Process for the production of petrochemical bases comprising fluid catalytic cracking, oligocracking, fixed bed hydrocracking, catalytic reforming and steam cracking

Abstract

The present invention relates to a process for producing olefins and aromatics from a hydrocarbon feedstock comprising crude oil, the process comprising the following steps: a) an atmospheric distillation step; b) a fluid catalytic cracking step; c) a fixed bed hydrocracking step; d) a steam cracking step; e) a catalytic reforming step; f) an aromatics transformation and / or separation step; g) a one-step oligomerization and catalytic cracking step. Figure 1 to be published

Description

Title of the invention: Process for producing bases for petrochemicals comprising fluid catalytic cracking, oligo-cracking, fixed bed hydrocracking, catalytic reforming and steam cracking Technical field

[0001] The present invention relates to a process for producing olefins and aromatics for the petrochemical industry from a crude oil feedstock. Prior art

[0002] The improvement of engines and the progressive electrification of some vehicles have led to a change in the demand for petroleum products with a tendency to reduce the growth in demand for fuels. Conversely, the growth in demand for petrochemical bases and in particular for olefins is more sustained. Ethylene and propylene are, for example, highly sought-after olefins, because they are essential intermediates for many petrochemical products such as polyethylene or polypropylene. There is therefore an interest in remodeling refining sites, so as to produce at least part of petrochemical bases, or to design new integrated refining-petrochemical schemes, or to design sites where the majority or all of the crude is converted into petrochemical bases.

[0003] The main process for converting hydrocarbon fractions into olefins with high yield is steam cracking. The production of the desired olefins is accompanied by co-products, in particular aromatic compounds and pyrolysis oil which require purification steps. In addition, the selectivity for the desired olefins is highly dependent on the quality of the feedstocks introduced into the steam cracking step. There is therefore an interest in identifying new processes for producing olefins from heavy hydrocarbon fractions in a more efficient, cost-effective manner and independent of the heavy hydrocarbon fraction treated, including poor quality feedstocks for steam cracking.

[0004] Furthermore, the main process for producing aromatic compounds is catalytic reforming, which is generally associated with complex separation and transformation steps in a section called "aromatic complex". This aromatic complex produces commercial grade aromatic molecules (generally among benzene, toluene, ortho and para xylene), as well as a certain number of by-products, including raffinate which can be advantageously used as a feedstock for steam cracking. Conversely, steam cracking produces a cut rich in aromatics that can be usefully recovered in the aromatic complex. It is therefore beneficial to exploit the synergy of steam cracking with the aromatic complex to improve the economic profitability of a petrochemical complex.

[0005] Among the processes for converting heavy fractions of atmospheric residue hydrocarbons, fluid catalytic cracking of residues is today a key process in modern refineries to produce olefins and distillates in particular. Due to the impurity content of certain atmospheric residue feedstocks, residue hydrotreatment units are often installed upstream to reduce the impurity content, in particular sulfur, metals and Conradson carbon (CCR). The effluent from the hydrotreatment stage is generally subjected to a separation stage to remove atmospheric gases and distillates. The atmospheric residue, hydrotreated if necessary, obtained in the separation stage is sent to fluid catalytic cracking.

[0006] Fluid catalytic cracking is known by the acronym FCC (abbreviation of the English terminology "Fluid Catalytic Cracking") which can group together several technologies such as for example RFCC (abbreviation of the English terminology "Resid Fluid Catalytic Cracking") marketed under the acronym R2R™ by the company Axens, or high severity fluid catalytic cracking marketed under the acronym HSFCC™ (abbreviation of the English terminology "High Severity Fluid Catalytic Cracking") by the company Axens.

[0007] Document WO2020205210 discloses a process flowsheet for converting a hydrocarbon feedstock into olefins and / or aromatics by sending this feedstock directly to a steam cracking unit without going through a conventional crude distillation unit. The unit is composed of three stages where for each of them, the feedstock is heated in a convection zone before being separated in a flash drum into a vapor phase sent to the radiation zone of the steam cracking to be cracked or to a conversion, hydrotreatment, hydrocracking or FCC unit, and into a liquid phase sent to the next heating and separation stage or to the residue hydrotreatment / hydrocracking unit for the liquid phase recovered at the last separation stage. The process multiplies the fractionation steps in the steam cracking unit.This document does not disclose any pretreatment (hydrotreatment / hydrocracking) of the feedstocks sent to the steam cracking unit. The liquid fraction at the outlet of the 3rd and final separation stage corresponding to the heaviest part of the feedstock is sent to a residue hydroconversion unit and not directly to the FCC unit.

[0008] Document WO202096979 discloses a process diagram for converting a hydrocarbon feedstock comprising an initial separation of the feedstock into two phases: a steam-cracked vapor phase and a liquid phase sent to an FCC. This separation is not carried out in a conventional distillation column but in a separator drum placed downstream of the feedstock heating step which can be carried out in the convection zone of a steam cracker furnace in the presence of an aqueous fluid. This document does not disclose a specific treatment of the diesel cut by hydrocracking to maximize the production of olefins and aromatics. Nor does it include the separation of FCC gasoline into light and heavy cuts in order to adapt their treatment according to the downstream units (steam cracking, reforming or aromatics extraction).

[0009] Document WO201659568 discloses a process for the production of numerous petrochemical products, including cumene or polycarbonate from a crude hydrocarbon feedstock. The process comprises atmospheric distillation, steam cracking or FCC units. The feedstock of the FCC unit is a light feedstock such as naphtha, vacuum gas oil, and not a heavy feedstock such as atmospheric residue. Kerosene and diesel cuts are not converted into naphtha in a hydrocracker in order to maximize the production of aromatics and olefins.

[0010] Document WO201894353 discloses a process for converting a crude oil feedstock into light olefins, aromatics, and fuels (such as kerosene, diesel, etc.). This process comprises steps of atmospheric distillation, steam cracking, hydrocracking, FCC, reforming, and aromatics extraction. The process also comprises a vacuum distillation step from which a vacuum gas oil cut is withdrawn to be hydrocracked or hydrotreated and then sent to the FCC. This document does not disclose a treatment of the atmospheric residue in the FCC. In addition, this document does not disclose hydrocracking of atmospheric diesel to maximize the production of naphtha to be sent to the steam cracker.

[0011] The present invention aims to distinguish itself from the petrochemical base production processes of the prior art by providing a process allowing conversion of the major part of a hydrocarbon feedstock comprising crude oil into petrochemical bases. This process includes a step of conversion of the atmospheric residue using fluid catalytic cracking, a step of oligomerization and catalytic cracking in a single step (also called oligocracking) of the olefins of the FCC and LPG gasoline cuts resulting from the fluid catalytic cracking step as well as in one embodiment separate hydrocracking steps treating different distillate cuts depending on their origin for the production of light and / or heavy naphtha intended for steam cracking and catalytic reforming steps to produce olefins and aromatics. Summary of the invention

[0012] The present invention relates to a process for producing olefins and aromatics from a hydrocarbon feedstock comprising crude oil, the process comprising the following steps:

[0013] a) an atmospheric distillation step comprising the treatment of all or part of the hydrocarbon feedstock comprising crude oil in an atmospheric distillation unit, and obtaining a naphtha cut, a diesel cut and an atmospheric residue cut;

[0014] b) a fluid catalytic cracking (FCC) step comprising the treatment of all or part of the atmospheric residue cut obtained in step a) in an FCC unit comprising a catalytic cracking zone operating in ascending or descending flow containing an FCC catalyst, operating at a temperature at the outlet of the catalytic cracking zone of between 400 and 700°C, at a pressure of the catalytic cracking zone of between 0.1 and 2 MPa, and obtaining an LPG cut, an FCC gasoline cut and a light distillate cut (LCO);

[0015] c) a fixed-bed hydrocracking step comprising the treatment of all or part of a diesel and / or light distillate (LCO) cut chosen from the cuts obtained in steps a) and b) alone or as a mixture in a hydrocracking unit comprising a reactor containing a hydrocracking catalyst, operated in the presence of hydrogen, at a temperature between 250 and 480°C, under a pressure between 2 and 25 MPa, and obtaining a light naphtha cut and a heavy naphtha cut;

[0016] d) a steam cracking step comprising the treatment of all or part of the naphtha and / or light naphtha and / or heavy naphtha and / or cuts essentially comprising propylene and ethylene chosen from the cuts obtained in steps a), c) and g) alone or as a mixture in a steam cracking unit comprising a pyrolysis furnace, and obtaining an olefinic cut;

[0017] e) a catalytic reforming step comprising the treatment of all or part of the heavy naphtha cut obtained in step c) in a catalytic reforming unit comprising a reactor containing a reforming catalyst, operated under a pressure of between 0.1 and 25 MPa and at a temperature of between 480 and 570°C, and obtaining a reformate cut;

[0018] f) a step of transformation and / or separation of the aromatics comprising the treatment of all or part of the reformate cut obtained in step e) in a unit of transformation and / or separation of the aromatics, and the obtaining of an aromatic cut;

[0019] g) a one-step oligomerization and catalytic cracking step, comprising the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained from step b) of fluid catalytic cracking in a single-stage oligomerization and catalytic cracking unit comprising a reactor containing a catalyst allowing the oligomerization and catalytic cracking of olefins, operated at a temperature of between 400 and 600°C, and at a pressure of between 0.1 and 1 MPa, and obtaining a cut essentially comprising propylene and ethylene.

[0020] The method according to the present invention has the following advantages: • the conversion into petrochemical bases (olefins and aromatics) of the majority of the hydrocarbon feedstock comprising crude oil, with a yield greater than 70% by weight, preferably 75% by weight of petrochemical bases relative to the weight of the feedstock. • Process flexibility allowing the treatment of all heavy hydrocarbon fractions regardless of their origin. • The flexibility to direct production towards more olefins or, on the contrary, more aromatic compounds, and / or to direct selectivity towards a particular olefin or aromatic, depending on market demand, by adjusting the types of processes to be implemented, the operating parameters and the routing of flows. • The conversion into cuts capable of feeding the steam cracking and / or catalytic reforming stages of almost all the effluents obtainable by the distillation, fluid catalytic cracking and hydrocracking units, as well as the recycling of almost all the unwanted cuts obtained in the steam cracking and / or catalytic reforming stages to the fluid catalytic cracking and / or hydrocracking units, thus making it possible to obtain an overall process optimized for the production of petrochemical bases with a high yield from a hydrocarbon feedstock comprising crude oil. DETAILED DESCRIPTION OF THE INVENTION

[0021] According to the present invention, the expression "between ... and ..." and "between .... and ..." are equivalent and mean that the limit values ​​of the interval are included in the range of values ​​described. If this is not the case and the limit values ​​are not included in the range described, such precision will be provided by the present invention.

[0022] In the sense of the present invention, the different parameter ranges for a given step such as pressure ranges and temperature ranges can be used alone or in combination. For example, in the sense of the present invention, a preferred pressure value range can be combined with a more preferred temperature value range. The pressures are given in absolute terms in the present application.

[0023] In the following, particular embodiments of the invention may be described. They may be implemented separately or combined with each other, without limitation of combinations when this is technically feasible.

[0024] Throughout this text, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, group VIIIB according to the CAS classification corresponds to the metals of columns 8, 9 and 10 according to the new IUP AC classification, and group IB according to the CAS classification corresponds to the metals of column 11 according to the new IUP AC classification.

[0025] The term “gas cut” means: a cut essentially comprising light gases or alkanes from C1 to C4, i.e. methane, ethane, propane, iso-butane and normal-butane.

[0026] The term LPG cut means: a cut essentially comprising light gases or C3 and C4 alkanes, i.e. propane, iso-butane and normal-butane.

[0027] Naphtha cut means: a cut essentially comprising hydrocarbon compounds boiling in a range between 28 and 180°C.

[0028] Light naphtha cut means: a cut essentially comprising hydrocarbon compounds boiling in a range between 28 and 101°C.

[0029] Heavy naphtha cut means: a cut essentially comprising hydrocarbon compounds boiling in a range between 65 and 180°C.

[0030] The cutting point between light naphtha and heavy naphtha can vary between 65 and 101°C.

[0031] Diesel cut means: a cut essentially comprising hydrocarbon compounds boiling in a range between 175 and 350°C.

