OA19656A - Process for manufacturing materials in the form of granules which can be used as road binder or waterproofing binder and device for its manufacture. - Google Patents

Abstract

A method of manufacturing a material in divided form, solid at room temperature, usable as a road binder or as a sealing binder, such as a road bitumen, a pitch, a stock solution for a bitumen/polymer composition, a clear binder, this method comprising the implementation of a device (1) intended for granulation which comprises at least two coaxial drums (4A, 4B) and a horizontal tread (6): a fixed inner drum (4B) comprising at least one orifice (5B) and a rotating outer drum (4A) comprising a plurality of orifices (5A), this method comprising at least: (i) heating a first composition (2) to a temperature at which it is fluid, (ii) introducing the first composition (2) in the fluid state into the inner drum (4B) of the granulation device, (iii) distributing the first composition towards the outside in the form of drops (7) through the orifices (5A) of the rotating outer drum (4A), (iv) depositing the drops (7) on the tread (6), and (v) optionally, coating the drops (7) with the second composition. Device for manufacturing these materials.

Description

PROCESS FOR PRODUCING MATERIAL IN THE FORM OF

GRANULES USABLE AS ROAD BINDER OR SEALING BINDER

AND DEVICE FOR ITS MANUFACTURE

The present invention relates to a method for manufacturing a material in divided form, solid at room temperature, usable as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a mother solution for a bitumen/polymer composition, a clear binder. The material thus obtained has advantageous properties of resistance to compression and to fineness during its transport and/or its storage at room temperature. The method is economical and applicable on an industrial scale. The invention also relates to a device for the manufacture of these materials.

State of the prior art

Much work has been done on the production of improved shapes, easily handled, divided shapes, of materials used for road construction in order to facilitate their transportation and implementation. Another constraint in the formulation of these materials is to maintain their mechanical performance, in particular their resistance to high road stresses, their resistance to aging.

The vast majority of bitumen is used in construction, primarily for road paving, or in industry, such as roofing applications. It is typically a highly viscous black material that is solid at room temperature and becomes fluid upon heating.

Generally, bitumen is stored and transported hot, in bulk, in tanker trucks or by ship at high temperatures of around 120°C to 160°C. However, the storage and transport of hot bitumen has certain disadvantages. On the one hand, the transport of hot bitumen in liquid form is considered dangerous and is very regulated from a regulatory point of view. This mode of transport does not present any particular difficulties when the equipment and transport infrastructure are in good condition. Otherwise, it can become problematic: if the tanker truck is not sufficiently insulated, the viscosity of the bitumen may increase during a too long journey. Bitumen delivery distances are therefore limited. On the other hand, maintaining bitumen at high temperatures in tanks or tanker trucks consumes energy. Furthermore, maintaining bitumen at high temperatures for a long period of time can affect the properties of the bitumen and thus change the final performance of the mix.

To overcome the problems of transporting and storing hot bitumen, packaging has been developed that allows bitumen to be transported and stored at ambient temperature. This method of transporting bitumen in ambient temperature packaging represents only a small fraction of the quantities transported worldwide, but it meets very real needs in geographical regions that are difficult and expensive to access using traditional means of transport.

Examples of packaging include bitumen in the form of granules transported and/or stored in bags, often used in places where the ambient temperature is high. These granules have the advantage of being easy to handle.

The same difficulty is encountered with pitches and bituminous compositions comprising them, clear binders, bitumen/polymer compositions, in particular stock solutions of bitumen/polymer compositions.

US 3,026,568 describes a method for manufacturing bitumen granules coated with a powdery material, such as limestone powder. The bituminous material is extruded through a nozzle into an atomizing tower. This method can only be implemented with mineral powders and in quantities not compatible with industrial production. Another disadvantage is that the granules can only be coated by dusting.

Application WO2009/153324 describes bitumen granules produced by co-extrusion of a bitumen base and a polymeric anti-caking composition, in particular polyethylene.

US application 2011/0233105 describes asphalt that is solid at room temperature in the form of granules comprising a core and a coating layer, these granules being formed by extrusion through a die.

The disadvantage of the processes described above is the implementation of an extrusion step which is limiting from the point of view of yield to industrially produce road bitumen in divided and solid form at high ambient temperature at optimized costs. In addition, this process is expensive and only allows low production rates.

Document FR 2 998 896 describes a process for producing granules of bituminous composition. The granules are formed by shear cutting. This process has the disadvantage of not being able to be applied under economically satisfactory conditions to large quantities of materials.

Document US 4,279,579 discloses an extrusion device for producing granules from a molten mass of material. However, this document does not describe any specific use of this equipment for the production of granules of materials usable as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a stock solution for a bitumen/polymer composition, a clear binder. When such a device is used with a composition of this type, it has been observed that depending on the structural and operating parameters of this device, granules or an agglomerated mass of particles can be obtained.

Document US 2011/0185631 discloses a device and a method for preparing asphaltene-rich pellets by extrusion in the form of drops of molten heavy hydrocarbons and then by quenching the drops formed in a cooling medium.

Document EP 0 511 197 discloses an apparatus for extruding a fluid mass onto a mobile support. This apparatus comprises in particular a first fixed cylinder and a second cylinder arranged around the first cylinder and capable of rotating around the first cylinder, the fluid mass placed in the first cylinder is extruded through nozzles on the surface of the second cylinder.

Document WO 2016/110747 describes a method for packaging bitumen in the form of pellets, characterized in that the bitumen is heated and then flowed through a perforated rotating cylinder so as to form droplets of hot bitumen which are then cooled on a tread maintained at a temperature of 8°C to 10°C.

Document FR 2 765 229 discloses clear binders and bituminous binders which can be put in the form of pellets or granules.

The Applicant therefore sought to develop a process for manufacturing granules of materials that can be used as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a stock solution for a bitumen/polymer composition, a clear binder, in particular bitumen granules, capable of being subjected to high ambient temperatures without creeping, in particular materials, in particular bitumens, in the form of granules whose adhesion and agglomeration during their transport and/or storage and/or handling at high ambient temperature is reduced compared to the granules of the prior art. It was sought to develop a process that can be extrapolated to large quantities of material, which is economical, reproducible and which can be implemented without difficulty on an industrial scale.

An objective of the present invention is to provide a material which can be used as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a mother solution for a bitumen/polymer composition, a clear binder, in particular a road bitumen, which can be transported and/or stored and/or handled at high ambient temperature, and whose properties are retained over time.

In particular, the aim of the present invention is to provide a material which can be used as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a mother solution for a bitumen/polymer composition, in particular a road bitumen, which can be transported and/or stored for a period of more than 2 months, preferably 3 months, and at high ambient temperature, in particular at a temperature below 100°C, preferably from 20°C to 80°C.

Another objective of the invention is to provide a material which can be used as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a mother solution for a bitumen/polymer composition, a clear binder, in particular a road bitumen, which is easy to handle, in particular at high ambient temperature, in particular at a temperature of up to 100°C, preferably from 20°C to 80°C.

In particular, the aim of the present invention is to provide a material which can be used as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a stock solution for a bitumen/polymer composition, a clear binder, in particular a road bitumen, which can be easily handled after a prolonged transport and/or storage period at high ambient temperature, in particular during a transport and/or storage period of more than 2 months, preferably more than 3 months, and at a temperature of up to 100°C, preferably between 20°C and 80°C.

An objective of the present invention is to provide a material usable as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a stock solution for a bitumen/polymer composition, a clear binder, in particular a road bitumen, in a form which allows it to flow in solid form at room temperature, so as to be able to handle it without loss of material. It has been sought to provide a material usable as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a stock solution for a bitumen/polymer composition, a clear binder, in particular a road bitumen, which is in a form which allows it to be packaged in a container, to be unpacked, to be transferred into equipment, even at a high room temperature, without the need to heat it, and without loss of material. The material usable as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a mother solution for bitumen/polymer composition, in particular the proposed bitumen, is in divided form and solid at room temperature so that it can satisfactorily resolve the problems mentioned above.

Another objective is to propose an industrial and economical process for manufacturing a material that can be used as a road binder or as a waterproofing binder, such as road bitumen, pitch, a mother solution for bitumen/polymer composition, a clear binder, in particular road bitumen, transportable and/or storable at room temperature.

Another objective of the invention is to propose an industrial and economical process for manufacturing coatings from road bitumen that can be transported and/or stored at room temperature.

Another objective of the invention is to propose an ecological and economical method for transporting and/or storing and/or handling a material usable as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a mother solution for a bitumen/polymer composition, a clear binder, in particular a road bitumen, at ambient temperature, making it possible to avoid the use of additional means for maintaining the temperature of said material during transport and/or storage and/or handling and making it possible to minimize the presence of waste and/or residues.

Summary of the invention

The invention relates to a method for manufacturing a material that can be used as a road binder or as a waterproofing binder, solid at room temperature in the form of granules comprising a core based on a first composition and optionally a coating layer based on a second composition, the first composition comprising at least one material chosen from: a bitumen base, a pitch, a clear binder, this method comprising the use of a device intended for granulation which comprises at least two coaxial drums and a horizontal tread: a fixed inner drum comprising at least one orifice and a rotating outer drum comprising a plurality of orifices, the drums being placed above one end of the horizontal tread, driven at a speed Vr, this method comprising at least:

(i) heating the first composition to a temperature at which it is fluid, (ii) introducing the first composition in the fluid state into the inner drum of the granulating device, (iii) dispensing the first composition outwardly, in the form of drops through the orifices of the outer rotating drum, (iv) depositing the drops on the tread, and (v) optionally, coating the drops with the second composition.

According to a preferred embodiment, the method further comprises, after step (iv) between steps (iv) and (v), a step (iv') of cooling the drops of the first composition.

According to a preferred embodiment, the cooling (iv') is carried out by means of a temperature gradient on the tread.

According to a further preferred embodiment, the tread is conditioned at different temperatures over several sections (SI), ...(Si) of its path, with i an integer ranging from 2 to 8, preferably from 2 to 4 by thermal conditioning means.

According to a preferred embodiment, the tread is conditioned at room temperature over a first section (SI) of its path, and at a temperature less than or equal to 20°C, preferably less than or equal to 15°C, over a second section S2.

According to a further preferred embodiment, the ratio of the length of the first section (S1) to the length of the second section (S2) ranges from 25/75 to 75/25.

According to a preferred embodiment, the rotating outer drum of the device comprises orifices with a diameter ranging from 2 to 10 mm, preferably from 2 to 8 mm, preferably from 3 to 7 mm, even better from 3.5 to 6 mm.

According to a preferred embodiment, in step (i) the first composition is brought to a temperature ranging from 100 to 270°C, preferably from 100 to 180°C, preferably from 120 to 160°C, even better from 130 to 150°C.

According to a preferred embodiment, the speed V _R of the tread is less than 4 m/min.

According to a preferred embodiment, the method further comprises, after step (v), at least one step (vi) of drying the coated granules, preferably at a temperature ranging from 20 to 60°C, for a period ranging from 5 minutes to 5 hours, preferably from 5 minutes to 2 hours.

According to a preferred embodiment, the material usable as a road binder or as a waterproofing binder is chosen from: a bitumen composition, a pitch, a clear binder, a bitumen/polymer stock solution, a clear binder/polymer stock solution.

According to a preferred embodiment, the first composition comprises at least one material chosen from: a bitumen base, a pitch, a clear binder, a bitumen/polymer composition, a clear binder/polymer composition, a bitumen/polymer stock solution; a clear binder/polymer stock solution; a mixture of these materials.

According to a preferred embodiment, the second composition comprises at least one anti-caking compound.

According to a preferred embodiment, the anti-caking compound is chosen from: talc; fines generally with a diameter of less than 125 μm, such as siliceous fines, with the exception of calcareous fines; sand such as Fontainebleau sand; cement; carbon; wood residues such as lignin, lignosulfonate, conifer needle powders, conifer cone powders, in particular pine; rice husk ash; glass powder; clays such as kaolin, bentonite, vermiculite; alumina such as alumina hydrates; silica; silica derivatives such as silica fumes, functionalized silica fumes, in particular hydrophobic or hydrophilic silica fumes, fumed silicas, in particular hydrophobic or hydrophilic fumed silicas, silicates, silicon hydroxides and silicon oxides; plastic powder; lime; plaster; rubber crumb; polymer powder, such as styrenebutadiene (SB) copolymers, styrene-butadiene-styrene (SBS) copolymers and mixtures of these materials.

