EP3415588B1 - Two-stage hydrocracking integrated process and hydroprocessing process - Google Patents

Description

Hydrocracking of heavy petroleum fractions is a key refining process which makes it possible to produce, from excess heavy and little recoverable charges, the lighter fractions such as gasolines, jet fuels and light gas oils that the refiner seeks to adapt its production to the request. Certain hydrocracking processes also make it possible to obtain a highly purified residue which can constitute excellent bases for oils or a feedstock which can be easily upgraded in a catalytic cracking unit for example. One of the effluents particularly targeted by the hydrocracking process is the middle distillate (fraction which contains the diesel cut and the kerosene cut).

The hydrocracking process of vacuum distillates or DSV makes it possible to produce light cuts (Diesel, Kerosene, naphthas, ...) more valuable than the DSV itself. This catalytic process does not entirely transform the DSV into light cuts. After fractionation, there remains a more or less significant proportion of fraction of unconverted DSV called UCO or UnConverted Oil according to the English terminology. To increase the conversion, this unconverted fraction can be recycled at the inlet of the hydrotreating reactor or at the inlet of the hydrocracking reactor. The recycling of the fraction not converted at the inlet of the hydrotreatment reactor or at the inlet of the hydrocracking reactor makes it possible both to increase the conversion, but also makes it possible to increase the selectivity in terms of gas oil and kerosene. Another way to increase the conversion while maintaining the selectivity is to add a conversion or hydrocracking reactor on the recycle loop of the fraction not converted to the high pressure separation section. This reactor and the associated recycle constitutes a second hydrocracking step. This reactor being located downstream of the fractionation section, it operates with little sulfur (H ₂ S) and little nitrogen, which makes it possible to use catalysts less sensitive to the presence of sulfur by increasing the selectivity of the process.

Indeed, hydrocracking two stages, comprises a first stage which aims, as in the "one stage" process, to carry out the hydrorefining of the feedstock but also to achieve a conversion of the latter of the order in general from 30 to 70%. The effluent from the first stage then undergoes fractionation (distillation), which aims to separate the conversion products from the unconverted fraction. In the second stage of a 2-stage hydrocracking process, only the fraction of the feedstock not converted during the first stage, is treated. This separation allows a two-stage hydrocracking process to be more selective in diesel than a one-step process with equivalent overall conversion rate. In fact, the intermediate separation of the conversion products avoids their "over-cracking" into naphtha and gas in the second step on the hydrocracking catalyst. Furthermore, it should be noted that the unconverted fraction of the charge treated in the second step generally contains very low contents of NH ₃ as well as organic nitrogen compounds, in general less than 20 ppm by weight or even less than 10 ppm by weight.

The diesel hydrodesulfurization process makes it possible to reduce the quantity of sulfur contained in a diesel cut while minimizing the conversion of the feedstock into lighter products (gas, naphtha). The hydrodesulfurization charge can consist of straight run diesel according to the English terminology or diesel fuel resulting from the atmospheric fractionation of a crude oil, Light Vacuum Gasoil Oil according to the English terminology or light vacuum distillate, LCO or distillate from a conversion process (FCC, coker, etc.), from a diesel charge resulting from the conversion of biomass (esterification for example), alone or as a mixture, for example. The partial pressure of hydrogen required for this process is lower than the partial pressure of hydrogen in the hydrocracker. It is common for these two processes to be present in the same refinery without being integrated. However, they are based on very similar process diagrams, consisting of a charge furnace, fixed bed reactors, hydrogen recycle compressors, and more or less complex high pressure separation sections.

US 2006/131212 A1 describes a hydrocracking process of vacuum distillates in two stages, in which the charge of the vacuum distillate type is introduced into a first hydrocracking stage comprising at least one catalytic bed comprising at least one hydrotreating catalyst in which the reactions hydrotreating takes place followed by at least one catalytic bed comprising at least one hydrocracking catalyst in which the hydrocracking reactions take place. The unconverted effluent from the first hydrocracking step is then sent after several separation steps, in a second hydrocracking step, only in mixture with hydrogen, said second hydrocracking step comprising a first zone Q comprising hydrocracking catalysts, this section operating cocurrently. The second hydrocracking stage also includes a second zone operating against the current so as to create an environment favorable to the saturation of the aromatics and to hydrocracking.

• limiter le craquage de la charge de type gazole dans l'étape d'hydrotraitement et de maximiser la sélectivité du procédé,
• limiter la concentration en azote et en soufre dans l'étape d'hydrotraitement de la charge de type gazole en mélange avec l'effluent de la seconde étape d'hydrocraquage, ce qui optimise ladite étape,
• en plus de désulfurer la charge de type gazole, de minimiser la formation de produits lourds polyaromatiques (HPNA), ce qui permet de limiter la purge de la bouche de seconde étape d'hydrocraquage et donc d'augmenter la conversion du procédé, et
• en plus de désulfurer la charge de type gazole, de convertir la partie non convertie issue de la deuxième étape d'hydrocraquage e), ce qui permet de réduire la quantité de catalyseur utilisée dans ladite étape e) d'hydrocraquage, à iso conversion par passe de l'étape constituée de la combinaison de la deuxième étape d'hydrocraquage e) et de l'étape f) d'hydrotraitement.

The invention consists in integrating a two-stage hydrocracking process with a hydrodesulphurization process for gas oils by using at least part of the reactor of the second hydrocracking step to desulphurize the gas oil feed mixed with the unconverted fraction or UCO . The applicant's research work led him to discover that the co-treatment of the mixture constituted by the effluent of the second stage of a two-stage hydrocracking process treating a charge of DSV type, with a charge of diesel fuel type , in a hydrotreatment step allows, compared to the co-treatment of a VGO type feedstock and a diesel fuel type feedstock, directly mixed in a two-step hydrocracking process, of:

• limit the cracking of the diesel type feedstock in the hydrotreatment step and maximize the selectivity of the process,
• limit the nitrogen and sulfur concentration in the hydrotreatment step of the diesel-type feedstock in admixture with the effluent of the second hydrocracking step, which optimizes said step,
• in addition to desulfurizing the diesel-type feedstock, minimizing the formation of heavy polyaromatic products (HPNA), which makes it possible to limit the purging of the mouth of the second hydrocracking step and therefore to increase the conversion of the process, and
• in addition to desulfurizing the feedstock of the diesel type, to convert the unconverted part resulting from the second hydrocracking step e), which makes it possible to reduce the amount of catalyst used in said hydrocracking step e), with iso-conversion by pass of the step consisting of the combination of the second hydrocracking step e) and of step f) of hydrotreating.

• réduire l'investissement initial et la consommation de catalyseur dans la deuxième étape e) d'hydrocraquage.