[0032] Kerosene cut means: a cut essentially comprising hydrocarbon compounds boiling in a range between 175 and 220°C.

[0033] Atmospheric residue cut means: a cut essentially comprising hydrocarbon compounds boiling above 350°C, and produced by distillation of the crude oil feedstock.

[0034] “Essentially comprising” means: the main constituent(s) of which in mass is / are.

[0035] The term purge cut means: a cut resulting from diesel hydrocracking processes essentially comprising hydrocarbon compounds boiling above 175°C.

[0036] The term “olefinic cut” means: a cut comprising more than 99% by weight, preferably more than 99.5% by weight of olefins, preferably having from 2 to 4 carbon atoms.

[0037] The term C4 cut means: a cut essentially comprising hydrocarbon compounds having 4 carbon atoms.

[0038] The term reformate cut means: a cut from the catalytic reformer comprising more than 75% by weight of aromatic hydrocarbon compounds.

[0039] Aromatic cut means: a cut comprising more than 99% by weight, preferably more than 99.5% of aromatic hydrocarbon compounds.

[0040] The term raffinate cut means: a cut derived from the aromatic complex comprising essentially non-aromatic hydrocarbon compounds having from 5 to 8 carbon atoms.

[0041] Light pyrolysis gasoline cut means: the fraction of the steam cracking effluent containing hydrocarbons with 6 to 8 carbon atoms.

[0042] Heavy pyrolysis gasoline cut means: the fraction of the steam cracking effluent containing hydrocarbons with 9 to 10 carbon atoms.

[0043] Pyrolysis oil cut means: the fraction of the steam cracking effluent containing hydrocarbons with 11 carbon atoms or more.

[0044] Heavy aromatic fraction means: a fraction derived from the aromatic complex comprising mainly aromatic compounds having 9 and 10 carbon atoms. Charge

[0045] The process according to the invention is a process for producing olefins and aromatics from a hydrocarbon feedstock comprising crude oil.

[0046] Advantageously, the hydrocarbon feedstock consists essentially of crude oil, preferably the hydrocarbon feedstock consists of crude oil.

[0047] Crude oil means any type of oil from any geological source and in unrefined form.

[0048] The crude oil may advantageously be chosen from Arabian Heavy, Arabian Medium, Arabian Light, Arabian Extra Light, other Gulf crudes, Brent, North Sea crude, North and West African crude, Urals crude, Indonesian crude, Chinese crude, or a mixture of them.

[0049] This advantageously corresponds to a crude having the following characteristics: - Density at 15°C less than 1.1 - Sulphur content less than 7% by weight - Metal content (Nickel + Vanadium) less than 1000 ppm - Asphaltene content (insoluble nC7) less than 15% by weight Step a) atmospheric distillation

[0050] The process according to the invention comprises a step a) of atmospheric distillation comprising the treatment of all or part of the hydrocarbon feedstock comprising crude oil in an atmospheric distillation unit, and the obtaining of a naphtha cut, a diesel cut and an atmospheric residue cut.

[0051] Advantageously, a portion of the diesel cut is used for the production of a low sulfur fuel oil (or BTS fuel oil).

[0052] In one embodiment, in step a) of atmospheric distillation, a gas cut is further obtained. Advantageously, an LPG cut can be separated from the gas cut.

[0053] In one embodiment, in step a) of atmospheric distillation of the crude oil feedstock, a kerosene cut is also obtained. Advantageously, a portion of this kerosene cut is used for the production of a low-sulfur fuel oil (or BTS fuel oil).

[0054] Atmospheric distillation of the crude oil feedstock makes it possible to separate the different components according to their evaporation temperature. The crude oil is advantageously desalted then preheated and injected into a distillation tower and heated to approximately 400°C. The cuts comprising the lightest hydrocarbons are recovered in gaseous form at the top of the column, such as the gas and naphtha cuts. The cuts with an intermediate boiling range, such as the diesel cut, are withdrawn laterally in the middle section of the tower. The cuts with a higher boiling point, such as the atmospheric residue cut, remain in the lower part of the tower and are sent to an FCC unit or, optionally, to a residue hydrotreatment stage. Step b) of fluid catalytic cracking

[0055] The process according to the invention comprises a step b) of fluid catalytic cracking comprising the treatment of all or part of the atmospheric residue cut obtained in step a) in an FCC unit comprising a catalytic cracking zone operating in ascending or descending flow containing an FCC catalyst, operating at a temperature at the outlet of the catalytic cracking zone of between 400 and 700°C, preferably between 450 and 650°C, at a pressure of the catalytic cracking zone of between 0.1 and 2 MPa, preferably between 0.15 and 0.5 MPa, and obtaining an LPG cut, an FCC gasoline cut and a light distillate cut (LCO).

[0056] Advantageously, the catalytic cracking zone operates with a catalyst to feedstock ratio entering said zone of between 1 and 100 wt / wt, preferably between 5 and 80 wt / wt.

[0057] Advantageously, the residence time of the catalyst in the catalytic cracking zone is between 0.5 and 20 s, preferably between 1 and 10 s.

[0058] In one embodiment, a co-feed may be treated in fluid catalytic cracking step b) jointly or separately with the atmospheric residue cut obtained in step a) or in one embodiment with the hydrotreated atmospheric residue cut obtained in the optional residue hydrotreatment step k). This co-feed may be an effluent recycled from another step of the process. according to the invention in order to maximize the yield of petrochemical bases and / or to promote the production of one or more recoverable products.

[0059] In one embodiment, the co-feed is all or part of the hydrotreated LCO cut obtained in the optional step 1) of LCO hydrotreatment. This option makes it possible to crack the LCO cut obtained in step b) previously hydrotreated without requiring an additional hydrocracking step and to modulate the yields of petrochemical bases.

[0060] In an FCC unit, the heat balance is ensured by the combustion of the coke deposited on the FCC catalyst during the catalytic reaction. This combustion takes place in a regeneration zone by injection of air via a compressor called the main air compressor (abbreviated MAB, an abbreviation of the English terminology for "main air blower").

[0061] Advantageously, the FCC catalyst enters the regeneration zone of the reactor with a coke content (defined as the mass of coke over the mass of catalyst) of between 0.5% and 1%, and leaves said zone with a coke content of less than 0.01%. During this step, combustion fumes are generated and exit the regeneration zone at temperatures of between 550 and 850°C, preferably between 600 and 800°C. These fumes will then, depending on the configurations of the unit, undergo a certain number of post-treatments.

[0062] The Conradson carbon content of the feedstock entering the reactor (abbreviated as CCR and defined for example by ASTM D 482) provides an assessment of coke production during catalytic cracking. Depending on the Conradson carbon content of the feedstock, the coke yield requires specific unit sizing to satisfy the heat balance.

[0063] Thus, when the feedstock has a CCR leading to a coke content higher than that required to ensure the heat balance, the excess heat must be removed. This can be done, for example, and in a non-exhaustive manner, by installing a heat exchanger well known to those skilled in the art, which performs external cooling of a fraction of the catalyst contained in the regenerator by exchange with water, thus leading to the production of high-pressure steam.

[0064] The FCC catalyst advantageously consists of particles with an average diameter of between 40 and 140 pm, preferably between 50 and 120 pm.

[0065] Advantageously, the FCC catalyst comprises a suitable matrix such as alumina, silica or silica-alumina with the presence or absence of a Y-type zeolite dispersed in this matrix.

[0066] The FCC catalyst may further comprise a zeolite having shape selectivity of one of the following structural types: MEL (e.g. ZSM-11), MFI (e.g. ZSM-5), NES, EUO, FER, CHA (e.g. SAPO-34), MFS, MWW. It may also include one of the following zeolites: NU-85, NU-86, NU-88 and IM-5, which also exhibit shape selectivity. The advantage of these shape-selective zeolites is the achievement of better propylene / isobutene selectivity, i.e. a higher propylene / isobutene ratio in the cracking effluents.

[0067] Advantageously, the proportion of zeolite exhibiting shape selectivity relative to the total amount of zeolite in the FCC catalyst may vary depending on the feedstocks used in the FCC step and the structure of the desired products. Advantageously, from 0.1% to 60%, preferably from 0.1% to 40%, and in particular from 0.1% to 30% by weight of zeolite exhibiting shape selectivity is used.

[0068] Advantageously, the zeolite(s) may be dispersed in a matrix based on silica, alumina or silica-alumina, the proportion of zeolite (all zeolites combined) relative to the weight of the FCC catalyst being between 0.7% and 80% by weight, preferably between 1% and 50% by weight, and more preferably between 5% and 40% by weight.

[0069] In the case where several zeolites are used, they can be incorporated into a single matrix or into several different matrices.

[0070] In one embodiment, the FCC catalyst used in the catalytic cracking zone may consist of an ultra-stable Y-type zeolite dispersed in an alumina, silica, or silica-alumina matrix, to which a ZSM5 zeolite-based additive has been added, the ZSM5 crystal content in the FCC catalyst being less than 30% by weight.

[0071] Said fluid catalytic cracking step can be carried out with a catalytic cracking zone operating in ascending flow (called "riser" in English terminology), as well as in units using a catalytic cracking zone operating in descending flow (called "downer" in English terminology). Preferably, the catalytic cracking zone operates in descending flow like the HSFCC high severity fluid catalytic cracking technology marketed under the acronym HSFCC™ (abbreviation of the English terminology "High Severity Fluid Catalytic Cracking") by the company Axens.

[0072] Generally speaking, the fluid catalytic cracking process makes it possible to convert heavy hydrocarbon feedstocks into lighter hydrocarbon fractions ranging from dry gases to a conversion residue. The following cuts can advantageously be distinguished among the effluents, which are conventionally defined according to their composition or their boiling temperature (standard cut points given for information purposes):

[0073] - dry and acid gases (essentially: H2, H2S, methane, ethane),

[0074] - an LPG cut containing C3 and C4 hydrocarbon compounds,

[0075] - a gasoline cut of FCC containing at least 80% of hydrocarbon compounds having a boiling point between 30 and 220°C (standard cutting point), sometimes separated into light FCC gasoline known as LCN ("Light Cracked Naphtha" according to Anglo-Saxon terminology) and heavy FCC gasoline known as HCN ("Heavy Cracked Naphtha" according to Anglo-Saxon terminology), the cutting point between LCN and HCN being able to vary between 65 and 101°C,

[0076] - a light distillate cut known as LCO ("Light Cycle Oil" according to the ter Anglo-Saxon minology) containing at least 80% of hydrocarbon compounds having a boiling point between 220°C and 360°C,

[0077] - a heavy distillate cut sometimes known as HCO ("heavy Cycle Oil" according to Anglo-Saxon terminology) containing at least 80% of hydrocarbon compounds having a boiling point between 360°C and 440°C,

[0078] - possibly a residue of FCC ("slurry" according to Anglo-Saxon terminology) which is generally purified of the catalyst particles it contains to obtain a clarified oil (CO) or a decanted oil (DO). This residue contains at least 80% of hydrocarbon compounds with a boiling point above 440°C.

[0079] In one embodiment, when the optional residue hydrotreatment step k) is implemented, the atmospheric residue cut treated in fluid catalytic cracking step b) is the hydrotreated atmospheric residue cut obtained in step k).

[0080] In one embodiment, in step b) of fluid catalytic cracking, a cut is further obtained comprising essentially C1 and C2 hydrocarbon compounds.

[0081] In one embodiment, in step b) of fluid catalytic cracking, a heavy oil cut is also obtained. Advantageously, this heavy oil cut is used for the production of a low sulfur fuel oil (or BTS fuel oil).

[0082] The term heavy oil is used here to define any heavy cut resulting from step b) of fluid catalytic cracking, and containing at least 80% of hydrocarbon compounds having a boiling point above 360°C. It is understood that this cut may undergo a step of separation of the catalyst particles. Stage c) fixed bed hydrocracking

[0083] The process according to the invention comprises a fixed bed hydrocracking step c) comprising the treatment of all or part of a diesel and / or light distillate (LCO) cut chosen from the cuts obtained in steps a) and b) alone or as a mixture in a hydrocracking unit comprising a reactor containing a hydrocracking catalyst, operated in the presence of hydrogen, at a temperature between 250 and 480°C, preferably between 300 and 420°C, under a pressure of between 2 and 25 MPa, and obtaining a light naphtha cut and a heavy naphtha cut.

