Method for the fixed-bed treatment of a heavy fossil-based feedstock comprising a fraction of plastic pyrolysis oil

Abstract

Method for treating a feedstock comprising a fraction of plastic and / or tyre and / or solid recovered fuel pyrolysis oil and a heavy fraction of hydrocarbons of fossil origin, said fraction of pyrolysis oil constituting less than 50% by weight of said feedstock, said method comprising: a) a hydrodemetallization stage in a fixed-bed reaction section comprising at least two permutable reactors which is fed at least by said feedstock and a gas stream comprising hydrogen, in the presence of a hydrodemetallization catalyst, b) a hydrotreating stage in a reaction section comprising at least one fixed-bed reactor, said section being fed by said effluent resulting from stage a) and optionally a gas stream comprising hydrogen, in the presence of a hydrotreating catalyst, c) a stage of separating the effluent resulting from stage b).

Description

[0001] FIXED BED TREATMENT PROCESS FOR A HEAVY FEED OF FOSSIL ORIGIN COMPRISING A PLASTIC PYROLYSIS OIL FRACTION

[0002] Technical field

[0003] The present invention relates to the field of hydroconversion of feedstocks comprising mainly a heavy fraction of hydrocarbons of fossil origin and a minor fraction of pyrolysis oil from plastics and / or tires and / or solid recovered fuels (SRF), loaded with impurities. The heavy hydrocarbon fraction is a heavy petroleum feedstock of the atmospheric residue and / or vacuum residue type.

[0004] In particular, the present invention relates to a method for treating such a mixed feedstock in a fixed bed in order to produce higher quality, lower boiling point materials, for example for the production of fuels, or chemicals, while allowing the capture of impurities from the pyrolysis oil of plastics and / or tires and / or CSR.

[0005] Prior art

[0006] For several years, we have seen the emergence of processes in the fuel and chemical sectors incorporating products other than traditional petroleum products, for example waste such as plastics or used oils, in addition to or as a substitute for products of fossil origin.

[0007] In particular, plastics from collection and sorting channels can undergo a pyrolysis step to obtain, among other things, pyrolysis oils. These plastic pyrolysis oils are generally burned to generate electricity and / or used as fuel in industrial boilers or district heating.

[0008] Used tires often undergo the same treatment.

[0009] Solid recovered fuels (SRF), also known as refuse derived fuel (RDF), or solid recovered fuels (SRF), are solid non-hazardous waste prepared for energy recovery, whether they come from household and similar waste, waste from economic activities or construction and demolition waste. SRF are generally a mixture of any combustible waste such as used tires, food by-products (fats, animal meal, etc.), viscose and wood waste, light fractions from shredders (e.g. from used vehicles, electrical and electronic equipment (WEEE)), household and commercial waste, residues from the recycling of various types of waste, including certain municipal waste, plastic waste, textiles, wood among others. SRF generally contains plastic waste.SRFs are currently mainly used for energy. They can be used directly as substitutes for fossil fuels in co-incineration plants (coal and lignite thermal power plants, cement plants, lime kilns) or in household waste incineration units, or indirectly in pyrolysis units dedicated to energy recovery: SRF pyrolysis oils are thus generally burned to generate electricity, or even used as fuel in industrial boilers or district heating.

[0010] Pyrolysis oils from plastics and / or tires and / or CSR can also be recovered, possibly via refining processes, to produce fuels, for example gasoline or diesel, and / or chemicals such as olefins for the production of various polymers in the chemical industry.

[0011] However, this route of recovery of pyrolysis oils from plastics and / or tires and / or CSR is confronted with the problems generated by the specific composition of these oils, in particular by the impurities they contain, the composition of these oils being itself linked to the diversity of the components of plastic waste, tires or CSR.

[0012] Indeed, plastic waste, tires or CSR are generally mixtures of several polymers, for example mixtures of polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, polystyrene. In addition, depending on the uses, plastics may contain, in addition to polymers, other compounds, such as plasticizers, pigments, dyes or even residues of polymerization catalysts, as well as other very varied impurities, organic and mineral, coming from the separation operations of sorting centers, an operation whose selectivity cannot be total.Oils from pyrolysis thus generally contain a lot of diolefins and impurities, in particular metals, silicon, or even halogenated compounds, notably chlorine-based compounds, heteroelements such as sulfur, oxygen and nitrogen, insolubles, often at high levels and which may be incompatible with certain refining units.

[0013] The processing of these oils can pose operability problems, including corrosion, coking, catalytic deactivation, and incompatibility problems with the target polymers. The presence of diolefins, for example, very often leads to problems of instability of the pyrolysis oil, characterized by the formation of gums. Gums and insolubles that may be present in the pyrolysis oil can cause clogging problems in the equipment.

[0014] One way to remove these impurities from plastic and / or tire and / or CSR pyrolysis oils is to carry out hydrotreatment in the presence of catalysts.

[0015] Application WO2018 / 055555 proposes, for example, a comprehensive, very general and relatively complex process for recycling plastic waste, ranging from the actual step of pyrolysis of the plastic waste to a steam cracking step which makes it possible to produce highly recoverable products in the petrochemical field such as olefins and aromatic compounds. The process comprises, among other things, a hydrocracking step of the liquid phase resulting directly from the pyrolysis, preferably in a fixed bed.

[0016] Patent applications FR3107530, FR3113060 and FR3113061 describe processes for treating a plastic pyrolysis oil, comprising, among other things, a selective hydrogenation step of the plastic pyrolysis oil and a fixed-bed hydrotreatment of the hydrogenated effluent. The naphtha cut resulting from a water-specific separation of the hydrotreated effluent followed by a fractionation of the separated hydrocarbon stream can be sent to a steam cracker or be used as a fuel base. According to patent applications FR3113060 and FR3113061, the process integrates one or two fixed-bed hydrocracking steps after the hydrotreatment step, to minimize the yield of the heavy cut and maximize the yield of the naphtha cut by transforming the heavy cut at least in part into a naphtha cut by hydrocracking, a cut generally favored for a steam cracking unit.

[0017] Objectives and Summary of the Invention

[0018] The present invention relates to the field of the recovery of heavy loads of fossil origin that are difficult to recover, such as petroleum residues, which generally contain high levels of impurities such as metals, sulfur, nitrogen, Conradson carbon and asphaltenes, to convert them into lighter products that can be recovered as fuels, for example to produce gasoline, diesel or bunker fuel, or raw materials for petrochemicals.

[0019] More particularly, the present invention provides a process for treating a feedstock comprising a heavy fraction of hydrocarbons of fossil origin having an initial boiling point of at least 340°C and a final boiling point of at least 550°C and containing sulfur and nitrogen, and a fraction of pyrolysis oil from plastics and / or tires and / or solid recovered fuels, said pyrolysis oil fraction constituting less than 50% by weight of said feedstock, said process comprising: a) a hydrodemetallization step carried out in a fixed-bed reaction section comprising at least two permutable reactors, said section being fed at least by said feedstock and a gas stream comprising hydrogen, in the presence of at least one hydrodemetallization catalyst, at a temperature between 300 and 500°C, an absolute pressure between 5 MPa and 35 MPa and an hourly volumetric velocity between 0.1 and 5.0 h -1, b) a hydrotreatment step carried out in a reaction section comprising at least one fixed-bed reactor, said section being fed at least with said effluent from step a) and optionally a gaseous flow comprising hydrogen, in the presence of at least one hydrotreatment catalyst, at a temperature between 300 and 500°C, an absolute pressure between 5 MPa and 35 MPa and an hourly volumetric flow rate between 0.1 and 5.0 h- 1 c) a step of separating the effluent from step b) carried out in a separation section leading to a gaseous fraction and at least one liquid product.

[0020] The inventors have demonstrated that, surprisingly, it is possible to incorporate a minor fraction of plastic and / or tire and / or CSR pyrolysis oil, loaded with impurities, into a heavy hydrocarbon feedstock of fossil origin, typically an atmospheric residue or a vacuum residue, traditionally treated in a fixed bed hydroconversion process, thus allowing optimized treatment of the two difficult feedstocks by effectively treating the impurities present and converting the feedstocks into valuable products.

[0021] The present invention thus proposes a process for the hydroconversion of a heavy feedstock of hydrocarbons of fossil origin, in particular of the atmospheric residue and / or vacuum residue type, in a fixed bed, said feedstock including a minor fraction of pyrolysis oil from plastics and / or tires and / or CSR, thus allowing the production of basic fuels and other recoverable hydrocarbons and / or feedstocks suitable for a steam cracker for the production of olefins and / or aromatics.

[0022] The presence of plastic pyrolysis oil allows a significant increase in the yield of the PI-180°C cut while reducing the yields of the heavy cuts. One of the key aspects of the invention lies in the ability of the fixed-bed reactor(s) to at least partially convert the pyrolysis oil into lighter products thanks to the combination of a high temperature and the presence of a catalyst that allows the hydrogenation of unsaturated molecules (olefins or aromatics). The co-treatment of pyrolysis oil thus makes it possible to improve the yield of certain cuts obtained in the hydrotreated effluent, in particular the gasoline cut.

[0023] It was also demonstrated that despite the presence of silicon in the pyrolysis oil, the products resulting from the process according to the invention contain significantly less of it, which indicates that the silicon has been captured by the catalyst(s). Similarly, the chlorine has been substantially entirely captured and / or converted (into HCl). The products resulting from this stage are therefore low in impurities.

[0024] Another advantage of the invention is to limit the increase in temperature between the inlet and the outlet of a fixed bed reactor, induced in particular by the heat released by the hydrogenation of the diolefins or olefins contained in particular in the pyrolysis oil fraction, this heat being partly absorbed by the heavy fraction of hydrocarbons of fossil origin which is treated simultaneously. This results in an optimized process and limits the significant use of effluent recycling and / or gaseous and / or liquid cooling flows.

[0025] Another objective of the present invention is to produce by means of the same process atmospheric distillates (naphtha, kerosene, diesel), vacuum distillates, marine fuels and / or light gases (C1 to C4).

[0026] Alternatively, naphtha, kerosene and diesel bases can be used in refineries to produce automotive and aviation fuels, such as super-fuels, jet fuels and diesel.

[0027] According to another variant, naphtha, kerosene and diesel type bases can be recovered in a steam cracking unit in order to obtain in particular light olefins which can be used as monomers in the manufacture of polymers.

