FR3130836A1 - HYDROCONVERSION IN BUBBLE BED OR BUBBLE-ENCOURAGED HYBRID OF A FEED COMPRISING A PLASTIC FRACTION - Google Patents

Abstract

The present invention relates to a process for the hydroconversion of a feed comprising a plastic fraction (102), in particular from plastic waste, and a heavy hydrocarbon fraction (101), in particular a heavy hydrocarbon fraction containing a part of at least 50% by weight, preferably at least 80% by weight, having a boiling point of at least 300°C. Hydroconversion uses one or more bubbling bed or bubbling-entrained hybrid bed reactors (20), and preferably two successive hydroconversion steps, to produce higher quality, higher boiling point materials. lower, for example for fuel production purposes, while allowing the recovery of plastic waste. Figure 1A to be published

Description

HYDROCONVERSION IN BUBBLE BED OR BUBBLE-ENCOURAGED HYBRID OF A FEED COMPRISING A PLASTIC FRACTION

The present invention relates to the field of the hydroconversion of feedstocks comprising a plastic fraction, in particular from plastic waste, and a heavy hydrocarbon fraction, in particular a heavy hydrocarbon fraction containing a part of at least 50% by weight, of preferably at least 80% by weight, having a boiling point of at least 300°C.

The heavy hydrocarbon fraction can be a crude oil or be obtained from the distillation and/or the refining of a crude oil, typically a topped crude oil, a residue from the atmospheric and/or vacuum distillation of a crude oil . This heavy fraction of hydrocarbons is associated with a fraction of plastic(s).

In particular, the present invention relates to a process for the hydroconversion of such a mixed feed, comprising at least one hydroconversion step implementing one or more reactors operating in a bubbling bed or in a bubbling-entrained hybrid bed, and preferably two successive hydroconversion steps, with a view to producing materials of higher quality, with a lower boiling point, for example for the purposes of producing fuels, while allowing the recovery of plastic waste.

For several years, we have seen the appearance, within the fuel and chemical sectors, of processes incorporating products other than traditional petroleum products, for example products of renewable origin such as lignocellulosic biomass, or products of the plastic waste type, in addition to or as a substitute for products of fossil origin.

For example, patent US8623102 is known relating to a process for liquefying biomass chosen from algae, lignocellulosic biomass or one or more constituents of lignocellulosic biomass chosen from the group formed by cellulose, hemicellulose and/or lignin to produce fuel bases, said process comprising two successive hydroconversion steps under high hydrogen pressure in bubbling bed reactors using a supported catalyst of the oil residue hydroconversion type and a suspension composed of the biomass and a solvent.

In particular, in a context of circular economy and waste reduction, there is particular attention paid to plastics, which are classically petroleum-derived products, in order to recover them.

This recovery of plastic waste may consist of transforming said plastics, by mechanical and/or chemical means, in order to once again allow the production of plastics or plastic-based objects. This is the recycling of plastic waste.

This recovery of plastic waste can also follow the path of energy recovery, in particular for plastic waste that is not recyclable or difficult to recycle, as an alternative, in some cases, to landfill.

Typically, the energy recovery of plastic waste consists of producing energy, in the form of electricity and/or heat. For example, it is known to subject plastics from collection and sorting channels to a pyrolysis step to produce, among other things, plastic pyrolysis oils, which are generally burned to generate electricity and/or used as fuel in industrial or district heating boilers.

