Process for treating pyrolysis oil for recycling in catalytic cracking unit or hydrofining unit

Abstract

Process for the treatment of feedstocks comprising plastics and / or tyres and / or solid recovered fuel pyrolysis oils containing halogenated compounds, comprising: a) a hydrotreating step to obtain a partially hydrotreated effluent having a reduced content of halogenated compounds, b) a separation step to obtain a partially hydrotreated effluent having a reduced content of halogenated compounds, and c) a separation step to obtain a partially hydrotreated effluent having a reduced content of halogenated compounds. The present invention relates to a method for hydrocracking petroleum feedstock, to which a portion of the hydrotreated effluent from step a) and an aqueous solution are fed to obtain a gaseous effluent, an aqueous effluent and a portion of the hydrotreated hydrocarbon effluent, c) a fluidized catalytic cracking or hydrofining step of a petroleum feedstock and / or a feedstock obtained from biomass conversion, wherein the partially hydrotreated hydrocarbon effluent is introduced as a co-feed without previously undergoing a further hydrotreating step performed at a higher temperature and / or pressure, the mixture of the petroleum feedstock and / or biomass feedstock and the partially hydrotreated hydrocarbon effluent having a halogen compound content of less than or equal to 10 ppm by weight.

Description

Technical Field

[0001] The present invention relates to a method for treating plastic and / or tire and / or solid recovered fuel (SRF) pyrolysis oil to obtain partially hydrotreated pyrolysis oil that can be upgraded as co-feedstock with petroleum feedstock and / or feedstock obtained from biomass conversion in refinery units such as fluid catalytic cracking units or hydrofinishing units using hydrogen, such as hydrotreating, hydrocracking or hydroconversion units. More particularly, the present invention relates to a method for treating pyrolysis oil to remove its halogenated compounds so that this oil can be easily upgraded in existing units of a refinery. Prior art

[0002] Plastic waste is typically a mixture of several polymers, such as polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, and polystyrene. Depending on their intended use, plastics may also contain other compounds besides the polymers, such as plasticizers, pigments, dyes, or polymerization catalyst residues. Plastic waste may also contain small amounts of biomass, for example, from household waste. Waste handling, particularly storage, mechanical processing, sorting, and pyrolysis, as well as the storage and transportation of pyrolysis oil, can also cause corrosion.

[0003] As for tires, they are mainly composed of rubber (a mixture of cross-linked synthetic and natural rubber type elastomers, with the addition of auxiliary agents of the silica, resin, sulfur, zinc oxide, carbon black, etc.) that provides elastic properties and fabrics and metal fibers that provide reinforcement properties.

[0004] Solid recovered fuel (SRF), also known as refuse-derived fuel (RDF), is solid non-hazardous waste prepared for energy upgrading, whether it comes from household and similar waste, waste from economic activities or construction and demolition waste. SRF is usually a mixture of any combustible waste, such as old tires, food by-products (fats, animal bone meal, etc.), viscose and wood waste, light fractions from shredders (e.g. from old vehicles, electrical and electronic equipment (WEEE)), household and commercial waste, residues from the recycling of various types of waste, including in particular certain municipal waste, plastic waste, textiles or wood. SRF often contains plastic waste.

[0005] Plastics or recycled tires or SRF from collection and sorting channels can be subjected to a pyrolysis step to obtain, in particular, pyrolysis oils. These oils generally contain a number of impurities, in particular halogenated compounds, in particular chlorine-based compounds, as well as diolefins, olefins, metals, in particular iron, silicon, or foreign elements such as sulfur, oxygen and nitrogen, and insoluble materials.

[0006] These plastics and / or tires and / or SRF pyrolysis oils are typically incinerated to generate electricity and / or used as fuel in industrial boilers or district heating boilers.

[0007] Another way to upgrade pyrolysis oil is to use these pyrolysis oils as feedstock for steam cracking units to (re)produce olefins, which are the constituent monomers of certain polymers. However, plastic and / or tire pyrolysis oils typically have a high content of impurities and are thus incompatible with steam cracking units or units located downstream of the steam cracking unit, particularly polymerization processes and selective hydrogenation processes.

[0008] One way to remove these impurities contained in pyrolysis oil is to carry out hydrotreating in the presence of a catalyst. Steam cracking units require very high feedstock purity, especially low contents of chlorine, dienes, olefins, metals and sulfur. Hydrotreating upstream of steam cracking is typically carried out in several steps and under rather stringent conditions, particularly with respect to temperature and pressure, to achieve the required specifications. Such methods are described, for example, in WO2016 / 142808, WO2016 / 142809, WO2018 / 055555, WO2021 / 110395 or WO2021 / 165178.

[0009] Another way to upgrade plastic and / or tire pyrolysis oils is to use these pyrolysis oils as feedstock in a fluid catalytic cracking (FCC) unit to mainly produce gasoline. Such methods are described, for example, in US10442997, WO2021 / 133893, WO2021 / 133889, WO2021 / 133895 and WO2021 / 201932.

[0010] Although the requirements for FCC feedstock in terms of specifications are different and generally lower in terms of purity, the hydrotreating carried out upstream to remove impurities as described in the prior art is also typically carried out under rather stringent conditions. The document WO2021 / 201932 describes, for example, an FCC pretreatment carried out by hydrotreating at a temperature between 349 - 415 °C (660 - 780 °F) and a pressure between 6.8 and 13.8 MPa (68 - 138 bar, 1000 - 2000 psi).

[0011] The present invention provides a method for mild hydrotreating of plastic and / or tire and / or SRF pyrolysis oils, in particular to enable reduction of their halogenated compounds, especially chlorine content, to obtain pyrolysis oils with most of the halogenated compounds removed, which can then be sent as a co-feed with petroleum feedstock and / or feedstock obtained from biomass conversion to refinery units such as FCC units or hydrotreating units using hydrogen such as hydrocracking, hydrotreating or hydroconversion units.

[0012] Chlorine is generally a limiting contaminant in the treatment of pyrolysis oil in existing units of refineries. Indeed, chlorine is the cause (in the form of HCI) of corrosion occurring in existing units (the metallurgy of which is generally not designed to withstand chlorine contents greater than 10 wt ppm, or even 5 wt ppm in the feedstock), even at low contents (<10 wt ppm, or even <5 wt ppm).

[0013] Different from the hydrotreating methods described in the prior art, the method according to the present invention involves mild hydrotreating, particularly at low pressure and moderate temperature. The mild operating conditions in hydrotreating, combined with a separation step with washing, make it possible to largely remove halogenated compounds while retaining as much as possible the dienes and olefins that can be upgraded (for the production of propylene) in, for example, FCC.

[0014] The method according to the present invention focuses mainly on removing halogenated compounds to make pyrolysis oil suitable as a feedstock in downstream units. The method according to the present invention does not necessarily involve complete hydrotreating of the oil. Other impurities (metals, silicon, nitrogen, etc.) contained in the pyrolysis oil are not necessarily completely removed during the process of the method according to the present invention, although the operating conditions make it possible to remove at least a part of them. These impurities may be transformed or removed in downstream units, and the residual content of the impurities is compatible with these units.

[0015] The "mild" hydrotreating of the present invention is a hydrotreating carried out under carefully selected pressure, temperature and space velocity conditions that are generally milder compared to the conventional hydrotreating known in the prior art that aims to remove all impurities. The hydrotreating of the present invention particularly makes it possible to largely remove halogenated compounds while retaining as much as possible dienes and olefins.

[0016] The object of the present invention is therefore to provide a method for treating plastic and / or tyre pyrolysis oil that is inexpensive, easy to carry out and can be easily integrated into existing refinery units. The fact of using mild operating conditions makes it possible to minimize hydrogen consumption, thereby minimizing the cost of this purification as well as the operating and investment costs, while removing as much chlorine content as possible.

[0017] Furthermore, the method according to the present invention can be carried out in a unit dedicated to pyrolysis oil and thus in a low-capacity unit so as to be able to obtain partially hydrotreated pyrolysis oil with a halogenated compound content low enough to be directly sent to existing refinery units for co-processing. There is no need to modify the existing units.

[0018] The unit of the method according to the present invention can be easily integrated into the refining unit, and due to the low pressure required, the hydrogen supply unit already existing in the refinery can also be used. Summary of the Invention

[0020] More specifically, the present invention relates to a method for treating a pyrolysis feedstock comprising plastics and / or tires and / or solid recovered fuel pyrolysis oil containing halogenated compounds, the method comprising:

[0021] a) A hydrotreating step carried out in a hydrotreating reaction section comprising at least one hydrotreating catalyst, feeding at least the pyrolysis feedstock and a gas stream containing hydrogen to the hydrotreating reaction section, the hydrotreating reaction section being used at an average temperature between 100 °C and 220 °C, a hydrogen partial pressure between 1.0 and 3.0 MPa absolute pressure, and a space velocity between 0.05 and 5 h -1 between, with a hydrogen coverage between 5 and 50 Nm 3 hydrogen / m 3 pyrolysis feedstock to obtain a partially hydrotreated effluent having hydrocarbon compounds with a reduced halogen content,

[0022] b) A separation step, feeding thereto the partially hydrotreated effluent from step a) and an aqueous solution to obtain at least a gas effluent, an aqueous effluent, and a partially hydrotreated hydrocarbon effluent,

[0023] c) A fluid catalytic cracking or hydrorefining step of a petroleum feedstock and / or a feedstock obtained from biomass conversion, wherein at least a portion of the partially hydrotreated hydrocarbon effluent from step b) is introduced as a co-feed, the said portion of the partially hydrotreated hydrocarbon effluent from step b) being introduced without first undergoing another hydrotreating step carried out at a temperature and / or pressure higher than the temperature and / or pressure of step a), the mixture of the petroleum feedstock and / or the feedstock obtained from biomass conversion and the said portion of the partially hydrotreated hydrocarbon effluent from step b) having a halogen content of less than or equal to 10 weight ppm.

[0024] According to a variant, the weight ratio of the flow rate of the partially hydrotreated hydrocarbon effluent from step b) introduced in step c) to the flow rate of the petroleum feedstock and / or the feedstock obtained from biomass conversion is less than 1.

[0025] According to a variant, the pyrolysis feedstock consists of plastics and / or tires and / or solid recovered fuel pyrolysis oil.

[0026] According to a variant, the content of halogenated compounds in the pyrolysis feedstock is between 1 and 5000 weight ppm.

[0027] According to a variant, the hydrotreating catalyst of step a) comprises a support selected from alumina, silica, silica-alumina, magnesia, clay, and mixtures thereof and a hydrodehydrogenation functionality containing at least one Group VIII element and at least one Group VIB element, or at least one Group VIII element.