[0028] According to yet another variant, naphtha, kerosene and diesel type bases can be recovered in a fluidized bed catalytic cracking unit (FCC for Fluid Catalytic Cracking according to the Anglo-Saxon terminology) or in a hydrocracking unit.

[0029] Alternatively, the vacuum distillate can be recycled in a hydrocracking unit.

[0030] An advantage of the invention is to propose a process coupling conversion and purification of heavy feedstocks of fossil origin for the production of low-sulfur marine fuels while recovering a co-feedstock of pyrolysis oil. The quality requirements for marine fuels are described in the ISO 8217 standard. The specification concerning sulfur now focuses on SO emissions X(Annex VI of the MARPOL International Maritime Reorganization Convention) and results in a sulfur content recommendation of less than or equal to 0.5% by weight outside Sulfur Emission Control Areas (SECs) in 2020-2025, and less than or equal to 0.1% by weight in SECs. Another very restrictive recommendation is the sediment content after aging according to ISO 10307-2 (also known as IP390), which must be less than or equal to 0.1% by weight. Also, the viscosity of RMG 380 grade bunker fuels must comply with a viscosity limit of less than 380 cST at 50°C.

[0031] The presence of pyrolysis oil as a co-feed in the treatment of a heavy feedstock of fossil origin makes it possible to directly obtain a fuel oil that meets the specifications in terms of sulfur, sediment and viscosity, without the need to add a fluxing agent. Fluxing agents are generally added to lower the viscosity of a bunker fuel oil in order to meet the viscosity specifications. It is in fact the presence of pyrolysis oil, generally lighter in terms of boiling points, which makes it possible to lower the sulfur content and viscosity to achieve the required specifications.The process according to the invention thus makes it possible to directly obtain a bunker fuel oil meeting the required specifications (without the need to add a flux, which is conventionally the case to meet the specifications) while simultaneously presenting the advantage of being able to recover a load that is difficult to recover such as a pyrolysis oil and of increasing the yield of desired distillates.

[0032] According to one or more implementations of the invention, the process according to the invention comprises at least one step aO) of pretreatment of the pyrolysis oil fraction of plastics and / or tires and / or solid recovered fuels, said pretreatment step being carried out upstream of step a) and comprises an adsorption step and / or a filtration step and / or a centrifugation step and / or an electrostatic separation step and / or a step of washing using an aqueous solution and / or a gas stripping step.

[0033] According to one or more implementations of the invention, the pyrolysis oil fraction constitutes between 1% and 45% by weight of said feedstock, preferably between 2% and 30% by weight of said feedstock, preferably between 2% and 25% by weight of said feedstock.

[0034] According to one or more implementations of the invention, the feedstock consists of said pyrolysis oil fraction and said heavy hydrocarbon fraction, said pyrolysis oil fraction constituting between 1% and 45% by weight, preferably between 2% and 30% by weight, more preferably between 2% and 25% by weight of said feedstock and the heavy hydrocarbon fraction constituting between 55% and 99% by weight, preferably between 70% and 98% by weight, more preferably between 75% and 98% by weight of said feedstock.According to one or more implementations of the invention, the heavy hydrocarbon fraction is chosen from the list consisting of an atmospheric residue or a vacuum residue from the atmospheric and / or vacuum distillation of a crude oil or an effluent from a thermal conversion, hydrotreatment, hydrocracking or hydroconversion unit, an aromatic cut extracted from a lubricant production unit, a deasphalted oil from a deasphalting unit, an asphalt from a deasphalting unit, a residual fraction from the direct liquefaction of coal, a vacuum distillate from the direct liquefaction of coal, oil sands or their derivatives, oil shales or their derivatives, source rock oils or their derivatives, taken alone or as a mixture.

[0035] According to one or more implementations of the invention, the heavy hydrocarbon fraction is a vacuum residue and / or an atmospheric residue.

[0036] According to one or more implementations of the invention, the hydrodemetallization catalyst of step a) comprises from 0.5% to 10% by weight of nickel, expressed as nickel oxide NiO relative to the total weight of the catalyst, and from 1% to 30% by weight of molybdenum, expressed as molybdenum oxide MoOa relative to the total weight of the catalyst, on a mineral support chosen from the group consisting of alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals.

[0037] According to one or more implementations of the invention, the hydrotreatment catalyst of step b) comprises from 0.5% to 10% by weight of nickel, expressed as nickel oxide NiO relative to the total weight of the catalyst, and from 1% to 30% by weight of molybdenum, expressed as molybdenum oxide MoOa relative to the total weight of the catalyst, on a mineral support chosen from the group consisting of alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals.

[0038] According to one or more implementations of the invention, said separation section in step c) comprises means for washing by contact with an aqueous solution.

[0039] According to one or more implementations of the invention, separation step c) comprises: c1) a first separation step carried out at a temperature higher than the precipitation temperature of ammonium halides to obtain at least a first gaseous fraction and a liquid effluent, c2) a second separation step, supplied with a first gaseous fraction and at least a portion of the liquid effluent from step c1) and an aqueous solution, said step being carried out at a temperature lower than the precipitation temperature of ammonium halides to obtain at least a second gaseous fraction, an aqueous effluent and a liquid product.

[0040] According to one or more implementations of the invention, the process according to the invention further comprises a step d) of subsequent treatment of at least one liquid product from step c), said step d) comprising at least one step chosen from the list consisting of hydrotreatment, steam cracking, fluidized bed catalytic cracking, hydrocracking, deasphalting, extraction of lubricating oils.

[0041] According to one or more implementations of the invention, in step (a), the pyrolysis oil fraction and the heavy hydrocarbon fraction of the feedstock are premixed before their introduction into one of said permutable reactors.

[0042] According to one or more implementations of the invention, in step (a), the pyrolysis oil fraction of the feedstock is introduced separately from the heavy hydrocarbon fraction into one of said permutable reactors.

[0043] According to one or more implementations of the invention, step (a) comprises a step of preheating said heavy hydrocarbon fraction, preferably at a temperature between 280°C and 450°C, and a step of preheating the pyrolysis oil fraction carried out at a lower temperature than that of said heavy hydrocarbon fraction, before introducing the feedstock into one of said permutable reactors.

[0044] The invention also relates to the product capable of being obtained, and preferably obtained by the process according to the invention.

[0045] Such a product advantageously has a silicon content of less than or equal to 10 ppm by weight, and / or a chlorine element content of less than or equal to 10 ppm by weight relative to the weight of the product.

[0046] Description of the embodiments

[0047] Some definitions are given below for a better understanding of the invention.

[0048] In this description, the term "include" is synonymous with (means the same as) "include" and "contain", and is inclusive or open and does not exclude other elements not mentioned. It is understood that the term "include" includes the exclusive and closed term "consist".

[0049] In the present description, the expression "between ... and ..." means that the limit values ​​of the interval are included in the range of values ​​described, unless otherwise specified. For the purposes of the present invention, the different parameter ranges for a given step, such as pressure ranges and temperature ranges, may be used alone or in combination. For example, for the purposes of the present invention, a range of preferred pressure values ​​may be combined with a range of more preferred temperature values.

[0050] In the present description, particular and / or preferred embodiments of the invention may be described. They may be implemented separately or combined with each other, without limitation of combination when this is technically feasible.

[0051] In the following, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC press, editor-in-chief DR Lide, 81 ème edition, 2000-2001). For example, group VIII (or VIIIB) according to the CAS classification corresponds to the metals of columns 8, 9 and 10 according to the new IIIPAC classification.

[0052] The metal content is measured by X-ray fluorescence.

[0053] The term "treatment process" refers to a process including hydroconversion and hydrotreating reactions.

[0054] The term "hydroconversion" refers to a process whose primary purpose is to reduce the boiling point range of a feedstock, and in which a substantial portion of the feedstock is converted to products with lower boiling point ranges than the original feedstock. Hydroconversion generally involves the fragmentation of larger hydrocarbon molecules into smaller molecular fragments with a lower number of carbon atoms and a higher hydrogen-to-carbon ratio. The reactions involved in hydroconversion reduce the size of hydrocarbon molecules, primarily by cleavage of carbon-carbon bonds, in the presence of hydrogen to saturate the cleaved bonds and aromatic rings.The mechanism by which hydroconversion occurs typically involves the formation of hydrocarbon free radicals during fragmentation primarily by thermal cracking, followed by capping of the free radical termini or fragments with hydrogen in the presence of active catalyst sites. Of course, during a hydroconversion process, other reactions typically associated with hydrotreating may occur, such as, among others, the removal of sulfur or nitrogen from the feedstock, or the saturation of olefins, and as more broadly defined below.

[0055] The term "hydrotreating," commonly referred to as "HDT," refers to a milder operation whose primary purpose is to remove impurities such as sulfur, nitrogen, oxygen, halides, and trace metals from the feedstock, and to saturate olefins and / or stabilize hydrocarbon free radicals by reacting them with hydrogen rather than allowing them to react with themselves. The primary purpose is not to change the boiling point range of the feedstock. Thus, hydrotreatment includes in particular hydrodesulfurization reactions (commonly called "HDS"), hydrodenitrogenation reactions (commonly called "HDN") and hydrodemetalation reactions (commonly called "H DM"), accompanied by hydrogenation reactions, hydrodeoxygenation (commonly called "HDO"), hydrodearomatization, hydrodechlorination, hydroisomerization, hydrodealkylation, hydrocracking, hydrodeasphalting and Conradson carbon reduction.

[0056] In the following text, "pyrolysis oil" means an oil resulting from the pyrolysis of plastics and / or tires and / or CSR, unless otherwise stated. Also for the sake of simplification, the "heavy hydrocarbon fraction" of the feedstock means a heavy hydrocarbon fraction of fossil origin, unless otherwise stated.

[0057] The charge

[0058] According to a key aspect of the invention, the feedstock comprises mainly a heavy fraction of hydrocarbons of fossil origin and a minor fraction of pyrolysis oil from plastics and / or tires and / or CSR.

[0059] According to a preferred embodiment, the feedstock consists of said minor fraction of pyrolysis oil from plastics and / or tires and / or CSR, and a heavy majority fraction of hydrocarbons of fossil origin.

[0060] The process according to the invention is thus specific to the hydroconversion of a mixture of pyrolysis oil from plastics and / or tires and / or low-content CSR and a heavy fraction of hydrocarbons of fossil origin.

