Method for treating pyrolysis oil from plastics and / or solid recovered fuels containing impurities

Abstract

The present invention relates to a method for treating pyrolysis oil from plastics and / or solid recovered fuels (SRF), comprising: a) an optional selective hydrogenation step of the feedstock; b) ebullated bed, entrained bed and / or moving bed hydroconversion to obtain a hydroconverted effluent; c) separation of the hydroconverted effluent in the presence of an aqueous stream to obtain a gaseous effluent, an aqueous liquid effluent and a hydrocarbon liquid effluent; d) fractionation of the hydrocarbon liquid effluent to obtain at least one gas stream, a fraction having a boiling point of 385°C or less and a fraction having a boiling point above 385°C; e) hydrotreatment of the fraction containing compounds having a boiling point of 385°C or less to obtain a hydrotreated effluent; f) separation to obtain at least one gaseous effluent and a hydrotreated hydrocarbon liquid effluent.

Description

[Technical Field]

[0001] The present invention relates to a method for processing plastic pyrolysis oil and / or solid recovery fuel containing impurities to obtain a hydrocarbon spill that can be upgraded by being incorporated at least partially directly into naphtha or diesel pools or as feedstock for steam cracking units. More specifically, the present invention relates to a method for processing feedstock obtained from the pyrolysis of plastic waste and / or SRF to remove at least some of the impurities that may be present in large quantities in the feedstock, and to enable the feedstock to be hydrogenated and upgraded. [Background technology]

[0002] Plastics obtained from collection and sorting channels may undergo a pyrolysis process to obtain, in particular, pyrolysis oil. These plastic pyrolysis oils are commonly burned for power generation and / or used as fuel in industrial or urban heating boilers.

[0003] Solid recovered fuels (SRF), also known as "refuse-derived fuel" or RDF, are solid harmless wastes prepared for energy recovery from any of household and similar wastes, wastes from economic activities or wastes from construction and demolition. SRF generally consists of a mixture of residues from the recycling of various types of wastes, including any combustible waste, such as used tyres, food by-products (fats, animal feed, etc.), viscose and wood waste, light fragments (WEEE) from shredders (such as used vehicles, electrical and electronic equipment), household and commercial wastes, certain municipal wastes, plastic wastes, fibres, wood, etc. SRF generally contains plastic waste. Currently, SRF is mainly recovered as energy. They can be used directly as an alternative to fossil fuels in co-firing facilities (coal and lignite power plants, cement plants, lime kilns) or household waste incineration units, or can be used indirectly in pyrolysis units dedicated to energy recovery: thus, SRF pyrolysis oil is generally burned for power generation or used as fuel in industrial or urban heating boilers.

[0004] Another route for upgrading SRF and / or plastic pyrolysis oils is to use these pyrolysis oils as feedstock for steam cracking units to (re)generate olefins, which are constituent monomers of a given polymer. However, plastic waste or SRF is generally a mixture of several polymers, for example, a mixture of polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, and polystyrene. Furthermore, depending on the application, plastics may contain, in addition to polymers, other compounds, such as plasticizers, pigments, dyes, or polymerization catalyst residues, as well as a wide variety of other organic and inorganic impurities from the separation operations of sorting centers, and the selectivity of the operation may not be perfect. Thus, oils obtained from the pyrolysis of plastics or SRF contain many impurities, in particular diolefins, metals, silicon, or halogenated compounds, especially chlorine-based compounds, heteroatoms, such as sulfur, oxygen, and nitrogen, and insoluble substances, often in high concentrations and in concentrations unsuitable for steam cracking units or units located downstream of steam cracking units, in particular for polymerization and selective hydrogenation methods. These impurities can cause handling problems, particularly corrosion, coking, or catalyst deactivation, or incompatibility with the target polymer's application. The presence of diolefins very often causes instability problems in the pyrolysis oil, characterized by the formation of gummy substances. Gummy substances and insoluble materials that may be present in the pyrolysis oil can cause clogging problems during processing.

[0005] Furthermore, during the steam cracking process, the yields of light olefins required in petrochemistry, particularly ethylene and propylene, highly depend on the quality of the feedstock sent for steam cracking. BMCI (Bureau of Mines Correlation Index) is often used to characterize hydrocarbon fractions. This index, developed for hydrocarbon products derived from crude oil, is calculated from measurements of density and average boiling point: it is equal to 0 for linear paraffins and equal to 100 for benzene. Thus, if the product being analyzed has an aromatic condensed structure, its value will be proportionally higher, and naphthenes have an intermediate BMCI between paraffins and aromatic compounds. Overall, the yield of light olefins increases when the paraffin content is high and, therefore, when the BMCI decreases. Conversely, the yield of unwanted heavy compounds and / or coke increases when the BMCI increases.

[0006] Patent Document 1 proposes an overall method for recycling plastic waste. This method is very general and relatively complex, leading from the thermal decomposition process of plastic waste directly to the steam cracking process. The method of the patent application (Patent Document 1) includes, among other things, a step of hydrotreating the liquid phase obtained directly from thermal decomposition, preferably under extremely severe conditions, particularly with respect to temperature, for example at a temperature of 260 - 300 °C, a step of separating the hydrotreated effluent, and then a step of hydrodealkylation of the separated heavy effluent, preferably at a high temperature, for example 260 - 400 °C.

[0007] The unpublished patent application FR20 / 01758 describes a method for treating plastic pyrolysis oil, which includes the following: a) A step of selectively hydrogenating the feedstock in the presence of hydrogen and a selective hydrogenation catalyst to obtain a hydrogenated effluent; b) A step of performing fixed-bed hydrotreating of the hydrogenated effluent in the presence of hydrogen and a hydrotreating catalyst to obtain a hydrotreated effluent; c) A process of separating hydrogenated effluent at a temperature of 50-370°C in the presence of an aqueous flow to obtain gaseous effluent, aqueous liquid effluent, and liquid hydrocarbon effluent; d) Depending on the circumstances, fractionate all or part of the hydrocarbon effluent obtained from step c) to obtain a gas stream and at least two hydrocarbon streams, which may be a naphtha fraction and a heavier fraction; e) Recycling steps to selective hydrogenation steps a) and / or hydrogenation steps b), including a phase for recovering a portion of the hydrocarbon effluent obtained from separation step c) or a portion of the hydrocarbon flow obtained from fractionation step d) and / or at least one of the hydrocarbon flow obtained from fractionation step d).

[0008] According to patent application FR 20 / 01758, the naphtha fraction obtained from the fractionation step may be sent in whole or in part to either a steam cracking unit or a naphtha pool obtained from conventional petroleum feedstock, or it may be recycled to step e).

[0009] The heavier fractions obtained from the fractionation process may be sent, in whole or in part, to either a steam cracking unit or a pool of diesel or kerosene obtained from conventional petroleum feedstocks, or they may be recycled to process e).

[0010] Unpublished patent applications FR20 / 08108 and FR20 / 08106, based on the method of FR20 / 01758, describe a method for processing plastic pyrolysis oil, incorporating one or two steps of hydrocracking in a fixed bed after a hydrotreatment step. These methods make it possible to minimize the yield of the heavy fraction and maximize the yield of the naphtha fraction by converting the heavy fraction to the naphtha fraction, which is the generally preferred fraction for steam cracking units, at least partially by hydrocracking. The heavier fraction can be sent to a steam cracking unit, but few refiners prefer this option. This is because the heavier fraction has a high BMCI and contains more naphthenic, naphtheno-aromatic, and aromatic compounds relative to the naphtha fraction, and therefore leads to a higher C / H ratio. This high ratio causes coking in the steam cracker, so a dedicated steam cracking furnace is required for this fraction. Furthermore, the steam decomposition of such heavy fractions yields notable products, particularly small amounts of ethylene and propylene, but more abundantly, pyrolysis gasoline.

[0011] The presence of impurities in the pyrolysis oil can lead to catalyst deactivation in hydrogenation units operated in fixed-bed reactors, particularly when these oils contain high levels of impurities, resulting in reduced cycle times. In fact, a major limitation of fixed-bed reactors is the need to shut down the unit to replace the catalyst. Furthermore, pyrolysis oils, especially those containing high levels of impurities, can cause clogging problems, particularly in the preheating furnace, feedstock / fluid exchanger, or on the bed head of the catalytic reactor.

[0012] Therefore, it would be advantageous to propose a method for processing pyrolysis oil that has a long catalytic cycle by allowing catalyst replacement without shutting down the unit, while simultaneously producing an alkane-rich fraction that can be easily upgraded in the steam cracking unit.

[0013] Hydrogenation conversion units operating on boiling beds, jet beds, and even moving beds can process this type of feedstock with systems that add fresh catalyst and remove spent catalyst without stopping the unit. The addition of fresh catalyst and removal of spent catalyst are generally performed continuously, semi-continuously, or periodically. These systems compensate for catalyst deactivation due to impurities in the pyrolysis products and solve the problem of catalyst bed clogging in reactors operating on fixed beds, allowing the hydrogenation conversion unit to have long cycle times without the need to stop for catalyst replacement.

[0014] Furthermore, if such a hydrogenation conversion unit is located upstream of the hydrogenation treatment unit, the cycle time of the latter will be increased by the hydrogenation treatment reaction that is partially carried out in the hydrogenation conversion unit beforehand.

[0015] Similarly, the hydrocracking reaction carried out in the hydrogenation conversion unit makes it possible to convert at least a portion of the heavy compound into a lighter compound. This allows, firstly, to supply a fraction that is generally easier to process to the hydrogenation unit, and secondly, to obtain a fraction that has a lower BMCI and is therefore particularly suitable for the steam cracking unit. [Prior art documents] [Patent Documents]

[0016] [Patent Document 1] International Publication No. 2018 / 055555 [Overview of the Initiative] [Means for solving the problem]

[0017] (Summary of the invention) The present invention relates to a method for processing feedstock containing SRF and / or plastic pyrolysis oil, comprising the following: a) A selective hydrogenation step, depending on the circumstances; carried out in the presence of at least one selective hydrogenation catalyst in a reaction section that supplies the feed material and a hydrogen-containing gas stream, at a temperature of 100 to 280°C, a partial pressure of hydrogen of 1.0 to 20.0 absolute MPa, and a space velocity of 0.3 to 10.0 h⁻¹. -1 This yields hydrogenated effluent; b) Hydrogenation conversion step; carried out in a hydrogenation conversion reaction section, using at least one boiling bed reactor, a jet bed reactor, or a moving bed reactor, the reactor containing at least one hydrogenation conversion catalyst, and at least the feed material or the hydrogenated effluent obtained at the end of step a) and a hydrogen-containing gas stream being supplied to the hydrogenation conversion reaction section, the operating temperature of the hydrogenation conversion reaction section being 250 to 450°C, the partial pressure of hydrogen being 1.0 to 20.0 absolute MPa, and the space velocity per hour being 0.05 to 10.0 h -1 This yields hydrogenated effluent; c) Separation step; the hydrogenated effluent obtained from step b) and an aqueous solution are fed together, and the temperature during this step is 50 to 450°C, and at least one type of gaseous effluent, aqueous effluent, and hydrocarbon effluent are obtained; d) A step of fractionating all or part of the hydrocarbon effluent obtained from step c) to obtain at least one gas stream, a hydrocarbon fraction containing compounds with a boiling point of 385°C or less, and a hydrocarbon fraction containing compounds with a boiling point greater than 385°C; e) Hydrogenation process; carried out in a hydrogenation reaction section, using at least one fixed-bed reactor, the fixed-bed reactor containing n catalyst beds, where n is an integer of 1 or more, each containing at least one hydrogenation catalyst, and at least a portion of the hydrocarbon fraction obtained from step d) containing a compound with a boiling point of 385°C or less, and a gas stream containing hydrogen are fed to the hydrogenation reaction section, the temperature when operating the hydrogenation reaction section is 250 to 430°C, the partial pressure of hydrogen is 1.0 to 20.0 absolute MPa, and the space velocity per hour is 0.1 to 10.0 h -1This yields hydrogenated effluent; f) Separation step; the hydrogenated effluent and aqueous solution obtained from step e) are fed to obtain at least gaseous effluent and hydrogenated liquid hydrocarbon effluent.

[0018] In the following text, unless otherwise indicated, the term “pyrolysis oil” means oil obtained from the pyrolysis of plastics and / or SRF.

[0019] One advantage of the method according to the present invention is that the pyrolysis oil is purified from at least some of its impurities, thereby it can be upgraded by hydrogenation, and therefore it can be adapted for processing in a steam cracking unit, in particular by directly incorporating it into a fuel pool and / or by obtaining light olefins that can function as monomers in the production of polymers.

[0020] Another advantage of the present invention is that it prevents the risk of clogging and / or corrosion of the processing unit in which the method of the present invention is carried out, a risk exacerbated by the presence (often in large quantities) of diolefins, metals, and halogenated compounds in the pyrolysis oil.

[0021] The method of the present invention makes it possible to obtain hydrocarbon effluent from pyrolysis oil in which impurities from the starting pyrolysis oil have been at least partially removed, thus limiting operability issues, such as corrosion, coking, or catalyst deactivation, in which case these impurities may occur particularly in the steam cracking unit and / or units located downstream of the steam cracking unit, especially in the polymerization and selective hydrogenation units. The removal of at least some of the impurities from the pyrolysis oil also makes it possible to increase the range of applications for the target polymer and will reduce application incompatibility.

[0022] The present invention relates to the recycling of plastics and / or SRF, and proposes a method for processing, purifying, and hydrogenating the oil resulting from pyrolysis. By performing the hydrogenation process using a system for adding fresh catalyst and removing used catalyst without stopping upstream units of the fixed-bed hydrogenation process, it becomes particularly possible to process pyrolysis oil containing many impurities.

[0023] By performing the hydrogenation conversion process using a system that adds fresh catalyst and removes used catalyst without stopping the upstream units of the fixed-bed hydrogenation process, it becomes possible to obtain a longer cycle time for hydrogenation conversion, as well as a longer cycle time for the hydrogenation process. In addition, the risk of clogging of the catalyst bed (one or more) in the hydrogenation process is reduced.