In the field of hydroconversion, i.e. the conversion of hydrocarbon feeds under high hydrogen pressure into products with lower boiling point ranges than those of the original feed, application WO2020129020 describes a hydroconversion process of a mixture of polymers based on the use of an entrained catalyst, also known as a “slurry” hydroconversion process. The very small catalyst is dispersed in the reaction medium, distributed uniformly in the reactor, and entrained with the products leaving the reactor. According to this process, a mixture of plastics is treated according to slurry technology based on the use of a reactor operating with an entrained catalyst, and is transformed into hydrocarbons having a boiling temperature varying from 65°C to 175°C, corresponding to a naphtha cut. It is ultimately a process for the chemical recycling of plastic waste, making it possible to transform used plastics into a naphtha fraction, which is one of the main reagents for the production of plastics. The feedstock in the slurry hydroconversion process according to application WO2020129020 is a solid mixture of polymers, which can be mixed with a vacuum residue, and which is introduced in the form of slurry (suspension of solids) into a reactor operating in an entrained bed . Although slurry processes are known to process heavy loads and achieve higher conversion rates than other processes, for example hydroconversion processes using boiling bed reactors implementing a supported catalyst maintained in the reactor, a major drawback of slurry processes lies in the complex and costly management of the catalyst entrained with the conversion products, in particular its separation from the final products.

Objects and Summary of the Invention

The present invention relates to the field of the recovery of heavy loads that are difficult to recover such as petroleum residues, which generally contain high levels of impurities such as metals, sulfur, nitrogen, Conradson carbon and asphaltenes, in order to convert them into lighter products that can be used as fuels, for example to produce gasoline or diesel, or raw materials for the petrochemical industry.

The inventors have demonstrated that, surprisingly, it was possible to incorporate a fraction of plastics derived from waste, in different ways, into a heavy hydrocarbon feedstock traditionally treated in a bubbling bed or hybrid bubbling-bed hydroconversion process. driven, without significantly degrading the overall load conversion.

The present invention thus proposes a process for the hydroconversion of a heavy charge of hydrocarbons in a bubbling or bubbling-entrained hybrid bed, said charge including a fraction of plastics from waste, thus allowing the production of fuel bases and other recoverable hydrocarbons ( light hydrocarbons, distillates intended for a steam cracker, in particular for the production of recycled polyolefins, bases for the production of bitumen, lubricants, etc.) while ensuring the recovery of plastic waste which could otherwise be destined for landfill, incineration. More generally, the invention contributes to increasing the share of plastic waste recycling while treating plastic impurities.

Thus, to achieve at least one of the abovementioned objectives, among others, the present invention proposes, according to a first aspect, a process for the hydroconversion of a feedstock comprising the following successive steps:
(a) conditioning and introducing said feed into a first hydroconversion section comprising at least a first bubbling-bed or bubbling-entrained hybrid-bed hydroconversion reactor comprising a porous supported first hydroconversion catalyst, said feed comprising between 1% and 50% by weight of a plastic fraction and 50% and 99% by weight of a heavy hydrocarbon fraction containing a part of at least 50% by weight having a boiling point of at minus 300°C, and containing sulfur, and nitrogen;
(b) a first stage of hydroconversion of said feedstock in the presence of hydrogen in said first hydroconversion section to obtain a first hydroconverted effluent;
(c) optionally, a step of separating part or all of said first effluent resulting from step (b), to form at least one heavy cut boiling mainly at a temperature greater than or equal to 350° C.;
(d) optionally, a second hydroconversion stage in a second hydroconversion section comprising at least one second bubbling-bed or bubbling-entrained hybrid-bed hydroconversion reactor of part or all of said first effluent resulting from step (b) or optionally said heavy cut from step (c), said second hydroconversion reactor comprising a second supported porous catalyst and operating in the presence of hydrogen, to produce a second hydroconverted effluent;
step (b) and optional step (d) being carried out at an absolute pressure between 2 MPa and 38 MPa, at a temperature between 300°C and 550°C, at an hourly space velocity relative to the volume of each hydroconversion reactor comprised between 0.05 h ^-1 and 10 h ^-1 , and with a quantity of hydrogen comprised between 50 Nm ³ /m ³ and 5000 Nm ³ /m ³ ,
(e) a step of fractionating all or part of said first hydroconverted effluent from step (b) or said second hydroconverted effluent from step (d), in a fractionation section, to produce at least one liquid product which boils predominantly at a temperature greater than or equal to 350°C, said heavy liquid product containing a residual fraction which boils at a temperature greater than or equal to 540°C.

