, iron, cobalt, and nickel.

[0054] According to the present application, the heavy feedstock used in step 2) may be that commonly used in the art and is not particularly limited herein. In a preferred embodiment, the heavy feedstock may be selected from petroleum hydrocarbons and / or mineral oils; the petroleum hydrocarbons may be selected from vacuum gas oil, atmospheric gas oil, coker gas oil, deasphalted oil, vacuum residue, atmospheric residue, and heavy aromatic raffinate, or a combination thereof; the mineral oil may be selected from coal liquid oil, oil sand oil, and shale oil, or a combination thereof.

[0055] According to the present application, a fluidized catalytic conversion reactor can include one reactor or multiple reactors connected in series and / or parallel.

[0056] In a preferred embodiment, the fluidized catalytic conversion reactor may be selected from a riser reactor, a fluidized bed reactor, an upward transfer line, a downward transfer line, or a combination of two or more thereof. The riser reactor may be an isodiameter riser reactor or a diameter-converting riser reactor. The fluidized bed reactor may be an isolinear velocity fluidized bed reactor or an isodiameter fluidized bed reactor. The diameter-converting riser reactor may be, for example, a riser reactor as described in Chinese Patent CN1078094C.

[0057] In a more preferred embodiment, the fluidized catalytic conversion reactor is a riser reactor, more preferably a diameter conversion riser reactor.

[0058] In a preferred embodiment, the olefin-rich stream separated in step 4) has an olefin content of 80 wt% or more, more preferably a C5+ olefin content of 80 wt% or more. The higher the olefin content in the olefin-rich stream, the better the purification effect and the better the resource utilization.

[0059] According to the present application, the first separation in step 3) can be carried out using a separation device commonly used in the art, such as a product fractionator.

[0060] In a preferred embodiment, the second separation in step 4) can be carried out using an olefin separator to produce an olefin-depleted stream and an olefin-rich stream. The second separation can increase the olefin content of the olefin-rich stream recycled to the fluidized catalytic conversion reactor, thereby further increasing the yield and selectivity of light olefins.

[0061] In some further preferred embodiments, the olefin-rich stream is further separated in an olefin separator to obtain a large olefin-rich stream and a small olefin-rich stream, and the cutoff point between the two streams can be, for example, in the range of 140° C. to 200° C. The small olefin-rich stream is recycled to the first reaction zone of the fluidized catalytic conversion reactor in step 5) for further reaction; the large olefin-rich stream is recycled to the second reaction zone of the fluidized catalytic conversion reactor for further reaction.

[0062] Referring to FIG. 1, in a preferred embodiment, the fluidized catalytic conversion process of the present application is carried out as follows: A prelift medium is introduced into the bottom of a fluidized catalytic conversion reactor (riser reactor) 102 via pipeline 101, a regenerated catalytic conversion catalyst from pipeline 117 moves upward along the fluidized catalytic conversion reactor 102 under the lifting action of the prelift medium, and an olefin-rich feedstock (having an olefin content of ≧50%) is injected into the bottom of the first reaction zone I of the reactor 102 via pipeline 103 together with atomized steam from pipeline 104. There, the olefin-rich feedstock comes into contact with a high-temperature catalyst having a temperature of 650° C. or higher to react, and moves further upward.

[0063] Heavy feedstock oil is injected into the lower center of the fluidized catalytic conversion reactor 102 via pipeline 105 along with atomized steam from pipeline 106, and mixed with the flow from the first reaction zone I in the second reaction zone II, where the heavy feedstock oil comes into contact with the high-temperature catalyst to react and move upward.

[0064] The resulting reaction product and deactivated spent catalyst are sent through outlet section 107 to a cyclone separator 108 in the separator, where the spent catalyst and reaction product are separated. The reaction product is sent to a plenum chamber 109, and the fine catalyst powder is returned to the separator through a dipleg. The spent catalyst in the separator is sent to a stripping section 110, where it is contacted with stripping steam from pipeline 111. The product steam removed from the spent catalyst passes through the cyclone separator and is then sent to the plenum chamber 109. The stripped spent catalyst is sent to a regenerator 113 through a standpipe 112, and main air is introduced into the regenerator through pipeline 116 to burn the coke on the spent catalyst and regenerate the deactivated spent catalyst. The exhaust gas is sent to an exhaust gas turbine through pipeline 115. The regenerated catalyst is sent to the reactor 102 through pipeline 117.

[0065] The reaction product (reaction product vapor) is sent through reactor vapor line 119 to the subsequent product fractionator 120. The separated hydrogen, methane, and ethane are withdrawn through pipeline 121. Ethylene is withdrawn through pipeline 122. Propylene is withdrawn through pipeline 123. Butylene is withdrawn through pipeline 124 and, optionally, recycled to the bottom of reactor 102 for further reaction. Propane and butane are withdrawn through pipeline 125. The first catalytically cracked distillate is sent through pipeline 126 to olefin separator 128. The separated olefin-depleted stream is withdrawn through pipeline 129. The olefin-rich stream is sent through pipeline 130 to the bottom of first reaction zone I for further reaction. The second catalytically cracked distillate is sent to the hydrotreater 131 through the pipeline 127, and light components and hydrocatalytically cracked distillate are obtained after hydrotreatment, and the light components are withdrawn through the pipeline 118, and the hydrocatalytically cracked distillate is withdrawn through the pipeline 132, and optionally recycled to the second reaction zone II for further reaction.

[0066] Referring to FIG. 2, in another preferred embodiment, the fluidized catalytic conversion process of the present application is carried out as follows: A prelift medium is introduced through pipeline 201 into the bottom of a fluidized catalytic conversion reactor (riser reactor) 202, a regenerated catalytic conversion catalyst from pipeline 217 moves upward along the fluidized catalytic conversion reactor 202 under the lifting action of the prelift medium, and an olefin-rich feedstock (having an olefin content of ≥ 50%) is injected into the bottom of the first reaction zone I of the reactor 202 through pipeline 203 together with atomized steam from pipeline 204. There, the olefin-rich feedstock comes into contact with the high-temperature catalyst having a temperature of 650°C or higher, reacts, and moves further upward.

[0067] Heavy feedstock oil is injected into the lower center of the fluidized catalytic conversion reactor 202 via pipeline 205 along with atomized steam from pipeline 206, and mixed with the stream from the first reaction zone I in the second reaction zone II, where the heavy feedstock oil comes into contact with the high-temperature catalyst, reacts, and moves upward.

[0068] The resulting reaction product and deactivated spent catalyst are sent through outlet section 207 to a cyclone separator 208 in the separator, where the spent catalyst and reaction product are separated. The reaction product is sent to a plenum chamber 209, and the fine catalyst powder is returned to the separator through a dipleg. The spent catalyst in the separator is sent to a stripping section 210, where it is contacted with stripping steam from pipeline 211. The product steam removed from the spent catalyst passes through the cyclone separator and is then sent to the plenum chamber 209. The stripped spent catalyst is sent to a regenerator 213 through a standpipe 212, and main air is introduced into the regenerator through pipeline 216 to burn the coke on the spent catalyst and regenerate the deactivated spent catalyst. The exhaust gas is sent to an exhaust gas turbine through pipeline 215. The regenerated catalyst is sent to the reactor 202 through pipeline 217.

