Method for treating pyrolysis oil for recycling in catalytic cracking units or hydrorefining units

Abstract

The present invention relates to a method for treating a feedstock comprising pyrolysis oil from plastics and / or tires and / or solid recovered fuels containing halogenated compounds, said method comprising: a) a hydrotreating step to obtain a partially hydrotreated effluent having a reduced content of halogenated compounds; b) a separation step in which the hydrotreated effluent from step a) and an aqueous solution are fed to obtain a gaseous effluent, an aqueous effluent and a partially hydrotreated hydrocarbon effluent; and c) a step of fluidized bed catalytic cracking or hydrotreating of a petroleum feedstock and / or a feedstock resulting from biomass conversion, in which the partially hydrotreated hydrocarbon effluent is introduced as a co-feed without a prior separate hydrotreatment step at higher temperature and / or pressure, and the mixture of petroleum and / or biomass feedstock and the partially hydrotreated hydrocarbon effluent has a halogenated compound content of 10 ppm or less by weight.

Description

[Technical Field]

[0001] The present invention relates to a method for treating pyrolysis oil of plastics and / or tires and / or solid recovered fuels (SRF), resulting in a partially hydrotreated pyrolysis oil that can be upgraded as a co-feed with petroleum feedstocks and / or feedstocks resulting from biomass conversion in hydrogen-using refinery units, such as fluid catalytic cracking units or hydrorefining units, such as hydrotreating, hydrocracking or hydroconversion units. More particularly, the present invention relates to a method for treating pyrolysis oil with a view to eliminating its halogenated compounds, allowing for easy upgrading of this oil in existing refinery units. [Background technology]

[0002] Plastic waste is generally a mixture of several polymers, such as polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, or polystyrene. Furthermore, depending on the application, plastics may contain other compounds in addition to polymers, such as plasticizers, pigments, dyes, or residues of polymerization catalysts. Plastic waste may also contain small amounts of biomass, for example, originating from household waste. Waste treatment, especially storage, mechanical treatment, sorting, and pyrolysis on the one hand, and storage and transportation of pyrolysis oil on the other hand, can also cause corrosion.

[0003] As for tires, they are mainly composed of rubber (a mixture of elastomers of crosslinked synthetic and natural rubber type with the addition of adjuvants of silica, resin, sulfur, zinc oxide, carbon black, etc.) for their elastic properties, and textile and metal fibers for their reinforcing properties.

[0004] Solid recovered fuel (SRF), also known as refuse-derived fuel (RDF), is solid, non-hazardous waste prepared with a view to energy upgrading, whether derived from household and similar waste, waste from economic activity, or waste from construction and demolition. SRF is 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 cars, electrical and electronic equipment (WEEE)), household and commercial waste, certain municipal waste, plastic waste, and residues from recycling various types of waste, including textiles or wood, among others. SRF commonly contains plastic waste.

[0005] The plastics or recycled tires or other SRFs coming out of the collection and sorting channels can be subjected to a pyrolysis process to obtain, among other things, pyrolysis oils, which generally contain many impurities, in particular halogenated compounds, especially chlorine-based compounds, but also diolefins, olefins, metals, in particular iron, silicon, or other heteroelements, such as sulfur, oxygen and nitrogen, as well as insoluble substances.

[0006] These plastic and / or tire and / or SRF pyrolysis oils are generally incinerated to generate electricity and / or used as fuel for industrial or municipal heating boilers.

[0007] Another route for upgrading pyrolysis oils is to use them as feedstock for steam cracking units to (re)produce olefins, which are the constituent monomers of certain polymers. However, plastic and / or tire pyrolysis oils often have high impurity contents and are not compatible with steam cracking units or units located downstream of the steam cracking unit, especially polymerization and selective hydrogenation processes.

[0008] One method for removing these impurities contained in pyrolysis oil is hydrotreating in the presence of a catalyst. Steam cracking units require very high feedstock purity, particularly low contents of chlorine, diolefins, olefins, metals, and sulfur. Hydrotreating upstream of steam cracking is then often carried out in several steps under very stringent conditions, particularly with respect to temperature and pressure, to achieve the required specifications. Such methods are described, for example, in Patent Documents 1 to 5.

[0009] Another method for upgrading plastic and / or tire pyrolysis oils is to use these pyrolysis oils as feedstock in fluid catalytic cracking (FCC) units, primarily for producing gasoline. Such methods are described, for example, in U.S. Pat. Nos. 6,131,529, 6,149,549, 6,151,554, 6,163,564, 6,164,575, 6,165,582, 6,165,597, 6,165,598, 6,165,59 ...

[0010] Although specification requirements are different and often lower with respect to purity for FCC feedstocks, the upstream hydrotreating performed to remove impurities described in the prior art is also generally carried out under very stringent conditions. Patent document 10, for example, describes FCC pretreatment by hydrotreating at temperatures of 349-415°C (660-780°F) and pressures of 6.8-13.8 MPa (68-138 bar, 1000-2000 psi).

[0011] The present invention proposes a method for the mild hydrotreatment of pyrolysis oils of plastics and / or tires and / or SRF, which makes it possible in particular to reduce the content of halogenated compounds, in particular chlorine, to obtain a pyrolysis oil stripped of most halogenated compounds, which can then be sent as co-feed to a refinery unit, such as an FCC unit, or to a hydrogen-based hydrotreating unit, such as a hydrocracking, hydrotreating or hydroconversion unit, with a petroleum feedstock and / or a feedstock resulting from biomass conversion.

[0012] Chlorine is generally a limiting contaminant when processing pyrolysis oil in existing units of refineries. Indeed, even at low contents (<10 ppm by weight, or even <5 ppm by weight), chlorine (in the form of HCl) is a cause of corrosion that can occur in existing units, the metallurgy of which is generally not designed to withstand chlorine levels in the feedstock above 10 ppm by weight, or even above 5 ppm by weight.

[0013] Unlike the hydrotreating processes described in the prior art, the process according to the invention is directed towards mild hydrotreating, in particular hydrotreating at low pressure and moderate temperature. The mild operating conditions in hydrotreating, combined with the separation step with washing, make it possible to largely remove halogenated compounds while retaining as much as possible diolefins and olefins that can be upgraded, for example in FCC (to produce propylene).

[0014] The process according to the present invention focuses primarily on the removal of halogenated compounds in order to make the pyrolysis oil suitable as a feedstock for downstream units. The process according to the present invention does not necessarily aim at complete hydrotreating of the oil. Other impurities (metals, silicon, nitrogen, etc.) contained in the pyrolysis oil are not necessarily completely removed during the process according to the present invention, but the operating conditions make it possible to remove at least a portion of them. These impurities may be converted or removed in downstream units, and the remaining content of the impurities is compatible with these units.

[0015] The "mild" hydrotreatment of the present invention is a hydrotreatment carried out under carefully selected conditions of pressure, temperature and hourly space velocity, which is generally milder than conventional hydrotreatments known from the prior art, which aim to remove all impurities. The hydrotreatment of the present invention makes it possible in particular to largely remove halogenated compounds, while retaining diolefins and olefins as much as possible.

[0016] The aim of the present invention is to propose a method for treating plastic and / or tire pyrolysis oils that is cheap, easy to implement and can be easily integrated into existing refinery units. The fact that mild operating conditions are used makes it possible to minimize the hydrogen consumption and therefore the costs of this refinery, as well as the operating and investment costs, while removing as much of the chlorine content as possible.

[0017] Furthermore, the process according to the invention can be carried out in a unit dedicated to pyrolysis oil, thus in a low-volume unit, which makes it possible to obtain a partially hydrotreated pyrolysis oil, the content of halogenated compounds of which is low enough to be sent directly to co-processing in existing refinery units, without the need for the existing units to be modified.

[0018] The unit of the process according to the invention can be easily integrated into a refinery unit and, due to the low pressure required, can also use hydrogen supply units already present in the refinery. [Prior art documents] [Patent documents]

[0019] [Patent Document 1] International Publication No. 2016 / 142808 [Patent Document 2] International Publication No. 2016 / 142809 [Patent Document 3] International Publication No. 2018 / 055555 [Patent Document 4] International Publication No. 2021 / 110395 [Patent Document 5] International Publication No. 2021 / 165178 [Patent Document 6] U.S. Patent No. 10,442,997 [Patent Document 7] International Publication No. 2021 / 133893 [Patent Document 8] International Publication No. 2021 / 133889 [Patent Document 9] International Publication No. 2021 / 133895 [Patent Document 10] International Publication No. 2021 / 201932 Summary of the Invention [Means for solving the problem]

[0020] (Summary of the Invention) More specifically, the present invention relates to a method for treating a pyrolysis feedstock, the pyrolysis feedstock comprising pyrolysis oils of plastics and / or tires and / or solid recovered fuels containing halogenated compounds, said method comprising the steps of: a) Hydrotreating step, which is carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst; at least a gas stream containing pyrolysis feedstock and hydrogen is fed to the hydrotreating reaction section, and the average temperature during the hydrotreating reaction section is 100°C to 220°C, the hydrogen partial pressure is 1.0 to 3.0 MPa (absolute), and the hourly space velocity is 0.05 to 5 h -1 and the hydrogen coverage is the volume of pyrolysis feedstock (m 3 ) 5-50Nm of hydrogen per 3 obtaining a partially hydrotreated effluent having hydrocarbon compounds with a reduced halogen content; b) a separation step of feeding the partially hydrotreated effluent from step a) and the aqueous solution to obtain at least a gaseous effluent, an aqueous effluent, and a partially hydrotreated hydrocarbon effluent; c) a step of fluid catalytic cracking or hydrorefining of a petroleum feedstock and / or a feedstock resulting from biomass conversion; introducing at least a portion of the partially hydrotreated hydrocarbon effluent from step b) as a co-feed; introducing said partially hydrotreated hydrocarbon effluent from step b) without first passing it through another hydrotreatment step carried out at a temperature and / or pressure higher than that of step a); said mixture of said feedstock resulting from petroleum feedstock and / or biomass conversion and the partially hydrotreated hydrocarbon effluent from step b) has a halogen content of not more than 10 ppm by weight.

[0021] According to a variant, the weight ratio of the stream of partially hydrotreated hydrocarbon effluent from step b) to the stream of petroleum feedstock and / or feedstock resulting from biomass conversion introduced into step c) is less than 1.

[0022] According to a variant, the pyrolysis feedstock consists of pyrolysis oils of plastics and / or tires and / or solid recovered fuels.

[0023] According to a variant, the content of halogenated compounds in the pyrolysis feedstock is between 1 and 5000 ppm by weight.

[0024] According to one variant, the hydrotreating catalyst of step a) comprises a support chosen from alumina, silica, silica-alumina, magnesia, clay and mixtures thereof, and a hydro-dehydrogenation functional element comprising either at least one element from group VIII and at least one element from group VIB, or at least one element from group VIII.