[0028] According to one variant, the process comprises at least one step a0) of pretreatment of the pyrolysis feedstock comprising plastics and / or tires and / or SRF pyrolysis oil, said pretreatment step being carried out upstream of step a) and comprising an adsorption step and / or a filtration step and / or a centrifugation step and / or a sedimentation step and / or an electrostatic separation step and / or a washing step with an aqueous solution and / or a gas stripping step.

[0029] According to one variant, the petroleum feedstock is chosen from gasoline, gas oil, vacuum gas oil, atmospheric residue, vacuum residue, atmospheric distillate, vacuum distillate, heavy fuel oil, oil, wax and paraffin, waste oil, deasphalted residue or crude oil, petroleum feedstocks originating from thermal or catalytic conversion processes, or mixtures of these feedstocks.

[0030] According to one variant, the feedstock derived from biomass is chosen from vegetable oils, oils from algae or algae oils, fish oils, waste cooking oils and fats of plant or animal origin; fatty acid methyl esters of plant and / or animal origin, fatty acid methyl esters from waste cooking vegetable oils, feedstocks derived from thermal or catalytic biomass conversion processes, or mixtures of these feedstocks.

[0031] According to an alternative form, the reaction stage of step a) uses at least two reactors operated in displaceable mode.

[0032] According to one variant, the fluid catalytic cracking step c) is carried out in a fluid catalytic cracking reaction section in a substantially vertical reactor in upflow mode or downflow mode in the presence of a zeolite catalyst at a reactor temperature between 450° C. and 600° C. with a contact time in the reactor of less than 1 minute.

[0033] According to one variant, the hydrofinishing step c) is a hydrotreating step carried out in a hydrotreating reaction section comprising at least one hydrotreating catalyst, to which is fed at least a gas stream comprising hydrogen, the hydrotreating reaction section being subjected to an average temperature between 180° C. and 480° C., a hydrogen partial pressure between 0.5 and 25 MPa absolute, a gas pressure between 0.1 and 20 h -1 Space speed between 50 and 5000Nm 3 Hydrogen / m 3 Use under hydrogen coverage between feedstocks.

[0034] According to one variant, the hydrofinishing step c) is a hydrocracking step carried out in a hydrocracking reaction section comprising at least one hydrocracking catalyst, to which a gas stream comprising hydrogen is fed, the hydrocracking reaction section being operated at an average temperature between 250° C. and 480° C., a hydrogen partial pressure between 2 and 25 MPa absolute, a temperature between 0.5 and 40 h. -1Space speed between 80 and 5000Nm 3 Hydrogen / m 3 Use under hydrogen coverage between feedstocks.

[0035] According to one variant, the hydrofinishing step c) is a hydroconversion step carried out in a hydroconversion reaction section comprising at least one hydroconversion catalyst, to which a gas stream comprising hydrogen is fed, the hydroconversion reaction section being heated at an average temperature between 340° C. and 550° C., a hydrogen partial pressure between 2 and 38 MPa absolute, a temperature between 0.05 and 10 h. -1 Space speed between 50 and 5000Nm 3 Hydrogen / m 3 Use under hydrogen coverage between feedstocks.

[0036] In the following, unless otherwise indicated, the term "pyrolysis oil" is understood to mean oil obtained from the pyrolysis of plastics and / or tires and / or SRF.

[0037] According to the present invention, pressures are absolute pressures, also indicated as abs., and are given in MPa absolute (or MPa abs.), unless otherwise stated.

[0038] According to the present invention, the expressions "between ... and ..." and "... to ..." are equivalent and mean that the limit values of the interval are included in the stated numerical range. If this is not the case and if the limit values are not included in the stated range, the present invention will give such an explanation.

[0039] Within the meaning of the present invention, the various parameter ranges of a given step, such as pressure ranges and temperature ranges, can be used alone or in combination. For example, for the present invention, a range of preferred pressure values can be combined with a range of more preferred temperature values.

[0040] Hereinafter, specific and / or preferred embodiments of the present invention may be described, which may be implemented individually or in combination, without limitation to the combination where technically feasible.

[0041] Subsequently, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, published by CRC Press, edited by DRLide, 81st edition, 2000-2001). For example, Group VIII (or VIIIB) according to the CAS classification corresponds to the metals of columns 8, 9 and 10 according to the new IUPAC classification.

[0042] Metal content was measured by X-ray fluorescence.

[0043] Details

[0044] Pyrolysis raw materials

[0045] According to the present invention, "plastic pyrolysis oil, tire pyrolysis oil, or SRF pyrolysis oil" is an oil, advantageously liquid at ambient temperature, obtained from the pyrolysis of plastics, preferably in particular from the pyrolysis of plastic waste from collection and sorting channels, or from the pyrolysis of used tires or from the pyrolysis of SRF. It comprises, in particular, a mixture of hydrocarbon compounds, especially paraffins, olefins (monoolefins and / or diolefins), cycloalkanes, and aromatics. At least 80% by weight of these hydrocarbon compounds preferably have a boiling point below 700° C., and preferably below 550° C. In particular, depending on the source of the pyrolysis oil, the pyrolysis oil may contain up to 70% by weight of paraffins, up to 90% by weight of cycloalkanes, up to 90% by weight of olefins, and up to 90% by weight of aromatics, it being understood that the sum of paraffins, cycloalkanes, olefins, and aromatics equals 100% by weight of the hydrocarbon compounds.

[0046] Pyrolysis oil may contain diolefins. Diolefin content is often indirectly measured as the maleic anhydride value (MAV). This method is based on the Diels-Alder addition reaction between conjugated diolefins and maleic anhydride. The MAV determination method is described in C. López-García et al., Near Infrared Monitoring of Low Conjugated Diolefins Content in Hydrotreated FCC Gasoline Streams, Oil & Gas Science and Technology – Rev. IFP, Vol. 62 (2007), No. 1, pp. 57-68. MAV is expressed as milligrams of maleic anhydride reacted with 1 gram of sample (mg / g). MAV varies between 5 and 100 mg / g in pyrolysis oil.

[0047] The density of pyrolysis oil measured at 15°C according to ASTM D4052 is generally around 0.75 g / cm 3 to 0.99g / cm 3 between, preferably between 0.75g / cm 3 to 0.95g / cm 3 between.

[0048] Pyrolysis oil may also comprise, and usually does comprise, impurities such as metals, especially iron, silicon or halogenated compounds, especially chlorinated compounds. These impurities may be present in the pyrolysis oil with high levels, for example 500 ppm by weight or 700 ppm by weight or 1000 ppm by weight and even 5000 ppm by weight of the halogen elements (particularly chlorine, also bromine, fluorine, iodine or astatine) provided by the halogenated compounds at the most, and usually 1 to 1000 ppm by weight or between 1 to 700 ppm by weight or between 1 to 500 ppm weight of the halogen elements. Pyrolysis oil may contain 500 ppm by weight or 700 ppm by weight or 1000 ppm by weight and even 5000 ppm by weight of the chlorine elements provided by the chlorinated compounds, and usually 1 to 1000 ppm by weight or between 1 to 700 ppm by weight or between 1 to 500 ppm by weight.

[0049] The oil can comprise 200 ppm by weight or 1500 ppm by weight of metal or semimetallic element at the most, and usually between 1 to 200 ppm by weight or between 1 to 1500 ppm by weight of metal or semimetallic element.Alkali metal, alkaline earth metal, transition metal, post-transition metal and metalloid can be classified into the same category as the pollutant of metallic property, is called metal or metal or semimetallic element.Especially, metal or metal or semimetallic element comprises silicon, iron or these two elements.Pyrolysis oil can comprise 200 ppm by weight or 1000 ppm by weight of silicon at the most especially, and usually between 1 to 200 ppm by weight or between 1 to 1000 ppm by weight or between 1 to 500 ppm by weight of silicon.Pyrolysis oil can comprise 50 ppm by weight or 100 ppm by weight of iron at the most especially, and usually between 1 to 50 ppm by weight or between 1 to 100 ppm by weight of iron.Pyrolysis oil can also comprise phosphorus, sodium, calcium, potassium and magnesium.

[0050] The pyrolysis oil may also contain other impurities, such as foreign elements provided in particular by sulphur compounds, oxygen compounds and / or nitrogen compounds, the content being generally less than 40,000 ppm by weight of foreign elements, preferably less than 15,500 ppm by weight of foreign elements and generally between 1 and 40,000 ppm by weight or between 1 and 15,500 ppm by weight of foreign elements.

[0051] The sulfur compounds are generally present in a content of less than 15,000 ppm by weight, preferably less than 10,000 ppm by weight, and generally between 1 and 15,000 ppm by weight or between 1 and 10,000 ppm by weight of sulfur compounds.

[0052] The content of oxygen compounds is usually present in an amount of less than 15,000 weight ppm, preferably less than 10,000 weight ppm, and usually between 1 and 15,000 weight ppm or between 1 and 10,000 weight ppm.

[0053] The content of nitrogen compounds is usually present in an amount of less than 10,000 weight ppm, preferably less than 5,000 weight ppm, and usually between 1 and 10,000 weight ppm or between 1 and 5,000 weight ppm.

[0054] The content of sulfur, oxygen and / or nitrogen compounds usually depends on the source of the oil. Therefore, tire pyrolysis oil usually contains more heteroelements, especially sulfur compounds, than plastic pyrolysis oil.

[0055] The pyrolysis oil may also contain other impurities such as heavy metals, such as mercury, arsenic, zinc and lead, for example up to 100 weight ppb or 200 weight ppb of mercury or arsenic, and usually between 1 and 200 weight ppb or between 1 and 100 weight ppb of heavy metals.

[0056] The pyrolysis feedstock for the process according to the invention comprises at least one plastic and / or tire and / or SRF pyrolysis oil. The feedstock may consist only of pyrolysis oil. Preferably, relative to the total weight of the feedstock, the feedstock comprises at least 50% by weight, preferably between 70% and 100% by weight, of pyrolysis oil, i.e. preferably between 50% and 100% by weight, and preferably between 70% and 100% by weight of plastic pyrolysis oil.

[0057] Particularly preferably, the pyrolysis feedstock for the process according to the invention consists only of plastic and / or tire and / or SRF pyrolysis oil.

[0058] In the case of a mixture of plastic pyrolysis oil, tire pyrolysis oil and / or SRF pyrolysis oil, such a mixture can be produced in any proportion.