[0069] The reaction product (reaction product vapor) is sent through reactor vapor line 219 to the subsequent product fractionator 220, and the separated hydrogen, methane, and ethane are withdrawn through pipeline 221. Ethylene is withdrawn through pipeline 222. Propylene is withdrawn through pipeline 223. Butylene is withdrawn through pipeline 224 and, optionally, recycled to the bottom of reactor 202 for further reaction. Propane and butanes are withdrawn through pipeline 225. The first catalytically cracked distillate is sent through pipeline 226 to olefin separator 228. The separated olefin-depleted stream is withdrawn through pipeline 229. The separated stream rich in small olefins is sent through pipeline 230 to first reaction zone I for further reaction. The separated stream rich in large olefins is sent through pipeline 231 to the middle section of reactor 202 for further reaction in third reaction zone III downstream of second reaction zone II. The second catalytically cracked distillate is sent to the hydrotreater 232 through pipeline 227. Light components and hydrocatalytically cracked distillate are obtained after hydrotreating. The light components are withdrawn through pipeline 218. The hydrocatalytically cracked distillate is withdrawn through pipeline 233 and, optionally, recycled to the second reaction zone II for further reaction.

[0070] Referring to FIG. 3, in yet another preferred embodiment, the fluidized catalytic conversion process of the present application is carried out as follows: A prelift medium is introduced into the bottom of the fluidized catalytic conversion reactor (riser reactor) 302 through pipeline 301, the regenerated catalytic conversion catalyst from pipeline 317 moves upward along the fluidized catalytic conversion reactor 302 under the lifting action of the prelift medium, and the olefin-rich feedstock (having an olefin content of ≧50%) is injected into the bottom of the first reaction zone I of the reactor 302 through pipeline 303 together with atomized steam from pipeline 304. There, the olefin-rich feedstock comes into contact with the high-temperature catalyst having a temperature of 650° C. or higher to react, and moves further upward.

[0071] Heavy feedstock oil is injected into the lower center of the fluidized catalytic conversion reactor 302 via pipeline 305 along with atomized steam from pipeline 306, and mixed with the flow from the first reaction zone I in the second reaction zone II, where the heavy feedstock oil comes into contact with the high-temperature catalyst to react and move upward.

[0072] Oxygen-containing organic compounds (such as methanol) are injected into the second reaction zone II via pipeline 307 downstream of where the heavy feedstock oil is injected and mixed with the internal flow, where the oxygen-containing organic compounds come into contact with the catalytic conversion catalyst, react, and travel upward.

[0073] The resulting reaction product and deactivated spent catalyst are sent through outlet section 308 to a cyclone separator 309 in the separator, where the spent catalyst and reaction product are separated. The reaction product is sent to a plenum chamber 310, and the fine catalyst powder is returned to the separator through a dipleg. The spent catalyst in the separator is sent to stripping section 311, where it is contacted with stripping steam from pipeline 312. Product steam removed from the spent catalyst passes through the cyclone separator and is then sent to plenum 310. The stripped spent catalyst is sent to regenerator 314 through standpipe 313, and main air is introduced into the regenerator through pipeline 316 to burn the coke on the spent catalyst and regenerate the deactivated spent catalyst. The exhaust gas is sent to the exhaust gas turbine via pipeline 315. The regenerated catalyst is sent to reactor 302 via pipeline 317.

[0074] The reaction product (reaction product vapor) is sent through reactor vapor line 319 to the subsequent product fractionator 320, the separated hydrogen, methane, and ethane are withdrawn through pipeline 321, ethylene is withdrawn through pipeline 322, propylene is withdrawn through pipeline 323, and butylene is withdrawn through pipeline 324, optionally recycled to the bottom of reactor 302 for further reaction, propane and butane are withdrawn through pipeline 325, and the separated unconverted oxygen-containing organic compounds are withdrawn through pipeline 326, optionally recycled to the second reaction zone II for further reaction; the first catalytic cracking distillate is introduced through pipeline 327 into olefin separator 329. The separated olefin-depleted stream is withdrawn through pipeline 331. The separated olefin-rich stream is introduced into the bottom of the first reaction zone I through pipeline 330 for further reaction; the second catalytically cracked distillate is sent to the hydrotreater 332 through pipeline 328, and light components and hydrocatalytically cracked distillate are obtained after hydrotreatment, the light components are withdrawn through pipeline 318, and the hydrocatalytically cracked distillate is sent to the bottom of the second reaction zone II through pipeline 333 for further reaction.

[0075] In particularly preferred embodiments, the present application provides the following technical solutions: A1, a catalytic conversion process for producing ethylene, propylene and butylene, comprising the steps of: (1) contacting an olefin-rich feedstock having an olefin content of 50 wt.% or more with a catalytic conversion catalyst having a temperature of 650°C or more in a first reaction zone of a catalytic conversion reactor under first catalytic conversion conditions; (2) contacting the stream from the first reaction zone with a heavy feedstock in a second reaction zone of the catalytic conversion reactor under second catalytic conversion conditions to obtain a reaction product vapor and spent catalyst; (3) performing a first separation on the reaction product vapor to separate ethylene, propylene, butylene, a first catalytically cracked distillate, and a second catalytically cracked distillate; the first catalytically cracked distillate has an initial boiling point in the range of more than 20°C and less than 140°C, the second catalytically cracked distillate has a final boiling point in the range of more than 250°C and less than 550°C, and the cut point between the first catalytically cracked distillate and the second catalytically cracked distillate is in the range of 140°C to 250°C; conducting a second separation of the first catalytically cracked distillate to separate an olefin-rich stream containing at least 50 wt.% C5+ olefins; and (4) recycling the olefin-rich stream to the catalytic conversion reactor for further reaction; A method comprising:

[0076] A2. The method according to item A1, further comprising: contacting the second catalytically cracked distillate with a hydrogenation catalyst for reaction under hydrogenation conditions to obtain a hydrogenated second catalytically cracked distillate, and recycling the hydrogenated second catalytically cracked distillate to the catalytic conversion reactor for further reaction.

[0077] A3. The method according to item A2, wherein the hydrogenated second catalytically cracked distillate oil is recycled to the second reaction zone of the catalytic conversion reactor for further reaction, and the olefin-rich stream is recycled to the first reaction zone of the catalytic conversion reactor for further reaction; the first reaction zone is upstream of the second reaction zone in the flow direction of the reaction stream.

[0078] A4. The method according to item A3, wherein the separation system comprises a product fractionator and an olefin separator, the method comprising: sending the reaction product vapor to the product fractionator to separate ethylene, propylene, butylene, a first catalytically cracked distillate, and a second catalytically cracked distillate; Sending the first catalytically cracked distillate to the olefin separator to separate a first olefin-containing stream and a second olefin-containing stream; a cutoff point between the first olefin-containing stream and the second olefin-containing stream is in the range of 140°C to 200°C; recycling the first olefin-containing stream to a first reaction zone of the catalytic conversion reactor for further reaction and recycling the second olefin-containing stream to a third reaction zone of the catalytic conversion reactor for further reaction; wherein the third reaction zone is located downstream of the second reaction zone in the flow direction of the reaction stream.

[0079] A5, the method according to any one of items A1 to A4, wherein the catalytic conversion reactor is a riser reactor, preferably a diameter conversion riser reactor.

[0080] A6. The method according to item A1, wherein the first catalytic conversion conditions are: a reaction temperature of 650 to 750°C, preferably 630 to 750°C, more preferably 630 to 720°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa, more preferably 0.2 to 0.5 MPa; a reaction time of 0.01 to 100 seconds, preferably a reaction time of 0.1 to 80 seconds, more preferably a reaction time of 0.2 to 70 seconds; a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (1-100):1, preferably a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (3-150):1, more preferably a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (4-120):1; The second catalytic conversion condition is: a reaction temperature of 400 to 650°C, preferably 450 to 600°C, more preferably 480 to 580°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa, more preferably 0.2 to 0.5 MPa; a reaction time of 0.01 to 100 seconds, preferably a reaction time of 0.1 to 80 seconds, more preferably a reaction time of 0.2 to 70 seconds; a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (1-100):1, preferably a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (3-70):1, more preferably a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (4-30):1.