[0025] According to a variant, the method comprises at least one step a0) of pre-treating the pyrolysis feedstock comprising pyrolysis oil of plastics and / or tires and / or SRF, said pre-treatment 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 a sedimentation step and / or an electrostatic separation step and / or a washing step with an aqueous solution and / or a gas stripping step.

[0026] According to a variant, the petroleum feedstock is chosen from gasoline, gas oil, vacuum gas oil, atmospheric residue, vacuum residue, atmospheric distillate, vacuum distillate, heavy fuel oil, oil, wax and paraffin, waste oil, deasphalted residue or crude oil, petroleum feedstocks derived from thermal or catalytic conversion processes, or mixtures of such feedstocks.

[0027] According to a variant, the biomass-derived feedstock is chosen from vegetable oils, oils from algae or algal oils, fish oils, waste edible oils, and fats of vegetable or animal origin; fatty acid methyl esters of vegetable and / or animal origin, fatty acid methyl esters from waste edible vegetable oils, feedstocks derived from thermal or catalytic biomass conversion processes, or mixtures of such feedstocks.

[0028] According to an alternative embodiment, the reaction section of step a) uses at least two reactors operating in a sequence-variable mode.

[0029] According to a variant, the fluid catalytic cracking step c) is carried out in a substantially vertical reactor in the fluid catalytic cracking reaction section, either in upflow mode or downflow mode, in the presence of a zeolite catalyst, at a reactor temperature of 450°C to 600°C, with a contact time in the reactor of less than 1 minute.

[0030] According to a variant, the hydrorefining step c) is a hydrotreating step carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst, the hydrotreating reaction section being fed with at least a gas stream containing hydrogen, the hydrotreating reaction section being used at an average temperature between 180°C and 480°C, a hydrogen partial pressure between 0.5 and 25 MPa (absolute) and an hourly space velocity between 0.1 and 20 h -1 and the hydrogen coverage is the ratio of the volume of the feedstock (m 3 ) 50-5000Nm of hydrogen per 3 is.

[0031] According to a variant, the hydrorefining step c) is a hydrocracking step carried out in a hydrocracking reaction section containing at least one hydrocracking catalyst, the hydrocracking reaction section being fed with a gas stream containing hydrogen, the hydrocracking reaction section being used at an average temperature of 250°C to 480°C, a hydrogen partial pressure of 2 to 25 MPa (absolute) and an hourly space velocity of 0.5 to 40 h -1 and the hydrogen coverage is the ratio of the volume of the feedstock (m 3 ) 80-5000Nm of hydrogen per 3 is.

[0032] According to a variant, the hydrorefining step c) is a hydroconversion step carried out in a hydroconversion reaction section containing at least one hydroconversion catalyst, the hydroconversion reaction section being fed with a gas stream containing hydrogen, the average temperature used in the hydroconversion reaction section being between 340°C and 550°C, the hydrogen partial pressure being between 2 and 38 MPa (absolute), and the hourly space velocity being between 0.05 and 10 h -1 and the hydrogen coverage is the ratio of the volume of the feedstock (m 3 ) 50-5000Nm of hydrogen per 3 is.

[0033] In the remainder of the text, the term "pyrolysis oil" is understood to mean, unless otherwise stated, oil resulting from the pyrolysis of plastics and / or tires and / or SRF.

[0034] According to the invention, pressures are absolute pressures, also denoted abs., and are given in MPa absolute (or MPa(absolute)) unless otherwise stated.

[0035] According to the present invention, the expressions "of between A and B" and "between A and B" are equivalent and mean that the upper and lower limits of the interval are included in the range of values ​​stated. If this is not the case and if the upper and lower limits are not included in the range stated, such clarification is introduced by the present invention.

[0036] Within the meaning of the present invention, various parameter ranges for a given process, such as pressure ranges and temperature ranges, can be used alone or in combination, e.g., for the purposes of the present invention, a range of preferred pressure values ​​can be combined with a range of more preferred temperature values.

[0037] In the following text, specific and / or preferred embodiments of the present invention are described, which can be implemented separately or combined together without any combination restrictions, if the combination is technically feasible.

[0038] Subsequently, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, published by CRC Press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, group VIII (or group VIIIB) according to the CAS classification corresponds to the metals in columns 8, 9, and 10 according to the new IUPAC classification.

[0039] The metal content is measured by X-ray fluorescence. DETAILED DESCRIPTION OF THE INVENTION

[0040] (Detailed explanation) (pyrolysis feedstock) According to the present invention, "plastic pyrolysis oil or tire pyrolysis oil or SRF pyrolysis oil" is an oil, advantageously in liquid form at ambient temperature, resulting from the pyrolysis of plastics, preferably from the pyrolysis of plastic waste, in particular from collection and sorting channels, or from the pyrolysis of used tires, or from the pyrolysis of SRF. It contains in particular a mixture of hydrocarbon compounds, in particular paraffins, olefins (mono- and / or diolefins), naphthenes, and aromatic compounds. At least 80% by weight of these hydrocarbon compounds preferably have a boiling point below 700°C, preferably below 550°C. In particular, depending on the origin of the pyrolysis oil, it can contain 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 aromatic compounds, with the sum of paraffins, naphthenes, olefins, and aromatic compounds being understood to be equal to 100% by weight of hydrocarbon compounds.

[0041] Pyrolysis oils can contain diolefins. The diolefin content is generally determined indirectly as the maleic anhydride value (MAV). This method is based on the Diels-Alder addition reaction between conjugated diolefins and maleic anhydride. The method for determining MAV is described in C. Lopez-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 the weight (mg) of maleic anhydride reacted with 1 g of sample (mg / g). MAV varies between 5 and 100 mg / g in pyrolysis oils.

[0042] The density of pyrolysis oil is typically 0.75 g / cm, measured at 15°C according to ASTM D4052 method. 3 ~0.99g / cm 3, preferably 0.75 g / cm 3 ~0.95g / cm 3 is.

[0043] Pyrolysis oils may contain, and usually do contain, impurities such as metals, especially iron, silicon, or halogenated compounds, especially chlorinated compounds. These impurities may be present in high concentrations in pyrolysis oils, and may be contributed by halogenated compounds, for example, up to 500 ppm by weight, up to 700 ppm by weight, or up to 1000 ppm by weight, or even up to 5000 ppm by weight of halogen elements (especially chlorine, but also bromine, fluorine, iodine, or astatine), typically 1 to 1000 ppm by weight, or 1 to 700 ppm by weight, or 1 to 500 ppm by weight. Pyrolysis oils may contain up to 500 ppm by weight, up to 700 ppm by weight, or up to 1000 ppm by weight, or even up to 5000 ppm by weight of chlorine, typically 1 to 1000 ppm by weight, or 1 to 700 ppm by weight, or 1 to 500 ppm by weight of chlorine, typically 1 to 1000 ppm by weight, or 1 to 700 ppm by weight, or 1 to 500 ppm by weight.

[0044] Oils may contain up to 200 ppm by weight or up to 1500 ppm by weight of metal or metalloid elements, generally 1-200 ppm by weight or 1-1500 ppm by weight. Alkali metals, alkaline earth metals, transition metals, post-transition metals, and metalloids can be grouped together with metallic contaminants, referred to as metal or metalloid elements. In particular, metal or metalloid elements include silicon, iron, or both. Pyrolysis oils may contain up to 200 ppm by weight or up to 1000 ppm by weight of silicon, generally 1-200 ppm by weight, 1-1000 ppm by weight, or 1-500 ppm by weight of silicon. Pyrolysis oils may contain up to 50 ppm by weight or up to 100 ppm by weight of iron, generally 1-50 ppm by weight or 1-100 ppm by weight of iron. Pyrolysis oil may also contain phosphorus, sodium, calcium, potassium and magnesium.

[0045] The pyrolysis oil may also contain other impurities, such as heteroelements, in particular contributed by sulfur compounds, oxygen compounds and / or nitrogen compounds, generally with a heteroelement content of less than 40,000 ppm by weight, preferably less than 15,500 ppm by weight, generally between 1 and 40,000 ppm by weight or between 1 and 15,500 ppm by weight.

[0046] The sulfur compounds are generally present in a content of sulfur compounds of less than 15,000 ppm by weight, preferably less than 10,000 ppm by weight, generally between 1 and 15,000 ppm by weight or between 1 and 10,000 ppm by weight.

[0047] The oxygen compounds are generally present in a content of less than 15,000 ppm by weight, preferably less than 10,000 ppm by weight, generally between 1 and 15,000 ppm by weight or between 1 and 10,000 ppm by weight of oxygen compounds.

[0048] The nitrogen compounds are generally present in a content of less than 10,000 ppm by weight, preferably less than 5000 ppm by weight, generally between 1 and 10,000 ppm by weight or between 1 and 5000 ppm by weight of nitrogen compounds.

[0049] The content of sulfur, oxygen and / or nitrogen compounds often depends on the origin of the oil. Thus, tire pyrolysis oils generally contain more heteroelements, especially sulfur compounds, than plastic pyrolysis oils.

[0050] The pyrolysis oil may also contain other impurities, for example heavy metals such as mercury, arsenic, zinc and lead, for example up to 100 ppb by weight or up to 200 ppb by weight of mercury or arsenic, typically 1 to 200 ppb by weight or 1 to 100 ppb by weight of heavy metals.

[0051] The pyrolysis feedstock for the process according to the invention comprises pyrolysis oil of at least one plastic and / or tire and / or SRF. The feedstock may consist exclusively of one or more pyrolysis oils. Preferably, the feedstock comprises at least 50% by weight, preferably 70% to 100% by weight, of pyrolysis oil, i.e. preferably 50% to 100% by weight, preferably 70% to 100% by weight, of plastic pyrolysis oil, relative to the total weight of the feedstock.

[0052] Particularly preferably, the pyrolysis feedstock for the process according to the invention consists exclusively of pyrolysis oils of one or more plastics and / or tyres and / or SRF.

[0053] In the case of a mixture of plastic pyrolysis oil, tire pyrolysis oil and / or SRF pyrolysis oil, this mixture can be produced in any proportion.

[0054] According to another variant, the pyrolysis feedstock of the process according to the invention introduced in step a) can comprise, in addition to one or more pyrolysis oils, conventional petroleum feedstocks or feedstocks resulting from biomass conversion, which are then co-processed with the pyrolysis oils of the feedstock.

[0055] The conventional petroleum feedstock introduced in step a) can advantageously be a fraction or mixture of fractions of naphtha or gas oil type.