[0059] According to another variant, the pyrolysis feedstock for the process according to the invention introduced in step a) may, in addition to pyrolysis oil, also contain a conventional petroleum feedstock or a feedstock obtained from biomass conversion, which is subsequently co-processed with the pyrolysis oil of the feedstock.

[0060] The conventional petroleum feedstock introduced in step a) may advantageously be a fraction or a mixture of fractions of the naphtha or gas oil type.

[0061] In step a), the raw material available from biomass conversion introduced can advantageously be selected from vegetables oil, from the oil or algae oil of algae, fish oil, waste edible oil and plant or the mixture of fat or these raw materials of animal origin. Said vegetables oil can advantageously be wholly or partly rough or refined, and derive from the plant that is selected from rapeseed, sunflower, soybean, palm, olive, coconut, coconut kernel, castor oil plant, cotton plant, peanut oil, linseed oil and sea kale oil, and for example all oils that are obtained by genetic modification or hybridization by sunflower or rapeseed, this list is not restrictive. Said animal fat is advantageously selected from blubber and the fat that is made up of the residue of food industry or from the fat of catering industry. Also can use frying oil, various animal oils, as fish oil, tallow or lard. The raw material available from biomass conversion also can advantageously be selected from the fatty acid methyl ester of plant and / or animal origin or from the fatty acid methyl ester of waste edible vegetable oil.

[0062] The raw materials obtained from biomass conversion can also be selected from the raw materials deriving from heat or catalytic biomass conversion process, as by biomass, particularly by various liquefaction methods, as the oil produced by hydrothermal liquefaction or pyrolysis by lignocellulosic biomass.Term " biomass " refers to the material derived from the most recently living organism (recently living organisms), and it includes plants, animals and their by-products.Term " lignocellulosic biomass " refers to the biomass derived from plant or its by-product.Lignocellulosic biomass is made up of carbohydrate polymers (cellulose, hemicellulose) and aromatic polymers (lignin).

[0063] The raw materials obtained from biomass conversion can also advantageously be selected from raw materials from the paper industry.

[0064] Plastic and / or tire and / or SRF pyrolysis oils may result from a thermal or catalytic pyrolysis process, or be prepared by hydropyrolysis (pyrolysis in the presence of a catalyst and hydrogen).

[0065] Pretreatment (optional)

[0066] Said feedstock comprising plastics and / or tyres and / or SRF pyrolysis oil may advantageously be pretreated in at least one optional pretreatment stage a0) prior to the hydrotreatment step a) to obtain a pretreated feedstock to feed step a).

[0067] According to one variant, this optional pretreatment step a0) can reduce the amount of contaminants and solid particles that may be present in the feedstock containing pyrolysis oil, especially the amount of iron and / or silicon and / or chlorine. This optional step a0) can especially remove deposits that may form due to the unstable nature of pyrolysis oil and / or compatibility problems between two different feedstocks. Therefore, especially when the feedstock contains more than 10 weight ppm, especially more than 20 weight ppm, more especially more than 50 weight ppm of metal elements and / or solid particles, and especially when the feedstock contains more than 5 weight ppm of silicon, more especially more than 10 weight ppm, even more than 20 weight ppm of silicon, the optional pretreatment step a0) of the feedstock containing pyrolysis oil is advantageously carried out. Similarly, especially when the feedstock contains more than 10 weight ppm, especially more than 20 weight ppm, more especially more than 50 weight ppm of chlorine, the optional pretreatment step a0) of the feedstock containing pyrolysis oil is advantageously carried out.

[0068] The optional pretreatment step a0) can be carried out by any method known to those skilled in the art that can reduce the amount of contaminants. It can especially include an adsorption step and / or a filtration step and / or a centrifugation step and / or a sedimentation step and / or an electrostatic separation step and / or a step of washing with an aqueous solution and / or a gas stripping step.

[0069] This optional pretreatment step a0) is advantageously carried out at a temperature between 20 and 400 °C, preferably between 40 and 350 °C, and at a pressure between 0.15 and 10.0 MPa absolute pressure, preferably between 0.2 and 7.0 MPa absolute pressure.

[0070] According to one variant, the optional pretreatment step a0) is carried out in an adsorption section that operates in the presence of at least one adsorbent. The adsorbent can be selected from zeolites, activated carbon, clays, silica, or alumina. Preferably, the adsorbent is alumina with a specific surface area greater than or equal to 100 m 2 / g, preferably greater than or equal to 200 m 2 / g. The specific surface area of the at least one adsorbent is advantageously less than or equal to 600 m 2 / g, especially less than or equal to 400 m 2 / g. The specific surface area of the adsorbent is the surface area measured by the BET method, that is, the specific surface area measured by nitrogen adsorption according to the standard ASTM D 3663-78 established by the Brunauer-Emmett-Teller method described in the journal The Journal of the American Chemical Society, 6Q, 309 (1938).

[0071] Advantageously, the adsorbent contains less than 1% by weight of metal elements and is preferably free of metal elements. The metal elements of the adsorbent should be understood as meaning elements from Groups 6 to 10 of the Periodic Table of the Elements (new IUPAC classification). The residence time of the feedstock in the adsorption zone is generally between 1 and 180 minutes.

[0072] The adsorption stage of optional step a0) comprises at least one adsorption tower, preferably at least two adsorption towers, preferably 2 to 4 adsorption towers, containing the adsorbent. When the adsorption stage comprises two adsorption towers, one operating mode can be "swing" operation, in which one tower is online, i.e., in operation, while the other tower is on standby. When the adsorbent in the online tower is exhausted, that tower is isolated while the standby tower is online, i.e., in operation. The exhausted adsorbent can then be regenerated in situ and / or replaced with fresh adsorbent so that the tower containing it can be put back online once the other tower is isolated.

[0073] Another mode of operation is to have at least two towers run in series. When the adsorbent of the tower placed at the top is exhausted, the first tower is isolated and the exhausted adsorbent is regenerated in situ or replaced with new adsorbent. The tower is then returned to the last position on the line, and so on. This operation is called permutable mode, or PRS, that is, a permutable reactor system (Permutable Reactor System), or "lead and lag". The combination of at least two adsorption towers makes it possible to overcome the possible and potentially rapid poisoning and / or clogging of the adsorbent caused by the combined effects of metal contaminants, dienes, sludge obtained from dienes and insolubles that may be present in the pyrolysis oil to be treated. This is because the presence of at least two adsorption towers promotes the replacement and / or regeneration of the adsorbent, advantageously without shutting down the pretreatment unit or even the process, thereby reducing the risk of clogging and thus avoiding shutting down the unit due to clogging, controlling costs and limiting the consumption of adsorbent.

[0074] According to another variant, the optional pretreatment step a0) is carried out in a washing stage using an aqueous solution, for example water or an acidic or alkaline solution. This washing stage may comprise equipment components capable of contacting the feedstock with the aqueous solution and separating the phases, in order to obtain, on the one hand, a pretreated feedstock and, on the other hand, an aqueous solution containing impurities. These equipment components may include, for example, stirred reactors, settlers, mixer-settlers, and / or co-current or counter-current washing columns.

[0075] According to another variant, the optional pretreatment step a0) is carried out by filtration. The filtration step enables the removal of inorganic solids, deposits and / or fines contained in the feedstock, in particular metals, metal oxides and metal chlorides. Filters with a pore size (e.g., diameter or equivalent diameter) less than 25 μm, preferably less than or equal to 10 μm, and even more preferably less than or equal to 5 μm are generally used. According to another variant, filters with a pore size less than 25 μm but greater than 5 μm can be used. A series of filters with different pore sizes can also be used, especially a series of filters with decreasing pore sizes in the direction of feedstock flow. These filter media are well known for industrial use. Cartridge filters or self-cleaning filters are suitable, for example. The solids content can be measured, for example, by the heptane insolubles test, ASTM D-3279 method. The content of heptane insolubles must be reduced to less than 0.5 wt%, preferably reduced to less than 0.1%.

[0076] According to a specific embodiment, the pretreatment step a0) carried out by filtration comprises at least one filter with a pore size less than 10 μm and preferably greater than 5 μm, optionally followed by a filtration system with a pore size less than 2 μm and preferably less than 1 μm.

[0077] According to another specific embodiment, the pretreatment step a0) carried out by filtration comprises at least one filter with a pore size less than 10 μm and preferably greater than 5 μm, followed by an electrostatic precipitation system.

[0078] According to another specific embodiment, the pretreatment step a0) carried out by filtration comprises at least one filter with a pore size less than 10 μm and preferably greater than 5 μm, followed by a filter system using a filter aid such as sand or diatomaceous earth.

[0079] According to another variant, the optional pretreatment step a0) is carried out by centrifugation. According to another variant, the pretreatment step a0) includes centrifugation and filtration.

[0080] According to another variant, the optional pretreatment step a0) is carried out by sedimentation. According to another variant, the pretreatment step a0) includes sedimentation and filtration.

[0081] According to another variant, the optional pretreatment step a0) is carried out by gas stripping, thereby reducing the oxygen content in the feedstock. Gas extraction can remove the oxygen (O2) that may be dissolved in the feedstock, thereby reducing the possibility of forming free radicals that cause polymerization in downstream steps. This method generally involves contacting the feedstock with an extraction gas (such as H2, N2 or a mixture thereof), thereby transferring at least a portion of the dissolved oxygen in the feedstock to the extraction gas, and then separating the extraction gas from the feedstock. The volume of the extraction gas relative to the volume of the feedstock (the two volumes measured under gas extraction conditions) is generally greater than 1, and preferably at least 3. In a specific embodiment, the extraction gas may contain at least 60% (mole percentage) of H2. Any dissolved H2 remaining in the feedstock after the gas extraction step is not a problem due to downstream hydrotreating. Preferably, the gas extraction step is completed before any (pre)heating of the feedstock to minimize potential fouling.

[0082] The optional pretreatment step a0) generally includes one or more, preferably several, of the above treatments. It may particularly include the following series: a step of washing with an aqueous solution and / or an adsorption step, followed by a gas stripping step, followed by a filtration step and / or a subsequent centrifugation step. All these steps are preferably carried out before any (pre)heating of the feedstock.

[0083] The optional pretreatment step a0) thus enables the obtained pretreated feedstock to be subsequently fed to the hydrotreating step a).

[0084] Hydrotreating step a)

[0085] According to the present invention, the method includes step a) carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst, feeding at least a pyrolysis feedstock and a gas stream containing hydrogen to the hydrotreating reaction section, the hydrotreating reaction section being used at an average temperature between 100 °C and 220 °C, a hydrogen partial pressure between 1.0 and 3.0 MPa absolute pressure, and a space velocity between 0.05 and 5 h -1 between, with a hydrogen coverage of 5 to 50 Nm 3 hydrogen / m 3 pyrolysis feedstock, to obtain a partially hydrotreated effluent having hydrocarbon compounds with a reduced halogen content.