The process according to the invention also makes it possible, with respect to the dedicated hydrocracking processes, two stages of DVS and hydrodesulfurization of gas oils operating separately, to:

• reduce the initial investment and the consumption of catalyst in the second hydrocracking stage e).

Summary of the invention

The present invention relates to a hydrocracking process in two stages of a hydrocarbon feedstock of the vacuum distillate type in which all of the effluent from the second hydrocracking stage e) is co-treated in a hydrotreatment stage f) located downstream of said second hydrocracking step e), in admixture with a liquid hydrocarbon feed of the gas oil type, distinct from said effluent from the second hydrocracking step e).

1. a) L'hydrocraquage desdites charges opérant, en présence d'hydrogène et d'au moins un catalyseur d'hydrocraquage, à une température comprise entre 250 et 480°C, sous une pression comprise entre 2 et 25 MPa, à une vitesse spatiale comprise entre 0,1 et 6 h-1 et à une quantité d'hydrogène introduite telle que le rapport volumique litre d'hydrogène/litre d'hydrocarbure soit compris entre 100 et 2000 L/L,
2. b) La séparation gaz/liquide de l'effluent issu de l'étape a) pour produire un effluent liquide et un effluent gazeux comprenant au moins de l'hydrogène,
3. c) L'envoi de l'effluent gazeux comprenant au moins de l'hydrogène dans une étape de compression avant son recycle dans au moins l'étape a) d'hydrocraquage,
4. d) Le fractionnement de l'effluent liquide en au moins un effluent comprenant les produits hydrocarbonés convertis ayant des points d'ébullition inférieurs à 340°C et une fraction liquide non convertie ayant un point d'ébullition supérieurs à 340°C,
5. e) L'hydrocraquage de ladite fraction liquide non convertie issue de l'étape d) opérant, en présence d'hydrogène et d'un catalyseur d'hydrocracquage comprenant une fonction hydrogénante comprenant au moins un métal du groupe VIII choisi parmi le fer, le cobalt, le nickel, le ruthénium, le rhodium, le palladium et le platine et/ou au moins un métal du groupe VIB choisi parmi le chrome, le molybdène et le tungstène, seul ou en mélange, et une fonction acide choisie parmi la silice alumine et les zéolithes, à une température comprise entre 250 et 480°C, sous une pression comprise entre 2 et 25 MPa, à une vitesse spatiale comprise entre 0,1 et 6 h-1 et à une quantité d'hydrogène introduite telle que le rapport volumique litre d'hydrogène/litre d'hydrocarbure soit compris entre 100 et 2000 L/L,
6. f) L'hydrotraitement de la totalité de l'effluent issu de l'étape e) en mélange avec une charge liquide hydrocarbonée comprenant au moins 95% poids de composés bouillants à une température d'ébullition comprise entre 150 et 400°C, distincte dudit effluent issu de la deuxième étape d'hydrocraquage e), ladite étape f) d'hydrotraitement opérant en présence d'hydrogène et d'au moins un catalyseur d'hydrotraitement comprenant au moins un support amorphe alumine et au moins un élément hydro-déshydrogénant choisi parmi au moins un élément des groupes VIB et VIII non noble, à une température comprise entre 200 et 390°C, sous une pression comprise entre 2 et 16 MPa, à une vitesse spatiale comprise entre 0,2 et 5 h-1 et à une quantité d'hydrogène introduite telle que le rapport volumique litre d'hydrogène/litre d'hydrocarbure soit compris entre 100 et 2000 L/L.

In particular, the present invention relates to a process for hydrocracking hydrocarbon feedstocks containing at least 20% by volume and preferably at least 80% by volume of compounds boiling above 340 ° C., said process comprising at least the following steps:

1. a) The hydrocracking of said feeds operating, in the presence of hydrogen and at least one hydrocracking catalyst, at a temperature between 250 and 480 ° C., under a pressure between 2 and 25 MPa, at a space speed between 0.1 and 6 h -1 and at a quantity of hydrogen introduced such that the volume ratio of liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L,
2. b) The gas / liquid separation of the effluent from step a) to produce a liquid effluent and a gaseous effluent comprising at least hydrogen,
3. c) the sending of the gaseous effluent comprising at least hydrogen in a compression stage before its recycling in at least hydrocracking stage a),
4. d) Fractionation of the liquid effluent into at least one effluent comprising the converted hydrocarbon products having boiling points below 340 ° C and an unconverted liquid fraction having a boiling point above 340 ° C,
5. e) hydrocracking of said non-converted liquid fraction resulting from step d) operating, in the presence of hydrogen and of a hydrocracking catalyst comprising a hydrogenating function comprising at least one group VIII metal chosen from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum and / or at least one metal from group VIB chosen from chromium, molybdenum and tungsten, alone or as a mixture, and an acid function chosen from alumina silica and zeolites, at a temperature between 250 and 480 ° C, under a pressure between 2 and 25 MPa, at a space speed between 0.1 and 6 h-1 and at a quantity of hydrogen introduced such that the volume ratio liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L,
6. f) The hydrotreatment of all the effluent from step e) in mixture with a liquid hydrocarbon feed comprising at least 95% by weight of boiling compounds at a boiling temperature between 150 and 400 ° C, distinct said effluent from the second hydrocracking step e), said hydrotreating step f) operating in the presence of hydrogen and at least one hydrotreatment catalyst comprising at least one amorphous alumina support and at least one hydro- dehydrogenating agent chosen from at least one non-noble element of groups VIB and VIII, at a temperature between 200 and 390 ° C, under a pressure between 2 and 16 MPa, at a space speed between 0.2 and 5 h-1 and to a quantity of hydrogen introduced such that the volume ratio of liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L.

An advantage of the present invention is to provide a process integrating a hydrocracking process in two stages with a hydrodesulfurization process of gas oils making it possible to limit the cracking of the diesel-type feedstock in the hydrotreatment step and to maximize the selectivity and yields of middle distillates from the process. - reduce the initial investment and the consumption of catalyst in the second hydrocracking stage e).

Another advantage of the present invention is to provide a process allowing, by the implementation of a co-treatment of the effluent resulting from the hydrocracking step e) in mixture with a liquid hydrocarbon feedstock of the gas oil type in a hydrotreatment stage f), downstream from the hydrocracking stage e), in addition to desulfurizing the liquid hydrocarbon feedstock of the gas oil type, to convert the unconverted part of the effluent from the hydrocracking stage e), which makes it possible to reduce the amount of catalyst used in said hydrocracking step e), with iso conversion per pass of the step consisting of the combination of the second hydrocracking step e) and of step f ) hydrotreatment,

Another advantage of the present invention is to provide a process which, by implementing said co-treatment, makes it possible, in addition to desulfurizing the liquid hydrocarbon feedstock of the gas oil type, to minimize the formation of polyaromatic heavy products (HPNA). In fact, the HPNA gradually forms during their recycling in the second hydrocracking stage. The implementation of step f) of hydrotreating downstream of step e) of hydrocracking makes it possible to limit the growth of HPNAs by hydrogenating the precursors of said HPNAs, that is to say HPNAs of low weight. molecular).

