PROCESS FOR COKEFACTION OF FOSSIL-DERIVED HYDROCARBONS IN THE PRESENCE OF TIRE FRAGMENTS

Abstract

The invention relates to a process for producing hydrocarbon fluids from a heavy hydrocarbon feedstock of fossil origin and tire fragments, comprising: a) a step of supplying tire fragments, b) a coking step in a coking unit during which said heavy hydrocarbon feedstock of fossil origin undergoes thermal cracking under coking conditions in the presence of the tire fragments supplied by step a), and an at least partially cracked effluent and a solid residue are produced, c) a fractionation step in which the effluent from step b) is fractionated into at least one liquid hydrocarbon fraction. Abstract figure: Figure 1

Description

Title of the invention: PROCESS FOR COKEFACTION OF FOSSIL-DERIVED HYDROCARBONS IN THE PRESENCE OF TIRE FRAGMENTS technical field

[0001] The present invention relates to a process for the thermal cracking of fossil-based hydrocarbons in the presence of tire fragments. Context of the invention

[0002] There is an important need, also encouraged by regulations, to limit tire waste in landfills and to recycle it.

[0003] Tires have the advantage of possessing a non-negligible biogenic fraction (rubber from the Hevea tree), which allows them to be recycled into hydrocarbon products that are partly bio-based.

[0004] One possible method for recycling tires is to obtain tire oil by pyrolysis, steam thermolysis, solvolysis, or hydrothermal liquefaction. However, the tire oil obtained generally contains large quantities of dienes and heteroatoms, including nitrogen, sulfur, silicon, and metals, which are contaminants for the catalysts in the hydrotreating processes typically used in subsequent recycling processes. The presence of dienes in these oils also makes them unstable, with a high risk of gum formation during high-temperature treatments, and consequently, of clogging the installation and / or fouling the catalysts used.

[0005] In addition, existing recycling processes are relatively energy-intensive.

[0006] Thus, the preparation of hydrocarbon fuels or fluids from molecules derived from tires constitutes a real economic, environmental and strategic challenge.

[0007] There is therefore a need to propose a process for recycling tires, particularly within the fossil hydrocarbon products of a refinery. Description of the invention

[0008] The invention proposes a method for manufacturing hydrocarbon fluids from a heavy hydrocarbon feedstock of fossil origin and tire fragments.

[0009] This process includes: a) a step of supplying tire fragments, b) a coking step carried out in a coking unit during which said heavy fossil-based hydrocarbon feedstock, or a fraction thereof, undergoes thermal cracking in coking conditions in the presence of the tire fragments supplied by step a), and an at least partially cracked effluent and a solid residue are produced, c) a fractionation step in which the effluent from step b) is fractionated into at least one liquid hydrocarbon fraction.

[0010] In one embodiment, prior to step b), said heavy fossil-based hydrocarbon feedstock may be fractionated into a heavy fraction and a lighter fraction, and said heavy fraction is sent to coking step b) to be cracked with the tire fragments. This embodiment is particularly suitable for delayed-coking coking units. This fractionation is typically carried out in the same fractionation section as that carrying out fractionation step c).

[0011] The process according to the invention thus makes it possible to manufacture hydrocarbon fluids (liquid hydrocarbon fraction) using, in part, recycled feedstocks. Furthermore, the volume of hydrocarbon fluids produced, and in particular light hydrocarbon fluids, is increased by the incorporation of tire fragments. Due to their high aromatic content, tires are likely to form coke, which can then be used, for example, in the manufacture of tires.

[0012] By incorporating the recycled feed at the coking stage of an existing refinery unit, the process according to the invention allows less dilution of the recycled feed in the fossil feed compared to an introduction further upstream in the refinery, for example at the atmospheric distillation of crude oil.

[0013] Furthermore, by directly incorporating tire fragments, rather than tire oil, into the coking stage, the energy that would have been required to produce the tire oil and heat it before it entered the coking unit is saved. In the present invention, it is not necessary to heat the tire fragments before introducing them into the thermal cracking zone. This also avoids the need to heat tire oil, which can form gums and clog the heating system and / or the reactor due to the presence of dienes.

