EP3728519A1

EP3728519A1 - Improved method for converting residues incorporating deep hydroconversion steps and a deasphalting step

Info

Publication number: EP3728519A1
Application number: EP18814905.8A
Authority: EP
Inventors: Joao MARQUES; Matthieu DREILLARD; Frédéric Feugnet; Jean-François Le Coz
Original assignee: IFP Energies Nouvelles IFPEN
Current assignee: IFP Energies Nouvelles IFPEN
Priority date: 2017-12-21
Filing date: 2018-12-07
Publication date: 2020-10-28
Anticipated expiration: 2038-12-07
Also published as: EP3728519B1; US20210102130A1; PL3728519T3; WO2019121074A1; RU2020123947A3; CN111788286A; US11485916B2; RU2020123947A; FR3075810B1; SA520412258B1; FR3075810A1

Abstract

The invention concerns a method for converting heavy hydrocarbon feedstocks of which at least 50% by weight boils at a temperature of at least 300°C, and in particular vacuum residues. The feedstocks are subjected to a first step a) of deep hydroconversion, optionally followed by a step b) of separating a light fraction, and a heavy residual fraction is obtained from step b) of which at least 80% by weight has a boiling temperature of at least 250°C. Said fraction from step b) or the effluent from step a) is then subjected to a second step c) of deep hydroconversion. The overall hourly space velocity for steps a) to c) is less than 0.1 h^-1. The effluent from step c) is fractionated to separate a light fraction. The heavy fraction obtained, of which 80% by weight boils at a temperature of at least 300°C, is sent to a deasphalting step e). The deasphalted fraction DAO is then preferably converted in a step f) chosen from ebullated bed hydroconversion, fluidised bed catalytic cracking and fixed bed hydrocracking.

Description

IMPROVED RESIDUE CONVERSION METHOD INTEGRATING DEEP HYDROCONVERSION STEPS AND A DISASPHALTAGE STEP

The present invention relates to the conversion of heavy hydrocarbon feeds of which at least 50% by weight of a fraction having a boiling point of at least 300 ° C. These are crude oil or feedstocks resulting, directly or after treatment, from the atmospheric and / or vacuum distillation of a crude oil, such as atmospheric or vacuum residues.

The recovery of these oil residues is relatively difficult both from a technical point of view and from an economic point of view. Indeed, new regulatory constraints drastically lower the maximum allowable sulfur content in bunkers (from 3% to 0.5% by weight sulfur). The market is therefore mainly asking for fuels that can be distilled at atmospheric pressure at a temperature below 380 ° C or even 320 ° C.

PRIOR ART

Patent FR 2 906 814 of the applicant describes a process comprising sequentially sequencing a deasphalting step producing a deasphalted oil, a step of hydroconversion of said deasphalted oil to produce an effluent, and a step of distillation of said effluent for produce a residue which is returned with the charge to the deasphalting step. This patent describes a series of processes in which the hydroconversion stage is carried out at conventional space velocities (WH) of 0.1 h ¹ to 5 h ¹ and the SDA stage is carried out upstream of the hydroconversion stage . The high amount of asphalt produced limits the maximum level of overall conversion of the process.

Patent FR-2964386 of the Applicant describes the sequence of a process for treating loads from crude oil, or atmospheric or vacuum distillation of crude oil. The method comprises a boiling bed hydroconversion stage (called the H-Oil® or LC-Fining process) followed by a step of separating a light fraction (boiling point below 300 ° C., preferably less than 300 ° C. 375 ° C), and the resulting heavy fraction is directly subjected to a deasphalting step to produce a deasphalted oil (DAO). DAO can be hydrocracked or hydrotreated or fractionated. The boiling bed hydroconversion stage is carried out at space velocities (WH) of 0.1 h ^{1 to} 10 h ¹ . The example of the patent is carried out at WH = 0.3 h ¹ and at a conversion (by relative to the residue 540 ° C + ie boiling at 540 ° C or higher) around 60% weight on the bubbling bed portion.

This simple and economical process allows a thermal integration within the same reaction section and makes it possible to obtain a DAO of good quality, nevertheless the asphalt yields are high which limits the maximum overall conversion achievable by this process.

It is also known (US-7,938,952) to operate with two-step hydroconversion ebullated bed overall space velocities of at least 0, 1 h ¹ (H-Oil® said process) with an intermediate separation to separate the light fraction and passage of the resulting heavy fraction in the second hydroconversion stage, then the effluent from the second hydroconversion is directly distilled. By "global space velocities" is meant the flow rate of the hydrocarbon feedstock taken under the standard conditions of temperature and pressure divided by all the volumes of the reactors constituting the hydroconversion stages.

Patent FR-3033797 of the Applicant describes a process for treating charges from crude oil, or atmospheric or vacuum distillation of crude oil, at least 80% by weight of which has a boiling point of at least 300 ° C. . The method comprises a hydroconversion step (first hydroconversion), followed by a separation of the light fraction (boiling point below 350 ° C) and the resulting heavy fraction is subjected to a hydroconversion (second hydroconversion) separated from the first, the effluent obtained is then fractionated by distillation. This hydroconversion process is operated at low overall WH, preferably from 0.05 h ¹ to 0.09 h ¹ .

The advantage afforded by the overall low WH is an important purification which makes it possible to obtain a residue with a low content of asphaltenes and Conradson carbon, for a high degree of conversion of the residue (> 75%). The stability of the liquid effluents is improved. The sediment content at the outlet of hydroconversion is reduced, which induces a better operability of the process. The overall conversion of this process is limited by the unconverted heavy effluent.

SUMMARY OF THE INVENTION

It has now been researched a process with improved performance, especially with a high conversion to fuels (naphtha, kerosene, gas oil) to adapt to the market. It was possible to modify the most recent art process (FR-3033797) to increase the conversion of deep hydroconversion steps further lowering the overall WH.

The Applicant has shown that a better solution is to add a deasphalting step to the most recent art process which allows to obtain a high level of the yield and quality of the DAO, and to treat the DAO in at least one conversion step, which preferably operates at high WH, and thus increase the conversion while bringing a significantly improved operability and a substantial saving on the capital invested and a better return on the investment. The present invention also makes it possible to further reduce the amount of asphalt resulting from the higher overall WH processes.

More specifically, the invention relates to a process for converting hydrocarbon feeds of which at least 50%, preferably at least 80% by weight, at a temperature of at least 300 ° C., comprising the following successive stages:

in a step a), a first deep hydroconversion of said hydrocarbon feedstock in the presence of hydrogen is carried out, at an absolute pressure of between 2 MPa and 35 MPa, at a temperature of between 300 ° C. and 550 ° C., with a quantity of hydrogen ranging from 50 Nm ³ / m ^{3 to} 5000 Nm ³ / m ³ , with a catalyst containing at least one Group VIII metal selected from nickel and cobalt and at least one Group VIB metal selected from molybdenum and tungsten, optionally a step b) of separating a light fraction from a part or all of the effluent resulting from said first hydroconversion, and at least one heavy fraction is obtained, at least 80% of which weight has a boiling point of at least 250 ° C,

in a step c), a second deep hydroconversion of part or all of the liquid effluent resulting from step a) or the heavy fraction resulting from step b) is carried out in the presence of hydrogen, at an absolute pressure of between 2 MPa and 35 MPa, at a temperature between 300 ° C. and 550 ° C., with a quantity of hydrogen of between 50 Nm ³ / m ³ and 5000 Nm ³ / m ³ , with a catalyst containing at least one Group VIII metal selected from nickel and cobalt and at least one Group VIB metal selected from molybdenum and tungsten,

and the overall hourly space velocity for steps a) to c) is less than 0.1 h ¹ , the overall speed being the liquid feed rate of hydroconversion step a) taken under standard temperature conditions and pressure, relative to the total volume of the reactors of steps a) and c), a step d) of separating part or all of the effluent resulting from said second hydroconversion into at least one light fraction and at least one heavy fraction of which at least 80% by weight has a boiling point of at least 300 ° C,

a step e) of deasphalting said heavy fraction resulting from step d), at a temperature of between 60 ° C. and 250 ° C. with at least one hydrocarbon solvent having from 3 to 7 carbon atoms, and a solvent ratio / charge (volume / volume) of between 4/1 and 9/1, and a deasphalted DAO fraction and an asphalt are obtained.

Advantageously, the process comprises a step f) of converting part or all of said optionally distilled DAO fraction.

Preferably, the DAO is distilled before the conversion step f) so as to separate a heavy fraction of which at least 80% by weight has a boiling point of at least 375 ° C., or at least 400 ° C. , or at least 450 ° C or at least 500 ° C, and preferably at least 540 ° C, and said heavy fraction sent in part or in full in the conversion step f).

Preferably, a part or all of the DAO fraction is sent, preferably directly, in a conversion step operating with a process selected from the group consisting of fixed bed hydrocracking, fluidized catalytic cracking, and the like. hydroconversion in a bubbling bed, these processes possibly comprising prior hydrotreatment.

According to a preferred embodiment, part or all of the DAO deasphalted fraction is subjected to fixed bed hydrocracking, in the presence of hydrogen, at an absolute pressure of between 5 MPa and 35 MPa, at a temperature advantageously comprised between 300 and 500 ° C, a WH of between 0.1 h ¹ and 5h ¹ , and a quantity of hydrogen of between 100 Nm ³ / m ³ and 1000 Nm ³ / m ³ (normal cubic meters (Nm ³ ) per meter cube (m ³ ) of liquid charge), and in the presence of a catalyst containing at least one element of the non-noble group VIII and at least one element of the group VIB and comprising a support containing at least one zeolite.