[0084] Advantageously, step c) is carried out at an hourly volumetric velocity, defined as being the ratio between the total volumetric flow rate of the treated feedstock and the total volume of catalyst and noted WH (or LHSV liquid hourly space velocity according to English terminology), of between 0.3 and 6 h1, preferably between 1 and 3 h1.

[0085] Advantageously, step c) is carried out at a hydrogen / hydrocarbon volume coverage (denoted H2 / HC) of between 100 and 2000 NmVm3 (normal cubic meters (Nm3) per cubic meter (m3)).

[0086] Preferably, the hydrocracking catalyst is chosen from conventional hydrocracking catalysts known to those skilled in the art.

[0087] Advantageously, the hydrocracking catalyst is of the bifunctional type combining an acid function with a hydrogenating function. The acid function is provided by supports with large surfaces (generally 150 to 1200 m2.g-') having a surface acidity, such as halogenated aluminas (chlorinated or fluorinated in particular), combinations of boron and aluminum oxides, amorphous silica-aluminas and / or zeolites. The hydrogenating function is provided either by one or more metals from group VIIIB, or by a combination of one or more metals from group VIB and one or more metals from group VIIIB.

[0088] Preferably, the hydrocracking catalyst comprises a hydrogenating function composed of one or more metals from group VIB and one or more metals from group VIIIB, taken alone or as a mixture, said catalyst being a sulfide phase catalyst.

[0089] The metal(s) from group VIB are advantageously chosen from chromium, molybdenum and tungsten, alone or as a mixture and preferably chosen from molybdenum and tungsten. Preferably, the content of metal from group VIB in the hydrocracking catalyst is advantageously between 5 and 35% by weight and preferably between 10 and 30% by weight, very preferably between 15 and 22% by weight, the percentages being expressed as percentage by weight of oxides.

[0090] The metal(s) from group VIIIB are advantageously chosen from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum, and preferably from cobalt or nickel. Preferably, the content of metal from group VIIIB in the hydrocracking catalyst is advantageously between 0.5 and 15.0% by weight and preferably between 2.0 and 10.0% by weight, very preferably between 2.5 and 6.0% by weight, the percentages being expressed as percentage by weight of oxides.

[0091] The hydrocracking catalyst may optionally comprise at least one promoter element deposited on the catalyst chosen from the group formed by phosphorus, boron and silicon, optionally one or more elements from group VIIA (chlorine, fluorine preferred), optionally one or more elements from group VIIB (manganese preferred), and optionally one or more elements from group VB (niobium preferred).

[0092] Preferably, the hydrocracking catalyst comprises an acid function chosen from alumina, silica alumina and zeolites, preferably chosen from Y zeolites and preferably chosen from silica alumina and zeolites.

[0093] In one embodiment, fixed bed hydrocracking step c) further comprises the treatment of all or part of the heavy pyrolysis gasoline cut obtained in steam cracking step d).

[0094] In one embodiment, in step c) of fixed bed hydrocracking, when the optional step k) of residue hydrotreatment is implemented, the diesel cut can also be chosen in step k).

[0095] In one embodiment, in hydrocracking step c), the diesel and / or LCO and heavy pyrolysis gasoline cuts are treated jointly in the same hydrocracking section, or separately in separate hydrocracking sections.

[0096] Advantageously, the hydrocracking step c) comprises the treatment of all or part of the heavy pyrolysis gasoline cut from the steam cracking step d) and / or a first part of the diesel cut from the atmospheric distillation step a) in a first hydrocracking section c-S1), and the treatment of all or part of the light distillate cut (LCO) obtained in the fluid catalytic cracking step b) and / or all or part of the diesel cut obtained in the optional residue hydrotreatment step k) and / or a second part of the diesel cut from the atmospheric distillation step a) in a second hydrocracking section c-S2). This embodiment makes it possible to have two sections of equivalent capacity, and makes it possible to dilute the olefins contained in the LCO cut in order to better control the exotherms.This configuration also makes it possible to optimize the operating conditions applied to each of the charges, and consequently, to maximize the yield of recoverable products from the complex, and / or to minimize the catalytic cost of the whole.

[0097] Advantageously, a hydrocracking unit consists of a hydrotreatment reactor followed by two hydrocracking reactors.

[0098] In one embodiment, in step c) of fixed-bed hydrocracking, a gas cut is also obtained. Advantageously, an LPG cut can be separated from the gas cut.

[0099] In one embodiment, in step c) of fixed-bed hydrocracking, a purge cut is also obtained. Advantageously, this purge cut is used for the production of a low-sulfur fuel oil (or BTS fuel oil). Step d) of steam cracking

[0100] The process according to the invention comprises a step d) of steam cracking comprising the treatment of all or part of the naphtha and / or light naphtha and / or heavy naphtha and / or cuts essentially comprising propylene and ethylene chosen from the cuts obtained in steps a), c) and g) alone or as a mixture in a steam cracking unit comprising a pyrolysis furnace, and obtaining an olefinic cut.

[0101] The steam cracking step d) advantageously consists of the non-catalytic decomposition under the combined effect of a high temperature and a low pressure in the presence of water vapor, of saturated hydrocarbons, in order to produce aliphatic or aromatic unsaturated hydrocarbon cuts. Said cuts are then used for the synthesis of a large number of products, for example polyethylene or polypropylene. In the case of the process according to the invention, the steam cracking step d) advantageously makes it possible to produce mainly aliphatic unsaturated hydrocarbons.

[0102] The operating conditions are adjusted according to the nature of the feed entering the steam cracking unit and the yields targeted for each of the main products.

[0103] Advantageously, the residence time in the pyrolysis furnace is limited in order to limit the formation of heavy products. In addition, quenching of the effluent is implemented in order to freeze the composition of the effluent at the outlet of the furnace.

[0104] Advantageously, the temperature at which the pyrolysis furnace is operated depends on the nature of the load.

[0105] Advantageously, the steam cracking step is carried out in a unit which consists of a certain number of pyrolysis furnaces, quenching boilers and a fractionation train. All or part of the steam cracking feed enters the hot section of the unit via the convection zone of the furnace where it is preheated, then it is mixed with the water vapor also preheated in this same zone; the hydrocarbons and the water then pass through the actual radiation zone of the furnace where the rapid rise in temperature and the pyrolysis reactions take place. At the outlet of the furnace, the effluents are, in order to avoid any subsequent reaction, frozen in their kinetic possibilities of evolution by a sudden quench generally carried out in two stages: a first indirect quench with water, followed by a direct quench using the heavy residue by-product of the pyrolysis.The effluents and possibly part of the steam cracking feed are then transferred to a primary fractionation tower which separates at the bottom a heavy cut called "pyrolysis oil" and, by withdrawal, a part of the "pyrolysis gasoline" cut and water, while the light pyrolysis products exit at the top in gaseous form. After compression, washing with soda (intended to eliminate H2S and acid gases) and drying, these light effluents then enter the cold section of the unit which can be designed in various ways, but which ensures separation into various cuts of interest.

[0106] Advantageously, when the feedstock treated in the steam cracking unit is a naphtha cut and / or light naphtha and / or heavy naphtha and / or raffinate, the residence time of the incoming feedstock is between 0.1 and 0.4 seconds, the temperature at the tube outlet is between 700 and 900°C, preferably between 780 and 880°C, and the steam / feedstock ratio is between 0.2 and 1 kg / kg.

[0107] In one embodiment, steam cracking step d) further comprises the treatment of all or part of a gas cut chosen from the cuts obtained in steps a), c) and e) alone or as a mixture.

[0108] In one embodiment, steam cracking step d) further comprises the treatment of all or part of the cut essentially comprising C1 and C2 hydrocarbon compounds obtained in step b).

[0109] In one embodiment, steam cracking step d) further comprises the treatment of all or part of the cut essentially comprising hydrocarbon compounds having from 4 to 6 carbon atoms (C4-C6) obtained in step g).

[0110] When the optional residue hydrotreatment step k) is implemented, the gas cut can also be chosen in step k).

[0111] When the optional naphtha hydrotreatment step i) is implemented, the gas cut can also be chosen in step i).

[0112] When the optional LCO hydrotreatment step 1) is implemented, the gas cut can also be chosen in step 1).

[0113] In one embodiment, steam cracking step d) further comprises the treatment of all or part of an LPG fraction chosen from the fractions obtained in steps a, c), e), f), k), i) and 1) alone or as a mixture.

[0114] Advantageously, when an LPG cut is treated, the residence time of the incoming charge is between 0.1 and 0.4 seconds, the temperature at the tube outlet is between 700 and 1000°C, preferably between 800 and 900°C, and the steam / charge ratio is between 0.2 and 0.8 kg / kg.

[0115] In one embodiment, steam cracking step d) further comprises the treatment of all or part of the ethane cut obtained in step f).

[0116] Advantageously, when the ethane fraction is treated, the residence time of the incoming charge is between 0.15 and 0.6 seconds, the temperature at the tube outlet is between 700 and 1000°C, preferably between 800 and 900°C, and the steam / charge ratio is between 0.1 and 0.6 kg / kg.

[0117] In one embodiment, step d) of steam cracking further comprises the treatment of all or part of the raffinate cut obtained in step f) of transformation and / or separation of the aromatics.

[0118] In one embodiment, in step d) of steam cracking, when the optional step i) of naphtha hydrotreatment is implemented, the naphtha cut is the hydrotreated naphtha cut obtained in step i) of naphtha hydrotreatment.

[0119] In one embodiment, when the optional naphtha hydrotreatment step i) is implemented, the steam cracking step d) further comprises the treatment of all or part of the hydrotreated light naphtha and / or hydrotreated heavy naphtha and / or hydrotreated LCN cut obtained in the optional naphtha hydrotreatment step i).

[0120] In one embodiment, steam cracking step d) further comprises the treatment of all or part of the naphtha cut obtained in the optional LCO hydrotreatment step 1).

[0121] In one embodiment, steam cracking step d) further comprises the treatment of all or part of the raffinate concentrated in non-aromatic compounds and C11+ aromatics obtained in the optional liquid-liquid extraction step h).

[0122] In one embodiment, steam cracking step d) further comprises the treatment of all or part of the propane cut obtained in the optional propylene recovery step j).

[0123] In one embodiment, the different cuts are treated simultaneously or preferably separately in the steam cracking unit. When they are treated separately, they are treated under different operating conditions depending on the nature of the cut to be treated.

[0124] In one embodiment, in step d) of steam cracking, a pyrolysis oil cut is also obtained. Advantageously, this pyrolysis oil cut is used for the production of a low-sulfur fuel oil (or BTS fuel oil).

[0125] In one embodiment, in step d) of steam cracking, a light pyrolysis gasoline cut is also obtained.

[0126] In one embodiment, in step d) of steam cracking, a heavy pyrolysis gasoline cut is also obtained.

[0127] In one embodiment, in step d) of steam cracking, a cut comprising H2, H2S, CO and CH4 is further obtained.

[0128] In one embodiment, in step d) of steam cracking, a C4 cut is also obtained.

[0129] In one embodiment, in step d) of steam cracking, the olefinic fraction is ethylene.

[0130] In one embodiment, in step d) of steam cracking, the olefinic fraction is propylene.

[0131] In one embodiment, in step d) of steam cracking, the olefinic fraction is butadiene.

[0132] In one embodiment, in step d) of steam cracking, the olefinic cut is butene-1.

[0133] In one embodiment, in step d) of steam cracking, the olefinic cut is butene-2.

[0134] In one embodiment, in step d) of steam cracking, the olefinic fraction is isobutene.

[0135] In one embodiment, in step d) of steam cracking, the olefinic fraction is isoprene. Step e) of catalytic reforming

[0136] The process according to the invention comprises a step e) of catalytic reforming comprising the treatment of all or part of the heavy naphtha cut obtained in step c) in a catalytic reforming unit comprising a reactor containing a reforming catalyst, operated under a pressure of between 0.1 and 25 MPa and at a temperature of between 480 and 570°C, and obtaining a reformate cut. The objective of catalytic reforming is to transform the naphthenic constituents and part of the paraffinic constituents (with a low octane number) into aromatic constituents with a high octane number. The catalytic reforming unit consists mainly of a series of three or more reactors containing one or more reforming catalysts and a separator for separating the different products at the outlet of the reactors.The catalyst used may be sensitive to the presence of sulfur and nitrogen products, which is why the inlet charge is advantageously free of sulfur, nitrogen and their derivatives.