Another advantage of the present invention is to provide a process which by the integration of two processes allows the reduction of operating costs and the reduction of the consumption of catalyst in the second hydrocracking stage.

Detailed description of the invention

According to the invention, the method comprises a step a) of hydrocracking said charges operating, in the presence of hydrogen and at least one hydrocracking catalyst, at a temperature between 250 and 480 ° C, under pressure between 2 and 25 MPa, at a space speed between 0.1 and 6 h -1 and at a quantity of hydrogen introduced such that the volume ratio liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L.

The operating conditions such as temperature, pressure, hydrogen recycling rate, hourly space velocity, may be very variable depending on the nature of the feed, the quality of the desired products and the facilities available to the refiner.

Preferably, hydrocracking step a) according to the invention operates at a temperature between 320 and 450 ° C, very preferably between 330 and 435 ° C, under a pressure between 3 and 20 MPa, and very preferably between 6 and 20 MPa, at a space speed of between 0.2 and 4 h -1, very preferably between 0.3 and 5 h -1 and with an amount of hydrogen introduced such as the volume ratio liter of hydrogen / liter of hydrocarbon is between 200 and 2000 L / L.

These operating conditions used in step a) of the process according to the invention generally make it possible to achieve conversions by pass, into products having boiling points below 340 ° C, and better still below 370 ° C, greater than 15% by weight and even more preferably between 20 and 95% by weight.

In accordance with the invention, the hydrocarbon feedstocks treated in the process according to the invention and sent in step a) are chosen from hydrocarbon feedstocks containing at least 20% by volume and preferably at least 80% by volume of boiling compounds. above 340 ° C and preferably between 370 and 580 ° C (that is to say corresponding to compounds containing at least 15 to 20 carbon atoms).

Said hydrocarbon feedstocks can advantageously be chosen from VGOs (Vacuum gas oil) according to Anglo-Saxon terminology or vacuum distillates (DSV) such as for example gas oils obtained from the direct distillation of crude oil or from conversion units such as FCC, coker or visbreaking as well as fillers from aromatic extraction units from lubricating oil bases or from solvent dewaxing of lubricating oil bases, or from distillates from desulfurization or hydroconversion of RAT (atmospheric residues) and / or RSV (vacuum residues), or the feed can advantageously be a deasphalted oil, or fillers from biomass or any mixture of the fillers previously mentioned. The above list is not exhaustive. In general, said fillers have an initial boiling point greater than 340 ° C, and preferably greater than 370 ° C.

Said hydrocarbon feedstocks can contain heteroatoms such as sulfur and nitrogen. The nitrogen content is usually between 1 and 8000 ppm by weight, more generally between 200 and 5000 ppm by weight, and the sulfur content between 0.01 and 6% by weight, more generally between 0.2 and 5% and still more more preferred between 0.5 and 4% by weight.

Said charge treated in the method according to the invention and sent in step a) may optionally contain metals. The cumulative nickel and vanadium content of the charges treated in the processes according to the invention is preferably less than 1 ppm by weight.

The asphaltenes content is generally less than 3000 ppm by weight, preferably less than 1000 ppm by weight, even more preferably less than 200 ppm by weight.

In the case where the feed contains compounds of the resins and / or asphaltenes type, it is advantageous to pass the feed beforehand over a bed of catalyst or adsorbent different from the hydrocracking or hydrotreating catalyst.

According to the invention, hydrocracking step a) operates in the presence of at least one hydrocracking catalyst. Preferably, the hydrocracking catalyst is chosen from the conventional hydrocracking catalysts known to those skilled in the art.

The hydrocracking catalysts used in hydrocracking processes are all of the bifunctional type combining an acid function with a hydrogenating function. The acid function is provided by supports of large surfaces (150 to 800 m ² .g-1 generally) having a surface acidity, such as halogenated aluminas (chlorinated or fluorinated in particular), combinations of boron oxides and aluminum, amorphous silica-aluminas and zeolites. The hydrogenating function is provided either by one or more metals from group VIII of the periodic table, or by a combination of at least one metal from group VIB of the periodic table and at least one metal from group VIII.

Preferably, the hydrocracking catalyst (s) comprise a hydrogenating function comprising at least one group VIII metal chosen from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum and preferably cobalt and nickel and / or at least one metal from group VIB chosen from chromium, molybdenum and tungsten, alone or as a mixture and preferably from molybdenum and tungsten.

Preferably, the content of group VIII metal in the hydrocracking catalyst (s) is advantageously between 0.5 and 15% by weight and preferably between 2 and 10% by weight, the percentages being expressed as percentage by weight of oxides.

Preferably, the content of group VIB metal in the hydrocracking catalyst (s) is advantageously between 5 and 25% by weight and preferably between 15 and 22% by weight, the percentages being expressed as a percentage by weight of oxides.

The catalyst (s) can also optionally at least one promoter element deposited on the catalyst and chosen from the group formed by phosphorus, boron and silicon, optionally at least one element from group VIIA (chlorine, fluorine preferred), and optionally at at least one element from group VIIB (preferred manganese), optionally at least one element from group VB (preferred niobium).

Preferably, the hydrocracking catalyst (s) comprise an acid function chosen from alumina, silica alumina and zeolites, preferably chosen from zeolites Y and preferably chosen from silica alumina and zeolites.

A preferred catalyst comprises and preferably consists of at least one group VI metal and / or at least one non-noble group VIII metal, and a zeolite Y and an alumina binder.

An even more preferred catalyst comprises and preferably consists of nickel, molybdenum, a Y zeolite and alumina.

Another preferred catalyst comprises and preferably consists of nickel, tungsten and alumina or silica alumina.

In step a) of the process according to the invention, the conversion, during the first step, into products having boiling points below 340 ° C, and better still below 370 ° C, is greater than 20% and preferably greater than 30% and even more preferably between 30 and 80% and preferably between 40 and 60%.

The hydrocarbon feedstocks treated in the process according to the invention and sent in step a) can optionally be sent in a hydrotreatment step before being sent in step a) of hydrocracking of said process. In the optional hydrotreatment step, said feedstocks are advantageously desulfurized and denitrogenated.

Preferably, said hydrotreatment step is advantageously carried out under conventional hydrorefining conditions and in particular in the presence of hydrogen and a hydrotreatment catalyst and at a temperature between 200 and 400 ° C., under a pressure between 2 and 16 MPa, at a space velocity between 0.2 and 5 h-1 and at a quantity of hydrogen introduced such that the volume ratio liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L.