[0024] By performing the hydrogenation conversion process using a system for adding fresh catalyst and removing used catalyst without stopping upstream units in the fixed-bed hydrogenation process, it becomes possible to convert at least a portion of the heavy compounds into lighter compounds, thereby obtaining an improved yield of a fraction suitable for steam cracking units, which, when sent for steam cracking, can yield an improved yield of light olefins, while simultaneously particularly reducing the risk of large-scale coke formation and / or corrosion encountered during subsequent processes, such as the steam cracking of pyrolysis oil.

[0025] The portion of oil that was not converted by hydrogenation corresponds to a hydrocarbon fraction containing compounds with a boiling point above 385°C obtained from fractionation step d), and a portion of this is preferably upgraded by recycling it back into the hydrogenation step. Furthermore, the C2-C4 compounds produced during hydrogenation may be sent to steam cracking, which makes it possible to improve the yield of light olefins (ethylene and propylene).

[0026] According to one modification, the method includes the selective hydrogenation step a).

[0027] According to one variation, the hydrocarbon fraction obtained from step d) containing compounds with a boiling point above 385°C is recycled, at least partially, to step b).

[0028] According to one variation, the method includes a step a0) of pre-treating the feedstock, which is performed upstream of any selective hydrogenation step a) or upstream of the hydrogenation conversion step, and includes a filtration step and / or a washing step with water and / or an adsorption step.

[0029] According to one variation, the hydrogenated liquid hydrocarbon effluent obtained from step f) is sent, either whole or partially, to a steam decomposition step h). Step h) is carried out in at least one pyrolysis furnace at a temperature of 700–900°C and a pressure of 0.05–0.3 relative MPa.

[0030] According to one variation, the method also includes a recycling step g), in which a portion of the hydrogenated liquid hydrocarbon effluent obtained from the separation step f) is sent to an optional selective hydrogenation step a) and / or a hydrogenation conversion step b) and / or a hydrogenation step e) and / or a hydrocracking step e').

[0031] According to one variation, separation step f) includes fractionation, which, in addition to the gas flow, makes it possible to obtain a naphtha fraction containing compounds with a boiling point of 175°C or less, and a diesel fraction containing compounds with a boiling point greater than 175°C but less than 385°C.

[0032] According to one variation, the method also includes a hydrocracking step e'), which is carried out in a hydrocracking reaction section and uses at least one fixed bed. The fixed bed comprises n catalyst beds, where n is an integer of 1 or more, each containing at least one hydrocracking catalyst. The hydrocracking reaction section is fed at least a diesel fraction containing the hydrotreated effluent obtained from step e) and / or a compound with a boiling point greater than 175°C and less than 385°C obtained from step f), and a gas stream containing hydrogen, the operating temperature of the hydrocracking reaction section being 250 to 450°C, the partial pressure of hydrogen being 1.5 to 20.0 absolute MPa, and the space velocity per hour being 0.1 to 10.0 h -1 The hydrocracking effluent is obtained and sent to separation step f).

[0033] According to one variation, separation step f) also includes fractionation of the naphtha fraction containing compounds with a boiling point of 175°C or less into a light naphtha fraction containing compounds with a boiling point of 80°C and a heavy naphtha fraction containing compounds with a boiling point of 80 to 175°C.

[0034] According to this modification, at least a portion of the heavy naphtha fraction is sent to an aromatics complex including at least one reforming step, and / or at least a portion of the light naphtha fraction is sent to a steam cracking step h).

[0035] According to one variation, the selective hydrogenation catalyst of step a) comprises a support selected from alumina, silica, silica-alumina, magnesia, clay and mixtures thereof, and a hydrogenation-dehydrogenation functional group comprising at least one group VIII element and at least one group VIB element, or at least one group VIII element.

[0036] According to one variation, when step b) is carried out in a boiling bed or a moving bed, the hydrogenation-conversion catalyst in step b) includes a supported catalyst comprising a group VIII metal selected from the group formed by Ni, Pd, Pt, Co, Rh and / or Ru, and optionally a group VIB metal selected from the group formed by Mo and / or W, on an amorphous mineral support selected from the group formed by alumina, silica, silica-alumina, magnesia, clay and mixtures of at least two of these minerals; when step b) is carried out in a jet bed, the hydrogenation-conversion catalyst in step b) includes a dispersed catalyst containing at least one element selected from the group formed by Mo, Fe, Ni, W, Co, V and Ru.

[0037] According to one variation, the hydrogenation catalyst of step e) comprises a support selected from the group consisting of alumina, silica, silica-alumina, magnesia, clay and mixtures thereof, and a hydrogenation dehydrogenation functional group comprising at least one group VIII element and / or at least one group VIB element.

[0038] According to one variation, the hydrocracking catalyst of step e') comprises a support selected from alumina halides, a combination of boron and aluminum oxides, amorphous silica-alumina and zeolites, and a hydrodehydrogenating functional group comprising at least one group VIB metal selected individually or as a mixture from chromium, molybdenum and tungsten, and / or at least one group VIII metal selected from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum.

[0039] According to one variation, the raw material has the following characteristics: - The aromatic compound content is 0-90% by weight. - The halogenated compound content is 2 to 5000 ppm by weight. - The metallic element content is 10 to 10,000 ppm by weight. - Contains iron element at a concentration of 0-100 ppm by weight. - The silicon content ranges from 0 to 1000 ppm by weight.

[0040] The present invention also relates to products that can be obtained through the processing method according to the present invention.

[0041] According to one variation, the product comprises the following relative to the total weight of the product: - The total content of metallic elements is 5.0 ppm by weight or less. - Contains iron element at a content of 100 ppb by weight or less, - The silicon content is 1.0 ppm by weight or less. - The sulfur content is 500 ppm by weight or less. - The nitrogen content is 100 ppm by weight or less. - The chlorine content is 10 ppm by weight or less.

[0042] According to the present invention, pressure is absolute pressure, also denoted as "abs.", and is given in absolute MPa (or MPa abs.) unless otherwise specified.

[0043] According to the present invention, the expressions "included between ... and ..." and "between ... and ..." are equivalent, meaning that both limit values ​​of the interval are included within the range of values ​​stated. If this were not the case, and if both limit values ​​were not included within the range stated, such clarification would be provided by the present invention.

[0044] For the purposes of the present invention, various ranges of parameters for a given process, such as pressure ranges and temperature ranges, may be used individually or in combination. For example, for the purposes of the present invention, a preferred range of pressure values ​​may be combined with a more preferred range of temperature values.

[0045] Specific and / or preferred embodiments of the present invention may be described below. These may be carried out separately or in combination, and there are no limitations on the combination, as long as it is technically feasible.

[0046] In the following text, 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 according to the CAS classification corresponds to the metals in columns 8, 9, and 10 of the new IUPAC classification.

[0047] The metal content is measured by X-ray fluorescence. [Modes for carrying out the invention]

[0048] (Detailed explanation) (Feed material) According to the present invention, “plastic pyrolysis oil or SRF pyrolysis oil” is an oil obtained from the pyrolysis of plastics, preferably plastic waste, in particular from collection and sorting channels or from the pyrolysis of SRF, and is advantageously in liquid form at room temperature. It contains, in particular, a mixture of hydrocarbon compounds, in particular paraffinic, olefinic, naphthenic, and aromatic compounds. At least 80% by weight of these hydrocarbon compounds preferably have a boiling point of less than 700°C, preferably less than 550°C. In particular, depending on the origin of the pyrolysis oil, the oil may contain up to 70% by weight of paraffinic compounds, up to 90% by weight of olefinic compounds, and up to 90% by weight of aromatic compounds, and it is understood that the sum of the paraffinic compounds, olefinic compounds, and aromatic compounds is 100% by weight of the hydrocarbon compounds.

[0049] The density of pyrolysis oil was measured at 15°C according to the ASTM D4052 method and is generally 0.75–0.99 g / cm³. 3 Preferably 0.75 to 0.95 g / cm³ 3 That is the case.

[0050] Pyrolysis oil may contain, and usually does contain, impurities such as metals, particularly iron, silicon, or halogenated compounds, particularly chlorinated compounds. These impurities may be present in high concentrations in plastic pyrolysis oil, for example, up to 500 ppm by weight, even up to 1,000 ppm by weight, and even up to 5,000 ppm by weight, for halogen elements provided by halogenated compounds, and up to 2,500 ppm by weight, and even up to 10,000 ppm by weight, for metallic or semimetallic elements. Alkali metals, alkaline earth metals, transition metals, post-transition metals, and metalloids may be likened to metallic contaminants called metals or metallic or semimetallic elements. Pyrolysis oil may contain up to 200 ppm by weight, and even up to 1,000 ppm by weight, of silicon, and up to 15 ppm by weight, and even up to 100 ppm by weight, of iron. The pyrolysis oil may also contain other impurities, such as heteroatoms, particularly provided by sulfur compounds, oxygen compounds, and / or nitrogen compounds, in a concentration generally less than 20,000 ppm by weight, preferably less than 10,000 ppm by weight.

[0051] The method according to the present invention is particularly suitable for treating pyrolysis oil containing impurities. This means that the supply material has the following characteristics: - The aromatic content is 0-90% by weight, often 20-90% by weight, and may be 50-90% by weight; - The halogen content is 2 to 5000 ppm by weight, often 200 to 5000 ppm by weight, and may also be 500 to 5000 ppm by weight; - The content of metallic elements is 10 to 10,000 ppm by weight, often 2,000 to 10,000 ppm by weight, and may be 2,250 to 5,000 ppm by weight; - Contains iron element in a concentration of 0-100 ppm by weight, often 10-100 ppm by weight, and may be 15-100 ppm by weight; - The silicon content is 0 to 1000 ppm by weight, often 100 to 1000 ppm by weight, and may be 200 to 1000 ppm by weight.

[0052] The method according to the present invention is particularly suitable for processing pyrolysis oil containing many impurities. This means that the raw material has the following characteristics: - The aromatic compound content is 50% to 90% by weight; - The halogenated compound content is 500-5000 ppm by weight; - The metallic element content is 2250-10000 ppm by weight; - Contains iron element at a concentration of 15-100 ppm by weight; - The silicon content is 200-1000 ppm by weight.

[0053] The feedstock for the method according to the present invention comprises at least one type of SRF and / or plastic pyrolysis oil. The feedstock may consist only of plastic pyrolysis oil (one or more types), only of SRF pyrolysis oil (one or more types), or only a mixture of SRF and plastic pyrolysis oil (one or more types). Preferably, the feedstock contains at least 50% by weight, preferably 50% to 100% by weight, and particularly preferably 75% to 100% by weight of SRF and / or plastic pyrolysis oil.

[0054] The feedstock of the method according to the present invention may include conventional petroleum-based feedstocks and / or feedstocks obtained from the conversion of lignocellulose resources, which are then co-treated with SRF and / or plastic pyrolysis oils.

[0055] SRF and / or plastic pyrolysis oils may be obtained from thermal catalytic pyrolysis treatment, or they may be prepared by hydrothermal decomposition (thermal decomposition in the presence of a catalyst and hydrogen).

[0056] (Pre-processing (optional)) The feedstock containing pyrolysis oil may advantageously be pretreated in an optional pretreatment step a0) before any optional hydrogenation step a) or the hydrogenation conversion step b) if step a) is absent, to obtain a pretreated feedstock, which is fed to step a) or step b).

[0057] This optional pretreatment step a0) makes it possible to reduce the amount of contaminants that may be present in the feedstock containing pyrolysis oil, particularly the amounts of silicon and metals. Therefore, an optional step a0) of pretreatment of the feedstock containing pyrolysis oil may be carried out especially when the feedstock contains metallic elements in excess of 50 ppm by weight, particularly in excess of 100 ppm by weight, more specifically in excess of 200 ppm by weight.

[0058] The optional pretreatment step a0) may be carried out via any method known to those skilled in the art to reduce the amount of contaminants. It may include, inter alia, a filtration step and / or a washing step with water and / or an adsorption step.

[0059] According to one variant, the optional pretreatment step a0) is carried out in an adsorption section, in the presence of at least one adsorbent. The temperature at which the optional pretreatment step a0) is carried out is from 0 to 150 °C, preferably from 5 to 100 °C, and the pressure at that time is from 0.15 to 10.0 absolute MPa, preferably from 0.2 to 1.0 absolute MPa. The adsorption section is advantageously operated in the presence of at least one adsorbent, which is preferably of the alumina type and has a specific surface area of 100 m 2 / g or more, preferably 200 m 2 / g or more. The specific surface area of the adsorbent is advantageously 600 m 2 / g or less, particularly 400 m 2It is less than / g. 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 the standard ASTM D 3663, which was established from the Brunauer-Emmett-Teller method described in the periodical The Journal of the American Chemical Society, 60, 309 (1938).

[0060] Advantageously, the adsorbent contains less than 1% by weight of metallic elements, and preferably does not contain metallic elements. The term "metallic elements of the adsorbent" should be understood to refer to elements from groups 6-10 of the periodic table (new IUPAC classification).

[0061] The adsorption section of any step a0) includes at least one adsorption column, preferably at least two adsorption columns, and more preferably two to four adsorption columns, the adsorption columns containing the adsorbent. If the adsorption section includes two adsorption columns, one mode of operation may be called a “swing” operation in technical terms, in which one column is online, i.e., in service, while the other column is in reserve. If the adsorbent in the online column is depleted, this column is separated, while the column in reserve is brought online, i.e., in service. The used adsorbent may then be regenerated in situ and / or replaced with fresh adsorbent, and the column containing it may be brought online again where the other column has been separated.

[0062] Another operating configuration involves operating at least two columns in series. When the adsorbent in the column located at the head becomes depleted, this first column is separated, and the used adsorbent is either regenerated on-site or replaced with fresh adsorbent. The columns are then brought back online at their final position, etc. This operation is known as a variable-arrange configuration, or by the term PRS (Permutable Reactor System), or also by the specialized term "lead and lag." The combination of at least two adsorption columns makes it possible to overcome the potential for rapid poisoning and / or clogging of the adsorbent due to the combined action of metallic contaminants, diolefins, gums derived from diolefins, and insoluble substances that may be present in the pyrolysis oil of the plastic being treated. The reason for this is that the presence of at least two adsorption columns facilitates the replacement and / or regeneration of the adsorbent, advantageously without stopping the pretreatment unit, or even the method itself, thus reducing the risk of clogging, thus avoiding unit shutdowns due to clogging, controlling costs, and limiting adsorbent consumption.

[0063] The optional pretreatment step a0) may optionally feed at least a portion of the recycled flow (preferably the recycled flow obtained from step g) of this method) either as a mixture with the feedstock containing pyrolysis oil or separately.