[0137] The reaction is an endothermic reaction. The hydrocarbons of the heavy naphtha fraction (in particular paraffins and naphthenes) are transformed during this process into aromatic hydrocarbons and branched paraffins.

[0138] Advantageously, the hydrogen / hydrocarbon molar ratio of the incoming feedstock is between 0.8 and 8 mol / mol.

[0139] Advantageously, the weight hourly space velocity (WHSV) defined as being the ratio between the total mass flow rate of the treated feedstock and the total mass of catalyst of the incoming feedstock is between 0.1 and 10 h1, preferably between 0.5 and 6 h1.

[0140] Advantageously, the reforming catalyst comprises an active phase comprising at least one metal chosen from nickel, ruthenium, rhodium, palladium, iridium or platinum, and at least one promoter chosen from rhenium, tin, germanium, cobalt, nickel, iridium, rhodium or ruthenium. Preferably, the reforming catalyst comprises an active phase comprising platinum and tin. The amount of metal is between 0.02 and 2% by weight, preferably between 0.05 and 1.5% by weight, even more preferably between 0.1 and 0.8% by weight relative to the total weight of the catalyst. Preferably, the reforming catalyst comprises a support chosen from alumina, silica-alumina or silica. Preferably, the support is based on alumina.

[0141] In one embodiment, step e) of catalytic reforming further comprises the treatment of all or part of the cut essentially comprising hydrocarbon compounds having 7 carbon atoms or more (C7+) obtained in step g).

[0142] In one embodiment, step e) of catalytic reforming further comprises the treatment of all or part of the hydrotreated heavy naphtha cut obtained in the optional step i) of naphtha hydrotreatment.

[0143] In one embodiment, step e) of catalytic reforming further comprises the treatment of all or part of the naphtha cut obtained in the optional step 1) of LCO hydrotreatment.

[0144] In one embodiment, step e) of catalytic reforming further comprises the treatment of all or part of the raffinate concentrated in non-aromatic compounds and in aromatic compounds with 11 carbons and more (Cl 1+) obtained in the optional step h) of liquid-liquid extraction.

[0145] In one embodiment, in step e) of catalytic reforming, a gas cut is further obtained. Advantageously, an LPG cut can be separated from the gas cut.

[0146] In one embodiment, in step e) of catalytic reforming, a hydrogen cut is also obtained.

[0147] Step f) of transformation and / or separation of aromatics

[0148] The process according to the invention comprises a step f) of transformation and / or separation of the aromatics comprising the treatment of all or part of the reformate cut obtained in step e) in a unit for transformation and / or separation of the aromatics, and the obtaining of an aromatic cut.

[0149] The objective of this step is twofold: - Convert aromatic C9s and possibly aromatic CIOs into benzene, toluene, ortho xylene and para xylene, - Adjust the proportions of these different molecules by adjusting the number and position of the methyl substituents on the aromatic rings.

[0150] The processes advantageously used to carry out this step are described below. The judicious choice of catalysts and operating conditions advantageously makes it possible to minimize yield losses: - Less than 5% loss of methyl groups - Less than 5% loss of aromatic cycles

[0151] This step advantageously takes place within a unit comprising an aromatic complex which constitutes a set of steps of separation, purification and conversion of aromatic molecules present in the reformate.

[0152] The objective of an aromatic complex is to produce with very high purity (compatible with polymerization) benzene, para-xylene, and sometimes toluene. and ortho-xylene, as well as heavy aromatics, from aromatic-rich fractions such as reformate or pyrolysis gasoline. Advantageously, in a first step, olefins and non-aromatics are removed in units such as earth treatment, hydrogenation units, extractive distillations or liquid-liquid extraction units. Advantageously, in a second step, a separation train, composed of different distillation columns, produces benzene, toluene, an aromatics cut containing 8 carbon atoms (or A8 cut), and one or more cuts containing aromatics with more than 9 carbon atoms.

[0153] Advantageously, the A8 cut enters the “xylene loop”, in which the paraxylene is separated from the other xylene isomers either in a liquid-liquid extraction unit based on simulated moving bed (SMB) technology, or in a crystallization unit. The other constituents of the A8 cut (ortho and meta xylene, ethyl benzene) are advantageously isomerized or converted by means of a liquid-phase or gas-phase isomerization unit, and return to the separation train. All or part of the toluene is advantageously converted in transalkylation, disproportionation, or methyl-alkylation units to produce more C8 aromatics and benzene. Aromatics containing 9 or 10 carbon atoms can advantageously be sent to a transalkylation unit to produce more aromatics with 8 carbon atoms.As for the heavier aromatics (11 carbon atoms and more), they are considered by-products, and advantageously exported as gasoline base.

[0154] In one embodiment, step f) of transformation and / or separation of aromatics further comprises the treatment of all or part of the light pyrolysis gasoline cut obtained in step d) of steam cracking, preferably jointly with all or part of the reformate cut.

[0155] In one embodiment, step f) of transformation and / or separation of the aromatics further comprises a treatment of all or part of the extract concentrated in aromatic compounds of 6 to 10 carbon atoms (C6-C10) obtained in the optional step h) of liquid-liquid extraction, preferably jointly with the reformate cut.

[0156] In one embodiment, in step f) of transformation and / or separation of the aromatics, an LPG cut is also obtained.

[0157] In one embodiment, in step f) of transformation and / or separation of the aromatics, an ethane cut is also obtained.

[0158] In one embodiment, in step f) of transformation and / or separation of the aromatics, a raffinate cut is also obtained, preferably rich in paraffins.

[0159] In one embodiment, in step f) of transformation and / or separation of the aromatics, a heavy aromatic cut is also obtained. Advantageously, this heavy aromatic cut is used for the production of a low-sulfur fuel oil (or BTS fuel oil).

[0160] In one embodiment, in step f) of transformation and / or separation of the aromatics, the aromatic cut is benzene.

[0161] In one embodiment, in step f) of transformation and / or separation of the aromatics, the aromatic cut is paraxylene.

[0162] It is also possible to produce other aromatic fractions such as toluene or orthoxylene.

[0163] Step g) of oligomerization and catalytic cracking in one step (oligo-cracking)

[0164] The process according to the invention comprises a step g) of oligomerization and catalytic cracking in one stage, comprising the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained in step b) of fluid catalytic cracking in a unit of oligomerization and catalytic cracking in one stage comprising a reactor containing a catalyst allowing the oligomerization and catalytic cracking of olefins, operated at a temperature between 400 and 600°C, preferably between 450°C and 580°C, and at a pressure between 0.1 and 1 MPa, preferably between 0.1 and 0.5 MPa, and obtaining a cut essentially comprising propylene and ethylene.

[0165] In one embodiment, in step g), a cut is also obtained which essentially comprises hydrocarbon compounds having from 4 to 6 carbon atoms (C4-C6). Advantageously, all or part of the C4-C6 cut is recycled at the inlet of step g). The recycling flow rate of the C4-C6 cut obtained in step g) relative to the flow rate of the feedstock entering step g) can vary in a ratio of 1 to 5, and preferably of 2 to 4.

[0166] In one embodiment, in step g), a cut is also obtained which essentially comprises hydrocarbon compounds having 7 carbon atoms or more (C7+).

[0167] In one embodiment, step g) further comprises the treatment of all or part of the C4 cut obtained in step d) of steam cracking.

[0168] Step g) of oligomerization and catalytic cracking in one step is advantageously carried out in the presence of a catalyst allowing the oligomerization and catalytic cracking of olefins comprising a zeolite having shape selectivity, this zeolite having an Si / Al atomic ratio of between 50 and 500, and preferably of between 75 and 150.

[0169] In one embodiment, the catalyst allowing the oligomerization and the catalytic cracking of olefins comprises a shape-selective zeolite belonging to a first group consisting of one of the following structural types: MEL, MFI, NES, EUO, FER, CHA, MFS, MWW, or consisting of any mixture of the elements of this first group.

[0170] In another embodiment, the catalyst for oligomerization and catalytic cracking of olefins comprises a shape-selective zeolite belonging to a second group consisting of the following zeolites: NU-85, NU-86, NU-88 and IM-5 or any mixture of the elements of this second group.

[0171] One of the advantages of these zeolites exhibiting shape selectivity is that it leads to better propylene / isobutene selectivity, i.e. a higher propylene / isobutene ratio in the effluents of said single-stage oligomerization and catalytic cracking unit.

[0172] The zeolite used in the catalyst allowing the oligomerization and catalytic cracking of olefins can be dispersed in a matrix based on silica, zirconia, alumina or silica alumina, the proportion of zeolite generally being between 15% and 90% by weight, preferably between 30% and 80% by weight.

[0173] In particular, one of the following commercial ZSM-5 zeolites can be used:

[0174] - CBV 28014 (Si / Al ratio: 140), and CBV 1502 (Si / Al atomic ratio: 75) of Zeolyst International, Valley Forge PA, 19482 USA,

[0175] - ZSM-5 Pentasil with an atomic ratio of Si / Al 125 from Süd-Chemie (Munich, Germany).

[0176] The catalyst allowing the oligomerization and catalytic cracking of olefins is generally used in a moving bed, preferably in the form of beads with a diameter generally between 1 mm and 3 mm.

[0177] The catalyst allowing the oligomerization and catalytic cracking of olefins can also be used in a fixed bed, in which case the reactor used is alternately in the reaction phase then in the regeneration phase.

[0178] The regeneration phase typically comprises a combustion phase of the carbon deposits formed on the catalyst, for example using an air / nitrogen mixture or oxygen-depleted air (for example by recirculation of fumes), or simply air.

[0179] According to one embodiment, the regeneration of the catalyst allowing the oligomerization and catalytic cracking of olefins is carried out at a temperature between 400°C and 650°C, and at a pressure advantageously close to the pressure used for the oligomerization and catalytic cracking reaction in one step.

[0180] Advantageously, step g) is carried out at a WH of between 1 h 1 and 10 h 1.

[0181] Step g) comprises the treatment of the olefins contained in the LPG cuts and FCC gasoline obtained in step b) of fluid catalytic cracking, i.e. the LPG and FCC gasoline cuts can be sent directly to the single-stage oligomerization and catalytic cracking unit or can undergo one or more treatment / transformation steps upstream of the single-stage oligomerization and catalytic cracking step.

[0182] In one embodiment, step g) of oligomerization and one-step catalytic cracking comprises the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained in step b) of fluid catalytic cracking by sending all or part of said LPG and FCC gasoline cuts into a one-step oligomerization and catalytic cracking unit.

[0183] In one embodiment, when an embodiment of the optional naphtha hydrotreatment step i) is implemented, the one-step oligomerization and catalytic cracking step g) comprises the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained in the fluid catalytic cracking step b) by sending all or part of the LPG cut obtained in the fluid catalytic cracking step b) and all or part of the selectively hydrogenated light FCC gasoline (LCN) cut obtained in step i) into a one-step oligomerization and catalytic cracking unit.

[0184] In one embodiment, when the optional propylene recovery step]) is implemented, the one-step oligomerization and catalytic cracking step g) comprises the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained in the fluid catalytic cracking step b) by sending all or part of the C4 cut obtained in step j) and all or part of the FCC gasoline cut obtained in the fluid catalytic cracking step b) to a one-step oligomerization and catalytic cracking unit.

[0185] In one embodiment, when an embodiment of the optional naphtha hydrotreatment step i) and the optional propylene recovery step j) are implemented, the one-step oligomerization and catalytic cracking step g) comprises the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained in the fluid catalytic cracking step b) by sending all or part of the C4 cut obtained in step j) and all or part of the selectively hydrogenated light FCC gasoline (LCN) cut obtained in step i) into a one-step oligomerization and catalytic cracking unit.