[0061] The fraction of pyrolysis oil from plastics and / or tires and / or CSR constitutes less than 50% by weight of the feedstock (total weight of the feedstock), preferably between 1% and 45% by weight of the feedstock, more preferably between 2% and 30% by weight of the feedstock, even more preferably between 2% and 25% by weight of the feedstock, even more preferably between 3% and 20% by weight of the feedstock, and even more preferably between 5% and 20% by weight of the feedstock, or even between 5% and 15% by weight of the feedstock.

[0062] The feedstock may consist of only these two fractions: the pyrolysis oil fraction and the heavy hydrocarbon fraction, the sum of the pyrolysis oil fraction and the heavy hydrocarbon fraction forming 100% by weight of the feedstock. The heavy hydrocarbon fraction may constitute, preferably when the feedstock consists of said heavy hydrocarbon fraction and the pyrolysis oil fraction, between 55% and 99% by weight of the feedstock, preferably between 70% and 98% by weight of the feedstock, more preferably between 75% and 98% by weight of the feedstock, even more preferably between 80% and 97% by weight of the feedstock, and even more preferably between 80% and 95% by weight of the feedstock, or even between 85% and 95% by weight of the feedstock.

[0063] According to the invention, a "plastic pyrolysis oil or tire pyrolysis oil or CSR pyrolysis oil" is an oil, advantageously in liquid form at room temperature, resulting from the pyrolysis of plastics, preferably from plastic waste originating in particular from collection and sorting channels, or from the pyrolysis of used tires or from the pyrolysis of CSR. It comprises in particular a mixture of hydrocarbon compounds, in particular paraffins, olefins (mono- and / or diolefins), naphthenes and aromatics. At least 80% by weight of these hydrocarbon compounds preferably have a boiling point below 700°C, and preferably below 550°C.In particular, depending on the origin of the pyrolysis oil, it may comprise up to 70% by weight of paraffins, up to 90% by weight of naphthenes, up to 90% by weight of olefins and up to 90% by weight of aromatics, it being understood that the sum of paraffins, naphthenes, olefins and aromatics is equal to 100% by weight of the hydrocarbon compounds.

[0064] Pyrolysis oil may contain diolefins. The diolefin content is commonly determined indirectly as the maleic anhydride value (MAV). The method is based on the Diels-Alder addition reaction between conjugated diolefins and maleic anhydride. The method for determining MAV is described in C. Lôpez-Garcia et al., Near Infrared Monitoring of Low Conjugated Diolefins Content in Hydrotreated FCC Gasoline Streams, Oil & Gas Science and Technology - Rev. IFP, Vol. 62 (2007), No. 1, pp. 57-68. MAV is expressed as mg of maleic anhydride reacted with 1 g of sample (mg / g). MAV ranges between 5 and 100 mg / g in pyrolysis oils.

[0065] The density of pyrolysis oil, measured at 15°C according to the ASTM D4052 method, is generally between 0.75 g / cm 3 and 0.99 g / cm 3 , preferably between 0.75 g / cm 3and 0.95 g / cm 3 .

[0066] Pyrolysis oil may include, and most often does include, additionally impurities such as metals, in particular iron, silicon, halogenated compounds, in particular chlorinated compounds. These impurities may be present in the pyrolysis oil at high levels, for example up to 500 ppm by weight or 700 ppm by weight or even 1000 ppm by weight, and even 5000 ppm by weight, of halogenated elements (in particular chlorine but also bromine, fluorine, iodine or astatine) provided by halogenated compounds, and generally between 1 and 1000 ppm by weight or between 1 and 700 ppm by weight or between 1 and 500 ppm by weight of halogenated elements. Pyrolysis oil can contain up to 500 ppm by weight or 700 ppm by weight or even 1000 ppm by weight or even 5000 ppm by weight of chlorine element provided by chlorinated compounds, and generally between 1 and 1000 ppm by weight or between 1 and 700 ppm by weight or even between 1 and 500 ppm by weight of chlorine elements.

[0067] The oil may contain up to 200 ppm by weight, or even 1500 ppm by weight of metallic or semi-metallic elements, and generally between 1 and 200 ppm by weight or between 1 and 1500 ppm by weight of metallic or semi-metallic elements. Alkali metals, alkaline earth metals, transition metals, poor metals and metalloids may be considered as contaminants of a metallic nature, called metals or metallic or semi-metallic elements. In particular, metals or metallic or semi-metallic elements include silicon, iron or both of these elements. Pyrolysis oil may contain, in particular, up to 200 ppm by weight or even 1000 ppm by weight of silicon, and generally between 1 and 200 ppm by weight or between 1 and 1000 ppm by weight or even between 1 and 500 ppm by weight of silicon. Pyrolysis oil can contain up to 50 ppm by weight or 100 ppm by weight of iron, and generally between 1 and 50 ppm by weight or between 1 and 100 ppm by weight of iron.Pyrolysis oil may also include phosphorus, sodium, calcium, potassium, and magnesium.

[0068] The pyrolysis oil may also comprise other impurities such as heteroelements provided in particular by sulfur compounds, oxygenated compounds and / or nitrogen compounds, at contents generally less than 40,000 ppm by weight of heteroelements and preferably less than 15,500 ppm by weight of heteroelements, and generally between 1 and 40,000 ppm by weight or between 1 and 15,500 ppm by weight of heteroelements. The sulfur compounds are generally present in a content of less than 15,000 ppm by weight and preferably less than 10,000 ppm by weight, and generally between 1 and 15,000 ppm by weight or between 1 and 10,000 ppm by weight of sulfur compounds.

[0069] Oxygenated compounds are generally present in a content of less than 15,000 ppm by weight and preferably less than 10,000 ppm by weight, and generally between 1 and 15,000 ppm by weight or between 1 and 10,000 ppm by weight of oxygenated compounds.

[0070] Nitrogen compounds are generally present in a content of less than 10,000 ppm by weight and preferably less than 5,000 ppm by weight, and generally between 1 and 10,000 ppm by weight or between 1 and 5,000 ppm by weight of nitrogen compounds.

[0071] Pyrolysis oil may also include other impurities such as heavy metals such as mercury, arsenic, zinc and lead, for example up to 100 ppb by weight or 200 ppb by weight of mercury or arsenic, and generally between 1 and 200 ppb by weight or between 1 and 100 ppb by weight of heavy metals.

[0072] The process according to the invention is particularly well suited to treating a pyrolysis oil loaded with impurities, in combination with a heavy hydrocarbon feedstock as defined in more detail below. By loaded with impurities, it is meant that the pyrolysis oil has the following properties:

[0073] - an aromatic content of between 0 and 90% by weight, often between 20 and 90% by weight, and which may be between 50 and 90% by weight; or even between 30 and 70% by weight;

[0074] - a chlorine content of between 2 ppm by weight and 5000 ppm by weight, often between 200 ppm by weight and 5000 ppm by weight, and possibly between 500 ppm by weight and 5000 ppm by weight;

[0075] - a content of metallic elements between 0 ppm by weight and 1500 ppm by weight, and which may be between 1 ppm by weight and 1100 ppm by weight;

[0076] - with an iron element content of between 0 and 100 ppm by weight, often between 5 ppm by weight and 100 ppm by weight, and which may be between 10 ppm by weight and 100 ppm by weight;

[0077] - and a silicon element content of between 0 and 1000 ppm by weight, often between 20 ppm by weight and 1000 ppm by weight, or even between 30 ppm by weight or 40 ppm by weight and 1000 ppm by weight, and which may also be between 100 ppm by weight and 1000 ppm by weight.

[0078] The pyrolysis oil from plastics and / or tires and / or CSR can come from a thermal or catalytic pyrolysis treatment or can be prepared by hydropyrolysis (pyrolysis in the presence of a catalyst and hydrogen).

[0079] The heavy hydrocarbon fraction of fossil origin of the feedstock of the process according to the invention is a heavy hydrocarbon fraction having an initial boiling point of at least 340°C and a final boiling point of at least 550°C and containing sulfur and nitrogen. Preferably, its initial boiling point is at least 350°C, preferably at least 375°C, and its final boiling point is at least 550°C, preferably at least 560°C, and even more preferably at least 600°C.

[0080] The heavy hydrocarbon fraction of the feedstock may comprise, or consist of, atmospheric residues and / or vacuum residues from the atmospheric and / or vacuum distillation of a crude oil. The heavy hydrocarbon fraction of the feedstock may also consist of atmospheric and / or vacuum residues from the atmospheric and / or vacuum distillation of effluents from thermal conversion, hydrotreatment, hydrocracking and / or hydroconversion units.

[0081] The heavy hydrocarbon fraction of the feedstock can also consist of aromatic cuts extracted from a lubricant production unit, deasphalted oils from a deasphalting unit (raffinates from the deasphalting unit), asphalts from a deasphalting unit (residues from the deasphalting unit).

[0082] The heavy hydrocarbon fraction of the feedstock may also be a residual fraction from the direct liquefaction of coal (an atmospheric residue and / or a vacuum residue from, for example, the H-Coal® process).

[0083] All these fractions of fossil origin can be used to constitute the heavy hydrocarbon fraction of the charge treated according to the invention, alone or in a mixture.

[0084] According to one or more implementations, the heavy hydrocarbon fraction comprises, and may consist of, at least one of the following feedstocks, alone or in a mixture: an atmospheric residue or a vacuum residue from the atmospheric and / or vacuum distillation of a crude oil or an effluent from a thermal conversion, hydrotreatment, hydrocracking or hydroconversion unit, an aromatic cut extracted from a lubricant production unit, a deasphalted oil from a deasphalting unit, an asphalt from a deasphalting unit, a residual fraction from the direct liquefaction of coal.

[0085] In the present invention, the heavy hydrocarbon fraction being treated is preferably an atmospheric residue or a vacuum residue, or a mixture of these residues.

[0086] The heavy hydrocarbon fraction of the feedstock treated according to the invention contains impurities, such as sulfur and nitrogen. It may also contain impurities such as metals, Conradson carbon and asphaltenes, in particular C? asphaltenes which are insoluble in heptane.

[0087] The sulfur content may be greater than or equal to 0.1% by weight, or even greater than or equal to 0.5% or 1% by weight, and may be greater than or equal to 2% by weight.

[0088] The nitrogen content is usually between 1 ppm and 8000 ppm by weight, more generally between 200 ppm and 8000 ppm by weight, for example between 2000 ppm and 8000 ppm by weight. The metal contents (in particular Ni and V) may be greater than or equal to 20 ppm by weight, preferably greater than or equal to 100 ppm by weight.