According to another preferred embodiment, part or all of the DAO deasphalted fraction is subjected to FCC fluidized catalytic cracking in the presence of a catalyst, preferably free of metals, comprising alumina, silica, silica-alumina, and preferably comprising at least one zeolite.

According to another preferred embodiment, part or all of the DAO deasphalted fraction is subjected to bubbling bed hydroconversion, carried out in the presence of hydrogen, under an absolute pressure of between 2 MPa and 35 MPa, at a temperature between

300 ° C and 550 ° C, a quantity of hydrogen of between 50 Nm ³ / m ³ and 5000 Nm ³ / m ³

(normal cubic meters (Nm ³ ) per cubic meter (m ³ ) of liquid load), including WH

-1 -1

between 0.1 h and 10 h and in the presence of a catalyst containing a support and at least one Group VIII metal selected from nickel and cobalt and at least one Group VIB metal selected from molybdenum and tungsten.

It is possible that at least a portion of said DAO deasphalted fraction is recycled to step a) and / or step c).

Advantageously, in the separation step d), the effluent resulting from said second hydroconversion is separated into at least one light fraction and at least one heavy fraction of which at least 80% by weight has a boiling point of at least 375. ° C, or at least 400 ° C, or at least 450 ° C or at least 500 ° C, and preferably at least 540 ° C.

Generally, steps a) and c) are carried out under an absolute pressure of between 5 MPa and 25 MPa and preferably between 6 MPa and 20 MPa at a temperature of between 350 ° C. and 500 ° C. and preferred manner between 370 ° C and 430 ° C, and more preferably between 380 ° C and 430 ° C, with a quantity of hydrogen of between 100 Nm ³ / m ³ and 2000 Nm ³ / m ³ and very preferably between 200 Nm ³ / m ³ and 1000 Nm ³ / m ³ , the hourly space velocity (WH) being at least 0.05 h ¹ , preferably between 0.05 h ¹ and 0, 09: ^1,

Generally, step e) is carried out with a solvent selected from the group consisting of butane, pentane or hexane, as well as mixtures thereof.

DETAILED DESCRIPTION OF THE INVENTION

The charges

The fillers that are treated in the context of the present invention are those of which at least 50%, preferably at least 80% by weight has a boiling point of at least 300 ° C (T20 = 300 ° C), preferably at least 350 ° C or at least 375 ° C.

These are crude oils or heavy hydrocarbon fractions derived from the atmospheric distillation and / or vacuum of a crude oil. It can also be residues atmospheric and / or vacuum residues, and in particular atmospheric and / or vacuum residues resulting from hydrotreatment, hydrocracking and / or hydroconversion. It can also be vacuum distillates, cuts from a catalytic cracking unit such as FCC (Fluidized Catalytic Cracking), a coking unit or visbreaking.

Preferably, they are vacuum residues. Generally these residues are fractions of which at least 80 wt% at boiling temperature of at least 450 ° C or higher, and most often at least 500 ° C or 540 ° C.

Also suitable as fillers are aromatic cuts extracted from a lubricant production unit, deasphalted oils (raffinais from a deasphalting unit), asphalts (residues from a deasphalting unit).

The feed may also be a residual fraction resulting from the direct liquefaction of coal (an atmospheric residue and / or a vacuum residue resulting, for example, from the H-Coal® process), a vacuum distillate resulting from the direct liquefaction of coal (by example of the H-Coal® process), coal pyrolysis residues or shale oils, or a residual fraction resulting from the direct liquefaction of the lignocellulosic biomass alone or mixed with coal and / or a petroleum fraction.

All these fillers can be used alone or mixed.

The feeds mentioned above contain impurities, such as metals, sulfur, nitrogen, Conradson carbon and insolubles with heptane, also called C ₇ asphaltenes. The metal contents are generally greater than 20 ppm by weight, most often greater than 100 ppm by weight. The sulfur content is greater than 0.1%, often greater than 1% by weight or 2% by weight. The level of C ₇ -asphaltenes (asphaltenes insoluble in heptane according to the standard NFT60-115) amounts to at least 0.1% by weight and is often greater than 3% by weight. The Conradson carbon content is at least 3%, often at least 5% by weight. The Conradson carbon content is defined by ASTM D 482 and represents for the skilled person a well-known evaluation of the amount of carbon residue produced after pyrolysis under standard conditions of temperature and pressure. These contents are expressed as% by weight relative to the total weight of the filler.

The first stage of deep hydroconversion (step

The feed is treated in a hydroconversion stage a) comprising at least one or more three-phase reactors arranged in series and / or in parallel. These reactors hydroconversion can, inter alia, be fixed-bed type reactors, moving bed, bubbling bed, and / or hybrid bed, depending on the load to be treated. In the present application, the term "hybrid bed" refers to a mixed bed of catalysts of very different particle size, simultaneously comprising at least one catalyst which is maintained in the reactor (typical operation of a bubbling bed) and at least one entrained catalyst. ("Slurry" according to the English terminology) which enters the reactor with the load and which is driven out of the reactor with the effluents (typical operation of a driven bed).

The invention is particularly suitable for bubbling bed reactors. Thus, this step is advantageously carried out using the technology and under the conditions of the H-Oil® process as described, for example, in US Pat. No. 4,521,295 or US Pat. No. 4,494,060 or US Pat. Aiche, March 19-23, 1995, Houston, Texas, paper number 46d, "Second generation ebullated bed technology". Each reactor advantageously comprises a recirculation pump for maintaining the catalyst in a bubbling bed by continuous recycling of at least a portion of liquid fraction advantageously withdrawn at the top of the reactor and reinjected at the bottom of the reactor.

In this step a), said charge is converted under specific hydroconversion conditions. Step a) is carried out under an absolute pressure of between 2 MPa and 35 MPa, preferably between 5 MPa and 25 MPa and, preferably, between 6 MPa and 20 MPa, at a temperature of between 300 ° C. and 550 ° C. and preferably between 350 ° C and 500 ° C and preferably between 370 ° C and 430 ° C, and more preferably between 380 ° C and 430 ° C. The quantity of hydrogen, advantageously mixed with the feedstock, is preferably between 50 Nm ³ / m ³ and 5000 Nm ³ / m ³ of liquid feed taken under standard conditions of temperature and pressure, preferably between 100 Nm ³ / m ³ and 2000 Nm ³ / m ³ and very preferably between 200 Nm ³ / m ³ and 1000 Nm ³ / m ³ .

The hydroconversion catalyst used in step a) contains one or more elements from groups 4 to 12 of the periodic table of the elements, which are deposited on a support. It is advantageous to use a catalyst comprising a support, preferably amorphous, such as silica, alumina, silica-alumina, titanium dioxide or combinations of these structures, and very preferably alumina. The catalyst contains at least one non-noble group VIII metal selected from nickel and cobalt and preferably nickel, and at least one group VIB metal selected from molybdenum and tungsten and preferably the group VIB metal is molybdenum.

Advantageously, the hydroconversion catalyst of step a) is a catalyst comprising an alumina support and at least one Group VIII metal chosen from nickel and cobalt, preferably nickel, and at least one selected Group VIB metal. preferably molybdenum and tungsten, the Group VIB metal is molybdenum. Preferably, the hydroconversion catalyst comprises nickel and molybdenum.

Generally, the metal content of the non-noble group VIII (in particular nickel) is advantageously between 0.5% to 10% expressed by weight of metal oxide (in particular NiO) and preferably between 1% to 6% by weight. % weight, and the metal content of group VIB (in particular molybdenum) is advantageously between 1% and 30% expressed by weight of metal oxide (in particular MoO ₃ ) and preferably between 4% and 20% by weight .

This catalyst is advantageously used in the form of extrudates or beads.

The balls have for example a diameter of between 0.4 mm and 4.0 mm

The extrudates, for example, have a cylindrical shape with a diameter of between 0.5 mm and

4.0 mm and a length of between 1 mm and 5 mm. Extrusions can also be objects of a different shape such as trilobes, regular or irregular tetralobes, or other multilobes. Catalysts of other forms can also be used.

The size of these different forms of catalysts can be characterized using the equivalent diameter. The equivalent diameter is defined as 6 times the ratio between the volume of the particle and the external surface of the particle. The catalyst used in the form of extrusions, beads or other forms therefore has an equivalent diameter of between 0.4 mm and 4.4 mm.

These catalysts are well known to those skilled in the art. The metal contents are expressed relative to the total weight of the catalyst.

In one of the embodiments according to the invention, the deep hydroconversion step a) is carried out in a hybrid bed, comprising simultaneously at least one catalyst which is maintained in the reactor and at least one entrained catalyst which enters the reactor with the charge and which is driven out of the reactor with the effluents. In this case, the entrained catalyst, also called slurry catalyst, is used in addition to the catalyst maintained in the bubbling bed reactor in the process according to the invention. Said catalyst As a difference with the catalyst maintained in the reactor has a particle size and a density adapted to its drive. The term "catalyst entrainment" is understood to mean its circulation in the three-phase reactor (s) by the liquid streams, said catalyst circulating from bottom to top, with the feedstock, in the said three-phase reactor (s), and being drawn off. said one or more three-phase reactors with the liquid effluent produced. Because of its small size, which can vary from a few nanometers to a hundred micrometers (typically from 0.001 pm to 100 pm), the entrained catalyst is very well dispersed in the charge to be converted, thus greatly improving the reactions of hydrogenation and hydroconversion in the entire reactor, reducing coke formation and increasing the conversion of the heavy fraction of the feedstock. These entrained catalysts are well known to those skilled in the art.