[0186] An example of a one-step oligomerization and catalytic cracking process is the Olicrack™ process marketed by Axens. Optional steps Step h) liquid-liquid extraction

[0187] In one embodiment, the process according to the invention further comprises a liquid-liquid extraction step h) comprising the treatment of a portion of the FCC gasoline cut obtained in step b) of fluid catalytic cracking, or in one embodiment of the hydrotreated heavy FCC gasoline cut (HCN) obtained in the optional step i), in a liquid-liquid extraction unit, and obtaining an extract concentrated in aromatic compounds of 6 to 10 carbon atoms (C6-C10) and a raffinate concentrated in non-aromatic compounds and in aromatic compounds with 11 carbons and more (C11+).

[0188] The term "concentrated in" means a content of at least 95% by weight, preferably at least 99% by weight, very preferably at least 99.5% by weight of desired compounds.

[0189] According to one embodiment, the liquid-liquid extraction unit comprises the following steps / devices:

[0190] - extraction by means of a liquid-liquid extractor fed with solvent flow to separate the raffinate and the extract,

[0191] - water washing of the raffinate with a water washing tower,

[0192] - water stripping with a water stripping section,

[0193] - stripping the extract with an extract stripping section,

[0194] - separation of aromatics with recovery tower to separate the extract and the flow of solvent, and

[0195] - solvent regeneration with a solvent regeneration section.

[0196] According to one or more embodiments, the solvent comprises a compound selected from ethylene glycol, diethylene glycol, triethylene glycol, hexamethylphosphoramide, propylene carbonate, ethylene carbonate, sulfolane, 3-methylsulfolane, N-methylacetamide, N,N-dimethylacetamide, butyrolactone, 1-methylpyrrolidone, dimethylsulfoxide, caprolactam, N-methylformamide, pyrrolidin-2-one, furfural, 1,1,3,3-tetramethylurea and a mixture thereof. According to one embodiment, the solvent comprises or consists of sulfolane.

[0197] According to one embodiment, the solvent consists of at least 90% by weight, preferably at least 95% by weight (eg at least 99% by weight), sulfolane, relative to the total weight of the solvent. According to one embodiment, the solvent further comprises an anti-solvent, such as water. According to one embodiment, the solvent comprises between 0.01% by weight and 5% by weight, preferably between 0.1% by weight and 3% by weight (eg between 0.5% by weight and 2% by weight) of anti-solvent, such as water, relative to the total weight of the solvent.

[0198] According to one embodiment, the liquid-liquid extraction unit is operated at a pressure of between 0.05 and 3 MPa, preferably between 0.1 and 2 MPa, preferably between 0.2 and 1.5 MPa, preferably between 0.3 and 1 MPa, such as at 0.65 ± 0.2 MPa, by example when the solvent includes sulfolane.

[0199] According to one embodiment, the liquid-liquid extraction unit is operated at a temperature between 10 and 150°C, preferably between 15 and 120°C, preferably between 20 and 100°C, preferably between 30 and 90°C, such as 54 ±5°C, for example when the solvent comprises sulfolane.

[0200] According to one embodiment, the solvent / filler ratio is between 2 and 10, preferably between 4 and 8. Step i) naphtha hydrotreatment

[0201] In one embodiment, the process according to the invention further comprises a step i) of hydrotreatment of naphtha comprising the treatment of all or part of a naphtha cut and / or FCC gasoline chosen from the cuts obtained in steps a) and b) alone or as a mixture in a hydrotreatment unit comprising a reactor containing a hydrotreatment catalyst, operated in the presence of hydrogen, at a temperature of between 200°C and 400°C, preferably between 250°C and 370°C, under a pressure of between 0.2 MPa and 2.5 MPa, preferably between 0.5 MPa and 2.0 MPa, and obtaining a hydrotreated naphtha cut and / or hydrotreated FCC gasoline.

[0202] Advantageously, step i) is carried out at an incoming load WH of between 1 h 1 and 10 h *, preferably between 4 h 1 and 8 h '.

[0203] Advantageously, step i) is carried out at a hydrogen volume coverage relative to the incoming charge volume of between 100 and 350 Nm3 / m3 of liquid charge, preferably between 170 and 300 Nm3 / m3.

[0204] The optional naphtha hydrotreatment step advantageously allows the elimination of sulfur (hydrodesulfurization), and / or the elimination of nitrogen (hydrodenitrogenation or hydrodenitration) which are poisons for the catalysts used in downstream units such as the catalytic reforming unit for example.

[0205] The operating conditions used in step i) advantageously make it possible to carry out hydrotreatment of the feedstock so as to achieve an organic nitrogen content in the effluent of less than 1 ppm by weight.

[0206] The operating conditions used in step i) advantageously make it possible to carry out hydrotreatment of the feedstock so as to achieve a sulfur content in the effluent of less than 1 ppm by weight.

[0207] Advantageously, the hydrotreatment catalyst is chosen from among the conventional hydrotreatment catalysts known to those skilled in the art.

[0208] Preferably, the catalyst comprises a hydrogenating function composed of one or more metals from group VIB and one or more metals from group VIIIB, taken alone or as a mixture, said catalyst being a catalyst having a sulfide phase as active phase.

[0209] The metal(s) from group VIB are advantageously chosen from chromium, molybdenum and tungsten, alone or as a mixture and preferably chosen from molybdenum and tungsten. Preferably, the content of metal from group VIB in the hydrotreatment catalyst(s) is advantageously between 5 and 40% by weight and preferably between 7 and 30% by weight, very preferably between 10 and 28% by weight, the percentages being expressed as percentage by weight of oxides.

[0210] The metal(s) from group VIII are advantageously chosen from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum, and preferably from cobalt or nickel. Preferably, the content of metal from group VIII in the hydrotreatment catalyst(s) is advantageously between 0.5 and 15% by weight and preferably between 1.5 and 10% by weight, the percentages being expressed as percentage by weight of oxides.

[0211] The hydrotreatment catalyst may also advantageously comprise at least one promoter element deposited on said catalyst selected from the group formed by phosphorus, boron and silicon, optionally one or more elements from group VIIA (chlorine and fluorine preferred), optionally one or more elements from group VIIB (manganese preferred), and optionally one or more elements from group VB (niobium preferred). The concentration of said promoter is advantageously less than 20% by weight, and preferably less than 10% by weight relative to the weight of the catalyst.

[0212] Advantageously, the catalyst may further contain one or more adjuvant additives leading to better dispersion and promotion of the active phase of the catalyst, so as to improve its activity. Said additives are typically one or more organic compounds containing oxygen and / or one or more organic compounds containing nitrogen and / or one or more organic compounds containing sulfur. When present, the total content of organic compound(s) containing oxygen and / or nitrogen and / or sulfur present in the catalyst is generally between 1 and 30% by weight, preferably between 1.5 and 25% by weight, and more preferably between 2 and 20% by weight relative to the total weight of the catalyst.

[0213] Preferably, the hydrotreatment catalyst is supported on a support chosen from alumina, silica alumina, and preferably on alumina.

[0214] In one embodiment, in step i) of naphtha hydrotreatment, when the optional step k) of residue hydrotreatment is implemented, the naphtha cut can also be chosen in step k).

[0215] In one embodiment, in step i) of naphtha hydrotreatment, the naphtha cuts are treated jointly or separately in the same hydrotreatment section, or separately in separate sections.

[0216] Advantageously, step i) of naphtha hydrotreatment comprises the treatment of all or part of the naphtha cuts from steps a) of atmospheric distillation and optionally k) of residue hydrotreatment in a first hydrotreatment section i-S1), and the treatment of all or part of the FCC gasoline cut obtained in step b) of fluid catalytic cracking in a second hydrotreatment section i-S2). This configuration makes it possible to separately treat the FCC gasoline comprising aromatics that can be recovered in step h) of liquid-liquid extraction without diluting them with a naphtha cut comprising few aromatics.

[0217] In a preferred embodiment, the treatment of all or part of the naphtha cuts from steps a) of atmospheric distillation and optionally k) of residue hydrotreatment in the first hydrotreatment section i-S1) is followed by a step of separating the hydrotreated naphtha cut to obtain a hydrotreated light naphtha cut and / or a hydrotreated heavy naphtha cut.

[0218] In a preferred embodiment, the treatment of all or part of the FCC gasoline cut obtained in step b) of fluid catalytic cracking in the hydrotreatment section i-S2) comprises a step of selective hydrogenation of the diolefins to olefins followed by a separation step to obtain a selectively hydrogenated FCC light gasoline cut (LCN) essentially comprising olefins and a FCC heavy gasoline cut (HCN). The HCN cut can then advantageously undergo a step of hydrogenation of the olefins to paraffins and removal of sulfur (hydrodesulfurization) and / or removal of nitrogen (hydrodenitration or hydrodenitration) followed by a separation step to obtain a hydrotreated FCC light gasoline cut (LCN) and / or a hydrotreated FCC heavy gasoline cut (HCN).In this embodiment, the hydrotreated FCC gasoline cut is therefore either the selectively hydrogenated LCN cut, or the hydrotreated LCN cut, or the hydrotreated HCN cut.

[0219] In one embodiment, in step i) of hydrotreatment, a gas cut is further obtained. Advantageously, an LPG cut can be separated from the gas cut. Step j) of propylene recovery

[0220] In one embodiment, the method further comprises a step j) of recovering propylene comprising the treatment of all or part of the LPG cut obtained in step b) of fluid catalytic cracking in a propylene recovery unit, and obtaining a C4 cut, a propane cut and a propylene cut at polymer grade, i.e. comprising more than 99.5% by weight of propylene.

[0221] The propylene recovery unit allows the separation of the different components according to their relative volatility. A first column, the depropanizer, allows the recovery of a C4 cut at the bottom of the column, and at the top of the column a flow comprising mainly propane and propylene. This flow is then sent to a second column, the deethanizer. The flow at the top of the deethanizer (C2- cut), can be returned either to the fluid catalytic cracking step b) or to the ethylene recovery step m) depending on the composition of this stream. The column bottom of the deethanizer is sent to a third column, the C3 separator, where the propane / propylene separation takes place. The separations advantageously take place under a pressure of between 0.1 and 25 MPa as well as at a high temperature of between 100 and 150°C.

[0222] Advantageously, the incoming feed of the second column is treated in a caustic wash in order to remove certain contaminants, such as carbonyl sulfide. Step k) of residue hydrotreatment

[0223] In one embodiment, the process according to the invention further comprises a step k) of residue hydrotreatment comprising the treatment of all or part of the atmospheric residue cut obtained in step a) in a hydrotreatment unit comprising a reactor containing a hydrotreatment catalyst, operated in the presence of hydrogen, at a temperature of between 300°C and 500°C, preferably between 350°C and 430°C, under a pressure of between 5 MPa and 35 MPa, preferably between 11 MPa and 26 MPa, and obtaining a hydrotreated atmospheric residue cut.

[0224] Advantageously, step k) is carried out at an incoming load WH of between 0.1 h 1 and 5 h 1, preferably between 0.1 h 1 and 3 h 1.

[0225] Advantageously, step k) is carried out at a volume coverage of hydrogen relative to the volume of the charge of between 100 and 5000 Nm3 / m3, preferably between 200 and 2000 Nm3 / m3.

[0226] The optional step of hydrotreatment of all or part of the atmospheric residue cut is advantageously carried out in one or more reactors, preferably fixed bed reactors arranged in series, and advantageously allows in the first reactor(s) the elimination of metals (hydrodemetallization: HDM) as well as part of the elimination of sulfur (hydrodesulfurization: HDS), a so-called HDM step, and in the last reactor(s) the deep refining of the feedstock, in particular hydrodesulfurization, a so-called HDS step. The effluents are withdrawn from the last HDS reactor.

[0227] This step advantageously makes it possible to avoid poisoning the catalysts used in the downstream units, in particular in step b) of fluid catalytic cracking.

[0228] The HDM step is preferably implemented when the feed contains more than 50 ppm, or even more than 100 ppm of metals and / or when the feed includes impurities likely to cause too rapid clogging of the catalytic bed, such as iron or calcium derivatives for example. The aim is to reduce the impurity content and thus protect the downstream HDS step from deactivation and clogging. It can be implemented in permutable reactors.

[0229] In one embodiment, the hydrotreating catalyst comprises an HDM catalyst and / or an HDS catalyst.