[0086] Step a) is particularly carried out under mild hydrogen pressure and temperature conditions, particularly enabling the removal of halogens, especially chlorine, to make the pyrolysis oil suitable as a co-feed in downstream units, while retaining as much as possible the diolefins and olefins that can be upgraded (for the production of propylene) in FCC.

[0087] Other impurities contained in the pyrolysis oil (metals, silicon, nitrogen, etc.) are not necessarily completely removed during the process of the method according to the invention, although the operating conditions make it possible to remove at least a part thereof. Step a) thus mainly relates to the hydrogenation reaction of halogenated compounds and, to a lesser extent, also to other hydrotreating reactions known to those skilled in the art, in particular hydrotreating reactions such as aromatic hydrogenation, hydrodesulfurization and hydrodenitrogenation, as well as the hydrogenation of olefins and diolefins (although attempts are made to retain them in the oil).

[0088] The hydrotreating reaction section is advantageously used at an average hydrotreating temperature (or WABT as defined below) between 100 °C and 220 °C, preferably between 120 and 200 °C, at an absolute pressure between 1.0 and 3.0 MPa, preferably between 1.0 and 2.4 MPa, preferably between 1.2 and 2.2 MPa, and at a space velocity (HSV) between 0.1 and 5 h -1 between, preferably between 0.1 and 2 h -1 between, preferably between 0.1 and 1.0 h -1 between. The hydrogen coverage in step a) is advantageously between 50 and 50 Nm 3 hydrogen / m 3 fresh feedstock, and preferably between 10 and 40 Nm 3 hydrogen / m 3 fresh feedstock, and preferably between 15 and 30 Nm 3 hydrogen / m 3 fresh feedstock.

[0089] According to the invention, the "average temperature" of the reaction section corresponds to the weight average bed temperature (WABT) known to those skilled in the art. The average temperature is advantageously determined according to the catalytic system used, the equipment parts, and the configuration thereof. The average temperature (or WABT) is calculated in the following manner:

[0090] WABT = ( T inlet + T outle t ) / 2

[0091] where T inlet : the temperature of the stream at the inlet of the reaction section, and T outlet : the temperature of the effluent at the outlet of the reaction section. Unless otherwise stated, the "average temperature" of the reaction section is given under the start-up conditions of the cycle.

[0092] The space velocity (HSV) is defined herein as the ratio of the hourly volume flow rate of the feedstock containing pyrolysis oil, which has been optionally pre-treated, to the volume of the catalyst.

[0093] The hydrogen coverage is defined as the ratio of the hydrogen gas flow rate obtained under standard temperature and pressure conditions to the volume flow rate of the "fresh" feedstock (i.e., the feedstock to be treated that has been optionally pre-treated, disregarding the recycle part) at 15 °C (expressed as Nm 3 (denoted as Nm 3 ) of H2 / m 3 of feedstock).

[0094] The gas stream containing hydrogen in the feed hydrotreating reaction section can consist of hydrogen supply and / or recycled hydrogen. Preferably, advantageously, an additional gas stream containing hydrogen is introduced at the inlet of each reactor (especially when operating in series) and / or at the inlet of each catalyst bed starting from the second catalyst bed of the reaction section. These additional gas streams are also referred to as cooling streams. They enable the control of the temperature in the reactor, where the reactions occurring in the reactor are usually highly exothermic.

[0095] The gas stream containing hydrogen can be derived from a fossil source or a renewable source, for example, derived from the gasification of plastic waste or produced by electrolysis.

[0096] Advantageously, the gas stream containing hydrogen is derived from a compressor used in a refinery, which is used to feed another hydrotreating unit using hydrogen, such as a hydrocracking, hydrotreating, or hydroconversion unit. The gas stream containing hydrogen can, for example, be derived from a compressor used to feed a vacuum gas oil (VGO) hydrotreating unit. This has the advantage of not requiring a dedicated compressor to recycle the hydrogen from step b) and thus saving investment costs.

[0097] Optionally, a part of the partially hydrotreated hydrocarbon (recycle) effluent from step b) as described below can also be additionally supplied to the reaction section of step a).

[0098] Preferably, the method according to the invention includes a hydrotreating step a) carried out in a hydrotreating reaction section using at least one fixed-bed reactor having n catalyst beds, where n is an integer greater than or equal to 1, preferably between 1 and 10, more preferably between 2 and 5, and each catalyst bed contains at least one hydrotreating catalyst.

[0099] At least the optionally pre-treated pyrolysis feedstock and a gas stream containing hydrogen are fed to the hydrotreating reaction section, advantageously at the first catalyst bed of the first reactor in operation. It is also possible to inject at least a part of the pyrolysis feedstock and / or at least a part of the hydrogen between the various catalyst beds.

[0100] The hydrotreating reaction section using at least one fixed-bed reactor can operate in a gas and liquid downflow or upflow.

[0101] Advantageously, the reaction section of step a) comprises 1 to 5 reactors, preferably 2 to 5 reactors, and particularly preferably comprises two reactors. The advantage of a hydrotreatment reaction section comprising several reactors is that the treatment of the feedstock is optimized while being able to reduce the risk of catalyst bed blockage and thus avoid shutdowns of the unit due to blockages.

[0102] According to this embodiment, the hydrotreatment reaction section of step a) comprises two reactors operating in permutable mode, known as PRS, i.e., permutable reactor system, or "lead and lag." The combination of at least two reactors in PRS mode makes it possible to isolate the reactors in order to drain out the spent catalyst, refill them with fresh catalyst, and put them back into service without shutting down the process. PRS technology is described, in particular, in patent FR 2,681,871.

[0103] According to another embodiment, the hydroprocessing reaction section comprises a single fixed bed reactor containing n catalyst beds, n being an integer greater than or equal to 1, preferably between 1 and 10, more preferably between 2 and 5.

[0104] Advantageously, reactor internals, for example of the filter plate type, may be used to prevent clogging of the reactor. An example of a filter plate is described in patent FR 3051375.

[0105] Preferably, step a) can use, upstream of the hydrotreatment catalyst, at least one guard bed containing an adsorbent of the alumina, silica, silica-alumina, zeolite and / or activated carbon type, optionally containing a metal of Group VIB and / or Group VIII. It is also possible to use a series of guard beds having particles of different diameters, in particular a series of guard beds with decreasing diameter in the direction of flow of the feedstock (also called "graded").

[0106] Advantageously, the hydrotreating catalyst comprises a support, preferably an inorganic support, and a hydrogenation-dehydrogenation function.

[0107] According to one variant, the hydrogenation-dehydrogenation function comprises, in particular, at least one element from Group VIII, preferably chosen from nickel and cobalt, and at least one element from Group VIB, preferably chosen from molybdenum and tungsten. According to this variant, the total content of metal elements from Groups VIB and VIII, expressed as oxides, is preferably between 1% and 40% by weight, preferably between 5% and 30% by weight, relative to the total weight of the catalyst. When the metal is cobalt or nickel, the metal content is expressed as CoO and NiO, respectively. When the metal is molybdenum or tungsten, the metal content is expressed as MoO3 and WO3, respectively.

[0108] The weight ratio of the Group VIB metal expressed as metal oxide to the Group VIII metal is preferably between 1 and 20, and preferably between 2 and 10 in a preferred manner.

[0109] According to this variant, the reaction section of step a) comprises, for example, a hydrotreating catalyst comprising 0.5% to 12% by weight of nickel, preferably 0.9% to 10% by weight of nickel (expressed as nickel oxide NiO relative to the weight of the catalyst), and 1% to 30% by weight of molybdenum, preferably 3% to 20% by weight of molybdenum (expressed as molybdenum trioxide MoO3 relative to the weight of the catalyst) on a preferred inorganic support, preferably on an alumina support.

[0110] According to another variant, the hydrodehydrogenation functionality comprises at least one Group VIII element, preferably nickel, and is preferably composed of at least one Group VIII element, preferably nickel. According to this variant, the content of nickel oxide is preferably between 1% and 50% by weight, preferably between 10% and 30% by weight, relative to the weight of the catalyst. This type of catalyst is preferably used in its reduced form on a preferred inorganic support, preferably on an alumina support.

[0111] The support of the hydrotreating catalyst is preferably selected from alumina, silica, silica-alumina, magnesia, clay and mixtures thereof. The support may include dopant compounds, especially oxides selected from boron oxide, especially boric anhydride, zirconia, ceria, titania, phosphorous pentoxide and mixtures of these oxides. Preferably, the hydrotreating catalyst comprises an alumina support optionally doped with phosphorus and optionally doped with boron. When phosphorous pentoxide P2O5 is present, its concentration is less than 10% by weight relative to the weight of alumina, advantageously at least 0.001% by weight relative to the total weight of alumina. When boric anhydride B2O3 is present, its concentration is less than 10% by weight relative to the weight of alumina, advantageously at least 0.001% relative to the total weight of alumina. The alumina used may be, for example, γ (gamma) or η (eta) alumina.

[0112] The hydrotreating catalyst is, for example, in the form of extrudates or in the form of beads.

[0113] Very preferably, in addition to the above-mentioned hydrotreating catalyst, step a) may also use at least one hydrotreating catalyst used in step a) comprising, 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 with a low metal loading may preferably be arranged upstream or downstream of the above-mentioned hydrogenation catalyst, preferably upstream.

[0114] The preparation of the catalyst used in the hydrotreatment step a) is known and generally comprises the steps of impregnating a support with a metal of Group VIII and a metal of Group VIB (when present) and optionally phosphorus and / or boron, followed by drying and then optionally calcining. The catalyst of step a) may also be a catalyst used in its reduced form, thus involving a reduction step in its preparation.