According to a preferred embodiment, the second composition comprises at least 10% by mass of one or more viscosifying compounds relative to the total mass of the second composition.

According to a preferred embodiment, the viscosifying compound has a dynamic viscosity greater than or equal to 50 mPa.s' ¹ , preferably from 50 mPa.s' ¹ to 550 mPa.s' ¹ , more preferably from 80 mPa.s' ¹ to 450 mPa.s' ¹ , the viscosity being a Brookfield viscosity measured at 65°C.

According to a further preferred embodiment, the viscosifying compound is chosen from:

- gelling compounds, preferably of plant or animal origin, such as gelatin, agar-agar, alginates, cellulose derivatives, starches, modified starches and gellan gums;

- polyethylene glycols (PEG) such as PEGs having a molecular weight between 800 g.iuof ¹ and 8000 g.mof ¹ ;

- mixtures of such compounds.

According to a preferred embodiment, the second composition comprises from 10 to 90% by mass of one or more anti-caking compounds relative to the total mass of the second composition, preferably from 15 to 90% by mass, and from 10 to 90% by mass of at least one viscosifying compound relative to the total mass of the second composition, preferably from 10 to 85% by mass.

According to a preferred embodiment, the second composition consists essentially of one or more anti-caking compounds.

According to a preferred embodiment, the bitumen base has a needle penetrability measured at 25°C according to standard EN 1426 of 5 to 330 1/10 mm, preferably of 20 to 220 1/10 mm.

According to a preferred embodiment, the first composition further comprises at least one chemical additive chosen from: an organic compound, a paraffin, a polyphosphoric acid and their mixtures.

According to a preferred embodiment, the first composition comprises:

- 30 to 40% of at least one polymer,

- from 4 to 6% of at least one compatibilizing agent, from 3% to 15% of at least one anti-caking agent, the percentages being by mass relative to the total mass of the first composition.

According to a preferred embodiment, the first composition has a ring and ball softening temperature (RBT) greater than or equal to 90°C, the RBT being measured according to standard EN 1427.

According to a preferred embodiment, the first composition has a needle penetrability measured at 25°C according to standard EN 1426 of 5 to 45 1/10mm.

The invention also relates to the use of the method as described above and below in detail, for manufacturing a composition of material usable as a road binder or as a coating binder, solid at room temperature, which has stability during transport and storage at a temperature ranging from 20 to 80°C for a period greater than or equal to 2 months, preferably greater than or equal to 3 months.

The invention further relates to a device usable for implementing a method as described above and below in detail, which comprises at least: a first cylindrical drum arranged above the tread and capable of rotation about a longitudinal axis, said first drum comprising a plurality of first passages through the periphery of the drum, a second cylindrical drum coaxial with the first drum, comprising means for longitudinally admitting into said second drum the mass to be extruded and comprising on a part of its wall a plurality of second passages directed towards the tread and radially aligned with said first passages, said wall part being arranged adjacent to said first drum, said first drum being mounted to allow its continuous rotation through 360° about the longitudinal axis relative to said second drum such that the relative rotation between said drums sequentially produces a misalignment and an alignment of the first passages and second passages to allow the fluid mass to move radially outwards through the aligned passages, and on the tread, this device further comprising:

- a tank equipped with heating means and stirring means,

- an injection channel, or several injection channels, allowing the transfer of the composition contained in the reservoir to the interior of the second drum through the admission means, this device being characterized in that it comprises:

- a tank into which an additive composition can be introduced, the tank being connected to the injection channel via an injector and allowing injection of the additive composition into the bitumen composition at the injection channel, located downstream of the tank and upstream of the double drum.

Figures

Figure 1: schematic representation of a device 1 according to the invention

Figure 2: Sectional view of part of the operation of the double drum 4 in the device 1 of the invention

Figure 3: schematic perspective representation of the reservoirs and means for injecting materials into a device 1 according to the invention

Detailed description

The objectives that the applicant set for itself were achieved by shaping drops of compositions of material usable as a road binder or as a waterproofing binder, such as a road bitumen, a pitch, a mother solution for a bitumen/polymer composition, a clear binder, in particular bitumen, by means of a particular granulation device, this device making it possible to form the core of the core/shell structures, under conditions which are reproducible, extrapolable on a large scale, economical and provide granules having improved properties compared to the granules of the same materials known from the prior art.

The expression "between X and Y" includes the limits. This expression therefore means that the interval in question includes the values X, Y and all the values from X to Y.

“Ambient temperature” means the temperature resulting from the climatic conditions in which the material usable as a road binder or as a waterproofing binder, in particular road bitumen, is transported and/or stored. More precisely, the ambient temperature is equivalent to the temperature reached during the transport and/or storage of the material usable as a road binder or as a waterproofing binder, in particular road bitumen, it being understood that the ambient temperature implies that no heat input is provided other than that resulting from the climatic conditions.

The invention relates to materials which can be used as road binder or as waterproofing binder, in particular bitumens which can be subjected to a high ambient temperature, in particular a temperature of up to 100°C, preferably from 20°C to 80°C.

By "material usable as a road binder or as a waterproofing binder" is meant, within the meaning of the present invention, any material capable of being used for this purpose, and in particular: bitumen bases, bitumen/polymer compositions, bitumen compositions with additives, pitches, bitumen-polymer stock solutions, clear binders, clear binder-polymer stock solutions, mixtures of these materials in all proportions.

A "material that is solid at room temperature" means a material that has a solid appearance at room temperature regardless of the transport and/or storage conditions. More specifically, a material that is solid at room temperature means a material that retains its solid appearance throughout transport and/or storage at room temperature, i.e. a material that does not thin at room temperature under its own weight and, furthermore, does not creep when subjected to pressure forces resulting from the transport and/or storage conditions.

Bitumen that is solid at room temperature means bitumen that has a solid appearance at room temperature regardless of the transport and/or storage conditions. More specifically, bitumen that is solid at room temperature means bitumen that retains its solid appearance throughout transport and/or storage at room temperature, i.e. bitumen that does not creep at room temperature under its own weight and, furthermore, does not creep when subjected to pressure forces resulting from transport and/or storage conditions.

By "coating layer covering all or part of the surface of the core" is meant that the coating layer covers at least 90% of the surface of the core, preferably at least 95% of the surface of the core, more preferably at least 99% of the surface of the core.

The expression “consists essentially of” followed by one or more characteristics means that, in addition to the components or steps explicitly listed, components or steps which do not significantly modify the properties and characteristics of the invention may be included in the process or material of the invention.

The method according to the invention makes it possible to obtain granules of material usable as a road binder or as a sealing binder, in particular solid bitumen, comprising a coating layer which is resistant to climatic conditions and to the conditions of transport and/or storage of road binders and/or sealing binders, in particular which is resistant to climatic conditions and to the conditions of transport and/or storage of solid road bitumen, which breaks easily under a mechanical shearing effect, such as for example under the effect of mechanical shear applied in a tank such as a mixer or a mixer drum during the production of asphalt.

More specifically, the coating layer withstands the transport and/or storage of road binders and/or waterproofing binders, particularly bitumen, at room temperature in “Big Bags” while being brittle under the effect of mechanical shear. It thus allows the release of the bitumen core during the production of asphalt mixes.

The process:

The method of the invention is carried out by means of a device which is shown in Figures 1 to 3 and which is illustrated by the production of a bitumen composition. However, the method could be carried out, with simple adaptations of the parameters, to other compositions such as pitches, clear binders, stock solutions or mixtures of such compositions in any proportions.

Part of the device as described in Figure 1 is described in great detail in US Patent 4,279,579. Different models of this device are commercially available from the company Sandvik under the trade name Rotoform. This device 1 comprises a tank 11 equipped with heating means (not shown), and stirring means 13, making it possible to bring the container of the tank 11, a bitumen composition 2, to the fluid state. Depending on the additives possibly present in the bitumen base, the first composition 2 is brought to a temperature chosen to avoid degrading said additives. One or more injection channels 3 allow(s) the transfer of the fluid bitumen composition 2 inside the double pelletizing drum 4. As described in US patent 4,279,579, the injection of the bitumen composition 2 inside the double pelletizing drum 4 is done, as shown in FIG. 3, through intake means 17 placed at a lateral end 18 of the drum 4. In an innovative manner, the device of the invention further comprises a reservoir 14 in which an additive composition 15 is placed. This reservoir 14 is connected to the injection channel 3 through an injector 16 and allows an injection of the additive composition 15 into the bitumen composition 2 at the channel 3, located downstream of the reservoir 11 and upstream of the double drum 4. Indeed, certain additives degrade when they are stored hot in a bitumen composition 2. bitumen and their introduction into the tank 11 would lead to their destruction before the bitumen composition 2 has reached the double pelletizing drum 4. Other additives settle during storage and lead to the formation of an inhomogeneous composition. Also, the presence of an additive tank 14 equipped with an injector 16 opening into the injection channel 3 makes it possible to overcome these difficulties and to introduce into the pelletizing drum 4 a bitumen composition 2, of a composition sufficiently stable over time and sufficiently homogeneous to form the granules of the desired composition. The pelletizing drum 4 comprises a fixed internal drum or stator 4B equipped with heating means (not shown) making it possible to maintain the composition 2, possibly with additives, in a fluid state. It comprises a rotating external drum 4A, the two drums being equipped with slots, nozzles and orifices allowing the pelletization of drops of bitumen 7 through the first fixed drum and the orifices 5 of the rotating external drum. For example, as shown in Figure 2, the first fixed drum 4B may comprise a longitudinal slot 5B and the second rotating drum 4A comprises orifices 5A of substantially identical size, regularly aligned, as illustrated in US patent 4,279,579. Other arrangements of the orifices of the two drums are possible. Under the effect of the substantially homogeneous internal pressure inside the double drum 4 of the device 1, when the orifices 5B and 5A of the two drums are opposite each other, the drops 7 are pelletized regularly through said orifices 5 and thus have substantially homogeneous sizes. The drops of bitumen 7 are deposited on the upper face 6A of a horizontal tread 6, driven by the rollers 12A and 12B, and one end of which is placed under the double drum 4. The dimensions of the orifices 5 of the rotating external drum make it possible to control the size of the drops of bitumen 7. For example, the orifices 5A may consist of substantially circular orifices with a diameter of 4 mm. The tangential speed V _T of the double drum 4 is parallel to the tread 6 and in the same direction as the speed V _R of the tread 6. The speed V _R of the tread 6 is adapted to allow a regular deposition of the drops 7 and at a sufficient distance from each other to avoid agglomeration or coalescence of the drops 7. V _R and Vt are substantially identical. For example, a speed V _T = 3 m/minute gives satisfactory results. The tread 6 is equipped with a first thermal conditioning device 8 over a first section S1 of its length and a second thermal conditioning device 9 over a second section S2 of its length. The conditioning allows the gradual cooling and solidification of the bitumen drops 7. The thermal conditioning means may consist of nozzles 8, 9 for vaporizing a fluid, such as water, onto the lower face 6B of the tread 6, at a chosen temperature. For example, the section S1 over a length of 5 m conditions the tread 6 at ambient temperature (22-28°C), and the section S2, also over a length of 5 m, cools the tread to 20°C or 15°C. According to a variant, the tread 6 can be equipped with a greater number (for example 3, 4, 5, 6) of successive thermal conditioning devices so as to control the temperature of the tread 6, section by section, in a more precise manner. The tread 6 can have any suitable dimensions in order to allow the deposit and progressive cooling of the drops of bitumen 7. For example, the tread 6 can have a length of 10 m and a width of 60 cm. The dimensions of the tread 6 are adapted in particular according to the dimensions of the double drum 4 (width of the double drum 4 in particular), the quantities of material to be treated, the desired temperature gradient. At the end of the tread opposite the double drum 4, the drops of bitumen 7 are transferred to receiving means 10 which may consist for example of a storage device, such as "big bags", a coating device, or a second tread allowing their transfer to processing equipment such as equipment for coating the drops of bitumen 7. Preferably, the drops of bitumen 7 are transferred to a coating device (not shown) such as a coating device by dipping, by spraying or any other suitable device, depending on the coating composition chosen.