The entrained catalyst can be formed and activated ex situ, outside the reactor under conditions suitable for activation, and then injected with the feedstock. The entrained catalyst can also be formed and activated in situ under the reaction conditions of one of the hydroconversion stages.

The entrained catalyst, or its precursor, is injected with the feed to be converted at the reactor inlet. The catalyst passes through the reactor with the feeds and products being converted, and then is entrained with the reaction products out of the reactor. The entrained catalysts exist either in the form of a powder (US Pat. No. 4,303,634), which is the case of the supported supported catalysts described below, or in the form of a so-called soluble catalyst (US Pat. No. 5,288,681). In the reactor, the entrained catalyst is in the form of dispersed solid particles, colloids or molecular species dissolved in the feed, depending on the nature of the catalyst. Such precursors and entrained catalysts which can be used in the process according to the invention are widely described in the literature.

The entrained catalysts used may be heterogeneous solid powders (such as natural ores, iron sulphate, etc.), dispersed catalysts derived from water-soluble precursors, such as phosphomolybdic acid, molybdate, and the like. ammonium, or a mixture of Mo or Ni oxide with aqueous ammonia, or from precursors soluble in an organic phase. In a preferred manner, the driven catalysts used are derived from precursors that are soluble in an organic phase. The precursors soluble in an organic phase are preferably chosen from the group of organometallic compounds consisting of the naphthenates of Mo, Co, Fe, or Ni, or the multi-carbonyl compounds of these metals, for example 2-ethyl hexanoates. Mo or Ni, acetylacetonates of Mo or Ni, C7-C12 fatty acid salts of Mo or W, etc. Preferably the precursor is The entrained catalysts can be used in the presence of a surfactant to improve the dispersion of the metals, especially when the catalyst is bimetallic.

According to one embodiment, so-called oil-soluble entrained catalysts are used, and the precursor is mixed with a carbonaceous feedstock (which may be a part of the feed to be processed, an external feedstock, etc.), the mixture is optionally dried at least in part, then or simultaneously is sulphurized by addition of a sulfur compound and heated. The preparations of these entrained catalysts are described in the prior art.

Additives may be added during the preparation of the entrained catalyst or the entrained catalyst before it is injected into the reactor. These are for example a gas oil, an aromatic additive, solid particles whose size is preferably less than 1 mm, etc. The preferred additives are inorganic oxides such as alumina, silica, mixed Al / Si oxides, supported spent catalysts (for example, on alumina and / or silica) containing at least one group VIII element (such as Ni, Co) and / or at least one group VI B element (such as Mo, W). Examples of catalysts described in US Patent 2008/177124. Coke, optionally pretreated, may also be used. These additives are widely described in the literature. The entrained catalyst can advantageously be obtained by injecting at least one active phase precursor directly into the hydroconversion reactor (s) and / or into the feedstock prior to the introduction of said feedstock into the hydroconversion stage (s). The addition of precursor may be introduced continuously or discontinuously (depending on the operation, the type of charges processed, product specifications sought and operability). According to one or more embodiments, the entrained catalyst precursor (s) are premixed with a hydrocarbon oil composed for example of hydrocarbons of which at least 50% by weight relative to the total weight of the catalyst. hydrocarbon oil have a boiling point between 180 ° C and 540 ° C to form a diluted precursor premix. According to one or more embodiments, the precursor or premix of diluted precursor is dispersed in the heavy hydrocarbon feedstock, for example by dynamic mixing (for example using a rotor, a stirrer, etc.). ), by static mixing (for example by means of an injector, by gavage, via a static mixer, etc.), or only added to the charge to obtain a mixture. Any mixing and stirring techniques known to those skilled in the art can be used to disperse the precursor or diluted precursor mixture into the feed of one or more hydroconversion steps. The at least one active phase precursor (s) of the unsupported catalyst may or may be in liquid form, such as, for example, precursors of metals soluble in organic media, for example molybdenum octoates and / or molybdenum naphthenates, or water-soluble compounds, such as, for example, phosphomolybdic acids and / or ammonium heptamolybdates, among others.

Said entrained catalyst can be formed and activated ex situ outside the reactor under conditions suitable for activation and then injected with the feedstock. Said entrained catalyst can also be formed and activated in situ under the reaction conditions of one of the hydroconversion stages.

According to one embodiment, said driven catalyst may be supported, that is to say comprise a support for the active phase. In this case, the supported catalyst can advantageously be obtained:

- by grinding the supported hydroconversion catalyst, fresh or spent or by grinding a mixture of fresh and spent catalysts, or

- Impregnation of at least one active phase precursor on a support having a particle size suitable for its drive and preferably a size between 0.001 pm and 100 pm.

Said supported supported catalyst preferably comprises a support, such as silica, alumina, silica-alumina, titanium dioxide, clays, carbon, coal, coke, carbon black, lignite, or combinations of these structures, and very preferably alumina.

The active phase of said supported supported catalyst contains one or more elements of groups 4 to 12 of the periodic table of the elements, which may be deposited on a support or not. The active phase of said entrained catalyst advantageously contains at least one Group VIB metal selected from molybdenum and tungsten, and preferably the Group VIB metal is molybdenum. Said group VIB metal may be in combination with at least one non-noble group VIII metal selected from nickel, cobalt, iron, ruthenium and preferably nickel.

In the present description, groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, editor CRC press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, Group VIII metals according to the CAS classification correspond to the metals of columns 8, 9 and 10 according to the new classification IU PAC. In the case of supported supported catalysts, the non-noble group VIII metal content, in particular nickel, is advantageously between 0.5% to 10% by weight of metal oxide (in particular NiO), and preferably between 1% to 6% by weight. The content of Group VI B metal, in particular molybdenum, is advantageously between 1% and 30% expressed by weight of metal oxide (in particular molybdenum trioxide MoO ₃ ), and preferably between 4% and 20% by weight. % weight The metal contents are expressed as a weight percent of metal oxide with respect to the weight of the supported supported catalyst.

Advantageously, the supported driven catalyst may additionally contain at least one doping element chosen from phosphorus, boron and halogens (group VI IA or group 17 of the new notation of the periodic table of the elements), preferably phosphorus. .

In one of the implementations of the process according to the invention, and in particular in a bubbling bed reactor, each reactor of the hydroconversion stage a) can use a different catalyst adapted to the feed that is sent to this reactor.

In one of the implementations of the process according to the invention, several different types of catalyst can be used in each reactor.

In a preferred implementation, each reactor of step a) may contain one or more catalysts suitable for bubbling bed operation, and optionally one or more additional entrained catalysts.

According to the common technology (described in the prior art, for example FR 3033797), the used hydroconversion catalyst may be partly replaced by fresh catalyst by racking, the latter being withdrawn preferably at the bottom of the reactor, and the catalyst fresh being introduced into the reactor. The fresh catalyst may be replaced in whole or in part by spent catalyst and / or regenerated catalyst (without coke) and / or rejuvenated catalyst (regenerated catalyst with added catalyst activity enhancing compound) and / or catalyst reactivated via the extraction of poisons and inhibitors such as the deposited metals resulting from the hydrodemetallation reactions and elimination of the formed coke.

Bl step separation - optional

The process preferably operates with step b). At least a portion, and preferably all, of the effluent from hydroconversion step a) may undergo one or more separation steps.

This separation step is carried out with the objective of separating from the effluent at least one light fraction (so-called first light fraction) and thus obtaining at least one heavy liquid fraction of which at least 80% by weight has a boiling point of at least 250 ° C, and preferably at least 300 ° C.

The light fraction may then be sent at least partly to a fractionation section where it is then advantageously separated from the light gases (H ₂ and C ₁ -C ₄ ), for example by passing through a flash balloon. The hydrogen gas is recovered and is then advantageously recycled at the inlet of the deep hydroconversion stage a) or sent to the deep hydroconversion stage c) and / or to other units of the refinery. The light liquid fraction separated from the light gases can then be advantageously sent to fractionation step d). This light liquid fraction thus separated contains dissolved light gases, naphtha (fraction boiling at a temperature below 150 ° C), kerosene (fraction boiling between 150 ° C and 250 ° C) and at least a portion of the boiling gas oil between 250 ° C and 375 ° C.

The heavy liquid fraction from step b) contains the compounds boiling at 250 ° C., preferably at 300 ° C. or more, and in particular those boiling at 375 ° C. and up to less than 540 ° C. (distillate). under vacuum) and those boiling at a temperature of 540 ° C and higher which correspond to the vacuum residue (which is the unconverted fraction). It can therefore contain a portion of the gas oil fraction, that is to say compounds boiling between 250 ° C and 375 ° C. This heavy liquid fraction is sent in whole or in part to the hydroconversion stage c).

The separation step may be implemented by any separation means known to those skilled in the art. Preferably, the separation step b) is carried out by one or more flash balloons in series, and preferably by a single flash ball. Preferably, the flash balloon is operated at a pressure and a temperature close to the operating conditions of the last reactor of the hydroconversion stage a).