[0081] A7, the method according to item A2, wherein the hydrogenation conditions are: a hydrogen partial pressure of 3.0 to 20.0 MPa, a reaction temperature of 300 to 450°C, a volume ratio of hydrogen to oil of 300 to 2000, and a reaction time of 0.1 to 3.0 h -1 The method includes a volumetric space velocity of

[0082] A8. The method according to item A1, further comprising: regenerating the spent catalyst by coke combustion to obtain a regenerated catalyst; and recycling the regenerated catalyst to the first reaction zone of the catalytic conversion reactor as the catalytic conversion catalyst.

[0083] A9. The method according to item A1, wherein the olefin-rich feedstock has an olefin content of 80 wt.% or more, preferably 90 wt.% or more, and is more preferably a pure olefin feedstock; the olefins in the olefin-rich feedstock are selected from C5+ olefins; The method, wherein the heavy oil is selected from petroleum hydrocarbons and / or mineral oils; the petroleum hydrocarbons are one or more selected from vacuum gas oil, atmospheric gas oil, coker gas oil, deasphalted oil, vacuum residue, atmospheric residue, and heavy aromatic raffinate; and the mineral oil is one or more selected from the group consisting of coal liquid oil, oil sands oil, and shale oil.

[0084] A10, the method according to item A1 or A9, wherein the olefin-rich feedstock is obtained from at least one of a C5+ fraction produced by an alkane dehydrogenation unit, a C5+ fraction produced by a catalytic cracking unit in a refinery, a C5+ fraction produced by a steam cracking unit in an ethylene plant, a C5+ olefin-rich by-product fraction of an MTO process, and a C5+ olefin-rich by-product fraction of an MTP process; Optionally, the alkane feedstock of the alkane dehydrogenation unit is obtained from at least one of naphtha, aromatic raffinate, and other light hydrocarbons.

[0085] A11, the method according to item A1, wherein the catalytic conversion catalyst comprises 1 to 50 wt% of a molecular sieve, 5 to 99 wt% of an inorganic oxide, and 0 to 70 wt% of a clay, based on the total weight of the catalytic conversion catalyst; the molecular sieve comprises one or more of a macroporous molecular sieve, a mesoporous molecular sieve, and a microporous molecular sieve; The catalytic conversion catalyst further comprises 0.1 to 3 wt % of a metal ion based on the total weight of the catalytic conversion catalyst, and the metal ion is one or more selected from the group consisting of Group VIII metals, Group IVA metals, and rare earth metals.

[0086] A12, the method according to item A2, wherein the hydrogenation catalyst comprises 20 to 90 wt % of a support, 10 to 80 wt % of a supported metal, and 0 to 10 wt % of an additive, based on the total weight of the hydrogenation catalyst; the support is alumina and / or amorphous silica-alumina, the additive is at least one selected from the group consisting of fluorine, phosphorus, titanium, and platinum, and the supported metal is a Group VIB metal and / or a Group VIII metal; Preferably, the Group VIB metal is Mo or / and W, and the Group VIII metal is Co or / and Ni.

[0087] A13. The method according to item A1, wherein the olefin-rich stream comprises at least 50 wt% olefins, preferably at least 80 wt% olefins.

[0088] B1. A catalytic conversion process for maximizing the production of ethylene with the co-production of propylene, comprising the steps of: S1, contacting a hydrocarbon oil feedstock having an olefin content of 50 wt% or more with a catalytic conversion catalyst having a temperature of 650°C or more, and conducting a first catalytic conversion reaction in a first reaction zone of a catalytic conversion reactor to obtain a first mixed stream; S2, contacting the first mixed stream with a heavy feedstock oil in a second reaction zone of the catalytic conversion reactor, and conducting a second catalytic conversion reaction to obtain a reaction stream and a spent catalyst; the second reaction zone is located downstream of the first reaction zone; S3, a step of performing a first separation on the reaction stream to obtain ethylene, propylene, butylene, a first catalytically cracked distillate oil, and a second catalytically cracked distillate oil; the first catalytically cracked distillate oil has an initial boiling point of more than 20°C and less than 140°C, the second catalytically cracked distillate oil has a final boiling point of more than 250°C and less than 550°C, and a cut point between the first catalytically cracked distillate oil and the second catalytically cracked distillate oil is in the range of 140°C to 250°C; conducting a second separation of the first catalytically cracked distillate to obtain an olefin-rich stream; and separately introducing the butylenes and the olefin-rich stream into the catalytic conversion reactor for further reaction.

[0089] B2. The method according to item B1, wherein in step S3, the butylene introduced into the catalytic conversion reactor for further reaction is contacted with the catalytic conversion catalyst before the olefin-rich stream.

[0090] B3. The method according to item B1, wherein the olefins in the olefin-rich stream are C4+ olefins; The olefin content of the olefin-rich stream is between 50% and 100% by weight.

[0091] B4. The method according to item B1, wherein the butylene and the olefin-rich stream are separately introduced into the first reaction zone of the catalytic conversion reactor for further reaction.

[0092] B5. The method according to item B1, wherein the catalytic conversion reactor further comprises an A reaction zone and a B reaction zone; the A reaction zone is located between the first reaction zone and the second reaction zone; and the B reaction zone is located downstream of the second reaction zone; The second separation comprises: separating a first olefin-rich stream and a second olefin-rich stream from the first catalytically cracked distillate; a cutoff point between the first stream and the second stream is between 140°C and 200°C; introducing said butylene into said first reaction zone for further reaction; introducing said first stream into said A reaction zone for further reaction; introducing said second stream into said B reaction zone for further reaction; method.

[0093] B6, the method according to item B1, comprising: regenerating the spent catalyst by coke combustion to obtain a regenerated catalyst; and The method further comprises preheating the regenerated catalyst and then recycling it to the catalytic conversion reactor.

[0094] B7. The method according to item B1, comprising: hydrotreating the second catalytically cracked distillate to obtain a hydrogenated product, and separating the hydrotreated catalytically cracked distillate from the hydrogenated product; The method further comprises introducing the hydrocatalytically cracked distillate into the second reaction zone for further reaction.

[0095] B8. The method according to item B7, The hydrotreating conditions are: hydrogen partial pressure of 3.0 to 20.0 MPa, reaction temperature of 300 to 450°C, volume ratio of hydrogen to oil of 300 to 2000, and hydrotreating time of 0.1 to 3.0 h -1 The method includes a volumetric space velocity of

[0096] B9. The method according to item B1, wherein the catalytic conversion reactor is one selected from a riser reactor, a constant linear velocity fluidized bed, a constant diameter fluidized bed, an upward transfer line, and a downward transfer line, or a combination of two of them connected in series; The method wherein said riser reactor is preferably a diameter conversion riser reactor.

[0097] B10, the method according to item B1, wherein the first catalytic conversion conditions include: a reaction temperature of 600 to 800°C, a reaction pressure of 0.05 to 1 MPa, a reaction time of 0.01 to 100 s, and a weight ratio of the catalytic conversion catalyst to the hydrocarbon oil feedstock of (1 to 200):1; the second catalytic conversion conditions include: a reaction temperature of 400 to 650°C, a reaction pressure of 0.05 to 1 MPa, a reaction time of 0.01 to 100 seconds, and a weight ratio of the catalytic conversion catalyst to the heavy feedstock oil of (1 to 100):1; Preferably, the first catalytic conversion conditions include: a reaction temperature of 630-780°C, a reaction pressure of 0.1-0.8 MPa, a reaction time of 0.1-80 seconds, and a weight ratio of the catalytic conversion catalyst to the hydrocarbon oil feedstock of (3-180):1; The second catalytic conversion conditions include a reaction temperature of 450 to 600°C, a reaction pressure of 0.1 to 0.8 MPa, a reaction time of 0.1 to 80 seconds, and a weight ratio of the catalytic conversion catalyst to the heavy feedstock oil of (3 to 70):1; method.