[0089] The Conradson carbon content may be greater than or equal to 3% by weight, or at least 5% by weight. The Conradson carbon content is defined by ASTM D482 and represents for those skilled in the art a well-known assessment of the amount of carbon residue produced after pyrolysis under standard conditions of temperature and pressure.

[0090] The C? asphaltenes content (heptane-insoluble compounds according to ASTM D6560, also corresponding to NF T60-115) can be at least 1% by weight and is often greater than or equal to 3% by weight (with the exception of a heavy hydrocarbon fraction comprising essentially deasphalted oil). C? asphaltenes are compounds known to inhibit the conversion of residual cuts, both by their ability to form heavy hydrocarbon residues, commonly called coke, and by their tendency to produce sediments which severely limit the operability of hydrotreatment and hydroconversion units.

[0091] These contents of sulfur, nitrogen, metals, Conradson carbon and asphaltenes of the heavy hydrocarbon fraction are expressed in % by weight of the total weight of the heavy hydrocarbon fraction of the feedstock.

[0092] According to one or more implementations, the feedstock of the process according to the invention may further comprise, at a low content, typically between 1% and 20% by weight of the feedstock, or even between 1% and 10%, a fraction of vegetable and / or animal oil or fat, and / or a hydrocarbon fraction resulting from thermal and / or catalytic conversion processes of lignocellulosic biomass, such as an oil produced from lignocellulosic biomass, according to various liquefaction methods such as hydrothermal liquefaction or pyrolysis, which is then co-treated with the pyrolysis oil from plastics and / or tires and / or CSR and the heavy fraction of hydrocarbons of fossil origin.

[0093] Oils / fats of vegetable and / or animal origin contain triglycerides and / or free fatty acids and / or esters. Vegetable oils can advantageously be crude or refined, totally or partially, and can be derived from the following plants: rapeseed, sunflower, soybean, palm, palm kernel, olive, coconut, jatropha (purjay), castor oil, cotton, peanuts, flax, crambe, this list not being exhaustive. Algal or fish oils are also relevant. Oils / fats of vegetable and / or animal origin can be used, for example used cooking oils. Animal fats can be chosen from lard or fats composed of residues from the food industry or from the catering industries.

[0094] The term "lignocellulosic biomass" means compounds derived from plants or their by-products, and includes constituents selected from the group consisting of cellulose, hemicellulose (carbohydrate polymers) and / or lignin (aromatic polymer).

[0095] According to one or more implementations, the feedstock of the process according to the invention does not comprise a fraction of vegetable and / or animal oil or fat, or a hydrocarbon fraction resulting from thermal and / or catalytic conversion processes of lignocellulosic biomass such as biomass pyrolysis oil.

[0096] (aO) Pyrolysis oil pretreatment step (optional)

[0097] The pyrolysis oil from plastics and / or tires and / or CSR may advantageously be pretreated in at least one optional pretreatment step aO), prior to step a) of hydrodemetallization, to obtain a pretreated pyrolysis oil which feeds step a).

[0098] According to a variant, this optional pretreatment step aO) makes it possible to reduce the quantity of contaminants and solid particles, in particular the quantity of iron and / or silicon and / or chlorine, possibly present in the pyrolysis oil. This optional step aO) makes it possible in particular to eliminate sediments which may form due to the unstable nature of the pyrolysis oils and / or a compatibility problem between two different feedstocks. Thus, an optional step aO) of pretreatment of the pyrolysis oil is advantageously carried out in particular when said oil comprises more than 10 ppm by weight, in particular more than 20 ppm by weight, more particularly more than 50 ppm by weight of metallic elements and / or solid particles, and in particular when said oil comprises more than 5 ppm by weight of silicon, more particularly more than 10 ppm by weight, or even more than 20 ppm by weight of silicon.Likewise, an optional step aO) of pretreatment of the pyrolysis oil is advantageously carried out in particular when said oil comprises more than 10 ppm by weight, in particular more than 20 ppm by weight, more particularly more than 50 ppm by weight of chlorine.

[0099] Said optional pretreatment step aO) may be carried out by any method known to those skilled in the art for reducing the quantity of contaminants. It may in particular comprise an adsorption step and / or a filtration step and / or a centrifugation step and / or an electrostatic separation step and / or a step of washing using an aqueous solution and / or a gas stripping step. The optional pretreatment step aO) is advantageously carried out at a temperature between 20 and 400°C, preferably between 40 and 350°C, and at a pressure between 0.15 and 10.0 MPa abs, preferably between 0.2 and 7.0 MPa abs.

[0100] According to a variant, said optional pretreatment step aO) is implemented in an adsorption section operated in the presence of at least one adsorbent. The adsorbent may be chosen from a zeolite, activated carbon, a clay, a silica or an alumina.

[0101] Advantageously, said adsorbent comprises less than 1% by weight of metallic elements, preferably is free of metallic elements. By metallic elements of the adsorbent are meant the elements of groups 6 to 10 of the periodic table of elements (new IIIPAC classification). The residence time of the load in the adsorption section is generally between 1 minute and 180 minutes.

[0102] Said adsorption section of the optional step aO) comprises at least one adsorption column, preferably comprises at least two adsorption columns, preferably between two and four adsorption columns, containing said adsorbent. When the adsorption section comprises two adsorption columns, an operating mode may be a so-called "swing" operation, according to the established English term, in which one of the columns is online, i.e. in operation, while the other column is in reserve. When the absorbent of the online column is used up, this column is isolated while the column in reserve is put online, i.e. in operation. The used absorbent can then be regenerated in situ and / or replaced with fresh absorbent so that the column containing it can be put back online once the other column has been isolated.

[0103] Another operating mode is to have at least two columns operating in series. When the absorbent in the column placed at the head is worn out, this first column is isolated and the worn absorbent is either regenerated in situ or replaced with fresh absorbent. The column is then put back online in the last position and so on. This operation is called permutable mode, or according to the English term "PRS" for Permutable Reactor System or "lead and lag" according to the English term "lead and lag". The association of at least two adsorption columns makes it possible to overcome the possible and possibly rapid poisoning and / or clogging of the adsorbent under the combined action of metallic contaminants, diolefins, gums from diolefins and insolubles possibly present in the pyrolysis oil to be treated.The presence of at least two adsorption columns facilitates the replacement and / or regeneration of the adsorbent, advantageously without stopping the pretreatment unit, or even the process, thus reducing the risk of clogging and therefore avoiding stopping the unit due to clogging, controlling costs and limiting adsorbent consumption.

[0104] According to another variant, said optional pretreatment step aO) is implemented in a washing section with an aqueous solution, for example water or an acidic or basic solution. This washing section may comprise equipment for bringing the feedstock into contact with the aqueous solution and separating the phases so as to obtain the pretreated feedstock on the one hand and the aqueous solution comprising impurities on the other hand. Among this equipment, there may be for example a stirred reactor, a decanter, a mixer-decanter and / or a co- or counter-current washing column.

[0105] According to another variant, said optional pretreatment step aO) is implemented by filtration. The filtration step makes it possible to remove inorganic solids, sediments and / or fines contained in the oil, in particular metals, metal oxides and metal chlorides. A filter is generally used whose pore size (for example the diameter or equivalent diameter) is less than 25 μm, preferably less than or equal to 10 μm, even more preferably less than or equal to 5 μm. According to another variant, a filter may be used whose pore size is less than 25 μm but greater than 5 μm. A series of filters with different pore sizes may also be used, in particular a series of filters having decreasing pore sizes in the direction of oil circulation. These filter media are well known for industrial uses.Cartridge filters and self-cleaning filters are suitable, for example. The solids content can be measured, for example, using the Heptane Insolubles test, ASTM Method D-3279. The heptane insolubles content should be reduced to less than 0.5% by weight, preferably less than 0.1%.

[0106] According to a particular embodiment, the pretreatment step aO) by filtration comprises at least one filter whose pore size is less than 10 pm, and preferably greater than 5 pm, optionally followed by a filtration system whose pore size is less than 2 pm and preferably less than 1 pm.

[0107] According to another particular embodiment, the pretreatment step aO) by filtration comprises at least one filter whose pore size is less than 10 pm, and preferably greater than 5 pm, followed by an electrostatic precipitation system.

[0108] According to another particular embodiment, the pretreatment step aO) by filtration comprises at least one filter whose pore size is less than 10 μm, and preferably greater than 5 μm, followed by a system of filter(s) using filtration aids such as sand or diatomaceous earth. According to another variant, said optional pretreatment step aO) is implemented by centrifugation. According to another variant, the pretreatment step aO) comprises centrifugation and filtration.

[0109] According to another variant, said optional pretreatment step aO) is carried out by gas stripping, thereby reducing the oxygen content in the oil. The gas stripping may remove oxygen (O2) that may be dissolved in the feedstock thereby reducing the likelihood of free radical formation leading to polymerization in downstream steps. The method generally involves contacting the oil with a stripping gas (e.g. H2, N2 or a mixture thereof), thereby transferring at least some of the dissolved oxygen from the oil to the stripping gas, followed by separating the stripping gas from the oil. The volume of stripping gas relative to the volume of oil (both volumes measured under gas stripping conditions) is generally greater than 1, and preferably at least 3. In particular embodiments, the stripping gas may contain at least 60% (molar percentage) H2.Any dissolved H2 remaining in the feedstock after the gas stripping step is not a problem, given the downstream hydrodemetallization / hydrotreatment. Preferably, the gas stripping step is completed before any (pre)heating of the feedstock, to minimize potential fouling.

[0110] Said optional pretreatment step aO) generally comprises one or more, preferably several treatments described above. It may in particular comprise a sequence of a washing step using an aqueous solution and / or an adsorption step, followed by a gas stripping step, followed by a filtration step and / or a centrifugation step. All these steps are preferably carried out before any (pre)heating of the load.

[0111] Said optional pretreatment step aO) thus makes it possible to obtain a pretreated pyrolysis oil which then feeds the hydrodemetallization step a).

[0112] (a) Hydrodemetallation step in permutable reactors

[0113] According to the invention, the process comprises a step a) of hydrodemetallization carried out in a fixed-bed reaction section comprising at least two permutable reactors, said section being fed at least by said feedstock comprising mainly said heavy fraction of hydrocarbons of fossil origin and a minor fraction of pyrolysis oil, optionally pretreated in step a0), and a gas stream comprising hydrogen, in the presence of at least one hydrodemetallization catalyst, at a temperature between 300 and 500°C, an absolute pressure between 5 MPa and 35 MPa and an hourly volumetric velocity between 0.1 and 5.0 h' 1 The pyrolysis oil fractions and heavy hydrocarbon fractions can be introduced in different ways into the hydrodemetallation stage.