In another implementation, the separation step is performed by a sequence of several flash balloons, operating at operating conditions different from those of the last reactor of the hydroconversion stage a) and making it possible to obtain several fractions. light liquids. These may then be sent in whole or in part to a splitting section.

In another implementation, the separation step is performed by one or more stripping columns (drive) with steam and / or hydrogen. By this means, the effluent from hydroconversion step a) will be separated into a light fraction and a heavy liquid fraction.

In another implementation, the separation step is carried out by an atmospheric distillation column alone or followed by a vacuum distillation column.

The separation step can also be a combination of these different implementations.

Optionally, before being sent to the hydroconversion step c) according to the invention, the heavy liquid fraction may be subjected to a separation step of compounds with a boiling point of 540 ° C or less. At least 80% by weight of the heavy fraction that is obtained has a boiling point of at least 540 ° C. This separation can be performed by stripping with steam and / or hydrogen, using one or more stripping columns.

The second deep hydroconversion (step c)

The liquid effluent from step a) or the heavy fraction from separation step b) is subjected to deep hydroconversion in step c). There may or may not be recycling of said effluent or fractions to step a). Steps a) and c) are different steps performed in separate areas.

The operating condition intervals, catalysts, implemented are those described for step a).

The operating conditions of step c) are identical to or different from those of step a).

According to the invention, the global hourly space velocity (WH), that is to say the liquid feed rate of the hydroconversion stage a) taken under standard conditions of temperature and pressure, based on the volume total of the reactors of steps a) and c), is less than 0.1 h ¹ , generally at least 0.05 h ¹ , preferably between 0.05 h ¹ and 0.09 h ¹ . Step cO splitting

The effluent from the hydroconversion stage c) is then subjected, in whole or in part, to a fractionation stage d). This fractionation can be achieved by one or more flash balloons in series, preferably by a sequence of at least two successive flash balloons, preferably by one or more stripping columns with steam and / or hydrogen. , more preferably by an atmospheric distillation column, more preferably by an atmospheric distillation column and a vacuum column on the atmospheric residue, even more preferably by one or more flash flasks, an atmospheric distillation column and a vacuum column on the atmospheric residue. This fractionation can also be achieved by a combination of the different separation means described above.

The fractionation step is carried out with the objective of separating the light gases and the recoverable distillates (gasoline, gas oil) and so as to obtain at least one heavy liquid fraction of which at least 80% by weight is at least 300 ° C. or at least 350 ° C, preferably at least 375 ° C, or at least 400 ° C, or at least 450 ° C or at least 500 ° C and most preferably a residue fraction of which 80% is obtained weight at least 540 ° C or more. Preferably, a residue is removed under vacuum (by atmospheric distillation and then vacuum distillation of the atmospheric residue) having an initial boiling point of 540 ° C.

Step e) deasphalting

Said heavy liquid fraction obtained in step d), and in said residue fraction, then undergoes according to the process according to the invention a step d) deasphalting, to obtain a deasphalted hydrocarbon fraction called DAO and asphalt.

The deasphalting is generally carried out at a temperature between 60 ° C and 250 ° C with at least one hydrocarbon solvent having 3 to 7 carbon atoms, preferably the solvent is butane, pentane or hexane, as well as mixtures thereof, optionally with at least one additive added. The solvent / charge ratios (volume / volume) at deasphalting are generally between 4/1 and 9/1, often between 4/1 and 8/1.

Useful solvents and additives are widely described. It is also possible and advantageous to carry out the recovery of the solvent according to the opticritic process, that is to say using a solvent under supercritical conditions in the separation section. This process makes it possible in particular to significantly improve the overall economy of the process. This Deasphalting can be done in one or more mixer-settlers or in one or more extraction columns.

It is possible to use a technique using at least one extraction column and preferably only one (eg the Solvahl ™ process).

The deasphalting unit produces a deasphalted hydrocarbon cut DAO (also called deasphalted oil or deasphalting raffinate) substantially free of C ₇ asphaltenes and a residual asphalt concentrating most of the impurities of the residue and which is withdrawn.

The yield of DAO is generally between 40% and 90% by weight depending on the quality of the heavy liquid fraction sent, the operating conditions and the solvent used.

The following table gives the ranges of the typical operating conditions for deasphalting according to the solvent:

The deasphalting conditions are adapted to the quality of the DAO to be obtained and to the incoming deasphalting charge.

These conditions allow a substantial lowering of the Conradson carbon content and the C ₇ asphaltene content. The deasphalted hydrocarbon fraction DAO obtained advantageously has a C ₇ asphaltene content of less than 0.5% by weight, preferably less than 0.1% by weight, and better still less than 0.08% or 0.07% by weight, relative to total weight of said cut.

In one embodiment, all or preferably a portion of said DAO deasphalted fraction is recycled to step a) and / or step c).

Conversion of the DAO fraction (step f)

The DAO fraction may be sent in whole or in part in an additional conversion step f). Preferably, the DAO is sent directly to the conversion step. Preferably, the whole of the DAO fraction is sent directly to the step of conversion, that is to say that it undergoes no treatment except possibly one or more fractionation steps.

This step makes it possible to bring the conversion of the process to a very high level (compared to the 540 ° C + cut), and more often more than 90%. The targeted conversion processes in this step are fixed bed hydrocracking, fluidized catalytic cracking FCC, boiling bed hydroconversion (H-Oil DC), these conversion processes may be preceded by hydrotreatment.

If necessary, said deasphalted hydrocarbon fraction DAO may be subjected to atmospheric distillation, optionally followed by vacuum distillation, in particular when step c) does not involve distillation.

The cuts of recoverable products obtained are the essence cut (150 ° C), one or more medium distillate cuts (150-375 ° C) and one or more heavier fraction (s). boiling 375 ° C or more.

This heavier fraction (s) is preferably sent to the conversion step f).

The characteristics of this fraction are particularly interesting (low Conradson carbon, low C7 asphaltene content, low S contents, metals).

In one embodiment, the deasphalted hydrocarbon fraction DAO is advantageously distilled in admixture with at least a portion, and preferably all, of the light liquid fraction from step b.

In another embodiment, said mixture can be sent to the conversion step f) without prior fractionation (distillation).

For the distillation, the DAO may also have been mixed with a feedstock external to the process, such as, for example, distillate slices under vacuum, atmospheric residue or vacuum residue resulting from the primary (crude) fractionation of the refinery.

The process preferably operates without distillation. The fraction DAO, in part or in whole, is then sent as in step f).

The conversion step may be fixed bed hydrocracking. It can advantageously take place in one or more reactors or in a single reactor comprising one or more catalytic beds.

Fixed bed hydrocracking implements acid catalysis in the presence of hydrogen. The presence of nitrogen and other impurities in said mixture requires prior pretreatment to avoid deactivation of the catalyst. For this purpose, at least one fixed bed of hydrotreatment catalyst followed by at least one fixed bed of a hydrocracking catalyst is generally used. These catalysts are well known to those skilled in the art. It is preferable to employ one of the catalysts described by the applicant in EP-B-1 13297 and EP-B-1 13284.

The catalysts contain at least one non-noble group VIII element (Ni and / or Co) and at least one group VI B element (Mo and / or W). The content of group VIII elements is advantageously between 1% and 10% by weight of oxides relative to the total catalyst mass, preferably between 1.5% and 9% by weight and very preferably between 2% and 8% by weight. % weight The contents of group VI B elements are advantageously between 5% and 40% by weight of oxides relative to the total mass of the catalyst, preferably between 8% and 37% by weight and very preferably between 10% and 35%. weight. The contents are expressed relative to the total weight of the catalyst.

The support of the hydrotreatment catalysts is generally alumina; that of the hydrocracking catalysts contains one or more zeolites (zeolites Y or b most often) generally mixed with alumina and / or silica-alumina. The weight contents of zeolite are generally less than 80% by weight.

The hydrotreatment and hydrocracking catalysts may also contain at least one organic additive.

It is preferably carried out under an absolute pressure of between 5 MPa and 35 MPa and preferably between 10 MPa and 20 MPa, at a temperature advantageously between 300 ° C. and 500 ° C. and preferably between 350 ° C. and 450 ° C. . The WH and the hydrogen partial pressure are selected according to the characteristics of the batch to be treated and the desired conversion. Preferably, the WH is between 0.1 h ¹ and 5 h ¹ and preferably between 0.15 h ¹ and 2 h ¹ . The quantity of hydrogen, advantageously mixed with the feedstock, is preferably between 100 Nm ³ / m ³ and 1000 Nm ³ / m ³ of liquid feed and preferably between 500 Nm ³ / m ³ and 3000 Nm ³ / m ³ .

The boiling-bed hydroconversion stage treating the DAO fraction (H-Oil® DC) can advantageously be carried out under an absolute pressure of between 2 MPa and 35 MPa, preferably between 5 MPa and 25 MPa, and preferably between 6 MPa and 20 MPa, at a temperature between 300 ° C and 550 ° C and preferably between 350 ° C and 500 ° C and in a preferred manner between 380 ° C and 470 ° C, and more preferably between 400 ° C and 450 ° C. The quantity of hydrogen, advantageously mixed with the feedstock, is preferably between 50 Nm ³ / m ³ and 5000 Nm ³ / m ³ of liquid feed taken under standard conditions of temperature and pressure, preferably between 100 Nm ³ / m ³ and 2000 Nm ³ / m ³ and very preferably between 200 Nm ³ / m ³ and 1000 Nm ³ / m ³ .