[0115] Before being used in the step of this method, catalyst is usually imposed with sulfurization to form active species. According to the content of the sulfur compound in the initial raw material to be treated, can be in optional pre-treatment step a0) or hydrotreating step a) upstream, preferably in hydrotreating step a) upstream, inject the stream containing the sulfurizing agent, to ensure enough sulfur to form the active species (sulfurized form) of catalyst. This activation or sulfurization step is carried out by methods well known to those skilled in the art, and advantageously is carried out under sulfur-reducing atmosphere (sulfo-reductive atmosphere) in the presence of hydrogen and hydrogen sulfide. Sulfiding agent is preferably H2S gas, elemental sulfur, CS2, mercaptan, sulfide and / or polysulfide, contain the hydrocarbon fraction with a boiling point less than 400 ℃ of sulfur compounds or be used to activate hydrocarbon feed with any other sulfur-containing compound of sulfurized catalyst. The sulphur-containing compound is advantageously selected from alkyl disulfides, such as dimethyl disulfide (DMDS), alkyl sulphides, such as dimethyl sulfide, mercaptans, such as n-butyl mercaptan (or 1-butyl mercaptan), and the polysulphide compounds of tert-nonyl polysulphide types. The catalyst can also be sulphurised with the sulphur contained in the desulphurised raw material. Preferably, the catalyst is in situ sulphurised in the presence of a sulphurising agent and a hydrocarbon feedstock. Very preferably, the catalyst is in situ sulphurised in the presence of a raw material to which dimethyl disulfide has been added. The sulphurising agent can be injected continuously.

[0116] Part of the hydrotreated effluent obtained at the end of hydrogenation step a) is preferably sent directly to washing / separation step b).

[0117] Separation step b)

[0118] According to the present invention, the treatment method comprises a separation step b), advantageously carried out in at least one washing / separation section, to which is fed at least a part of the hydrotreated effluent and the aqueous solution from step a) to obtain at least a gaseous effluent, an aqueous effluent and a part of the hydrotreated hydrocarbon effluent.

[0119] This separation step b) in particular makes it possible to remove the hydrogen halide (in particular HCl), in the form of a halogen (chlorine), formed by the reaction of hydrogen ions and halogen ions released by the hydrogenation of halogenated compounds during step a) and dissolved in the aqueous solution.

[0120] The separation step b) is advantageously carried out at a temperature between 20 °C and 200 °C, preferably between 50 °C and 180 °C, more preferably between 80 °C and 150 °C. Advantageously, the separation step b) is carried out at a pressure close to the pressure used in step a), preferably between 1.0 and 2.0 MPa, to facilitate the recycling of hydrogen (if required).

[0121] This separation step can advantageously be carried out by any method known to those skilled in the art, such as a combination of one or more separators (drums) and / or one or more stripping columns, which separator(s) (drum) and / or column(s) can optionally be fed with a stripping gas, such as a hydrogen-rich gas stream. The washing / separation section of step c) can be carried out at least in part in common or separate washing and separation equipment parts.

[0122] Advantageously, the separation step b) comprises injecting an aqueous solution, preferably water, into a part of the hydrotreated effluent from step a) upstream of the washing / separation section to dissolve the hydrogen halide (in particular HCl) present and, preferably, all of any salts.

[0123] The aqueous solution can be water. It can also be an alkaline aqueous solution (for example by adding NaOH). Using an alkaline solution makes it possible to neutralize the hydrogen halide and any dissolved salts.

[0124] In an optional embodiment of the present invention, the separation step b) comprises injecting an aqueous solution into a partially hydrotreated effluent from step a), followed by a washing / separation section which advantageously comprises a separation stage to obtain at least one aqueous effluent carrying hydrogen halide (in particular HCl) and any dissolved salts present, a washed partially hydrotreated effluent and a partially washed gas effluent. The aqueous effluent and the washed partially hydrotreated effluent can then be separated in a knockout drum to obtain the washed partially hydrotreated effluent and the aqueous effluent. The partially washed gas effluent can be introduced simultaneously into a washing column where it is circulated countercurrently with an aqueous stream preferably having the same properties as the aqueous solution injected into the partially hydrotreated effluent, which makes it possible to remove at least a part, preferably all, of the hydrochloric acid contained in the partially washed gas effluent and thus to obtain the gas effluent preferably substantially comprising hydrogen and an acidic aqueous stream. The aqueous effluent obtained from the knockout drum can optionally be mixed with the acidic aqueous stream and optionally used as a mixture with the acidic aqueous stream in a water recycle loop to feed the aqueous solution and / or the aqueous stream into the washing column upstream of the washing / separation section to the separation step b). The water recycle loop can comprise a supply of water and / or a supply of basic solution and / or a bleed to enable the removal of impurities.

[0125] The hydrotreating step a) mainly relates to the hydrogenation reaction of halogenated compounds and also, to a lesser extent, to other hydrotreating reactions such as hydrodenitrogenation by hydrogenation of nitrogen compounds to produce NH3 and hydrodesulfurization by hydrogenation of sulfur compounds to produce H2S.

[0126] When NH3 is present in the partially hydrotreated effluent from step a), the separation step b) is also able to remove ammonium chloride salts formed by the reaction between chloride ions (which are released in the form of HCl from the hydrogenation of halogenated compounds especially during the process of step a)) and ammonium ions (which are formed in the form of NH3 from the hydrogenation of nitrogen compounds during the process of step a)) by dissolving them in an aqueous solution.

[0127] When H2S is present in the partially hydrotreated effluent from step a), the separation step b) is also able to remove ammonium sulfide ((NH4)2S) salts formed by the reaction between H2S from the hydrodesulfurization of sulfur compounds and NH3 by dissolving them in an aqueous solution.

[0128] According to one embodiment, and depending on the content of chlorine compounds in the initial or pretreated feedstock, a stream containing nitrogen compounds such as ammonia or amines, such as monoethanolamine, diethanolamine, and / or mono- and diethanolamine, can be injected upstream of the hydrotreating step a) to ensure that a sufficient amount of ammonium ions combine with the chloride ions formed during the hydrotreating step in the form of ammonium chloride salt, thereby making it possible to limit the formation of hydrochloric acid and thus limit the corrosion downstream of the separation section.

[0129] The gas effluent obtained at the end of step b) advantageously contains hydrogen, preferably containing at least 80% by volume, preferably at least 85% by volume of hydrogen. The gas effluent obtained at the end of step b) contains very little chlorine, usually with a content of less than 5 weight ppm of chlorine, which makes it possible to feed it into a refining unit that requires hydrogen.

[0130] According to one embodiment, the gas effluent can be at least partially recycled to the hydrotreating step a), and the recycling system may possibly include a purification section (for example, for adsorbing heavy metals such as mercury).

[0131] According to another preferred embodiment, the gas effluent can be at least partially recycled upstream of a hydrogen compressor used to feed a hydrofinishing unit that uses hydrogen in a refinery, such as a hydrocracking unit, a hydrotreating unit, or a hydroconversion unit. The gas effluent can be particularly recycled upstream of a compressor used to feed a vacuum gas oil (VGO) hydrotreating unit. This has the advantage of being able to eliminate the need for a dedicated compressor to recycle the hydrogen from step b) and thus save investment costs.

[0132] Regarding the partially hydrotreated hydrocarbon liquid effluent from step b) and according to a variant, a part of the partially hydrotreated hydrocarbon effluent from step b) can be recycled upstream of step a). Recycling a part of the partially hydrotreated hydrocarbon effluent from step b) upstream of step a) advantageously makes it possible on the one hand to dilute impurities and on the other hand to control the temperature in step a), where the reactions involved can be highly exothermic. Diluting the impurities makes it possible to limit unwanted reactions, such as the polymerization of diolefins (formation of gum) and / or the formation of coke.

[0133] Advantageously, the amount of recirculation of the portion of the hydrotreated hydrocarbon effluent from step b) is adjusted, i.e., the fraction of the resulting product that is recycled, so that the weight ratio of the recirculated stream from step b) to the feedstock containing pyrolysis oil (i.e., the feedstock to be treated that is fed to the entire process) is less than or equal to 10, preferably less than or equal to 7, and preferably greater than or equal to 0.001, preferably greater than or equal to 0.01, and preferably greater than or equal to 0.1. Preferably, the amount of recirculation of the portion of the hydrotreated hydrocarbon effluent from step b) is adjusted so that the weight ratio of the recirculated stream to the feedstock containing pyrolysis oil is between 0.01 and 10, preferably between 0.1 and 7, and particularly preferably between 0.2 and 5. This recirculation rate makes it particularly possible to control the temperature increase in step a). This is because, when the recirculation rate is high, the dilution rate of the feedstock is high, and the temperature increase at the beginning of the reaction stage in step a) can therefore be controlled by the dilution effect. The injection of the partially hydrotreated hydrocarbon effluent from step b) can be carried out at the first catalyst bed of the reaction section of step a) or between the various catalyst beds. When the hydrotreatment reaction section of step a) comprises two reactors operated in displaceable mode, at least a portion of the partially hydrotreated hydrocarbon effluent from step b) can be recycled between the two reactors.

[0134] According to another preferred embodiment, the partially hydrotreated hydrocarbon effluent from step b) is sent partly, and preferably completely, as co-feed directly to the inlet of a refinery unit such as an FCC unit or a unit using hydrogen, such as a hydrocracking, hydrotreating or hydroconversion unit. This has the advantage that no recycle compressor is required.

[0135] Said partly hydrotreated hydrocarbon effluent from step b) thus obtained by the treatment of steps a) and b) of the process according to the invention has a composition suitable for introduction as co-feed together with petroleum feedstocks and / or feedstocks derived from biomass into an FCC unit or a hydrofinishing unit.

[0136] The partially hydrotreated hydrocarbon effluent from step b) is in particular an effluent having a reduced content of halogenated compounds, in particular of chlorine.

[0137] Preferably, at least 50% and more preferably at least 75% of the halogenated compounds of the initial feedstock are removed during steps a) and b).

[0138] Preferably, at least 80%, and more preferably at least 90%, of the olefins are retained during step a).

[0139] Preferably, at least 25%, and more preferably at least 40%, of the dienes remain during step a).

[0140] Other impurities contained in the pyrolysis oil (metals, silicon, nitrogen, etc.) are not necessarily completely removed during the processes of steps a) and b) of the method according to the invention, although the operating conditions make it possible to remove at least a part thereof. Specifically, the pyrolysis oil (which is a partially hydrotreated hydrocarbon effluent) does not need to be completely hydrotreated to be introduced into a downstream FCC refining or hydrotreating unit, and in particular it does not need to undergo a further hydrotreating step carried out at a higher temperature and / or pressure before its introduction into the downstream unit. The remaining impurities may be transformed or removed in the downstream unit, and the residual content of the impurities is compatible with these units.

[0141] Preferably, at least 50%, and more preferably at least 75%, of the metal elements of the initial feedstock are removed during the processes of steps a) and b).

[0142] Generally, at most 50%, and more preferably at most 25%, of the sulfur compounds in the initial feedstock are removed during the processes of steps a) and b).

[0143] Preferably, at least 25%, and more preferably at least 50%, of the oxygenates of the initial feedstock are removed during the processes of steps a) and b).