According to one or more implementations of the invention, in step (a), the plastic fraction and the heavy hydrocarbon fraction of the feed are introduced mixed into said at least one first hydroconversion reactor of the first section of hydroconversion.

According to one or more implementations of the invention, in step (a), the plastic fraction in the form of solid particles is mixed with the heavy fraction of hydrocarbons so as to form a suspension, said suspension being heated until at a temperature above the melting point of said plastic fraction to form the charge introduced into the first hydroconversion reactor.

According to one or more implementations of the invention, in step (a), the plastic fraction in the form of solid particles is mixed beforehand with a plastic diluent to form a first suspension, then said first suspension is mixed with the fraction heavy with hydrocarbons so as to form a second suspension, said second suspension being heated to a temperature above the melting temperature of said plastic fraction to form the charge introduced into the first hydroconversion reactor

According to one or more implementations of the invention, in step (a), the plastic fraction in the form of solid particles (), preferably previously mixed with a plastic diluent to form a suspension, is heated to a temperature above the melting temperature of said plastic fraction to form a molten plastic fraction, then said molten plastic fraction is mixed with the heavy hydrocarbon fraction so as to form the charge introduced into the first hydroconversion reactor.

According to one or more implementations of the invention, in step (a), the plastic fraction in the form of solid particles is heated to a temperature above the melting point of said plastic fraction to form a plastic fraction then said molten plastic fraction is mixed with a plastic diluent to form a dilute molten plastic fraction mixed with the heavy hydrocarbon fraction to form the charge introduced into the first hydroconversion reactor.

According to one or more implementations of the invention, in step (a), the plastic fraction and the heavy hydrocarbon fraction of the feed are introduced separately into said at least one first hydroconversion reactor of the first section of hydroconversion.

According to one or more implementations of the invention, in step (a), the plastic fraction in the form of solid particles is sent to an extruder, preferably with a plastic diluent, in which it is gradually heated until a temperature above the melting temperature of said plastic fraction, and pressurizing said first hydroconversion reactor during conveying, preferably for a period of less than 15 minutes, and said extruded plastic fraction is introduced into the first reactor of hydroconversion.

According to one or more embodiments of the invention, in step (a), the plastic fraction in the form of solid particles is mixed with a plastic diluent in a mixing section and heated in a heating section to a temperature above at the melting temperature of said plastic fraction, preferably between 60°C and 295°C, before its introduction into the first hydroconversion reactor, the heating step possibly being carried out before or after mixing with the plastic diluent , and preferably after mixing with plastic thinner.

According to one or more implementations of the invention, in step (a), the plastic fraction in the form of solid particles is sent beforehand to a mixer to be mixed with a plastic diluent and form a suspension, preferably at a temperature greater than or equal to ambient temperature and lower than the melting temperature of said plastic fraction, and said plastic fraction in the form of a suspension is introduced into the first hydroconversion reactor.

According to one or more implementations of the invention, in step (a), the plastic fraction in the form of solid particles is mixed beforehand with a plastic diluent and with the first supported porous hydroconversion catalyst in a distribution box and mixing to form a suspension, then said suspension is introduced into the first hydroconversion reactor via the means for injecting the catalyst into the first hydroconversion reactor.

According to one or more implementations of the invention, the filler comprises between 5% and 30% by weight, preferably between 5% and 20% by weight, of said plastic fraction, and between 70% and 95% by weight, preferably between 80% and 95% by weight of said heavy hydrocarbon fraction.

According to one or more implementations of the invention, the method comprises the separation step (c) separating part, or all, of the first hydroconverted effluent () from step (b) to produce at least the heavy cut boiling mainly at a temperature greater than or equal to 350° C., and comprises the second stage of hydroconversion (d) of said heavy cut.

According to one or more implementations of the invention, the hydroconversion reactor(s) of first hydroconversion section in step (b), and optionally in hydroconversion step (d), are reactors with bubbling-entrained hybrid bed, said method further comprising a step of introducing a catalyst precursor, preferably molybdenum 2-ethylhexanoate, before injecting said charge into said at least one first bed reactor bubbling-entrained hybrid of the first hydroconversion section such that a colloidal or molecular catalyst, preferably comprising molybdenum disulfide, is formed when said feedstock reacts with sulfur.