The bitumen drops 7 are prepared from a first composition comprising at least one material chosen from: a bitumen base, a pitch, a clear binder, their mixtures. Preferably, said first composition comprises at least one or more bitumen bases. The method of the invention may comprise, after the step of depositing the drops 7 on the tread 6 and before a possible coating step, a step (iv') of cooling the drops 7 of the first composition 2. This cooling may be done by any means known to those skilled in the art, such as storage at a low temperature, blowing cold air, etc.

The method of the invention further optionally comprises coating the drops with the second composition. This coating may optionally be followed by drying the coated granules at a temperature ranging from 20 to 60°C, for a period ranging from 5 minutes to 5 hours, preferably from 5 minutes to 2 hours.

Preferably, when implementing the method of the invention, the mass ratio of the coating composition (second composition) relative to the mass of the first composition comprising the bitumen base, optionally with additives, forming the core is from 0.1 to 1, advantageously from 0.2 to 0.9.

According to a first embodiment of the invention, the coating composition, or second composition, comprises one or more anti-caking compounds.

According to a second embodiment of the invention, the coating composition, or second composition, comprises at least one viscosifying compound and at least one anti-caking compound.

The viscosifying compound and the anti-caking compound are as described below.

These different coatings can be used regardless of the chemical nature of the first composition; they are particularly suitable for bitumen compositions. Where appropriate, the person skilled in the art knows how to adapt the second coating composition according to the nature of the first composition to produce an optimized result.

The granules:

According to the invention, the material usable as a road binder or as a waterproofing binder, in particular bitumen, solid at room temperature, is packaged in a divided form, that is to say in the form of small units, which are called granules or particles, comprising a core based on bitumen or pitch or clear binder, or a mixture of these components (first composition) and optionally an envelope or shell or coating or covering layer or covering (second composition).

Preferably, the granules of material usable as a road binder or as a waterproofing binder, in particular solid bitumen, according to the invention may have, within the same population of granules, one or more shapes chosen from a cylindrical, spherical or ovoid shape. The size of the granules is such that the longest average dimension is preferably 2 to 10 mm, preferably 2 to 8 mm, preferably 3 to 7 mm, even better 3.5 to 6 mm. The size of the granules may vary depending on the dimensions of the orifices of the rotating drum used. Generally, all the orifices of the rotating drum are of substantially identical dimensions, however, it is possible to vary these dimensions.

Preferably, the granules of material usable as a road binder or as a waterproofing binder, in particular bitumen, according to the invention have a weight of between 0.1 g and 50 g, preferably between 0.2 g and 10 g, more preferably between 0.2 g and 5 g.

First variant:

According to a first variant, the granules of material usable as a road binder or as a waterproofing binder are prepared from a first bitumen composition comprising one or more bitumen bases.

Preferably, the bitumen granules are prepared from a first bitumen composition comprising:

- one or more bitumen bases,

- from 0.1% to 5% by mass, preferably from 0.5% to 4% by mass, more preferably from 0.5% to 2.8% by mass, and even more preferably from 0.5% to 2.5% by mass of at least one chemical additive, the percentages being by mass relative to the total mass of bitumen base.

The bitumen base and chemical additive are as described below.

Preferably, the bitumen granules are prepared from a first bitumen composition comprising:

- one or more bitumen bases,

- from 0.1% to 5% by mass, preferably from 0.5% to 4% by mass, more preferably from 0.5% to 2.8% by mass, and even more preferably from 0.5% to 2.5% by mass of at least one chemical additive and,

- from 0.5% to 20% by mass, preferably from 2% to 20% by mass, more preferably from 4% to 15% by mass of at least one anti-caking agent, the percentages being by mass relative to the total mass of bitumen base.

According to another preferred embodiment, the granules are prepared from a first composition comprising:

- one or more bitumen bases,

- between 0.1% and 5% by mass, preferably between 0.5% and 4% by mass, more preferably between 0.5% and 2.8% by mass, and even more preferably between 0.5% and 2.5% by mass of at least one chemical additive,

- and between 0.05% and 15% by mass, preferably between 0.1% and 10% by mass, more preferably between 0.5% and 6% by mass of at least one olefinic polymer adjuvant, the percentages being by mass relative to the total mass of bitumen base.

According to another preferred embodiment, the granules are prepared from a first composition comprising:

- one or more bitumen bases,

- 30 to 40% of at least one polymer,

- from 4 to 6% of at least one compatibilizing agent,

- from 3% to 15% of at least one anti-caking agent, the percentages being by mass relative to the total mass of the first composition.

Optionally, the bitumen granules are prepared from a first composition of road bitumen and coated with a second composition comprising at least one anti-caking agent. This type of granule has a core/shell structure, also called core/coating layer.

According to this embodiment, the granules comprise, or better are essentially composed of:

- a heart prepared from a first composition,

- a coating layer prepared from a second composition comprising at least one anti-caking compound.

The bitumen granules are coated with the anti-caking agent according to any known method, for example according to the method described in document US 3,026,568.

According to a third embodiment, the bitumen granules are prepared from a first road bitumen composition and covered with a second composition comprising at least one anti-caking agent and at least one viscosifying agent. According to this embodiment, the granules comprise, or better are essentially composed of:

- a heart prepared from a first composition,

- a coating layer prepared from a second composition comprising at least one viscosifying compound and at least one anti-caking compound.

The different coating layers can be combined with all variants of the first compositions.

According to one embodiment of the invention, the solid bitumen granules may further comprise one or more other coating layers, based on anti-caking agent covering all or part of the coating layer of the solid bitumen according to the invention.

Advantageously, the different embodiments described above for the granules can be combined with each other.

Second variant:

According to a second variant, the granules of material usable as a road binder or as a waterproofing binder are prepared from a first composition comprising at least one pitch.

According to a first embodiment, the granules consist of a first pitch-based composition.

According to a second embodiment, the granules consist of a first composition based on pitch and at least one bitumen base.

According to a first embodiment of this second variant, the first composition comprises at least one pitch having a penetrability at 25°C ranging from 0 to 20 1/10 mm, a ring and ball softening temperature (RBT) ranging from 115°C to 175°C, it being understood that the penetrability is measured according to standard EN 1426 and that the RBT is measured according to standard EN 1427.

According to a second embodiment of this second variant, the first composition comprises:

- at least one pitch having a penetrability at 25°C ranging from 0 to 20 1/10 mm, a ring and ball softening temperature (RBT) ranging from 115°C to 175°C, it being understood that the penetrability is measured according to standard EN 1426 and that the RBT is measured according to standard EN 1427,

- at least one bitumen base, and

- at least one chemical additive chosen from an organic compound, a paraffin, a polyphosphoric acid and their mixtures.

Preferably, according to this second embodiment, the first composition comprises:

- at least one pitch having a penetrability at 25°C ranging from 0 to 20 1/10 mm, a ring and ball softening temperature (RBT) ranging from 115°C to 175°C, it being understood that the penetrability is measured according to standard EN 1426 and that the RBT is measured according to standard EN 1427,

- at least one bitumen base, and

- from 0.1% to 5% by mass, preferably from 0.5% to 4% by mass, more preferably from 0.5% to 2.8% by mass, and even more preferably from 0.5% to 2.5% by mass of at least one chemical additive chosen from an organic compound, a paraffin, a polyphosphoric acid and their mixtures, the percentages being by mass relative to the total mass of the first composition.

According to a first variant of this second embodiment, the first composition comprises:

- at least one pitch having a penetrability at 25°C ranging from 0 to 20 1/10 mm, a ring and ball softening temperature (RBT) ranging from 115°C to 175°C, it being understood that the penetrability is measured according to standard EN 1426 and that the RBT is measured according to standard EN 1427,

- at least one bitumen base,

- from 0.1% to 5% by mass, preferably from 0.5% to 4% by mass, more preferably from 0.5% to 2.8% by mass, and even more preferably from 0.5% to 2.5% by mass of at least one chemical additive chosen from an organic compound, a paraffin, a polyphosphoric acid and their mixtures, and

- from 0.5% to 20% by mass, preferably from 2% to 20% by mass, more preferably from 4% to 15% by mass of at least one anti-caking agent, the percentages being by mass relative to the total mass of the first composition.

According to a second variant of this second embodiment, the first composition comprises:

- at least one pitch having a penetrability at 25°C ranging from 0 to 20 1/10 mm, a ring and ball softening temperature (RBT) ranging from 115°C to 175°C, it being understood that the penetrability is measured according to standard EN 1426 and that the RBT is measured according to standard EN 1427,

- at least one bitumen base,

- from 0.1% to 5% by mass, preferably from 0.5% to 4% by mass, more preferably from 0.5% to 2.8% by mass, and even more preferably from 0.5% to 2.5% by mass, or even from 0.5 to 2.8% by mass of at least one chemical additive chosen from an organic compound, a paraffin, a polyphosphoric acid and their mixtures, and

- from 0.05% to 15% by mass, preferably from 0.1% to 10% by mass, more preferably from 0.5% to 6% by mass of at least one olefinic polymer adjuvant, the percentages being by mass relative to the total mass of the first composition.

Advantageously, the invention relates to pitch granules covered on at least part of their surface with an anti-caking agent as defined below, preferably over their entire surface.

Preferably, the mass of the anti-caking agent covering at least part of the surface of the pitch granules is between 0.2% and 10% by mass, preferably between 0.5% and 8% by mass, more preferably between 0.5% and 5% relative to the total mass of the pitch.

Advantageously, the mass of the anti-caking agent covering at least part of the surface of the pitch granules is approximately 1% by mass relative to the total mass of the pitch.

Preferably, the layer of anti-caking agent covering the pitch granules according to the invention is continuous so that at least 90% of the surface of said granules is covered with an anti-caking agent, preferably at least 95%, more preferably at least 99%.

Third variant:

According to a third variant, the granules of material usable as a road binder or as a waterproofing binder are prepared from a first composition comprising at least one clear binder.

Conventional bituminous binders, due to the presence of asphaltenes, are black in color and are therefore difficult to color. Colored coatings are increasingly used because, among other things, they improve the safety of road users by clearly identifying specific routes such as pedestrian paths, cycle paths, and bus lanes. They also help to mark certain danger zones such as city entrances or dangerous bends. Colored coatings improve visibility in low-light conditions, for example at night or in specific locations such as tunnels. Finally, they simply improve the aesthetic appearance of urban roads and can be used for public squares, building and school courtyards, sidewalks, pedestrian streets, garden and park paths, parking and rest areas.

Therefore, for all the above applications, it is preferred to use clear synthetic binders, which do not contain asphaltenes and can be colored.

According to this variant, the first composition comprises at least one clear binder.

Advantageously, the first composition comprises at least one clear binder base and at least one chemical additive chosen from an organic compound, a paraffin, a polyphosphoric acid and their mixtures.

According to one embodiment of the invention, the first composition comprises from 0.1% to 5% by mass, preferably from 0.5% to 4% by mass, more preferably from 0.5% to 2.8% by mass, and even more preferably from 0.5% to 2.5% by mass of said chemical additive relative to the total mass of said additive clear binder.

According to one embodiment of the invention, the first composition comprises

- at least one light binder base,

- between 5% and 30% by mass, preferably between 6% and 28% by mass, more preferably between 7% and 26% by mass of the chemical additive(s) relative to the total mass of said clear binder base.

In this case the first composition is called concentrated clear binder.

According to a preferred embodiment, the granules are prepared from a first composition comprising:

- one or more clear binder bases,

- 30 to 40% of at least one polymer,

- from 4 to 6% of at least one compatibilizing agent,

- from 3% to 15% of at least one anti-caking agent, the percentages being by mass relative to the total mass of the first composition.