[0144] Generally, at most 30%, and more preferably at most 15%, of the nitrogen compounds of the initial feedstock are removed during the processes of steps a) and b).

[0145] The contents of heavy metals such as mercury, arsenic, zinc and lead remain substantially unchanged.

[0146] The contents are given as relative weight concentration, weight percentage (%), parts per million by weight (ppm) or parts per billion by weight (ppb) relative to the total weight of the stream under consideration.

[0147] FCC or hydrotreating step c)

[0148] According to the invention, the method comprises a fluid catalytic cracking or hydrotreating step c) of a petroleum feedstock and / or a feedstock obtained from biomass conversion, in which at least a part of the partially hydrotreated hydrocarbon effluent from step b) is introduced as a co-feed, and the said partially hydrotreated hydrocarbon effluent from step b) is introduced without first undergoing another hydrotreating step carried out at a temperature and / or pressure higher than the temperature and / or pressure of step a), and the mixture of the said petroleum feedstock and / or the said feedstock obtained from biomass conversion and the said partially hydrotreated hydrocarbon effluent from step b) has a halogen content of less than or equal to 10 ppm by weight.

[0149] Since the hydrotreating step a) enables the release of halogenated compounds (such as chlorine) mainly in gaseous form (especially HCl-type hydrogen halides), the subsequent washing / separation step b) enables the dissolution and removal of hydrogen halides, and the partially hydrotreated hydrocarbon effluent from step b) has a sufficiently reduced halogenated compound content to be able to be injected as a co-feed into units for fluid catalytic cracking, hydrocracking, hydrotreating or hydroconversion of petroleum feedstocks and / or feedstocks obtained from biomass conversion.

[0150] In fact, chlorine is usually a limiting contaminant in the treatment of pyrolysis oil in existing units. Chlorine is the cause of corrosion (in the form of HCI) even at low contents (<10 ppm, or even <5 wt ppm) in existing units whose metallurgy is usually not designed to withstand chlorine contents greater than 10 ppm, or even 5 wt ppm, in the feedstock.

[0151] The partially hydrotreated hydrocarbon effluent from step b) is introduced into units for fluid catalytic cracking or hydrorefining of petroleum feedstocks and / or feedstocks obtained from biomass conversion in an amount such that the chlorine content in the mixture of the petroleum feedstock and / or feedstock obtained from biomass conversion and the partially hydrotreated hydrocarbon effluent from step b) is less than or equal to 10 wt ppm, preferably less than or equal to 5 wt ppm.

[0152] Generally, in the process according to the invention, the weight ratio of the flow rate of the partially hydrotreated hydrocarbon effluent (pyrolysis oil) from step b) introduced into the unit of step c) to the flow rate of the petroleum feedstock and / or feedstock obtained from biomass conversion is generally less than 1, and preferably between 0.01 and 0.9, and preferably between 0.02 and 0.5.

[0153] When the content of halogenated compounds in the partially hydrotreated hydrocarbon effluent from step b) is greater than 10 wt ppm, or even 5 wt ppm, a chlorine content of 10 ppm, or even 5 ppm, can be achieved by dilution with the petroleum feedstock and / or feedstock obtained from biomass conversion at the inlet of the unit.

[0154] During step c), the partially hydrotreated effluent from step b) is introduced as a co-feed together with the petroleum feedstock and / or feedstock obtained from biomass conversion into a fluid catalytic cracking unit or a hydrorefining unit using hydrogen, such as a hydrotreating, hydrocracking or hydroconversion unit. Preferably, the partially hydrotreated effluent from step b) is injected as a co-feed into the fluid catalytic cracking unit.

[0155] The petroleum feedstock used in a fluid catalytic cracking unit or a hydrotreating unit may be selected from gasoline, gas oil, vacuum gas oil, atmospheric residue, vacuum residue, atmospheric distillate, vacuum distillate, heavy fuel oil, oil, wax and paraffin, waste oil, deasphalted residue or crude oil, petroleum feedstocks resulting from thermal or catalytic conversion processes, or mixtures of these feedstocks.

[0156] The feedstock derived from biomass used in a fluid catalytic cracking unit or a hydrotreating unit may be selected from vegetable oils, oils from algae or algal oil, fish oil, waste cooking oil and fats of plant or animal origin; fatty acid methyl esters of plant and / or animal origin, fatty acid methyl esters from waste cooking vegetable oils, feedstocks resulting from thermal or catalytic biomass conversion processes, or mixtures of these feedstocks. It may in particular be a feedstock as described above in the pyrolysis oil feedstock section.

[0157] FCC

[0158] The fluid catalytic cracking (FCC) process is widely used in the refining industry to convert atmospheric gas oil, vacuum gas oil and atmospheric residue, lignocellulosic feedstocks or more generally feedstocks obtained from biomass, alone or as a mixture, into high-octane gasoline, light fuel oil, heavy fuel oil, light gases rich in olefins (propylene, butene) and coke. The FCC unit uses a highly active zeolite catalyst to crack heavy hydrocarbon molecules. Conventional FCC units are used. For example, a brief description of catalytic cracking (the first industrial application of which dates back to 1936 (Houdry process) or the use of fluidized bed catalysts dates back to 1942) can be found in Ullmann’s Encyclopedia of Industrial Chemistry, Volume A18, 1991, pages 61 to 64. The choice of catalyst and operating conditions depends on the desired products, which vary with the feedstock being processed, as described, for example, in the article by M. Marcilly published in revue de l'institut du pétrole [Review of the French Institute of Petroleum], November–December 1975, pages 969–1006, pages 990–991.

[0159] The fluid catalytic cracking step c) is generally carried out in a fluid catalytic cracking reaction section in a substantially vertical reactor in an upflow (riser) mode or a downflow (downcomer) mode in the presence of a feedstock selected from atmospheric gas oil, vacuum gas oil, atmospheric residue and feedstocks derived from biomass and a zeolite catalyst at a reactor temperature between 450 °C and 600 °C with a contact time in the reactor of less than 1 minute, generally 0.1 to 50 seconds.

[0160] Conventional zeolite catalysts comprising a matrix, an optional additive and at least one zeolite are generally used in the FCC process. The amount of the zeolite is variable, but is generally 3% to 60% by weight relative to the weight of the catalyst, typically 6% to 50% by weight, and most typically 10% to 45% by weight. The zeolite is generally dispersed in the matrix. The amount of the additive is generally 0% to 30% by weight, and typically 0% to 20% by weight relative to the weight of the catalyst. The amount of the matrix is supplemented to 100% by weight. The additive is generally selected from oxides of metals of Group IIa of the Periodic Table of Elements, such as magnesium oxide or calcium oxide, rare earth metal oxides and titanates of metals of Group IIa. Matrix is generally a mixture of silicon dioxide, aluminum oxide, silicon dioxide-aluminum oxide, silicon dioxide-magnesium oxide, clay or two or more of these products. The most commonly used zeolite is zeolite Y.

[0161] Hydrotreating

[0162] Hydrofinishing processes using hydrogen for hydrofinishing petroleum feedstocks and / or feedstocks obtained from biomass conversion are known to those skilled in the art and include processes such as hydrotreating, hydrocracking or hydroconversion.

[0163] Hydrotreating

[0164] The term "hydrotreating," commonly referred to as "HDT," refers to an operation whose primary purpose is to remove impurities such as sulfur, nitrogen, oxygen, halides, and trace metals from a feedstock and to saturate olefins and / or stabilize hydrocarbon free radicals by reacting them with hydrogen rather than with themselves. The primary purpose is not to change the boiling point range of the feedstock. Thus, hydrotreating specifically encompasses hydrodesulfurization (commonly referred to as "HDS") reactions, hydrodenitrogenation (commonly referred to as "HDN") reactions, and hydrodemetallization (commonly referred to as "HDM") reactions, along with hydrogenation, hydrodeoxygenation (commonly referred to as "HDO"), hydrodearomatization, hydroisomerization, and hydrodealkylation reactions. Hydrotreating is typically performed using a fixed bed reactor, although other reactors may also be used for hydrotreating, such as an ebullated bed hydrotreating reactor.

[0165] The feedstocks used in the hydrotreatment processes are, for example, gasoline, gas oils, vacuum gas oils, atmospheric residues, vacuum residues, atmospheric distillates, vacuum distillates, heavy fuel oils, oils, waxes and paraffins, waste oils, deasphalted residues or crude oils, feedstocks originating from thermal or catalytic conversion processes, lignocellulosic feedstocks or more generally, feedstocks derived from biomass, used alone or as mixtures. The feedstocks to be treated, in particular those mentioned above, generally contain heteroatoms such as sulfur, oxygen and nitrogen and, in the case of heavy feedstocks, they generally also contain metals.

[0166] A hydrotreating process particularly suitable for introducing partially hydrotreated pyrolysis oil according to the method of the present invention is a process for hydrotreating vacuum gas oil, diesel, kerosene or gasoline feedstocks and / or feedstocks derived from biomass, said feedstocks derived from biomass being selected from vegetable oils, oils from algae or algal oils, fish oils, waste cooking oils and fats of plant or animal origin.

[0167] The operating conditions used in the process for carrying out the hydrotreating reaction of the above feedstocks are generally as follows: the average temperature is advantageously between 180 °C and 450 °C, and preferably between 250 °C and 440 °C, the pressure is advantageously between 0.5 and 30 MPa, and preferably between 1 and 18 MPa, and the space velocity is advantageously between 0.1 and 20 h -1 between, and preferably between 0.2 and 5 h -1 between, and the hydrogen coverage is between 50 and 5000 Nm 3 , preferably between 80 and 2000 Nm 3 hydrogen / m 3 between feedstocks. The definitions of average temperature (WABT), HSV and hydrogen coverage correspond to those described above.

[0168] Conventional hydrotreating catalysts generally comprise an oxide support and an active phase based on Group VIB and Group VIII metals in oxide form and phosphorus. The Group VIB metal present in the active phase of the catalyst is preferably selected from molybdenum and tungsten. The Group VIII metal present in the active phase of the catalyst is preferably selected from cobalt, nickel and mixtures of these two elements. The active phase of the catalyst is preferably selected from combinations of elemental nickel-molybdenum, cobalt-molybdenum, nickel-tungsten, nickel-molybdenum-tungsten and nickel-cobalt-molybdenum, and very preferably, the active phase consists of a combination of cobalt and molybdenum, nickel and molybdenum, nickel and tungsten or nickel-molybdenum-tungsten.