Conventional hydrotreatment catalysts can advantageously be used, preferably which contain at least one amorphous support and at least one hydro-dehydrogenating element chosen among at least one element from groups VIB and VIII non-noble, and most often at least one element from group VIB and at least one element from group VIII non-noble.

Preferably, the amorphous support is alumina or silica alumina.

Preferred catalysts are chosen from NiMo catalysts on alumina and NiMo or NiW catalysts on alumina silica.

The effluent from the hydrotreatment step and entering the hydrocracking step a) comprises a nitrogen content preferably less than 300 ppm by weight and preferably less than 50 ppm by weight.

In the case where a hydrotreatment step is implemented, the hydrotreatment step and the hydrocracking step a) can advantageously be carried out in the same reactor or in different reactors. In the case where they are produced in the same reactor, the reactor comprises several catalytic beds, the first catalytic beds comprising the hydrotreatment catalyst (s) and the following catalytic beds comprising the hydrocracking catalyst (s).

According to the invention, the method comprises a step b) of gas / liquid separation of the effluent from step a) to produce a liquid effluent and a gaseous effluent comprising at least hydrogen.

Preferably, step b) of gas / liquid separation is implemented in a high pressure high temperature separator operating at a temperature between 50 and 450 ° C, preferably between 100 and 400 ° C, even more preferably between 200 and 300 ° C, and a pressure corresponding to the outlet pressure of a) minus the pressure drops.

According to the invention, the method comprises a step c) of sending the gaseous effluent comprising at least hydrogen in a compression step before its recycling in at least step a) of hydrocracking. This step is necessary to allow the gas to be recycled upstream, that is to say in the hydrocracking step a), therefore at higher pressure.

The gaseous effluent comprising at least hydrogen can advantageously be mixed with make-up hydrogen before or after its introduction in compression step c), preferably via a make-up hydrogen compressor or make up according to Anglo-Saxon terminology.

According to a variant, part of the gaseous effluent comprising at least compressed hydrogen can also advantageously be sent in steps e) of hydrocracking and / or f) of hydrotreatment.

According to the invention, the method comprises a step d) of fractionating the liquid effluent from step a) into at least one effluent comprising the converted hydrocarbon products having boiling points below 340 ° C, preferably below 370 ° C and preferably below 380 ° C and an unconverted liquid fraction having a boiling point above 340 ° C, preferably above 370 ° C and preferably higher than 380 ° C also called UCO or "unconverted oil" according to English terminology.

Preferably, said step d) of fractionation comprises a first separation step comprising a separation means such as for example a separator flask or a steam stripper preferably operating at a pressure of between 0.5 and 2 MPa, which aims to achieve a hydrogen sulfide (H ₂ S) separation from at least one hydrocarbon effluent produced during step a) of hydrocracking. The hydrocarbon effluent from this first separation can advantageously undergo atmospheric distillation, and in certain cases the combination of atmospheric distillation and vacuum distillation. The purpose of distillation is to separate the converted hydrocarbon products, that is to say generally having boiling points below 340 ° C, preferably below 370 ° C and preferably below 38 ° C and an unconverted liquid fraction (residue) (UCO).

According to another variant, the fractionation step consists only of an atmospheric distillation column.

The converted hydrocarbon products having boiling points below 340 ° C, preferably below 370 ° C and preferably below 380 ° C are advantageously distilled at atmospheric pressure to obtain several fractions converted to boiling point at most 340 ° C, and preferably a C1-C4 light gas fraction, at least a gasoline fraction and at least a kerosene and diesel middle distillate fraction.

The liquid fraction, unconverted residue (UCO) containing products whose boiling point is higher than 340 ° C, preferably higher than 370 ° C and preferably higher than 380 ° C and resulting from distillation is at less in part and preferably in whole introduced into the second hydrocracking step e) of the process according to the invention.

A purge can advantageously be carried out on the residual liquid fraction in order to avoid the accumulation of heavy polyaromatic products (HPNA) present in the loop for recycling heavy cuts. Indeed, the HPNA gradually forms during their recycling in the second hydrocracking step and the recycling of these heavy aromatic components in the loop of the second hydrocracking step e) has the consequence of increasing their molecular weight. The presence of HPNA in said recycle loop ultimately leads to a significant pressure drop. A purge is therefore necessary in order to limit the accumulation of these HPNA products.

In accordance with the invention, the process comprises a step e) of hydrocracking of said unconverted liquid fraction from step d), optionally purged, operating in the presence of hydrogen and of a hydrocracking catalyst, at a temperature between 250 and 480 ° C, under a pressure between 2 and 25 MPa, at a space speed between 0.1 and 6 h -1 and at a quantity of hydrogen introduced such that the volume ratio of liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L.

Preferably, the hydrocracking step e) according to the invention operates at a temperature between 320 and 450 ° C, very preferably between 330 and 435 ° C, under a pressure between 3 and 20 MPa, and very preferably between 9 and 20 MPa, at a space velocity between 0.2 and 3 h -1, and at a quantity of hydrogen introduced such that the volume ratio of liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L.

These operating conditions used in step e) of the process according to the invention generally make it possible to achieve conversions by pass, into products having boiling points below 340 ° C, preferably below 370 ° C and so preferred below 380 ° C, above 15% by weight and even more preferably between 20 and 80% by weight. Nevertheless, the conversion by pass in step e) is kept low in order to maximize the selectivity of the process in product having boiling points between 150 and 370 ° C (middle distillates). Pass conversion is limited by the use of a high recycle rate on the second hydrocracking stage loop. This rate is defined as the ratio between the feed flow rate of step e) and the flow rate of the feed from step a), preferably this ratio is between 0.2 and 4, preferably between 0, 5 and 2.

According to the invention, hydrocracking step e) operates in the presence of at least one hydrocracking catalyst. Preferably, the second stage hydrocracking catalyst is chosen from the conventional hydrocracking catalysts known to those skilled in the art. The hydrocracking catalyst used in said step e) may be the same or different from that used in step a) and preferably different.

The hydrocracking catalysts used in hydrocracking processes are all of the bifunctional type combining an acid function with a hydrogenating function. The acid function is provided by supports of large surfaces (150 to 800 m ² .g-1 generally) having a surface acidity, such as halogenated aluminas (chlorinated or fluorinated in particular), combinations of boron oxides and aluminum, amorphous silica-aluminas and zeolites. The hydrogenating function is provided either by one or more metals from group VIII of the periodic table, or by a combination of at least one metal from group VIB of the periodic table and at least one metal from group VIII.