[0098] B11. The method according to item B1, The conditions for further reaction of the butylene introduced into the catalytic reactor include: a reaction temperature of 650-800°C, a reaction pressure of 0.05-1 MPa, a reaction time of 0.01-10 seconds, and a weight ratio of the catalytic conversion catalyst to the butylene of (20-200):1; Preferably, the conditions include a reaction temperature of 680-780°C, a reaction pressure of 0.1-0.8 MPa, a reaction time of 0.05-8 seconds, and a weight ratio of the catalytic conversion catalyst to the butylene of (30-180):1.

[0099] B12. The method according to item B1, wherein the hydrocarbon oil feedstock has an olefin content of 80 wt.% or more, preferably 90 wt.% or more; more preferably, the hydrocarbon oil feedstock is a pure olefin feedstock; The heavy feedstock oil is a petroleum hydrocarbon and / or a mineral oil; the petroleum hydrocarbon is at least one selected from the group consisting of vacuum gas oil, atmospheric gas oil, coker gas oil, deasphalted oil, vacuum residue, atmospheric residue, and heavy aromatic raffinate; and the mineral oil is at least one selected from the group consisting of coal liquid oil, oil sands oil, and shale oil. method.

[0100] B13, the method according to item B1 or B12, wherein the olefins in the hydrocarbon oil feedstock are obtained from a C4+ fraction produced by dehydrogenation of an alkane feedstock, a C4+ fraction produced by a catalytic cracking unit in a refinery, a C4+ fraction produced by a steam cracking unit in an ethylene plant, a C4+ olefin-rich by-product fraction of an MTO process, and a C4+ olefin-rich by-product fraction of an MTP process; The process wherein the alkane feedstock is at least one selected from the group consisting of naphtha, aromatic raffinate, and light hydrocarbons.

[0101] B14. The method according to item B1, wherein the catalytic conversion catalyst comprises, based on the weight of the catalytic conversion catalyst, 1 to 50 wt. % of a molecular sieve, 5 to 99 wt. % of an inorganic oxide, and 0 to 70 wt. % of a clay; the molecular sieve comprises one or more of a macroporous molecular sieve, a mesoporous molecular sieve, and a microporous molecular sieve; The catalytic conversion catalyst further comprises 0.1 to 3 wt % of a reforming element based on the weight of the catalytic conversion catalyst, and the reforming element is one or more selected from the group consisting of Group VIII metals, Group IVA metals, and rare earth metals.

[0102] C1. A catalytic conversion process for producing light olefins, comprising the steps of: (1) contacting an olefin-rich feedstock with a catalytic conversion catalyst having a temperature of 650°C or greater in a first reaction zone of a catalytic conversion reactor, and conducting a first catalytic conversion reaction under first catalytic conversion conditions to obtain a first mixed stream; the olefin-rich feedstock having an olefin content of 50 wt% or greater; (2) contacting the first mixed stream from the first reaction zone with a heavy feedstock and an oxygen-containing organic compound feedstock in a second reaction zone of the catalytic conversion reactor, and conducting a second catalytic conversion reaction under second catalytic conversion conditions to obtain a reaction product vapor and spent catalyst; (3) performing a first separation on the reaction product vapor to separate ethylene, propylene, butylene, the oxygen-containing organic compounds, a first catalytically cracked distillate oil, and a second catalytically cracked distillate oil; the first catalytically cracked distillate oil has an initial boiling point greater than 20°C and less than 140°C, the second catalytically cracked distillate oil has a final boiling point greater than 250°C and less than 550°C, and a cutoff point between the first catalytically cracked distillate oil and the second catalytically cracked distillate oil is in the range of 140°C to 250°C; conducting a second separation of said first catalytically cracked distillate to separate an olefin-rich stream; (4) recycling the olefin-rich stream to the catalytic conversion reactor for further reaction.

[0103] C2. The method of claim C1, further comprising: sending the reaction product vapor to a product fractionator for a first separation and separating ethylene, propylene, butylene, the oxygen-containing organic compounds, the first catalytically cracked distillate, and the second catalytically cracked distillate; sending the first catalytically cracked distillate to an olefin separator for second separation and separating the olefin-rich stream; recycling the olefin-rich stream to the first reaction zone of the catalytic conversion reactor for further reaction; A method comprising:

[0104] C3, the method of item C1, comprising: passing the reaction product vapor to a product fractionator for a first separation and separating ethylene, propylene, butylene, the oxygen-containing organic compounds, the first catalytically cracked distillate, and the second catalytically cracked distillate; sending the first catalytically cracked distillate to an olefin separator for third separation and separating a large olefin stream from a small olefin stream; recycling the small olefin stream as the olefin-rich stream to the first reaction zone of the catalytic conversion reactor for further reaction; and recycling the large olefin stream to the second reaction zone of the catalytic conversion reactor for further reaction.

[0105] C4. The method according to any one of Items C1 to C3, further comprising: recycling the separated butylene to the first reaction zone of the catalytic conversion reactor for further reaction; preferably, contacting the butylene recycled to the catalytic conversion reactor with the catalytic conversion catalyst prior to the olefin-rich stream for further reaction.

[0106] C5. The method according to item C4, wherein the conditions for further reaction of the butylene recycled to the catalytic reactor include: a reaction temperature of 650 to 800°C, a reaction pressure of 0.05 to 1 MPa, a reaction time of 0.01 to 10 seconds, and a weight ratio of the catalytic conversion catalyst to the recycled butylene of (20 to 200):1; Preferably, the conditions include a reaction temperature of 680-780°C, a reaction pressure of 0.1-0.8 MPa, a reaction time of 0.05-8 seconds, and a weight ratio of the catalytic conversion catalyst to the recycled butylene of (30-180):1.

[0107] C6. The method of claim C1, wherein the first catalytic conversion conditions include: a reaction temperature of 600 to 800°C, preferably 630 to 780°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; A weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (1-200):1, preferably a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (3-180):1.

[0108] C7, the method according to item C1 or C6, wherein the second catalytic conversion conditions include: a reaction temperature of 300 to 650°C, preferably 400 to 600°C; a reaction pressure of 0.01 to 1 MPa, preferably 0.05 to 1 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (1 to 100):1, preferably a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (3 to 70):1; a weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock of (1 to 100):1, preferably a weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock of (3 to 50):1; The reaction temperature of the first catalytic conversion reaction is 30 to 380° C. higher than the reaction temperature of the second catalytic conversion reaction.

[0109] The method according to C8, C1 or C6, wherein the second reaction zone is divided into an upstream portion and a downstream portion along the flow direction of the reaction stream, the upstream portion being bounded by the supply position of the oxygen-containing organic compound feedstock, and the downstream portion of the second reaction zone is located downstream of the supply position of the oxygen-containing organic compound feedstock; the method further comprises the steps of: contacting the first mixed stream from the first reaction zone with the heavy feedstock in an upstream portion of the second reaction zone and conducting a catalytic conversion reaction to obtain a second mixed stream; then contacting the second mixed stream with the oxygen-containing organic compound feedstock in the downstream portion of the second reaction zone and conducting a catalytic conversion reaction to obtain the reaction product vapor and the spent catalyst.