[0114] According to a first variant, the pyrolysis oil fraction can be premixed with the heavy hydrocarbon fraction of the feedstock before entering the reaction section of hydrodemetallization step a).

[0115] Another variant is the separate injection of the pyrolysis oil fraction and the heavy hydrocarbon fraction into the reaction section of step a). This injection method may be preferred to avoid any problem that would be linked to a chemical incompatibility between the two fractions (risk of demixing or precipitation of asphaltenes for example), or to avoid possible accelerated fouling of the preheating furnace (the high diolefin and olefin contents of the pyrolysis oil from plastics and / or tires and / or CSR can lead to the formation of gums).

[0116] According to these two alternative embodiments, whether or not the fractions are mixed before their introduction into the reaction section of step a) of hydrodemetallization, the feedstock, and in particular the heavy hydrocarbon fraction of the feedstock, is generally preheated to a temperature suitable for hydrodemetallization.

[0117] The preheating of the heavy hydrocarbon fraction is preferably carried out at a temperature between 280°C and 450°C, even more preferably between 300°C and 400°C, and even more preferably between 320°C and 365°C.

[0118] This preheating may also comprise heating the pyrolysis oil fraction, in particular if said fraction is injected separately from the heavy hydrocarbon fraction, however preferably at a lower temperature than for the heavy hydrocarbon fraction so as to limit the formation of gums and / or coking of the preheating equipment (for example furnaces and / or heat exchangers) due to the presence of olefins and diolefins in the pyrolysis oil fraction. Advantageously, the pyrolysis oil fraction may be preheated to a temperature between room temperature, e.g. 15°C, and 350°C, preferably between 100°C and 350°C, more preferably between 100°C and 250°C, even more preferably between 100°C and less than 230°C, or even between 100°C and less than 200°C.The pyrolysis oil fraction may for example be preheated by a furnace or by mixing with a hotter gas stream comprising hydrogen from the hydrogen supplement and / or recycled from step c) of the process according to the invention.

[0119] In the case of a mixture of the two fractions, the preheating can be carried out after the mixing, before or during. In this case, the preheating of the mixture of the two fractions is preferably carried out at a temperature between 280°C and 450°C, even more preferably between 300°C and 400°C, and even more preferably between 320°C and 365°C.

[0120] According to another embodiment where the heavy hydrocarbon and pyrolysis oil fractions are mixed, the pyrolysis oil fraction is heated indirectly by mixing with the heavy hydrocarbon fraction (i.e. heat exchange between the two fractions by bringing said two fractions which have different temperatures into contact).

[0121] Any means known to a person skilled in the art capable of preheating said charge may be used. At least one furnace, commonly called a preheating furnace, may be used, comprising for example at least one heating compartment, and / or tubes into which the charge flows, a mixer of the charge with H2, any type of suitable heat exchangers, for example tubular or spiral heat exchangers into which the charge flows, etc.

[0122] Before its introduction into the reaction section of hydrodemetallization step a), the feedstock undergoes a pressurization step to be adapted to the pressure operated in the reaction section of hydrodemetallization step a), for example using a suitable pump. This pressurization step is preferably carried out before the preheating step.

[0123] The objective of this hydrodemetallization step a) is to reduce the content of impurities, in particular metals, in particular silicon, and halogen (in particular chlorine), and the content of diolefins and olefins which may come from the heavy fossil fraction or from the pyrolysis oil, and thus to protect the downstream hydrotreatment step b) from deactivation and clogging, hence the concept of guard reactors.

[0124] These hydrodemetallization guard reactors are implemented as permutable reactors (“PRS” technology, for “Permutable Reactor System” in English terminology) as described in patent FR2681871.

[0125] Switchable reactors are defined as a set of at least two reactors, one of which can be shut down, generally for regeneration or catalyst replacement or for maintenance, while the other (or others) is (are) in operation.

[0126] These swappable reactors are fixed beds located upstream of the fixed bed hydrotreatment section of step b) and equipped with lines and valves so as to be swapped between them, i.e. for a system with two swappable reactors Ra and Rb, Ra can be upstream of Rb and vice versa. Each reactor Ra, Rb can be taken offline so as to change the catalyst without stopping the rest of the unit. This catalyst change (rinsing, unloading, reloading, sulfurization) is generally enabled by a conditioning section (set of equipment outside the main high pressure loop). The reactor containing the fresh catalyst is then put back online in last position and so on. The swap for catalyst change occurs when the catalyst is no longer sufficiently active (metal poisoning and coking) and / or when clogging results in too high a pressure drop.

[0127] Alternatively, there may be more than 2 swappable reactors in the hydrodemetallization section into swappable reactors.

[0128] During step a) of hydrodemetallation, hydrodemetallation reactions (commonly called HDM) occur, but also hydrodesulfurization reactions (commonly called H DS), hydrodenitrogenation reactions (commonly called HDN) accompanied by hydrogenation, hydrodechlorination, hydrodeoxygenation, hydrodearomatization, hydroisomerization, hydrodealkylation, hydrocracking, hydrodeasphalting and Conradson carbon reduction. Step a) is called hydrodemetallation because it removes the majority of metals from the feed.

[0129] In addition, the silicon contained in the feedstock is deposited on the catalyst(s) during this step. The same applies to chlorinated compounds, a minor part of which (the mineral part) is deposited on the catalyst, while organic chlorinated compounds are transformed into HCl.

[0130] Step a) of hydrodemetallization in permutable reactors according to the invention can advantageously be carried out at a temperature of between 300°C and 500°C, preferably between 350°C and 430°C, and under an absolute pressure of between 5 MPa and 35 MPa, preferably between 11 MPa and 26 MPa, preferably between 14 MPa and 20 MPa. The temperature is usually adjusted according to the desired level of hydrodemetallization and the duration of the treatment aimed for. The temperature is generally adjusted in order to eliminate the majority and preferably all of the metals, including silicon.Most often, the space velocity of the hydrocarbon feedstock, also called liquid hourly space velocity (LHSV) or hourly space velocity (HSV) in English, commonly called WH, and which is defined as the volumetric flow rate of the feedstock divided by the total volume of the catalyst, can be included in a range from 0.1 h. -1 at 5 a.m. -1 , preferably 0.15 h -1 at 3 a.m. -1 , and more preferably 0.2 h -1 at 2 a.m. -1 The amount of hydrogen mixed with the charge can be between 100 and 5000 normal cubic meters (Nm 3 ) per cubic meter (m 3 ) of liquid charge, preferably between 200 Nm 3 / m 3 and 2000 Nm 3 / m 3 , and more preferably between 300 Nm 3 / m 3 and 1000 Nm 3 / m 3 .

[0131] Step a) of hydrodemetallization in permutable reactors is carried out industrially in at least two fixed-bed reactors and preferably with a liquid downflow. Each permutable reactor is a fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrodemetallization catalyst.

[0132] According to one implementation of the invention, at least one reactor of the hydrodemetallization step a) or of the hydrotreatment step b), and preferably all the reactors, is (are) equipped with a filtration and distribution device, for example a device such as those described in patent applications FR3043339 and FR3051375.

[0133] According to one implementation of the invention, step a) and / or step b) may use, upstream of the hydrodemetallization or hydrotreatment catalyst(s), at least one guard bed containing adsorbents of the alumina, silica, silica-alumina, zeolite and / or activated carbon type, possibly containing metals from group VI B and / or VIII. It is also possible to use a series of guard beds with particles of different diameters, in particular a series of guard beds having decreasing diameters in the direction of circulation of the feedstock (also called "grading" according to English terminology).

[0134] The hydrodemetallization catalysts used are preferably known catalysts. They may be granular catalysts comprising, on a support, at least one metal or metal compound having a hydro-dehydrogenating function. These catalysts may advantageously be catalysts comprising at least one metal from group VIII, generally chosen from the group consisting of nickel and cobalt, and / or at least one metal from group VI B, preferably molybdenum and / or tungsten. For example, a catalyst may be used comprising from 0.5% to 10% by weight of nickel, preferably from 1% to 5% by weight of nickel (expressed as nickel oxide NiO), and from 1% to 30% by weight of molybdenum, preferably from 3% to 20% by weight of molybdenum (expressed as molybdenum oxide MoOa) relative to the weight of the catalyst on a mineral support.The total content of metal oxides from groups VI B and VIII may be from 5% to 40% by weight, preferably from 5% to 30% by weight, relative to the weight of the catalyst, and the weight ratio expressed as metal oxide between metal (or metals) from group VI B and metal (or metals) from group VIII is generally between 20 and 1, and most often between 10 and 2. The support may for example be chosen from the group consisting of alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals. Advantageously, this support may contain other doping compounds, in particular oxides chosen from the group consisting of boron oxide, zirconia, ceria, titanium oxide, phosphoric anhydride and a mixture of these oxides. Most often an alumina support is used and very often an alumina support doped with phosphorus and possibly boron.When phosphoric anhydride P2Os is present, its concentration is less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% by weight relative to the total weight of the alumina. When boron trioxide B2Os is present, its concentration is less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% relative to the total weight of the alumina. The alumina used may be a y (gamma) or q (eta) alumina. Said hydrodemetallization catalyst is for example in the form of extrudates.

[0135] Catalysts that can be used in step a) of hydrodemetallation in permutable reactors are, for example, indicated in patent documents EP 0113297, EP 0113284, US 5221656, US 5827421, US 7119045, US 5622616 and US 5089463.

[0136] Said hydrodemetallization step a) makes it possible to obtain a hydrodemetallized effluent, i.e. with a reduced content of metals, including silicon, chlorine and with a reduced content of olefins, in particular diolefins. Preferably, at least 50%, and more preferably at least 75% of the chlorine, silicon, metals and diolefins of the initial feed are respectively removed during step a).

[0137] At the end of step a) of hydrodemetallization, the content of metals Ni and V is generally less than 20 ppm by weight, and preferably less than 10 ppm by weight relative to the weight of effluent.

[0138] At the end of hydrodemetallization step a), the silicon content is generally less than 10 ppm by weight, and preferably less than 5 ppm by weight, preferably less than or equal to 2 ppm by weight, or even less than or equal to 1 ppm by weight relative to the weight of the effluent.

[0139] At the end of step a) of hydrodemetallization, the chlorine content is generally less than 10 ppm by weight, and preferably less than 5 ppm by weight, preferably less than or equal to 2 ppm by weight, or even less than or equal to 1 ppm by weight relative to the weight of effluent.