The hydrocracking catalyst (s) used in step e) comprise a hydrogenating function comprising at least one group VIII metal chosen from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum and preferably cobalt and nickel and / or at least one metal from group VIB chosen from chromium, molybdenum and tungsten, alone or as a mixture and preferably from molybdenum and tungsten.

Preferably, the content of group VIII metal in the hydrocracking catalyst (s) is advantageously between 0.5 and 15% by weight and preferably between 2 and 10% by weight, the percentages being expressed as percentage by weight of oxides.

Preferably, the metal content of group VIB in the hydrocracking catalyst (s) is advantageously between 5 and 25% by weight and preferably between 15 and 22% by weight, the percentages being expressed as percentage by weight of oxides.

The catalyst (s) used in step e) can also optionally comprise at least one promoter element deposited on the catalyst and chosen from the group formed by phosphorus, boron and silicon, optionally at least one element from group VIIA (chlorine , fluorine preferred), and optionally at least one element from group VIIB (manganese preferred), optionally at least one element from group VB (niobium preferred).

The hydrocracking catalyst (s) used in step e) comprise an acid function chosen from alumina, silica alumina and zeolites, preferably chosen from zeolites Y and preferably chosen from silica alumina and zeolites.

A preferred catalyst used in step e) preferably comprises at least one group VI metal and / or at least one non-noble group VIII metal, a zeolite Y and alumina.

An even more preferred catalyst comprises and preferably consists of nickel, molybdenum, a Y zeolite and alumina.

Another preferred catalyst comprises and preferably consists of nickel, tungsten and alumina or silica alumina.

According to the invention, the method comprises a step f) of hydrotreating the effluent from step e) in admixture with a liquid hydrocarbon feed comprising at least 95% by weight of boiling compounds at a boiling temperature included between 150 and 400 ° C, preferably between 150 and 380 ° C and preferably between 200 and 380 ° C.

All of the effluent from step e) is therefore co-treated in a hydrotreatment step f) in admixture with a liquid hydrocarbon feed separate from said effluent from the second hydrocracking step e).

Said hydrocarbon-based liquid charge can advantageously be a charge originating from a unit external to said process according to the invention or an internal flow to said process according to the invention, said internal flow being different from said effluent from the second hydrocracking step e). Preferably, said liquid hydrocarbon feedstock is a feedstock coming from a unit external to said process according to the invention.

Preferably, said liquid hydrocarbon feedstock treated in step f) in admixture with the effluent from step e) is advantageously chosen from liquid hydrocarbon feedstocks resulting from the direct distillation of a crude oil (or straight run according to Anglo-Saxon terminology) and preferably chosen from straight run diesel, Light Vacuum Gasoil Oil (LVGO) according to Anglo-Saxon terminology or light vacuum distillate, and hydrocarbon liquid fillers from a coking unit (coking according to Anglo-Saxon terminology), preferably coker gas oil, a visbreaking unit (visbreaking according to Anglo-Saxon terminology), a steam cracking unit (steam cracking according to Anglo-Saxon terminology) and / or a catalytic cracking unit (Fluid Catalytic Cracking according to English terminology), preferably LCOs (light cycle oil) or light gas oils from a catalytic cracking unit, and a diesel charge resulting from the conversion of biomass (esterification for example), said charges can be taken alone or as a mixture.

Said hydrocarbon-based liquid charge can also advantageously be a hydrocarbon-based liquid charge originating from a H-Oil type bubbling bed conversion unit.

The proportion of said distinct hydrocarbon liquid charge co-treated with the effluent from step e) in step f) represents between 20% and 80% by weight of the total mass of the total liquid mixture at the inlet of l 'step f) of hydrotreatment, preferably between 30% and 70% by weight and even more preferably between 40% and 60% by weight.

The treatment of the effluent from step e) in admixture with said liquid hydrocarbon feedstock in a hydrotreatment step f), downstream from the hydrocracking step e), also makes it possible to desulfurize said liquid hydrocarbon feedstock , to minimize the formation of heavy polyaromatic products (HPNA). Minimizing the formation of HPNAs makes it possible to minimize the purging required on the liquid fraction, unconverted residue (UCO) resulting from step d) and therefore to increase the overall conversion of the process. The purge rate, corresponding to the ratio between the mass flow rate of the purge flow and the mass flow rate of the hydrocarbon feedstock entering the process according to the invention is advantageously between 0 and 2%.

According to the invention, said step f) operates in the presence of hydrogen and at least one hydrotreatment catalyst, at a temperature between 200 and 390 ° C, under a pressure between 2 and 16 MPa, at a space speed between 0.2 and 5 h -1 and at a quantity of hydrogen introduced such that the volume ratio liter of hydrogen / liter of hydrocarbon is between 100 and 2000 L / L.

Conventional hydrotreatment catalysts can advantageously be used in said step f), which contain at least one amorphous support and at least one hydro-dehydrogenating element chosen from at least one element from non-noble groups VIB and VIII, and preferably at least a group VIB element and at least one non-noble group VIII element.

Preferably, the amorphous support is alumina or silica alumina.

Preferred catalysts are chosen from NiMo or CoMo catalysts on alumina and NiMo or NiW catalysts on alumina silica.

Surprisingly, the hydrotreatment step f) also allows the conversion of the unconverted part of the effluent from the hydrocracking step e), which makes it possible to reduce the amount of catalyst used in the step e) hydrocracking with iso conversion by pass of the stage constituted by the combination of stage e) of hydrocracking and of stage f) of hydrotreatment Furthermore, the presence of the hydrotreatment stage f ) increases the amount of hydrogen in the recycle of the unconverted liquid fraction having a boiling point above 340 ° C (UCO) towards hydrocracking step e), which facilitates their conversion in said step e) and thus further reduces the amount of catalyst required in said step (at iso-lifetime).

The hydrocracking step e) and the hydrotreatment step f) can advantageously be carried out in the same reactor or in different reactors. In the case where they are carried out in the same reactor, an intermediate injection of the hydrocarbon-based liquid charge is advantageously implemented between the different catalytic beds. In this case, the reactor comprises several catalytic beds, the first catalytic beds comprising the hydrocracking catalyst (s) and the following catalytic beds comprising the hydrotreating catalyst (s).

The hydrotreatment stage f) advantageously operates at a pressure higher than the pressure of the effluent from the hydrocracking stage a).

Thus, in a first particular embodiment, at least a portion and preferably all of the effluent from step f) of hydrotreatment can advantageously be recycled in step b) of gas / liquid separation.

This configuration allows the use of a single compressor on the hydrogen recycle loop. Indeed, in this case, the recycle of gas containing hydrogen to step f) is provided by the same compressor as the recycle of gas containing hydrogen to step a).