[0014] Finally, the hydrocarbon fractions of the effluent exiting step c) usually contain sulfur, nitrogen, metal, or other pollutants that must be removed in subsequent treatments. Tires also contain compounds containing nitrogen, sulfur, and metals. By submitting them to step b) at the same time as the fossil-based feedstock to be treated, it is possible to introduce hydrocarbons from the tires into each fossil fraction and send them to the usual subsequent treatments of fossil hydrocarbon fluids, where they will be freed of their impurities.

[0015] Step b) of coking can be implemented with a ratio of tire fragments / heavy hydrocarbon filler of fossil origin, or tire fragments / fraction of heavy hydrocarbon filler of fossil origin, of 0.1 to 50% by mass.

[0016] Step b) of coking can be implemented under one or more of the following conditions:

[0017] - a temperature of 400 to 650 °C, - a pressure of 0 to 20 bar gauge.

[0018] Step a) of supply may include:

[0019] - at least one tire fragmentation step, - at least one optional pretreatment step for tire fragments.

[0020] The tire fragments used in the present invention can have dimensions from 10 µm to 10 cm, preferably from 0.5 mm to 10 cm, more preferably from 1 mm to 5 cm, preferably from 2 mm to 2 cm.

[0021] The process may further include at least one step d) of treating at least one liquid hydrocarbon fraction of step c), optionally of each hydrocarbon fraction of step c), selected from a hydrotreating step, a hydrocracking step and a fluid catalytic cracking step, to produce an effluent having a reduced content of heteroelements (including metals) and / or olefins and / or dienes and / or aromatics, and / or more cracked.

[0022] The treatment in step d) can implement at least one reaction selected from hydrodesulfurization, hydrodeazotation, hydrodemetallation, hydrodearomatization, hydrodehalogenation, catalytic hydrogenation, hydrodeoxygenation, decarboxylation, decarbonylation, hydrocracking and fluid catalytic cracking.

[0023] Said heavy hydrocarbon filler of fossil origin used in the present invention can be chosen from a residue or a mixture of residues.

[0024] In one embodiment, the process according to the invention comprises only steps a) to c), and optionally one or more of the other steps previously described. Detailed description of the invention

[0025] The terms "including" and "includes" as used herein are synonymous with "including", "includes" or "contains", "containing", and are inclusive or boundless and do not exclude additional features, elements or unspecified method steps.

[0026] The expressions % by weight and % by mass have an equivalent meaning and refer to the proportion of the mass of a product relative to 100g of a composition comprising it.

[0027] Unless otherwise indicated, measurements given in parts per million (ppm) are expressed in mass.

[0028] Boiling points as mentioned herein are measured at atmospheric pressure, unless otherwise specified. An initial boiling point is defined as the temperature at which the first vapor bubble forms. A final boiling point is the highest temperature attainable during distillation. At this temperature, no more vapor can be transported to a condenser. The determination of the initial and final boiling points relies on techniques known in the trade, and several methods adapted according to the distillation temperature range are applicable, for example, NF EN 15199-1 (version 2020) or ASTM D2887 for measuring the boiling points of petroleum fractions by gas chromatography, ASTM D7169 for heavy hydrocarbons, and ASTM D7500, D86, or DI 160 for distillates.

[0029] The term "hydrocarbon" refers to both alkanes (saturated hydrocarbons), cycloalkanes, aromatics and unsaturated hydrocarbons.

[0030] By "heteroatom" is meant any element of an organic compound other than carbon and hydrogen.

[0031] The concentration of heteroatoms in the hydrocarbon matrix can be determined by any method known in the art. In particular, relevant characterization methods include X-ray fluorescence (XRF), inductively coupled plasma mass spectrometry (ICP-MS), and inductively coupled plasma atomic emission spectrometry (ICP-AES). Analytical scientists are able to identify the most suitable method for measuring each metal and, more generally, each heteroatom, depending on the hydrocarbon matrix considered. The oxygen content can be measured according to ASTM D5622-17 / D2504-88 (2015). The nitrogen content can be measured according to ASTM D4629-17. The sulfur content can be measured according to ISO 20846:2011. The halogen content, including chlorine, bromine, fluorine, can be measured according to the standard: ASTM D7359-18.