[0169] Based on the total weight of the catalyst, expressed as the oxide of the Group VIII metal, the content of the Group VIII metal is between 1 wt% and 10 wt%, preferably between 1.5 wt% and 9 wt%, and more preferably between 2 wt% and 8 wt%. Based on the total weight of the catalyst, expressed as the oxide of the Group VIB metal, the content of the Group VIB metal is between 1 wt% and 40 wt%, preferably between 1 wt% and 35 wt%, and more preferably between 2 wt% and 30 wt%. The molar ratio of the Group VIII metal to the Group VIB metal in the fresh catalyst is generally between 0.1 and 0.8, preferably between 0.15 and 0.6.

[0170] Optionally, the hydrotreating catalyst may additionally exhibit a phosphorus content, based on the total weight of the fresh catalyst, generally between 0.1% and 20% by weight of P2O5, preferably between 0.2% and 15% by weight of P2O5, and very preferably between 0.3% and 11% by weight of P2O5. In addition, the phosphorus / (Group VIB metal) molar ratio is generally between 0.08 and 1, preferably between 0.1 and 0.9, and very preferably between 0.15 and 0.8.

[0171] The oxide support of the hydrotreating catalyst is generally a porous solid selected from the following: alumina, silica, silica-alumina, or titanium oxide or magnesium oxide used alone or in admixture with alumina or silica-alumina. According to a particularly preferred alternative form, the oxide support consists of alumina, silica, or silica-alumina.

[0172] The catalyst may also additionally contain, prior to sulfidation, at least one organic compound containing oxygen and / or nitrogen and / or sulfur. Such additives are known. Generally, the organic compound is selected from compounds containing one or more chemical functions selected from carboxyl, alcohol, thiol, thioether, sulfone, sulfoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea, and amide functions, or compounds containing a furan ring or sugar. Based on the total weight of the catalyst, the content of the organic compound containing oxygen and / or nitrogen and / or sulfur on the catalyst is between 1% and 30% by weight, preferably between 1.5% and 25% by weight, and more preferably between 2% and 20% by weight.

[0173] Hydrocracking

[0174] The hydrocracking process enables the conversion of petroleum fractions, in particular vacuum gas oils (VD), into lighter and more upgradeable products (gasoline, middle distillates). Other reactions are also carried out, such as the hydrogenation of olefins or aromatics, hydrodemetallization, hydrodesulfurization, hydrodenitrogenation, etc.

[0175] Hydrocracking is generally carried out using a fixed-bed reactor.

[0176] The feedstock used in the hydrocracking process is usually a hydrocarbon feedstock, in which at least 50% by weight of the compounds have an initial boiling point above 300 °C and a final boiling point below 650 °C. It can be selected from HCO (heavy recycle oil (heavy gas oil obtained from a fluid catalytic cracking unit)), vacuum distillate oil, such as gas oil obtained from the direct distillation of crude oil or from a conversion unit, such as a fluid catalytic cracking unit, coker or visbreaking unit, feedstock from an aromatic extraction unit, lubricating base oil or solvent dewaxing of a lubricating base oil, distillate oil from a fixed bed or fluidized bed desulfurization or hydroconversion process of atmospheric residue and / or vacuum residue and / or deasphalted oil, or the feedstock can be deasphalted oil or contain vegetable oil or be derived from the conversion of feedstock obtained from biomass. It can also be paraffins from the Fischer-Tropsch process. The hydrocarbon feedstock treated by the hydrocracking process according to the present invention can also be a mixture of the above feedstocks. Preferably, the feedstock is vacuum distillate oil.

[0177] A hydrocracking process particularly suitable for introducing pyrolysis oil with partial hydrotreatment according to the method of the present invention is a method for hydrotreating a vacuum gas oil feedstock.

[0178] The hydrocracking process is usually carried out at an average temperature between 250 °C and 480 °C, advantageously between 320 °C and 450 °C, preferably between 330 °C and 435 °C, at a pressure between 2 and 25 MPa, preferably between 3 and 20 MPa. The space velocity (HSV) of the feedstock relative to each catalyst volume is advantageously between 0.1 and 40 h -1 between, preferably between 0.2 and 12 h -1 between, very preferably between 0.4 and 6 h -1 between, and the hydrogen coverage is between 50 and 5000 Nm 3 preferably between 100 and 2000 Nm 3 hydrogen / m 3 feedstock. The definitions of the average temperature (WABT), HSV and hydrogen coverage correspond to those described above.

[0179] The hydrocracking process of vacuum distillate oil covers a range of pressures and conversion rates from mild hydrocracking to high-pressure hydrocracking. Mild hydrocracking is understood to mean hydrocracking that results in medium conversion rates (usually less than 40%) and operates at low pressure (preferably between 2 MPa and 6 MPa).

[0180] The hydrocracking process can be a "one - step" hydrocracking process or a "two - step" hydrocracking process. The "one - step" hydrocracking process first and usually includes exhaustive hydrotreating, the purpose of which is to perform strong HDN, strong HDS, and strong HDA on the feedstock before sending it to the hydrocracking catalyst. The "two - step" hydrocracking process includes a first step, the purpose of which is, as in the "one - step" process, to perform hydrotreating of the feedstock, but also to achieve a conversion of the feedstock of usually approximately 40% to 60%. The effluent obtained from the first step is then separated, usually by distillation, most commonly referred to as intermediate separation, the purpose of which is to separate the conversion products from the unconverted fractions. In the second step of the two - step hydrocracking process according to the present invention, only the unconverted feedstock fraction from the first step is treated.

[0181] The hydrocracking catalysts are of the bifunctional type: they combine an acidic function with a hydrogenation / dehydrogenation function. The acidic function is provided by a porous support, the surface area of which usually varies between 150 and 800 m 2 .g -1 and exhibits surface acidity, such as halogenated (especially chlorinated or fluorinated) alumina, combinations of boron and aluminum oxides, amorphous or crystalline mesoporous aluminosilicates, and zeolites dispersed in an oxide binder. The hydrogenation / dehydrogenation function is provided by the presence of an active phase based on at least one metal of Group VIB of the periodic table and optionally at least one metal of Group VIII. The most common formulations are of the nickel - molybdenum (NiMo) and nickel - tungsten (NiW) types, and less commonly of the cobalt - molybdenum (CoMo) type.

[0182] The metal content is usually as described for hydrotreating catalysts.

[0183] The hydrocracking catalysts can also contain phosphorus and / or organic compounds containing oxygen and / or nitrogen and / or sulfur, in amounts as described for hydrotreating catalysts.

[0184] Hydroconversion

[0185] The term "hydroconversion" refers to a process whose main purpose is to reduce the boiling - point range of a feedstock containing at least 50% of heavy hydrocarbon fractions with a boiling point of at least 300 °C or at least 450 °C, and in which a large part of the feedstock is converted into products with a boiling - point range lower than that of the starting feedstock. Hydroconversion usually involves the breaking of larger hydrocarbon molecules to obtain smaller molecular fragments with a smaller number of carbon atoms and a higher hydrogen - to - carbon ratio.

[0186] The feedstock used in the hydroconversion process is typically a heavy hydrocarbon fraction, at least 50% by weight of which has a boiling point temperature of at least 300 °C, preferably at least 350 °C, and more preferably at least 375 °C. Advantageously, the heavy hydrocarbon fraction of the feedstock consists of one or more vacuum residues. The vacuum residue can come directly from crude oil or from other refining units, such as, in particular, hydrotreating of residue, hydrocracking of residue, and visbreaking of residue. Preferably, the vacuum residue is the vacuum residue from the vacuum distillation column of the primary fractionation (straight run (SR)) of crude oil.

[0187] The heavy hydrocarbon fraction of the feedstock can also consist of aromatic fractions extracted from units for the production of lubricants, deasphalted oil (raffinate of the deasphalting unit) obtained from a deasphalting unit, or asphalt (residue of the deasphalting unit) obtained from a deasphalting unit.

[0188] The heavy hydrocarbon fraction of the feedstock can also consist of settling oil or recycle oil, which typically has a boiling range of 360 °C to 550 °C, such as FCC fluid catalytic cracking effluent, such as heavy recycle oil (HCO) or slurry oil (SLO).

[0189] The heavy hydrocarbon fraction comprises at least one of the following feedstocks and can consist of at least one of the following feedstocks, alone or as a mixture: crude oil, topped crude oil, atmospheric residue or vacuum residue from the atmospheric or vacuum distillation of crude oil (preferably from the primary fractionation of crude oil), atmospheric residue or vacuum residue from the atmospheric or vacuum distillation obtained during the direct liquefaction of coal, and preferably is the vacuum residue obtained from the vacuum distillation of crude oil (preferably obtained from the primary fractionation of crude oil).

[0190] A particularly suitable hydroconversion process for introducing partially hydrotreated pyrolysis oil according to the method of the present invention is a process for hydroconverting a vacuum residue feedstock.

[0191] The hydroconversion process is generally carried out at an average temperature between 340 °C and 550 °C, more preferably between 350 °C and 500 °C, preferably between 360 °C and 450 °C, at a pressure between 2 and 38 MPa, more preferably between 5 and 25 MPa, even more preferably between 6 and 20 MPa. The space velocity (HSV) of the feedstock relative to each catalyst volume is advantageously between 0.05 and 10 h -1 between, preferably between 0.1 and 5 h -1 between, even more preferably between 0.15 and 2 h -1 between, even more preferably between 0.15 and 1 h -1 between, and the hydrogen coverage is between 50 and 5000 Nm 3 preferably between 100 and 2000 Nm 3 and very preferably between 200 and 1000 Nm3 Hydrogen / m 3 The definitions of average temperature (WABT), HSV and hydrogen coverage correspond to those described above.

[0192] The hydroconversion section may comprise one or more ebullated bed or hybrid bed (ebullated bed and entrained bed) reactors containing at least one supported hydroconversion catalyst, the reactors being arranged in series and / or in parallel, such as for Process, such as in patent US4521295 or US4495060 or US4457831 or US4354852, in AIChE paper, March 19-23, 1995, Houston, Texas, paper number 46d, "Second generation ebullated bed technology", or by This is described in Chapter 3.5, “Hydroprocessing and Hydroconversion of Residue Fractions,” in the book “Catalysis by Transition Metal Sulfides,” published by Technip in 2013.

[0193] The hydroconversion section may also comprise one or more entrained bed reactors, also known as "slurry" reactors (reactors with three phases - liquid, gas, solid - where the solid and liquid phases may behave as homogeneous phases) or moving bed reactors (reactors with three phases where the solid catalyst moves downward and the liquid and gas flow upward or downward) or fixed bed reactors (reactors with three phases where the liquid feed flows radially downward onto a fixed bed of supported catalyst and hydrogen typically flows simultaneously with the liquid but in some cases may flow countercurrently).