A clear binder that is solid when cold and in divided form is a clear binder that is solid at room temperature and is packaged in divided form, i.e. in the form of separate units called granules.

The clear binder according to the invention is referred to indifferently in the present description as “clear binder solid when cold and in divided form” or “clear binder with additives”.

Preferably, the clear binder is a composition that can be used as a substitute for bitumen-based binders for the preparation, for example, of colored bituminous coating. A clear binder is free of asphaltenes and can therefore retain the natural color of the aggregate with which it is mixed or be easily colored using pigments.

As for granules whose first composition comprises a bitumen base, granules prepared from a first composition comprising at least one clear binder may be coated with a coating layer prepared from:

of a second composition comprising at least one anti-caking compound, or of a second composition comprising at least one viscosifying compound and at least one anti-caking compound,

The bitumen base

Advantageously, the core or heart of the solid bitumen granules according to the invention is prepared from a first composition, which is a road bitumen composition, said first composition being prepared by bringing into contact:

one or more bitumen bases, and possibly at least one chemical additive.

For the purposes of the invention, the terms “bitumen” and “road bitumen” are used equivalently and independently of each other. By “bitumen” or “road bitumen” is meant any bituminous compositions consisting of one or more bitumen bases and possibly comprising one or more chemical additives, said compositions being intended for road application.

Among the bitumen bases that can be used according to the invention, mention may firstly be made of bitumens of natural origin, those contained in deposits of natural bitumen, natural asphalt or oil sands and bitumens originating from the refining of crude oil. The bitumen bases according to the invention are advantageously chosen from bitumen bases originating from the refining of crude oil. The bitumen bases may be chosen from bitumen bases or mixtures of bitumen bases originating from the refining of crude oil, in particular bitumen bases containing asphaltenes or pitches. The bitumen bases may be obtained by conventional processes for manufacturing bitumen bases in refineries, in particular by direct distillation and/or vacuum distillation of oil. These bitumen bases may optionally be visbroken and/or deasphalted and/or rectified in air. It is common practice to vacuum distill atmospheric residues from the atmospheric distillation of crude oil. This manufacturing process therefore corresponds to the succession of atmospheric distillation and vacuum distillation, the feedstock feeding the vacuum distillation corresponding to the atmospheric residues. These vacuum residues from the vacuum distillation tower can also be used as bitumens. It is also common to inject air into a feedstock usually composed of distillates and heavy products from the vacuum distillation of atmospheric residues from petroleum distillation. This process makes it possible to obtain a blown, or semi-blown, or oxidized, or air-rectified, or partially air-rectified base.

The different bitumen bases obtained by refining processes can be combined to obtain the best technical compromise. The bitumen base can also be a recycled bitumen base. Bitumen bases can be hard grade or soft grade bitumen bases.

According to the invention, for conventional processes for manufacturing bitumen bases, the process is carried out at manufacturing temperatures of between 100°C and 270°C, preferably between 100°C and 200°C, preferably between 140°C and 200°C, more preferably between 140°C and 170°C, and with stirring for a period of at least 10 minutes, preferably between 30 minutes and 10 hours, more preferably between 1 hour and 6 hours. Manufacturing temperature means the heating temperature of the bitumen base(s) before mixing as well as the mixing temperature. The temperature and duration of heating vary according to the quantity of bitumen used and are defined by standard NF EN 12594.

According to the invention, blown bitumens can be manufactured in a blowing unit, by passing a flow of air and/or oxygen through a starting bituminous base. This operation can be carried out in the presence of an oxidation catalyst, for example phosphoric acid. Generally, blowing is carried out at high temperatures, of the order of 200 to 300°C, for relatively long periods of time typically between 30 minutes and 2 hours, continuously or in batches. The blowing duration and temperature are adjusted according to the properties targeted for the blown bitumen and according to the quality of the starting bitumen.

Preferably, the bitumen base used to manufacture the granules of the invention has a needle penetrability measured at 25°C according to standard EN 1426 of 5 to 330 1/10 mm, preferably of 20 to 220 1/10 mm.

As is well known, the so-called "needle penetrability" measurement is carried out using a standardized NF EN 1426 test at 25°C (P25) This penetrability characteristic is expressed in tenths of a millimeter (dmm or 1/10 mm). Needle penetrability, measured at 25°C, according to the standardized NF EN 1426 test, represents the measurement of penetration into a sample of bitumen, after a time of 5 seconds, of a needle whose weight with its support is 100 g. The NF EN 1426 standard replaces the approved standard NF T 66-004 of December 1986 with effect from December 20, 1999 (decision of the Director General of AFNOR dated November 20, 1999).

The clear binder base

A clear binder base is understood to mean compositions comprising a plasticizing agent, for example an oil of petroleum or vegetable origin, a structuring agent, for example a hydrocarbon resin, and a polymer. The composition of the clear binder bases determines certain essential properties of these binders, in particular the plasticity index, the viscosity of the binder, or the color which must be as light as possible.

According to one embodiment of the invention, the clear binder base comprises:

- a plasticizing agent, for example a natural or synthetic oil, free from asphaltenes,

- a structuring agent, for example a hydrocarbon or vegetable resin,

- a copolymer,

- where appropriate, doping agents, or dopes, or adhesiveness dopes.

Clear binder compositions are described in the following applications and patents and these clear binder compositions can be used as the clear binder base in the present invention.

As a clear binder base, a clear binder comprising hydrogenated white oils comprising at least 60% paraffinic carbons (according to the ASTM D2140 method), and a hydrocarbon resin, optionally mixed with copolymers of the ethylene-vinyl acetate (EVA) or low density polyethylene type, for example of the EPDM (ethylene-propylene-diene-monomer) type, as described in WO 01/53409, may be used.

As a clear binder base, a clear binder comprising an oil with a naphthenic content of between 35% and 80% and a hydrocarbon resin may be used, as described in EP 1783174.

As a clear binder base, a clear binder comprising a synthetic oil, a resin and a polymer of SBS or SIS type, as described in EP 1473327, may be used.

As a clear binder base, a clear binder comprising:

- at least one oil of petroleum origin, preferably an aromatic oil comprising aromatic extracts of petroleum residues, obtained by extraction or dearomatization of residues from distillations of petroleum cuts,

- at least one resin of plant origin, preferably chosen from rosin esters, glycerol and rosin esters, pentaerythritol and rosin esters, taken alone or as a mixture, and

- at least one latex, preferably chosen from acrylic polymer latexes, natural rubber latexes, synthetic rubber latexes, taken alone or as a mixture, as described in WO 2009/150519.

As a clear binder base, a clear synthetic binder comprising:

- at least one oil of vegetable origin preferably chosen from rapeseed, sunflower, soybean, linseed, olive, palm, castor, wood, corn, pumpkin, grape seed, jojoba, sesame, walnut, hazelnut, almond, shea, macadamia, cotton, alfalfa, rye, safflower, peanut, coconut and copra oils, and mixtures thereof,

- at least one resin of petroleum origin, preferably chosen from hydrocarbon resins of petroleum origin resulting from the copolymerization of aromatic, aliphatic, cyclopentadienic petroleum fractions taken alone or as a mixture and,

- at least one polymer, preferably chosen from styrene and butadiene copolymers, styrene and isoprene copolymers, ethylene/propene/diene terpolymers, polychloroprenes, ethylene and vinyl acetate copolymers, ethylene and methyl acrylate copolymers, ethylene and butyl acrylate copolymers, ethylene/methyl acrylate/glycidyl methacrylate terpolymers, ethylene/butyl acrylate/maleic anhydride terpolymers, atactic polypropylenes, taken alone or as mixtures, the quantity of oil of vegetable origin in the binder being greater than or equal to 10% by mass and the quantity of polymer in the binder being less than or equal to 15% by mass, as described in WO 2010/055491.

According to another embodiment of the invention, the clear binder base comprises:

(i) a plasticizing agent consisting of an oil containing a total content of paraffinic compounds, measured according to the ASTM D2140 method, of at least 50%, preferably at least 60% by weight, more preferably between 50% and 90%, preferably between 60% and 80%, and (ii) a copolymer based on conjugated diene units and monovinyl aromatic hydrocarbon units, for example based on butadiene units and styrene units.

Preferably, the oil is a synthetic oil from deasphalting unit cuts (or “DAO oil”).

Preferably, the oil contains a total content of paraffinic compounds greater than or equal to 50%, preferably greater than or equal to 60% by weight, and a total content of naphthenic compounds less than or equal to 25% by weight, measured according to the ASTM D2140 method.

Preferably, the oil contains a total content of paraffinic compounds greater than or equal to 50%, preferably greater than or equal to 60% by weight, a total content of naphthenic compounds less than or equal to 25% by weight, and a total content of aromatic compounds less than or equal to 25% by weight, measured according to the ASTM D2140 method.

For example, the oil contains a total paraffinic content, measured according to the ASTM D2140 method, of between 50% and 90%, preferably between 60% and 80% by weight, a total naphthenic content of between 5% and 25% by weight, and a total aromatic content of between 5% and 25% by weight.

Preferably, the oil has an aniline point, measured according to ISO2977:1997, greater than or equal to 80°C, preferably greater than or equal to 90°C, for example greater than 100°C.

Preferably, the clear binder base preferably comprises (i) from 40 to 80% by weight of plasticizing agent, (ii) from 20 to 50% by weight of resin, (iii) from 1 to 7% by weight of copolymer; and, (iv) optionally from 0.05% to 0.5% by weight of tackifier, for example amine, relative to the weight of the clear binder base.

Advantageously, the clear binder base preferably comprises (i) from 40 to 80% by weight of plasticizing agent, (ii) from 20 to 50% by weight of resin, (iii) from 1 to 7% by weight of copolymer;

and, (iv) from 0.05% to 0.5% by weight of tackifier, for example amine, relative to the basis weight of clear binder.

Advantageously, the clear binder base also comprises (i) from 45% to 70% by weight of plasticizing agent, (ii) from 25 to 50% by weight of resin, (iii) from 1% to 7% by weight of copolymer; and, (iv) optionally from 0.1% to 0.3% by weight of tackifier, relative to the total weight of clear binder base.

Preferably, the clear binder base consists essentially of (i) 40 to 80% by weight of plasticizing agent, (ii) 20 to 50% by weight of resin, (iii) 1 to 7% by weight of copolymer, based on the total weight of clear binder base.

Advantageously, the clear binder base consists essentially of (i) from 40 to 80% by weight of plasticizing agent, (ii) from 20 to 50% by weight of resin, (iii) from 1 to 7% by weight of copolymer and (iv) from 0.05% to 0.5% by weight of tackifier, relative to the total weight of clear binder base.

Advantageously, the clear binder base essentially also consists of (i) from 45% to 70% by weight of plasticizing agent, (ii) from 25 to 50% by weight of resin (iii) from 1% to 7% by weight of copolymer; and, (iv) from 0.1% to 0.3% by weight of tackifier, relative to the total weight of clear binder base.

Preferably, the copolymer is a copolymer based on styrene and butadiene units which comprises a weight content of 1-2 butadiene ranging from 5 to 70%.

Preferably, the copolymer is advantageously a copolymer based on styrene and butadiene units which comprises a weight content of 1,2-butadiene ranging from 5 to 70% and a weight content of 1,2-vinyl group of between 10 and 40%.

For example, said copolymer based on styrene and butadiene units has a mass-average molecular weight of between 10,000 and 500,000, preferably between 50,000 and 200,000, and more preferably between 50,000 and 150,000 daltons. Preferably, a styrene/butadiene block or styrene/butadiene/styrene block copolymer will be used.

The clear binders according to the invention are advantageously characterized in that they have a color index less than or equal to 4, preferably less than or equal to 3, as determined according to the ASTM DH4 scale.

In addition, they can advantageously have a softening temperature Ball-Ring Temperature determined according to standard NF EN1427 between 55°C and 90°C.