[0110] C9. The method according to item C8, wherein the catalytic conversion conditions of the heavy feedstock and the first mixed stream in the upstream portion of the second reaction zone include: a reaction temperature of 400 to 650°C, preferably 450 to 600°C; a reaction pressure of 0.05 to 1 MPa, preferably 0.1 to 0.8 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (1-100):1, preferably a weight ratio of the catalytic conversion catalyst to the heavy feedstock of (3-70):1; Catalytic conversion conditions for the oxygen-containing organic compound feedstock and the second combined stream in the downstream portion of the second reaction zone include: a reaction temperature of 300 to 550°C, preferably 400 to 530°C; a reaction pressure of 0.01 to 1 MPa, preferably 0.05 to 1 MPa; a reaction time of 0.01 to 100 seconds, preferably 0.1 to 80 seconds; the reaction temperature in the upstream portion of the second reaction zone is 0 to 200°C higher, preferably 10 to 190°C higher, than the reaction temperature in the downstream portion of the second reaction zone; a weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock of (1-100):1, preferably a weight ratio of the catalytic conversion catalyst to the oxygen-containing organic compound feedstock of (3-50):1.

[0111] C10. The method of item C1, further comprising: recycling the separated oxygen-containing organic compounds to the second reaction zone of the catalytic conversion reactor for further reaction.

[0112] C11, the method according to any one of Items C1 to C10, wherein the catalytic conversion reactor is a riser reactor, preferably a diameter conversion riser reactor.

[0113] C12. The method according to item C1, further comprising: regenerating the spent catalyst by coke combustion to obtain a regenerated catalyst; and recycling the regenerated catalyst to the first reaction zone of the catalytic conversion reactor as the catalytic conversion catalyst.

[0114] C13. The method according to item C1, wherein the olefin-rich feedstock has an olefin content of 80 wt.% or more, preferably 90 wt.% or more, and is more preferably a pure olefin feedstock; The heavy oil is selected from petroleum hydrocarbons and / or mineral oils; the petroleum hydrocarbons are one or more selected from vacuum gas oil, atmospheric gas oil, coker gas oil, deasphalted oil, vacuum residue, atmospheric residue, and heavy aromatic raffinate; the mineral oil is one or more selected from the group consisting of coal liquids, oil sands oil, and shale oil; Optionally, the oxygen-containing organic compound feedstock comprises at least one of methanol, ethanol, dimethyl ether, methyl ethyl ether, and diethyl ether.

[0115] C14, the method according to item C1 or C13, wherein the olefin-rich feedstock is obtained from at least one of a C5+ fraction produced by an alkane dehydrogenation unit, a C5+ fraction produced by a catalytic cracking unit in a refinery, a C5+ fraction produced by a steam cracking unit in an ethylene plant, a C5+ olefin-rich by-product fraction of an MTO process, and a C5+ olefin-rich by-product fraction of an MTP process; Optionally, the alkane feedstock of the alkane dehydrogenation unit is obtained from at least one of naphtha, aromatic raffinate, and other light hydrocarbons.

[0116] C15. The method according to item C1, wherein the catalytic conversion catalyst comprises 1 to 50 wt. % of a molecular sieve, 5 to 99 wt. % of an inorganic oxide, and 0 to 70 wt. % of a clay, based on the total weight of the catalytic conversion catalyst; the molecular sieve comprises one or more of a macroporous molecular sieve, a mesoporous molecular sieve, and a microporous molecular sieve; The catalytic conversion catalyst further comprises 0.1 to 3 wt % of a metal ion based on the total weight of the catalytic conversion catalyst, and the metal ion is one or more selected from the group consisting of Group VIII metals, Group IVA metals, and rare earth metals.

[0117] C16. The method according to item C1, comprising contacting the second catalytically cracked distillate with a hydrogenation catalyst for reaction under hydrogenation conditions to obtain a hydrogenated second catalytically cracked distillate, and recycling the hydrogenated second catalytically cracked distillate to the catalytic conversion reactor for further reaction; The hydrogenation conditions are: hydrogen partial pressure of 3.0 to 20.0 MPa, reaction temperature of 300 to 450°C, volume ratio of hydrogen to oil of 300 to 2000, and time of 0.1 to 3.0 h-1 wherein the hydrogenation catalyst comprises 20 to 90 wt % of a support, 10 to 80 wt % of a supported metal, and 0 to 10 wt % of an additive, based on the total weight of the hydrogenation catalyst; wherein the support is alumina and / or amorphous silica-alumina, the additive is one or more selected from the group consisting of fluorine, phosphorus, titanium, and platinum, and the supported metal is a Group VIB metal and / or a Group VIII metal; Preferably, the Group VIB metal is Mo or / and W, and the Group VIII metal is Co or / and Ni.

[0118] C17. The method according to item C1, wherein the olefins in the olefin-rich stream are C5+ olefins; The process wherein said olefin-rich stream has a C5+ olefin content of 50 wt% or more, preferably 80 wt% or more.

[0119] [Example] The present invention will now be described in more detail with reference to the following examples, in which all feedstocks used are commercially available.

[0120] (Feedstock and Catalyst) The feedstocks I and II used in the following examples are heavy feedstock oils, namely, heavy oil I and heavy oil II, respectively, and their properties are shown in Tables 1-1 and 1-2 below.

[0121] [Table 1]

[0122] [Table 2]

[0123] The preparation or source of the various catalysts used in the following examples and comparative examples is as follows: 1) Catalyst i: Prepared as follows: 969 g of halloysite (China Kaolin Clay, 73% solids) was slurried in 4300 g of deionized water, and 781 g of pseudoboehmite (CHALCO Shandong, 64% solids) and 144 ml of hydrochloric acid (30% concentration, specific gravity 1.56) were added and stirred uniformly. The mixture was then left to stand and aged at 60 °C for 1 hour while maintaining the pH at 2-4. After cooling to room temperature, 5000 g of a prepared slurry containing 1600 g of mesoporous ZSM-5 molecular sieves and macroporous Y molecular sieves (Sinopec Catalyst, Qilu Branch) was added, resulting in a 9:1 weight ratio of mesoporous ZSM-5 molecular sieves to macroporous Y molecular sieves. The mixture was then stirred uniformly, spray-dried, and washed to remove free Na+ to obtain the catalyst. The resulting catalyst was then aged at 800 °C with 100% steam. The aged catalyst is designated catalyst i, and its properties are shown in Table 2.

[0124] 2) Catalyst ii: It is an industrial product available from Sinopec Catalyst Co., Ltd., Qilu Branch, under the trade name CEP-1, and its properties are shown in Table 2.

[0125] 3) Catalyst iii: This catalyst is an industrial product available from Sinopec Catalyst Co., Ltd., Qilu Branch, under the trade name CHP-1, and its properties are shown in Table 2.

[0126] 4) Catalyst iv: Prepared as follows: Ammonium metatungstate ((NH4)2W4O 13 Nickel nitrate (Ni(NO3)2·18H2O, chemically pure) and nickel nitrate (Ni(NO3)2·18H2O, chemically pure) were weighed and mixed with water to obtain 200 ml of solution. The solution was added to 50 g of alumina support and impregnated at room temperature for 3 hours. During the impregnation, the impregnated solution was treated with ultrasound for 30 minutes, cooled, filtered, and dried in a microwave oven for approximately 15 minutes. The catalyst contained the following components: 30.0 wt. % WO3, 3.1 wt. % NiO, and the balance alumina. This catalyst is designated Catalyst iv.