[0140] At the end of step a) of hydrodemetallation, the diolefin content, expressed in MAV value as defined above, is generally less than 5 mg / g, preferably less than 1 mg / g.

[0141] The effluent obtained at the end of hydrodemetallization step a) is sent, preferably directly, to hydrotreatment step b). (b) Hydrotreatment step

[0142] According to the invention, the treatment method comprises a hydrotreatment step b) carried out in a reaction section comprising at least one fixed-bed reactor, said section being supplied at least with said effluent from step a) and optionally a gas stream comprising hydrogen, in the presence of at least one hydrotreatment catalyst, at a temperature between 300 and 500°C, an absolute pressure between 5 MPa and 35 MPa and an hourly volumetric velocity between 0.1 and 5.0 h -1 .

[0143] Hydrotreatment step b) includes hydrotreatment reactions, but also hydroconversion reactions as defined above in the “definition” section.

[0144] In hydrotreatment step b), the conversion rate is moderate or even low, generally less than 45%, most often less than 35% at the end of the cycle, and less than 25% at the beginning of the cycle. The conversion rate generally varies during the cycle due to the increase in temperature to compensate for catalytic deactivation. The conversion rate is defined as the mass fraction of organic compounds having a boiling point above 520°C in the feed at the inlet of the reaction section minus the mass fraction of organic compounds having a boiling point above 520°C at the outlet of the reaction section in the effluent, all divided by the mass fraction of organic compounds having a boiling point above 520°C at the inlet of the reaction section in the feed.

[0145] According to a preferred variant, the hydrotreatment step b) comprises a first hydrodemetallization step b1) (HDM) carried out in one or more fixed-bed hydrodemetallization zones and a second subsequent hydrodesulfurization step b2) (H DS) carried out in one or more fixed-bed hydrodesulfurization zones. During said first hydrodemetallization step b1), the effluent from step a) is brought into contact with a hydrodemetallization catalyst, under hydrodemetallization conditions, then during said second hydrodesulfurization step b2), the effluent from the first hydrodemetallization step b1) is brought into contact with a hydrodesulfurization catalyst, under hydrodesulfurization conditions. This process, known as HYVAHL-F™, is for example described in US patent 5417846.

[0146] The person skilled in the art will readily understand that, in hydrodemetallization step b1), hydrodemetallization reactions are carried out, but in parallel also a part of the other hydrotreatment reactions, and in particular hydrodesulfurization and hydrocracking. Similarly, in hydrodesulfurization step b2), hydrodesulfurization reactions are carried out, but in parallel also a part of the other hydrotreatment reactions, and in particular hydrodemetallization and hydrocracking.

[0147] A person skilled in the art sometimes defines a transition zone in which all types of hydrotreatment reactions occur. According to another variant, the hydrotreatment step b) comprises a first hydrodemetallization step b1) carried out in one or more fixed-bed hydrodemetallization zones, a second subsequent transition step b2) carried out in one or more fixed-bed transition zones, and a third subsequent hydrodesulfurization step b3) carried out in one or more fixed-bed hydrodesulfurization zones.During said first hydrodemetallization step b1), the effluent from step a) is brought into contact with a hydrodemetallization catalyst, under hydrodemetallization conditions, then during said second transition step b2), the effluent from the first hydrodemetallization step b1) is brought into contact with a transition catalyst, under transition conditions, then during said third hydrodesulfurization step b3), the effluent from the second transition step b2) is brought into contact with a hydrodesulfurization catalyst, under hydrodesulfurization conditions.

[0148] The need for a hydrodemetallization step b1) according to the above variants in addition to step a) of hydrodemetallization in permutable guard reactors is justified when the hydrodemetallization carried out during step a) is not sufficient to protect the catalysts of step b), in particular the hydrodesulfurization catalysts.

[0149] Each fixed bed reactor comprises n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrotreatment catalyst.

[0150] The hydrotreatment step b) according to the invention is carried out under hydrotreatment conditions. It can advantageously be carried out at a temperature of between 300°C and 500°C, preferably between 350°C and 430°C and under an absolute pressure of between 5 MPa and 35 MPa, preferably between 11 MPa and 26 MPa, more preferably between 14 MPa and 20 MPa. The temperature is usually adjusted according to the desired level of hydrotreatment and the duration of the treatment. Most often, the space velocity of the feed, also called liquid hourly space velocity (LHSV) or hourly space velocity (HSV) according to English terminology, commonly called WH, and which is defined as the volumetric flow rate of the feed divided by the total volume of the catalyst, can be in a range from 0.1 h -1 at 5 a.m. -1 , preferably 0.1 h -1 at 2 a.m. -1, and more preferably 0.1 h -1 at 1 a.m. 1 The amount of hydrogen mixed with the charge can be between 100 and 5000 normal cubic meters (Nm 3 ) per cubic meter (m 3 ) of liquid charge, preferably between 200 Nm 3 / m 3 and 2000 Nm 3 / m 3 , and more preferably between 300 Nm 3 / m 3 and 1500 Nm 3 / m 3 . Hydrotreatment step b) can be carried out industrially in one or more liquid downflow reactors.

[0151] The hydrotreatment catalysts used are preferably known catalysts. They may be granular catalysts comprising, on a support, at least one metal or metal compound having a hydro-dehydrogenating function. These catalysts may advantageously be catalysts comprising at least one metal from group VIII, generally chosen from the group consisting of nickel and cobalt, and / or at least one metal from group VI B, preferably molybdenum and / or tungsten. For example, a catalyst may be used comprising from 0.5% to 10% by weight of nickel, preferably from 1% to 5% by weight of nickel (expressed as nickel oxide NiO), and from 1% to 30% by weight of molybdenum, preferably from 3% to 20% by weight of molybdenum (expressed as molybdenum oxide MoOa) relative to the weight of the catalyst, on a mineral support.This support can for example be chosen from the group consisting of alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals.

[0152] Advantageously, this support may contain other doping compounds, in particular oxides chosen from the group consisting of boron oxide, zirconia, ceria, titanium oxide, phosphoric anhydride and a mixture of these oxides. An alumina support is most often used and very often an alumina support doped with phosphorus and possibly boron. When phosphoric anhydride P2O5 is present, its concentration is less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% by weight relative to the total weight of the alumina. When boron trioxide B2O5 is present, its concentration is less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% by weight relative to the total weight of the alumina. The alumina used can be a y (gamma) or q (eta) alumina. This catalyst is most often in the form of extrudates.The total content of metal oxides of groups VI B and VIII can be from 3% to 40% by weight and generally from 5% to 30% by weight relative to the weight of the catalyst, and the weight ratio expressed as metal oxide between metal (or metals) of group VIB and metal (or metals) of group VIII is generally between 20 and 1, and most often between 10 and 2.

[0153] In the case of a hydrotreatment step including a step b1) of hydrodemetallization (HDM) then a step b2) of hydrodesulfurization (HDS), specific catalysts adapted to each step are preferably used. Catalysts that can be used in the hydrodemetallization step b1) are, for example, indicated in patent documents EP 0113297, EP 0113284, US 5221656, US 5827421, US 7119045, US 5622616 and US 5089463. Catalysts that can be used in the hydrodesulfurization step b3) are, for example, indicated in patent documents EP 0113297, EP 0113284, US 6589908, US 4818743 or US 6332976. It is also possible to use a mixed catalyst, also called a transition catalyst, active in hydrodemetallization and hydrodesulfurization, both for the hydrodemetallization section b1) and for the hydrodesulfurization section b2) as described in patent document FR 2940143.

[0154] In the case of a hydrotreatment step including a hydrodemetallization (HDM) step b1) then a transition step b2), then a hydrodesulfurization (HDS) step b3), specific catalysts adapted to each step are preferably used. Catalysts that can be used in the hydrodemetallization step b1) are, for example, indicated in patent documents EP 0113297, EP 0113284, US 5221656, US 5827421, US 7119045, US 5622616 and US 5089463. Catalysts that can be used in the transition step b2), active in hydrodemetallization and hydrodesulfurization, are, for example, described in patent document FR 2940143. Catalysts that can be used in the hydrodesulfurization step b3) are, for example, indicated in patent documents EP 0113297, EP 0113284, US 6589908, US 4818743 or US 6332976. It is also possible to use a transition catalyst as described in the patent document FR 2940143 for sections b1), b2) and b3).

[0155] Hydrotreatment step b) is carried out under conditions which make it possible to obtain a hydrotreated effluent, i.e. with a reduced content of sulphur, nitrogen, asphaltenes and Conradson carbon.

[0156] At the end of hydrotreatment step b), the sulfur content is generally less than 0.5% (5000 ppm) by weight, and preferably less than 0.48% (4800 ppm) by weight relative to the weight of effluent.

[0157] At the end of hydrotreatment step b), the nitrogen content is generally less than 3500 ppm by weight, and preferably less than 3000 ppm by weight relative to the weight of effluent.

[0158] At the end of hydrotreatment step b), the asphaltene content C? is generally less than 2% by weight, and preferably less than 1% by weight relative to the weight of effluent.

[0159] At the end of hydrotreatment step b), the Conradson carbon content is generally less than 8% by weight, and preferably less than 6% by weight relative to the weight of effluent.

[0160] Said effluent from hydrotreatment step b) contains the conversion products, in particular said effluent has a reduced content (relative to the feed) of hydrocarbons having an initial boiling point of at least 340°C, or at least 350°C, 375°C, 450°C, 460°C, 500°C, or 600°C depending on the nature of the feed. (c) Separation step

[0161] According to the invention, the method further comprises a separation step (c), which separates part, or all, of the effluent from step b) in a separation section leading to a gaseous effluent and at least one liquid product.

[0162] This separation step c) separates part or all of said effluent into several fractions including at least one liquid product which may be a light cut (naphtha, diesel, kerosene), intermediate (vacuum distillate) or heavy (vacuum residue).

[0163] Separation step c) is carried out in a separation section which comprises any separation means known to a person skilled in the art. Said separation section may comprise one or more expansion tanks arranged in series, and / or one or more steam and / or hydrogen stripping columns, and / or an atmospheric distillation column, and / or a vacuum distillation column.

[0164] According to one or more embodiments, this separation step c) is carried out by a series of at least two successive expansion tanks.

[0165] According to one or more other embodiments, this separation step c) is carried out by one or more steam and / or hydrogen stripping columns.