[0056] The feedstock resulting from the conversion of biomass introduced in step a) can advantageously be selected from vegetable oils, oils from algae or algae oils, fish oils, waste cooking oils, and fats of vegetable or animal origin, or a mixture of such feedstocks. The vegetable oils can advantageously be completely or partially crude or refined and can be obtained from plants selected from rapeseed, sunflower, soybean, palm, olive, coconut, copra, castor oil plants, cotton plants, peanut oil, linseed oil, and sea kale oil, as well as all oils obtained from sunflower or rapeseed, for example, by genetic modification or hybridization, although this list is not limiting. The animal fats are advantageously selected from blubber and fats and are composed of residues from the food industry or from the catering industry. Frying oils, various animal oils, such as fish oil, tallow, or lard, can also be used. The feedstock resulting from the conversion of biomass may advantageously also be chosen from fatty acid methyl esters of vegetable and / or animal origin, or fatty acid methyl esters from waste edible vegetable oils.

[0057] Feedstocks resulting from biomass conversion can also be selected from feedstocks derived from thermal or catalytic biomass conversion, such as oil produced from biomass, particularly lignocellulosic biomass, using various liquefaction methods, such as hydrothermal liquefaction or pyrolysis. The term "biomass" refers to material derived from recently living organisms, including plants, animals, and their by-products. The term "lignocellulosic biomass" refers to biomass derived from plants or their by-products. Lignocellulosic biomass is composed of carbohydrate polymers (cellulose, hemicellulose) and aromatic polymers (lignin).

[0058] The feedstock resulting from biomass conversion can also advantageously be selected from feedstocks resulting from the paper industry.

[0059] The pyrolysis oils of plastics and / or tires and / or SRF result from thermal or catalytic pyrolysis processes or can also be prepared by hydropyrolysis (pyrolysis in the presence of a catalyst and hydrogen).

[0060] (Preprocessing (optional)) Said feedstock comprising pyrolysis oil of plastics and / or tires and / or SRF can advantageously be pretreated in at least one optional pretreatment step a0) before the hydrotreatment step a) to obtain a pretreated feedstock for feeding to step a).

[0061] According to a variant, this optional pretreatment step a0) makes it possible to reduce the amount of contaminants and solid particles, in particular the amount of iron and / or silicon and / or chlorine, that may be present in the pyrolysis oil-containing feedstock. This optional step a0) particularly allows for the removal of sediments that may form as a result of the unstable nature of pyrolysis oil and / or compatibility problems between two different feedstocks. Therefore, the optional pretreatment step a0) of the pyrolysis oil-containing feedstock is advantageously carried out, particularly when the feedstock contains more than 10 ppm by weight, in particular more than 20 ppm by weight, more particularly more than 50 ppm by weight of metal elements and / or solid particles, and particularly when the feedstock contains more than 5 ppm by weight of silicon, more particularly more than 10 ppm by weight, and even more than 20 ppm by weight. Similarly, the optional pretreatment step a0) of the pyrolysis oil-containing feedstock is advantageously carried out, particularly when the feedstock contains more than 10 ppm by weight of chlorine, in particular more than 20 ppm by weight, more particularly more than 50 ppm by weight.

[0062] Said optional pretreatment step a0) can be carried out by any method known to those skilled in the art making it possible to reduce the amount of contaminants, which may in particular comprise an adsorption step and / or a filtration step and / or a centrifugation step and / or a sedimentation step and / or an electrostatic separation step and / or a washing step with an aqueous solution and / or a gas stripping step.

[0063] The optional pretreatment step a0) is advantageously carried out at a temperature of between 20 and 400° C., preferably between 40 and 350° C., and at a pressure of between 0.15 and 10.0 MPa (absolute), preferably between 0.2 and 7.0 MPa (absolute).

[0064] According to a variant, the optional pretreatment step a0) is carried out in an adsorption section operated in the presence of at least one adsorbent. The adsorbent can be chosen from zeolites, activated carbon, clays, silica or alumina. Preferably, the adsorbent is at least 100 ml 2 / g or more, preferably 200m 2 The specific surface area of ​​said at least one adsorbent is advantageously 600 m 2 / g or less, especially 400m 2 The specific surface area of ​​the adsorbent is the surface area measured by the BET method, i.e. the specific surface area determined by nitrogen adsorption according to standard ASTM D 3663-78, which is derived from the Brunauer-Emmett-Teller method described in the periodical The Journal of the American Chemical Society, 6Q, 309 (1938).

[0065] Advantageously, the adsorbent contains less than 1% by weight of metal elements, preferably no metal elements. Metal elements of the adsorbent should be understood to mean elements of groups 6 to 10 of the Periodic Table of Elements (new IUPAC classification). The residence time of the feedstock in the adsorption section is generally between 1 and 180 minutes.

[0066] The adsorption section of optional step a0) comprises at least one adsorption column, preferably at least two adsorption columns, and preferentially two to four adsorption columns, containing the adsorbent. When the adsorption section comprises two adsorption columns, one operation mode can be a "swing" operation, where one of the columns is online, i.e., in operation, and the other column is in reserve. When the adsorbent of the online column is consumed, this column is isolated, while the reserve column is placed online, i.e., in operation. The consumed adsorbent can then be regenerated in situ and / or replaced with fresh adsorbent, so that the column containing the fresh adsorbent can be brought online again once the other column is isolated.

[0067] Another operating mode is to operate at least two columns in series. When the adsorbent in the first column is consumed, the first column is isolated and the spent adsorbent is either regenerated in situ or replaced with fresh adsorbent. The column is then brought back online in the last position, and so on. This operation is called the variable-sequence mode, or PRS, or variable-sequence reactor system, or "lead and lag." The combination of at least two adsorption columns makes it possible to overcome the potentially rapid poisoning and / or clogging of the adsorbent due to the combined action of metal contaminants, diolefins, gums derived from diolefins, and insoluble materials that may be present in the pyrolysis oil being treated. This is because the presence of at least two adsorption columns makes it easy to replace and / or regenerate the adsorbent, advantageously without shutting down the pretreatment unit and, indeed, without further process shutdown, thereby reducing the risk of clogging and thus avoiding unit shutdowns due to clogging, controlling costs, and limiting adsorbent consumption.

[0068] According to another variant, the optional pretreatment step a0) is carried out in a section for washing with an aqueous solution, for example water, or an acidic or basic solution. This washing section can comprise equipment that allows the feedstock to be brought into contact with the aqueous solution and for the phase separation to obtain, on the one hand, the pretreated feedstock and, on the other hand, an aqueous solution containing impurities. These equipment can comprise, for example, stirred reactors, settlers, mixer-settlers and / or cocurrent or countercurrent washing columns.

[0069] According to another variant, the optional pretreatment step a0) is carried out by filtration. The filtration step makes it possible to remove inorganic solids, sediments and / or fine particles contained in the feedstock, in particular metals, metal oxides and metal chlorides. Generally, filters are used, the pore size (e.g., diameter or equivalent diameter) of which is less than 25 μm, preferably less than 10 μm, and even more preferably less than 5 μm. According to another variant, filters with pore sizes less than 25 μm but greater than 5 μm can also be used. It is also possible to use a series of filters with different pore sizes, in particular a series of filters with pore sizes decreasing in the direction of circulation of the feedstock. These filtration media are well known for industrial use. For example, cartridge filters or self-cleaning filters are suitable. The solids content can be measured, for example, by the heptane insolubles test, ASTM D-3279 method. The content of insolubles in heptane must be reduced to less than 0.5% by weight, preferably less than 0.1% by weight.

[0070] According to a particular embodiment, step a0) of pretreatment by filtration comprises at least one filter whose pore size is less than 10 μm, preferably more than 5 μm, optionally followed by a filtration system whose pore size is less than 2 μm, preferably less than 1 μm.

[0071] According to another particular embodiment, step a0) of pretreatment by filtration comprises at least one filter whose pore size is less than 10 μm, preferably greater than 5 μm, followed by an electrostatic precipitation system.

[0072] According to another particular embodiment, step a0) of pretreatment by filtration comprises at least one filter whose pore size is less than 10 μm, preferably greater than 5 μm, followed by a system of one or more filters using a filtration adjuvant such as sand or diatomaceous earth.

[0073] According to another variant, said optional pretreatment step a0) is carried out by centrifugation. According to another variant, the pretreatment step a0) comprises centrifugation and filtration.

[0074] According to another variant, said optional pretreatment step a0) is carried out by sedimentation. According to another variant, the pretreatment step a0) comprises sedimentation and filtration.

[0075] According to another variant, the optional pretreatment step a0) is carried out by gas stripping, thus reducing the oxygen content in the feedstock. Gas extraction can remove oxygen (O2) that may be dissolved in the feedstock, thus reducing the probability of free radical formation that leads to polymerization in downstream processes. This method generally involves contacting the feedstock with an extraction gas (e.g., H2, N2, or a mixture thereof), thus transferring at least a portion of the dissolved oxygen in the feedstock to the extraction gas, and subsequently separating the extraction gas from the feedstock. The ratio of the volume of the extraction gas to the volume of the feedstock (the two volumes measured under gas extraction conditions) is generally greater than 1, preferably at least 3. In certain embodiments, the extraction gas can contain at least 60% (mole percent) H2. Dissolved H2 remaining in the feedstock after the gas extraction step is not a problem for downstream hydroprocessing. Preferably, the gas extraction step is completed before any (pre)heating of the feedstock to minimize potential fouling.

[0076] Said optional pretreatment step a0) generally comprises one or more, preferably several, of the above-mentioned treatments. It may in particular comprise a series of aqueous washing and / or adsorption steps followed by a gas stripping step and a filtration and / or centrifugation step. All these steps are preferably carried out before any (pre)heating of the feedstock.

[0077] Said optional pretreatment step a0) therefore makes it possible to obtain a pretreated feedstock which is then fed to the hydrotreatment step a).

[0078] (Hydrotreatment step a)) According to the present invention, the method comprises step a) carried out in a hydrotreating reaction section comprising at least one hydrotreating catalyst, said hydrotreating reaction section being fed with a gas stream comprising at least a pyrolysis feedstock and hydrogen, said hydrotreating reaction section being operated at an average temperature of 100°C to 220°C, a hydrogen partial pressure of 1.0 to 3.0 MPa (absolute), and a hydrotreating time of 0.05 to 5 h. -1 The hydrogen coverage is calculated based on the volume (m 3 ) 5-50Nm of hydrogen per 3 to obtain a partially hydrotreated effluent having hydrocarbon compounds with reduced halogen content.

[0079] Step a) is in particular carried out under mild hydrogen pressure and temperature conditions which in particular allow the removal of halogens, in particular chlorine, making the pyrolysis oil suitable as a co-feed for downstream units, whilst preserving as much as possible the diolefins and olefins which can be upgraded in the FCC (for the production of propylene).