Preferably, the WH of this step is between 0.1 h -1 and 10 h -1 and so

-1 -1

preferred between 0, 15 h and 5 h.

The hydroconversion catalyst used in a bubbling bed contains one or more elements from groups 4 to 12 of the periodic table of the elements, which are deposited on a support. It is advantageous to use a catalyst comprising a support, preferably amorphous, such as silica, alumina, silica-alumina, titanium dioxide or combinations of these structures, and very preferably alumina. The catalyst contains at least one Group VIII metal selected from nickel and cobalt and preferably nickel, and at least one Group VIB metal selected from molybdenum and tungsten and preferably the Group VIB metal is molybdenum .

Advantageously, the hydroconversion catalyst is a catalyst comprising an alumina support and at least one Group VIII metal chosen from nickel and cobalt, preferably nickel, and at least one Group VIB metal chosen from molybdenum and tungsten. preferably, the Group VIB metal is molybdenum. Preferably, the hydroconversion catalyst comprises nickel and molybdenum.

The nickel content is advantageously between 0.5% by weight and 10% by weight, expressed by weight of nickel oxide (NiO) and preferably between 1% by weight and 6% by weight, and the molybdenum content is advantageously between 1% by weight. % by weight and 30% by weight expressed by weight of molybdenum trioxide (MoO ₃ ) and preferably between 4% and 20% by weight. The contents are expressed relative to the total weight of the catalyst.

This catalyst is advantageously used in the form of extrudates or beads. The extrudates have for example a diameter of between 0.5 mm and 2.0 mm and a length of between 1 mm and 5 mm. These catalysts are well known to those skilled in the art.

According to the common technology (described in the prior art, for example FR-3033797), the used hydroconversion catalyst may be partly replaced by fresh catalyst by withdrawal, the latter being withdrawn preferably at the bottom of the reactor, and the fresh catalyst being introduced into the reactor. The fresh catalyst can be replaced in whole or in part by spent catalyst and / or regenerated catalyst (without coke) and / or rejuvenated catalyst (regenerated catalyst supplemented with a compound increasing the activity of the catalyst) and / or reactivated catalyst via the extraction of poisons and inhibitors as the deposited metals resulting from the hydrodemetallation reactions and elimination of the coke formed.

The effluent from the conversion stage f) is then generally distilled so as to recover the recoverable gasoline and gasoil cuts. The residual unconverted fraction can be recycled at one of the process steps.

In another embodiment, the conversion step f) can be carried out through a fluidized catalytic cracking unit. DAO can be processed in coprocessing with one or more heavy loads of VGO, HDT VGO, residue type or alone.

The fluidized catalytic cracking unit can comprise a single reactor treating both the heavy load and the DAO or only the DAO, or two separate reactors treating one the heavy load, the other the DAO. In addition, each of the reactors may be upflow or downflow. Most often, both reactors will have the same flow mode.

When the catalytic cracking is carried out in coprocessing of one or more heavy loads and a DAO:

1) in a single upflow reactor, the reactor outlet temperature (ROT) is between 450 ° C and 650 ° C, preferably between 470 ° C and 620 ° C, and the C / O ratio is between 2 and 20 and preferably between 4 and 15.

2) in a single reactor is downflow, the reactor outlet temperature (ROT) is between 480 ° C and 650 ° C, and the C / O ratio is between 10 and 50.

3) in two separate upflow reactors, the first reactor carrying out the cracking of the heavy charge (s) operates at a reactor outlet temperature (ROT1) of between 450 ° C. and 650 ° C., preferably between 470 ° C. and 620 ° C, and a C / O ratio of between 2 and 20, preferably between 4 and 15. The second reactor performing the cracking of the DAO operates at a reactor outlet temperature (ROT2) of between 500 ° C. and 600 ° C. , preferably between 520 ° C and 580 ° C, with a C / O ratio of between 2 and 20.

4) in two separate downflow FCC reactors, the first FCC reactor cracking the heavy load (s) operates at a reactor outlet temperature (ROT1) of between 480 ° C and 650 ° C with an included C / O ratio between 10 and 50. The second FCC reactor cracking the DAO operates at a reactor outlet temperature (ROT2) between 570 ° C and 600 ° C, with a C / O ratio of between 10 and 50.

When catalytic cracking is performed on DAO alone:

1) in an upflow reactor, the reactor operates at a reactor outlet temperature (ROT) of between 500 ° C. and 600 ° C., preferably between 520 ° C. and 580 ° C., with a C / O ratio of between 2 and 20.

2) in a downflow reactor, the reactor operates at a reactor outlet temperature (ROT2) between 570 ° C and 600 ° C, with a C / O ratio of between 10 and 50.

The spent catalyst streams from the two FCC reactors are separated from the cracking effluents by any solid gas separation system known to those skilled in the art and regenerated in a common regeneration zone.

The effluent from the catalytic cracking reactor (or the two effluents if there are two reactors) is sent to a fractionation zone. This separation unit usually comprises a primary separation of effluents allowing, among other things, the production of salvageable cuts such as gasoline, middle distillate and heavy distillate cuts. The residual unconverted fraction can be recycled at one of the process steps.

The catalyst of the catalytic cracking stage in a fluidized bed is typically composed of particles of average diameter generally between 40 micrometers and 140 micrometers, and most often between 50 micrometers and 120 micrometers.

The catalytic cracking catalyst contains at least one suitable matrix such as alumina, silica or silica-alumina with or without the presence of a Y-type zeolite dispersed in this matrix. The catalyst may further comprise at least one zeolite having a shape selectivity of one of the following structural types: MEL (for example ZSM-1 1), MFI (for example ZSM-5), NES, EUO, FER, CHA (eg SAPO-34), MFS, MWW. It may also comprise one of the following zeolites: NU-85, NU-86, NU-88 and IM-5, which also have a shape selectivity.

The advantage of these zeolites having a shape selectivity is to obtain a better selectivity propylene / isobutene, ie a higher propylene / isobutene ratio in the cracking effluents.

The proportion of zeolite having a shape selectivity with respect to the total amount of zeolite may vary depending on the charges used and the structure of the desired products. Often, from 0.1% to 60%, preferably from 0.1% to 40% and in particular from 0.1% to 30% by weight of zeolite having a shape selectivity are used.

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 catalyst being often between 0.7% and 80% by weight. preferably between 1% and 50% by weight, and more preferably between 5% and 40% by weight.

In the case where several zeolites are used, they can be incorporated in a single matrix or in several different matrices. The zeolite content having a shape selectivity in the total inventory is less than 30% by weight.

The catalyst used in the catalytic cracking reactor may consist of an ultra-stable type Y zeolite dispersed in a matrix of alumina, silica, or silica-alumina, to which is added a zeolite additive ZSM5, the amount of ZSM5 crystals in the total inventory being less than 30% by weight.

DESCRIPTION OF THE FIGURE

Figure 1 illustrates the invention.

It comprises a deep hydroconversion section A in which the deep hydroconversion stage a) is carried out. The feedstock 1 is converted to the presence of hydrogen 2 and the resulting effluent 3 is separated (step b, possibly followed by step b ') into the separation section B. A light fraction 4 and a heavy fraction are obtained. 5. The latter is sent to the deep hydroconversion section C where it undergoes step c) of deep hydroconversion in the presence of hydrogen 6. From the resulting effluent 7 is separated a light fraction 8 and a heavy fraction 9 which is directed to the deasphalting section E where the deasphalting step e) is carried out with the aid of a solvent 12. The deasphalted oil DAO 10 is sent to a conversion section F where the conversion step f) takes place and the asphalt 1 1 is recovered. The effluent 13 from the conversion step f) is then generally sent to a separation step so as to recover the recoverable cuts, for example gasoline and gas oil.

Examples:

Examples 1 and 2 are compared with iso-conversion (75% of 540 ° C + 540 ° C) and Examples 3 and 4 are made at isothermal temperature. Examples 5 and 6 are compared with iso-conversion (75% of 540 ° C + 540 ° C) and Examples 7 and 8 are carried out at isothermal temperature.

Charge

The heavy load is a vacuum residue (RSV) from an Ural crude and whose main characteristics are presented in Table 1 below. This RSV heavy load is the same fresh load for the different examples.

Table 1: Composition of the process load

EXAMPLE 1 non-compliant with the invention: Diagram with high hourly space velocity and high temperature (global WH = 0.3 h ¹ + 431/431 ° C.) + deasphalting step (SDA)

In this example, two bubbling bed reactors (first and second deep hydroconversion sections) are arranged in series, operated at high space velocity (WH) and high temperature with interstage separation section and downstream deasphalting process.

Hydroconversion Section A

The fresh feed of Table 1 is sent entirely into the first boiling bed hydroconversion section A, in the presence of hydrogen which comprises a three-phase reactor a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas.

The conditions applied in the hydroconversion section A are shown in Table 2.

Table 2: Operating conditions of the hydroconversion section A

These operating conditions make it possible to obtain a liquid effluent with a reduced Conradson carbon content, in metals and in sulfur.

Separation section B

The liquid effluent from section A is then sent to a separation section B composed of a single gas / liquid separator operating at the pressure and at the temperature of the reactor of the first hydroconversion section A. A so-called light fraction and a so-called heavy fraction are thus separated. The so-called light fraction is mainly composed of molecules with a boiling point below 350 ° C and the so-called heavy fraction is mainly composed of hydrocarbon molecules boiling at a temperature of at least 350 ° C.