[0166] According to one or more preferred embodiments, this separation step c) is carried out by an atmospheric distillation column, and more preferably by an atmospheric distillation column and a vacuum column receiving the atmospheric residue.

[0167] According to the most preferred embodiment(s), this separation step c) is carried out by one or more flash drums, an atmospheric distillation column and a vacuum column receiving the atmospheric residue.

[0168] The gaseous effluent comprises in particular H2, H2S, NH3, and C1-C4 hydrocarbons. This gaseous effluent can be separated from the effluent obtained at the end of step b) using separation devices well known to those skilled in the art, in particular using one or more separator drums which can operate at different pressures and temperatures, possibly associated with a steam or hydrogen stripping means and one or more distillation columns. The effluent obtained at the end of hydrotreatment step b) is advantageously separated in at least one separator drum into at least one gaseous effluent and at least one liquid product. These separators can, for example, be high pressure high temperature (HPHT) separators and / or high pressure low temperature (HPBT) separators.After possible cooling, this gaseous effluent is preferably treated in a hydrogen purification means so as to recover the hydrogen not consumed during the hydrodemetallization and hydrotreatment reactions. The hydrogen purification means may be an amine wash, a membrane, a PSA type system, or several of these means arranged in series. The purified hydrogen may then advantageously be recycled in the process according to the invention, after possible recompression. The hydrogen may be introduced at the inlet of the hydrodemetallization step a) and / or at different locations during the hydrotreatment step b). The hydrogen (hot because it comes out of step c) may also be used to preheat the pyrolysis oil fraction when it is introduced separately from the heavy fraction. The recovered gaseous hydrogen may also be used in other refinery installations.

[0169] Separation step c) may also comprise atmospheric distillation and / or vacuum distillation. Advantageously, separation step c) further comprises at least one atmospheric distillation, in which the liquid effluent obtained after gas / liquid separation is fractionated by atmospheric distillation into at least one atmospheric distillate fraction and at least one atmospheric residue fraction.

[0170] Furthermore, the separation step c) of the process according to the invention may advantageously further comprise at least one vacuum distillation in which the liquid effluent obtained after gas / liquid separation and / or the atmospheric residue fraction obtained after atmospheric distillation is (are) fractionated by vacuum distillation into at least one vacuum distillate fraction and at least one vacuum residue fraction. Preferably, the separation step c) firstly comprises an atmospheric distillation, in which the liquid effluent obtained after gas / liquid separation is fractionated by atmospheric distillation into at least one atmospheric distillate fraction and at least one atmospheric residue fraction, then a vacuum distillation in which the atmospheric residue fraction obtained after atmospheric distillation is fractionated by vacuum distillation into at least one vacuum distillate fraction and at least one vacuum residue fraction.The vacuum distillate fraction typically contains vacuum gas oil type fractions.

[0171] Advantageously, the separation section may also comprise means for washing at least one separated cut by contact with an aqueous solution.

[0172] This washing makes it possible in particular to eliminate the ammonium chloride salts originating essentially from the pyrolysis oil fraction. These salts are formed by reaction between the chloride ions, released by the hydrogenation of the chlorinated compounds in HCl form during steps a) and b) then dissolution in water, and the ammonium ions, generated by the hydrogenation of the nitrogen compounds in the form of NH3 during steps a) and b) and / or supplied by injection of an amine then dissolution in water. The washing thus makes it possible to limit the risks of blockage, in particular in the transfer lines and / or in the sections of the process of the invention, due to the precipitation of the ammonium chloride salts. It also makes it possible to eliminate the hydrochloric acid formed by the reaction of the hydrogen ions and the chloride ions and therefore to limit corrosion in the downstream equipment.

[0173] According to a preferred embodiment, the separation step (c) comprises: c1) a first separation step carried out at a temperature higher than the precipitation temperature of ammonium halides to obtain at least a first gaseous fraction and a liquid effluent, c2) a second separation step, supplied with a first gaseous fraction and at least a portion of the liquid effluent from step c1) and an aqueous solution, said step being carried out at a temperature lower than the precipitation temperature of ammonium halides to obtain at least a second gaseous fraction, an aqueous effluent and a liquid product.

[0174] The objective of this separation by the combination of step c1) of hot separation followed by step c2) of cold separation / washing is to eliminate chlorine in the form of ammonium chloride salts.

[0175] The chloride ions released by the hydrogenation of chlorinated compounds in HCl form during steps a) and b) (hydrodechlorination) and the ammonia generated by the hydrogenation of nitrogen compounds in the form of NH3 during step b) in particular (hydrodenitrogenation), are largely released into the gaseous effluent thanks to the hot separation of step c1). Indeed, the high temperature of this separation step c1) prevents the precipitation of ammonium chloride salts which are formed by reaction between chloride ions and ammonium ions. The separation at a lower temperature in step c2) of the gaseous effluent and part of the liquid effluent causes these ammonium chloride salts to precipitate. Washing with an aqueous solution (generally water) or with a basic aqueous solution (soda ash solution, amine(s) solution for example) in this step c2) allows these salts to be dissolved in the aqueous effluent. This produces a hydrocarbon effluent freed from chlorine.

[0176] The precipitation temperature of ammonium halides is defined as the temperature (under given conditions, such as concentration and pressure) at which gaseous ammonia and hydrogen halides precipitate, either by reacting to form solid crystals of ammonium halides or by dissolving in water. The precipitation temperature depends on the halide concentrations and pressure according to thermodynamic principles. The precipitation temperature of ammonium halides is generally between 150 and 300°C under the conditions of use of the present process.

[0177] The separation equipment or tanks may include at the bottom a zone allowing the separate decantation of a hydrocarbon fraction and an aqueous fraction containing chloride salts, or even include a gas washing column by contact with water or a basic solution.

[0178] (d) Further processing step(s) (optional)

[0179] One or more further treatment steps (d) of the liquid product(s) from separation step c) may be carried out.

[0180] Such step d) may comprise at least one step chosen from the list consisting of hydrotreatment, steam cracking, fluidized bed catalytic cracking, hydrocracking, deasphalting, extraction of lubricating oils. These examples of further treatment are not exhaustive.

[0181] The various hydrocarbon products which may result from separation step c) may in fact be sent to different processes in the refinery, and the details of all these post-treatments are not described here being generally known to those skilled in the art.

[0182] Alternatively, naphtha, kerosene and diesel bases can be used in refineries to produce automotive and aviation fuels, such as super-fuels, jet fuels and diesel, either directly or after possible hydrotreatment.

[0183] According to another variant, part of the gases comprising hydrocarbons with 2 to 4 carbon atoms, bases such as naphtha, kerosene and diesel can be recovered in a steam cracking unit in order to obtain in particular light olefins which can be used as monomers in the manufacture of polymers.

[0184] According to yet another variant, naphtha, kerosene and diesel type bases can be recovered in a fluidized bed catalytic cracking unit (FCC for Fluid Catalytic Cracking according to the Anglo-Saxon terminology) or in a hydrocracking unit.

[0185] Alternatively, the vacuum distillate can be recycled in a hydrocracking unit. Alternatively, the atmospheric residue and / or vacuum residue (unconverted) can be sent to a catalytic cracking (FCC), hydrocracking or dealphating process.

[0186] Alternatively, the atmospheric residue fraction and / or the vacuum residue fraction may be used as low-sulfur marine fuels, including marine distillates and / or marine residual fuels, generally referred to as bunker oil. In particular, it is possible to produce a low-sulfur marine residual fuel without the need to add a flux. Fluxes, generally selected from light catalytic cracking (LCO) cut oils, heavy catalytic cracking (HCO) cut oils, catalytic cracking residue, kerosene, diesel oil, vacuum distillate and / or decanted oil, are generally added to lower the viscosity of a bunker oil.The presence of pyrolysis oil as a co-feed in the treatment of a heavy feedstock of fossil origin makes it possible to directly obtain a fuel oil that meets the specifications in terms of sulfur, sediment and viscosity without the need to add a fluxing agent. The sulfur specifications for a fuel oil are a sulfur content of less than 0.5% wt / ppm (ISO8217). RMG 380 is a most common bunker fuel grade according to ISO8217 and the viscosity specification for RMG 380 grade bunker fuel is a viscosity of less than 380 cST at 50°C. Another very restrictive recommendation is the sediment content after aging according to ISO 10307-2 (also known as IP390) ​​which must be less than or equal to 0.1%.

[0187] List of figures

[0188] Figure 1 schematically illustrates an embodiment of the method according to the invention.

[0189] Figure 1 describes a simplified diagram of implementation of the reactor chain of the invention without limiting its scope. For the sake of simplicity, only the reactors are shown, but it is understood that all the equipment necessary for operation is present (tanks, pumps, exchangers, furnaces, columns, etc.). Only the main streams containing the hydrocarbons are shown, but it is understood that streams of hydrogen-rich gas (make-up or recycle) can be injected at the inlet of each catalytic bed or between two beds.

[0190] The feedstock comprising a heavy hydrocarbon fraction 1 and a minor fraction of plastic and / or tire and / or CSR pyrolysis oil 2, optionally pretreated (not shown), enters a fixed-bed reaction unit comprising permutable guard reactors consisting of reactors Ra and Rb, to carry out a hydrodemetallization step a). The pyrolysis oil fraction may be premixed with the heavy hydrocarbon fraction of the feedstock before entering the first hydrodemetallization reactor. Another variant is the separate injection of the pyrolysis oil fraction and the heavy hydrocarbon fraction into the first hydrodemetallization reactor (not shown). The effluent 3 from the hydrodemetallization step a) in permutable guard reactors is sent to a fixed-bed reaction section consisting of reactors R1, R2 and R3 to carry out the hydrotreatment step b).The fixed bed hydrotreatment reactors may for example be loaded respectively with hydrodemetallization, transition and hydrodesulfurization catalysts. The effluent 4 from the fixed bed hydrotreatment stage is sent to a separation section 5 to carry out the separation stage and separate a gaseous effluent 6 and at least one liquid product 7.