[0127] 5) Catalyst v: Prepared as follows: 1000 g of pseudo-boehmite manufactured by Sinopec Catalyst Co., Ltd., ChangLing Branch was weighed out, and 1000 ml of an aqueous solution containing 10 ml of nitric acid (chemically pure) was added thereto. The mixture was extruded using a twin-screw extruder, dried at 120°C for 4 hours, and then calcined at 800°C for 4 hours to obtain a catalyst support. The resulting product was impregnated in 900 ml of an aqueous solution containing 120 g of ammonium fluoride for 2 hours, dried at 120°C for 3 hours, and calcined at 600°C for 3 hours; after cooling to room temperature, the resulting product was impregnated in 950 ml of an aqueous solution containing 133 g of ammonium metamolybdate for 3 hours, dried at 120°C for 3 hours, and calcined at 600°C for 3 hours; after cooling to room temperature, the resulting product was impregnated in 900 ml of an aqueous solution containing 180 g of nickel nitrate and 320 g of ammonium metatungstate for 4 hours; a fluorided alumina support was impregnated for 4 hours with a mixed aqueous solution containing 0.1 wt% of ammonium metamolybdate (chemically pure) and 0.1 wt% of nickel nitrate (chemically pure) relative to the catalyst support, dried at 120°C for 3 hours, and calcined at 600°C for 4 hours to obtain catalyst v.

[0128] [Table 3]

[0129] Example 1 For the riser reactor pilot plant, experiments were carried out according to the scheme shown in Figure 1 as follows: The 1-pentene feedstock was contacted with a high-temperature catalytic conversion catalyst i having a temperature of 750°C at the bottom of the first reaction zone of the riser reactor under conditions including a reaction temperature of 700°C, a reaction pressure of 0.1 MPa, a reaction time of 5 seconds, and a catalyst to feedstock weight ratio of 45:1.

[0130] Heavy oil I was mixed with the stream from the first reaction zone at the bottom of the second reaction zone of the riser reactor under conditions including a reaction temperature of 530°C, a reaction pressure of 0.1 MPa, a reaction time of 6 seconds, and a weight ratio of catalyst to heavy oil I of 5:1, and contacted with heavy oil I and catalytic conversion catalyst I for reaction.

[0131] The resulting reaction product was separated from the spent catalyst, and the spent catalyst was regenerated by burning coke in a regenerator, and the regenerated catalyst was recycled to the bottom of the riser reactor; the reaction product was separated to obtain ethylene, propylene, butylene, a C5+ olefin-rich stream having an olefin content of 80 wt%, a second catalytic cracking distillate oil having a boiling point above 250°C, etc.

[0132] The second catalytic cracking distillate oil was subjected to a temperature of 350°C, a hydrogen partial pressure of 18 MPa, and a volumetric space velocity of 15 h -1 and a volume ratio of hydrogen to oil of 1500, to obtain a hydrocatalytically cracked distillate oil.

[0133] The separated olefin-rich stream was recycled to the bottom of the first reaction zone for further cracking; the hydrocatalytically cracked distillate was mixed with the heavy feedstock and then recycled to the second reaction zone for further reaction. The reaction conditions and product distribution are listed in Table 3.

[0134] (Comparative Example 1) Experiments were conducted in a pilot plant riser reactor as described in Example 1, with the expectation that no 1-pentene feedstock was introduced into the first reaction zone and no olefin-rich stream was separated, as follows: The catalytic conversion catalyst i having a temperature of 600°C was introduced into the bottom of the riser reactor, and the heavy oil I was contacted and reacted with the catalytic conversion catalyst i at the bottom of the second reaction zone under conditions including a reaction temperature of 530°C, a reaction pressure of 0.1 MPa, a reaction time of 6 seconds, and a weight ratio of catalyst to heavy oil I of 5:1.

[0135] The resulting reaction product was separated from the spent catalyst, and the spent catalyst was regenerated by burning coke in a regenerator, and the regenerated catalyst was recycled to the bottom of the riser reactor; the reaction product was separated to obtain ethylene, propylene, butylene, and a second catalytic cracking distillate oil having a boiling point above 250°C.

[0136] The second catalytic cracking distillate oil was subjected to a temperature of 350°C, a hydrogen partial pressure of 18 MPa, and a volumetric space velocity of 15 h -1 The resulting hydrocatalytically cracked distillate oil was mixed with the heavy feedstock oil and then recycled to the second reaction zone for reaction. The reaction conditions and product distribution are listed in Table 3.

[0137] Example 2 An experiment was carried out in a pilot plant riser reactor as described in Example 1, except that no olefin-rich feedstock from an external source was introduced into the first reaction zone, as follows: The catalytic conversion catalyst i having a temperature of 750°C was introduced into the bottom of the riser reactor, and the heavy oil I was contacted and reacted with the catalytic conversion catalyst i at the bottom of the second reaction zone under conditions including a reaction temperature of 530°C, a reaction pressure of 0.1 MPa, a reaction time of 6 seconds, and a weight ratio of catalyst to heavy oil I of 5:1.

[0138] The resulting reaction product was separated from the spent catalyst, and the spent catalyst was regenerated by burning coke in a regenerator, and the regenerated catalyst was recycled to the bottom of the riser reactor; the reaction product was separated to obtain ethylene, propylene, butylene, a C5+ olefin-containing stream having an olefin content of 80 wt%, a second catalytic cracking distillate oil having a boiling point above 250°C, etc.

[0139] The second catalytic cracking distillate oil was subjected to a temperature of 350°C, a hydrogen partial pressure of 18 MPa, and a volumetric space velocity of 15 h -1 The resulting olefin-rich stream was recycled to the bottom of the first reaction zone for further cracking under conditions including a reaction temperature of 700°C, a reaction pressure of 0.1 MPa, and a reaction time of 5 seconds; the hydrocatalytically cracked distillate was mixed with heavy feedstock oil and then recycled to the second reaction zone for further reaction. The reaction conditions and product distribution are listed in Table 3.

[0140] (Comparative Example 2) Experiments were conducted in a riser reactor pilot plant, where heavy oil I was contacted with catalytic conversion catalyst ii at 680°C at the bottom of the riser reactor under conditions including a reaction temperature of 610°C, a reaction pressure of 0.1 MPa, a reaction time of 6 seconds, and a weight ratio of catalyst to feedstock of 16.9:1.

[0141] The resulting reaction product was separated from the spent catalyst, and the spent catalyst was regenerated by burning the coke in a regenerator. The regenerated catalyst was recycled to the bottom of the riser reactor; the reaction product was not subjected to hydrotreatment or further reaction after separation. The reaction conditions and product distribution are listed in Table 3.

[0142] Example 3 Heavy oil II was used instead of heavy oil I, and the second catalytic cracking distillate oil having a boiling point of more than 250°C was contacted with the hydrodesulfurization catalyst v in the hydrodesulfurization reactor. The reaction pressure was 6.0 MPa, the reaction temperature was 350°C, the volume ratio of hydrogen to oil was 350, and the volumetric space velocity was 2.0 h -1 The experiment was carried out as described in Example 2, except that the reaction was carried out under conditions including:

[0143] (Comparative Example 3) An experiment was conducted in a pilot plant of a riser reactor, and heavy oil II was contacted for reaction with catalytic conversion catalyst iii having a temperature of 680°C at the bottom of the riser reactor under conditions including a reaction temperature of 530°C, a reaction pressure of 0.1 MPa, a reaction time of 6 seconds, and a weight ratio of catalyst to feedstock of 5:1.

[0144] The obtained reaction product was separated from the spent catalyst, and the spent catalyst was regenerated by burning coke in a regenerator, and the regenerated catalyst was recycled to the bottom of the riser reactor; the reaction product obtained after separation was not recycled to the riser reactor for further reaction, and the hydrotreatment of the second catalytic cracked distillate oil was the same as in Example 3. The reaction conditions and product distribution are listed in Table 3.