[0032] The aromatic content can be measured by gas chromatography, for example by a GCxGC or GC method, or by liquid chromatography, or by proton NMR and / or carbon NMR.

[0033] In the following description, the different embodiments described, and in particular the preferred embodiments of each step, can be combined according to the objective sought.

[0034] Heavy hydrocarbon charge of fossil origin

[0035] The heavy hydrocarbon filler of fossil origin used in the present invention is typically a residue or a mixture of residues.

[0036] The heavy hydrocarbon feedstock of fossil origin used in the present invention typically has one or more of the following characteristics:

[0037] - a sulfur content of at least 1.5% by mass, for example from 1.5 to 10% by mass,

[0038] - a metal content of 1 to 5000 ppm,

[0039] - a Conradson carbon content of at least 2% by mass, preferably of at minus 10% by mass, preferably more of at least 15% by mass, and potentially up to 40% by mass,

[0040] - an initial boiling point of 230 °C to 550 °C, preferably of at least 400 °C, preferably more than at least 440 °C, even more preferably at least 500 °C, preferably at least 525 °C,

[0041] - a final boiling point of 700 to 950 °C, preferably 700 to 900 °C, preferably from 700 to 850 °C.

[0042] By "fossil fuel" is understood a fuel which does not contain a component of biological origin, for example from biomass.

[0043] A hydrocarbon feedstock of fossil origin usable in the process may advantageously be selected from residues from the distillation of crude oil, in particular an atmospheric residue, a vacuum residue from the atmospheric distillation of crude oil, or from any other residue from fractionation sections of other units of the refinery and possibly treated, such as a heavy hydrocracking residue (commonly called "bleed"), a deasphalting pitch, or other.

[0044] Atmospheric residues (noted RAT) and vacuum residues (noted RSV) are respectively the column bottoms from the atmospheric distillation of crude oil, and from the vacuum distillation of an RAT.

[0045] Step a) of supplying tire fragments

[0046] The tires used in the present invention can be any type of existing tire: tires for motor vehicles, trucks, airplanes, two wheels (motorized or not), construction equipment, trams, subways, wheelbarrow tires,.....

[0047] Tires usually comprise natural rubber, synthetic rubber, and, depending on their complexity, textile and / or metallic cables or wires, possibly in the form of plies.

[0048] The tire is generally initially shredded to obtain either tire shreds still containing some of the textile fibers and / or metal wires contained in the tire (typically pieces of 10 cm) or granules (generally smaller than 5 mm) generally free of textile fibers or metal wires. The tire's polymer material can also be reduced to powder, in particular to micronized powder (for example, from 10 µm to 400 µm).

[0049] The tire fragments thus contain, or are made up of, natural rubber and / or synthetic rubber, and possibly textile and / or metal and / or other additives.

[0050] The fragments used in the present invention, in the form of powder, granules, or ground material, can thus have dimensions ranging from 10 µm to 10 cm, for example, from 10 µm to 0.5 mm for powder, from 0.5 mm to 5 mm for granules, and from 5 mm to 10 cm or from 5 mm to 2 cm for ground material. Sizes from 0.5 mm to 10 cm, preferably from 1 mm to 5 cm, and even more preferably from 2 mm to 2 cm, may advantageously be preferred.

[0051] In one embodiment, the fragments are granules, having a size of 0.5 to 4 mm, typically close to 2 mm, free from textile fibers and / or metallic threads.

[0052] Step a) of supply may include:

[0053] - at least one tire fragmentation step, - at least one optional preprocessing step for the fragments.

[0054] Step a) may also include a preliminary step of extracting a steel ring present in the tire (particularly in truck tires).