[0064] Through the aforementioned optional pretreatment step a0), it becomes possible to obtain pretreated feedstock, which is then supplied to a selective hydrogenation step a) if one exists, or to a hydrogenation conversion step b).

[0065] (Selective hydrogenation step a) (Optional) According to the present invention, the method may include a step a) of selective hydrogenation of a feedstock containing pyrolysis oil, which is carried out in an amount of soluble hydrogen just necessary for the selective hydrogenation of diolefins present in the pyrolysis oil, under hydrogen pressure and temperature conditions that allow the feedstock to remain in the liquid phase in the presence of hydrogen. Selective hydrogenation of diolefins in the liquid phase thus makes it possible to avoid or at least limit the formation of a “gummy substance” that could clog the reaction section of the hydrogenation step e), i.e., polymerization of the diolefin, for which oligomers and polymers are formed. The selective hydrogenation step a) makes it possible to selectively obtain a hydrogenated effluent, i.e., an effluent with a reduced olefin, particularly diolefin, content.

[0066] According to the present invention, the selective hydrogenation step a) is carried out in a reaction section to which at least a gas stream containing hydrogen (H2) is fed, along with the feedstock containing pyrolysis oil, or a pre-treated feedstock obtained from an optional pre-treatment step a0). Optionally, the reaction section of step a) may be fed, at least a portion of a recycled stream (preferably a recycled stream obtained from an optional step g)) either as a mixture with the feedstock (preferably pre-treated) or separately from the feedstock (preferably pre-treated), preferably directly, to at least one inlet of the reactor in the reaction section of step a). The introduction of at least a portion of the recycled stream into the reaction section of the selective hydrogenation step a) is advantageous in that it is possible to dilute impurities in the feedstock (preferably pre-treated) and to control the temperature, in particular, the temperature in the reaction section.

[0067] The reaction section comprises selective hydrogenation, preferably in a fixed bed, in the presence of at least one selective hydrogenation catalyst, at a temperature advantageously 100-280°C, preferably 120-260°C, preferably 130-250°C, with a partial pressure of hydrogen of 1.0-20.0 absolute MPa, preferably 5.0-15.0 absolute MPa, and a space velocity per hour (HSV) of 0.3-10.0 h. -1 Preferably 0.5 to 5.0 hours -1 The hourly space velocity (HSV) is defined here as the ratio of the hourly volume flow rate of the feedstock (which may be pre-treated in some cases) containing pyrolysis oil to the volume of the catalyst (one or more types). The amount of hydrogen (H2)-containing gas flow supplied to the reaction section in step a) is advantageously determined by the hydrogen coverage ratio of the volume of the feedstock (m³). 3 ) Hydrogen 1-200 Nm 3 (Nm 3 / m 3 ), preferably the volume of the supplied raw material (m³ 3 ) Hydrogen per unit: 1-50 Nm 3 (Nm 3 / m 3 ), preferably the volume of the supplied raw material (m³ 3 ) Hydrogen per unit: 5-20 Nm 3 (Nm 3 / m 3 The hydrogen coverage is defined as the ratio at 15°C of the volumetric flow rate of hydrogen taken in under standard temperature and pressure conditions versus the volumetric flow rate of the “fresh” feedstock, i.e., the feedstock to be treated (which may be pre-treated in some cases), without taking into account any recycled portions (volume of feedstock (m³). 3 ) Standard H2 m per unit 3 (Nm 3 The hydrogen-containing gas stream supplied to the reaction section of step a) may consist of a hydrogen feed and / or recycled hydrogen specifically obtained from the separation step c).

[0068] The selective hydrogenation step a) is preferably carried out in a fixed bed. It may also be carried out in a boiling bed or a moving bed.

[0069] Advantageously, the reaction section of step a) comprises 1 to 5 reactors. According to certain embodiments of the present invention, the reaction section comprises 2 to 5 reactors, which are operated in a permutable reactor system, referred to by the term PRS or by the term "read-and-drag". The combination of at least two reactors in the PRS configuration makes it possible to separate one reactor, discharge the spent catalyst, refill the reactor with fresh catalyst, and return the reactor to an operational state without stopping the method. The PRS technique is described in particular in patent FR2681871.

[0070] Advantageously, reactor inserts, such as filter plate types, may be used to prevent clogging of the reactor(s). An example of a filter plate is described in patent FR3051375.

[0071] Advantageously, the selective hydrogenation catalyst comprises a support, preferably a mineral support, and a hydrogenation dehydrogenation functional group.

[0072] According to one variation, the hydrogenation-dehydrogenation functional group comprises, in particular, at least one group VIII element and at least one group VIB element, wherein the group VIII element is preferably selected from nickel and cobalt, and the group VIB element is preferably selected from molybdenum and tungsten. According to this variation, the total content of metallic element oxides from group VIB and group VIII is preferably 1% to 40% by weight, and preferably 5% to 30% by weight, relative to the total weight of the catalyst. The weight ratio of metal oxides of group VIB metals (one or more) relative to group VIII metals (one or more) is preferably 1 to 20, preferably 2 to 10.

[0073] According to this modification, the reaction section of step a) includes a selective hydrogenation catalyst comprising, for example, 0.5% to 12% by weight of nickel, preferably 1% 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), on a support, preferably on a mineral support, preferably on an alumina support.

[0074] According to another modification, the hydrogenation-dehydrogenation functional group comprises, and preferably consists of, at least one group VIII element, preferably nickel. According to this modification, the nickel oxide content is preferably 1% to 50% by weight, and preferably 10% to 30% by weight, relative to the weight of the catalyst. This type of catalyst is preferably used in its reduced form on a support, preferably a mineral support, and preferably an alumina support.

[0075] The support for the at least one selective hydrogenation 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 oxides, especially boron trioxide, zirconia, ceria, titanium oxide, phosphorus pentoxide, and mixtures thereof. Preferably, the at least one selective hydrogenation catalyst comprises an alumina support and is 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 alumina, and preferably at least 0.001% by weight relative to the total weight of alumina. If boron trioxide (B2O5) is present, its concentration is less than 10% by weight relative to the weight of alumina, and preferably at least 0.001% by weight relative to the total weight of alumina. The alumina used may be, for example, gamma (γ) or eta (η) alumina.

[0076] The selective hydrogenation catalyst is, for example, in the form of an extruded product.

[0077] Much more preferably, in order to hydrogenate the diolefin as selectively as possible, step a) may use, in addition to the selective hydrogenation catalyst described above, at least one selective hydrogenation catalyst used in step a), which 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, slightly packed with metal, is preferably placed upstream of the selective hydrogenation catalyst described above.

[0078] In some cases, the feedstock containing pyrolysis oil (which may be pre-treated and / or, in some cases, obtained from a recycled flow (preferably any process g)) may be pre-mixed with a gas flow containing hydrogen before being introduced into the reaction section.

[0079] The supply material (which may be pre-treated and / or, in some cases, pre-mixed with at least a portion of the recycled flow (preferably obtained from any process g) and / or, in some cases, as a mixture with the gas flow) may be heated, for example, by heat exchange, in particular by heat exchange with the hydrogenated effluent from process b) before being introduced into the reaction section of process a) to a temperature close to the temperature applied in the reaction section to which it is supplied.

[0080] The content of impurities, particularly diolefins, in the hydrogenated effluent obtained at the end of step a) is reduced relative to the content of the same impurities, particularly diolefins, in the feedstock for this method. Selective hydrogenation step a) generally makes it possible to convert at least 90%, preferably at least 99%, of the diolefins contained in the initial feedstock. Step a) also makes it possible to remove other contaminants, such as silicon, at least partially. The hydrogenated effluent obtained at the end of selective hydrogenation step a) is preferably sent directly to hydrogenation conversion step b).

[0081] (Hydrogenation conversion process b)) According to the present invention, the processing method includes a hydrogenation conversion step b). Step b) is carried out in a hydrogenation conversion reaction section and includes at least one boiling bed reactor, a jet bed reactor and / or a moving bed reactor, the reactors each containing at least one hydrogenation conversion catalyst, the hydrogenation conversion reaction section is fed at least a hydrogenated gas stream and the hydrogenated effluent obtained from the feed material or step a), which may optionally be mixed with at least a portion of a recycled stream (preferably obtained from any step g)), to obtain a hydrogenated effluent.

[0082] Advantageously, step b) includes hydrogenation conversion reactions well known to those skilled in the art, more specifically, hydrogenation treatment reactions such as hydrogenation, hydrogenation, demetallation, hydrogenation, desulfurization, and denitrification of olefin compounds, aromatic compounds, and halogenated compounds, and hydrogenolysis (HCK), thermal decomposition, and polycondensation reactions (formation of coke) that lead to ring opening of the naphthenic ring or splitting of the paraffin into several fragments of lower molecular weight, although polycondensation reactions are undesirable.

[0083] The hydrogenation-conversion reaction section of step b) may be fed at least a portion of the recycled flow (preferably obtained from any step g). The portion(s) or the entirety of the recycled flow may be introduced into the hydrogenation-conversion reaction section either as a mixture with the feedstock or the hydrogenated effluent obtained from step a) or separately. The introduction of at least a portion of the recycled flow is advantageous in diluting impurities still present in the hydrogenated effluent and controlling the temperature, in particular limiting the temperature rise, in the catalyst bed(s) of the hydrogenation-conversion reaction section, which involves highly exothermic reactions.

[0084] In some cases, step b) may include a heating section located upstream of the hydrogenation-conversion reaction section, in which the feed material or the hydrogenated effluent obtained from step a) is heated to a temperature suitable for hydrogenation-conversion, i.e., 250-450°C. The optional heating section may therefore include one or more exchangers (preferably enabling heat exchange between the feed material or hydrogenated effluent and the hydrogenated-converted effluent) and / or a preheating furnace.

[0085] Advantageously, the hydrogenation-conversion reaction section is operated at a pressure equivalent to that used in the selective hydrogenation step a), if such a reaction section exists, but at a higher temperature than that of the selective hydrogenation step a). Therefore, regardless of whether a boiling bed, jet bed, and / or moving bed reaction section is used, the hydrogenation-conversion temperature when the hydrogenation-conversion reaction section is operated is advantageously 250-450°C, preferably 350-420°C, with a partial pressure of hydrogen of 1.0-20.0 absolute MPa, more preferably 5.0-15.0 absolute MPa, and a space velocity per hour (HSV) of 0.05-10.0 h -1 Preferably 0.1 to 5.0 hours -1According to the present invention, the "hydrogenation conversion temperature" corresponds to the average temperature in the hydrogenation conversion reaction section of step b). The hydrogenation conversion temperature is advantageously determined by those skilled in the art, depending on the catalyst system, equipment and their configuration. For example, the boiling bed hydrogenation conversion temperature is determined by taking the arithmetic mean of the temperature measurements in the catalyst bed. The space velocity per hour (HSV) is defined here as the ratio of the volumetric flow rate per hour of the hydrogenated effluent obtained from step a) to the volume of the catalyst (one or more). The hydrogen coverage in step b) is advantageously determined by the volume (m³) of the fresh feed material supplied to step a). 3 ) Hydrogen content: 50-1000 Nm 3 Preferably, the volume (m³) of fresh raw material to be supplied to step a) 3 ) Hydrogen per unit: 60-500 Nm 3 Preferably, the volume (m³) of fresh raw material to be supplied to step a) 3 ) Hydrogen per unit: 100-300 Nm 3 The hydrogen coverage is defined here as the ratio of the volumetric flow rate of hydrogen taken under standard temperature and pressure conditions to the volumetric flow rate of the fresh feed material supplied to process a), i.e., the feed material containing pyrolysis oil, or the feed material supplied to process a) (which may be pre-treated in some cases) (volume of fresh feed material (m³). 3 ) Standard H2 m per unit 3 (Nm 3 (as described). The hydrogen may consist of supply hydrogen and / or recycled hydrogen specifically obtained from separation.

[0086] A key feature of the method according to the present invention is that the hydrogenation conversion step is carried out in a reaction section that allows for the addition of fresh catalyst and the removal of spent catalyst without stopping the unit. Such a system is a hydrogenation conversion unit operated in a boiling bed, a jet bed, and / or even a moving bed. The addition of fresh catalyst and the removal of spent catalyst can therefore be carried out continuously, semi-continuously, or periodically.

[0087] (Boiling bed hydrogenation conversion process b)) Thus, according to the first modification, the hydrogenation-conversion step b) is carried out in a hydrogenation-conversion reaction section, which includes at least one boiling bed reactor.

[0088] The functionalization of boiling bed reactors is generally known, including the recycling of reactor liquid upward through a stirred bed of catalyst. A mixture of feedstock and hydrogen is passed from the bottom upward over a bed of catalyst particles at a flow rate such that the liquid and gas pass through the bed from the bottom upward, while the particles are subjected to forced random movement. The movement of the catalyst bed is controlled by the flow of the recycled liquid, and in a steady state, the aggregate of catalyst does not rise above a definable level in the reactor. The vapors and liquids to be hydrogenated pass through the upper level of the bed of catalyst particles to a zone substantially free of catalyst, which they are then discharged from the top of the reactor. A portion of the reactor liquid is continuously recycled back into the reactor. Boiling bed technology uses supported catalysts, generally in the form of extruded or beaded material, with a diameter of approximately 1 mm or less. The catalyst remains in the reactor and is not discharged with the product. Catalytic activity can be maintained constant by online replacement of the catalyst. Therefore, there is no need to stop the unit to replace spent catalyst or to raise the reaction temperature along the cycle to compensate for deactivation. Furthermore, by operating under constant operating conditions, it is possible to obtain consistent product yield and quality along the cycle. In addition, because the catalyst is kept agitated due to the extensive recycling of the liquid, the reactor pressure drop is kept low and constant, and the heat generated by the reaction is rapidly averaged out across the catalyst bed.