[0191] The operation of the swappable reactors is as follows:

[0192] Each Ra and Rb reactor can be taken offline so that the catalyst can be changed without stopping the rest of the unit. This catalyst change (rinsing, unloading, reloading, sulfurization) is generally enabled by a conditioning section (not shown). In sequence 1, the feed passes through reactors Ra and Rb, then R1, R2 and R3. When the catalyst in reactor Ra is no longer sufficiently active (metal poisoning and / or coking) and / or the clogging reaches too high a pressure drop, the catalyst changeover occurs. In sequence 2, reactor Ra is taken offline, the feed enters reactor Rb directly, then passes through R1, R2 and R3. During this sequence 2, the spent catalyst in reactor Ra is unloaded and reactor Ra is reloaded with fresh catalyst.In sequence 3, reactor Ra containing the fresh catalyst is put online in such a way that the feed first passes through reactor Rb containing a partially spent catalyst, then reactor Ra, then R1, R2 and R3. When the catalyst in reactor Rb is no longer sufficiently active and / or the clogging reaches too high a pressure drop, another permutation for catalyst change occurs. During this sequence 4, the spent catalyst in reactor Rb is discharged and reactor Rb is reloaded with a fresh catalyst; the feed enters directly into reactor Ra, then passes through R1, R2 and R3. In sequence 5, reactor Rb containing the fresh catalyst is put online in such a way that the feed first passes through reactor Ra containing a partially spent catalyst, then reactor Rb, then R1, R2 and R3. Sequence 5 being identical to sequence 1, this demonstrates the cyclical nature of the proposed operation.The following table gives examples of sequences that can be carried out according to Figure 1:.

[0193] Table 1 Similarly, there may be more than 2 permutable reactors in the hydrodemetallization section in permutable reactors. Similarly, there may be more or less than 3 fixed bed hydrotreatment reactors, the representation by R1, R2 and R3 being given for purely illustrative purposes.

[0194] Analysis methods used The analysis methods and / or standards used to determine the characteristics of the various flows, in particular the load to be treated and the effluents produced, are known to those skilled in the art. They are in particular listed in Table 2 below for information purposes. Other methods deemed equivalent may also be used, in particular equivalent IP, EN or ISO methods.

[0195] Table 2

[0196] (1> MAV method described in the article: C. Lôpez-Garcia et al., Near Infrared Monitoring of Low Conjugated Diolefins Content in Hydrotreated FCC Gasoline Streams, Oil & Gas Science and Technology - Rev. IFP, Vol. 62 (2007), No. 1, pp. 57-68

[0197] Examples

[0198] The examples below aim to show certain performances of the method according to the invention.

[0199] These examples illustrate the possibility of co-processing plastic pyrolysis oil in a Hyvahl® type treatment process that eliminates impurities naturally present in heavy feedstocks of fossil origin. The hydrotreated effluents can be used as a base for manufacturing fuels, lubricants or any other product traditionally derived from oil refining. We also demonstrate the ability of the supported catalyst present in the Hyvahl® process to capture impurities present in the pyrolysis oil and thus valorize this feedstock while facilitating the post-treatment of effluents from the hydrotreatment of the heavy feedstock that meet the sulfur (0.5% wt.) and viscosity (380 cSt at 50°C) specifications required by ISO 8217 for a bunker fuel type RMG 380.

[0200] Example 1 is a comparative example illustrating the performance of the treatment process for a reference load (vacuum residue) without plastic pyrolysis oil.

[0201] Example 2 illustrates the performance of a treatment process with a feedstock comprising a fraction of plastic pyrolysis oil and a fraction of the reference feedstock (vacuum residue) used in Example 1. The mixture was implemented during a pre-stage of homogenization of the medium (optional stage).

[0202] Charge :

[0203] The heavy fraction (I) of the feedstock is a vacuum residue directly from the distillation of a crude oil (called straight-run according to Anglo-Saxon terminology (RSV-SR)). The plastic pyrolysis oil fraction (II) of the feedstock is a pyrolysis oil from a mixture of plastics and containing a significant level of impurities.

[0204] The main characteristics of these two fractions of the load are presented in Table 3 below. Table 3

[0205] (*) LD: Detection Limit

[0206] The treatment process involves the use of two swappable reactors Ra and Rb in the first hydrodemetallation stage (H DM) upstream of a hydrotreatment section composed of 4 fixed bed reactors (R1, R2, R3 and R4). The operating conditions are similar for both examples and are summarized in Table 4 below.

[0207] Table 4 Saxon) Results and overall performance: The results concerning the treatment performance of the RSV load with (Example 2) or without (Example 1) plastic pyrolysis oil are detailed in Table 5 below.

[0208] Table 5 (*) LD: Limit of Detection

[0209] It is observed that the presence of plastic pyrolysis oil eliminates the need to add a fluxing cut to achieve the sulfur and viscosity specifications imposed by the ISO 8217 standard for a bunker fuel oil of type RMG 380. Furthermore, in the co-treatment of the plastic pyrolysis oil of example 2, the formulation of the bunker fuel does not require the use of the entire [180-350°C] cut, contrary to what is observed in example 1. This “excess” cut can therefore be sent to the steam cracker with the PI- 180°C cut or serve as a basis for the formulation of other fuels.

[0210] It can also be observed that the total effluents from the hydrotreatment of the mixture of the RSV cut with the plastic pyrolysis oil, present Si and Cl contents below the analytical detection limit, which indicates that the catalysts and operating conditions used in the treatment process are adequate to eliminate the impurities.

Claims

Claims 1. Process for treating a feedstock comprising a heavy fraction of hydrocarbons of fossil origin having an initial boiling point of at least 340°C and a final boiling point of at least 550°C and containing sulfur and nitrogen, and a fraction of pyrolysis oil from plastics and / or tires and / or solid recovered fuels, said pyrolysis oil fraction constituting less than 50% by weight of said feedstock, said process comprising: a) a hydrodemetallization step carried out in a fixed-bed reaction section comprising at least two permutable reactors, said section being fed at least by said feedstock and a gas stream comprising hydrogen, in the presence of at least one hydrodemetallization catalyst, at a temperature between 300 and 500°C, an absolute pressure between 5 MPa and 35 MPa and an hourly volumetric velocity between 0.1 and 5.0 h' 1, b) a hydrotreatment step carried out in a reaction section comprising at least one fixed-bed reactor, said section being fed at least with said effluent from step a) and optionally a gaseous flow comprising hydrogen, in the presence of at least one hydrotreatment catalyst, at a temperature between 300 and 500°C, an absolute pressure between 5 MPa and 35 MPa and an hourly volumetric flow rate between 0.1 and 5.0 h- 1 c) a step of separating the effluent from step b) carried out in a separation section leading to a gaseous fraction and at least one liquid product.

2. Method according to claim 1, comprising at least one step aO) of pretreatment of the pyrolysis oil fraction of plastics and / or tires and / or solid recovered fuels, said pretreatment step being carried out upstream of step a), and comprising an adsorption step and / or a filtration step and / or a centrifugation step and / or an electrostatic separation step and / or a step of washing using an aqueous solution and / or a gas stripping step.

3. Process according to any one of the preceding claims, in which the pyrolysis oil fraction constitutes between 1% and 45% by weight of said feedstock, preferably between 2% and 30% by weight of said feedstock, preferably between 2% and 25% by weight of said feedstock.

4. A process according to any one of the preceding claims, wherein the feedstock consists of said pyrolysis oil fraction and said heavy hydrocarbon fraction, said pyrolysis oil fraction constituting between 1% and 45% by weight, preferably between 2% and 30% by weight, more preferably between 2% and 25% by weight of said feedstock and the heavy hydrocarbon fraction constituting between 55% and 99% by weight, preferably between 70% and 98% by weight, more preferably between 75% and 98% by weight of said feedstock.

5. Process according to any one of the preceding claims, in which the heavy hydrocarbon fraction is chosen from the list consisting of an atmospheric residue or a vacuum residue from the atmospheric and / or vacuum distillation of a crude oil or an effluent from a thermal conversion, hydrotreatment, hydrocracking or hydroconversion unit, an aromatic cut extracted from a lubricant production unit, a deasphalted oil from a deasphalting unit, an asphalt from a deasphalting unit, a residual fraction from the direct liquefaction of coal.

6. A process according to claim 5, wherein the heavy hydrocarbon fraction is a vacuum residue and / or an atmospheric residue.

7. Process according to any one of the preceding claims, in which the hydrodemetallization catalyst of step a) comprises from 0.5% to 10% by weight of nickel, expressed as nickel oxide NiO relative to the total weight of the catalyst, and from 1% to 30% by weight of molybdenum, expressed as molybdenum oxide MoOa relative to the total weight of the catalyst, on a mineral support chosen from the group consisting of alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals.

8. Process according to any one of the preceding claims, in which the hydrotreatment catalyst of step b) comprises from 0.5% to 10% by weight of nickel, expressed as nickel oxide NiO relative to the total weight of the catalyst, and from 1% to 30% by weight of molybdenum, expressed as molybdenum oxide MoOa relative to the total weight of the catalyst, on a mineral support chosen from the group consisting of alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals.

9. Method according to any one of the preceding claims, in which said separation section in step c) comprises means for washing by contact with an aqueous solution.

10. Method according to claim 9, in which separation step c) comprises: c1) a first separation step carried out at a temperature higher than the precipitation temperature of ammonium halides to obtain at least a first gaseous fraction and a liquid effluent, c2) a second separation step, fed with a first gaseous fraction and at least a portion of the liquid effluent from step c1) and an aqueous solution, said step being carried out at a temperature lower than the precipitation temperature of ammonium halides to obtain at least a second gaseous fraction, an aqueous effluent and a liquid product.

11. Method according to any one of the preceding claims, further comprising a step d) of further treatment of the at least one liquid product from step c), said step d) comprising at least one step chosen from the list consisting of hydrotreatment, steam cracking, fluidized bed catalytic cracking, hydrocracking, deasphalting, extraction of lubricating oils.

12. A process according to any one of the preceding claims, wherein, in step (a), the pyrolysis oil fraction and the heavy hydrocarbon fraction of the feedstock are premixed before being introduced into one of said permutable reactors.

13. A process according to any one of claims 1 to 11, wherein, in step (a), the pyrolysis oil fraction of the feedstock is introduced separately from the heavy hydrocarbon fraction into one of said permutable reactors.

14. Process according to claim 13, in which step (a) comprises a step of preheating said heavy hydrocarbon fraction, preferably at a temperature between 280°C and 450°C, and a step of preheating the pyrolysis oil fraction carried out at a lower temperature than that of said heavy hydrocarbon fraction, before introducing the feed into one of said permutable reactors.

15. Product obtained by the process according to one of claims 1 to 14.

16. Product according to claim 15, comprising a silicon content of less than or equal to 10 ppm by weight, and / or a chlorine element content of less than or equal to 10 ppm by weight relative to the weight of the product.

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