[0145] Example 4 The experiment was carried out as described in Example 1, except that the reaction conditions shown in Table 3 were used.

[0146] Example 5 The experiment was carried out as described in Example 1, except that the reaction conditions shown in Table 3 were used.

[0147] Example 6 The experiment was carried out as described in Example 1, except that the separated butylene was recycled to the bottom of the riser reactor for cracking under conditions including a reaction temperature of 710°C, a catalyst to butylene weight ratio of 100:1, and a reaction time of 0.2 seconds. The reaction conditions and product distribution are shown in Table 3.

[0148] [Table 4] JPEG0007746389000005.jpg53169

[0149] As can be seen from the results in Table 3, the fluidized catalytic conversion process of the present application achieves higher yields of ethylene, propylene, and butylene compared to Comparative Examples 1-3, with a total yield of the three olefins reaching 50% or more; in Examples 1-3, when olefin cracking was performed at 700°C, the total yield of ethylene, propylene, and butylene in the product reached 60% or more; as the olefin content of the feedstock increased, the yields further improved. For example, when 1-pentene with a 100% olefin content was used as the olefin-rich feedstock (see Example 1), the ethylene yield in the product was 11.43%, the propylene yield was 26.92%, and the butylene yield was 24.01%, resulting in a total yield of 62.36%. As the catalytic cracking temperature increased, the ethylene yield could be further increased, as shown in Example 5; as shown in Example 6, the overall yield of ethylene and propylene could be significantly increased by recycling the butylene in the product.

[0150] Example 7 Experiments were carried out in a pilot plant in a riser reactor according to the scheme shown in Figure 2 as follows: The 1-octene feedstock was contacted for reaction with a high-temperature catalytic conversion catalyst i having a temperature of 750°C at the bottom of the first reaction zone of the riser reactor under conditions including a reaction temperature of 700°C, a reaction pressure of 0.1 MPa, a reaction time of 5 seconds, and a weight ratio of catalyst to feedstock of 45:1.

[0151] Heavy oil I was mixed with the stream from the first reaction zone at the bottom of the second reaction zone of the riser reactor under conditions including a reaction temperature of 530°C, a reaction pressure of 0.1 MPa, a reaction time of 6 seconds, and a weight ratio of catalyst to heavy oil I of 5:1, and contacted with heavy oil I and catalytic conversion catalyst i for reaction.

[0152] The resulting reaction product was separated from the spent catalyst, and the spent catalyst was regenerated by burning coke in a regenerator, and the regenerated catalyst was recycled to the bottom of the riser reactor; the reaction product (reaction product vapor) was separated to obtain ethylene, propylene, butylene, a first catalytic cracking distillate oil, and a second catalytic cracking distillate oil.

[0153] The second catalytic cracking distillate oil was subjected to a temperature of 350°C, a hydrogen partial pressure of 18 MPa, and a volumetric space velocity of 15 h -1 and a volume ratio of hydrogen to oil of 1500 to obtain a hydrocatalytically cracked distillate oil; the hydrocatalytically cracked distillate oil was mixed with the heavy feedstock oil and then recycled to the second reaction zone for further reaction.

[0154] The first catalytically cracked distillate was sent to an olefin separator to separate a first olefin-containing stream (i.e., a stream containing small olefins) having a boiling point below 140°C and a second olefin-containing stream (i.e., a stream containing large olefins) having a boiling point above 140°C and below 250°C; the first olefin-containing stream was recycled to the bottom of the first reaction zone I for further cracking; the second olefin-containing stream was introduced into the bottom of the third reaction zone III downstream of the second reaction zone II for further cracking under conditions including a reaction temperature of 530°C and a reaction time of 5 seconds. The reaction conditions and product distribution are listed in Table 4.

[0155] Example 8 Experiments were carried out in a pilot plant in a riser reactor according to the scheme shown in Figure 3 as follows: The 1-pentene feedstock was contacted for reaction with a high-temperature catalytic conversion catalyst i having a temperature of 750°C at the bottom of the first reaction zone of the riser reactor under conditions including a reaction temperature of 700°C, a reaction pressure of 0.1 MPa, a reaction time of 5 seconds, and a catalyst to feedstock weight ratio of 45:1.

[0156] Heavy oil I was mixed with the stream from the first reaction zone at the bottom of the second reaction zone of the riser reactor under conditions including a reaction temperature of 530°C, a reaction pressure of 0.1 MPa, a reaction time of 6 seconds, and a weight ratio of catalyst to heavy oil I of 5:1, and contacted with heavy oil I and catalytic conversion catalyst i for reaction.

[0157] Methanol was introduced for reaction into the second reaction zone downstream of the introduction position of heavy oil I under conditions including a reaction temperature of 500°C, a reaction pressure of 0.1 MPa, a reaction time of 3 seconds, and a weight ratio of catalyst to methanol of 10:1.

[0158] The resulting reaction product was separated from the spent catalyst, and the spent catalyst was regenerated by burning coke in a regenerator, and the regenerated catalyst was recycled to the bottom of the riser reactor; the reaction product was separated to obtain ethylene, propylene, butylene, a C5+ olefin-rich stream having an olefin content of 80 wt%, a second catalytic cracking distillate oil having a boiling point above 250°C, etc.

[0159] The second catalytic cracking distillate oil was subjected to a temperature of 350°C, a hydrogen partial pressure of 18 MPa, and a volumetric space velocity of 15 h -1 and a volume ratio of hydrogen to oil of 1500, to obtain a hydrocatalytically cracked distillate oil.

[0160] The separated olefin-rich stream was recycled to the bottom of the first reaction zone for further cracking; the hydrocatalytically cracked distillate was mixed with heavy oil I and then recycled to the second reaction zone for further reaction. The reaction conditions and product distribution are listed in Table 4.

[0161] [Table 5]

[0162] As can be seen from the data in Table 4, the processes of Examples 7 and 8 of the present application also provide a total yield of ethylene, propylene and butylene of 60% or more, with the total yield of ethylene and propylene being further improved compared to Example 1, while the total yield of hydrogen, methane and ethane is significantly reduced.

[0163] Although the present application has been described in detail above with reference to preferred embodiments, it is not intended to be limited to these embodiments. Various modifications can be made in accordance with the inventive concept of the present application, and these modifications are within the scope of the present application.

[0164] It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and in order to avoid unnecessary repetition, the present application does not describe various possible combinations, but such combinations are also within the scope of the present application.

[0165] Furthermore, the embodiments of the present application can be arbitrarily combined within the scope of the present application, and the combined embodiments are the disclosure content of the present application. [Brief explanation of the drawings]

[0166] The drawings that form part of this specification are provided to aid in understanding the application and should not be considered limiting. The application may be read with reference to the drawings in combination with the following detailed description. In the drawings: [Figure 1] FIG. 1 shows a schematic flow diagram of a preferred embodiment of the fluidized catalytic conversion process of the present application. [Figure 2] FIG. 2 shows a schematic flow diagram of another preferred embodiment of the fluidized catalytic conversion process of the present application. [Figure 3] FIG. 3 shows a schematic flow diagram of yet another preferred embodiment of the fluidized catalytic conversion process of the present application.