[0089] The spent catalyst is partially replaced with fresh catalyst by withdrawal from the bottom of the reactor, and fresh or new catalyst is introduced at regular time intervals, i.e., explosively or nearly continuously, either at the top or bottom of the reactor. Fresh catalyst may be introduced, for example, daily. The exchange rate of spent catalyst with fresh catalyst may range, for example, from about 0.01 kilograms to about 10 kilograms per cubic meter of feedstock. This withdrawal and exchange are carried out using a device that enables the continuous functioning of this hydrogenation conversion process. The unit typically includes an internal recirculation pump for maintaining the catalyst in the boiling bed by the continuous recycling of at least a portion of the liquid withdrawn at the top of the reactor and reinjected at the bottom of the reactor. It is also possible to send the spent catalyst withdrawn from the reactor to a regeneration zone (where its contained carbon and sulfur are removed), and then return this regenerated catalyst to the hydrogenation conversion process. It is also possible to send the regenerated catalyst to an activation recovery zone (where processes aimed at improving catalyst activity, such as pre-sulfidation and additives, are carried out), and then return this activated catalyst to the hydrogenation conversion process.

[0090] Catalysts used in boiling beds are widely available. These are granular catalysts, and their size never reaches that of catalysts used in jet beds. Catalysts are usually in the form of extruded or beaded materials. Typically, they contain at least one hydrogenation-dehydrogenating element deposited on an amorphous support. Generally, supported catalysts contain a group VIII metal selected from the group formed by Ni, Pd, Pt, Co, Rh and / or Ru, and any group VIB metal selected from the group formed by Mo and / or W, on an amorphous mineral support selected from the group formed by alumina, silica, silica-alumina, magnesia, clay and mixtures of at least two of these minerals. CoMo / alumina and NiMo / alumina catalysts are the most common.

[0091] The total content of metallic element oxides from Group VIB and Group VIII is preferably 0.1% to 40% by weight, preferably 5% to 35% by weight, relative to the total weight of the catalyst. The weight ratio of Group VIB metals (one or more) expressed as metal oxides relative to Group VIII metals (one or more) is preferably 1.0 to 20, preferably 2.0 to 10. For example, the hydrogenation-conversion reaction section of step b) of this method includes a hydrogenation-conversion catalyst containing 0.5% to 10% by weight of nickel, preferably 1% to 8% by weight, expressed as nickel oxide NiO, and 1.0% to 30% by weight of molybdenum, preferably 3.0% to 29% by weight, expressed as molybdenum oxide MoO3, relative to the total weight of the hydrogenation-conversion catalyst, on a mineral support, preferably an alumina support.

[0092] The support for the hydrogenation-conversion catalyst is preferably selected from alumina, silica, silica-alumina, magnesia, clay, and mixtures thereof. The support may also contain dopant compounds, in particular oxides selected from boron oxides, especially boron trioxide, zirconia, ceria, titanium oxide, phosphorus pentoxide, and mixtures thereof. Preferably, the hydrogenation-conversion catalyst comprises an alumina support, preferably an alumina support 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 alumina, and preferably at least 0.001% by weight relative to the total weight of alumina. If boron trioxide (B2O5) is present, its concentration is less than 10% by weight relative to the weight of alumina, and preferably at least 0.001% by weight relative to the total weight of alumina. The alumina used may be, for example, γ (gamma) or η (eta) alumina.

[0093] The hydrogenation-conversion catalyst is, for example, in the form of an extruded product or beads.

[0094] Advantageously, the specific surface area of ​​the hydrogenation catalyst used in step b) of this method is 250 m². 2 / g or more, preferably 300m 2 It is 1 / g or more. The specific surface area of ​​the hydrogenation catalyst is, advantageously, 800 m². 2 Less than or equal to / g, preferably 600m 2 / g or less, especially 400m 2 The specific surface area of ​​the hydrogenation catalyst is measured by the BET method. That is, the specific surface area is determined by nitrogen adsorption according to standard ASTM D 3663, which was established from the Brunauer-Emmett-Teller method described in the periodical The Journal of the American Chemical Society, 60, 309 (1938). Such a specific surface area makes it possible to further improve the removal of contaminants, especially metals, such as silicon.

[0095] Hydrogenation catalysts are distinguished from hydrogenation catalysts by their porosity, particularly by the presence of macroporosity, which is suitable for treating impurities, especially metallic impurities.

[0096] According to another aspect of the present invention, the hydrogenation-conversion catalyst also includes one or more organic compounds containing oxygen and / or nitrogen and / or sulfur. Such catalysts are often referred to as “additivated catalysts.” Generally, the organic compounds are selected from compounds containing one or more chemical functional groups selected from functional groups of carboxylic acids, alcohols, thiols, thioethers, sulfones, sulfoxides, ethers, aldehydes, ketones, esters, carbonates, amines, nitriles, imides, oximes, ureas, and amides, or compounds containing furan rings, or sugars.

[0097] (Jet bed hydrogenation conversion process b)) According to the second variation, the hydrogenation conversion step b) is carried out in a hydrogenation conversion reaction section including at least one jet-bed reactor, also called a slurry reactor. The feedstock, hydrogen, and catalyst are injected from below and flow as an upward flow. The hydrogenation-converted effluent and unused hydrogen and catalyst are withdrawn from the top. Slurry hydrogenation conversion technology uses a catalyst dispersed in the form of very small particles, the size of which is tens of microns or less (generally 0.001 to 100 μm). The catalyst, or its precursor, is injected at the reactor inlet along with the feedstock to be converted. The catalyst passes through the reactor along with the feedstock and the converted products, and they are then encompassed with the reaction products and exit the reactor. They are found in the heaviest fraction after separation.

[0098] The slurry catalyst is a catalyst that preferably contains at least one element selected from the group formed by Mo, Fe, Ni, W, Co, V, and Ru. These catalysts are generally monometallic or dimetallic (for example, by combining non-precious metal group VIIIB elements (Co, Ni, Fe) and group VIB elements (Mo, W)).

[0099] The catalyst used may be a powder of a different solid (e.g., natural ore, iron sulfate), a dispersed catalyst obtained from a water-soluble precursor ("water-soluble dispersed catalyst"), such as phosphomolybdic acid, ammonium molybdate, or a mixture of an oxide of Mo or Ni with aqueous ammonia.

[0100] Preferably, the catalyst used is derived from a precursor soluble in the organic phase ("oil-soluble dispersion catalyst"). The precursor is an organometallic compound, for example, a naphthenate of Mo, Co, Fe, or Ni, or a multicarbonyl compound of these metals, for example, a 2-ethylhexanoate of Mo or Ni, an acetylacetonate of Mo or Ni, or a salt of Mo or W of a C7-C12 fatty acid. They may be used in the presence of a surfactant to improve the dispersion of the metal when the catalyst is dimetallic.

[0101] The catalyst exists in the form of dispersed particles, which may be colloidal or otherwise, depending on the properties of the catalyst. Such precursors and catalysts that may be used in the method according to the present invention are widely described in the literature.

[0102] The catalyst concentration is expressed as metallic elements and is generally 1 to 10,000 ppm relative to the feedstock.

[0103] Generally, catalysts are prepared before being injected into the feedstock. The preparation method is tailored to the state and properties of the precursor. In all cases, the precursor is sulfurized (ex-situ or in-situ) to form a catalyst dispersed in the feedstock.

[0104] In the preferred case of an "oil-soluble" catalyst, in a typical method, the precursor is mixed with a carbon-based feedstock (which may be a portion of the feedstock to be processed, an externally supplied feedstock, a recycled portion, etc.), the mixture is optionally at least partially dried, and then, or simultaneously, sulfurized by adding a sulfur compound (preferably H2S) and heated. The preparation of these catalysts is described in the prior art.

[0105] After additives have been added during the preparation of the catalyst or slurryed catalyst, it can be injected into the reactor. These additives are described in the literature.

[0106] Suitable solid additives are mineral oxides, such as alumina, silica, Al / Si mixed oxides, and used supported catalysts (e.g., alumina and / or silica supported) containing at least one group VIII element (e.g., Ni, Co) and / or at least one group VIB element (e.g., Mo, W). A relevant example is the catalyst described in patent application US 2008 / 177124. Low hydrogen content (e.g., 4% hydrogen) carbon-based solids (possibly pre-treated), such as coke, may also be used. Mixtures of such additives may be used. Their particle size is preferably less than 1 mm. The content of any solid additives present at the entrance to the jet-bed hydrogenation-conversion reaction zone is 0–10% by weight, preferably 1–3% by weight, and the content of the catalyst solution is 0–10% by weight, preferably 0–1% by weight, relative to the weight of the injected feedstock.

[0107] When hydrogenation conversion step b) is performed in a flow-bed reactor, a filtration step is required to recover the catalyst before sending the hydrogenated effluent to step c).

[0108] (Moving bed hydrogenation conversion process b)) According to the third modification, the hydrogenation conversion step b) is carried out in a hydrogenation conversion reaction section including at least one moving bed reactor.

[0109] The feedstock and hydrogen can flow upward (counterflow) or downward (co-flow) in the moving bed reactor. The catalyst flows gradually from the top to the bottom by gravity, becoming a plug flow inside the catalyst zone. It is then removed from the bottom by any suitable means, such as an elevator (called a "lift"). In-line devices ensure semi-continuous catalyst renewal in the moving bed reactor: some of the spent catalyst is discharged at the bottom of the reactor, while fresh catalyst is introduced at the top of the reactor. Temperature is controlled in this respect by inter-reactor or intra-reactor quenching.

[0110] Preferably, instead of an extruded catalyst, a spherical catalyst with a diameter of 0.5 to 6 mm, preferably 1 to 3 mm, is used to obtain better fluidity. When the spent catalyst is removed from the bottom of the reactor, the entire catalyst bed moving in a plug flow moves downward by a height corresponding to the volume of the removed catalyst. The degree of expansion of the catalyst bed operated as a moving bed is advantageously less than 15%, preferably less than 10%, preferably less than 5%, and more preferably less than 2%. The degree of expansion is measured according to a method known to those skilled in the art.

[0111] The hydrogenation-conversion catalyst used in the moving bed of step b) of the method according to the present invention is a catalyst that preferably comprises a support, preferably an amorphous support, very preferably alumina, and at least one group VIII metal selected from nickel and cobalt, preferably nickel, wherein the group VIII element is preferably used in combination with at least one group VIB metal selected from molybdenum and tungsten, and preferably the group VIB metal is molybdenum. Preferably, the hydrogenation-conversion catalyst comprises nickel as the group VIII element and molybdenum as the group VIB element. The nickel content is expressed by the weight of nickel oxide (NiO) and is preferably 0.5% to 10% by weight, preferably 1% to 6% by weight, and the molybdenum content is expressed by the weight of molybdenum trioxide (MoO3) and is preferably 1% to 30% by weight, preferably 4% to 20% by weight, and the percentage is expressed as a weight percentage relative to the total weight of the catalyst. The catalyst is advantageously in the form of an extruded or beaded material. The catalyst may also advantageously contain phosphorus, preferably with a phosphorus pentoxide (P2O5) content of less than 20% by weight, more preferably less than 10% by weight, where the percentage is expressed as a weight percentage relative to the total weight of the catalyst. The catalyst may also be a catalyst supplemented with the above-mentioned organic compounds.

[0112] In yet another variation, the hydrogenation conversion step b) may be carried out in a hydrogenation conversion reaction section comprising any combination of at least one boiling bed reactor, at least one jet bed reactor and / or at least one moving bed reactor in any order.

[0113] Preferably, step b) is carried out in a hydrogenation-conversion reaction section including at least one boiling bed reactor.

[0114] (Separation step c)) According to the present invention, the processing method includes a separation step c), which is advantageously carried out in at least one washing / separation section, which is fed at least one hydrogenated effluent obtained from step b) and an aqueous solution to obtain at least one gaseous effluent, an aqueous effluent and a hydrocarbon effluent.

[0115] The gaseous effluent obtained at the end of step c) preferably contains hydrogen, preferably at least 90% by volume, and more preferably at least 95% by volume. Advantageously, the gaseous effluent may be recycled at least partially to selective hydrogenation steps a) and / or hydrogenation conversion steps b) and / or hydrogenation treatment steps e) and / or hydrocracking steps e'), the recycling system optionally including a purification section.

[0116] The aqueous effluent obtained at the end of step c) preferably contains an ammonium salt and / or hydrochloric acid. The aqueous effluent can be recycled back into step c).

[0117] In step b), ammonium chloride salts are produced by the reaction of chloride ions released by the hydrogenation and subsequent dissolution in water of chlorinated compounds, particularly those in the form of HCl, and ammonium ions produced by the hydrogenation and subsequent dissolution in water of nitrogenous compounds, particularly those in the form of NH3, provided in step b) and / or by the injection of amines. Separation step c) makes it possible to remove such ammonium chloride salts in particular, and therefore to limit the risk of clogging due to the deposition of ammonium chloride salts (particularly in the transfer lines and / or in the sections of the method of the present invention and / or the transfer line to the steam cracker). This also makes it possible to remove hydrochloric acid produced by the reaction of hydrogen ions with chloride ions.

[0118] Depending on the content of chlorinated compounds in the initial feedstock to be processed, a stream containing amines, such as monoethanolamine, diethanolamine, and / or monodiethanolamine, may be injected upstream of selective hydrogenation step a), between selective hydrogenation step a) and hydrogenation conversion step b), and / or between hydrogenation conversion step b) and separation step c), preferably upstream of selective hydrogenation step a) if present, to ensure a sufficient amount of ammonium ions to bind with the chloride ions formed during the hydrogenation conversion step, thereby limiting the formation of hydrochloric acid and thus limiting corrosion downstream of the separation section.

[0119] Advantageously, separation step c) upstream of the washing / separation section includes injecting an aqueous solution, preferably water, into the hydrogenated effluent obtained from step b), to at least partially dissolve the ammonium chloride salt and / or hydrochloric acid, thus improving the removal of chlorinated impurities and reducing the risk of clogging caused by the accumulation of ammonium chloride salt.

[0120] The temperature during separation step c) is advantageously 50–450°C, preferredly 100–440°C, and preferably 200–420°C. It is important to perform the step within this temperature range (and thus avoid overcooling the hydrogen-converted effluent) due to the risk of line clogging caused by ammonium chloride deposition. Advantageously, separation step c) is performed at a pressure close to that used in steps a) and / or b), preferably 1.0–20.0 MPa, to facilitate hydrogen recycling.

[0121] The washing / separation section of step c) may be carried out at least partially in a common or separate washing / separation facility, which is well known (separation vessels, pumps, heat exchangers, washing towers, etc., which may be operated at various pressures and temperatures).