[0080] Other impurities contained in the pyrolysis oil (metals, silicon, nitrogen, etc.) are not necessarily completely removed during the process according to the invention, but the operating conditions make it possible to remove at least a portion of them. Step a) therefore mainly comprises hydrogenation reactions of halogenated compounds and, to a lesser extent, other hydrotreating reactions well known to those skilled in the art, in particular hydrogenation of aromatic compounds, hydrodesulfurization and hydrodenitrogenation, as well as hydrogenation of olefins and diolefins, provided that they are retained in the oil.

[0081] Said hydrotreating reaction section is advantageously operated at an average hydrotreating temperature (or WABT as defined below) of between 100°C and 220°C, preferably between 120°C and 200°C, a hydrogen partial pressure of between 1.0 and 3.0 MPa (absolute), preferably between 1.0 and 2.4 MPa (absolute), preferably between 1.2 and 2.2 MPa (absolute), and a hydrotreating time of between 0.1 and 5 h -1 , preferably 0.1 to 2 hours -1 , preferentially 0.1 to 1.0 h -1 The hydrogen coverage in step a) is advantageously determined by the volume (m ) of fresh feedstock. 3 ) 5-50Nm of hydrogen per 3 , preferably the volume of fresh feedstock (m 3 ) 10-40Nm of hydrogen per 3 , preferably the volume of fresh feedstock (m 3 ) 15-30Nm of hydrogen per 3 is.

[0082] According to the invention, the "average temperature" of the reaction section corresponds to the weight average bed temperature (WABT), which is well known to those skilled in the art. The average temperature is advantageously determined as a function of the catalyst system used, the equipment and their configuration. The average temperature (or WABT) is calculated in the following way:

[0083]

number

[0084] In the formula, T inletis the temperature of the stream at the inlet of the reaction section, and T outlet is the temperature of the effluent at the outlet of the reaction section. Unless otherwise stated, the "average temperature" of the reaction section is given at the start of the cycle conditions.

[0085] Hourly space velocity (HSV) is defined herein as the ratio of the hourly volumetric flow rate of the feedstock, optionally including pretreated pyrolysis oil, to the volume of the catalyst(s).

[0086] The hydrogen coverage is defined as the ratio of the volumetric flow rate of hydrogen taken under standard temperature and pressure conditions relative to the volumetric flow rate of the "fresh" feedstock, i.e., the feedstock to be treated, possibly pretreated, at 15°C without taking into account the recycled fraction (volume (m) of feedstock). 3 ) standard volumetric flow rate of H2 per m 3 (Nm 3 (denoted as).

[0087] The hydrogen-containing gas stream fed to the hydrotreating reaction section can consist of hydrogen feed and / or recycled hydrogen. Preferably, an additional hydrogen-containing gas stream is advantageously introduced at the inlet of each reactor, in particular at the inlet of reactors operating in series, and / or at the inlet of each catalyst bed starting from the second catalyst bed of the reaction section. These additional gas streams are also called cooling streams. They make it possible to control the temperature in the reactors, where the reactions taking place are generally highly exothermic.

[0088] The hydrogen-containing gas stream may be derived from fossil or renewable sources, for example from the gasification of plastic waste, or may be produced by electrolysis.

[0089] Advantageously, the hydrogen-containing gas stream originates from a compressor used in the refinery and feeds another hydrogen-using hydrorefining unit, such as a hydrocracking, hydrotreating or hydroconversion unit. The hydrogen-containing gas stream originates from a compressor and can be used to feed, for example, a vacuum gas oil (VGO) hydrotreating unit. This has the advantage that a dedicated compressor for recycling hydrogen from step b) is not required, thus saving investment costs.

[0090] Optionally, the reaction section of step a) may also be fed with a portion of the partially hydrotreated hydrocarbon (recycle) effluent from step b), as described below.

[0091] Preferably, the process according to the invention comprises a hydrotreating step a) carried out in a hydrotreating reaction section using at least one fixed bed reactor having n catalyst beds, n being an integer greater than or equal to 1, preferably between 1 and 10, preferably between 2 and 5, each containing at least one hydrotreating catalyst.

[0092] The hydrotreating reaction section is advantageously fed with a gas stream comprising optionally pretreated pyrolysis feedstock and hydrogen in at least the first catalyst bed of the first reactor in operation, and it is also possible to inject at least a portion of the pyrolysis feedstock and / or at least a portion of the hydrogen between the various catalyst beds.

[0093] The hydrotreating reaction section, which employs at least one fixed bed reactor, can be operated with downflow or upflow of gas and liquid.

[0094] Advantageously, the reaction section of step a) comprises 1 to 5 reactors, preferably 2 to 5 reactors, particularly preferably 2 reactors. The advantage of a hydrotreating reaction section comprising several reactors is that it optimizes the processing of the feedstock while reducing the risk of clogging one or more catalyst beds and thus making it possible to avoid unit shutdowns due to clogging.

[0095] According to this embodiment, the hydrotreating reaction section of step a) comprises two reactors operated in a variable-sequence mode, also known as PRS, i.e. variable-sequence reactor system, or "lead and lag." The combination of at least two reactors in PRS mode makes it possible to isolate one reactor, drain the spent catalyst, recharge the reactor with fresh catalyst, and return said reactor to operation without shutting down the process. PRS technology is described in particular in FR 2 681 871.

[0096] According to another embodiment, the hydrotreating reaction section comprises a single fixed bed reactor containing n catalyst beds, where n is an integer greater than or equal to 1, preferably between 1 and 10, suitably between 2 and 5.

[0097] Advantageously, reactor internals, for example of the filter plate type, can be used to prevent clogging of the reactor or reactors, an example of which is described in FR 3 051 375.

[0098] Preferably, step a) can use at least one guard bed upstream of the hydrotreating catalyst(s) containing an adsorbent material of the alumina, silica, silica-alumina, zeolite and / or activated carbon type, optionally containing a metal from group VIB and / or group VIII. Use may also be made of a series of guard beds with particles of different sizes, in particular with sizes decreasing (also called "grading") in the direction of flow of the feedstock.

[0099] Advantageously, said hydrotreating catalyst comprises a support, preferably a mineral support, and a hydrogenation-dehydrogenation functional element.

[0100] According to one variant, the hydrogenation-dehydrogenation functional elements comprise, in particular, at least one element from group VIII and at least one element from group VIB. The at least one element from group VIII is preferably chosen from nickel and cobalt, and the at least one element from group VIB is preferably chosen from molybdenum and tungsten. According to this variant, the total content of metal elements from groups VIB and VIII, expressed as oxides, is preferably between 1% and 40% by weight, preferentially between 5% and 30% by weight, relative to the total weight of the catalyst. When the metal is cobalt or nickel, the metal content is expressed as CoO and NiO, respectively. When the metal is molybdenum or tungsten, the metal content is expressed as MoO3 and WO3, respectively.

[0101] The weight ratio of the metal(s) from group VIB to the metal(s) from group VIII, expressed as metal oxides, is preferably 1-20, suitably 2-10.

[0102] According to this variant, the reaction section of step a) comprises a hydrotreating catalyst, for example, comprising 0.5% to 12% by weight of nickel, preferably 0.9% to 10% by weight of nickel (expressed as nickel oxide NiO relative to the weight of the catalyst), and 1% to 30% by weight of molybdenum, preferably 3% to 20% by weight of molybdenum (expressed as molybdenum oxide MoO3 relative to the weight of the catalyst), preferably on a mineral support, preferably an alumina support.

[0103] According to another variant, the hydrogenation-dehydrogenation functional element comprises, and preferably consists of, at least one element of group VIII, preferably nickel. According to this variant, the content of nickel oxide is preferably between 1% and 50% by weight, preferably between 10% and 30% by weight, relative to the weight of the catalyst. This type of catalyst is preferably used in its reduced form, preferably on a mineral support, preferably on an alumina support.

[0104] The support for the hydrotreating catalyst is preferably selected from alumina, silica, silica-alumina, magnesia, clay, and mixtures thereof. The support may contain a dopant compound, in particular an oxide selected from boron oxide, especially boron trioxide, zirconia, ceria, titanium oxide, phosphorus pentoxide, and mixtures of these oxides. Preferably, the hydrotreating catalyst comprises an alumina support, optionally doped with phosphorus and optionally boron. If phosphorus pentoxide 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. If boron trioxide B2O3 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 may be, for example, γ (gamma) or η (eta) alumina.

[0105] The hydrotreating catalyst is, for example, in the form of extrudates or in the form of beads.

[0106] Highly preferably, step a) may employ at least one hydrotreating catalyst used in step a) which, in addition to the one or more hydrotreating catalysts described above, contains, on an alumina support, less than 1% by weight of nickel and at least 0.1% by weight of nickel, preferably 0.5% by weight of nickel, expressed as nickel oxide NiO, relative to the weight of the catalyst, and less than 5% by weight of molybdenum and at least 0.1% by weight of molybdenum, preferably 0.5% by weight of molybdenum, expressed as molybdenum oxide MoO3, relative to the weight of the catalyst. This catalyst, which is not highly loaded with metals, may preferably be placed upstream or downstream, preferably upstream, of the one or more hydrotreating catalysts described above.

[0107] The preparation of the catalyst for hydrotreating step a) is known and generally comprises the impregnation of a support with a Group VIII metal and a Group VIB metal, if present, and optionally phosphorus and / or boron, followed by drying and then optionally calcination. The catalyst of step a) may be a catalyst used in its reduced form, and therefore its preparation comprises a reduction step.

[0108] Before being used in the process steps, the catalyst is generally subjected to sulfurization to form active species. Depending on the content of sulfur compounds in the initial feedstock to be treated, a stream containing a sulfurizing agent can be injected upstream of the optional pretreatment step a0) or hydrotreating step a), preferably upstream of hydrotreating step a), to ensure a sufficient amount of sulfur to form the active species (sulfide form) of the catalyst. This activation or sulfurization step is carried out by methods well known to those skilled in the art, advantageously in a sulfo-reducing atmosphere in the presence of hydrogen and hydrogen sulfide. The sulfurizing agent is preferably a hydrocarbon fraction with a boiling point below 400°C containing H2S gas, elemental sulfur, CS2, mercaptans, sulfides and / or polysulfides, sulfur compounds with a view to sulfurizing the catalyst, or any other sulfur-containing compound used to activate the hydrocarbon feedstock. The sulfur-containing compound is advantageously selected from alkyl disulfides, such as dimethyl disulfide (DMDS), alkyl sulfides, such as dimethyl sulfide, thiols, such as n-butyl mercaptan (or 1-butanethiol), and polysulfide compounds of the tert-nonyl polysulfide type. The catalyst can also be sulfided by sulfur contained in the feedstock to be desulfurized. Preferably, the catalyst is sulfided in situ in the presence of a sulfiding agent and a hydrocarbon feedstock. Highly preferably, the catalyst is sulfided in situ in the presence of a feedstock to which dimethyl disulfide has been added. The sulfiding agent can be injected continuously.