[0055] The fragmentation step can be implemented by any existing suitable means, by cutting, shredding and / or grinding, followed or not by sieving.

[0056] Several of the aforementioned steps may be implemented continuously or not. For example, at least one first step of cutting the tires into pieces may be provided, followed by at least one second step of reducing the particle size of the pieces to obtain fragments of the desired particle size.

[0057] One or more pretreatment steps may be provided to eliminate metals and / or textile fibers present in the fragments.

[0058] Metal removal can be implemented during the fragmentation stage, for example by magnetic separation, either during cutting, shredding and / or grinding, or between cutting, shredding and / or grinding operations.

[0059] In particular, one or more optical separation, grinding, chopping, screening, magnetic and / or eddy separation, centrifugation, density separation operations may be implemented.

[0060] It will thus be possible to provide for one or more processing steps between one or more fragmentation steps.

[0061] Step b) of coking

[0062] This step makes it possible to obtain an effluent that is at least partially cracked, namely an effluent consisting of the feed to be treated that is at least partially cracked.

[0063] According to the invention, this step is implemented in the presence of tire fragments supplied by step a) previously described.

[0064] Step b) of coking can be implemented with a ratio of tire fragments / heavy hydrocarbon load of fossil origin (or tire fragments / fraction of heavy hydrocarbon load of fossil origin) of 0.1 to 50% by mass, preferably 1 to 40% by mass, more preferably 1 to 30% by mass, or even 1 to 15% by mass.

[0065] Tire fragments can be introduced into the coking unit mixed with the heavy hydrocarbon feedstock of fossil origin, or with a fraction of this feedstock, or separately. The tire fragments are typically introduced at a cracking section of the coking unit or at a heating zone of the feedstock immediately before it enters the cracking section.

[0066] Coking is a reaction well known to those skilled in the art. It is a thermal cracking reaction carried out under severe conditions.

[0067] Typical coking conditions include a temperature of 400 to 600 °C, a pressure of 0 to 30 bar gauge, preferably 1 to 20 bar gauge, more preferably 1 to 15 bar gauge.

[0068] Coking produces a vaporized effluent and a solid residue (coke).

[0069] The vaporized effluent can be separated into gaseous hydrocarbons and non-condensable gases, naphtha and distillate(s) during step c) of fractionation.

[0070] The solid residue, here coke, can be sent to a carbon black production unit for the manufacture of tires, and / or to an activated carbon production unit for the manufacture of catalyst and / or adsorbent, or other.

[0071] The coking step can be implemented in a coking unit according to a delayed coking process or a fluid coking process.

[0072] Regardless of the process used, the tire fragments are preferably heated in the same enclosure as the fossil-based hydrocarbon feedstock or a fraction thereof, either in a furnace located upstream, particularly immediately upstream, of the cracking section, or within the cracking section itself. This cracking section may consist of one or more reactors, particularly fluidized bed reactors, or coke drums.

[0073] The delayed coking process consists of heating the feedstock to be treated to the thermal cracking temperature in a furnace before introducing it into coke drums in which the cracking reactions take place. In these drums, long-chain hydrocarbon molecules are cracked into an effluent consisting of hydrocarbon vapors containing essentially diesel fuel and lighter components, and solid coke. The solid coke remains in the drum at The coke drum fills in 16 to 24 hours. Once the drum is full of solid coke, the process switches to a second drum. While the second drum is filling with solid coke, the top and bottom heads of the first drum are removed, and the solid coke is extracted, for example, using a high-pressure water jet. Before being heated in a furnace and fed into the coke drums, the feedstock is fractionated into a heavy fraction, which is sent to the furnace and then to the coke drums. The remaining gases are recondensed and returned to fractionation along with the incoming feedstock. This fractionation is usually carried out in the same fractionation section as the one to which the effluents from the coke drums are sent. In this case, it is a heavy fraction of the fossil-based hydrocarbon feedstock that is cracked in the presence of the tire fragments.

[0074] In the case of implementation in a delayed coking unit, the tire fragments are introduced either into the oven or directly into the coke drums. They are thus not introduced at the fossil fuel feed fractionation section.