[0122] In one embodiment of the present invention, separation step c) includes injecting an aqueous solution into the hydrogenated effluent obtained from step b), followed by a washing / separation section. The washing / separation section advantageously includes a separation phase for obtaining at least one aqueous effluent filled with an ammonium salt, a washed liquid hydrocarbon effluent, and a partially washed gaseous effluent. The aqueous effluent filled with an ammonium salt and the washed liquid hydrocarbon effluent may subsequently be separated in a decanting vessel to obtain the hydrocarbon effluent and the aqueous effluent. The partially washed gaseous effluent may, in parallel, be introduced into a washing tower, in which it flows countercurrently into an aqueous flow (preferably an aqueous flow of the same properties as the aqueous solution injected into the hydrogenated effluent), thereby removing at least partially, preferably completely, the hydrochloric acid contained in the partially washed gaseous effluent, thus making it possible to obtain the gaseous effluent (preferably containing hydrogen in nature) and an acidic aqueous flow. The aqueous effluent obtained from the decanting container may, optionally, be mixed with the acidic aqueous flow and, optionally, as a mixture with the acidic aqueous flow, be used in a water recycling circuit and fed to step c) separation of the aqueous solution and / or the aqueous flow in the washing tower upstream of the washing / separation section. The water recycling circuit may include a water supply and / or a purge to remove the basic solution and / or dissolved salts.

[0123] In another embodiment of the present invention, separation step c) may advantageously include a “high-pressure” washing / separation section, which is operated at a pressure close to that of selective hydrogenation step a) and / or hydrogenation conversion step b), preferably 1.0 to 20.0 MPa, to facilitate hydrogen recycling. This “high-pressure” section of step c) may be supplemented by a “low-pressure” section (preferably at a pressure generally of 0.5 to 10.0 MPa) to obtain a liquid hydrocarbon fraction intended to be sent to and processed in fractionation step d), which does not contain the gaseous portion dissolved at high pressure.

[0124] The gas fraction(s) obtained from separation step c) may be subjected to further purification(one or more) and separation(one or more) for the purpose of recovering at least one hydrogen-rich gas and light hydrocarbons, the hydrogen-rich gas may be recycled upstream to steps a) and / or b) and / or e) and / or e'), the light hydrocarbons being, among other things, ethane, propane and butane, which may be advantageously sent separately or as a mixture to one or more furnaces of steam cracking step h).

[0125] The hydrocarbon effluent obtained from separation step c) is sent partially or entirely, preferably entirely, to fractionation step d).

[0126] (Fractional process d)) The method according to the present invention includes a step of fractionating all or part, preferably all, of the hydrocarbon effluent obtained from step c) to obtain at least one gas stream, a hydrocarbon fraction containing a compound with a boiling point of 385°C or less, and a hydrocarbon fraction containing a compound with a boiling point greater than 385°C.

[0127] Step d) makes it particularly possible to remove gases dissolved in the liquid hydrocarbon effluent, such as ammonia, hydrogen sulfide, and light hydrocarbons containing 1 to 4 carbon atoms.

[0128] The pressure during fractionation step d) is advantageously 1.0 absolute MPa or less, preferably 0.1 to 1.0 absolute MPa.

[0129] According to one embodiment, step d) may be carried out in a section that advantageously includes at least one stripping column, which comprises a reflux circuit including a reflux vessel. The stripping column is fed the liquid hydrocarbon effluent obtained from step c) and a water vapor stream. The liquid hydrocarbon effluent obtained from step c) may optionally be heated before entering the stripping column. Thus, the lightest compounds are entrained at the top of the column and enter a reflux circuit including a reflux vessel where gas / liquid separation takes place. The gas phase containing the light hydrocarbons is withdrawn from the reflux vessel as a gas stream. Fractions containing compounds with boiling points below 385°C are advantageously withdrawn from the reflux vessel. Hydrocarbon fractions containing compounds with boiling points above 385°C are advantageously withdrawn at the bottom of the stripping column.

[0130] In other embodiments, fractionation step d) may include only a stripping column and a subsequent distillation column or distillation column.

[0131] Fractions containing compounds with a boiling point of 385°C or lower (naphtha fraction and diesel fraction) are sent, either whole or partially, to hydrogenation step e).

[0132] Fractions containing compounds with a boiling point above 385°C (unconverted oil) are advantageously recycled, at least partially, into the hydrogenation conversion process b). It can also be burned for heat and / or power generation.

[0133] A purge may be introduced into the recycling of the fraction obtained from step d) that contains a compound with a boiling point greater than 385°C. Depending on the operating conditions of the method, the purge may be 0 to 50% by weight, preferably 5% to 20% by weight, of the fraction obtained from step d).

[0134] The gas fraction(s) obtained from fractionation step d) may be further purified (once or more) and separated (once or more) for the purpose of recovering at least light hydrocarbons, particularly ethane, propane, and butane, which may be advantageously sent separately or as a mixture to one or more furnaces of steam cracking step h).

[0135] (Hydrogenation treatment process e)) According to the present invention, the treatment method includes a hydrogenation step e). Step e) is carried out in a hydrogenation reaction section using at least one fixed-bed reactor, the fixed-bed reactor containing n catalyst beds, where n is an integer of 1 or more, each containing at least one hydrogenation catalyst, and the hydrogenation reaction section is fed at least a portion of the hydrocarbon fraction containing a compound with a boiling point of 385°C or less obtained from step d) and a gas stream containing hydrogen to obtain a hydrogenated effluent.

[0136] Advantageously, step e) includes hydrogenation treatments, more specifically, hydrogenation reactions, such as hydrogenation, hydrodesulfurization, and hydrodenitrification of aromatic compounds, which are well known to those skilled in the art. Furthermore, hydrogenation and hydrodemetallation of olefins and residual halogenated compounds are carried out.

[0137] Advantageously, step e) is carried out in a hydrogenation reaction section comprising at least one, preferably 1 to 5, fixed-bed reactors. Each fixed-bed reactor contains n catalyst beds, where n is an integer of 1 or more, preferably 1 to 10, and preferably 2 to 5, and each of the beds (one or more) contains at least one, and preferably 10 or fewer, hydrogenation catalysts. If the reactor comprises several catalyst beds, i.e., at least two, preferably 2 to 10, and preferably 2 to 5 catalyst beds, the catalyst beds are arranged in series within the reactor.

[0138] The hydrogenation reaction section is advantageously supplied with at least a portion of the hydrocarbon fraction containing a compound with a boiling point of 385°C or less obtained from step d), and a gas stream containing hydrogen, to the level of the first catalyst bed of the first reactor during operation.

[0139] The hydrogenation reaction section of step e) may be fed at least a portion of the recycled flow (preferably obtained from any step g). The portion(s) or the entirety of the recycled flow may be introduced into the hydrogenation reaction section as a mixture with the hydrocarbon fraction obtained from step d) containing compounds with a boiling point of 385°C or less, or separately. The portion(s) or the entirety of the recycled flow may be introduced into one or more catalyst beds of the hydrogenation reaction section of step e). The introduction of at least a portion of the recycled flow is advantageous in diluting impurities still present in the hydrogenated effluent and in controlling the temperature in the catalyst bed(s) of the hydrogenation reaction section, which involves a highly exothermic reaction, particularly limiting the temperature rise.

[0140] The hydrogenation reaction temperature when the hydrogenation reaction section is operated is preferably 250 to 430°C, preferably 300 to 400°C, the partial pressure of hydrogen is 1.0 to 20.0 absolute MPa, preferably 3.0 to 15.0 absolute MPa, and the space velocity per hour (HSV) is 0.1 to 10.0 h. -1 Preferably 0.1 to 5.0 hours -1 Prioritizing 0.2-2.0h -1 Preferably 0.2 to 1.0h -1Therefore, according to the present invention, the "hydrogenation temperature" corresponds to the average temperature in the hydrogenation reaction section of step e). In particular, it corresponds to the weight-average bed temperature (WABT) in technical terms well known to those skilled in the art. The hydrogenation temperature is advantageously determined depending on the catalyst system, equipment and its configuration used. For example, the hydrogenation temperature (or WABT) is calculated by the following method.

[0141]

number

[0142] In the formula, T inlet : The temperature of the effluent at the inlet of the hydrogenation reaction section, where the boiling point is 385°C or lower. outlet : Temperature of the effluent at the outlet of the hydrogenation reaction section.

[0143] The space velocity per hour (HSV) is defined here as the ratio of the hourly volumetric flow rate of the hydrocarbon fraction containing compounds with a boiling point of 385°C or less obtained from step d) to the volume of the catalyst (one or more). The hydrogen coating in step e) is advantageously determined by the volume (m³) of the feed material supplied to step e). 3 ) Hydrogen per unit: 50-2000 Nm 3 Preferably, the volume (m³) of the raw material to be supplied to step e) 3 ) Hydrogen per unit: 100-1000 Nm 3 Preferably, the volume (m³) of the raw material to be supplied to step e) 3 ) Hydrogen per unit: 120-800 Nm 3 The hydrogen coverage is defined here as the ratio of the volumetric flow rate of hydrogen taken under standard temperature and pressure conditions to the volumetric flow rate of the feed material supplied to process e) (standard m of H2). 3 (Nm 3 (Described as) / m of fresh supply raw materials 3 ). The hydrogen may consist of supply hydrogen and / or recycled hydrogen specifically obtained from separation step c).

[0144] Preferably, an additional gas flow containing hydrogen is advantageously introduced, in particular, at the inlets of each reactor (especially those operating in series) and / or from the second catalyst bed of the hydrogenation reaction section to the inlets of each catalyst bed. These additional gas flows are also called cooling flows. They allow for temperature control in the hydrogenation reactor, where the associated reactions are generally highly exothermic.

[0145] Advantageously, the hydrogenation catalyst used in step e) may be selected from known demetallation, hydrogenation, or silicon capture catalysts, particularly those used for the treatment of petroleum fractions, and combinations thereof. Known demetallation catalysts are, for example, those described in Japanese Patents EP 0113297, EP 0113284, US 5221656, US 5827421, US 7119045, US 5622616, and US 5089463. Known hydrogenation catalysts are, for example, those described in Japanese Patents EP 0113297, EP 0113284, US 6589908, US 4818743, or US 6332976. Known silicon capture catalysts are, for example, those described in Japanese Patent Applications CN 102051202 and US 2007 / 080099.

[0146] In particular, the hydrogenation catalyst comprises a support, preferably a mineral support, and at least one metallic element having a hydrogenation-dehydrogenation function. The metallic element having a hydrogenation-dehydrogenation function preferably comprises at least one group VIII element and / or at least one group VIB element, wherein the at least one group VIII element is preferably selected from the group consisting of nickel and cobalt, and the at least one group VIB element is preferably selected from the group consisting of molybdenum and tungsten. The total content of oxides of metallic elements from group VIB and group VIII is preferably 0.1% to 40% by weight, and preferably 5% to 35% by weight, relative to the total weight of the catalyst. The weight ratio of group VIB metals (one or more) to group VIII metals (one or more), expressed as metal oxides, is preferably 1.0 to 20, and preferably 2.0 to 10. For example, the hydrogenation reaction section of step b) of this method includes a hydrogenation catalyst containing, on a mineral support, 0.5% to 10% by weight of nickel, preferably 1% to 8% by weight, expressed as nickel oxide NiO, relative to the total weight of the hydrogenation catalyst, and 1.0% to 30% by weight, preferably 3.0% to 29% by weight, of molybdenum and / or tungsten, expressed as molybdenum oxide MoO3 or tungsten oxide WO3, relative to the total weight of the hydrogenation catalyst.

[0147] The support for the hydrogenation catalyst is preferably selected from alumina, silica, silica-alumina, magnesia, clay, and mixtures thereof. The support may preferably contain dopant compounds, in particular oxides selected from boron oxides, especially boron trioxide, zirconia, ceria, titanium oxide, phosphorus pentoxide, and mixtures thereof. Preferably, the hydrogenation catalyst comprises an alumina support, preferably an alumina support 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 alumina, and preferably at least 0.001% by weight relative to the total weight of alumina. If boron trioxide (B2O5) is present, its concentration is less than 10% by weight relative to the weight of alumina, and preferably at least 0.001% by weight relative to the total weight of alumina. The alumina used may be, for example, γ (gamma) or η (eta) alumina.

[0148] The hydrogenation catalyst is, for example, in the form of an extruded product.

[0149] Advantageously, the specific surface area of ​​the hydrogenation catalyst used in step e) of this method is 250 m². 2 / g or more, preferably 300m 2 It is 1 / g or more. The specific surface area of ​​the hydrogenation treatment catalyst is preferably 800 m². 2 Less than or equal to / g, preferably 600m 2 / g or less, especially 400m 2 The specific surface area of ​​the hydrogenation catalyst is measured by the BET method. That is, the specific surface area is determined by nitrogen adsorption according to the standard ASTM D 3663-78, which was established from the Brunauer-Emmett-Teller method described in the periodical The Journal of the American Chemical Society, 60, 309 (1938). Such a specific surface area makes it possible to further improve the removal of contaminants, especially metals, such as silicon.

[0150] According to another aspect of the present invention, the hydrogenation catalyst also includes one or more organic compounds containing oxygen and / or nitrogen and / or sulfur. Such catalysts are often referred to by the term “additive catalyst.” Generally, the organic compounds are selected from compounds containing one or more chemical functional groups selected from carboxylic acids, alcohols, thiols, thioethers, sulfones, sulfoxides, ethers, aldehydes, ketones, esters, carbonates, amines, nitriles, imides, oximes, ureas, and amides, or compounds containing a furan ring, or sugars.

[0151] The preparation of catalysts for steps a), b), e), or e') is known and generally involves, in the case of supported catalysts, a step of impregnation onto a support with a group VIII metal and, if present, a group VIB metal, and optionally phosphorus and / or boron, followed by drying, and optionally calcination. In the case of additive catalysts, the preparation is generally carried out by simple drying and does not involve calcination after the introduction of the organic compound. The term “calcination” here means a heat treatment of 200°C or higher under air or an oxygen-containing gas. Prior to their use in the steps of this method, catalysts are generally subjected to sulfidation to form active species.