[0109] The partially hydrotreated effluent obtained at the end of the hydrogenation step a) is preferably sent directly to the washing / separation step b).

[0110] (Separation step b)) According to the invention, the treatment process comprises a separation step b), which is advantageously carried out in at least one washing / separation section, to which is fed at least the partially hydrotreated effluent from step a) and the aqueous solution, and which obtains at least a gaseous effluent, an aqueous effluent and a partially hydrotreated hydrocarbon effluent.

[0111] This separation step b) makes it possible in particular to remove halogens (chlorine) in the form of hydrogen halides (in particular HCl) formed by reaction of the hydrogen ions released by the hydrogenation of the halogenated compound in step a) dissolved in aqueous solution with the halide ions.

[0112] The separation step b) is advantageously carried out at a temperature between 20° C. and 200° C., preferentially between 50° C. and 180° C., and preferably between 80° C. and 150° C. Advantageously, the separation step b) is carried out at a pressure close to that used in steps a) and / or b), preferably between 1.0 and 2.0 MPa, in order to facilitate the recycling of hydrogen.

[0113] The separation step can advantageously be carried out by any method known to those skilled in the art, such as a combination of one or more separators (drums) and / or one or more stripping columns, to which or these separators (drums) and / or columns a stripping gas, for example a hydrogen-rich gas stream, can optionally be fed. The washing / separation section of step c) can be made up, at least in part, of common or separate washing and separation equipment.

[0114] Advantageously, separation step b) comprises injecting an aqueous solution, preferably water, into the partially hydrotreated effluent from step a) upstream of the washing / separation section, to dissolve some, and preferably all, of the hydrogen halide (in particular HCl) and any salts present.

[0115] The aqueous solution may be water. It may also be a basic aqueous solution (for example, by adding NaOH). The use of a basic solution makes it possible to neutralize the hydrogen halide and any dissolved salts.

[0116] In one optional embodiment of the present invention, separation step b) comprises the injection of an aqueous solution into the partially hydrotreated effluent from step a), followed by a scrubbing / separation section, which advantageously comprises separate phases, obtaining at least one aqueous effluent laden with hydrogen halide (especially HCl) and any dissolved salts present, a scrubbed partially hydrotreated effluent, and a partially washed gaseous effluent. The aqueous effluent and the scrubbed partially hydrotreated effluent can then be separated in a knockout drum, obtaining the scrubbed partially hydrotreated effluent and the aqueous effluent. The partially washed gaseous effluent can simultaneously be introduced into a scrubbing column, where it flows countercurrently against an aqueous stream, preferably an aqueous stream of the same nature as the aqueous solution injected into the partially hydrotreated effluent, thereby removing at least part, preferably all, of the hydrochloric acid contained in the partially washed gaseous effluent and thus obtaining the gaseous effluent, preferably essentially comprising hydrogen, and an acidic aqueous stream. The aqueous effluent from the knock-out drum can optionally be mixed with the acidic aqueous stream and can be used, optionally as a mixture with the acidic aqueous stream, to feed the aqueous solution and / or the wash column upstream of the washing / separation section of separation step c) in a water recycle circuit, which can include a supply of water and / or a basic solution and / or a discharge allowing impurities to be discharged.

[0117] The hydrotreating step a) mainly involves hydrogenation reactions of halogenated compounds and, to a lesser extent, also other hydrotreating reactions such as hydrodenitrogenation, which is the hydrogenation of nitrogen compounds to give NH3, and hydrodesulfurization, which is the hydrogenation of sulfur compounds to give H2S.

[0118] If NH3 is present in the partially hydrotreated effluent from step a), separation step b) also makes it possible to remove ammonium chloride salts formed in particular by reaction between chloride ions released in the form of HCl by the hydrogenation of chlorinated compounds during step a) and ammonium ions generated in the form of NH3 by the hydrogenation of nitrogen compounds during step a), by dissolving them in aqueous solution.

[0119] If H2S is present in the partially hydrotreated effluent from step a), separation step b) also makes it possible to remove the ammonium sulfide ((NH4)2S) salts formed by the reaction between H2S resulting from the hydrodesulfurization of sulfur compounds and NH3, by dissolving them in aqueous solution.

[0120] According to one embodiment, depending on the content of chlorine compounds in the initial or pretreated feedstock, a stream containing nitrogen compounds such as ammonia or amines, for example monoethanolamine, diethanolamine and / or monodiethanolamine, can be injected upstream of the hydrotreating step a) to ensure a sufficient amount of ammonium ions to combine with the chloride ions formed during the hydrotreating step in the form of ammonium chloride salts, thus making it possible to limit the formation of hydrochloric acid and therefore corrosion downstream of the separation section.

[0121] The gaseous effluent obtained at the end of step b) advantageously comprises hydrogen, preferably at least 80% by volume, preferably at least 85% by volume of hydrogen. The gaseous effluent obtained at the end of step b) contains very small amounts of chlorine, generally with a chlorine content of less than 5 ppm by weight, which makes it possible to send it to a purification unit that requires hydrogen.

[0122] According to one embodiment, the gaseous effluent can be at least partially recycled to the hydrotreatment step a), the recycling system being able to include a purification section (e.g. for adsorption of heavy metals such as mercury).

[0123] According to another preferred embodiment, the gaseous effluent can be at least partially recycled upstream of the hydrogen compressor used to feed the hydrogen-using hydrorefining units of the refinery, such as hydrocracking, hydrotreating or hydroconversion units. The gaseous effluent can in particular be recycled upstream of the compressor used to feed the vacuum gas oil hydrotreating unit. This has the advantage that a dedicated compressor for recycling hydrogen from step b) is not required, thus saving investment costs.

[0124] With regard to the partially hydrotreated hydrocarbon liquid effluent from step b), according to one variant, part of the partially hydrotreated hydrocarbon effluent from step b) can be recycled upstream of step a). Recycling part of the partially hydrotreated hydrocarbon effluent from step b) to step a) or upstream of step a) advantageously makes it possible, on the one hand, to dilute impurities and, on the other hand, to control the temperature in step a), in which the reactions involved may be highly exothermic. Diluting the impurities makes it possible to limit undesirable reactions such as the polymerization of diolefins (gum formation) and / or coke formation.

[0125] Advantageously, the recycled amount of the partially hydrotreated hydrocarbon effluent from step b), i.e., the recycled proportion of the product obtained, is adjusted so that the weight ratio of the recycle stream from step b) to the pyrolysis oil-containing feedstock, i.e., the feedstock to be treated and fed to the entire process, is not more than 10, preferably not more than 7, and preferentially not less than 0.001, preferably not less than 0.01, and suitably not less than 0.1. Preferably, the amount of recycled partially hydrotreated hydrocarbon effluent from step b) is adjusted so that the weight ratio of the recycle stream to the pyrolysis oil-containing feedstock is between 0.01 and 10, preferably between 0.1 and 7, and particularly preferably between 0.2 and 5. This recycle rate makes it possible to control the temperature increase in particular in step a), since a high recycle rate leads to a high feedstock dilution rate, which makes it possible to control the temperature increase at the start of the reaction section of step a) by the dilution effect. The injection of the partially hydrotreated hydrocarbon effluent from step b) can take place in the first catalyst bed of the reaction section of step a) or between the various catalyst beds. If the hydrotreating reaction section of step a) comprises two reactors operating in a sequence-variable mode, at least a portion of the partially hydrotreated hydrocarbon effluent from step b) can be recycled between the two reactors.

[0126] According to another preferred embodiment, the partially hydrotreated hydrocarbon effluent from step b) is partially, preferably completely, sent directly as co-feed to the inlet of a refinery unit, such as an FCC unit, or to a hydrogen-using unit, such as a hydrocracking, hydrotreating or hydroconversion unit, which has the advantage that no recycle compressor is required.

[0127] Said partially hydrotreated hydrocarbon effluent from step b) thus obtained by treatment according to steps a) and b) of the process of the present invention has a composition suitable for being introduced as co-feed together with petroleum feedstocks and / or biomass-derived feedstocks into an FCC unit or a hydrorefining unit.

[0128] The partially hydrotreated hydrocarbon effluent from step b) is in particular an effluent having a reduced content of halogenated compounds, in particular chlorine.

[0129] Preferably, at least 50%, more preferably at least 75%, of the halogenated compounds in the initial feedstock are removed during steps a) and b).

[0130] Preferably, at least 80%, more preferentially at least 90% of the olefins are retained during step a).

[0131] Preferably, at least 25% and more preferentially at least 40% of the diolefins are retained during step a).

[0132] Other impurities contained in the pyrolysis oil (metals, silicon, nitrogen, etc.) are not necessarily completely removed during steps a) and b) of the method according to the invention, but the operating conditions make it possible to remove at least a portion of them. In particular, the pyrolysis oil, which is a partially hydrotreated hydrocarbon effluent, does not need to be completely hydrotreated to be able to be introduced into downstream FCC refining or hydrorefining units, and it does not need to undergo further hydrotreatment, particularly at higher temperatures and / or pressures, before being introduced into the downstream units. The remaining impurities can be converted or removed in downstream units, and the remaining content of impurities is compatible with these units.

[0133] Preferably, at least 50%, more preferentially at least 75% of the metal elements in the initial feedstock are removed during steps a) and b).

[0134] Generally, up to 50%, more preferentially up to 25%, of the sulfur compounds in the initial feedstock are removed during steps a) and b).

[0135] Preferably, at least 25%, more preferentially at least 50% of the oxygenates in the initial feedstock are removed during steps a) and b).

[0136] Generally, up to 30%, more preferentially up to 15%, of the nitrogen compounds in the initial feedstock are removed during steps a) and b).

[0137] The content of heavy metals such as mercury, arsenic, zinc and lead remains essentially unchanged.

[0138] The content is given as the relative concentration by weight, percentage by weight (%), parts by million by weight (ppm) or parts by billion by weight (ppb) of the total weight of the stream under consideration.

[0139] (Step c): FCC or hydrorefining) According to the invention, the process comprises a step c) of fluid catalytic cracking or hydrorefining of a petroleum feedstock and / or a feedstock resulting from biomass conversion, in which at least part of the partially hydrotreated hydrocarbon effluent from step b) is introduced as a co-feed, said partially hydrotreated hydrocarbon effluent from step b) being introduced without first undergoing another hydrotreatment step carried out at a temperature and / or pressure higher than that of step a), said mixture of said petroleum feedstock and / or said feedstock resulting from biomass conversion and the partially hydrotreated hydrocarbon effluent from step b) having a halogen content of less than or equal to 10 ppm by weight.