[0075] Step b) of coking can thus be preceded by a step of fractionating the feedstock to be treated, namely heavy hydrocarbon feedstock of fossil origin alone (without tire fragments), into a heavy fraction and a lighter fraction, the heavy fraction then being sent to step b) of coking. Those skilled in the art will know how to choose the point of separation between the heavy fraction returned to the coking step and the lighter fraction in the usual way under the conditions of implementation of the coking step.

[0076] The fluid bed process consists of bringing the feed to be treated into contact with a fluidized bed containing hot particles, generally coke particles. This produces an effluent consisting of hydrocarbon vapor and coke, the latter being deposited on the particles. The particles on which the coke is deposited can then be regenerated by combustion, and some of the coke particles can then be returned to the coking zone, for example, a fluidized bed reactor. In this case, the entire fossil-based hydrocarbon feedstock is cracked in the presence of the tire fragments in the cracking section.

[0077] Step c) of splitting

[0078] During this step, the effluent from step b) is separated into at least one liquid hydrocarbon fraction, and optionally at least one gaseous fraction.

[0079] The fractionation step is preferably implemented on the effluent directly from step b) of thermal cracking, without an intermediate step.

[0080] When step b) is implemented in a delayed coking unit, this fractionation step further receives the heavy hydrocarbon feed of fossil origin before the implementation of step b), as previously described.

[0081] The nature and number of hydrocarbon fractions separated during step c) depends on the conditions of the reaction carried out in step b).

[0082] In one embodiment, the effluent from step b) is fractionated into at least one liquid hydrocarbon fraction selected from a naphtha fraction, a kerosene fraction, a diesel fraction, a vacuum diesel fraction, and a residue.

[0083] According to the process, this fractionation can be carried out by adding a separation column, for example a distillation column, atmospheric or under reduced pressure, or by lateral withdrawal.

[0084] This fractionation typically allows the effluent from step b) to be separated into naphtha (typically with a final boiling point of about 170 °C), light diesel (typically distilling in the range of 170-370 °C), heavy diesel (typically distilling in the range of 370-525 °C), and residue (typically having an initial boiling point of 520 °C to 540 °C).

[0085] Typically, fractionation is carried out under the usual fractionation conditions following a coking or viscoreduction step.

[0086] The fractionation step can in particular be carried out under atmospheric pressure or under reduced pressure, for example at an absolute pressure of 0.1 mbar to 500 mbar, preferably from 0.1 mbar to 100 mb, more preferably from 0.5 to 10 mbar.

[0087] Processing step d)

[0088] The at least one liquid hydrocarbon fraction separated in step c) generally contains impurities containing heteroatoms and / or dienes and / or olefins, and / or aromatics, and / or relatively long hydrocarbon chains.

[0089] These heteroatoms can be nitrogen, sulfur, oxygen, silicon, halogens, and / or metals.

[0090] Step d) of treatment makes it possible to reduce the content of heteroatoms and / or dienes and / or olefins and / or aromatics, and / or to further crack at least one liquid hydrocarbon fraction separated in step c).

[0091] Step d) can implement one or more of the following reactions: hydrodesulfurization, hydrodeazotation, hydrodemetallation, hydrodearomatization, hydrodehalogenation, catalytic hydrogenation, hydrodeoxygenation, decarboxylation, decarbonylation, hydrocracking, fluid catalytic cracking.

[0092] Depending on the reactions implemented, step d) can be carried out in the presence of dihydrogen and at least one catalyst under suitable usual conditions.

[0093] Depending on the objective sought, a liquid hydrocarbon fraction separated in step c) may be sent to a hydrotreating unit and / or a hydrocracking unit to remove one or more of the specific impurities, and / or to a dedicated fluid catalytic cracking (FCC) unit for further cracking, alone or mixed with one or more other liquid hydrocarbon fractions separated in step c), or with other refinery effluents.