[0230] For the HDM step, the ideal catalyst must be capable of treating feedstocks that may be rich in asphaltenes, while having a high demetallizing power associated with a high metal retention capacity and high resistance to coking. The HDM catalyst advantageously has the following characteristics:

[0231] - Demetallization rate of at least 10% to 90% in the HDM step;

[0232] - Metal retention capacity greater than 10% relative to the weight of ca new catalytic converter, which allows for longer operating cycles;

[0233] - High resistance to coking even at temperatures above 390°C which contributes to the extension of the duration of cycles often limited by the increase in pressure drop and loss of activity due to coke production, and which allows the majority of thermal conversion to be carried out in this stage.

[0234] For the HDS stage, the ideal catalyst must have a strong hydrogenating power in order to achieve deep refining of the products: desulfurization, continued demetallization, lowering of the Conradson carbon and possibly of the asphaltene content.

[0235] The HDM and HDS catalysts may be any catalysts known to those skilled in the art for carrying out HDM and HDS steps. They may be granular catalysts comprising, on a support, at least one metal or metal compound having a hydro / dehydrogenating function. These catalysts may advantageously be catalysts comprising a metal from group VIII, generally chosen from the group consisting of nickel and cobalt, and / or a metal from group VIB, preferably molybdenum and / or tungsten. For example, a catalyst comprising from 0.5% to 10% by weight of nickel, preferably from 1% to 5% by weight of nickel (expressed as nickel oxide NiO), and from 1% to 30% by weight of molybdenum, preferably from 3% to 20% by weight of molybdenum (expressed as molybdenum oxide MoO3) relative to the total weight of the catalyst, on a mineral support, may be used.The mineral support may, for example, be chosen from the group consisting of alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals. Advantageously, the mineral support may contain other doping compounds, in particular oxides chosen from the group consisting of boron oxide, zirconia, ceria, titanium oxide, phosphoric anhydride and a mixture of these oxides. An alumina support is most often used and very often an alumina support doped with phosphorus and possibly boron. When phosphoric anhydride P2O5 is present, its concentration is less than 10% by weight relative to the weight of the support. When boron trioxide B2O5 is present, its concentration is less than 10% by weight relative to the weight of the support. Alumina. used can be a y (gamma) or q (eta) alumina. The catalysts are most often in the form of extrudates. The total content of metal oxides from groups VIB and VIII can be from 3% to 40% by weight, preferably from 5% to 30% by weight relative to the total weight of catalyst, and the weight ratio expressed as metal oxide between metal (or metals) from group VIB and metal (or metals) from group VIII is generally between 20 and 1, and most often between 10 and 2.

[0236] Catalysts that can be used in the HDM step are for example described in documents EP0113297, EP0113284, US5221656, US5827421, US7119045, US5622616 and US 5089463.

[0237] Catalysts that can be used in the HDS step are for example described in patent documents EP0113297, EP0113284, US6589908, US4818743 or US6332976.

[0238] An example of an atmospheric residue hydrotreatment process is the Hyvahl™ process marketed by Axens.

[0239] In one embodiment, in step k) of residue hydrotreatment, a gas cut is further obtained. Advantageously, an LPG cut can be separated from the gas cut.

[0240] In one embodiment, in step k) of residue hydrotreatment, a naphtha cut is further obtained.

[0241] In one embodiment, in step k) of residue hydrotreatment, a diesel cut is further obtained. Step 1) hydrotreatment of LCO

[0242] In one embodiment, the process according to the invention further comprises a step 1) of hydrotreatment of LCO comprising the treatment of all or part of the LCO cut obtained in step b) of fluid catalytic cracking, in a hydrotreatment unit comprising a reactor containing a hydrotreatment catalyst, operated in the presence of hydrogen, at a temperature between 340°C and 420°C, under a pressure between 3 MPa and 12 MPa, and obtaining a hydrotreated LCO cut.

[0243] Advantageously, step 1) is carried out at an incoming load WH of between 0.5 h 1 and 4 h 1.

[0244] Advantageously, step 1) is carried out at a hydrogen volume coverage relative to the incoming charge volume of between 100 and 1800 Nm3 / m3 of liquid charge.

[0245] The optional hydrotreatment step 1) advantageously allows the hydrogenation of aromatics (in order to possibly allow the cracking of the hydrotreated LCO cut in step b) of fluid catalytic cracking), as well as the elimination of sulfur (hydrodesulfurization), and / or the elimination of nitrogen (hydrodenitrogenation or hydrode- nitration).

[0246] The hydrotreatment catalyst is advantageously chosen from among the conventional hydrotreatment catalysts known to those skilled in the art. It generally comprises a porous mineral support, one or more metals or compounds of metals from group VIII (this group including in particular cobalt, nickel, iron, etc.) and one or more metals or compounds of metals VIB (this group including in particular molybdenum, tungsten, etc.).

[0247] The sum of the metal(s) or metal compound(s), expressed as weight of metal relative to the total weight of the catalyst, is advantageously between 0.5 and 50% by weight. The sum of the metal(s) or metal compound(s) from group VIII, expressed as weight of metal relative to the weight of the catalyst, is advantageously between 0.5 and 15% by weight, preferably between 1 and 10% by weight. The sum of the metal(s) or metal compound(s) from group VIB, expressed as weight of metal relative to the weight of the catalyst, is advantageously between 2 and 50% by weight, preferably between 5 and 40% by weight.

[0248] The porous mineral support may comprise, in a non-limiting manner, one of the following compounds: alumina, silica, zirconia, titanium oxide, magnesia, or two compounds chosen from the preceding compounds, for example silica-alumina or alumina-zirconia, or alumina-titanium oxide, or alumina-magnesia, or three or more compounds chosen from the preceding compounds, for example silica-alumina-zirconia or silica-alumina-magnesia. The support may also comprise, in part or in whole, a zeolite. Preferably, the catalyst comprises a support composed of alumina, or a support composed mainly of alumina (for example from 80 to 99.99% by weight of alumina). The porous support may also comprise one or more other promoter elements or compounds, based for example on phosphorus, magnesium, boron, silicon, or comprising a halogen.The support may for example comprise a content of 0.01 to 20% by weight of B2O3, or of SiO2, or of P2O5, or of a halogen (for example chlorine or fluorine), or a content of 0.01 to 20% by weight of a combination of several of these promoters. Common catalysts are for example catalysts based on cobalt and molybdenum, or nickel and molybdenum, or nickel and tungsten, on an alumina support, this support being able to comprise one or more promoters as previously mentioned.

[0249] In one embodiment, in step 1) of LCO hydrotreatment, a gas cut is further obtained. Advantageously, an LPG cut can be separated from the gas cut.

[0250] In one embodiment, in step 1) of hydrotreatment of LCO, a naphtha cut is further obtained.

[0251] Step m) of recovery and purification of ethylene

[0252] In one embodiment, the method further comprises a step m) of recovery and purification of ethylene comprising the treatment of all or part of the cut essentially comprising C1 and C2 hydrocarbon compounds (C1-C2 cut) resulting from step b) of fluid catalytic cracking in an ethylene recovery unit (Ethylene Recovery Unit or ERU according to English terminology), and obtaining a cut comprising dihydrogen, methane and nitrogen, and an ethylene cut at polymer grade, i.e. comprising more than 99.5% by weight of ethylene.

[0253] Advantageously, before sending all or part of the C1-C2 cut to distillation columns making it possible to separate the compounds according to their relative volatility, it passes through a purification train in order to remove a significant number of impurities, including in particular oxygenates (Nox and O2), dienes, acetylene but also sulfur and sulfur compounds, water, arsenic and mercury.

[0254] This purification of the C1-C2 cut makes it possible, among other things, to meet the specifications on these compounds at the input of the separation part of this stage, due to the need for a cold box for optimal operation of the distillation columns.

[0255] The C1-C2 cut is sent to a cold box allowing at least two outputs to be obtained: a cut, comprising a mixture of Cl and H2, and a cut comprising Cl and C2 compounds sent to a demethanizer. This allows at least two cuts to be obtained: a methane cut at the top and a C2 cut comprising ethane and ethylene at the bottom of the column. The C2 cut is then sent to a C2 separator, allowing an ethylene cut at polymer grade to be obtained at the top of the column and an ethane cut at the bottom of the column, combined with the cut comprising a mixture of Cl and H2 at the top of the cold box.

[0256] Concerning the purification part, the operating conditions are advantageously the following: temperature between 30°C and 300°C, and preferably between 40°C and 260°C; pressure between 0.1 and 5 MPa, preferably between 0.5 and 3 MPa and more preferably between 1 and 2 MPa,

[0257] Concerning the fractionation part, the operating conditions are advantageously the following: temperature between -120°C and 100°C, and preferably between -100°C and 50°C; pressure between 0.1 and 5 MPa, preferably between 0.5 and 3.5 MPa. It should be noted that the operating conditions are specifically defined for each of the separation steps described above.

[0258] In one embodiment, the cut comprising a mixture of Cl and H2 and / or the ethane cut, obtained in step m) is sent to step d) of steam cracking. DESCRIPTION OF THE FIGURES

[0259] [Fig.l]: A crude oil feedstock 1 is sent to a stage a) of atmospheric distillation to obtain a naphtha cut 3, a diesel cut 4 and an atmospheric residue cut 5. Cut 5 is sent to a stage b) of fluid catalytic cracking to obtain an LPG cut 46, an FCC gasoline cut 11 and an LCO cut 12. Cuts 4 and 12 are sent to a stage c) of hydrocracking to obtain a light naphtha cut 15, and a heavy naphtha cut 16. Cut 11 is sent to a stage g) of oligomerization and catalytic cracking in one stage to obtain a cut comprising essentially propylene and ethylene 51. Cuts 3, 15, 51 and possibly a part of cut 16 are sent to a stage d) of steam cracking to obtain an olefinic cut (40 ethylene, or 41 propylene, or 42 butadiene). Part or all of the cut 16 is sent to a catalytic reforming step e) to obtain a reformate cut 32.The 32 cut is sent to a step f) of transformation and / or separation of the aromatics to obtain an aromatic cut (36 benzene, or 37 paraxylene).

[0260] [Fig.2]: A crude oil feedstock 1 is sent to an atmospheric distillation step a) to obtain a gas cut 2, a naphtha cut 3, a diesel cut 4 and an atmospheric residue cut 5. Cut 5 is sent to a residue hydrotreatment step k) to obtain a gas cut 6, a naphtha cut 7, a diesel cut 8 and a hydrotreated atmospheric residue cut 9. Cut 9 is sent to a fluid catalytic cracking step b) to obtain a cut comprising essentially C1 and C2 hydrocarbon compounds 10, an LPG cut 46, an FCC gasoline cut 11, an LCO cut 12 and a heavy oil cut 13. The LPG cut 46 is sent to a propylene recovery step j) to obtain a propane cut 50, a propylene cut 49 and a C4 cut 48.At least a portion of cut 4 is sent to a first hydrocracking section c-S1) to obtain a gas cut 14, a light naphtha cut 15, a heavy naphtha cut 16 and a purge cut 17. At least a portion of cut 4, cut 8 and cut 12 are sent to a second hydrocracking section c-S2) to obtain a gas cut 23, a light naphtha cut 24, a heavy naphtha cut 25 and a purge cut 26. Cuts 3 and 7 are sent to a first naphtha hydrotreatment section i-S1) to obtain a gas cut 27, a hydrotreated light naphtha cut 28 and a hydrotreated heavy naphtha cut 29. Cut 11 is sent to a second naphtha hydrotreatment section i-S2) to obtain a selectively hydrogenated LCN cut 47, a hydrotreated LCN cut 48 and a purge cut 49. 19, a gas cut 18, and a hydrotreated HCN cut 20.Cut 20 is sent to a liquid-liquid extraction step h) to obtain an extract concentrated in aromatic compounds of 6 to 10 carbon atoms (C6-C10) 21 and a raffinate concentrated in non-aromatic compounds and in aromatic compounds with 11 carbons and more (Cl 1+) 22. Cuts 47 and 48 are sent to . a step g) of oligomerization and catalytic cracking in one step to obtain a cut essentially comprising propylene and ethylene 51, a cut essentially comprising hydrocarbon compounds having from 4 to 6 carbon atoms (C4-C6) 52 and a cut essentially comprising hydrocarbon compounds having 7 carbon atoms and more (C7+) 53. A portion of the cut 52 is recycled at the inlet of step g). Cuts 16, 22, 25, 29 and 53 are sent to a step e) of catalytic reforming to obtain a hydrogen cut 30, a gas cut 31, and a reformate cut 32.Cuts 2, 6, 10, 14, 18, 23, 27, 31, 50, 51, 15, 24, 28, 19 and the other part of cut 52 are sent to a steam cracking step d) to obtain a cut 39 comprising H2, H2S, CO and CH4, an olefinic cut (40 ethylene, or 41 propylene, or 42 butadiene), a light pyrolysis gasoline cut 43, a heavy pyrolysis gasoline cut 44 and a pyrolysis oil cut 45. Cut 44 is sent to the first hydrocracking section c-S1). Cuts 21, 32 and 43 are sent to a stage f) of transformation and / or separation of aromatics to obtain an ethane cut 33, an LPG cut 34, a raffinate cut 35, an aromatic cut (36 benzene, or 37 paraxylene), and a heavy aromatic cut 38. Cuts 33, 34 and 35 are sent to stage d) of steam cracking.