Preferably, the clear binder that can be used according to the invention has a penetrability at 25°C, measured according to standard NF EN 1426, of between 10 and 220 1/10 mm, preferably between 30 and 100 1/10 mm, more preferably between 40 and 80 1/10 mm. A person skilled in the art can modulate the penetrability of the clear binder that can be used in the invention, in particular by judiciously choosing the weight ratio [structuring agent/plasticizing agent] in the composition of the clear binder base. Indeed, it is known that an increase in this ratio makes it possible to reduce the penetrability at 25°C.

The clear binder bases used in the invention can be prepared for example according to the following process comprising the steps of:

(i) mixing the plasticizing agent, for example DAO oil, and heating to a temperature between 140-200°C, for example from 10 minutes to 30 minutes, (ii) adding the structuring agent, for example the hydrocarbon resin, mixing and heating to a temperature between 140-200°C, for example from 30 minutes to 2 hours, (iii) adding the polymer(s), for example SBS, mixing and heating to a temperature between 140-200°C, for example, from 90 minutes to 3 hours, preferably from 90 minutes to 2 hours 30, (iv) optionally adding an adhesive dope, mixing and heating to a temperature between 140-200°C, for example, from 5 minutes to 20 minutes.

The order of steps (i) to (iv) may be changed.

According to one embodiment of the invention, the clear binder granules further comprise at least one coloring agent as described above, such as for example a pigment.

In these embodiments, the anti-caking agent and/or the coloring agent will be chosen by a person skilled in the art according to the color of the desired clear binder.

The pitch

According to the French dictionary, "pitch" means a residue from the distillation of tars from petroleum, oil, coal, wood or other organic molecules.

The invention relates herein to petroleum distillation residues, also called "petroleum pitch".

For the purposes of the invention, the terms “pitch”, “petroleum pitch” and “deasphalting pitch” will be used independently of one another.

Pitch can be obtained by conventional refinery manufacturing processes. The manufacturing process consists of a succession of atmospheric distillation and vacuum distillation. First, the crude oil is subjected to atmospheric pressure distillation, which results in a gaseous phase, various distillates, and an atmospheric distillate residue. Then, the atmospheric distillation residue is itself subjected to reduced pressure distillation, called vacuum distillation, which separates a heavy diesel, various distillate cuts, and a vacuum distillation residue. This vacuum distillation residue contains "petroleum pitch" in varying concentrations.

It is possible to obtain “petroleum pitch” using two processes:

^the process:

The vacuum distillation residue is subjected to a desalting operation by adding a suitable solvent, such as propane, which thus allows the pitch to precipitate and separate it from the light fractions such as deasphalted oil.

^2nd process:

The vacuum distillation residue is subjected to solvent extraction, specifically furfural. This heterocyclic aldehyde has the particularity of selectively solubilizing aromatic and polycyclic compounds. This process thus makes it possible to eliminate aromatic extracts and recover the "petroleum pitch".

According to one embodiment, the pitch is an oxidized pitch.

Preferably, the oxidized pitch according to the invention is obtained by oxidation of a mixture comprising pitch and a diluent, such as a light gasoline, also called “fluxant” subjected to an oxidation operation in a blowing tower in the presence of a catalyst, at a fixed temperature and at a given pressure.

For example, oxidized pitches can be produced in a blowing unit, by passing a stream of air and/or oxygen through a starting pitch. This operation can be carried out in the presence of an oxidation catalyst, for example phosphoric acid. Generally, oxidation is carried out at high temperatures, in the order of 200 to 300°C, for relatively long periods of time typically between 30 minutes and 2 hours, continuously or in batches. The oxidation time and temperature are adjusted according to the desired properties of the oxidized pitch and the quality of the starting pitch.

The mechanical qualities of pitches are generally assessed by determining a series of mechanical characteristics using standardized tests, the most commonly used of which are needle penetrability expressed in 1/10 mm and the softening point determined by the ring and ball test, also called ring and ball softening temperature (RBT).

According to one embodiment of the invention, the pitch has a needle penetrability at 25°C of 0 to 20 1/10 mm, preferably of 0 to 15 1/10 mm, more preferably of 0 to 10 1/10 mm, it being understood that the penetrability is measured according to standard EN 1426.

According to one embodiment of the invention, the pitch has a softening point of between 115°C and 175°C. Examples of pitches used in the invention include pitches having a softening point of between 115°C and 125°C, between 135 and 145°C, or between 165 and 175°C.

The plasticizing agent

For the purposes of the invention, the term “plasticizing agent” means a chemical constituent making it possible to fluidify and reduce the viscosity and modulus of the binder obtained.

In one embodiment of the invention, the plasticizing agent is chosen from oils of petroleum origin, oils of vegetable origin and their mixture.

In a preferred embodiment of the invention, the oils of plant origin are chosen from rapeseed, sunflower, soybean, linseed, olive, palm, castor, wood, corn, pumpkin, grape seed, jojoba, sesame, walnut, hazelnut, almond, shea, macadamia, cotton, alfalfa, rye, safflower, peanut, coconut and copra oils, and mixtures thereof.

Preferably, the oils of vegetable origin are chosen from rapeseed, sunflower, linseed, coconut, soybean oils, and their mixtures.

In a preferred embodiment of the invention, the oils of petroleum origin are chosen from aromatic oils or oils of synthetic origin.

Preferably, the aromatic oils comprise aromatic extracts of petroleum residues, obtained by extraction or dearomatization of residues from distillations of petroleum cuts.

More preferably, the aromatic oils have an aromatic compound content of between 30 and 95% by weight, advantageously between 50 and 90% by weight, more advantageously between 60 and 85% by weight (SARA method: Saturates/Aromatics/Resins/Asphaltenes).

More preferably, the aromatic oils have a content of saturated compounds of between 1 and 20% by weight, advantageously of between 3 and 15% by weight, more advantageously of between 5 and 10% by weight (SARA method: Saturates/Aromatics/Resins/Asphaltenes).

More preferably, the aromatic oils have a resin compound content of between 1 and 10% by weight, advantageously between 3 and 5% by weight, (SARA method: Saturates/Aromatics/Resins/Asphaltenes).

In a preferred embodiment of the invention, the oils of synthetic origin are derived from the deasphalting cuts of reduced pressure distillation (vacuum residue, RSV) of crude oil (hereinafter referred to as “DAO oil”).

In particular, in a preferred embodiment, the plasticizing agent consists solely of a DAO oil.

The contents of paraffinic, naphthenic and aromatic compounds mentioned in this application are determined according to ASTM D2140 standard, in % by weight relative to the weight of the oil.

In a specific embodiment, the plasticizing agent is an oil, for example a DAO oil, containing a total content of paraffinic compounds of at least 50% by weight, preferably at least 60% by weight, for example between 50% and 90%, preferably between 60% and 90%, more preferably between 50% and 80% and in particular between 55% and 70% or in particular between 60% and 75%.

In a more specific embodiment, the plasticizing agent is an oil, for example a DAO oil, further containing a total content of naphthenic compounds which does not exceed 25%, for example between 5% and 25%, and in particular between 10% and 25%.

In a more specific embodiment, the plasticizing agent is an oil, for example a DAO oil, further containing a total aromatic content which does not exceed 25%, for example between 5% and 25%, and in particular between 8% and 18%.

In a particularly preferred embodiment, the plasticizing agent is an oil, for example a DAO oil, comprising the respective contents:

(i) a total content of paraffinic compounds of between 50% and 90%;

(ii) a total content of naphthenic compounds of between 5% and 25%, for example between 15% and 25%; and (iii) a total content of aromatic compounds of between 5% and 25%, for example between 10% and 15%.

In a more particularly preferred embodiment, the plasticizing agent is an oil, for example a DAO oil, comprising the respective contents:

(i) a total content of paraffinic compounds of between 60% and 75%;

(ii) a total content of naphthenic compounds of between 5% and 25%, for example between 15% and 25%; and (iii) a total content of aromatic compounds of between 5% and 25%, for example between 10% and 15%.

Oils meeting the above characteristics and usable for the preparation of the clear binder according to the invention are obtained by vacuum residue (VRR) deasphalting processes from oil refining, for example by deasphalting using a C3 to C6 solvent, preferably propane. These deasphalting processes are well known to those skilled in the art and are described for example in Lee et al 2014, Fuel Processing Technology

119: 204-210: The residues from vacuum distillation (VDR) are separated according to their molecular weight in the presence of C3 to C6 solvents (e.g. propane). The so-called DAO (“deasphalted oil”) thus obtained is rich in paraffin, has a very low asphaltene content, an evaporation temperature between 440°C and 750°C, and an API gravity much higher than that of the vacuum residues.

The respective contents of paraffinic, naphthenic and aromatic compounds depend to a certain extent on the nature of the crude oil from which the DAO oil originates and on the refining process used. A person skilled in the art knows how to determine the respective contents of paraffinic, naphthenic and aromatic compounds in a DAO oil, for example using the SARA fractionation method also described in Lee et al 2014, Fuel Processing Technology 119: 204-210, and thus select the appropriate DAO oil for the preparation of the clear binder according to the invention.

In one embodiment, the amount of plasticizing agent used in the process for preparing the clear binder base is from 40% to 80%, preferably from 45% to 70% by weight relative to the total weight of clear binder base.

The structuring agent

By “structuring agent” we mean any chemical constituent conferring mechanical properties and satisfactory cohesiveness to said binder.

The structuring agent used in the context of the invention is a resin, preferably chosen from resins of hydrocarbon petroleum origin, for example derived from the copolymerization of aromatic, aliphatic, cyclopentadienic petroleum fractions, taken alone or as a mixture, preferably derived from aromatic petroleum couples. For example, it may be a polycycloaliphatic thermoplastic resin, for example of the hydrogenated cyclopentadiene homopolymer type, with low molecular weight.

More specifically, the cyclopentane type hydrocarbon resin has a softening point (or Ring-Ball temperature, RBT, according to standard NF T 66-008) greater than 125°C, and a Gardner color index (according to standard NF T 20-030) equal to a maximum of 1.

Other examples of resins that can be used as structuring agents include, but are not limited to, resins of plant origin obtained from plants and/or plants. They can be referred to as harvested resins, meaning they are harvested from the living plant. They can be used as they are, in which case they are referred to as natural resins, or chemically transformed, in which case they are referred to as modified natural resins.

Harvesting resins include acrylate resins, dammar, natural rosins, modified rosins, rosin esters, and metal rosinates. These can be taken alone or in a mixture.

Natural rosins include gem and wood rosins, especially pine, and/or tall oil. These natural rosins can be used alone or in a mixture.

Modified rosins include hydrogenated rosins, disproportionated rosins, polymerized rosins, and/or maleated rosins. These modified natural rosins may be taken alone or in a mixture, and may undergo one or more disproportionation, polymerization, and/or maleization treatments.

Rosin esters include natural rosin methyl esters, hydrogenated rosin methyl esters, natural rosin glycerol esters, hydrogenated rosin glycerol esters, disproportionated rosin glycerol esters, polymerized rosin glycerol esters, maleated rosin glycerol esters, natural rosin pentaerythritol esters, and hydrogenated rosin pentaerythritol esters. These rosin esters may be taken alone or as a mixture and may be derived from rosins that have undergone one or more disproportionation, polymerization, and/or maleization treatments.

Esters of pentaerythritol and natural rosins and esters of pentaerythritol and hydrogenated rosins are the preferred rosin esters.

Among the metal resinates, mention may be made of metal carboxylates, for example of Ca, Zn, Mg, Ba, Pb, Co, obtained from natural rosins or modified rosins. Preferred are calcium resinates, zinc resinates, mixed calcium/zinc resinates, taken alone or as a mixture.

The weight ratio between the structuring agent and the plasticizing agent used for the preparation of the clear binder according to the invention is generally from 0.3 to 1.5, for example from 0.5 to 1.

In a specific embodiment, the amount of structuring agent used in the process for preparing the clear binder base is 25 to 50% by weight relative to the total weight of clear binder base.

The polymer

The polymer used in the process for preparing the first composition is a copolymer based on conjugated diene units and monovinyl aromatic hydrocarbon units. The conjugated diene is preferably chosen from those comprising 4 to 8 carbon atoms per monomer, for example butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene and 1,2-hexadiene, chloroprene, carboxylated butadiene, carboxylated isoprene, in particular butadiene and isoprene, and mixtures thereof.