[0094] Advantageously, step d) of hydrotreating and / or hydrocracking and / or fluid catalytic cracking can thus be implemented in one or more existing hydrotreating units and / or hydrocracking units and / or fluid catalytic cracking units of a refinery, usually used to treat feedstocks of fossil origin, and in particular specific fractions thereof.

[0095] The present invention can therefore be implemented in an existing refinery, without having to modify it. Detailed description of the figures

[0096] Other features and advantages of the invention will become apparent from the following description of a particular embodiment of the invention, given by way of example but not limitation, with reference to the attached drawing in which:

[0097] The [Fig. 1] schematically represents a first possible embodiment of the invention.

[0098] Fig. 2 schematically represents a second possible embodiment of the invention.

[0099] In the figures, identical elements are designated by the same reference numerals.

[0100] In one possible embodiment of [Fig. 1], a heavy hydrocarbon feedstock of fossil origin of the type previously described (1) is at least partially cracked in a Cunit coking unit. The coking unit is suitable for carrying out step b) of the process. Any type of unit commonly used for the type of reaction envisaged may be used. ...

[0101] According to the invention, tire fragments (10), in the form of powder, granules or ground, are sent into the Cunit coking unit, mixed with the heavy hydrocarbon feedstock of fossil origin (1) or separately.

[0102] The effluent (2) exiting the coking unit is then fractionated, in particular directly, without an intermediate step, in a Funit fractionation unit, capable of implementing step c), to be fractionated there into at least one liquid hydrocarbon fraction.

[0103] In the example shown, the effluent (2) is fractionated into a gaseous fraction (3), and here into four liquid hydrocarbon fractions, for example into a naphtha fraction (4), a light diesel fraction (5), a heavy diesel fraction (6), and a residue (7). Of course, the invention is not limited by the number and nature of the fractions separated, which will be chosen by those skilled in the art according to the coking conditions implemented. Depending on the conditions of the coking reaction, the fractionation unit may be integrated into the coking unit (for example, including one or more lateral draw-offs) or be a separate unit, in particular a splitting column.

[0104] Depending on the nature of any impurities present, a separated hydrocarbon liquid fraction may be sent to a hydrotreating unit and / or a hydrocracking unit and / or a fluid catalytic cracking (FCC) unit, either alone or mixed with at least one other separated hydrocarbon liquid fraction, or with another refinery effluent. One or more hydrotreating and / or hydrocracking and / or fluid catalytic cracking units may thus be provided, each dedicated to one or more separated hydrocarbon liquid fractions. In the example, three separate hydrotreating units, HDTi, HDT2, and HDT3, are planned, treating fractions (4), (5), and (6) separately, respectively, and a hydrocracking unit (HCKi) or a fluid catalytic cracking unit (FCCi) is planned to treat residue (7).Each unit can then be operated to remove one or more specific impurities by one or more reactions chosen from hydrodesulfurization, hydrodeazotation, hydrodemetallation, hydrodearomatization, hydrodehalogenation, catalytic hydrogenation, hydrodeoxygenation, decarboxylation, decarbonylation, hydrocracking, and / or be operated to carry out additional cracking by fluid catalytic cracking and / or hydrocracking.

[0105] The invention is not, however, limited to the number of hydrotreating and / or hydrocracking and / or fluid catalytic cracking units, nor to the nature of the reactions they employ. A person skilled in the art will be able to determine which treatment is necessary to remove one or more specific impurities from a given feedstock, or even to carry out other reactions, depending on the objective sought.

[0106] During the implementation of step b), a solid residue (11) is produced as previously described. The solid residue (coke) can optionally be reused for the manufacture of tires, adsorbents and / or catalysts.

[0107] The embodiment shown [Fig. 1] can in particular be implemented with a coking unit comprising a fluidized bed reactor.

[0108] Figure 2 represents another possible embodiment of the process according to the invention implemented in a CRunit delayed coking unit.

[0109] The feed (1) is first sent into the Funit fractionation unit. The feed (1) generally enters the lower part of the Funit fractionation unit, below the effluent inlet (2).