[0194] The hydroconversion catalyst generally comprises an alumina support and at least one Group VIII metal selected from nickel and cobalt, preferably nickel, and at least one Group VIB metal selected from molybdenum and tungsten, preferably molybdenum. Preferably, the hydroconversion catalyst comprises nickel as the Group VIII element and molybdenum as the Group VIB element.

[0195] The metal content is generally as described for the hydrotreating catalyst.

[0196] The hydroconversion catalyst may also contain phosphorus and / or oxygen- and / or nitrogen- and / or sulfur-containing organic compounds in amounts as described for the hydrotreating catalyst.

[0197] Analytical methods used

[0198] Analytical methods and / or standards for determining the properties of various streams, in particular the properties of the raw materials to be treated and the effluents, are known to those skilled in the art. They are listed in particular in Table 1 for informational purposes. Other methods considered equivalent may also be used, in particular equivalent IP, EN or ISO methods:

[0199] Table 1

[0200]

[0201]

[0202] (1) The MAV method is described in the paper: C. López-García et al., Near Infrared Monitoring of Low Conjugated Diolefins Content in Hydrotreated FCC Gasoline Streams, Oil & Gas Science and Technology–Rev. IFP, Vol. 62 (2007), No. 1, pp. 57-68

[0203] List of attached pictures

[0204] Figures 1 to 2 The details of the elements mentioned in the drawings enable a better understanding of the present invention, but the present invention is not limited to Figures 1 to 2 The various embodiments shown can be used alone or in combination with each other without limitation to the combination.

[0205] Figure 1 A diagram representing a general embodiment of the method of the present invention comprising:

[0206] - step a) of hydrotreating the pyrolysis oil 1 in the presence of a hydrogen-rich gas 2 and optionally an amine provided by stream 3 and optionally a sulfiding agent provided by stream 4;

[0207] a separation / washing step b) to which is supplied part of the hydrotreated effluent 5 from the hydrotreatment step a) and in the presence of an aqueous solution 6, so as to obtain at least a gaseous effluent 7, an aqueous effluent 8 and part of the hydrotreated hydrocarbon effluent 9, a portion 9a of which can be recycled to step a);

[0208] - step c), fluidized catalytic cracking or hydrorefining of petroleum feedstocks and / or feedstocks 10 obtained from biomass conversion, wherein at least a portion, and preferably all, of the partially hydrotreated hydrocarbon effluent 9 from step b) is introduced as a co-feed, said partially hydrotreated hydrocarbon effluent 9 from step b) being introduced without previously undergoing a further hydrotreatment step carried out at higher temperature and / or pressure, in order to increase the yield of the product 11 obtained from step c), in the case of FCC in particular propylene.

[0209] Figure 2 Representative based on Figure 1 The figure shows a diagram of a specific embodiment of the process according to the invention. The figure shows the process according to the invention integrated in an existing refinery, which comprises hydrotreating of vacuum gas oil, followed by separation of the hydrotreated vacuum gas oil and then its introduction into an FCC to produce, inter alia, gasoline and olefins.

[0210] Hydrotreating step a) and separation / washing step b) as Figure 1 Proceed as described in .

[0211] The vacuum gas oil 12 is introduced into a hydrotreatment unit 13 in the presence of fresh hydrogen 14 pressurized to the desired pressure by means of a compressor 15. The compressor 15 is also supplied with the gaseous effluent 7 obtained from separation step b) of the process according to the invention, which essentially contains hydrogen, optionally after a purification step (not shown).

[0212] The stream 2 comprising hydrogen supplied to step a) of hydrotreating the pyrolysis oil according to the process of the invention can come from a compressor 15. This enables the use of a single hydrogen compressor.

[0213] The hydrotreated effluent 16 is then subjected to a separation 17 so as to be able to recover at least a light fraction 18 (gas and naphtha), a middle fraction 19 (gas oil) and a hydrotreated vacuum gas oil fraction 10 .

[0214] The hydrotreated vacuum gas oil fraction 10 is then introduced into the catalytic cracking unit of step c) as a mixture with the partly hydrotreated hydrocarbon effluent 9 from step b).

[0215] exist Figure 1 and 2 Only the main steps and main streams are shown in order to facilitate a better understanding of the present invention. It is clearly understood that all equipment pieces required for operation are present (drums, pumps, exchangers, furnaces, columns, etc.), even if they are not shown. It is also understood that the hydrogen-rich gas stream (feed or recycle stream) as described above can be injected at the inlet of each reactor or catalyst bed or between two reactors or two catalyst beds. Example

[0216] The pyrolysis feedstock processed in this method is plastic pyrolysis oil having the characteristics shown in Table 2 (i.e., containing 100% by weight of said plastic pyrolysis oil).

[0217] Table 2: Characteristics of the pyrolysis feedstock

[0218]

[0219]

[0220] Subject the pyrolysis feedstock to a hydrotreating step a) carried out in a fixed-bed reactor and under different operating conditions shown in Table 3 in the presence of hydrogen and a NiMo-on-alumina hydrotreating catalyst.

[0221] Table 3: Conditions for hydrotreating step a)

[0222]

[0223] At the end of the hydrogenation step a), the conversion rates observed for chlorine, dienes, and olefins (= (initial concentration - final concentration) / initial concentration) are shown in Table 4.

[0224] Table 4: Conversion rates of entities during hydrotreating step a)

[0225]

[0226] Subject the effluent from hydrotreating step a) to a separation step b): Inject a water stream into the effluent from hydrotreating step a); then treat the mixture in an acid gas scrubber and a separation tank.

[0227] The yields of the various fractions obtained after separation are shown in Table 5 (the yield corresponds to the ratio of the weight-based amount of the various products obtained to the weight of the feedstock upstream of step a), expressed as a percentage and denoted as % w / w).

[0228] Table 5: Yields of the various products obtained after separation

[0229] <![CDATA[Gas fraction (NH3 + H2S + H2O + C1-C4)]]> % w / w 2.42 Liquid fraction % w / w 99.31

[0230] The characteristics of the liquid fraction obtained after separation step b) are shown in Table 6:

[0231] Table 6: Characteristics of the liquid fraction

[0232]

[0233]

[0234] The effluent from step b) was then mixed with an FCC oil feedstock having a chlorine content of 1 ppm by weight in a weight ratio of 10% oil to 90% oil feedstock. A mixture containing less than 5 ppm by weight of chlorine was obtained (for all examples) and introduced into a fluid catalytic cracking unit without fear of corrosion problems related to the chlorine content.

[0235] However, in the case of Examples 2 and 3 according to the present invention, olefins and diolefins are retained, which is advantageous because they are compounds that can be upgraded in FCC to produce propylene. In addition, the process according to the present invention uses less energy (temperature of step a)) and less hydrogen (H2 consumption).

[0236] Example 3, carried out under very mild conditions of temperature and pressure, shows that it is possible to obtain adequate dechlorination while retaining as much of the olefinic and diolefinic oil as possible, and while using lower pressures (and therefore less energy) than in Example 2.

Claims

1. A method for treating a pyrolysis feedstock, the pyrolysis feedstock comprising plastics and / or tires and / or solid recovered fuel pyrolysis oil containing halogenated compounds, the method comprising: a) A hydrotreating step carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst, feeding at least the pyrolysis feedstock and a gas stream containing hydrogen to the hydrotreating reaction section, the hydrotreating reaction section being used at an average temperature between 100 °C and 220 °C, a hydrogen partial pressure between 1.0 and 3.0 MPa absolute pressure, and a space velocity between 0.05 and 5 h -1 between, with a hydrogen coverage rate between 5 and 50 Nm 3 hydrogen / m 3 between the pyrolysis feedstocks to obtain a partially hydrotreated effluent having hydrocarbon compounds with a reduced halogen content b) A separation step, to which is fed a portion of the hydrotreated effluent and an aqueous solution from step a) to obtain at least a gas effluent, an aqueous effluent, and a portion of the hydrotreated hydrocarbon effluent. c) A fluid catalytic cracking or hydrotreating step of a petroleum feedstock and / or a feedstock obtained from biomass conversion, wherein at least a portion of the portion of the hydrotreated hydrocarbon effluent from step b) is introduced as a co-feed, and the portion of the hydrotreated hydrocarbon effluent from step b) is introduced without first undergoing another hydrotreating step at a temperature and / or pressure higher than the temperature and / or pressure of step a), and the mixture of the petroleum feedstock and / or the feedstock obtained from biomass conversion and the portion of the hydrotreated hydrocarbon effluent from step b) has a halogen content of less than or equal to 10 weight ppm.

2. The method according to the preceding claim, wherein the weight ratio of the flow rate of the portion of the hydrotreated hydrocarbon effluent from step b) introduced in step c) to the flow rate of the petroleum feedstock and / or the feedstock obtained from biomass conversion is less than 1.

3. The method according to any one of the preceding claims, wherein the pyrolysis feedstock consists of plastics and / or tires and / or solid recovered fuel pyrolysis oil.

4. The method according to any one of the preceding claims, wherein the content of the halogenated compounds in the pyrolysis feedstock is between 1 and 5000 weight ppm.

5. The method according to any one of the preceding claims, wherein a stream containing nitrogen compounds and / or sulfur compounds is injected upstream of step a).

6. The method according to any one of the preceding claims, wherein the hydrotreating catalyst in step a) comprises a support selected from alumina, silica, silica-alumina, magnesia, clay, and mixtures thereof, and a hydrogenation-dehydrogenation functionality containing at least one Group VIII element and at least one Group VIB element, or at least one Group VIII element.

7. The method according to any one of the preceding claims, which includes at least one pretreatment step a0) of a feedstock comprising plastics and / or tires and / or SRF pyrolysis oil, the pretreatment step being carried out upstream of step a) and including an adsorption step and / or a filtration step and / or a centrifugation step and / or a sedimentation step and / or an electrostatic separation step and / or a step of washing with an aqueous solution and / or a gas stripping step.

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

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

10. The method according to any one of the preceding claims, wherein the reaction section of step a) uses at least two reactors operating in a replaceable mode.

11. The method according to any one of the preceding claims, wherein the fluid catalytic cracking step c) is carried out in a fluid catalytic cracking reaction section in a substantially vertical reactor in an upward flow mode or a downward flow mode in the presence of a zeolite catalyst at a reactor temperature between 450 °C and 600 °C with a contact time in the reactor of less than 1 minute.

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

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

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

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