The monovinyl aromatic hydrocarbon is preferably selected from styrene, o-methyl styrene, p-methyl styrene, p-tert-butylstyrene, 2,3 dimethylstyrene, a-methyl styrene, vinyl naphthalene, vinyl toluene, vinyl xylene, and the like or mixtures thereof, in particular styrene.

More particularly, the polymer consists of one or more copolymers chosen from block copolymers of styrene and butadiene, of styrene and isoprene, of styrene and chloroprene, of styrene and carboxylated butadiene or of styrene and carboxylated isoprene. A preferred copolymer is a copolymer based on butadiene units and styrene units such as the styrene/butadiene SB block copolymer or the styrene/butadiene/styrene SBS block copolymer.

The copolymer of styrene and conjugated diene, in particular the copolymer of styrene and butadiene, advantageously has a styrene content by weight ranging from 5 to 50%, preferably from 20 to 50%.

The styrene-conjugated diene copolymer, in particular the styrene-butadiene copolymer, advantageously has a butadiene content by weight (1-2 and 1-4) ranging from 50 to 95%. The styrene-conjugated diene copolymer, in particular the styrene-butadiene copolymer, advantageously has a butadiene content by weight 1-2 ranging from 5 to 70%, preferably from 5 to 50%. The butadiene units 1-2 are the units that result from the polymerization via the 1-2 addition of the butadiene units.

The mass average molecular mass of the copolymer of styrene and conjugated diene, and in particular that of the copolymer of styrene and butadiene, may be, for example, between 10,000 and 500,000, preferably between 50,000 and 200,000 and more preferably from 50,000 to 150,000 daltons.

In a specific embodiment, the total amount of polymer used in the process of the invention is from 0.5 to 20% by mass, preferably from 1 to 10%, preferably from 1 to 7%, for example from 2% to 5% relative to the total mass of bitumen base, or clear binder.

In another specific embodiment, the total quantity of polymer used in the process of the invention is from 20% to 50% by mass, relative to the total mass of bitumen base, or relative to the total mass of clear binder base.

In this case, the first composition is called bitumen/polymer composition stock solution or clear binder/polymer composition stock solution. It is intended to be transported and stored in concentrated form, then diluted with the desired quantity of bitumen base or clear binder base just before its use as a road binder or as a coating binder. According to the invention, it is possible to form granules of bitumen or clear binder stock solution, so as to facilitate their transport and hot storage as well as their handling.

According to a variant of the invention, the polymer is chosen from micronized polymers. Preferably, according to this variant the polymer has particles with a diameter ranging from 250 to 1000 μm, preferably with a diameter ranging from 400 to 600 μm.

Compatibilizing agent

Preferably, the compatibilizing agent is chosen from waxes, for example animal waxes, vegetable waxes, mineral waxes and mixtures thereof.

Animal and vegetable waxes are mainly composed of mixtures of fatty acid derivatives (fatty acid esters) while mineral waxes are paraffinic derivatives.

Stickiness drugs

To improve the mutual affinity between the binder and the aggregates and ensure their durability, adhesive dopes can also be used in the first composition, mixed with the other components, in particular the clear binder, or the bitumen base or the pitch. These are, for example, nitrogenous surfactant compounds derived from fatty acids (amines, polyamines, alkylpolyamines, etc.).

When added to the first composition, the adhesive dopes generally represent between 0.05% and 0.5% by weight relative to the weight of clear binder or bitumen base or pitch. For example, in a specific embodiment, from 0.05% to 0.5% of amine, preferably from 0.1% to 0.3% of amine, will be added relative to the total mass of clear binder base or bitumen base or pitch.

Coloring agents

The clear synthetic binder may also include one or more coloring agents, such as mineral pigments or organic dyes. The pigments are selected according to the desired shade or color for the coating. For example, metal oxides such as iron oxides, chromium oxides, cobalt oxides, titanium oxides will be used to obtain the colors red, yellow, gray, blue-green or white. The pigments can be added, indifferently in the clear binder or in the asphalt (mixed with aggregates for example) or in an emulsion of the clear binder.

The chemical additive

The bitumen base or the clear binder or the mixture of bitumen base and pitch may also comprise at least one chemical additive chosen from: an organic compound, a paraffin, a polyphosphoric acid and their mixtures.

In particular, when the solid material comprises at least one chemical additive, the latter is in a quantity adapted so that its penetrability is preferably 5 to 50 1/10 mm and/or that the ring and ball softening temperature (RBT) is preferably greater than or equal to 60°C, it being understood that the penetrability is measured at 25°C according to standard EN 1426 and the RBT according to standard EN 1427.

According to a first embodiment of the invention, the chemical additive is an organic compound. Advantageously, the organic compound has a molar mass less than or equal to 2000 gmol' ¹ , preferably a molar mass less than or equal to 1000 gmof ¹ .

In this first embodiment, according to a first variant, the organic compound is a compound of general formula (I):

Arl-R-Ar2 (I), in which:

• Arl and Ar2 represent, independently of each other, a benzene ring or a system of condensed aromatic rings of 6 to 20 carbon atoms, substituted by at least one hydroxyl group, and • R represents an optionally substituted divalent radical, the main chain of which comprises from 6 to 20 carbon atoms and at least one group chosen from the amide, ester, hydrazide, urea, carbamate and anhydride functions.

Preferably, Arl and/or Ar2 are substituted by at least one alkyl group of 1 to 10 carbon atoms, advantageously in one or more ortho positions relative to the hydroxyl group(s), more preferably Arl and Ar2 are 3,5-dialkyl-4-hydroxyphenyl groups, advantageously 3,5-di-Zer/-butyl-4-hydroxyphenyl groups.

Preferably, R is in the para position relative to a hydroxyl group of Arl and/or Ar2.

Advantageously, the compound of formula (I) is 2’,3-bis[(3-[3^ 5-di-tert-butyl-4hydroxyphenyl]propionyl)]propionohydrazide.

According to a second variant of this first embodiment, the organic compound is a compound of general formula (II):

R-(NH) _n CONH-(X) _m -NHCO(NH) _n -R' (II), in which,

- the groups R and R’, identical or different, contain a saturated or unsaturated, linear, branched or cyclic hydrocarbon chain, comprising from 1 to 22 carbon atoms, optionally substituted, and optionally comprising heteroatoms, cycles and/or heterocycles;

- the group X contains a hydrocarbon chain, saturated or unsaturated, linear, cyclic or branched, comprising from 1 to 22 carbon atoms, optionally substituted, and optionally comprising heteroatoms, cycles and/or heterocycles;

- n and m are integers having a value of 0 or 1 independently of each other.

According to this variant, when the integer m has a value of 0, then the groups R(NH) _n CONH and NHCO(NH) _n -R' are covalently linked by a hydrazide bond CONHNHCO. The group R, or the group R', then comprises at least one group chosen from: a hydrocarbon chain of at least 4 carbon atoms, an aliphatic cycle of 3 to 8 atoms, an aliphatic, partially aromatic or entirely aromatic condensed polycyclic system, each cycle comprising 5 or 6 atoms.

Still according to this variant, when the integer m has a value of 1, then the group R, the group R' and/or the group X, comprises at least one group chosen from: a hydrocarbon chain of at least 4 carbon atoms, an aliphatic cycle of 3 to 8 atoms, an aliphatic, partially aromatic or entirely aromatic condensed polycyclic system, each cycle comprising 5 or 6 atoms.

Preferably, the group R and/or R’ comprises an aliphatic hydrocarbon chain of 4 to 22 carbon atoms, in particular chosen from the groups C4H9, C5H11, C9H19, C11H23, C12H25, C17H35, C18H37, C21H43, C22H45.

Preferably, the group X represents a linear, saturated hydrocarbon chain comprising from 1 to 22 carbon atoms. Preferably, the group X is chosen from the groups C2H4, C3H6.

Preferably, the group X can also be a cyclohexyl group or a phenyl group, the radicals R-(NH) _n CONH- and NHCO(NH) _n -R'- can then be in the ortho, meta or para position. Furthermore, the radicals R-(NH) _n CONH- and NHCO(NH) _n -R'- can be in the cis or trans position relative to each other. In addition, when the radical X is cyclic, this cycle can be substituted by groups other than the two main groups R(NH) _n CONH- and -NHCO(NH) _n -R'.

Preferably, the group X comprises two 6-carbon rings linked by a CH2 group, these rings being aliphatic or aromatic. In this case, the group X is a group comprising two aliphatic rings linked by an optionally substituted _CH2 group, such as for example:

Advantageously, according to this variant, the organic compound is a compound of general formula (II) chosen from hydrazide derivatives such as the compounds C5H11-CONH-NHCOC ₅ Hn, C ₉ H ₁₉ -CONH-NHCO-C9Hi9, C _n H ₂₃ -CONH-NHCO-CuH23, C ₁₇ H ₃₅ -CONH-NHCOC17H35, or C21H ₄₃ -CONH-NHCO-C21H ₄ 3; diamides such as N,N'-ethylenedi(stearamide) of formula C17H ₃ 5-CONH-CH ₂ -CH2-NHCO-Ci7H3 ₅ ; and ureide derivatives such as 4,4'bis(dodecylaminocarbonylamino)diphenylmethane of formula C12H25-NHCONH-C6H4-CH2C6H4-NHCONH-C12H25.

Preferably, the compound of general formula (II) is chosen from those which satisfy the condition n = 0.

Preferably, the compound of general formula (II) is chosen from those which satisfy the condition: the sum of the numbers of carbon atoms of R, X and R' is greater than or equal to 10, advantageously greater than or equal to 14, preferably greater than or equal to 18.

Preferably, the compound of general formula (II) is chosen from those which satisfy the condition: the number of carbon atoms of at least one of R and R' is greater than or equal to 10, advantageously greater than or equal to 12, preferably greater than or equal to 14.

Preferably, according to a first variant, the compound of general formula (II) is chosen from those of formula (IIA):

R-CONH-(X) _m -NHCO-R' (IIA) in which R, R', m and X have the same definition as above.

Preferably, in formula (IIA) when m= 1, the group X represents a linear, saturated hydrocarbon chain comprising from 1 to 22 carbon atoms, advantageously X represents a linear, saturated hydrocarbon chain comprising from 1 to 12 carbon atoms, even better from 1 to 4 carbon atoms. Preferably, the group X is chosen from the groups C ₂ H ₄ , C3H6.

Preferably, the compound of general formula (IIA) is chosen from those which satisfy the condition: the sum of the numbers of carbon atoms of R, X and R' is greater than or equal to 10, advantageously greater than or equal to 14, preferably greater than or equal to 18.

Preferably, the compound of general formula (IIA) is chosen from those which satisfy the condition: the number of carbon atoms of at least one of R and R' is greater than or equal to 10, advantageously greater than or equal to 12, preferably greater than or equal to 14.

More preferably, according to this variant, the compound of general formula (IIA) is chosen from hydrazide derivatives such as the compounds C5H11-CONH-NHCO-C5H11, C9H19CONH-NHCO-C9H19, CiiH ₂ 3-CONH-NHCO-CiiH ₂₃ , C ₁₇ H35-CONH-NHCO-Ci ₇ H ₃₅ , or C ₂₁ H ₄₃ CONH-NHCO-C21H43 ; diamides such as N,N'-ethylenedi(laurylamide) of formula CiiH ₂₃ -CONH-CH ₂ -CH ₂ -NHCO-CiiH ₂₃ , N,N'-ethylenedi(myristylamide) of formula C1 ₃ H ₂₇ CONH-CH ₂ -CH ₂ -NHCO-Ci ₃ H ₂₇ , N,N'-ethylenedi(palmitamide) of formula C15H31-CONHCH ₂ -CH ₂ -NHCO-Ci5H3i, N,N'-ethylenedi(stearamide) of formula C1 ₇ H3 ₅ -CONH-CH ₂ -CH ₂ NHCO-Ci ₇ H ₃ 5 ; monoamides such as laurylamide of formula ChH ₂₃ -CONH ₂ , myristylamide of formula Ci3H ₂₇ -CONH ₂ , palmitamide of formula Ci5H3i-CONH ₂ , stearamide of formula Ci ₇ H35-CONH ₂ .