According to one or more implementations of the invention, the first hydroconversion catalyst, and optionally the second hydroconversion catalyst, contains at least one non-noble group VIII metal chosen from nickel and cobalt, preferably nickel, and at least one metal from group VIB chosen from molybdenum and tungsten, preferably molybdenum, and comprising an amorphous support, preferably alumina.

According to one or more implementations of the invention, the heavy hydrocarbon fraction of the feed comprises, and may consist of, at least one of the following feeds, alone or as a mixture: a crude oil, a crude oil topped, an atmospheric residue or a vacuum residue from the atmospheric or vacuum distillation of a crude oil (preferably from the primary fractionation of crude oil), an atmospheric residue or a vacuum residue from the distillation atmospheric or vacuum obtained during a direct coal liquefaction process, and preferably is a vacuum residue from the vacuum distillation of a crude oil (preferably from the primary fractionation of crude oil).

According to one or more implementations of the invention, the heavy hydrocarbon fraction of the feed comprises sulfur at a content greater than 0.5% by weight and nitrogen at a content of between 1 ppm and 8000 ppm by weight, and preferably a Conradson carbon content of at least 3% by weight, and/or a C ₇ asphaltene content of at least 1% by weight, and/or a metal content of at least 20 ppm wt.

According to one or more implementations of the invention, the plastic fraction of the filler comprises one or more polymers chosen from the list consisting of alkene polymers, diene polymers, vinyl polymers, styrenic polymers.

According to one or more implementations of the invention, the plastic fraction of the filler comprises at least 50% by weight, preferably at least 80% by weight, more preferably at least 90% by weight, and very preferably at least 94 % by weight, of polyolefins relative to the total weight of the plastic fraction of the filler.

According to one or more implementations of the invention, the polyolefins of the plastic fraction of the filler are chosen from the list consisting of polyethylene (PE), polypropylene (PP) and/or copolymers of ethylene and propylene.

According to one or more implementations of the invention, the plastic diluent is hydrocarbon or a mixture of liquid hydrocarbons, and preferably the plastic diluent is a hydrocarbon oil composed of hydrocarbons of which at least 50% by weight, relative to the total weight of the hydrocarbon oil, have a boiling point of between 180°C and 540°C, preferably chosen from the list consisting of a vacuum gas oil (VGO), a settling oil or a recycling oil such as FCC fluidized bed catalytic cracking effluent such as heavy recycle oil (HCO) or light recycle oil (LCO), pyrolysis oil from a hydrocracker, light gas oil, atmospheric residue, under vacuum, a deasphalted oil, and a resin, and more preferably the plastic diluent is an LCO, an HCO or a VGO.

According to one or more implementations of the invention, the plastic diluent is a hydrocarbon or a mixture of liquid hydrocarbons comprising, e.g. consisting of, xylene, toluene, a gasoline, or their mixtures.

Other objects and advantages of the invention will appear on reading the following description of examples of particular embodiments of the invention, given by way of non-limiting examples, the description being made with reference to the appended figures described below. -After.

List of Figures

Figures 1A to 1D illustrate the first embodiment of the hydroconversion process according to the invention, in which the heavy fraction and the plastic fraction of the feed are injected separately into the hydroconversion reactor, i.e. without being mixed before their introduction in the hydroconversion reactor. We will speak of direct injection to refer to this first embodiment.

Figures 2A to 2E illustrate the second embodiment of the hydroconversion process according to the invention, in which the heavy fraction and the plastic fraction of the feed are mixed before their introduction into the hydroconversion reactor. We will speak of indirect injection to refer to this second embodiment.

There is a functional diagram illustrating a first variant of the first embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is heated before its introduction, in a substantially liquid form, into the hydroconversion reactor.

There is a functional diagram illustrating a second variant of the first embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is mixed with a diluent then heated to be injected in a substantially liquid form into the hydroconversion reactor.