[0261] [Fig.3]: The diagram in [Fig.3] is identical to that in [Fig.3], except that in step d) of steam cracking, a C4 54 cut is further obtained which is sent to step g) of oligomerization and catalytic cracking in one step. EXAMPLES

[0262] Example 1: Method according to the embodiment of [Fig.2]_;

[0263] The example below illustrates a particular implementation of the method according to the invention without limiting its scope.

[0264] The heavy hydrocarbon feedstock 1 treated in the process is a crude oil originating from the Middle East and having the properties indicated in the table below.

[0265] [Tables 1] Sulphur content % m / m 2.38 Density kg / m3 870 Asphaltene content C7 % m / m 3.43 Ni+V content ppm 49 Content of compounds boiling above 540°C % m / m 27.65

[0266] The feedstock is subjected to a step a) of atmospheric distillation, the cuts obtained are described in the table below.

[0267] [Tables2] Cut Name Gas Naphtha Diesel Atmospheric Residue Stream Number 2 3 4 5 Initial Boiling Point (°C) 30 175 350 End Boiling Point (°C) 30 175 350

[0268] The atmospheric residue cut 5 is sent to step k) of residue hydrotreatment in five fixed bed reactors in series and in the presence of different hydrotreatment catalysts (hydrodemetallation catalyst, transition catalyst and hydrodesulfurization catalyst) in a fixed bed of the CoMoNi on Alumina type under the conditions indicated in the table below.

[0269] [Tables3] Hydroconversion reactor temperature °C 370 Reactor pressure MPa 15 H2 / HC (Hydrogen volume coverage relative to feed volume) NmW 1000 WH reactors (feed volume flow rate / reactor volume) h1 0.166

[0270] A hydrotreated atmospheric residue cut 9 obtained in step k) of residue hydrotreatment is sent to a step b) of fluid catalytic cracking in the presence of a zeolitic catalyst on alumina under the conditions indicated in the table below.

[0271] [Tables4] Catalytic cracking zone outlet temperature °C 590 Catalytic cracking zone inlet pressure (absolute) MPa 0.24 Catalyst residence time in catalytic cracking zone s 1.8 Catalyst / Hydrocarbon feed ratio wt / wt 20.8

[0272] A part of the diesel cut 4 from atmospheric distillation a) and the cut pyrolysis gasoline 44 from step d) of steam cracking are sent to step c) of fixed bed hydrocracking in a first section c-Sl) carried out under the conditions presented in the following table.

[0273] [Tables5] Hydrotreatment temperature RI °C 355 Hydrocracking temperature R2 and R3 °C 365 and 340 respectively Hydrogen Partial Pressure (absolute) MPa 8 H2 / HC (Hydrogen volume coverage relative to the feed volume) NmVm3 600 WH hydrotreatment catalyst h1 2.4 WH hydrocracking catalyst R2 and R3 h1 2.0 and 4.5 respectively Hydrotreatment catalyst NiMo on Alumina Hydrocracking catalyst NiW on Alumina + zeolite

[0274] The fractionation part of step c-S1) separates the light naphtha cut and the heavy naphtha cut considering a cut point at 65°C.

[0275] At the end of steps a), k) and b), the diesel and LCO cuts 4, 8 and 12 respectively obtained are sent, in part for cut 4, and in full for cuts 8 and 12, to a fixed bed hydrocracking step c) in a second section c-S2) carried out under the conditions presented in the following table.

[0276] [Tableauxô] Hydrotreatment temperature RI °C 355 Hydrocracking temperature R2 and R3 °C 370 and 340 respectively Hydrogen Partial Pressure (absolute) MPa 10 H2 / HC (Hydrogen volume coverage relative to the feed volume) NmW 1100 WH hydrotreatment catalyst h1 1.8 WH hydrocracking catalyst R2 and R3 h1 1.4 and 3.7 respectively Hydrotreatment catalyst NiMo on Alumina Hydrocracking catalyst NiW on Alumina + zeolite

[0277] The fractionation part of step c-S2) separates the light naphtha cut and the heavy naphtha cut considering a cut point at 65°C.

[0278] The naphtha cut 3 from atmospheric distillation step a) and a naphtha cut 7 from residue hydrotreatment step k) are sent to a first fixed-bed hydrotreatment section i-Sl) under the conditions indicated in the following table.

[0279] [Tables7] Temperature °C 280-330 Partial Pressure of Hydrogen (absolute) MPa 1.4 H2 / HC (Hydrogen volume coverage relative to the charge volume) NmW 250 WH hydrotreatment catalyst h1 6

[0280] The fractionation part of step i-Sl) separates the hydrotreated light naphtha cut and the hydrotreated heavy naphtha cut considering a cut point at 65°C.

[0281] The FCC 11 gasoline cut from fluid catalytic cracking step b) is sent to a second fixed-bed hydrotreatment section i-S2) composed of a first reactor for selective hydrogenation of diolefins and then a second reactor for hydrogenation of olefins, the conditions of which are indicated in the table below.

[0282] [Tables8] Temperature RI / R2 °C 120 / 260 Pressure R1 / R2 (absolute) MPa 2.1 / 2.1 H2 / HC R1 / R2 (Hydrogen volume coverage relative to the charge volume) NmW 5 / 300 WH catalyst R1 / R2 h1 4 / 4

[0283] The fractionation part of step i-S2) separates the hydrotreated LCN cut and the hydrotreated HCN cut considering a cutting point at 65°C.

[0284] The GPL 46 cut obtained in step b) of fluid catalytic cracking is sent to a step j) of propylene recovery.

[0285] The selectively hydrogenated LCN cut 47 and the C4 cut 48 obtained respectively in steps i-S2) and j) are sent to a step g) of oligomerization and catalytic cracking in one step under the conditions indicated in the table below.

[0286] [Tables9] Reactor Temperature °C 540 Regenerator Temperature °C 480 Reactor Pressure (absolute) MPa 0.25 Catalyst - ZSM-5 Zeolite on Silica / Alumina Olefin Partial Pressure MPa 0.06 - 0.08 WH h1 12

[0287] The recycle flow rate of the cut essentially comprising hydrocarbon compounds having from 4 to 6 carbon atoms (C4-C6) 52 from the single-stage oligomerization and catalytic cracking unit g), relative to the flow rate of the feed entering said unit, is 2.

[0288] The hydrotreated HCN cut 20 from unit i-S2) is sent to a liquid-liquid extraction step h) of the C6-C10 aromatic compounds, the conditions of which are indicated in the table below.

[0289] [TableauxlO] Solvent - Sulfolane Solvent / Charge Ratio - 4 Extraction temperature °c 55 Hydrocarbon charge at the bottom of the extraction column % weight 25

[0290] The heavy naphtha cuts 16, 25, 29 and the raffinate cut concentrated in non-aromatic compounds and in Cl 1+ 22 resulting respectively from the hydrocracking stages c) in the hydrotreatment sections c-S1) and c-S2), i-S1) and h) of liquid-liquid extraction are sent to a catalytic reforming stage e), and treated under the conditions set out in the following table.

[0291] [Tableauxll] Conversion of C7 paraffins to aromatics % weight 71.2 WHSV (Weight Hourly Space Velocity) h1 2.0 H2 / HC molar ratio mol / mol 2.20 WAIT aromatization °C 535 Coke rate % weight 4.9

[0292] WAIT = weighted-average inlet temperature according to Anglo-Saxon terminology or weighted average temperature at the entrance to the reforming stage.

[0293] The concentrated extract of C6-C10 aromatic compounds 21 from the liquid-liquid extraction step h), the reformate cut 32 from the catalytic reforming step e) and the light pyrolysis gasoline cut 43 from the steam cracking step d) are sent to the aromatics transformation and / or separation step f).

[0294] The light naphtha cuts 15, 24, 28, the hydrotreated LCN cut 19 and at least a portion of the cut 52 originating respectively from the stages c) of fixed bed hydrocracking in sections c-S1) and c-S2), hydrotreatment i-S1) and i-S2) and oligomerization and one-stage catalytic cracking g), the gas cuts 2, 6, 14, 23, 18, 27, 31, the cut essentially comprising C1 and C2 hydrocarbon compounds 10, the propane cut 50 and the cut essentially comprising propylene and ethylene 51, originating respectively from the stages a) of atmospheric distillation, k) of residue hydrotreatment, b) of fluid catalytic cracking, hydrocracking in sections c-S1) and c-S2) and hydrotreatment in sections i-S1) and i-S2), catalytic reforming e), fluid catalytic cracking b) propylene recovery j) and oligomerization and one-step catalytic cracking g), and an ethane cut 33,an LPG cut 34 and a paraffin-rich raffinate cut 35 from step f) of transformation and / or separation of aromatics are sent to a steam cracking step d) where each of the cuts is cracked under different conditions set out in the following table.,

[0295] [Tablesl2] Charge Residence time (s) Pyrolysis furnace outlet temperature (°C) Steam / charge ratio (kg / kg) Ethane 0.35 850 0.3 LPG, Gas, C1-C2, Propane or C4-C6 0.22-0.35 850 0.3-0.4 Light naphtha, hydrotreated LCN or Raffinate 0.2 850 0.45-0.6

[0296] The entirety of the pyrolysis oil cut 45 obtained in step d) of steam cracking, a part of the diesel cut 4 from atmospheric distillation a), the heavy oil cut 13 from step b) of fluid catalytic cracking, and the purge cuts 17 and 26 from the hydrocracking units c-S1) and c-S2) are used for the production of a low-sulfur fuel oil.

[0297] The following table shows the product yields from the different stages of the process according to example 1.

[0298] [Tables 13] Yields: Percentage by weight of product relative to total feedstock at the given stage to weights Cut a) k) b) i-Sl ) i-S2 ) cS 1) cS 2) j) g) h) e) 0 d) h2, h2s, Cl, CO 3.2 23.4 h2s 3.4 0.2 0.4 0.02 1.0 0.5 nh3 0.5 0.01 0.01 0.02 C1-C2 0.6 8.8 0.1 0.3 0.3 3.1 4.1 LPG 2.6 0.6 36.0 0.1 16.3 16.4 5.9 6.5 2.6 Ethylene 35.9 Propylene 45.6 28.2 Butadiene 2.9 Benzene 18.3 Paraxylene 55.8 Naphtha 15.9 1.4 Cut mainly comprising propylene and ethylene 40.8 C4 cut 48.5 C4-C6 cut 48.1 FCC Gasoline 29.4 Light Naphtha [30-65°C] 19.6 16.8 16.8 Heavy Naphtha [65-175°C] 80.2 67.6 68.9 Selectively Hydrogenated LCN 37.1 Hydrotreated LCN 4.0 Hydrotreated HCN 59.1 C7+ Cut 11.1 Kerosene 6.6 Raffinate 17.8 Reformate 87.2 Diesel 21.4 12.7 LCO 12.2 Atmospheric Residue 53.4 Hydrotreated Atmospheric Residue 82.5 Light Pyrolysis Gasoline 9.1 Heavy Pyrolysis Gasoline 0.6 Oil 0.6 pyrolysis Extract aromatics C6-C10 46.1 Non-aromatic raffinate + aromatics C11+ 53.9 Heavy aromatics C9-C10 1.9 FCC residue (heavy oil) 3.8 Coke 9.6 0.05 Purge (losses) 0.5 0.5 0.1 Total 100.0 101.6 100.0 100.3 100.2 102.4 103.4 100.0 100.0 100.0 100.0 100.4 100.8

[0299] When the total is greater than 100% for a step, this means that a secondary charge has been injected into said step, such as, for example, hydrogen in steps k) and c).