Hydroconversion Section C

The heavy fraction from the separation section B is sent alone and entirely into a second hydroconversion section C in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas.

The conditions applied in the hydroconversion section C are shown in Table 4.

Table 4: Operating conditions of the hydroconversion section C

Splitting section D

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields relative to the fresh load and the quality are given in Table 5 below.

Table 5: Yield and Quality of RSV from Fractionation Section D

Deasphalting section E

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit are described in Table 6. Table 6: Operating Conditions in SDA Unit E

At the end of section E, a DAO fraction is obtained that can be recovered in a conversion process (fixed-bed hydrocracking, FCC or recycling to the hydroconversion process under soft ebullated bed conditions) and a so-called "asphalt" fraction. difficult to valorize. The yields and qualities of these two products are given in Table 7. Table 7: Yields and qualities of effluents from the deasphalting section E

Overall performance

With this scheme not according to the invention, for an overall hourly space velocity (WH) of 0.3 h ¹ and high temperatures (431/431 ° C), the conversion of the heavy cut 540 ° C + is 75, 1% weight before the deasphalting step. In addition, the unconverted RSV contains significant contents of Conradson carbon and C ₇ asphaltenes (respectively 22.2% weight and 9.4% weight) implying that only 49.9% weight of the unconverted RSV is recoverable in the form of DAO . Thus, this conventional scheme is accompanied by a significant asphalt generation of 9.7% by weight relative to the fresh feedstock. If the DAO cut is then fully converted into a hydrocracking unit, the total conversion of the heavy cut 540 ° C + in the complete scheme is 87.5% wt. EXAMPLE 2 According to the Invention: Scheme according to the invention at low hourly space velocity (global WH = 0.089 h ¹ + 41 1/41 1 ° C) and at low temperature + SDA

In this example, the present invention is illustrated in a flow diagram with two series bubbling reactors arranged in series, operated at low hourly space velocity (WH = 0.089h ¹ ) and at low temperature (41 1/41 1 ° C). and with an interstage separation section and a downstream deasphalting process, as described in connection with Figure 1.

Hydroconversion Section A

The fresh feed of Table 1 is sent entirely into the first boiling bed hydroconversion section A, in the presence of hydrogen which comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight. and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas.

The conditions applied in the hydroconversion section A are shown in Table 8.

Table 8: Operating conditions of the hydroconversion section A

Section of B

The liquid effluent from section A is then sent to a separation section B composed of a single gas / liquid separator operating at the pressure and at the temperature of the reactors of the first hydroconversion section A. A so-called light fraction and a so-called heavy fraction are thus separated. The so-called light fraction is mainly composed of molecules with a boiling point below 350 ° C and the so-called heavy fraction is mainly composed of hydrocarbon molecules boiling at a temperature of at least 350 ° C. Hydroconversion Section C

The heavy fraction from the separation section B is sent alone and entirely into a second boiling bed hydroconversion section C in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas.

The conditions applied in the hydroconversion section C are shown in Table 9.

Table 9: Operating conditions of the hydroconversion section C

Splitting section D

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields relative to fresh feed and quality are given in Table 10 below.

Table 10: Yield and Quality of the RSV from Fractionation Section D

Deasphalting section E

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit described in Table 11.

Table 1 1: Operating conditions in unit E of SDA

At the end of section E, a DAO fraction is obtained that can be recovered in a conversion process (fixed-bed hydrocracking, FCC or recycling to the hydroconversion process under soft ebullated bed conditions) and a so-called "asphalt" fraction. difficult to valorize.

The yields and qualities of these two products are given in Table 12. Table 12: Efficiency and quality of effluents from the deasphalting section E

Overall performance

With this scheme according to the invention at WH total = 0.089 h ¹ conversion of the heavy cut 540 ° C + is 75.2% by weight before the deasphalting step, comparable to Example 1.

However, the unconverted RSV contains lower levels of Conradson and C7 asphaltene carbon compared to Example 1 which makes it possible to recover a larger amount of DAO from the unconverted RSV (68.2% recoverable weight in this example against 49.9% weight in Example 1). Thus, this scheme according to the invention is accompanied by a lower asphalt generation corresponding to 6.1% by weight relative to the fresh feedstock. If all of the DAO is converted into a hydrocracking unit, then an overall conversion of 92.1% by weight of the heavy cut 540 ° C + of departure can thus be obtained by means of this example according to the invention, ie 4 , 6 conversion points more than in Example 1. The scheme according to the invention therefore allows to exceed a conversion of 90% by weight relative to the fresh load.

EXAMPLE 3 Non-Conforming to the Invention: Diagram with high hourly space velocity and moderate temperature (global WH = 0.3 h ¹ + 420/420 ° C.) + SDA deasphalting step

In this example, one operates with two bubbling bed reactors arranged in series (first and second deep hydroconversions), operated at high space velocity (WH) and at moderate temperature (420 ° C) with an inter-floor separation section and a downstream deasphalting process. Hydroconversion Section A

The fresh feed from Table 1 is sent entirely into a boiling bed hydroconversion section A in the presence of hydrogen. The three-phase reactor contains a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in hydroconversion section A are shown in Table 13.

Table 13: Operating conditions of the hydroconversion section A

Separation section B

The liquid effluent from section A is then sent to a separation section B composed of a single gas / liquid separator operating at the pressure and at the temperature of the reactors of the first hydroconversion section A. A so-called light fraction and a so-called heavy fraction are thus separated. The so-called light fraction is mainly composed of molecules with a boiling point below 350 ° C and the so-called heavy fraction is mainly composed of hydrocarbon molecules boiling at a temperature of at least 350 ° C.

Hydroconversion Section C

The heavy fraction from the separation section B is sent alone and entirely into a second boiling bed hydroconversion section C in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section C are shown in Table 14.

Table 14: Operating conditions of the hydroconversion section C

Splitting section D

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields relative to the fresh load and the quality are given in Table 15 below.

Table 15: Yield and Quality of the RSV from Fractionation Section D

Deasphalting section E

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit described in Table 16. Table 16: Operating Conditions in SDA Unit E

At the end of section E, a DAO fraction is obtained that can be upgraded in a conversion process (hydrocracking, FCC or recycling to the hydroconversion process) and a so-called "asphalt" fraction that is difficult to valorize. The yields and qualities of these two products are given in Table 17.

Table 17: Efficiency and quality of effluents from the deasphalting section E

Overall performance

With this scheme, for an overall hourly space velocity (WH) of 0.3 h ¹ and moderate temperatures (420/420 ° C), the conversion of the heavy cut 540 ° C + is 59.2% wt. deasphalting step. In addition, the unconverted RSV contains high levels of Conradson carbon and C ₇ asphaltenes (respectively 20.7% by weight and 8.2% by weight) implying that only 54.1% by weight of the unconverted RSV is recoverable in the form of DAO. . Thus, this conventional scheme is accompanied by a significant asphalt generation of 14.6% by weight relative to the fresh feedstock. Even if all the DAO is converted into a hydrocracking unit, this sequence according to the prior art only corresponds to an overall conversion of 81.3% by weight of the initial heavy cut 540 ° C +. It therefore does not allow to reach conversion levels of the heavy cut 540 ° C + greater than 90% weight. EXAMPLE 4 According to the Invention: Scheme according to the invention at low hourly space velocity (global WH = 0.089 h ¹ + 420/420 ° C.) and at low temperature + SDA deasphalting step

In this example, the present invention is illustrated in a flow diagram with two series bubbling reactors arranged in series, operated at a low hourly space velocity (WH = 0.089h ¹ ) and at a moderate temperature (420/420 ° C) and with an interstage separation section and a downstream deasphalting process according to the scheme of Figure 1.

Hydroconversion Section A

The fresh feed from Table 1 is sent entirely into a boiling bed hydroconversion section A in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section (A) are presented in Table 18.

Table 18: Operating conditions of the hydroconversion section A

Separation section B

The liquid effluent from section A is then sent to a separation section B composed of a single gas / liquid separator operating at the pressure and at the temperature of the reactors of the first hydroconversion section A. A so-called light fraction and a so-called heavy fraction are thus separated. The so-called light fraction is mainly composed of molecules with a boiling point of less than 350 ° C. and the so-called heavy fraction is composed of hydrocarbon molecules boiling at a temperature of at least Hydroconversion Section C

In this reference scheme, the heavy fraction) coming from the separation section B is sent alone and entirely into a second bubbling bed hydroconversion section C in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section C are shown in Table 19.

Table 19: Operating Conditions of the Hydroconversion Section C

Splitting section D

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields relative to the fresh load and the quality are given in Table 20 below.

Table 20: Yield and Quality of the RSV from Fractionation Section D

Deasphalting section (E)

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit described in Table 21.