There is a functional diagram illustrating a third variant of the first embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is injected into the hydroconversion reactor in the form of a suspension.

There is a functional diagram illustrating a fourth variant of the first embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is injected into the hydroconversion reactor in the form of a suspension via the means for injecting the supported catalyst.

There is a functional diagram illustrating a first variant of the second embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is mixed in solid form with the heavy fraction.

There is a functional diagram illustrating a second variant of the second embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is mixed in solid form with a diluent then mixed with the heavy fraction.

There is a functional diagram illustrating a third variant of the second embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is heated so as to be in a substantially liquid form before being mixed with the heavy fraction.

There is a functional diagram illustrating a fourth variant of the second embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is mixed in solid form with a diluent then heated so as to be in substantially liquid form before being mixed with the heavy fraction.

There is a block diagram illustrating a fifth variant of the second embodiment of the hydroconversion process according to the invention, according to which the plastic fraction is heated so as to be in a substantially liquid form, then mixed with a diluent before being mixed to the heavy fraction.

In the figures, the same references designate identical or similar elements.

Claims (15)

Process for the hydroconversion of a feed comprising the following successive steps:
(a) conditioning and introducing said feed into a first hydroconversion section (20) comprising at least a first bubbling-bed or bubbling-entrained hybrid-bed hydroconversion reactor comprising a porous supported first hydroconversion catalyst , said feed comprising between 1% and 50% by weight of a plastic fraction and 50% and 99% by weight of a heavy hydrocarbon fraction containing a portion of at least 50% by weight having a boiling point at least 300°C, and containing sulfur and nitrogen;
(b) a first stage of hydroconversion of said feedstock in the presence of hydrogen in said first hydroconversion section (20) to obtain a first hydroconverted effluent (105);
(c) optionally a step of separating part or all of said first effluent resulting from step (b), to form at least one heavy cut boiling mainly at a temperature greater than or equal to 350° C.;
(d) optionally a second hydroconversion step in a second hydroconversion section comprising at least one second bubbling bed or bubbling-entrained hybrid bed hydroconversion reactor of part or all of said first effluent resulting from the step (b) or optionally of said heavy cut from step (c), said second hydroconversion reactor comprising a second supported porous catalyst and operating in the presence of hydrogen, to produce a second hydroconverted effluent;
step (b) and optional step (d) being carried out at an absolute pressure between 2 MPa and 38 MPa, at a temperature between 300°C and 550°C, at an hourly space velocity relative to the volume of each hydroconversion reactor comprised between 0.05 h ^-1 and 10 h ^-1 , and with a quantity of hydrogen comprised between 50 Nm ³ /m ³ and 5000 Nm ³ /m ³ ,
(e) a step of fractionating all or part of said first hydroconverted effluent from step (b) or said second hydroconverted effluent from step (d), in a fractionation section (30), to produce at least a heavy liquid product (106b) which boils predominantly at a temperature greater than or equal to 350°C, said heavy liquid product containing a residual fraction which boils at a temperature greater than or equal to 540°C. Process according to Claim 1, in which, in step (a), the plastic fraction and the heavy hydrocarbon fraction of the charge (114, 117, 120, 122, 125) are introduced mixed into the said at least one first hydroconversion reactor of the first hydroconversion section (20). Process according to Claim 2, in which, in step (a), the plastic fraction in the form of solid particles (102) is mixed with the heavy hydrocarbon fraction (101) so as to form a suspension (113), said suspension (113) being heated to a temperature above the melting temperature of said plastic fraction to form the charge (114) introduced into the first hydroconversion reactor. Process according to Claim 2, in which, in step (a), the plastic fraction in the form of solid particles (102) is mixed beforehand with a plastic diluent (107) to form a first suspension (115), then said first suspension (115) is mixed with the heavy hydrocarbon fraction (101) so as to form a second suspension (116), said second suspension (116) being heated to a temperature above the melting