Even more advantageously, the compound of general formula (IIA) is N,N'ethylenedi(stearamide) of formula Ci ₇ H35-CONH-CH ₂ -CH ₂ -NHCO-Ci ₇ H35.

Preferably, according to a second variant, the compound of general formula (II) is chosen from those of formula (IIB):

R-CONH-R’ (IIB) in which R and R’ have the same definition as above.

Advantageously, according to this variant, the sum of the numbers of carbon atoms of R and R' is greater than or equal to 10, advantageously greater than or equal to 14, preferably greater than or equal to 18.

Even more advantageously, according to this variant, the number of carbon atoms of R is greater than or equal to 10, advantageously greater than or equal to 12, preferably greater than or equal to 14, and R’ = H.

Advantageously, the compound of general formula (II) is chosen from hydrazide derivatives such as the compounds C5H11-CONH-NHCO-C5H11, C9H19-CONH-NHCO-C9H19, C11H23-CONH-NHCO-C11H23, C ₁₇ H ₃₅ -CONH-NHCO-C ₁₇ H ₃₅ , or C ₂ iH ₄₃ -CONH-NHCOC21H43; diamides such as N,N'-ethylenedi(laurylamide) of formula C11H23-CONH-CH2CH2-NHCO-C11H23, N,N'-ethylenedi(myristylamide) of formula C] ₃ H ₂₇ -CONH-CH ₂ -CH2NHCO-Ci3H2 ₇ , N,N'-ethylenedi(palmitamide) of formula C15H31-CONH-CH2-CH2-NHCOC15H31, N,N'-ethylenedi(stearamide) of formula _C17H35 -CONH-CH2-CH2-NHCO-C| ₇ H35; monoamides such as laurylamide of formula C11H23-CONH2, myristylamide of formula _{C13H27 -CONH2 ,} palmitamide of formula _C15H3i - _CONH2 , stearamide _{of formula C17H35CONH2 .}

Even more advantageously, the compound of general formula (II) is N,N'ethylenedi(stearamide) of formula C1 ₇ H ₃ 5-CONH-CH2-CH2-NHCO-C1 ₇ H ₃ 5.

Preferably, when the chemical additive is chosen from organic compounds of formula (II), it is used in combination with at least one other chemical additive chosen from organic compounds of formula (I), (III), (V), (VI) and (VII) and/or the reaction products of at least one C3-C12 polyol and at least one C2-C12 aldehyde, in particular those comprising a group of formula (IV).

According to a third variant of this embodiment, the organic compound is a compound of formula (III):

(R-NHCO) _X -Z-(NHCO-R') _y (III), in which,

- R and R’, identical or different, contain a saturated or unsaturated, linear, branched or cyclic hydrocarbon chain comprising from 1 to 22 carbon atoms, optionally substituted, and optionally comprising heteroatoms, cycles and/or heterocycles,

- Z represents a tri-functionalized group chosen from the following groups:

- x and y are different integers with values ranging from 0 to 3 and such that x+y=3.

Preferably, when x is 0 and Z represents Z ₂ , the compound of formula (III) is N2,N4,N6-tridecylmelamine having the following formula with R' representing the group C9H19:

Other preferred compounds corresponding to formula (III) are such that x is equal to 0, Z represents Z ₂ and R' represents a saturated, linear hydrocarbon chain of 1 to 22 carbon atoms, preferably of 2 to 18 carbon atoms, preferably of 5 to 12 carbon atoms.

Other preferred compounds corresponding to formula (III) are such that: y is equal to 0 and Z represents Zi, the compounds then have the formula:

H

O HN^

R with R chosen from the following groups, taken alone or in mixtures:

Other preferred compounds corresponding to formula (III) are such that: y is equal to 0, Z represents Zi and R represents a saturated, linear hydrocarbon chain of 1 to 22 carbon atoms, preferably of 8 to 12 carbon atoms.

According to a fourth variant of this embodiment, the organic compound is a reaction product of at least one C3-C12 polyol and at least one C2-C12 aldehyde. Among the polyols that can be used, mention may be made of sorbitol, xylitol, mannitol and/or ribitol. Preferably, the polyol is sorbitol.

Advantageously, according to this variant, the organic compound is a compound which comprises at least one function of general formula (IV):

R (IV)

With :

- x is an integer,

- R is chosen from a C1-C11 alkyl, alkenyl, aryl, or aralkyl radical, optionally substituted by one or more halogen atoms, one or more C1-C6 alkoxy groups.

The organic compound is advantageously a sorbitol derivative. By "sorbitol derivative" is meant any reaction product obtained from sorbitol. In particular, any reaction product obtained by reacting an aldehyde with D-sorbitol. This condensation reaction produces sorbitol acetals, which are sorbitol derivatives. 1,3:2,4-DiO-benzylidene-D-sorbitol is obtained by reacting 1 mole of D-sorbitol and 2 moles of benzaldehyde and has the formula:

Sorbitol derivatives can thus be all condensation products of aldehydes, in particular aromatic aldehydes with sorbitol. We will then obtain sorbitol derivatives with the general formula:

where Ari and Ar2 are optionally substituted aromatic rings.

Among the sorbitol derivatives, other than 1,3:2,4-Di-O-benzylidene-D-sorbitol, we can find for example 1,3:2,4:5,6-tri-O-benzylidene-D-sorbitol, 2,4-mono-O-benzylidene-Dsorbitol, 1,3:2,4-bis(p-methylbenzylidene) sorbitol, 1,3:2,4-bis(3,4-dimethylbenzylidene) sorbitol, 1,3:2,4-bis(p-ethylbenzylidene) sorbitol, 1,3:2,4-bis(p-propylbenzylidene) sorbitol, 1,3:2,4-bis(p-butylbenzylidene) sorbitol, 1,3:2,4-bis(p-ethoxylbenzylidene) sorbitol, 1,3:2,4bis(p-chlorobenzylidene) sorbitol, l,3:2,4-bis(p-bromobenzylidene) sorbitol, 1,3:2,4-Di-Omethylbenzylidene-D-sorbitol, 1,3:2,4-Di-O-dimethylbenzylidene-D-sorbitol, 1,3:2,4-Di-O-(4methylbenzylidene)-D-sorbitol, 1,3:2,4-Di-O-(4,3-dimethylbenzylidene)-D-sorbitol. Preferably, according to this variant, the organic compound is 1,3:2,4-Di-O-benzylidene-Dsorbitol.

According to a fifth variant of this embodiment, the organic compound is a compound of general formula (V):

R”-(COOH) _Z (V), in which R” represents a linear or branched, saturated or unsaturated chain comprising from 4 to 68 carbon atoms, preferably from 4 to 54 carbon atoms, more preferably from 4 to 36 carbon atoms and z is an integer ranging from 2 to 4.

Preferably, the group R” is preferably a saturated linear chain of formula C _W H2 _W with w an integer ranging from 4 to 22, preferably from 4 to 12.

According to this variant of the invention, the organic compounds corresponding to formula (V) can be diacids (z = 2), triacids (z = 3) or tetraacids (z = 4). The preferred organic compounds according to this variant are diacids with z = 2.

Preferably, according to this variant, the diacids have the general formula HOOCC _w H ₂ w-COOH with w an integer varying from 4 to 22, preferably from 4 to 12 and where z = 2 and R = C _w H2w·

Advantageously, according to this variant, the organic compound is a diacid chosen from adipic acid or 1,6-hexanedioic acid with w = 4, pimelic acid or 1,7-heptanedioic acid with w = 5, suberic acid or 1,8-octanedioic acid with w = 6, azelaic acid or 1,9-nonanedioic acid with w = 7, sebacic acid or 1,10-decanedioic acid with w = 8, undecanedioic acid with w = 9, 1,2-dodecanedioic acid with w = 10 or tetradecanedioic acid with w = 12.

Advantageously, the diacid is sebacic acid.

The diacids may also be diacid dimers of unsaturated fatty acid(s), i.e. dimers formed from at least one unsaturated fatty acid, for example from a single unsaturated fatty acid or from two different unsaturated fatty acids. The diacid dimers of unsaturated fatty acid(s) are conventionally obtained by intermolecular dimerization reaction of at least one unsaturated fatty acid (Diels Aider reaction for example). Preferably, only one type of unsaturated fatty acid is dimerized. They are derived in particular from the dimerization of an unsaturated fatty acid, in particular Cg to C34, in particular C12 to C22, in particular C16 to _C20 , and more particularly _C18 . A preferred fatty acid dimer is obtained by dimerization of linoleic acid, which can then be partially or completely hydrogenated. Another preferred fatty acid dimer has the formula HOOC-(CH2)7CH=CH-(CH2)7-COOH. Another preferred fatty acid dimer is obtained by dimerization of methyl linoleate. Similarly, fatty acid triacids and fatty acid tetraacids may be found, obtained by trimerization and tetramerization of at least one fatty acid, respectively.

According to a sixth variant of this embodiment, the organic compound is a compound of general formula (VI):

(CH ₂ ) _p

(VI) in which,

- the groups Y and Y’ represent, independently of one another, an atom or group chosen from: H, -(CH2)q-CH3, -(CH2)q-NH2, -(CHajq-OH, -(CH2)q-COOH or

O with q an integer ranging from 2 to 18, preferably from 2 to 10, preferably from 2 to 4 and p an integer greater than or equal to 2, preferably having a value of 2 or 3.

Among the preferred organic compounds corresponding to formula (VI), the following compounds may be mentioned:

Preferably, according to this variant, the organic compound of general formula (VI) is:

According to a seventh variant of this embodiment, the organic compound is a compound of general formula (VII):

R-NH-CO-CO-NH-R’ (VII) in which R and R’, identical or different, represent a saturated or unsaturated, linear, branched or cyclic hydrocarbon chain, comprising from 1 to 22 carbon atoms, preferably from 8 to 12 carbon atoms, optionally substituted, and optionally comprising heteroatoms, cycles and/or heterocycles.

According to another embodiment of the invention, the chemical additive is a paraffin. The paraffins have chain lengths of 30 to 120 carbon atoms (C30 to C120). The paraffins are advantageously chosen from polyalkylenes. Preferably, polymethylene paraffins and polyethylene paraffins will be used according to the invention. These paraffins may be of petroleum origin or come from the chemical industry. Advantageously, the paraffins used are synthetic paraffins resulting from the conversion of biomass and/or natural gas.

Preferably, these paraffins contain a large proportion of so-called "normal" paraffins, i.e., straight-chain, unbranched linear paraffins (saturated hydrocarbons). Thus, the paraffins may comprise from 50 to 100% normal paraffins and from 0 to 50% isoparaffins and/or branched paraffins. More preferably, the paraffins comprise from 85 to 95% normal paraffins and from 5 to 15% isoparaffins and/or branched paraffins. Advantageously, the paraffins comprise from 50 to 100% normal paraffins and from 0 to 50% isoparaffins. Even more advantageously, the paraffins comprise from 85 to 95% normal paraffins and from 5 to 15% isoparaffins.

Preferably, the paraffins are polymethylene paraffins. More particularly, the paraffins are synthetic polymethylene paraffins, for example paraffins resulting from the conversion of synthesis gas by the Fischer-Tropsch process. In the Fischer-Tropsch process, the paraffins are obtained by reacting hydrogen with carbon monoxide over a metal catalyst. Fischer-Tropsch synthesis processes are described, for example, in publications EP 1 432 778, EP 1 328 607 or EP 0 199 475.

According to another embodiment of the invention, the chemical additive is a polyphosphoric acid. The polyphosphoric acids (PPA) that can be used in the invention are described in WO 97/14753. They are compounds of empirical formula PqHrOs in which q, r and s are positive numbers such that:

q > 2 and in particular q goes from 3 to 20 or more and that 5q+r-2s=0.

In particular, said polyphosphoric acids may be linear compounds of empirical formula P _q H( _{q +} 2)O(3 _q + i) corresponding to the developed formula:

Where q has the definition given above. They can still be products of two-dimensional or three-dimensional structure.