[0152] In a preferred embodiment of the present invention, the hydrogenation reaction section comprises several fixed-bed reactors, preferably 2 to 5, more preferably 2 to 4, each containing n catalyst beds, where n is an integer of 1 or more, preferably 1 to 10, preferably 2 to 5, and is advantageously operated in series and / or parallel and / or variable array (or PRS) and / or "swing" manner. Various arbitrary operating modes, PRS (or read-and-drag) mode and swing mode are well known to those skilled in the art and are advantageously as defined above. The advantage of a hydrogenation reaction section comprising several reactors is that it allows for optimized treatment of hydrocarbon fractions containing compounds with boiling points of 385°C or less obtained from step d), while simultaneously reducing the risk of clogging of one or more catalyst beds, and thus avoiding unit shutdown due to clogging.

[0153] According to a highly preferred embodiment of the present invention, the hydrogenation reaction section comprises at least one fixed-bed reactor, preferably consisting of one reactor or two reactors in series, and the fixed-bed reactor(s) (one or more) containing 1 to 5 catalyst beds are arranged in series and each contains 1 to 10 hydrogenation catalysts, of which at least one of the hydrogenation catalysts advantageously comprises a support and at least one metallic element, the at least one metallic element preferably comprises at least one group VIII element and / or at least one group VIB element, the group VIII element is preferably selected from nickel and cobalt, and the group VIB element is preferably selected from molybdenum and tungsten.

[0154] In some cases, step e) may include a heating section located upstream of the hydrogenation reaction section, in which the hydrocarbon fraction obtained from step d) containing compounds with a boiling point of 385°C or less is heated to a temperature suitable for hydrogenation, i.e., a temperature of 250 to 430°C. The optional heating section may therefore include one or more exchangers (preferably enabling heat exchange between the hydrocarbon fraction obtained from step d) containing compounds with a boiling point of 385°C or less and the hydrogenated effluent) and / or a preheating furnace.

[0155] Hydrogenation step e) advantageously enables optimized treatment of hydrocarbon fractions obtained from step d) that contain compounds with a boiling point of 385°C or less. This makes it possible to remove, in particular, residual impurities, especially sulfur compounds and nitrogen compounds, as well as residual metals.

[0156] (Hydrocrack step e') (Optional) According to one variation, the method of the present invention may include a hydrocracking step e'). This step is performed either immediately after the hydrocracking step e) or after step f) of separation of the heavy fraction (diesel fraction).

[0157] A fraction containing compounds with a boiling point of 385°C or less includes a fraction containing compounds with a boiling point of 175°C or less (naphtha fraction) and a fraction containing compounds with a boiling point greater than 175°C and 385°C or less (diesel fraction). If it is desirable to minimize the yield of the diesel fraction and maximize the yield of the naphtha fraction, the diesel fraction may be converted to the naphtha fraction by hydrocracking, or furthermore, a portion of the heavy naphtha fraction may be converted to light naphtha. Light naphtha is generally a fraction favored by steam cracking units.

[0158] Therefore, the method of the present invention may include a hydrocracking step e'). This step is carried out in a hydrocracking reaction section, using at least one fixed bed containing n catalyst beds, where n is an integer of 1 or more, each containing at least one type of hydrocracking catalyst, the hydrocracking reaction section is fed a diesel fraction containing the hydrotreated effluent obtained from step e) and / or a compound with a boiling point greater than 175°C and less than or equal to 385°C obtained from step f), and a gas stream containing hydrogen, the temperature when the hydrocracking reaction section is operated is 250 to 450°C, the partial pressure of hydrogen is 1.5 to 20.0 absolute MPa, and the space velocity per hour is 0.1 to 10.0 h -1 This yields hydrocracking-treated effluent, which is then sent to separation step f).

[0159] Advantageously, step e') includes a hydrocracking reaction well known to those skilled in the art, more specifically, enabling the conversion of heavy compounds contained in the hydrogenated effluent obtained from step b), such as compounds with boiling points greater than 175°C, to compounds with boiling points 175°C or less. Other reactions, such as hydrogenation, hydrodemetallation, hydrodesulfurization, hydrodenitrification of olefins or aromatic compounds, may follow.

[0160] Advantageously, step e') is carried out in a hydrocracking reaction section, which includes at least one, preferably 1 to 5, fixed beds, each of which contains n catalyst beds, where n is an integer of 1 or more, preferably 1 to 10, and preferably 2 to 5, and each of the beds (one or more) contains at least one, preferably 10 or fewer, hydrocracking catalysts.

[0161] The hydrogenation step e) and the hydrocracking step e') may, advantageously, be carried out in the same reactor or in different reactors. If they are carried out in the same reactor, the reactor comprises several catalyst beds, the first catalyst bed comprising one or more hydrogenation catalysts, and the subsequent catalyst beds comprising one or more hydrocracking catalysts.

[0162] The hydrogenation temperature when the hydrogenocrack reaction section is advantageously operated is 250 to 450°C, preferably 320 to 430°C, the partial pressure of hydrogen at which point is 1.5 to 20 absolute MPa, and the space velocity per hour (HSV) at which point is 0.1 to 10.0 h. -1 Preferably 0.1 to 5.0 hours -1 Prioritizing 0.2-4 hours -1 Therefore, according to the present invention, the "hydrocracking temperature" corresponds to the average temperature in the hydrocracking reaction section of step c). In particular, it corresponds to the weight-average bed temperature (WABT), according to the terminology well known to those skilled in the art. The hydrocracking temperature is advantageously determined depending on the catalyst system, equipment and its configuration used. For example, the hydrocracking temperature (i.e., WABT) is calculated by the following method:

[0163]

number

[0164] The space velocity per hour (HSV) is defined here as the ratio of the hourly volumetric flow rate of the hydrogenated effluent obtained from step e) to the volume of the catalyst (one or more). The hydrogen coating in step e') is advantageously determined by the volume (m³) of the feed material supplied to step e'). 3 ) Hydrogen per unit: 80-2000 Nm 3 Preferably, the volume (m³) of the raw material to be supplied to step e') 3 ) Hydrogen per unit: 200-1800 Nm 3 The hydrogen coverage is defined here as the ratio of the volumetric flow rate of hydrogen taken under standard temperature and pressure conditions to the volumetric flow rate of the feed material supplied to process e') (volume of feed material (m³). 3 ) Standard H2 m per unit 3 (Nm 3(This is written as follows). The hydrogen may consist of supply hydrogen and / or recycled hydrogen specifically obtained from separation steps c) and d).

[0165] Preferably, an additional gas flow containing hydrogen is advantageously introduced, particularly at the inlets of each reactor (especially those operating in series) and / or from the second catalyst bed of the hydrocracking reaction section to the inlets of each catalyst bed. These additional gas flows are also called cooling flows. They allow for temperature control in the hydrocracking reactor, where the associated reactions are generally highly exothermic.

[0166] The hydrocracking step e') may be carried out in one or two steps. If it is carried out in two steps, the effluent from the first hydrocracking step e') can be separated to obtain a fraction (diesel fraction) containing compounds with a boiling point greater than 175°C, which is then introduced into the second hydrocracking step. This configuration is particularly suitable when it is desired to produce only a naphtha fraction. The operating conditions and catalysts used in the two hydrocracking steps may be the same or different.

[0167] The operating conditions used in step e') of the method according to the present invention generally make it possible to obtain a conversion rate per pass to a product having a minimum of 80% by volume of compounds with a boiling point of 175°C or less, preferably less than 160°C, preferably less than 150°C: more than 15% by weight, more preferably 20% to 80% by weight. When the method is carried out in two hydrocracking steps, the conversion rate per pass in the second step is moderately maintained to maximize the selectivity of the naphtha fraction toward compounds (with a boiling point of 175°C or less, particularly between 80°C and 175°C or less). The conversion rate per pass is limited by the use of a high recycle ratio across the second hydrocracking step loop. This ratio is defined as the ratio of the feed flow rate in step f) to the feed flow rate in step a); preferably this ratio is 0.2 to 4, preferably 0.5 to 2.5.

[0168] The hydrocracking step e') does not necessarily enable the conversion of all compounds with boiling points above 175°C (diesel fraction) to compounds with boiling points below 175°C (naphtha fraction). After fractionation step f), a greater or lesser proportion of compounds with boiling points above 175°C may remain. To increase the conversion rate, at least a portion of this unconverted fraction can be recycled to step e') as described below. Another portion can be purged. Depending on the operating conditions of the method, the purging may be 0 to 10% by weight, preferably 0.5% to 5% by weight, of the fraction containing compounds with boiling points above 175°C relative to the incoming feedstock.

[0169] According to the present invention, the hydrocracking step e') is carried out in the presence of at least one hydrocracking catalyst.

[0170] The hydrocracking catalyst (one or more types) used in the hydrocracking step e') is a conventional hydrocracking catalyst known to those skilled in the art, and is a bifunctional type that combines an acidic functional group with a hydrogenation-dehydrogenating functional group and optionally at least one binder matrix. The acidic functional group has a large surface area (generally 150-800 m²) with surface acidity. 2 The carrier having ( / g) is provided by, for example, halogenated (particularly chlorinated or fluorinated) alumina, a combination of boron and aluminum oxides, amorphous silica-alumina and zeolites. The hydrogenation-dehydrogenation functional group is provided by at least one metal from Group VIB of the periodic table and / or at least one metal from Group VIII.

[0171] Preferably, the hydrocracking catalyst (one or more types) used in step e') contains a hydrodehydrogenating functional group comprising at least one metal from Group VIII, preferably selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, and platinum, and preferably from cobalt and nickel. Preferably, the catalyst (one or more types) also contains at least one metal from Group VIB, preferably selected from chromium, molybdenum, and tungsten, either alone or in a mixture, and preferably from molybdenum and tungsten. Hydrodehydrogenating functional groups of the type NiMo, NiMoW, or NiW are preferred.

[0172] Preferably, the content of metals from Group VIII in the hydrocracking catalyst (one or more types) is advantageously 0.5% to 15% by weight, preferably 1% to 10% by weight, and the percentage is expressed as the weight percentage of oxides relative to the total weight of the catalyst.

[0173] Preferably, the content of metals from Group VIB in the hydrocracking catalyst (one or more types) is advantageously 5% to 35% by weight, preferably 10% to 30% by weight, and the percentage is expressed as the weight percentage of oxides relative to the total weight of the catalyst.

[0174] The hydrocracking catalyst (one or more types) used in step e') may optionally include at least one promoter element selected from the group formed by phosphorus, boron, and silicon, which is deposited on the catalyst; optionally at least one element from group VIIA (preferably chlorine and fluorine); optionally at least one element from group VIIB (preferably manganese); and optionally at least one element from group VB (preferably niobium).

[0175] Preferably, the hydrocracking catalyst (one or more types) used in step e') comprises at least one amorphous or low-crystallinity porous mineral matrix of an oxide type, selected individually or as a mixture from alumina, silica, silica-alumina, aluminate, alumina-boron oxide, magnesia, silica-magnesia, zirconia, titanium oxide, or clay, preferably selected individually or as a mixture from alumina or silica-alumina.

[0176] Preferably, the silica-alumina contains more than 50% by weight of alumina, preferably more than 60% by weight of alumina.

[0177] Preferably, the hydrocracking catalyst (one or more) used in step e') may include, in some cases, zeolites selected from Y zeolite, preferably USY zeolite, either alone or in combination with other zeolites, either alone or as a mixture, from among beta, ZSM-12, IZM-2, ZSM-22, ZSM-23, SAPO-11, ZSM-48, or ZBM-30 zeolites. Preferably, the zeolite is a single USY zeolite.

[0178] When the catalyst contains zeolite, the zeolite content in the hydrocracking catalyst (one or more types) is advantageously 0.1% to 80% by weight, preferably 3% to 70% by weight, and the percentage is expressed as the percentage of zeolite relative to the total weight of the catalyst.

[0179] A suitable catalyst comprises, and preferably consists of, at least one metal from Group VIB, optionally at least one non-precious metal from Group VIII, at least one promoter element, preferably phosphorus, at least one Y zeolite, and at least one alumina binder.

[0180] A more preferable catalyst comprises, and preferably consists of, nickel, molybdenum, phosphorus, USY zeolite, possibly beta zeolite, and alumina.

[0181] Other preferred catalysts include, and preferably consist of, nickel, tungsten, alumina, and silica-alumina.

[0182] Other suitable catalysts include, and preferably consist of, nickel, tungsten, USY zeolite, alumina, and silica-alumina.

[0183] The hydrogenocrack catalyst is, for example, in the form of an extruded product.

[0184] According to another aspect of the present invention, the above-described hydrocracking catalyst also includes one or more organic compounds containing oxygen and / or nitrogen and / or sulfur. Such catalysts are often referred to as “additive catalysts.” Generally, the organic compounds are selected from compounds containing one or more chemical functional groups selected from carboxylic acids, alcohols, thiols, thioethers, sulfones, sulfoxides, ethers, aldehydes, ketones, esters, carbonates, amines, nitriles, imides, oximes, ureas, and amides, or compounds containing furan rings, or sugars.

[0185] (Separation process f)) According to the present invention, the treatment method includes a separation step f), to which hydrogenated effluent obtained from step e) or hydrogen-cracked effluent obtained from any step e') is fed, and at least one gaseous effluent and a hydrogenated liquid hydrocarbon effluent are obtained.

[0186] The separation section of step f) is advantageously operated in well-known separation equipment (separation vessels, pumps, heat exchangers, stripping columns, distillation columns, etc., which may be operated at various pressures and temperatures).

[0187] The gaseous effluent obtained at the end of step f) preferably contains hydrogen, preferably at least 90% by volume, and preferably at least 95% by volume. Advantageously, the gaseous effluent may be recycled at least partially to a selective hydrogenation step a) and / or a hydrogenation conversion step b) and / or a hydrogenation treatment step e) and / or an optional hydrocracking step e'), the recycling system optionally including a purification section.

[0188] The gaseous effluent obtained at the end of step f) may include light hydrocarbons, in particular ethane, propane, and butane, and may be advantageously sent separately or as a mixture to one or more furnaces of the steam decomposition step h).

[0189] Step f) makes it particularly possible to remove gases dissolved in the liquid hydrocarbon effluent, such as ammonia, hydrogen sulfide, and light hydrocarbons containing 1 to 4 carbon atoms.

[0190] The pressure under which fractionation step f) is advantageously carried out is 1.0 absolute MPa or less, preferably 0.1 to 1.0 absolute MPa.