Table 21: Operating Conditions in SDA Unit E

At the end of section E, a DAO fraction is obtained that can be upgraded in a conversion process (hydrocracking, FCC or recycling to the hydroconversion process) and a so-called "asphalt" fraction that is difficult to valorize. The yields and qualities of these two products are given in Table 22. Table 22: Efficiency and quality of effluents from the deasphalting section E

Overall performance

With this scheme according to the invention at WH total = 0.089 h ¹ and at a moderate temperature (420/420 ° C), the conversion of the heavy cut 540 ° C + is 86.1% by weight before the deasphalting step, either greater than 26.9% by weight relative to Example 3 at the same temperature level. The amount of unconverted RSV recovered in Example 4 is thus about 3 times lower. In addition, the unconverted RSV of Example 4 contains lower levels of Conradson and C ₇ asphaltene carbon compared to Example 3, which makes it possible to recover a larger amount of DAO from the unconverted RSV. (66.8% recoverable weight in this example against 54.1% weight in Example 3). Thus, this scheme according to the invention is accompanied by a lower asphalt generation corresponding to only 3.6% by weight relative to the fresh feedstock. If all of the DAO is converted into a hydrocracking unit, a very high conversion of the heavy cut 540 ° C + of 95.4% by weight can be obtained using this scheme according to the invention.

EXAMPLE 5 Not in Accordance with the Invention: Schematic diagram at high hourly space velocity and high temperature (global WH = 0.3 h ¹ + 431/431 ° C.) + deasphalting step (SDA) + conversion step from DAO to FCC

In this example, two bubbling bed reactors (first and second deep hydroconversion sections) are arranged in series, operated at high hourly space velocity (WH) and high temperature with an inter-stage separation section and a deasphalting process. downstream. The CAD cut is then converted into an FCC unit. Hydroconversion Section (Al

The fresh feed of Table 1 is sent entirely into the first boiling bed hydroconversion section A, in the presence of hydrogen which comprises a three-phase reactor a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section A are presented in Table 2. These operating conditions make it possible to obtain a liquid effluent with a reduced Conradson carbon content, in metals and in sulfur.

Separation section (B)

Hydroconversion section (O

The heavy fraction from the separation section B is sent alone and entirely into a second hydroconversion section C in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section C are shown in Table 4.

Splitting section (D)

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields in relation to fresh feed and quality are given in Table 5. Deasphalting section (El

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit are described in Table 6. At the end of section E, a DAO fraction and a so-called "asphalt" fraction difficult to valorize. The yields and qualities of these two products are given in Table 7.

DAO conversion section (Fl

The DAO fraction from the deasphalting section E is then sent to a fluidized catalytic cracking unit, also called FCC. This conversion unit makes it possible to transform the DAO fraction, which is a 540 ° C + cut, into lighter fractions. This therefore makes it possible to increase the overall conversion of the feedstock (the vacuum residue (RSV) from an Ural crude whose characteristics are presented in Table 1). On the other hand, the liquid fraction from the FCC unit still contains a small unconverted fraction 540 ° C + whose efficiency is 1.1% by weight with respect to the FCC charge, as shown in Table 23. Compared to example 1, where all the DAO has been converted into a hydrocracking unit, the conversion of the DAO is here not total.

Table 23: Yields and qualities of effluents from the FCC F unit

Overall performance

With this scheme not according to the invention, for an overall hourly space velocity (WH) of 0.3 h ¹ and high temperatures (431/431 ° C), the conversion of the heavy cut 540 ° C + is 75, 1% weight before the deasphalting step. The unconverted RSV contains high levels of Conradson carbon and C ₇ asphaltenes (respectively 22.2% weight and 9.4% weight) implying that only 49.9% by weight of unconverted RSV is recoverable in the form of DAO. Thus, this conventional scheme is accompanied by a significant asphalt generation of 9.7% by weight relative to the fresh feedstock. The CAD cut is here converted into an FCC unit. With this flow diagram not according to the invention, for an overall hourly space velocity (WH) of 0.30 h ¹ and high temperatures (431/431 ° C.), the overall conversion of the heavy cut 540 ° C. in the complete scheme is 86.8% weight. EXAMPLE 6 According to the Invention: Scheme according to the invention at low hourly space velocity (global WH = 0.089 h ¹ + 41 1/411 ° C.) and at low temperature + deasphalting step (SDA) + DAO conversion step in FCC

In this example, the present invention is illustrated in a flow diagram with two series bubbling reactors arranged in series, operated at low hourly space velocity (WH = 0.089h ¹ ) and at low temperature (411/411 ° C) and with an interstage separation section and a downstream deasphalting process, as described in connection with Figure 1. The CAD cut is then converted into an FCC unit.

Hydroconversion Section (Al

The fresh feed of Table 1 is sent entirely into the first boiling bed hydroconversion section A, in the presence of hydrogen which comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight. and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section A are shown in Table 8.

Separation section (B)

Hydroconversion section (O

The heavy fraction from the separation section B is sent alone and entirely into a second boiling bed hydroconversion section C in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. These Operating conditions make it possible to obtain a liquid effluent with a reduced Conradson carbon content, in metals and in sulfur. The conditions applied in the hydroconversion section C are shown in Table 9.

Splitting section (Dl

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields in relation to fresh feed and quality are given in Table 10.

Deasphalting section (E)

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit described in Table 11. At the end of section E, a DAO fraction and a fraction are obtained. so-called "asphalt" difficult to valorize. The yields and qualities of these two products are given in Table 12.

DAO conversion section (Fl

The DAO fraction from the deasphalting section E is then sent to a fluidized catalytic cracking unit, also called FCC. This conversion unit makes it possible to transform the DAO fraction, which is a 540 ° C + cut, into lighter fractions. This therefore makes it possible to increase the overall conversion of the feedstock (the vacuum residue (RSV) from an Ural crude whose characteristics are presented in Table 1). On the other hand, the liquid fraction from the FCC unit still contains a small unconverted fraction 540 ° C +, the yield of which is 1.2% by weight with respect to the FCC charge, as shown in Table 24. Compared to Example 2, where all the DAO has been converted into a hydrocracking unit, the conversion of the DAO is here not total.

Table 24: Efficiency and Effectiveness of Effluents from the FCC F Unit

Overall performance

With this scheme according to the invention at WH total = 0.089 h ^1, the conversion of the heavy cut 540 ° C + is 75.2% by weight before the deasphalting step, which is comparable to Example 5. However, the RSV no converted contains lower contents of Conradson carbon and C7 asphaltenes compared to Example 5 which allows to recover a larger amount of DAO from the unconverted RSV (68.2% recoverable weight in this example against 49, 9% by weight in Example 5). Thus, this scheme according to the invention is accompanied by a lower asphalt generation corresponding to 6, 1% by weight relative to the fresh feedstock. The CAD cut is here converted into an FCC unit. With this scheme of linking according to the invention, for an overall hourly space velocity (WH) of 0.089 h ¹ and low temperatures (41 1/41 1 ° C), the overall conversion of the heavy cut 540 ° C + in the complete scheme is 91.0% by weight relative to the heavy cut 540 ° C + starting, or 4.2 conversion points more than in Example 5. The scheme according to the invention therefore allows to exceed a conversion of 90 % weight compared to the fresh load.

EXAMPLE 7 Not in Accordance with the Invention: Diagram with high space velocity at a moderate temperature (global WH = 0.3 h ¹ + 420/420 ° C.) + deasphalting step (SDA) + conversion step of DAO into FCC

In this example, one operates with two bubbling bed reactors arranged in series (first and second deep hydroconversions), operated at high space velocity (WH) and at moderate temperature (420 ° C) with an inter-floor separation section and a downstream deasphalting process. The CAD cut is then converted into an FCC unit.

Hydroconversion section (A)

The fresh feed from Table 1 is sent entirely into a boiling bed hydroconversion section A in the presence of hydrogen. The three-phase reactor contains a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section A are shown in Table 13. These operating conditions make it possible to obtain a liquid effluent with a reduced Conradson carbon content, in metals and in sulfur.

Separation section (B)

Hydroconversion section (O

Splitting section (DI

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields relative to the fresh feed and the quality are given in Table 15.

Deasphalting section (El

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit described in Table 16. At the end of section E, a DAO fraction and a fraction are obtained. so-called "asphalt" difficult to valorize. The yields and qualities of these two products are given in Table 17. PAO conversion section (Fl

The DAO fraction from the deasphalting section E is then sent to a fluidized catalytic cracking unit, also called FCC. This conversion unit makes it possible to transform the DAO fraction, which is a 540 ° C + cut, into lighter fractions. This therefore makes it possible to increase the overall conversion of the feedstock (the vacuum residue (RSV) from an Ural crude whose characteristics are presented in Table 1). In contrast, the liquid fraction from the FCC unit still contains a small, unconverted 540 ° C + fraction that has a yield of 1.9% by weight relative to the FCC charge, as shown in Table 25. Compared to example 3, where all the DAO has been converted into a hydrocracking unit, the conversion of the DAO is here not total.

Table 25: Yields and qualities of effluents from the FCC F unit

Overall performance

With this scheme, for an overall hourly space velocity (WH) of 0.3 h ¹ and moderate temperatures (420/420 ° C), the conversion of the heavy cut 540 ° C + is 59.2% wt. deasphalting step. In addition, the unconverted RSV contains high levels of Conradson carbon and C ₇ asphaltenes (respectively 20.7% by weight and 8.2% by weight) implying that only 54.1% by weight of the unconverted RSV is recoverable in the form of DAO. . Thus, this conventional scheme is accompanied by a significant asphalt generation of 14.6% by weight relative to the fresh feedstock. The CAD cut is here converted into an FCC unit. With this flow diagram not according to the invention, for an overall hourly space velocity (WH) of 0.30 h ¹ and moderate temperatures (420/420 ° C.), the overall conversion of the heavy cut 540 ° C. in the complete scheme is 80.0% weight. This sequence according to the prior art therefore does not allow to reach conversion levels of the heavy cut 540 ° C + greater than 90% by weight. EXAMPLE 8 According to the Invention: Scheme according to the invention at a low hourly space velocity (global WH = 0.089 h ¹ + 420/420 ° C.) and at a low temperature + a deasphalting step (SDA) + a step for converting the DAO into FCC

In this example, the present invention is illustrated in a flow diagram with two series bubbling reactors arranged in series, operated at a low hourly space velocity (WH = 0.089h ¹ ) and at a moderate temperature (420/420 ° C) and with an interstage separation section and a downstream deasphalting process, according to the scheme of Figure 1. The CAD cut is then converted into an FCC unit.