In a second particular embodiment, at least part and preferably all of the effluent from step f) of hydrotreatment can advantageously be sent to a second gas / liquid separation step to produce a liquid effluent and a gaseous effluent comprising at least hydrogen.

Preferably, said second gas / liquid separation step is implemented in a high pressure high temperature separator operating at a pressure and a temperature compatible with the temperature and the outlet pressure of step f). Said second separation step is preferably carried out at a temperature between 200 and 390 ° C, under a pressure between 2 and 16 MPa.

In this case, the liquid effluent from the second separation step can advantageously be recycled in step e) of hydrocracking and / or in step f) of hydrotreatment.

According to a variant, the gaseous effluent comprising at least hydrogen coming from the second separation step can advantageously be sent to the compression step c). In this case, the process uses two gas / liquid separators and a single compressor on the hydrogen recycle loop, as well as a single make-up hydrogen compressor, which reduces the cost of the installation. .

According to another variant, the gaseous effluent comprising at least hydrogen from the second separation step can be sent in a second compression step before its recycling in step e) and / or in step f) .

Description of the figure

The figure 1 illustrates a particular embodiment of the invention.

The DSV or VGO type hydrocarbon feedstock (1) enters a hydrocracking section A of step a) corresponding to the first hydrocracking step. Said section may include one or two hydrocracking reactors R1 and / or R2 (not shown in the figure). The effluent (2) from step a) is sent to a gas / liquid separator B from step b) making it possible to isolate a gas stream comprising hydrogen (7). The gaseous effluent (7) is sent to a recycle compressor C, it is mixed with a hydrogen make-up stream (11) and then recycled to the hydrocracking reactor via the stream (8).

The liquid effluent (3) from the separator B feeds a fractionation column D of step d).

An effluent comprising light cups (10), a gasoline cup (9), and a middle distillate cup (8) corresponding to diesel and kerosene are separated in the fractionation column. An unconverted liquid fraction cutter called UCO (UnConverted-Oil) (12) is also separated and then sent via the stream (4) to a second hydrocracking section E of step e). Said hydrocracking section E comprises a hydrocracking reactor R3 (not shown in the figure). A purge (13) is carried out on the flow of the unconverted liquid fraction from step d).

A liquid hydrocarbon feedstock (12) of the diesel type is injected downstream of the hydrocracking section of the UCO E of step e) and is treated in a hydrodesulfurization section F of step f) in mixture with the effluent from the hydrocracking section E, ie the hydrocracked UCO (5).

The examples illustrate the invention without limiting its scope.

Examples: Example 1a: comparison: dedicated processes

This example is a comparative base case in which the hydrocracking processes of DSV or VGO and hydrodesulfurization of gas oils (GO) are implemented in two separate dedicated processes.

The hydrocracking unit processes a diesel fuel charge under vacuum (VGO) and the HDS diesel fuel unit processes a diesel fuel charge (GO) described in Table 1: Table 1 Type VGO GO Debit t / h 49 51 Density t / m ³ 0.92 0.83 PI TBP ° C 300 47 PF TBP ° C 552 416 S wt% 2.18 0.68 NOT wtppm 1800 210

Main operating conditions • Diesel hydroprocessing

The GO charge is injected in a preheating step and then into a hydrotreatment reactor under the following conditions set out in Table 2: Table 2 Reactor HDS GO Temperature ° C 336 Partial pressure H ₂ MPa 4 Catalyst CoMo on HR1246 alumina VVH h-1 1.04

The catalyst used is a CoMo catalyst on alumina of the HR1246 type sold by the company Axens.

The diesel HDS process is then composed of a heat recovery train then of high pressure separation including a recycle compressor and allowing to separate on the one hand the hydrogen, the sulfur and nitrogen compounds and on the other share the desulphurized effluent feeding a steam stripper in order to separate the hydrogen sulphide and the naphtha.

The final diesel effluent has the following properties set out in Table 3: Table 3 Type GO Debit t / h 46 Density t / m3 0.82 PI TBP ° C 151 PF TBP ° C 450 S wtppm 10.00 NOT wtppm 2

• Two-stage hydrocracker

The VGO feedstock is injected in a preheating step and then into a hydrotreatment reactor under the following conditions set out in Table 4: Table 4 Reactor R1 Temperature ° C 385 Partial pressure H ₂ MPa 14 Catalyst CoMo on alumina HR1058 VVH h-1 1.67

The catalyst used is a CoMo catalyst on alumina of the HR1058 type sold by the company Axens.

The effluent from this reactor is then mixed with a stream of hydrogen to be cooled and then is injected into a second reactor known as hydrocracking R2 operating under the conditions of table 5: Table 5 Reactor R2 Temperature ° C 390 Partial pressure H ₂ MPa 12.5 Catalyst Metal on HYK742 zeolite VVH h-1 3

The catalyst used is a metal catalyst on zeolite of the HYK742 type sold by the company Axens.

R1 and R2 constitute the first stage of the hydrocracker, the effluent of R2 is then sent in a separation stage composed of a heat recovery train then of high pressure separation including a recycle compressor and making it possible to separate d '' on the one hand hydrogen, hydrogen sulfide and ammonia and on the other hand the effluent feeding a stripper then an atmospheric fractionation column in order to separate flows concentrated in H ₂ S, naphtha, kerosene, diesel a the desired specification, and an unconverted heavy flow. This unconverted heavy stream is injected in a preheating step and then into a hydrocracking reactor R3 constituting the second hydrocracking step. This R3 reactor is operated under the following conditions set out in Table 6: Table 6 Reactor R3 Temperature ° C 345 Partial pressure H ₂ MPa 12.5 Catalyst Metal on amorphous silica-alumina HDK766 VVH h-1 3

The catalyst used is a metal catalyst on amorphous silica-alumina of the HDK766 type sold by the company Axens.

The R3 effluent is then injected into the high pressure separation step downstream from the first hydrocracking step and recycled. The mass flow at the inlet of reactor R3 is equal to the mass flow of the VGO charge, a purge corresponding to 2% by mass of the flow of the VGO charge is taken at the bottom of the fractionation on the flow of unconverted oil.

The distillate cut produced in the hydrocracker and recovered from the fractionation column complies with the Euro V specifications, in particular it has less than 10 ppm by weight of sulfur.

The average distillate yield of this process is 85% by mass, for an overall conversion of 98% by mass of hydrocarbons with a boiling point above 380 ° C.

The total volume of catalyst required for this scheme is 147m ³ .

Example 1b: comparison: co-treatment of a DSV feed and a diesel feed in a two-stage hydrocracking process.

This example is a comparative base case in which the hydrocracking reactions of DSV or VGO and hydrodesulfurization of gas oils (GO) are implemented in a single hydrocracking process two stages (co-treatment of the two feeds)

The hydrocracking unit processes a distillate charge under vacuum (VGO) in admixture with a diesel charge (GO) identical to those used in Example 1a). The characteristics of the loads (VGO) and (GO) are given in table 1.