[0300] The following table shows different yields in percentage by weight relative to the weight of the crude oil feedstock entering the process.

[0301] [Tablesl4] Petrochemical Bases 77.2% Olefins 41.5% Ethylene / Propylene Ratio 0.85 Aromatics 35.7% Olefins / Aromatics Ratio 1.16

[0302] Compared to the crude oil feedstock introduced in step a) of atmospheric distillation, the process according to Example 1 makes it possible to achieve total mass yields of 77.2% of basic products for petrochemicals. The olefin yields are: 18.3% ethylene, 21.6% propylene and 1.5% butadiene. The aromatic yields are 8.8% benzene and 26.9% paraxylene. In addition, the sequence specific steps upstream of the steam cracking stage make it possible to limit the formation of coke.

[0303] Example 2: Method according to the embodiment of [Fig.3] with sending of the C4 cut obtained in step d) to step g) as co-load:

[0304] The example below illustrates a particular implementation of the method according to the invention without limiting its scope.

[0305] Example 2 differs from Example 1 by obtaining a C4 cut in steam cracking step d) which is sent as a co-feed to the oligomerization and catalytic cracking step in one step g).

[0306] Thus, in this example, the charge of step g) is composed of cuts 47, 48 and 54. The operating conditions of step g) are unchanged compared to the conditions presented in Table 9 of example 1.

[0307] The following table shows the product yields from the different stages of the process according to example 2.

[0308] [Tables 15] Yields: Percentage by weight of product relative to total feedstock at the given stage to weights Cut a) k) b) i-Sl ) i-S2 ) cS 1) cS 2) j) g) h) e) 0 d) h2, h2s, Cl, CO 3.2 17.4 h2s 3.4 0.2 0.4 0.02 1.0 0.5 nh3 0.5 0.01 0.01 0.02 C1-C2 0.6 8.8 0.1 0.3 0.3 3.1 4.0 LPG 2.6 0.6 36.0 0.1 16.3 16.4 5.9 6.5 2.5 Ethylene 29.4 Propylene 45.6 25.3 Butadiene 2.3 Benzene 18.3 Paraxylene 55.2 Naphtha 15.9 1.4 Cut mainly comprising propylene and ethylene 40.8 C4 cut 48.5 15.6 C4-C6 cut 48.1 FCC Gasoline 29.4 Light Naphtha [30-65°C] 19.6 16.8 16.8 Heavy Naphtha [65-175°C] 80.2 67.6 68.9 Selectively Hydrogenated LCN 37.1 Hydrotreated LCN 4.0 Hydrotreated HCN 59.1 C7+ Cut 11.1 Kerosene 6.6 Raffinate 18.6 Reformate 87.2 Diesel 21.4 12.7 LCO 12.2 Atmospheric Residue 53.4 Hydrotreated Atmospheric Residue 82.5 Light Pyrolysis Gasoline 9.2 Heavy Pyrolysis Gasoline 0.5 Oil 0.5 pyrolysis Extract aromatics C6-C10 46.1 Non-aromatic raffinate + aromatics C11+ 53.9 Heavy aromatics C9-C10 1.8 FCC residue (heavy oil) 3.8 Coke 9.6 0.05 Purge (losses) 0.5 0.5 0.1 Total 100.0 101.6 100.0 100.3 100.2 102.4 103.4 100.0 100.0 100.0 100.0 100.4 100.3

[0309] The following table shows the different yields in percentage by weight relative to the weight of the crude oil feedstock entering the process.

[0310] [Tableauxlô] Petrochemical Bases 78.4% Olefins 41.6% Ethylene / Propylene Ratio 0.79 Aromatics 36.8% Olefins / Aromatics Ratio 1.13

[0311] Compared to the crude oil feedstock introduced in step a) of atmospheric distillation, the process according to Example 2 makes it possible to achieve total mass yields of 78.4% of basic products for petrochemicals. The olefin yields are: 17.7% ethylene, 22.5% propylene and 1.4% butadiene. The aromatic yields are 9.2% benzene and 27.6% paraxylene. The process according to Example 2 makes it possible to significantly increase the conversion of the feedstock into petrochemical products (+1.2%), which is reflected in particular by an increase in the production of propylene (+0.9%) and paraxylene (+0.7%) compared to example 1, and therefore to direct the conversion towards the production of propylene.

Claims

Claims

1. A process for producing olefins and aromatics from a hydrocarbon feedstock comprising crude oil, the process comprising the following steps: (a) an atmospheric distillation step comprising the treatment of all or part of the hydrocarbon feedstock comprising crude oil in an atmospheric distillation unit, and obtaining a naphtha cut, a diesel cut and an atmospheric residue cut; b) a fluid catalytic cracking step comprising the treatment of all or part of the atmospheric residue cut obtained in step a) in an FCC unit comprising a catalytic cracking zone operating in ascending or descending flow containing an FCC catalyst, operating at a temperature at the outlet of the catalytic cracking zone of between 400 and 700°C, at a pressure of the catalytic cracking zone of between 0.1 and 2 MPa, and obtaining an LPG cut, an FCC gasoline cut and a light distillate cut; c) a fixed-bed hydrocracking step comprising the treatment of all or part of a diesel and / or light distillate cut chosen from the cuts obtained in steps a) and b) alone or as a mixture in a hydrocracking unit comprising a reactor containing a hydrocracking catalyst, operated in the presence of hydrogen, at a temperature between 250 and 480°C, under a pressure between 2 and 25 MPa, and obtaining a light naphtha cut and a heavy naphtha cut; d) a steam cracking step comprising the treatment of all or part of the naphtha and / or light naphtha and / or heavy naphtha and / or cuts comprising essentially propylene and ethylene chosen from the cuts obtained in steps a), c) and g) alone or as a mixture in a steam cracking unit comprising a pyrolysis furnace, and obtaining an olefinic cut; e) a catalytic reforming step comprising the treatment of all or part of the heavy naphtha cut obtained in step c) in a catalytic reforming unit comprising a reactor containing a reforming catalyst, operated under a pressure of between 0.1 and 25 MPa and at a temperature of between 480 and 570°C, and obtaining a reformate cut; f) a step of transformation and / or separation of aromatics comprising the treatment of all or part of the reformate cut obtained in step e) in a unit for transformation and / or separation of aromatics, and obtaining an aromatic cut; g) a step of oligomerization and catalytic cracking in one stage, comprising the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained in step b) of fluid catalytic cracking in a unit of oligomerization and catalytic cracking in one stage comprising a reactor containing a catalyst allowing the oligomerization and the catalytic cracking of olefins, operated at a temperature of between 400 and 600°C, and at a pressure of between 0.1 and 1 MPa, and obtaining a cut comprising essentially propylene and ethylene.

2. Process according to claim 1 in which, in step d) of steam cracking, a heavy pyrolysis gasoline cut is also obtained.

3. Process according to any one of the preceding claims, further comprising a step k) of residue hydrotreatment comprising the treatment of all or part of the atmospheric residue cut obtained in step a) in a hydrotreatment unit comprising a reactor containing a hydrotreatment catalyst, operated in the presence of hydrogen, at a temperature between 300°C and 500°C, under a pressure between 5 MPa and 35 MPa, and obtaining a hydrotreated atmospheric residue cut.

4. Process according to claim 3 in which, in step k) of hydrotreatment, a diesel cut is also obtained.

5. Process according to claim 4 in which, the hydrocracking step c) comprises the treatment of all or part of the heavy pyrolysis gasoline cut resulting from the steam cracking step d) and / or a first part of the diesel cut resulting from the atmospheric distillation step a) in a first hydrocracking section c-S1), and the treatment of all or part of the light distillate cut obtained in the fluid catalytic cracking step b) and / or all or part of the diesel cut obtained in the optional residue hydrotreatment step k) and / or a second part of the diesel cut resulting from the atmospheric distillation step a) in a second hydrocracking section c-S2).

6. A process according to any one of the preceding claims, further comprising a step i) of hydrotreating naphtha comprising the treatment of all or part of a naphtha cut and / or FCC gasoline chosen from the cuts obtained in steps a) and b) alone or as a mixture in a hydrotreatment unit comprising a reactor containing a hydrotreatment catalyst, operated in the presence of hydrogen, at a temperature between 200°C and 400°C, under a pressure between 0.2 MPa and 2.5 MPa, preferably between 0.5 MPa and 2.0 MPa, and obtaining a hydrotreated naphtha cut and / or hydrotreated FCC gasoline.

7. Process according to any one of claims 3 to 6 wherein, in step k) of residue hydrotreatment, a naphtha cut is additionally obtained.

8. Process according to claim 7 in which step i) of naphtha hydrotreatment comprises the treatment of all or part of the naphtha cuts resulting from steps a) of atmospheric distillation and k) of residue hydrotreatment in a first hydrotreatment section i-S1), and the treatment of all or part of the FCC gasoline cut obtained in step b) of fluid catalytic cracking in a second hydrotreatment section i-S2).

9. Process according to claim 8 in which the treatment of all or part of the naphtha cuts resulting from steps a) of atmospheric distillation and k) of residue hydrotreatment in the first hydrotreatment section i-Sl) is followed by a step of separation of the hydrotreated naphtha cut to obtain a hydrotreated light naphtha cut and / or a hydrotreated heavy naphtha cut.

10. Process according to claim 8 or 9 wherein the treatment of all or part of the FCC gasoline cut obtained in step b) of fluid catalytic cracking in the hydrotreatment section i-S2) comprises a step of selective hydrogenation of the diolefins into olefins followed by a separation step to obtain a selectively hydrogenated light FCC gasoline cut essentially comprising olefins and a heavy FCC gasoline cut.

11. A process according to any one of the preceding claims, further comprising a step j) of propylene recovery comprising treating all or part of the LPG cut obtained in step b) of fluid catalytic cracking in a propylene recovery unit, and obtaining a C4 cut, a propane cut and a polymer grade propylene cut.

12. A process according to claim 11, wherein step g) of oligomerization and one-step catalytic cracking comprises the treatment of the olefins contained in the LPG and FCC gasoline cuts obtained in step b) of fluid catalytic cracking by sending all or part of the C4 cut obtained in step j) and all or part of the selectively hydrogenated light FCC gasoline cut obtained in step i) into a single-stage oligomerization and catalytic cracking unit.

13. 13. Process according to any one of claims 10 to 12 in which the heavy FCC gasoline cut undergoes a step of hydrogenation of the olefins into paraffins and of removal of sulfur and / or of removal of nitrogen followed by a separation step to obtain a hydrotreated light FCC gasoline cut and / or a hydrotreated heavy FCC gasoline cut.

14. 14. Process according to any one of claims 9 to 13 in which, step d) of steam cracking further comprises the treatment of all or part of the hydrotreated light naphtha cut and / or hydrotreated heavy naphtha and / or hydrotreated light FCC gasoline obtained in step i) of naphtha hydrotreatment.

15. 15. Process according to any one of claims 13 or 14, further comprising a liquid-liquid extraction step h) comprising the treatment of all or part of the hydrotreated heavy FCC gasoline cut obtained in step i) of naphtha hydrotreatment, in a liquid-liquid extraction unit, and obtaining an extract concentrated in aromatic compounds of 6 to 10 carbon atoms and a raffinate concentrated in non-aromatic compounds and in aromatics with 11 carbons and more.

16. 16. Process according to claim 15 in which step e) of catalytic reforming further comprises the treatment of all or part of the raffinate concentrated in non-aromatic compounds and in aromatic compounds with 11 carbons or more obtained in step h) of liquid-liquid extraction.

17. 17. Process according to any one of claims 15 or 16 in which step f) of transformation and / or separation of the aromatics further comprises a treatment of all or part of the extract concentrated in aromatic compounds of 6 to 10 carbon atoms obtained in step h) of liquid-liquid extraction.

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