[0140] Due to the hydrotreating step a) which makes it possible to release the halogenated compounds (e.g. chlorine) mainly in gaseous form (especially hydrogen halides of HCl type), followed by the washing / separation step b) which makes it possible to dissolve and remove the hydrogen halides, the partially hydrotreated hydrocarbon effluent from step b) has a sufficiently reduced halogenated compounds content that it can be injected as a co-feed into a unit for fluidized bed cracking, hydrocracking, hydrotreating or hydroconversion of petroleum feedstocks and / or feedstocks resulting from biomass conversion.

[0141] In fact, it is chlorine that is generally the limiting contaminant when processing pyrolysis oil in existing units: even at low concentrations (<10 ppm by weight, or even <5 ppm by weight), chlorine is a cause of corrosion (in the form of HCl) that can occur in existing units, the metallurgy of which is generally not designed to withstand chlorine levels above 10 ppm by weight, or even above 5 ppm by weight, in the feedstock.

[0142] The partially hydrotreated hydrocarbon effluent from step b) is introduced into a unit for fluid catalytic cracking or hydrorefining of a petroleum feedstock and / or a feedstock resulting from the biomass conversion in an amount such that the content of chlorine in the mixture of the petroleum feedstock and / or the feedstock resulting from the biomass conversion and the partially hydrotreated hydrocarbon effluent from step b) is not more than 10 ppm by weight, preferably not more than 5 ppm by weight.

[0143] Generally, in the process according to the invention, the weight ratio of the flow rate of the partially hydrotreated hydrocarbon effluent (pyrolysis oil) from step b) to the flow rate of the petroleum feedstock and / or feedstock resulting from biomass conversion introduced into the unit of step c) is generally less than 1, preferably between 0.01 and 0.9, preferably between 0.02 and 0.5.

[0144] If the content of halogenated compounds in the partially hydrotreated hydrocarbon effluent from step b) is more than 10 ppm by weight, or even more than 5 ppm by weight, a chlorine content of 10 ppm or even 5 ppm can be achieved at the inlet of the unit by dilution with petroleum feedstock and / or feedstock resulting from biomass conversion.

[0145] During step c), the partially hydrotreated effluent from step b) is introduced as co-feed together with a petroleum feedstock and / or a feedstock resulting from biomass conversion into a fluid catalytic cracking unit or a hydrogen-based hydrorefining unit, such as a hydrotreating, hydrocracking or hydroconversion unit. Preferably, the partially hydrotreated effluent from step b) is injected as co-feed into the fluid catalytic cracking unit.

[0146] The petroleum feedstock used in the fluid catalytic cracking unit or the hydrorefining unit may be selected from gasoline, gas oil, vacuum gas oil, atmospheric residue, vacuum residue, atmospheric distillate, vacuum distillate, heavy fuel oil, oil, wax and paraffin, waste oil, deasphalted residue or crude oil, petroleum feedstocks derived from thermal or catalytic conversion processes, or mixtures of such feedstocks.

[0147] The biomass-derived feedstock used in the fluid catalytic cracking unit or the hydrorefining unit can be selected from vegetable oils, oils from algae or algae oils, fish oils, waste edible oils, and fats of vegetable or animal origin; fatty acid methyl esters of vegetable and / or animal origin, fatty acid methyl esters from waste edible vegetable oils, feedstocks derived from thermal or catalytic biomass conversion processes, or mixtures of such feedstocks, in particular feedstocks as described in the pyrolysis oil feedstock section above.

[0148] (FCC) The fluid catalytic cracking (FCC) process is widely used in the refining industry to convert atmospheric gas oil, vacuum gas oil, and atmospheric residual oil, lignocellulosic feedstocks, or more commonly biomass-derived feedstocks, used alone or in mixtures, into high-octane gasoline, light fuel oil, heavy fuel oil, light gases rich in olefins (propylene, butylene), and coke. FCC units use highly active zeolite catalysts to crack heavy hydrocarbon molecules. Conventional FCC units are used. For example, a general description of catalytic cracking (the first industrial use of fluidized-bed catalysts dates back to 1936 (Houdry process) or 1942) can be found in Ullmann's Encyclopedia of Industrial Chemistry, Volume A 18, 1991, pages 61 to 64. The choice of catalyst and operating conditions depends on the products desired depending on the feedstock being treated, as described, for example, in the article by M. Marcilly, published in Revue de l'Institut Francais du Pétrole, Nov.-Dec. 1975, pages 990-991, pages 969-1006.

[0149] The fluid catalytic cracking step c) is generally carried out in a substantially vertical reactor in either an upflow (riser) or downflow (downer) mode in the fluid catalytic cracking reaction section, in the presence of a feedstock selected from atmospheric gas oil, vacuum gas oil, atmospheric resid and feedstocks derived from biomass and a zeolite catalyst, at a reactor temperature of 450°C to 600°C, with a contact time in the reactor of less than 1 minute, often 0.1 to 50 seconds.

[0150] Conventional zeolite catalysts containing a matrix, optionally an additive, and at least one zeolite are typically used in FCC processes. The amount of zeolite varies, but is usually 3% to 60%, often 6% to 50%, and most often 10% to 45% by weight of the catalyst. The zeolite is usually dispersed in the matrix. The amount of additive is usually 0% to 30%, often 0% to 20%, by weight of the catalyst. The amount of matrix represents the balance to 100% by weight. The additive is generally selected from the group formed by oxides of metals from Group IIa of the Periodic Table of Elements, such as magnesium oxide or calcium oxide, rare earth metal oxides, and titanates of metals from Group IIa. The matrix is ​​generally silica, alumina, silica-alumina, silica-magnesia, clay, or a mixture of two or more of these products. The most commonly used zeolite is zeolite Y.

[0151] (hydrogenation refinement) Hydrorefining processes that use hydrogen to hydrorefining petroleum feedstocks and / or feedstocks resulting from biomass conversion are known to those skilled in the art and include processes such as hydrotreating, hydrocracking, or hydroconversion. (hydrotreating) The term "hydrotreating," commonly referred to as "HDT," refers to an operation whose primary objective is to remove impurities such as sulfur, nitrogen, oxygen, halides, and trace metals from a feedstock, saturate olefins, and / or stabilize hydrocarbon free radicals by reacting the hydrocarbons with hydrogen rather than with themselves. The primary objective is to maintain the boiling range of the feedstock. Hydrotreating, therefore, includes, among others, hydrodesulfurization (commonly known as "HDS"), hydrodenitrogenation (commonly known as "HDN"), and hydrodemetalization (commonly known as "HDM") reactions, along with hydrogenation, hydrodeoxygenation (commonly known as "HDO"), hydrodearomatization, hydroisomerization, and hydrodealkylation reactions. Hydrotreating is typically carried out using fixed-bed reactors, although other reactors, such as ebullated-bed hydrotreating reactors, can also be used for hydrotreating.

[0152] The feedstocks used in hydroprocessing processes are, for example, gasoline, gas oil, vacuum gas oil, atmospheric residue, vacuum residue, atmospheric distillate, vacuum distillate, heavy fuel oil, oil, wax and paraffin, waste oil, deasphalted residue or crude oil, feedstocks derived from thermal or catalytic conversion processes, lignocellulosic feedstocks or more generally feedstocks derived from biomass, employed alone or as a mixture. The feedstocks to be treated, in particular the above-mentioned feedstocks, generally contain heteroatoms such as sulfur, oxygen and nitrogen, and in the case of heavy feedstocks, they usually also contain metals.

[0153] Hydrotreatment processes particularly suitable for introducing pyrolysis oil partially hydrotreated according to the process according to the invention are processes for hydrotreating vacuum gas oil, diesel, kerosene or gasoline feedstocks and / or feedstocks derived from biomass selected from vegetable oils, oils from algae or algal oils, fish oils, waste cooking oils and fats of plant or animal origin.

[0154] The operating conditions used in the process for carrying out the reaction for hydrotreating the above-mentioned feedstock are generally as follows: the average temperature is advantageously between 180°C and 450°C, preferably between 250°C and 440°C, the pressure is advantageously between 0.5 and 30 MPa, preferably between 1 and 18 MPa, and the hourly space velocity is advantageously between 0.1 and 20 h -1 , preferably 0.2 to 5 hours -1 and the hydrogen coverage is the ratio of the volume of the feedstock (m 3 ) 50-5000Nm of hydrogen per 3 , preferably 80 to 2000 Nm 3 The definitions of average temperature (WABT), HSV and hydrogen coverage correspond to those above.

[0155] Conventional hydrotreating catalysts generally comprise an oxide support and an active phase based on metals of groups VIB and VIII in the form of their oxides, and also contain phosphorus. The group VIB metals present in the active phase of the catalyst are preferentially selected from molybdenum and tungsten. The group VIII metals present in the active phase of the catalyst are preferentially selected from cobalt, nickel and mixtures of these two elements. The active phase of the catalyst is preferably selected from the group formed by the element combinations nickel-molybdenum, cobalt-molybdenum, nickel-tungsten, nickel-molybdenum-tungsten and nickel-cobalt-molybdenum, and highly preferably the active phase consists of a combination of cobalt and molybdenum, nickel and molybdenum, nickel and tungsten or nickel-molybdenum-tungsten.

[0156] The content of the Group VIII metal, expressed as the oxide of the Group VIII metal, relative to the total weight of the catalyst, is 1% to 10% by weight, preferably 1.5% to 9% by weight, more preferably 2% to 8% by weight. The content of the Group VIB metal, expressed as the oxide of the Group VIB metal, relative to the total weight of the catalyst, is 1% to 40% by weight, preferably 1% to 35% by weight, more preferably 2% to 30% by weight. The molar ratio of the Group VIII metal to the Group VIB metal in the fresh catalyst is generally 0.1 to 0.8, preferably 0.15 to 0.6.

[0157] Optionally, the hydrotreating catalyst may further exhibit a phosphorus content, relative to the total weight of the fresh catalyst, generally between 0.1% and 20% by weight of P2O5, preferably between 0.2% and 15% by weight of P2O5, and highly preferably between 0.3% and 11% by weight of P2O5. Furthermore, the phosphorus / (Group VIB metal) molar ratio is generally between 0.08 and 1, preferably between 0.1 and 0.9, and highly preferably between 0.15 and 0.8.

[0158] The oxide support of the hydrotreating catalyst is usually a porous solid selected from the group consisting of alumina, silica, silica-alumina or oxides of titanium and magnesium, used alone or in a mixture with alumina or silica-alumina. According to a particularly preferred alternative form, the oxide support consists of alumina, silica or silica-alumina.