Main operating conditions

The mixture of the two charges VGO and GO is injected in a preheating step then in a hydrotreatment reactor R1 operating under conditions identical to those used in Table 4 of Example 1a).

The effluent from reactor R1 is then mixed with a stream of hydrogen to be cooled and then is injected into a second so-called hydrocracking reactor R2 operating under conditions identical to those used in Example 1a) and described in table 5:
R1 and R2 constitute the first stage of the hydrocracker, the effluent from the reactor R2 is then sent to a separation stage composed of a heat recovery train then of high pressure separation including a recycle compressor and making it possible to separate on the one hand hydrogen, hydrogen sulfide and ammonia and on the other hand the effluent supplying a stripper then an atmospheric fractionation column in order to separate flows concentrated in H ₂ S, naphtha, kerosene, diesel has the desired specification, and an unconverted heavy flow. This unconverted heavy stream is injected in a preheating step and then into a hydrocracking reactor R3 constituting the second hydrocracking step. This reactor R3 is operated under the same conditions as those used in Example 1a) and are described in Table 6:

The effluent from reactor R3 is then injected into the high pressure separation step downstream from the first hydrocracking step and recycled. The mass flow at the inlet of reactor R3 is equal to the mass flow of the VGO charge, a purge corresponding to 2% by mass of the flow of the VGO charge is taken at the bottom of the fractionation on the flow of unconverted oil.

The distillate cut produced in the hydrocracker and recovered from the fractionation column complies with the Euro V specifications, in particular it has less than 10 ppm by weight of sulfur.

The average distillate yield of this process is 80% by mass, for an overall conversion of 98% by mass of hydrocarbons with a boiling point above 380 ° C.

The total volume of catalyst required for this scheme is 110m ³ .

Example 2: According to the invention

This example is a diagram in accordance with the invention in which the hydrodesulfurization of gas oils takes place in co-processing with the effluent from the second hydrocracking stage (therefore with hydrocracked UCO). This scheme therefore consists of a single two-stage hydrocracker (there is no process dedicated to the hydrodesulfurization of diesel).

The first step of method a) is exactly the same as the first step according to Example 1. R1 and R2 operate on the same pure VGO or DSV charge described in Table 1 under the same operating conditions set out in Tables 4 and 5.

The effluent from reactor R2 is then sent to a separation step b) composed of a heat recovery train and then to high pressure separation including a recycle compressor (step c) and making it possible to separate the hydrogen, hydrogen sulfide and ammonia and on the other hand the effluent supplying a stripper then an atmospheric fractionation column (step d) in order to separate flows concentrated in H ₂ S, naphtha, kerosene, diesel fuel with desired specification, and an unconverted heavy liquid fraction (UCO) having a boiling point above 380 ° C. This unconverted heavy stream is injected in a preheating step and then into a hydrocracking reactor R3 constituting the second hydrocracking step e). This reactor is operated under the following conditions set out in Table 7: Table 7 Reactor R3 Temperature ° C 345 Partial pressure H ₂ MPa 13 Catalyst Metal on amorphous silica-alumina HDK766 VVH h-1 2.8

The catalyst used is a metal catalyst on amorphous silica-alumina of the HDK766 type sold by the company Axens.

The effluent from reactor R3 is then mixed with a GO charge identical to that of Example 1 described in Table 1. This GO charge was previously preheated by means known to those skilled in the art, by thermal integration with a other process flow. The effluent mixture from reactor R3 and the feedstock GO is then injected into a hydrotreatment reactor R4 (step f), the target is the desulfurization of the GO charge. The operating conditions of this reactor are the following set out in Table 8: Table 8 Reactor R4 Temperature ° C 385 Partial pressure H ₂ MPa 12.5 Catalyst NiMo on HR1058 alumina VVH h-1 5.4

The catalyst used is a NiMo catalyst on alumina of the HR1058 type sold by the company Axens.

The effluent from reactor R4 (step f) is then injected into the high pressure separation step b) downstream from the first hydrocracking step a) and recycled. The mass flow at the inlet of reactor R3 is equal to the mass flow of the VGO charge, a purge corresponding to 1% by mass of the flow of the VGO charge is taken at the bottom of the fractionation on the flow of unconverted oil.

The distillate cut produced recovered from the fractionation column complies with the Euro V specification, in particular it has less than 10 ppm by weight of sulfur.

The average distillate yield of this process is 85% by mass, for an overall conversion of 99% by mass of hydrocarbons with a boiling point above 380 ° C.

The total volume of catalyst required for this scheme is 78m ³ .

• réduire l'investissement initial et la consommation de catalyseur dans la deuxième étape e) d'hydrocraquage, ce qui se traduit par une réduction du volume total de catalyseur nécessaire pour l'ensemble du procédé,

et par rapport au co-traitement d'une charge DVS et d'une charge GO dans un procédé d'hydrocraquage deux étapes :

• de limiter le craquage de la charge de type gazole dans l'étape d'hydrotraitement ce qui se traduit par l'augmentation du rendement en distillat moyens,
• en plus de désulfurer la charge de type gazole, de minimiser la formation de produits lourds polyaromatiques (HPNA), ce qui se traduit par la limitation de la purge de la bouche de seconde étape d'hydrocraquage et donc d'augmenter la conversion du procédé, et
• en plus de désulfurer la charge de type gazole, de convertir la partie non convertie issue de la deuxième étape d'hydrocraquage e), ce se traduit par la réduction de la quantité de catalyseur utilisée dans ladite étape e) d'hydrocraquage, à iso conversion par passe de l'étape constituée de la combinaison de la deuxième étape d'hydrocraquage e) et de l'étape f) d'hydrotraitement.

Unexpectedly, the implementation of the reactor R4 of step f) under the stated operating conditions makes it possible, with respect to the dedicated methods of Example 1a) to:

• reduce the initial investment and the consumption of catalyst in the second hydrocracking step e), which results in a reduction in the total volume of catalyst required for the whole process,

and compared to the co-treatment of a DVS charge and a GO charge in a two-stage hydrocracking process:

• limiting the cracking of the diesel-type feedstock in the hydrotreatment step, which results in an increase in the yield of middle distillate,
• in addition to desulfurizing the diesel-type feedstock, minimizing the formation of heavy polyaromatic products (HPNA), which results in limiting the purging of the mouth of the second hydrocracking step and therefore increasing the conversion of the process , and
• in addition to desulphurizing the diesel-type feedstock, converting the unconverted part resulting from the second hydrocracking step e), this results in the reduction of the amount of catalyst used in said hydrocracking step e), to iso conversion by pass of the stage consisting of the combination of the second hydrocracking stage e) and of the hydrotreatment stage f).