Hydroconversion section (A)

The fresh feed from Table 1 is sent entirely into a boiling bed hydroconversion section A in the presence of hydrogen. Said section comprises a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 4% by weight and a MoO ₃ content of 9% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed with an upward flow of liquid and gas. The conditions applied in the hydroconversion section (A) are presented in Table 18. These operating conditions make it possible to obtain a liquid effluent with a reduced Conradson carbon content, in metals and in sulfur.

Separation section (B)

The liquid effluent from section A is then sent to a separation section B composed of a single gas / liquid separator operating at the pressure and at the temperature of the reactors of the first hydroconversion section A. A so-called light fraction and a so-called heavy fraction are thus separated. The so-called light fraction is mainly composed of molecules with a boiling point below 350 ° C. and the so-called heavy fraction is composed of hydrocarbon molecules boiling at a temperature of at least 350 ° C.

Hydroconversion section (C)

Splitting section (DI

The effluent from the hydroconversion section C is sent to a fractionation section D composed of an atmospheric distillation followed by a distillation under vacuum from which an unconverted heavy residue residue (RSV) boiling at a temperature of at least 540 ° C whose yields in relation to the fresh load and the quality are given in Table 20.

Deasphalting section (El

The vacuum residue from section D is sent to the deasphalting section E. The conditions applied in the deasphalting unit described in Table 21. At the end of section E, a recoverable DAO fraction is obtained. in a conversion process (hydrocracking, FCC or recycling to the hydroconversion process) and a so-called "asphalt" fraction that is difficult to valorize. The yields and qualities of these two products are given in Table 22.

DAO conversion section (Fl

The DAO fraction from the deasphalting section E is then sent to a fluidized catalytic cracking unit, also called FCC. This conversion unit makes it possible to transform the DAO fraction, which is a 540 ° C + cut, into lighter fractions. This therefore makes it possible to increase the overall conversion of the feedstock (the vacuum residue (RSV) from an Ural crude whose characteristics are presented in Table 1). On the other hand, the liquid fraction from the FCC unit still contains a small unconverted 540 ° C + fraction whose yield is 1.2% by weight with respect to the FCC charge, as shown in Table 26. Compared to Example 4, where all the DAO has been converted into a hydrocracking unit, the conversion of the DAO is here not total. Table 26: Yields and qualities of effluents from the FCC F unit

Overall performance

With this scheme according to the invention at WH total = 0.089 h ¹ and at a moderate temperature (420/420 ° C), the conversion of the heavy cut 540 ° C + is 86.1% by weight before the deasphalting step, either greater than 26.9% by weight relative to Example 7 at the same temperature level. The amount of unconverted RSV recovered in Example 4 is thus about 3 times lower. In addition, the unconverted RSV of Example 8 contains lower levels of Conradson and C ₇ asphaltene carbon compared to Example 7, which allows a larger amount of DAO to be recovered from the unconverted RSV. (66.8% recoverable weight in this example against 54.1% weight in Example 7). Thus, this scheme according to the invention is accompanied by a lower asphalt generation corresponding to only 3.6% by weight relative to the fresh feedstock. The CAD cut is here converted into an FCC unit. With this wiring scheme according to the invention, for an overall hourly space velocity (WH) of 0.089 h ¹ and moderate temperatures (420/420 ° C), the overall conversion of the heavy cut 540 ° C + in the diagram 94.4% by weight relative to the heavy cut 540 ° C + of departure, or 14.4 conversion points more than in Example 7. The scheme according to the invention therefore allows to exceed a conversion of 90 % weight compared to the fresh load.

Other solvents such as pentane (C5) can be used in the deasphalting process in place of butane (C4) as described herein in these 8 examples. Deasphalting with C5 makes it possible to increase the yields of DAO and to exacerbate the advantages of the invention.

Claims

A process for converting hydrocarbon feeds of which at least 50%, preferably at least 80% by weight, at a temperature of at least 300 ° C, comprising the following successive steps:

in a step a), a first deep hydroconversion of said hydrocarbon feedstock is carried out in the presence of hydrogen at an absolute pressure of between

2 MPa and 35 MPa, at a temperature between 300 ° C and 550 ° C, with a quantity of hydrogen of between 50 Nm ³ / m ³ and 5000 Nm ³ / m ³ , with a catalyst containing at least one metal of group VIII chosen from nickel and cobalt and at least one Group VIB metal selected from molybdenum and tungsten, optionally a step b) of separating a light fraction from a part or all of the effluent from said first hydroconversion, and at least one heavy fraction of which at least 80% by weight has a boiling point of at least 250 ° C,

the overall hourly space velocity for steps a) to c) is less than 0.1 h ¹ , the overall speed being the liquid feed rate of hydroconversion step a) taken under standard conditions of temperature and pressure , based on the total volume of reactors in steps a) and c),

a step d) of separating part or all of the effluent resulting from said second hydroconversion into at least one light fraction and at least one heavy fraction of which at least 80% by weight has a boiling point of at least 300 ° C,

a step e) of deasphalting said heavy fraction resulting from step d) at a temperature of between 60 ° C. and 250 ° C. with at least one hydrocarbon solvent having

3 to 7 carbon atoms, and a solvent / filler ratio (volume / volume) of between 4/1 and 9/1, and a deasphalted DAO fraction and an asphalt are obtained. 2- A method according to claim 1 comprising a step f) of converting a portion or all of said distilled DAO fraction possibly distilled.

3. Process according to claim 2, in which the DAO is distilled before the conversion step f) in order to separate a heavy fraction of which at least 80% by weight has a boiling point of at least 375 ° C., or at least 400 ° C, or at least 450 ° C or at least 500 ° C, and preferably at least 540 ° C, and said heavy fraction sent partly or wholly in the step f) conversion.

4- Method according to one of the preceding claims wherein a part or all of the DAO fraction is sent, preferably directly, in a conversion step operating with a process selected from the group formed by the hydrocracking in a fixed bed, catalytic cracking in a fluidized bed, bubbling bed hydroconversion, these processes possibly comprising prior hydrotreatment.

5. The process as claimed in claim 4, in which part or all of the deasphalted fraction DAO is hydrocracked in a fixed bed, in the presence of hydrogen, at an absolute pressure of between 5 MPa and 35 MPa, at a temperature of advantageously between 300 and 500 ° C, WH between 0, 1 ¹ h and 5 h ^1, and a quantity of hydrogen ranging from 100 Nm ³ / m ³ and 1000 Nm ³ / m ³ of liquid feed, and in the presence of a catalyst containing at least one non-noble group VIII element and at least one group VIB element and comprising a support containing at least one zeolite.

The process according to claim 4 wherein a part or all of the deasphalted fraction DAO is subjected to FCC fluidized catalytic cracking in the presence of a catalyst, preferably free of metals, comprising alumina, silica, silica-alumina, and preferably comprising at least one zeolite. 7- Process according to claim 4 wherein a part or all of the deasphalted fraction DAO is subjected to a bubbling bed hydroconversion, carried out in the presence of hydrogen, at an absolute pressure of between 2 MPa and 35 MPa, at a temperature between 300 ° C and 550 ° C, a quantity of hydrogen between

-1 -1

50 Nm ³ / m ³ and 5000 Nm ³ / m ³ of liquid filler, a WH of between 0.1 h and 10 h and in the presence of a catalyst containing a support and at least one metal of group VIII chosen from nickel and cobalt and at least one Group VI B metal selected from molybdenum and tungsten.

8- Method according to one of the preceding claims wherein at least a portion of said deasphalted fraction DAO is recycled in step a) and / or in step c).

9- Method according to one of the preceding claims wherein in step d) separation, the effluent from said second hydroconversion is separated into at least a light fraction and at least a heavy fraction of which at least 80% present weight a boiling temperature of at least 375 ° C, or at least 400 ° C, or at least 450 ° C or at least 500 ° C, and preferably at least 540 ° C .

10- Method according to one of the preceding claims wherein

the steps a) and c) are carried out under an absolute pressure of between 5 MPa and 25 MPa and, preferably, between 6 MPa and 20 MPa, at a temperature of between 350 ° C. and 500 ° C. and in a manner preferred between 370 ° C and 430 ° C, and more preferably between 380 ° C and 430 ° C, with a quantity of hydrogen of between 100 Nm ³ / m ³ and 2000 Nm ³ / m ³ and very preferably between 200 Nm ³ / m ³ and 1000 Nm ³ / m ³ , the hourly space velocity (WH) being at least 0.05 h ¹ , preferably between 0.05 h ¹ and 0.09 h ¹ ,

step e) is carried out with a solvent chosen from the group formed by butane, pentane or hexane, as well as their mixtures.