[0159] The catalyst may further contain at least one organic compound containing oxygen and / or nitrogen and / or sulfur prior to sulfurization. Such additives are known. Typically, the organic compound is selected from compounds containing one or more chemical functional groups selected from carboxylic acid, alcohol, thiol, thioether, sulfone, sulfoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea, and amide functional groups, or compounds containing a furan ring, or sugars. The content of the one or more organic compounds containing oxygen and / or nitrogen and / or sulfur on the catalyst is 1% to 30% by weight, preferably 1.5% to 25% by weight, and more preferably 2% to 20% by weight, relative to the total weight of the catalyst.

[0160] (hydrocracking) The hydrocracking process makes it possible to convert petroleum fractions, especially vacuum distillates (VD), into lighter, more upgradeable products (gasoline, middle distillates). Other reactions such as hydrogenation of olefins or aromatics, hydrodemetallization, hydrodesulfurization, hydrodenitrogenation can also be carried out.

[0161] Hydrocracking is typically carried out using a fixed bed reactor.

[0162] The feedstock used in hydrocracking processes is generally a hydrocarbon feedstock in which at least 50% by weight of the compounds have an initial boiling point above 300°C and a final boiling point below 650°C. It can be selected from HCO (heavy cycle oil (heavy gas oil produced from a catalytic cracking unit)), vacuum distillates, e.g., gas oils resulting from direct distillation of crude oil or from conversion units such as catalytic cracking units, cokers, or visbreaking units; aromatic compounds; feedstocks derived from units for the extraction of lubricant base stocks or from solvent dewaxing of lubricant base stocks; distillates derived from processes for fixed-bed or ebullated-bed desulfurization or hydroconversion of atmospheric and / or vacuum residues and / or deasphalted oils; or the feedstock can be deasphalted oil, contain vegetable oils, or be derived from the conversion of biomass-derived feedstocks. It can also be paraffins from a Fischer-Tropsch process. The hydrocarbon feedstock processed according to the hydrocracking process of the present invention can also be a mixture of the above feedstocks. Preferably, the feedstock is a vacuum distillate.

[0163] Hydrocracking processes particularly suitable for introducing pyrolysis oil partially hydrotreated according to the process according to the invention are processes for hydrotreating vacuum gas oil feedstocks.

[0164] The hydrocracking process is generally carried out at an average temperature of 250°C to 480°C, advantageously 320°C to 450°C, preferably 330°C to 435°C, under a pressure of 2 to 25 MPa, preferably 3 to 20 MPa, and the hourly space velocity (HSV) of the feedstock relative to the volume of each catalyst is advantageously 0.1 to 40 h -1 , preferably 0.2 to 12 hours -1 , preferably 0.4 to 6 hours -1 and the hydrogen coverage is the ratio of the volume of the feedstock (m 3 ) 50-5000Nm of hydrogen per 3 , preferably 100 to 2000 Nm 3 The definitions of average temperature (WABT), HSV and hydrogen coverage correspond to those above.

[0165] Processes for the hydrocracking of vacuum distillates encompass a range of pressures and conversions, from mild hydrocracking to high-pressure hydrocracking, where mild hydrocracking is understood to mean hydrocracking resulting in moderate conversions, generally less than 40%, and operating at low pressures, generally between 2 MPa and 6 MPa.

[0166] Hydrocracking processes can be "one-step" hydrocracking processes or "two-step" hydrocracking processes. "One-step" hydrocracking processes generally involve a first, exhaustive hydrotreatment, the purpose of which is to carry out exhaustive HDN, exhaustive HDS, and exhaustive HDA of the feedstock before it is passed over one or more hydrocracking catalysts. "Two-step" hydrocracking processes involve a first step, the purpose of which is to carry out hydrotreating of the feedstock, as in the "one-step" process, but also to achieve a feedstock conversion of typically around 40% to 60%. The effluent from the first step is then subjected to a separation, generally by distillation, most often referred to as intermediate separation, the purpose of which is to separate the converted product from the unconverted portion. In the second step of the two-step hydrocracking process according to the invention, only the portion of the feedstock not converted during the first step is processed.

[0167] Hydrocracking catalysts are of the bifunctional type: they combine an acid function with a hydrogenation / dehydrogenation function. The acid function has a surface area of ​​generally 150-800 m 2 .g -1The hydrogenation / dehydrogenation function is provided by a porous support exhibiting surface acidity, such as halogenated (especially chlorinated or fluorinated) alumina, combinations of boron and aluminum oxides, amorphous or crystalline mesoporous aluminosilicates, and zeolites dispersed in an oxide binder. The hydrogenation / dehydrogenation function is provided by the presence of an active phase based on at least one metal from Group VIB and optionally at least one metal from Group VIII of the Periodic Table of the Elements. The most common formulations are the nickel-molybdenum (NiMo) and nickel-tungsten (NiW) types, and more rarely the cobalt-molybdenum (CoMo) type.

[0168] The metal content is as described for hydrotreating catalysts generally.

[0169] The hydrocracking catalyst may contain phosphorus and / or oxygen and / or nitrogen and / or sulfur containing organic compounds in the contents described for the hydrotreating catalyst.

[0170] (hydroconversion) The term "hydroconversion" refers to a process in which the primary objective is to reduce the boiling point range of a feedstock containing at least 50% of the heavy hydrocarbon fraction having a boiling point of at least 300° C. or at least 450° C., and a significant portion of the feedstock is converted to products having boiling ranges lower than that of the starting feedstock. Hydroconversion generally involves the fragmentation of larger hydrocarbon molecules to give smaller molecular fragments having fewer carbon atoms and higher hydrogen-to-carbon ratios.

[0171] The feedstock used in the hydroconversion process is generally a heavy hydrocarbon fraction containing at least 50% by weight of a portion having a boiling temperature of at least 300°C, preferably at least 350°C, even more preferably at least 375°C. Advantageously, the heavy hydrocarbon fraction of the feedstock consists of one or more vacuum residues. Vacuum residues can be obtained directly from crude oil or from other refinery units, such as residue hydrotreating, residue hydrocracking or residue visbreaking, among others. Preferably, the vacuum residue is a vacuum residue resulting from a vacuum distillation column of the first (straight run (SR)) fraction of crude oil.

[0172] The heavy hydrocarbon fraction of the feedstock may also consist of an aromatic fraction extracted from a unit for the production of lubricants, a deasphalted oil resulting from a deasphalting unit (dearasphalting unit raffinate), or an asphalt resulting from a deasphalting unit (dearasphalting unit bottoms).

[0173] The heavy hydrocarbon fraction of the feedstock may consist of sink or recycle oil (typically having a boiling range of 360°C to 550°C), FCC fluid catalytic cracking effluent, such as heavy cycle oil (HCO) or slurry oil (SLO).

[0174] The heavy hydrocarbon fraction may comprise or consist of at least one of the following feedstocks, alone or in mixture: crude oil, topped crude oil, atmospheric or vacuum residue from atmospheric or vacuum distillation (preferably from the first fractionation of crude oil), atmospheric or vacuum residue from atmospheric or vacuum distillation obtained during a direct coal liquefaction process, preferably a vacuum residue resulting from the vacuum distillation of crude oil (preferably from the first fractionation of crude oil).

[0175] Particularly suitable hydroconversion processes for introducing pyrolysis oil partially hydrotreated according to the process according to the invention are processes for the hydroconversion of vacuum resid feedstocks.

[0176] The hydroconversion process is generally carried out at an average temperature of between 340°C and 550°C, more preferentially between 350°C and 500°C, preferably between 360°C and 450°C, under a pressure of between 2 and 38 MPa, more preferentially between 5 and 25 MPa, even more preferably between 6 and 20 MPa, with an hourly space velocity (HSV) of the feedstock, relative to the volume of each catalyst, advantageously between 0.05 and 10 h -1 , preferably 0.1 to 5 hours -1 , more preferably 0.15 to 2 h -1 , and even more preferably 0.15 to 1 hour -1 and the hydrogen coverage is the ratio of the volume of the feedstock (m 3 ) 50-5000Nm of hydrogen per 3 , preferably 100 to 2000 Nm 3 , preferably 200 to 1000 Nm 3 The definitions of average temperature (WABT), HSV and hydrogen coverage correspond to those above.

[0177] The hydroconversion section may comprise one or more ebullated bed or hybrid bed (ebullated and entrained bed) reactors containing at least one supported hydroconversion catalyst, the reactors being arranged in series and / or in parallel, as used in the H-Oil® process, as described, for example, in patents US 4,521,295 or US 4,495,060 or US 4,457,831 or US 4,354,852, in the AIChE paper (March 19-23, 1995), Houston, Texas, paper number 46d, "Second generation ebullated bed technology", or in "Hydroprocessing and Hydroconversion of Residue Fractions", of the work "Catalysis by Transition Metal Sulphides".

[0178] The hydroconversion section may include one or more entrained bed reactors, also known as "slurry" reactors (reactors having three phases, i.e., liquid, gas, and solid, where the solid and liquid phases can behave as homogeneous phases) or alternatively fixed bed reactors (three-phase reactors in which the liquid feedstock flows downwardly over a fixed bed of supported catalyst; hydrogen typically co-flows with the liquid, but in some cases may flow counter-currently).

[0179] The hydroconversion catalyst generally comprises an alumina support, at least one Group VIII metal selected from nickel and cobalt, preferably nickel, and at least one Group VIB metal selected from molybdenum and tungsten, preferably molybdenum. Preferably, the hydroconversion catalyst comprises nickel as the Group VIII element and molybdenum as the Group VIB element.

[0180] The metal content is generally as described for hydrotreating catalysts.

[0181] The hydroconversion catalyst may contain phosphorus, and / or oxygen and / or nitrogen and / or sulfur containing organic compounds in the contents described for the hydrotreating catalyst.

[0182] (Analysis methods used) The analytical methods and / or specifications used to determine the characteristics of the various streams, in particular the feedstock and effluent streams to be treated, are known to those skilled in the art and are specifically listed below in Table 1 for information purposes. Other methods that are said to be equivalent, in particular equivalent IP, EN or ISO methods, can also be used.

[0183] [Table 1]

[0184] (1)The MAV method is described in the paper C. Lopez-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.

[0185] (List of drawings) The details of the elements referenced in Figures 1-2 will enable a better understanding of the present invention, but the present invention is not limited to the specific embodiments shown in Figures 1-2. The various embodiments presented can be used alone or in combination with each other, and there are no limitations on the combinations.