Claims (15)

1. Process for hydrocracking hydrocarbon-containing feedstocks containing at least 20% by volume and preferably at least 80% by volume of compounds boiling above 340°C, said process comprising at least the following stages:

   a) Hydrocracking said feedstocks operating, in the presence of hydrogen and at least one hydrocracking catalyst, at a temperature comprised between 250 and 480°C, under a pressure comprised between 2 and 25 MPa, at a space velocity comprised between 0.1 and 6 h-1 and at a quantity of hydrogen introduced such that the volume ratio litre of hydrogen/litre of hydrocarbon is comprised between 100 and 2000 L/L,

   b) Gas/liquid separation of the effluent originating from stage a) in order to produce a liquid effluent and a gaseous effluent comprising at least hydrogen,

   c) Sending the gaseous effluent comprising at least hydrogen into a compression stage before it is recycled into at least the hydrocracking stage a),

   d) Fractionation of the liquid effluent into at least one effluent comprising the converted hydrocarbon-containing products having boiling points less than 340°C and an unconverted liquid fraction having a boiling point greater than 340°C,

   e) Hydrocracking said unconverted liquid fraction originating from stage d) operating, in the presence of hydrogen and a hydrocracking catalyst comprising a hydrogenating function comprising at least one metal from Group VIII selected from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum and/or at least one metal from Group VIB selected from chromium, molybdenum and tungsten, alone or as a mixture, and an acid function selected from silica-alumina and zeolites, at a temperature comprised between 250 and 480°C, under a pressure comprised between 2 and 25 MPa, at a space velocity comprised between 0.1 and 6 h-1 and at a quantity of hydrogen introduced such that the volume ratio litre of hydrogen/litre of hydrocarbon is comprised between 100 and 2000 L/L,

   f) Hydrotreating all of the effluent originating from stage e) in a mixture with a hydrocarbon-containing liquid feedstock comprising at least 95% by weight of compounds boiling at a boiling point comprised between 150 and 400°C, separate from said effluent originating from the second hydrocracking stage e), said hydrotreating stage f) operating in the presence of hydrogen and at least one hydrotreating catalyst comprising at least one amorphous alumina support and at least one hydro-dehydrogenating element selected from at least one non-noble element from Groups VIB and VIII, at a temperature comprised between 200 and 390°C, under a pressure comprised between 2 and 16 MPa, at a space velocity comprised between 0.2 and 5 h-1 and at a quantity of hydrogen introduced such that the volume ratio litre of hydrogen/litre of hydrocarbon is comprised between 100 and 2000 L/L.
2. Process according to Claim 1 in which the hydrocarbon-containing feedstocks treated in said process and sent into stage a) are selected from the hydrocarbon-containing feedstocks containing at least 80% by volume of compounds boiling between 370 and 580°C.
3. Process according to one of Claims 1 or 2 in which the hydrocarbon-containing feedstocks treated in said process and sent into stage a) are selected from the vacuum distillates (VDs) selected from gas oils originating from direct crude distillation or conversion units and distillates originating from desulfurization or hydroconversion of atmospheric residues and/or vacuum residues, deasphalted oils, and feedstocks originating from biomass or even any mixture of the feedstocks mentioned above.
4. Process according to one of Claims 1 to 3 in which the hydrocracking stage a) operates at a temperature comprised between 320 and 450°C, under a pressure comprised between 3 and 20 MPa, at a space velocity comprised between 0.2 and 4 h-1, and at a quantity of hydrogen introduced such that the volume ratio litre of hydrogen/litre of hydrocarbon is comprised between 200 and 2000 L/L.
5. Process according to one of Claims 1 to 4 in which said hydrocarbon-containing feedstocks treated in said process are sent into a hydrotreating stage before being sent into said hydrocracking stage a), said hydrotreating stage operating in the presence of hydrogen and a hydrotreating catalyst and at a temperature comprised between 200 and 400°C, under a pressure comprised between 2 and 16 MPa, at a space velocity comprised between 0.2 and 5 h-1 and at a quantity of hydrogen introduced such that the volume ratio litre of hydrogen/litre of hydrocarbon is comprised between 100 and 2000 L/L.
6. Process according to one of Claims 1 to 5 in which the process comprises a stage d) of fractionation of the liquid effluent originating from stage a) into at least one effluent comprising the converted hydrocarbon-containing products having boiling points less than 380°C and an unconverted liquid fraction having a boiling point greater than 380°C.
7. Process according to one of Claims 1 to 6 in which purging is carried out on the unconverted liquid fraction having a boiling point greater than 340°C.
8. Process according to one of Claims 1 to 7 in which the hydrocracking stage e) operates at a temperature comprised between 320 and 450°C, under a pressure comprised between 3 and 20 MPa, at a space velocity comprised between 0.2 and 4 h-1, and at a quantity of hydrogen introduced such that the volume ratio litre of hydrogen/litre of hydrocarbon is comprised between 200 and 2000 L/L.
9. Process according to one of Claims 1 to 8 in which the hydrocarbon-containing liquid feedstock used in stage e) comprises at least 95% by weight of compounds boiling at a boiling point comprised between 150 and 380°C.
10. Process according to one of Claims 1 to 9 in which said hydrocarbon-containing liquid feedstock treated in stage f) in a mixture with the effluent originating from stage e) is selected from straight run gas oil, light vacuum gas oil (LVGO) or light vacuum distillate, and hydrocarbon-containing liquid feedstocks originating from a coking unit, preferably coker gas oil, from a visbreaking unit, from a steam cracking unit and/or from a fluid catalytic cracking unit, preferably light cycle oils (LCO) or light gas oils originating from a fluid catalytic cracking unit, and a gas oil feedstock originating from biomass conversion.
11. Process according to one of Claims 1 to 10 in which at least a part of the effluent originating from the hydrotreating stage f) is recycled into the gas/liquid separation stage b).
12. Process according to one of Claims 1 to 10 in which at least a part of the total effluent originating from the hydrotreating stage f) is sent into a second gas/liquid separation stage in order to produce a liquid effluent and a gaseous effluent comprising at least hydrogen.
13. Process according to Claim 12 in which the liquid effluent originating from the second separation stage is recycled into the hydrocracking stage e) and/or into the hydrotreating stage f).
14. Process according to one of Claims 12 or 13 in which the gaseous effluent comprising at least hydrogen originating from the second separation stage is sent into the compression stage c).
15. Process according to one of Claims 12 or 13 in which the gaseous effluent comprising at least hydrogen originating from the second separation stage can be sent into a second compression stage before it is recycled in stage e) and/or in stage f).

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