temperature of said plastic fraction to form the charge (117) introduced into the first hydroconversion reactor. Process according to Claim 2, in which, in step (a), the plastic fraction in the form of solid particles (102), preferably previously mixed with a plastic diluent (107) to form a suspension (120), is heated to a temperature above the melting temperature of said plastic fraction to form a molten plastic fraction (118, 121), then said molten plastic fraction (118, 121) is mixed with the heavy hydrocarbon fraction (101) of so as to form the charge (119, 122) introduced into the first hydroconversion reactor. A method according to claim 2, wherein in step (a), the plastic fraction in the form of solid particles (102) is heated to a temperature above the melting temperature of said plastic fraction to form a plastic fraction (123), then said molten plastic fraction (123) is mixed with a plastic diluent (107) to form a dilute molten plastic fraction (124) mixed with the heavy hydrocarbon fraction (101) to form the filler (125) introduced into the first hydroconversion reactor Process according to Claim 1, in which, in step (a), the plastic fraction (103, 109, 110, 112) and the heavy hydrocarbon fraction (101) of the feed are introduced separately into the said at least one first hydroconversion reactor of the first hydroconversion section (20). Process according to Claim 7, in which, in step (a), the plastic fraction in the form of solid particles (102) is sent to an extruder (10), preferably with a plastic diluent (107), in which it is gradually heated to a temperature above the melting temperature of said plastic fraction, and pressurized in said first hydroconversion reactor during conveying, preferably for a period of less than 15 minutes, and said extruded plastic fraction (103) is introduced into the first hydroconversion reactor. A method according to claim 7, wherein in step (a) the plastic fraction in the form of solid particles is mixed with a plastic diluent (107) in a mixing section (11) and heated in a heating section ( 12) at a temperature above the melting temperature of said plastic fraction, preferably between 60°C and 295°C, before its introduction into the first hydroconversion reactor, the heating step possibly being carried out before or after mixing with Plastic Thinner, and preferably after mixing with Plastic Thinner. Process according to Claim 7, in which, in step (a), the plastic fraction in the form of solid particles is previously sent to a mixer (13) to be mixed with a plastic diluent (107) and form a suspension (110 ), preferably at a temperature above or equal to ambient temperature and below the melting temperature of said plastic fraction, and said plastic fraction in the form of a suspension (110) is introduced into the first hydroconversion reactor. Process according to Claim 7, in which, in step (a), the plastic fraction in the form of solid particles is mixed beforehand with a plastic diluent (107) and with the first porous supported hydroconversion catalyst in a distribution box and mixing (14) to form a suspension (112), then said suspension (112) is introduced into the first hydroconversion reactor via the means for injecting the catalyst into said first hydroconversion reactor. Process according to any one of the preceding claims, in which the filler comprises between 5% and 30% by weight, preferably between 5% and 20% by weight, of the said plastic fraction, and between 70% and 95% by weight, preferably between 80% and 95% by weight of said heavy hydrocarbon fraction. Process according to any one of the preceding claims, comprising the separation step (c) separating a part, or all, of the first hydroconverted effluent (105) resulting from step (b) to produce at least the boiling heavy cut mainly at a temperature greater than or equal to 350° C., and comprising the second stage of hydroconversion (d) of said heavy cut. A process according to any preceding claim, wherein the first hydroconversion section hydroconversion reactor(s) (20) in step (b), and optionally in hydroconversion step (d), are bubbling-entrained hybrid bed reactors, said method further comprising a step of introducing a catalyst precursor (104), preferably molybdenum 2-ethylhexanoate, before injecting said charge into said at least at at least a first bubbling-entrained hybrid bed reactor of the first hydroconversion section (20), such that a colloidal or molecular catalyst, preferably comprising molybdenum disulfide, is formed when said feed reacts with sulfur. Process according to any one of the preceding claims, in which the first hydroconversion catalyst, and optionally the second hydroconversion catalyst, contains at least one non-noble Group VIII metal chosen from nickel and cobalt, preferably nickel, and at least one metal from group VIB chosen from molybdenum and tungsten, preferably molybdenum, and comprising an amorphous support, preferably alumina.