[0191] According to one embodiment, step f) may be carried out in a section that advantageously includes at least one stripping column, which comprises a reflux circuit including a reflux vessel. The stripping column is fed the hydrogenated effluent and steam stream obtained from step e). The hydrogenated effluent obtained from step e) may optionally be heated before entering the stripping column. In this way, the lightest compounds are entrained at the top of the column and enter the reflux circuit including a reflux vessel, where gas / liquid separation takes place. The gaseous phase containing light hydrocarbons is withdrawn from the reflux vessel as a gas stream. The hydrogenated liquid hydrocarbon effluent (naphtha fraction and diesel fraction), which is a fraction containing hydrogenated compounds with a boiling point of 385°C or less, is advantageously withdrawn at the bottom of the stripping column.

[0192] In other embodiments, separation step f) may include a stripping column followed by a distillation column, or a distillation column alone.

[0193] In certain embodiments, separation step f) may include fractionation, which, in addition to the gas flow, allows for obtaining a naphtha fraction containing compounds with a boiling point of 175°C or less, preferably 80 to 175°C, and a diesel fraction containing compounds with a boiling point greater than 175°C and less than 385°C.

[0194] The naphtha fraction may be sent whole or partially to a steam cracking unit and / or a naphtha pool obtained from conventional petroleum feedstocks; it may also be sent to a recycling process g).

[0195] The diesel fraction may be sent, in whole or in part, to either a steam cracking unit or a pool of jet fuel and diesel obtained from conventional petroleum feedstocks, or to a hydrocracking process e') if one exists.

[0196] In another specific embodiment, a naphtha fraction containing compounds with a boiling point of 175°C or less is fractionated to give a heavy naphtha fraction containing compounds with a boiling point of 80 to 175°C and a light naphtha fraction containing compounds with a boiling point of less than 80°C. At least a portion of the heavy naphtha fraction may be sent to an aromatics complex, which includes at least one step of naphtha modification for the purpose of producing aromatic compounds. The heavy naphtha fraction may be sent at least in part to the steam decomposition step h) described below. According to this embodiment, at least a portion of the light naphtha fraction is sent to the steam decomposition step h) described below.

[0197] (Step g) (Optional) is a process to recycle the hydrogenated liquid hydrocarbon effluent obtained from (step f). The method according to the present invention may include a recycling step g), in which a portion of the hydrogenated liquid hydrocarbon effluent obtained from the separation step f) is recovered to form a recycling stream, which is sent upstream or directly to at least one of the reaction steps of the method according to the present invention, in particular to any selective hydrogenation step a) and / or hydrogenation conversion step b) and / or hydrogenation step e). In some cases, a portion of the recycling stream may be sent to any pretreatment step a0).

[0198] Preferably, at least a portion of the hydrogenated liquid hydrocarbon effluent obtained from separation step f) is fed to hydrogenation step e).

[0199] Advantageously, the amount of the recycled flow is adjusted so that the weight ratio between the recycled flow and the feed material containing pyrolysis oil, i.e., the feed material to be processed supplied to the entire method, is 10 or less, preferably 5 or less, and more preferably 0.001 or more, preferably 0.01 or more, and preferably 0.1 or more. Much more preferably, the amount of the recycled flow is adjusted so that the weight ratio between the recycled flow and the feed material containing pyrolysis oil is 0.2 to 5.

[0200] Depending on the raw materials being processed, recycling a portion of the resulting product into at least one of the reaction steps of the method according to the present invention or upstream of it is advantageous that, in reaction steps (one or more) where the associated reactions may be highly exothermic, it is possible to, firstly, dilute impurities and, secondly, control the temperature.

[0201] According to a preferred embodiment of the present invention, a method for processing a feedstock containing pyrolysis oil is a series of steps as follows: b) Hydrogenation conversion, c) separation; d) Fractionation e) Hydrogenation treatment, f) separation; Preferably comprising, and preferably consisting of, in a given order, an effluent, at least a portion thereof, suitable for treatment in a steam decomposition unit.

[0202] According to a second preferred embodiment of the present invention, a method for processing a feedstock containing pyrolysis oil comprises the following series of steps: b) Hydrogenation conversion, c) separation; d) Fractionation of at least a portion of a hydrocarbon fraction containing compounds with a boiling point greater than 385°C, involving recycling to step b), e) Hydrogenation treatment, f) separation; Preferably comprising, and preferably consisting of, in a given order, an effluent, at least a portion thereof, suitable for treatment in a steam decomposition unit.

[0203] According to a third preferred embodiment of the present invention, a method for processing a feedstock containing pyrolysis oil comprises the following series of steps: b) Hydrogenation conversion, c) separation; d) Fractionation of at least a portion of a hydrocarbon fraction containing compounds with a boiling point greater than 385°C, involving recycling to step b), e) Hydrogenation treatment, e') Hydrocracking, f) Separation Preferably comprising, and preferably consisting of, in a given order, an effluent, at least a portion thereof, suitable for treatment in a steam decomposition unit.

[0204] According to a fourth preferred embodiment of the present invention, a method for processing a feedstock containing pyrolysis oil of plastics and / or SRF comprises the following series of steps: a) Selective hydrogenation, b) Hydrogenation conversion, c) separation; d) Fractionation of at least a portion of a hydrocarbon fraction containing compounds with a boiling point greater than 385°C, involving recycling to step b), e) Hydrogenation treatment, e') Hydrocracking, f) separation; g) Recycling of at least some of the hydrogenated liquid hydrocarbon effluent obtained from step f) to steps a) and / or b) and / or e), Preferably comprising, and preferably consisting of, in a given order, an effluent, at least a portion thereof, suitable for treatment in a steam decomposition unit.

[0205] The hydrogenated liquid hydrocarbon effluent or a portion thereof obtained by the treatment of the pyrolysis oil by the method of the present invention has a composition that can be adapted to the specifications for feedstock entering the steam cracking unit. In particular, the composition of the hydrocarbon effluent or the hydrocarbon stream(s) is preferably as follows: - The total content of metallic elements is 5.0 ppm by weight or less, preferably 2.0 ppm by weight or less, more preferably 1.0 ppm by weight or less, and more preferably 0.5 ppm by weight or less, and accordingly: - The iron (Fe) content is 100 ppb by weight or less. - The silicon (Si) element content is 1.0 ppm by weight or less, preferably 0.6 ppm by weight or less, and - The sulfur content is 500 ppm by weight or less, preferably 200 ppm by weight or less. - The nitrogen content is 100 ppm by weight or less, preferably 50 ppm by weight or less, preferably 5 ppm by weight or less. - The total content of chlorine element is 10 ppm by weight or less, preferably less than 1.0 ppm by weight. - The asphaltene content is 5.0 ppm by weight or less. - The content of olefin compounds (monoolefins and diolefins) is 5.0% by weight or less, preferably 2.0% by weight or less, and preferably 0.1% by weight or less.

[0206] The content is given as relative weight concentration, weight percentage (%), parts per million (ppm), or parts per billion (ppb) relative to the total weight of the flow under consideration.

[0207] The method according to the present invention makes it possible to treat SRF and / or plastic pyrolysis oil to obtain an effluent that can be injected whole or partially into a steam decomposition unit.

[0208] (Steam decomposition process h) (Optional) The hydrogenated liquid hydrocarbon effluent obtained from step f) may be sent, in whole or in part, to the steam cracking step h).

[0209] Advantageously, the gas fraction(s) obtained from separation steps c) and / or f) and containing ethane, propane, and butane may be sent whole or partially to steam cracking step h).

[0210] The steam decomposition step h) is preferably carried out in at least one pyrolysis furnace at a temperature of 700 to 900°C, preferably 750 to 850°C, and under a pressure of 0.05 to 0.3 relative MPa. The residence time of the hydrocarbon compound is generally 1.0 second (denoted as s) or less, preferably 0.1 to 0.5 s. Steam is preferably introduced upstream of any steam decomposition step h) after separation (or fractionation). The amount of water introduced (preferably in the form of steam) is preferably 0.3 to 3.0 kg of water per kg of the weight (kg) of the hydrocarbon compound entering step h). Any step h) is preferably carried out in a plurality of parallel pyrolysis furnaces to adapt the operating conditions to the various flows supplied to step h), in particular those obtained from steps c) and / or f), and / or to control the decoking time of the tubes. The furnaces include one or a plurality of tubes arranged in parallel. The furnaces may also represent a group of furnaces operating in parallel. For example, the furnace may be dedicated to the decomposition of naphtha fractions containing compounds with boiling points below 175°C.

[0211] Evaporates from various steam cracking furnaces are generally subjected to separation for the purpose of recombining and then constituting the effluent. It is understood that the steam cracking process h) includes not only the steam cracking furnace but also sub-processes related to steam cracking that are well known to those skilled in the art. These sub-processes may include, among other things, heat exchangers, columns and catalytic reactors and recycling to the furnace. Columns generally allow for the fractionation of the effluent for the purpose of recovering at least one light fraction containing hydrogen and compounds containing 2 to 5 carbon atoms, a fraction containing pyrolysis gasoline, and optionally, a fraction containing pyrolysis oil. Columns allow for the separation of various components of the fractionated light fractions to recover at least one fraction rich in ethylene (C2 fraction), a fraction rich in propylene (C3 fraction), and optionally a fraction rich in butene (C4 fraction). Catalytic reactors, among other things, allow for the selective hydrogenation of the C2, C3, and even C4 fractions and the pyrolysis gasoline. Saturated compounds, particularly those containing 2 to 4 carbon atoms, are advantageously recycled into steam cracking furnaces to increase the overall yield of olefins.

[0212] This steam decomposition step h) makes it possible to obtain at least one effluent containing olefins containing 2, 3, and / or 4 carbon atoms (i.e., C2, C3, and / or C4 olefins) in a satisfactory content, particularly at 30% by weight or more, especially 40% by weight or more, and even 50% by weight or more, of the total weight of olefins containing 2, 3, and 4 carbon atoms relative to the weight of the steam decomposition effluent under consideration. The C2, C3, and C4 olefins may then be advantageously used as monomers for polyolefins.

[0213] According to one or more preferred embodiments of the present invention, a method for processing a feedstock containing SRF and / or plastic pyrolysis oil, used separately or in combination, comprises, and preferably consists of, the following series of steps, preferably in a given order: b) Hydrogenation conversion, c) separation; d) Fractionation, e) Hydrogenation treatment, f) separation; h) Decomposition by water vapor.

[0214] In a preferred form, a method for processing a feedstock containing SRF and / or plastic pyrolysis oil comprises, and preferably consists of, the following series of steps, preferably in a given order: a) Selective hydrogenation, b) Hydrogenation conversion, c) separation; d) Fractionation of at least a portion of a hydrocarbon fraction containing compounds with a boiling point greater than 385°C, involving recycling to step b), e) Hydrogenation treatment, e') Hydrocracking, f) separation; h) Steam decomposition of at least the remaining portion of the hydrogenated liquid hydrocarbon effluent obtained from step f).

[0215] (Analysis methods used) Various analytical methods and / or standards used to determine the characteristics of different flows, particularly the feedstock and spills to be processed, are known to those skilled in the art. These are listed below, in particular, for informational purposes. Other reputable equivalent methods may also be used, including, among other, equivalent IP, EN, or ISO methods.

[0216] [Table 1]

[0217] (1) The MAV method is described in the following article: 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, pages 57-68 (List of drawings) The information regarding the elements referenced in Figure 1 will enable a better understanding of the present invention, but the invention is not limited to the specific embodiments shown in Figure 1. The various embodiments presented may be used individually or in combination with each other, and there are no restrictions on the combinations.

[0218] Figure 1 shows a scheme of a specific embodiment of the method of the present invention, and includes the following: - Optional step a) of selective hydrogenation of hydrocarbon feedstock obtained from pyrolysis; carried out in at least one fixed-bed reactor in the presence of hydrogen-rich gas (2) and optionally an amine supplied by a flow (3), the fixed-bed reactor comprising at least one selective hydrogenation catalyst, and obtaining effluent (4); - Step b) Hydrogenation conversion of the effluent (4) obtained from step a); carried out in at least one boiling bed, jet bed and / or moving bed reactor in the presence of hydrogen (5), the reactor comprising at least one hydrogenation conversion catalyst, to obtain hydrogenation-converted effluent (6); - Step c of separating the effluent (6) is carried out in the presence of a washing aqueous solution (7), which allows obtaining at least one fraction (8) containing hydrogen, an aqueous fraction (9) containing dissolved salt, and a hydrocarbon liquid fraction (10); - Step d) fractionation of the liquid hydrocarbon fraction (10); enabling the acquisition of at least one gaseous fraction (11), a hydrocarbon fraction (12) containing a compound with a boiling point of 385°C or less, and a hydrocarbon fraction (13) containing a compound with a boiling point greater than 385°C, wherein the hydrocarbon fraction (13) is preferably recycled at least partially to step b); - Step e) Hydrogenation of at least a portion of the hydrocarbon fraction (12) obtained from step d) containing a compound with a boiling point of 385°C or less; carried out in at least one fixed-bed reactor containing at least one hydrogenation catalyst in the presence of hydrogen (14) to obtain hydrogenated effluent (15); - Step f of separating the spill (15): Allows obtaining at least one fraction (16) containing hydrogen and a hydrogenated liquid hydrocarbon spill (17).

[0219] At the end of step f), at least a portion of the hydrogenated liquid hydrocarbon (17) is sent to a steam decomposition method (not indicated).

[0220] In some cases, a portion of the hydrogenated liquid hydrocarbon effluent (17) constitutes a recycling flow (17a), (17b), and (17c), which are fed to processes a) and / or b) and / or e), respectively.

[0221] Only the main processes, along with the main flow, are shown in Figure 1 to enable a better understanding of the present invention. Even if not all equipment items required for functionality (containers, pumps, exchangers, furnaces, columns, etc.) are shown, it is clearly understood that they are present. It is also understood that the above hydrogen-rich gas flow (supply or recycle) may be injected into the inlet of each reactor or catalyst bed or between two reactors or two catalyst beds. Means well known to those skilled in the art for purifying and recycling hydrogen may be used.

[0222] (Examples) (Example 1: Conforms to the present invention) The feedstock (1) processed in this method is SRF pyrolysis oil and has the characteristics indicated in Table 2.

[0223]

Table 2

[0224] The feedstock (1) is directly fed (without the (optional hydrogenation step a)) to the hydroconversion step b). The hydroconversion step b) is carried out in a fluidized bed under the conditions indicated in Table 3 in the presence of hydrogen (5) and an alumina-supported NiMo type hydrotreating catalyst.