Claims

1. 1. A fluidized catalytic conversion process for producing light olefins from hydrocarbons, comprising the steps of: 1) introducing an olefin-rich feedstock into a first reaction zone of a fluidized catalytic conversion reactor, wherein the olefin-rich feedstock contacts a catalytic conversion catalyst having a temperature of 650°C or greater and reacts under first catalytic conversion conditions, wherein the olefin-rich feedstock has an olefin content of 50 wt% or greater, and the olefins in the olefin-rich feedstock consist of C5+ olefins; 2) introducing a heavy feedstock into a second reaction zone downstream of the fluidized catalytic conversion reactor from the first reaction zone, wherein the heavy feedstock contacts the catalytic conversion catalyst from the first reaction zone after the reaction of step 1) and reacts under second catalytic conversion conditions; 3) separating the effluent of the fluidized catalytic conversion reactor to obtain a reaction product vapor and spent catalyst, and performing a first separation on the reaction product vapor to obtain ethylene, propylene, butylene, a first catalytically cracked distillate oil, and a second catalytically cracked distillate oil; the first catalytically cracked distillate oil has an initial boiling point in the range of more than 20°C and less than 140°C, the second catalytically cracked distillate oil has a final boiling point in the range of more than 250°C and less than 550°C, and a cut point between the first catalytically cracked distillate oil and the second catalytically cracked distillate oil is in the range of 140°C to 250°C; 4) subjecting the first catalytically cracked distillate to a second separation to obtain an olefin-rich stream having a C5+ olefin content of at least 50 wt.%; 5) recycling at least a portion of said olefin-rich stream to step 1) for further reaction; and 7) recycling at least a portion of the butylenes separated in step 3) upstream of the catalytic conversion reactor where the olefin-rich feedstock is introduced to contact a catalytic conversion catalyst for reaction at third catalytic conversion conditions; The first catalytic conversion conditions are: a reaction temperature of 600 to 800°C; a reaction pressure of 0.05 to 1 MPa; a reaction time of 0.01 to 100 seconds; a weight ratio of said catalytic conversion catalyst to said olefin-rich feedstock of (1-200):1; The second catalytic conversion conditions are: a reaction temperature of 400 to 650°C; a reaction pressure of 0.05 to 1 MPa; a reaction time of 0.01 to 100 seconds; a weight ratio of said catalytic conversion catalyst to said heavy feedstock of (1 to 100):1; and The third catalytic conversion condition is: a reaction temperature of 650 to 800°C; a reaction pressure of 0.05 to 1 MPa; Response time of 0.01 to 10 seconds, a weight ratio of said catalytic conversion catalyst to said butylenes of (20-200):

1.

2. 10. The method of claim 1 further comprising the steps of: 6) contacting the second catalytically cracked distillate with a hydrogenation catalyst to react under hydrogenation conditions to obtain a hydrotreated catalytically cracked distillate, and recycling the hydrotreated catalytically cracked distillate to the second reaction zone of the fluidized catalytic conversion reactor for further reaction.

3. The hydrogenation conditions are: hydrogen partial pressure of 3.0-20.0 MPa, reaction temperature of 300-450°C, volume ratio of hydrogen to oil of 300-2000, and 0.1-3.0 h －１ The method of claim 2, comprising a volumetric space velocity of

4. The first catalytic conversion conditions are: a reaction temperature of 630 to 780°C; a reaction pressure of 0.1 to 0.8 MPa; a reaction time of 0.1 to 80 seconds; a weight ratio of the catalytic conversion catalyst to the olefin-rich feedstock of (3 to 180):1; The second catalytic conversion conditions are: a reaction temperature of 450 to 600°C; a reaction pressure of 0.1 to 0.8 MPa; a reaction time of 0.1 to 80 seconds; a weight ratio of said catalytic conversion catalyst to said heavy feedstock of (3 to 70):1; and The third catalytic conversion condition is: a reaction temperature of 680 to 780°C; a reaction pressure of 0.1 to 0.8 MPa; 0.05-8 second reaction time, 4. The process of claim 1, comprising a weight ratio of said catalytic conversion catalyst to said butylenes of (30-180):

1.

5. The method of any one of claims 1 to 4, further comprising: 2a) introducing an oxygen-containing organic compound into a second reaction zone of the fluidized catalytic conversion reactor to contact the catalytic conversion catalyst in the second reaction zone of the fluidized catalytic conversion reactor for reaction under fourth catalytic conversion conditions; The fourth contact conversion condition is: a reaction temperature of 300 to 550°C; a reaction pressure of 0.05 to 1 MPa; a reaction time of 0.01 to 100 seconds; a weight ratio of said catalytic conversion catalyst to said oxygen-containing organic compound of (1-100):1;

6. The fourth catalytic conversion condition is: a reaction temperature of 400 to 530°C; a reaction pressure of 0.1 to 0.8 MPa; Response time of 0.1 to 80 seconds, a weight ratio of catalytic conversion catalyst to the oxygen-containing organic compound of (3 to 80):1; 6. The method of claim 5, wherein the oxygen-containing organic compound comprises at least one of methanol, ethanol, dimethyl ether, methyl ethyl ether, and ethyl ether.

7. 7. The method of any one of claims 1 to 6, further comprising the steps of: 8) regenerating the spent catalyst obtained by the separation in step 3) by coke combustion to obtain a regenerated catalyst having a temperature of 650°C or higher, and then recycling the regenerated catalyst to the first reaction zone upstream of the fluidized catalytic conversion reactor for use as the catalytic conversion catalyst.

8. the olefin-rich feedstock has an olefin content of 80 wt% or greater; the olefin-rich feedstock is at least one of a C5+ fraction produced by an alkane dehydrogenation unit, a C5+ fraction produced by a catalytic cracking unit of a refinery, a C5+ fraction produced by a steam cracking unit of an ethylene plant, a C5+ olefin-rich by-product fraction of an MTO process, and a C5+ olefin-rich by-product fraction of an MTP process; The method according to any one of claims 1 to 7.

9. 9. The process of claim 8, wherein the olefin-rich feedstock is a pure olefin feedstock.

10. 9. The method of claim 8, wherein the heavy feedstock is selected from petroleum hydrocarbons and / or mineral oils; the petroleum hydrocarbons are selected from vacuum gas oil, atmospheric gas oil, coker gas oil, deasphalted oil, vacuum resid, atmospheric resid, heavy aromatic raffinate, or combinations thereof; and the mineral oil is selected from coal liquids, oil sands oil, shale oil, or combinations thereof.

11. The catalytic conversion catalyst comprises, based on the weight of the catalytic conversion catalyst, 1 to 50 wt % of a molecular sieve, 5 to 99 wt % of an inorganic oxide, and 0 to 70 wt % of a clay; the molecular sieve comprises one or more of a macroporous molecular sieve, a mesoporous molecular sieve, and a microporous molecular sieve; The catalytic conversion catalyst further comprises 0.1 to 3 wt % of a reforming element based on the weight of the catalytic conversion catalyst, and the reforming element is one or more selected from the group consisting of Group VIII metals, Group IVA metals, Group V metals, and rare earth metals. The method according to any one of claims 1 to 10.

12. The hydrogenation catalyst comprises, based on the weight of the hydrogenation catalyst, 20 to 90 wt. % of a support, 10 to 80 wt. % of a supported metal, and 0 to 10 wt. % of an additive; the support is alumina and / or amorphous silica-alumina, the additive is selected from fluorine, phosphorus, titanium, platinum, or a combination thereof, and the supported metal is a Group VIB metal and / or a Group VIII metal. The method according to claim 2 or 3.

13. 13. The process according to any one of claims 1 to 12, wherein the olefin-rich stream obtained in step 4) has a C5+ olefins content of at least 80%.

14. The process of any one of claims 1 to 11, wherein the fluidized catalytic conversion reactor is selected from a fluidized bed reactor and a riser reactor.

15. 6. The method of claim 5, wherein the oxygen-containing organic compound is fed to the second reaction zone of the fluidized catalytic conversion reactor after mixing with the heavy feedstock, or is fed to the second reaction zone of the fluidized catalytic conversion reactor downstream of the location where the heavy feedstock is introduced.

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