[0186] FIG. 1 represents a diagram of a general embodiment of the method of the present invention, comprising the following steps: - step a): hydrotreating the pyrolysis oil (1) in the presence of a hydrogen-rich gas (2) and optionally an amine provided by stream (3) and optionally a sulfiding agent provided by stream (4); - separation / washing step b); the partially hydrotreated effluent (5) from the hydrotreatment step a) is fed in the presence of an aqueous solution (6); at least a gaseous effluent (7), an aqueous effluent (8) and a partially hydrotreated hydrocarbon effluent (9) are obtained; a part (9a) of the hydrocarbon effluent (9) can be recycled to step a); - step c); fluid catalytic cracking or hydrorefining of a feedstock (10) resulting from the conversion of petroleum feedstock and / or biomass; introducing at least part, preferably all, of the partially hydrotreated hydrocarbon effluent (9) from step b) as co-feed, said partially hydrotreated hydrocarbon effluent (9) from step b) being introduced without a separate prior hydrotreatment step at higher temperature and / or pressure; increasing the yield of one or more products (11) resulting from step c), in particular propylene in the case of FCC.

[0187] Figure 2 represents a diagram of a particular embodiment of the process of the invention and is based on the diagram of Figure 1. This diagram shows the integration of the process according to the invention in an existing refinery, comprising the hydrotreatment of vacuum gas oil, followed by the separation of the hydrotreated vacuum gas oil and then its introduction into the FCC to produce, inter alia, gallins and olefins.

[0188] The hydrotreating step a) and the separation / washing step b) are carried out as described in FIG.

[0189] The vacuum gas oil (12) is introduced into a hydrotreating unit (13) in the presence of fresh hydrogen (14) pressurized by a compressor (15) to reach the required pressure. The compressor (15) is also fed with a gaseous effluent (7) essentially containing hydrogen resulting from separation step b) of the process according to the invention, possibly after a purification step (not shown).

[0190] The hydrogen-containing stream (2) fed to step a) of hydrotreating the pyrolysis oil in the process according to the invention can come from compressor (15), which makes it possible to use a single hydrogen compressor.

[0191] The hydrotreated effluent (16) is then subjected to separation (17) making it possible to recover at least a light fraction (18) (gas and naphtha), a middle fraction (19) (gas oil), and a hydrotreated vacuum gas oil fraction (10).

[0192] The hydrotreated vacuum gas oil cut (10) is then introduced into the catalytic cracking unit of step c) in admixture with the partially hydrotreated hydrocarbon effluent (9) from step b).

[0193] To allow a better understanding of the invention, only the main steps, together with the main flows, are shown in Figures 1 and 2. The presence of all equipment necessary for the operation (drums, pumps, exchangers, furnaces, columns, etc.) is clearly understood even though not shown. It is also understood that a hydrogen-rich gas stream (feed or recycle stream) can be injected at the inlet of each reactor or catalyst bed, or between two reactors or two catalyst beds, as described above.

[0194] (Example) The pyrolysis feedstock treated in this method is plastic pyrolysis oil (i.e., containing 100 wt. % of said plastic pyrolysis oil) having the characteristics indicated in Table 2.

[0195] [Table 2]

[0196] The pyrolysis feedstock is subjected to a hydrotreating step a), which is carried out in the presence of hydrogen and an alumina-supported NiMo hydrotreating catalyst in a fixed-bed reactor under different operating conditions as indicated in Table 3.

[0197] [Table 3]

[0198] At the end of the hydrogenation step a), the observed conversions (=(initial concentration-final concentration) / initial concentration) for chlorine, diolefins and olefins are given in Table 4.

[0199] [Table 4]

[0200] The effluent from the hydrotreating step a) is subjected to a separation step b), a stream of water is injected into the effluent from the hydrotreating step a), and the mixture is then treated in an acid gas washing column and a knockout drum.

[0201] The yields of the various fractions obtained after separation are shown in Table 5 (yields correspond to the ratio of the amounts by weight of the various products obtained relative to the weight of the upstream feedstock of step a), expressed as a percentage and indicated in % w / w).

[0202] [Table 5]

[0203] The characteristics of the liquid fraction obtained after separation step b) are shown in Table 6.

[0204] [Table 6]

[0205] The effluent from step b) is then mixed with an FCC grade petroleum feedstock having a chlorine content of 1 ppm by weight at a weight ratio of 10% oil / 90% petroleum feedstock to obtain a mixture containing less than 5 ppm by weight chlorine (for all examples), which can be introduced into a fluid catalytic cracking unit without fear of corrosion problems associated with the chlorine content.

[0206] However, in the cases of Examples 2 and 3 according to the invention, olefins and diolefins are retained, which is advantageous since they are compounds that can be upgraded in an FCC to produce propylene. Furthermore, the process according to the invention uses less energy (temperature in step a)) and less hydrogen (H consumption).

[0207] Example 3, carried out under very mild temperature and pressure conditions, shows that it is possible to obtain an oil that is fully stripped of chlorine while retaining as much of the olefins and diolefins as possible and using lower pressures (and therefore less energy) than Example 2. [Brief explanation of the drawings]

[0208] [Figure 1] 1 shows a diagram of a general embodiment of the method of the present invention. [Figure 2] 1 shows a diagram of a particular embodiment of the method of the invention, based on the diagram of FIG. 1.

Claims

1. 1. A method for treating a pyrolysis feedstock, the pyrolysis feedstock comprising pyrolysis oils of plastics and / or tires and / or solid recovered fuels containing halogenated compounds, the method comprising the steps of: a) A hydrotreating step carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst; the hydrotreating reaction section is fed with at least a pyrolysis feedstock and a gas stream containing hydrogen, the average temperature during the hydrotreating reaction section being 100°C to 220°C, the hydrogen partial pressure being 1.0 to 3.0 MPa (absolute), and the hourly space velocity being 0.05 to 5 h －１ and the hydrogen coverage is the volume (m ３ ) 5 to 50 Nm of hydrogen per ３ obtaining a partially hydrotreated effluent having hydrocarbon compounds with a reduced halogen content. b) a separation step of feeding the partially hydrotreated effluent from step a) and the aqueous solution to obtain at least a gaseous effluent, an aqueous effluent, and a partially hydrotreated hydrocarbon effluent; c) a step of fluid catalytic cracking or hydrorefining of a petroleum feedstock and / or a feedstock resulting from biomass conversion; introducing at least a portion of the partially hydrotreated hydrocarbon effluent from step b) as a co-feed; introducing said partially hydrotreated hydrocarbon effluent from step b) without first passing it through another hydrotreatment step carried out at a temperature and / or pressure higher than that of step a); said mixture of said feedstock resulting from petroleum feedstock and / or biomass conversion and the partially hydrotreated hydrocarbon effluent from step b) has a halogen content of not more than 10 ppm by weight.

2. 2. The method according to claim 1, wherein the weight ratio of the stream of partially hydrotreated hydrocarbon effluent from step b) to the stream of petroleum feedstock and / or feedstock resulting from biomass conversion introduced into step c) is less than 1.

3. 3. The method according to claim 1 or 2, wherein the pyrolysis feedstock consists of pyrolysis oil of plastics and / or tires and / or solid recovered fuels.

4. 4. The method according to claim 1, wherein the content of halogenated compounds in the pyrolysis feedstock is 1 to 5000 ppm by weight.

5. 5. The process according to claim 1, wherein a stream containing nitrogen and / or sulfur compounds is injected upstream of step a).

6. 6. The method according to claim 1, wherein the hydrotreating catalyst in step a) comprises a support selected from alumina, silica, silica-alumina, magnesia, clay and mixtures thereof, and a hydrogenation-dehydrogenation functional element comprising either at least one Group VIII element and at least one Group VIB element, or at least one Group VIII element.

7. 7. The method according to claim 1, comprising at least one step a0) of pretreating a feedstock comprising pyrolysis oil of plastics and / or tires and / or SRF, said pretreatment step being carried out upstream of step a), said pretreatment step comprising an adsorption step and / or a filtration step and / or a centrifugation step and / or a sedimentation step and / or an electrostatic separation step and / or a washing step with an aqueous solution and / or a gas stripping step.

8. 8. The method according to any one of claims 1 to 7, wherein the petroleum feedstock is selected from gasoline, gas oil, vacuum gas oil, atmospheric residue, vacuum residue, atmospheric distillate, vacuum distillate, heavy fuel oil, oil, wax and paraffin, waste oil, deasphalted residue or crude oil, petroleum feedstocks derived from thermal or catalytic conversion processes, or mixtures of such feedstocks.

9. 9. The method of any one of claims 1 to 8, wherein the biomass-derived feedstock is selected from vegetable oils, oils from algae or algal oils, fish oils, waste edible oils, and fats of vegetable or animal origin; fatty acid methyl esters of vegetable and / or animal origin, fatty acid methyl esters from waste edible vegetable oils, feedstocks derived from thermal or catalytic biomass conversion processes, or mixtures of such feedstocks.

10. 10. The process according to any one of claims 1 to 9, wherein the reaction section of step a) employs at least two reactors operating in a sequence-variable mode.

11. 11. The process according to any one of claims 1 to 10, wherein the fluid catalytic cracking step c) is carried out in a substantially vertical reactor in the fluid catalytic cracking reaction section, either in upflow mode or downflow mode, in the presence of a zeolite catalyst, at a reactor temperature of 450°C to 600°C, with a contact time in the reactor of less than 1 minute.

12. The hydrorefining step c) is a hydrotreating step carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst, wherein at least a hydrogen-containing gas stream is fed to the hydrotreating reaction section, the average temperature during the hydrotreating reaction section being between 180°C and 480°C, the hydrogen partial pressure being between 0.5 and 25 MPa (absolute), and the hourly space velocity being between 0.1 and 20 h －１ and the hydrogen coverage is the ratio of the volume of the feedstock (m ３ ) 50 to 5000 Nm of hydrogen per ３ The method according to any one of claims 1 to 10, wherein

13. The hydrorefining step c) is a hydrocracking step carried out in a hydrocracking reaction section containing at least one hydrocracking catalyst, to which a gas stream containing hydrogen is fed, the hydrocracking reaction section being operated at an average temperature of 250°C to 480°C, a hydrogen partial pressure of 2 to 25 MPa (absolute), and an hourly space velocity of 0.5 to 40 h －１ and the hydrogen coverage is the ratio of the volume of the feedstock (m ３ ) 80 to 5000 Nm of hydrogen per ３ The method according to any one of claims 1 to 10, wherein

14. The hydrorefining step c) is a hydroconversion step carried out in a hydroconversion reaction section containing at least one hydroconversion catalyst, wherein a gas stream containing hydrogen is fed to the hydroconversion reaction section, the average temperature during the hydroconversion reaction section being between 340°C and 550°C, the hydrogen partial pressure being between 2 and 38 MPa (absolute), and the hourly space velocity being between 0.05 and 10 h －１ and the hydrogen coverage is the ratio of the volume of the feedstock (m ３ ) 50 to 5000 Nm of hydrogen per ３ The method according to any one of claims 1 to 10, wherein

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