[0225]

Table 3

[0226] The effluent (6) obtained from the hydroconversion step b) is sent to a separation step c) and then to a fractionation step d). Table 4 gives the yields of the various fractions obtained at the end of the fractionation step d) relative to the feedstock (1) entering the chain of this method.

[0227]

Table 4

[0228] The liquid fractions (naphtha fraction and diesel fraction) containing compounds with a boiling point of 385 °C or lower are then sent to a hydrotreating step e) under the conditions shown in Table 5 in the presence of hydrogen and an alumina-supported NiMo type hydrotreating catalyst.

[0229]

Table 5

[0230] The effluent (17) obtained from the hydrotreating step e) is subjected to a separation and fractionation step f).

[0231] Table 6 shows the overall yields relative to the feedstock (1) entering the chain of this method for the various fractions obtained at the end of step f) of separation and fractionation (including stripping and distillation columns).

[0232] [Table 6]

[0233] The compounds H2S and NH3 are removed, mainly in the form of salts, into the aqueous phase removed in separation step d).

[0234] Table 7 shows the characteristics of the liquid fractions obtained after the separation and fractionation step f) at PI-175°C and 175°C-385°C.

[0235] [Table 7]

[0236] Both the PI-175℃ and 175℃-385℃ liquid fractions have compositions that are compatible with the steam decomposition unit, for the following reasons: - They have very low concentrations of elemental chlorine (undetectable and 25 wt ppb, respectively), which is below the limit required for steam cracking feedstock; - The metal content, especially iron (Fe), is very low (metal content is undetectable in the PI-175°C fraction and <1 ppm by weight in the 175°C-385°C fraction; Fe content is undetectable in the PI-175°C fraction and 25 ppb by weight in the 175°C-385°C fraction), below the limits required for steam decomposition feedstock (≤5.0 ppm by weight for metals, very preferably ≤1 ppm by weight; ≤100 ppb by weight for Fe); - Finally, they contain sulfur (<2 wt ppm for the PI-175°C fraction and <2 wt ppm for the 175°C - 385°C fraction) and nitrogen (<5 wt ppm for the PI-175°C fraction and <10 wt ppm for the 175°C - 385°C fraction), and these contents are far lower than the limits required for the steam cracking feedstock (≤500 wt ppm for S and N, preferably ≤200 wt ppm).

[0237] The obtained liquid fractions of PI-175°C and 175°C - 385°C are thus subsequently sent to the steam cracking step h) (see Table 8).

[0238]

Table 8

[0239] The effluents from various steam crackers are subjected to a separation step. The separation step enables the recycling of saturated compounds to the steam cracker and the generation of the yields presented in Table 9 (yield = mass % of the product relative to the mass of the PI-175°C and 175°C - 385°C fractions upstream of the steam cracking step, expressed as wt %).

[0240] [[ID=ST21]]

Table 9

[0241] Considering the yields obtained for the liquid fractions of PI-175°C and 175°C - 385°C at the outlet of the hydroconversion and hydrotreatment steps during the pyrolysis oil treatment method (see Table 6), it is possible to determine the overall yield of the method for the product obtained from the steam cracking step h) relative to the feedstock (1) entering the chain of the method relative to the initial feedstock of the SRF pyrolysis oil type introduced in step a).

[0242]

Table 10

[0243] When fractions at PI-175°C and 175-385°C are supplied to a steam decomposition unit, the method according to the present invention makes it possible to achieve overall mass yields of ethylene and propylene of 28.7% and 15.1%, respectively, relative to the mass of the initial feedstock of the pyrolysis oil type.

[0244] Furthermore, a specific series of steps upstream of the steam decomposition process makes it possible to limit coke formation and avoid corrosion problems that would arise if chlorine were not removed.

[0245] (Example 2: Conforms to the present invention) The raw material (1) processed in this method is a plastic pyrolysis oil and has the characteristics indicated in Table 11.

[0246] [Table 11]

[0247] The raw material (1) is subjected to selective hydrogenation step a). Selective hydrogenation step a) is carried out in a fixed-bed reactor under the conditions indicated in Table 12 in the presence of hydrogen (2) and an alumina-supported NiMo type selective hydrogenation catalyst.

[0248] [Table 12]

[0249] At the end of selective hydrogenation step a), the diolefin content in the feedstock was significantly reduced.

[0250] The effluent (4) obtained from the selective hydrogenation step a) is directly subjected to the hydrogenation conversion step b) without separation. The hydrogenation conversion step b) is carried out in a boiling bed under the conditions shown in Table 13, in the presence of hydrogen (5) and an alumina-supported NiMo type hydrogenation catalyst.

[0251] [Table 13]

[0252] The effluent (6) obtained from hydrogenation step b) is sent to separation step c) and then to fractionation step d). Table 14 shows the yields of the various fractions obtained at the end of fractionation step d) relative to the feed material (1) entering the chain of this method.

[0253] [Table 14]

[0254] Liquid fractions containing compounds with a boiling point of 385°C or lower (naphtha fraction PI -150°C and diesel fraction 150°C+) are then sent to hydrogenation step e) under the conditions shown in Table 15 in the presence of hydrogen and an alumina-supported NiMo type hydrogenation catalyst.

[0255] [Table 15]

[0256] The effluent (17) obtained at the end of hydrogenation step e) is subjected to separation and fractionation step f).

[0257] Table 16 shows the overall yields for the various fractions obtained at the end of the separation and fractionation step f) (including the stripping column and distillation column) relative to the feedstock (1) entering the chain of this method.

[0258] [Table 16]

[0259] The compounds H2S and NH3 are removed, mainly in the form of salts, into the aqueous phase which is removed in separation step d).

[0260] Table 17 shows the characteristics of the liquid fractions at PI-150°C and 150°C+ obtained after the separation and fractionation step f).

[0261] [Table 17]

[0262] Both the PI-150℃ and 150℃+ liquid fractions have compositions suitable for use in a water vapor decomposition unit, for the following reasons: - They contain no olefins (monoolefins and diolefins); - They have very low concentrations of elemental chlorine (undetectable and 25 wt ppb, respectively); below the limits required for steam cracking feedstock; - The metal content, especially iron (Fe), is also very low (metal content is undetectable in the PI-150°C fraction and <1 ppm by weight in the 150°C+ fraction; Fe content is undetectable in the PI-150°C fraction and <50 ppb by weight in the 150°C+ fraction); these are below the limits required for steam decomposition feedstock (≤5.0 ppm by weight for metals, much more preferably ≤1 ppm by weight; ≤100 ppb by weight for Fe); - Finally, they contain sulfur (<2 ppm by weight for the PI-150°C fraction and <2 ppm by weight for the 150°C+ fraction) and nitrogen (<5 ppm by weight for the PI-150°C fraction and <10 ppm by weight for the 150°C+ fraction), and the content is much lower than the limits required for steam decomposition feedstock (≤500 ppm by weight for S and N, preferably ≤200 ppm by weight).

[0263] The resulting liquid fractions at PI-150°C and 150°C+ are then, advantageously, sent to a steam decomposition step h). [Brief explanation of the drawing]

[0264] [Figure 1] This represents a scheme of a specific embodiment of the method of the present invention.

Claims

1. A method for processing a feedstock containing solid recovered fuel and / or pyrolysis oil from plastics, comprising: a) A selective hydrogenation step, depending on the circumstances; carried out in the presence of at least one selective hydrogenation catalyst in a reaction section that supplies the feed material and a hydrogen-containing gas stream, the temperature being 100 to 280°C, the partial pressure of hydrogen being 1.0 to 20.0 absolute MPa, and the space velocity being 0.3 to 10.0 h⁻¹. －１ This yields hydrogenated effluent; b) Hydrogenation conversion step; carried out in a hydrogenation conversion reaction section, using at least one boiling bed reactor, a jet bed reactor, or a moving bed reactor, the reactor containing at least one hydrogenation conversion catalyst, and at least the feed material or the hydrogenated effluent obtained at the end of step a) and a hydrogen-containing gas stream being supplied to the hydrogenation conversion reaction section, the operating temperature of the hydrogenation conversion reaction section being 250 to 450°C, the partial pressure of hydrogen being 1.0 to 20.0 absolute MPa, and the space velocity per hour being 0.05 to 10.0 h －１ This yields hydrogenated effluent; c) Separation step: The hydrogenated effluent obtained from step b) and an aqueous solution are fed together, and the temperature during this step is 50 to 450°C, and at least one type of gaseous effluent, aqueous effluent, and hydrocarbon effluent are obtained; d) A step of fractionating all or part of the hydrocarbon effluent obtained from step c) to obtain at least one gas stream, a hydrocarbon fraction containing a compound with a boiling point of 385°C or less, and a hydrocarbon fraction containing a compound with a boiling point greater than 385°C; e) Hydrogenation process; carried out in a hydrogenation reaction section, using at least one fixed-bed reactor, the fixed-bed reactor containing n catalyst beds, where n is an integer of 1 or more, each containing at least one hydrogenation catalyst, and at least a portion of the hydrocarbon fraction obtained from step d) containing a compound with a boiling point of 385°C or less, and a gas stream containing hydrogen being supplied to the hydrogenation reaction section, the temperature when operating the hydrogenation reaction section is 250 to 430°C, the partial pressure of hydrogen is 1.0 to 20.0 absolute MPa, and the space velocity per hour is 0.1 to 10.0 h －１ This yields hydrogenated effluent; f) Separation step: The hydrogenated effluent obtained from step e) and the aqueous solution are fed together to obtain at least gaseous effluent and hydrogenated liquid hydrocarbon effluent.

2. The method according to claim 1, comprising the selective hydrogenation step a).

3. The method according to claim 1 or 2, wherein the hydrocarbon fraction obtained from step d) containing a compound with a boiling point greater than 385°C is recycled at least partially to step b).

4. The method according to any one of claims 1 to 3, comprising a step a0) of pre-treating the raw material, performing step a0) upstream of any selective hydrogenation step a) or upstream of a hydrogenation conversion step b), and comprising a filtration step and / or a washing step with water and / or an adsorption step.

5. The method according to any one of claims 1 to 4, wherein the hydrogenated liquid hydrocarbon effluent obtained from step f) is sent to a steam decomposition step h), and the steam decomposition step h) is carried out in at least one pyrolysis furnace, the temperature at which the steam decomposition step h) is carried out is 700 to 900°C, and the pressure at which the steam decomposition step h) is carried out is 0.05 to 0.3 relative MPa.

6. The method according to any one of claims 1 to 5, further comprising a recycling step g), wherein in the step a portion of the hydrogenated liquid hydrocarbon effluent obtained from the separation step f) is sent to an optional selective hydrogenation step a) and / or a hydrogenation conversion step b) and / or a hydrogenation treatment step e).

7. The method according to any one of claims 1 to 6, wherein the separation step f) includes fractionation, which makes it possible to obtain, in addition to the gas flow, a naphtha fraction containing a compound with a boiling point of 175°C or less, and a diesel fraction containing a compound with a boiling point greater than 175°C and less than 385°C.

8. The process also includes a hydrocracking step e'), which is carried out in a hydrocracking reaction section, the hydrocracking reaction section using at least one fixed bed containing n catalyst beds, where n is an integer of 1 or more, each containing at least one type of hydrocracking catalyst, and at least a diesel fraction containing the hydrotreated effluent obtained from step e) and / or a compound obtained from step f) having a boiling point greater than 175°C and less than 385°C, and a gas stream containing hydrogen are fed to the hydrocracking reaction section, the temperature when operating the hydrocracking reaction section is 250 to 450°C, the partial pressure of hydrogen is 1.5 to 20.0 absolute MPa, and the space velocity per hour is 0.1 to 10.0 h －１ The method according to claim 7, wherein hydrocracking-treated effluent is obtained and the effluent is sent to separation step f).

9. The method according to any one of claims 1 to 8, wherein the separation step f) also includes fractionation of a naphtha fraction containing a compound with a boiling point of 175°C or less into a light naphtha fraction containing a compound with a boiling point of less than 80°C and a heavy naphtha fraction containing a compound with a boiling point of 80 to 175°C.

10. The method according to claim 9, wherein at least a portion of the heavy naphtha fraction is sent to an aromatics complex, the aromatics complex includes at least one naphtha reforming step and / or at least a portion of the light naphtha fraction is sent to a steam cracking step h).

11. The method according to any one of claims 1 to 10, wherein the selective hydrogenation catalyst in step a) comprises a support selected from alumina, silica, silica-alumina, magnesia, clay, and mixtures thereof, and at least one group VIII element and at least one group VIB element, or at least one group VIII element.

12. The method according to any one of claims 1 to 11, wherein, when step b) is performed in a boiling bed or a moving bed, the hydrogenation-conversion catalyst in step b) includes a supported catalyst comprising a group VIII metal selected from the group formed by Ni, Pd, Pt, Co, Rh and / or Ru, and optionally a group VIB metal selected from the group formed by Mo and / or W, on an amorphous mineral support selected from the group formed by alumina, silica, silica-alumina, magnesia, clay and a mixture of at least two of these minerals, and when step b) is performed in a jet bed, the hydrogenation-conversion catalyst in step b) includes a dispersed catalyst containing at least one element selected from the group formed by Mo, Fe, Ni, W, Co, V and Ru.

13. The method according to any one of claims 1 to 12, wherein the hydrogenation catalyst in step e) comprises a support selected from the group consisting of alumina, silica, silica-alumina, magnesia, clay, and mixtures thereof, and at least one group VIII element and / or at least one group VIB element.

14. The method according to claim 8, wherein the hydrocracking catalyst in step e') comprises a support selected from a combination of alumina halides, boron and aluminum oxides, amorphous silica-alumina and zeolite, and at least one group VIB metal selected individually or as a mixture from chromium, molybdenum and tungsten and / or at least one group VIII metal selected from iron, cobalt, nickel, ruthenium, rhodium, palladium and platinum.

15. The raw material supplied has the following characteristics, according to any one of claims 1 to 14: - The aromatic compound content is 0-90% by weight. - The content of halogenated compounds is 2 to 5000 ppm by weight. - The metallic element content is 10 to 10,000 ppm by weight. - Contains iron element at a concentration of 0 to 100 ppm by weight. - The silicon content is 0 to 1000 ppm by weight.

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