[0110] The heaviest fraction (residue) (7) separated in this fractionation unit Funit is sent to the delayed coking unit CRunit, typically to one of the two coke drums which this type of unit usually includes, in which it undergoes thermal cracking.

[0111] The effluent (2) exiting the coke drums is sent to the Funit fractionation unit. The Funit fractionation unit allows the separation of the heaviest fraction (7) sent to the CRunit delayed coking unit, a heavy gas oil (6), a light gas oil (5), a coker naphtha (4) and gases (3).

[0112] In the embodiment shown, the entirety of the heaviest fraction (7) is sent to the CRunit delayed coking unit. However, the invention is not limited to this embodiment, and a portion of the heaviest fraction (7) could be sent to the delayed coking unit, with the remainder being sent to an HCKi hydrocracking unit and / or an FCCi fluid catalytic cracking unit (not shown).

[0113] According to the invention, the tire fragments (10), in the form of powder, granules or ground-up, are introduced into the CRunit delayed coking unit.

[0114] As explained above, the coke drums operate alternately: the coke from one drum is discharged while thermal cracking is in progress in the other drum. Water is typically used to discharge the coke from the coke drums. The coke can then be used to produce carbon black and / or activated carbon.

Claims

Demands

1. A process for manufacturing hydrocarbon fluids from a heavy hydrocarbon feedstock of fossil origin and tire fragments, the process comprising: a) a step of supplying tire fragments, b) a coking step carried out in a coking unit during which said heavy hydrocarbon feedstock of fossil origin, or a fraction thereof, undergoes thermal cracking under coking conditions in the presence of the tire fragments supplied by step a), and at least partially cracked effluent and solid residue are produced, c) a fractionation step in which the effluent from step b) is fractionated into at least one liquid hydrocarbon fraction.

2. A manufacturing process according to claim 1, wherein the coking step b) is carried out with a ratio of tire fragments / heavy fossil fuel filler, or tire fragments / fraction of heavy fossil fuel filler, of 0.1 to 50% by mass.

3. A manufacturing process according to any one of claims 1 or 2, wherein the coking step b) is carried out under one or more of the following conditions: - a temperature of 400 to 650 °C, - a pressure of 0 to 20 gauge bars.

4. A manufacturing process according to any one of claims 1 to 3, wherein, prior to step b), said heavy hydrocarbon feedstock of fossil origin is fractionated into a heavy fraction and a fraction lighter than the heavy fraction, and said heavy fraction is sent to the coking step b) to be cracked there with the tire fragments.

5. A manufacturing process according to any one of claims 1 to 4, wherein the supply step a) comprises: - at least one tire fragmentation step, - at least one optional tire fragment pretreatment step.

6. A manufacturing method according to any one of claims 1 to 5, wherein the tire fragments have dimensions from 10 pm to 10 cm, preferably from 0.5 mm to 10 cm, preferably more from 1 mm to 5 cm, preferably from 2 mm to 2 cm.

7. A manufacturing process according to any one of claims 1 to 6, further comprising: d) at least one treatment step of at least one liquid hydrocarbon fraction of step c), selected from a hydrotreating step, a hydrocracking step and a fluid catalytic cracking step, producing a treated effluent having a reduced content of heteroelements and / or olefins and / or dienes and / or aromatics, and / or further cracked.

8. A manufacturing process according to claim 7, wherein the treatment step implements at least one reaction selected from hydrodesulfurization, hydrodeazotation, hydrodemetallation, hydrodearomatization, hydrodehalogenation, catalytic hydrogenation, hydrodeoxygenation, decarboxylation, decarbonylation, hydrocracking and fluid catalytic cracking.

9. A manufacturing process according to any one of claims 1 to 8, wherein said heavy hydrocarbon feedstock of fossil origin is a residue or a mixture of residues.

10. A manufacturing process according to any one of claims 1 to 9, wherein the solid residue produced during this step is then sent to a carbon black production unit for the manufacture of tires and / or to an activated carbon production unit for the manufacture of catalyst and / or adsorbent.

Images