All these polyphosphoric acids can be considered as polycondensation products by heating aqueous metaphosphoric acid.

It will not be outside the scope of the invention to combine several different chemical additives such as different organic compounds of formula (I), (II), (III), (V), (VI) and (VII), the reaction products of at least one C3-C12 polyol and at least one C2-C12 aldehyde, in particular those comprising a group of formula (IV), and/or different paraffins and/or different polyphosphoric acids in the bitumen base.

According to one embodiment of the invention, the first composition, comprising a bitumen base, of which the core of the granules is composed, comprises from 0.1% to 10% by mass, preferably from 0.5% to 5% by mass, more preferably from 0.5% to 2.5% by mass of chemical additive relative to the total mass of the first composition.

According to an advantageous embodiment, the first composition comprises at least two chemical additives.

According to a first variant of this embodiment, the first composition comprises at least one first chemical additive of formula (V) and at least one second chemical additive chosen from: the chemical additives of formula (I); the chemical additives of formula (II); the chemical additives of formula (III); the chemical additives of formula (V); the chemical additives of formula (VI); the chemical additives of formula (VII) and the reaction products of at least one C3-C12 polyol and at least one C2-C12 aldehyde, in particular those comprising a group of formula (IV), the second chemical additive being distinct from the first chemical additive.

Preferably, and according to this first variant, the first composition comprises at least one first chemical additive of formula (V) and at least one second chemical additive of formula (II).

More preferably, and according to this first variant, the first composition comprises at least one first additive of formula (V) and at least one second chemical additive of formula (IIA).

Preferably, and still according to this first variant, the first chemical additive of formula (V) is chosen from diacids (z=2), triacids (z=3) and tetracids (z=4), preferably from diacids (z=2).

More preferably, and still according to this first variant, the first chemical additive of formula (V) is chosen from adipic acid or 1,6-hexanedioic acid with w =

4, pimelic acid or 1,7-heptanedioic acid with w = 5, suberic acid or 1,8-octanedioic acid with w = 6, azelaic acid or 1,9-nonanedioic acid with w = 7, sebacic acid or 1,10-decanedioic acid with w = 8, undecanedioic acid with w = 9, 1,2-dodecanedioic acid with w = 10 or tetradecanedioic acid with w = 12.

Advantageously, and according to this first variant, the first chemical additive of formula (V) is sebacic acid or 1,10-decanedioic acid with w = 8.

According to a second variant of this embodiment, the first composition comprises at least one first chemical additive of formula (II) and at least one second chemical additive chosen from: the chemical additives of formula (I); the chemical additives of formula (II); the chemical additives of formula (III); the chemical additives of formula (V); the chemical additives of formula (VI); the chemical additives of formula (VII) and the reaction products of at least one C3-C12 polyol and at least one C2-C12 aldehyde, in particular those comprising a group of formula (IV), the second chemical additive being distinct from the first chemical additive.

Preferably, and according to this second variant, the first chemical additive of formula (II) is chosen from the chemical additives of formula (IIA).

More preferably, and according to this second variant, the first composition comprises at least one first chemical additive of formula (IIA) and at least one second chemical additive chosen from: the chemical additives of formula (I); the chemical additives of formula (IIB); the chemical additives of formula (III); the chemical additives of formula (V); the chemical additives of formula (VI); the chemical additives of formula (VII) and the reaction products of at least one C3-C12 polyol and at least one C2-C12 aldehyde, in particular those comprising a group of formula (IV), the second chemical additive being distinct from the first chemical additive.

Even more preferably, and according to this second variant, the first composition comprises at least one first additive of formula (IIA) and at least one second additive of formula (V).

Advantageously, and according to this second variant, the first chemical additive of formula (II) is N,N’-ethylenedi(stearamide).

According to a third preferred variant of this embodiment, the first composition comprises at least sebacic acid or 1,10-decanedioic acid and at least N,N-ethylenedi(stearamide).

According to a fourth variant of this embodiment, the first composition comprises at least one first additive of formula (I) and at least one second chemical additive chosen from:

chemical additives of formula (I); chemical additives of formula (II); chemical additives of formula (III); chemical additives of formula (V); chemical additives of formula (VI); chemical additives of formula (VII) and the reaction products of at least one C3-C12 polyol and at least one C2-C12 aldehyde, in particular those comprising a group of formula (IV), the second chemical additive being distinct from the first chemical additive.

Preferably, and according to this fourth variant, the second chemical additive is chosen from the chemical additives of formula (II) and the chemical additives of formula (V).

Preferably, and according to this fourth variant, the second chemical additive of formula (II) is chosen from the chemical additives of formula (IIA).

More preferably, and according to this fourth variant, the second chemical additive of formula (II) is N,N’-ethylenedi(stearamide).

Preferably, and still according to this fourth variant, the second chemical additive of formula (V) is chosen from diacids (z=2), triacids (z=3) and tetracids (z=4), preferably from diacids (z=2).

Even more preferably, and still according to this fourth variant, the second chemical additive of formula (V) is chosen from adipic acid or 1,6-hexanedioic acid with w = 4, pimelic acid or 1,7-heptanedioic acid with w = 5, suberic acid or 1,8-octanedioic acid with w = 6, azelaic acid or 1,9-nonanedioic acid with w = 7, sebacic acid or 1,10-decanedioic acid with w = 8, undecanedioic acid with w = 9, 1,2-dodecanedioic acid with w = 10 or tetradecanedioic acid with w = 12.

Advantageously, and still according to this fourth variant, the second chemical additive of formula (V) is sebacic acid or 1,10-decanedioic acid.

Preferably, and according to this fourth variant, the first chemical additive of formula (I) is 2’,3-bis[(3-[3, 5-di-tert-butyl-4-hydroxyphenyl]propionyl)]propionohydrazide.

Preferably, and according to this embodiment, the mass ratio of the first chemical additive relative to the second chemical additive is from 1:99 to 99:1, preferably from 1:9 to 9:1, even more preferably from 1:5 to 5:1.

Olefinic polymer adjuvant

According to one embodiment of the invention, the first composition may further comprise at least one olefinic polymer adjuvant.

The olefinic polymer adjuvant is preferably selected from the group consisting of (a) ethylene/glycidyl (meth)acrylate copolymers; (b) ethylene/monomer terpolymers

A/monomer B and (c) copolymers resulting from the grafting of a monomer B onto a polymer substrate.

(a) The ethylene/glycidyl (meth)acrylate copolymers are advantageously chosen from random or block copolymers, preferably random, of ethylene and a monomer chosen from glycidyl acrylate and glycidyl methacrylate, comprising from 50% to 99.7% by mass, preferably from 60% to 95% by mass, more preferably 60% to 90% by mass of ethylene.

(b) The terpolymers are advantageously chosen from random or block terpolymers, preferably random, of ethylene, of a monomer A and of a monomer B.

Monomer A is selected from vinyl acetate and C 1 -C 6 alkyl acrylates or methacrylates. Monomer B is selected from glycidyl acrylate and glycidyl methacrylate.

The ethylene/monomer A/monomer B terpolymers comprise from 0.5% to 40% by mass, preferably from 5% to 35% by mass, more preferably from 10% to 30% by mass of units derived from monomer A and from 0.5% to 15% by mass, preferably from 2.5% to 15% by mass of units derived from monomer B, the remainder being formed from units derived from ethylene.

(c) The copolymers result from the grafting of a monomer B chosen from glycidyl acrylate and glycidyl methacrylate, onto a polymer substrate. The polymer substrate consists of a polymer chosen from polyethylenes, in particular low-density polyethylenes, polypropylenes, random or block copolymers, preferably random, of ethylene and vinyl acetate and random or block copolymers, preferably random, of ethylene and C 1 to C 5 alkyl acrylate or methacrylate comprising from 40% to 99.7% by mass, preferably from 50% to 99% by mass of ethylene. Said graft copolymers comprise from 0.5% to 15% by mass, preferably from 2.5% to 15% by mass of grafted units derived from monomer B.

Advantageously, the olefinic polymer adjuvant is chosen from random terpolymers of ethylene (b), of a monomer A chosen from C 1 to C 6 alkyl acrylates or methacrylates and of a monomer B chosen from glycidyl acrylate and glycidyl methacrylate, comprising from 0.5% to 40% by mass, preferably from 5% to 35% by mass, more preferably from 10% to 30% by mass of units derived from monomer A and from 0.5% to 15% by mass, preferably from 2.5% to 15% by mass of units derived from monomer B, the remainder being formed from units derived from ethylene.

According to one embodiment of the invention, the first composition, comprising the bitumen base, of which the core of the granules is composed, comprises from 0.05% to 15% by mass, preferably from 0.1% to 10% by mass, more preferably from 0.5% to 6% by mass of the olefinic polymer adjuvant, relative to the total mass of the first composition.

According to one embodiment of the invention, the first composition may also comprise other known additives or other known bitumen elastomers such as SB copolymers (styrene and butadiene block copolymer), SBS (styrene-butadiene-styrene block copolymer), SIS (styrene-isoprene-styrene), SBS* (styrene-butadiene-styrene star block copolymer), SBR (styrene-b-butadiene-rubber), EPDM (modified ethylene propylene diene). These elastomers may further be crosslinked according to any known method, for example with sulfur. Mention may also be made of elastomers made from styrene monomers and butadiene monomers allowing crosslinking without crosslinking agent as described in documents WO2007/058994, WO2008/137394 and by the applicant in patent application WO11/013073.

According to a particular preferred embodiment, the first composition comprises a combination of the chemical additive of formula (II) and the olefinic polymer adjuvant described above.

The combination in which the chemical additive is of formula (II) where m=0, more preferably where m=0 and n=0, will be preferred.

The combination in which the olefinic polymer adjuvant is chosen from the ethylene/monomer A/monomer B terpolymers (b) described above will also be preferred.

More preferably, the road bitumen comprises the chemical additive of formula (II) where m=0, more preferably where m=0 and n=0 and the olefinic polymer adjuvant chosen from the terpolymers (b) ethylene/monomer A/monomer B described above.

The anti-caking compound:

The anti-caking compound is of mineral or organic origin. By "anticaking agent" or "anticaking compound" is meant any compound that limits, reduces, inhibits, delays the agglomeration and/or adhesion of granules to each other during transport and/or storage at room temperature and which ensures their fluidity during handling.

More preferably, the anti-caking compound is chosen from: talc; fines, also called fillers, generally with a diameter of less than 125 μm, such as siliceous fines, with the exception of calcareous fines; sand such as Fontainebleau sand; cement; carbon; wood residues such as lignin, lignosulfonate, conifer needle powders, conifer cone powders, in particular pine; rice husk ash; glass powder; clays such as kaolin, bentonite, vermiculite; alumina such as alumina hydrates; silica; silica derivatives such as silica fumes, functionalized silica fumes, in particular hydrophobic or hydrophilic silica fumes, fumed silicas, in particular hydrophobic or hydrophilic fumed silicas, silicates, silicon hydroxides and silicon oxides; plastic powder; lime; plaster; rubber crumb; polymer powder, such as styrene-butadiene (SB) copolymers, styrene-butadiene-styrene (SBS) copolymers and mixtures of these materials.

Advantageously, the anti-caking agent is chosen from talc; fines generally with a diameter of less than 125 μm with the exception of calcareous fines, such as siliceous fines; wood residues such as lignin, lignosulfonate, conifer needle powders, conifer cone powders, in particular pine; glass powder; sand such as Fontainebleau sand; silica fumes, in particular hydrophobic or hydrophilic silica fumes; and mixtures thereof.

Preferably, the anti-caking compound is chosen from silica fumes.

For the purposes of the invention, the compounds “silica fume” and “pyrogenic silica” have the same chemical definition and are registered under the same CAS number 112 945-52-5. Consequently, for the purposes of the invention, these compounds can be used interchangeably with each other.

By "fumed silica" is meant either a fumed silica or a fumed silica derivative.

"Fumed silica" means a compound obtained by the vapor-phase hydrolysis of chlorosilanes such as silicon tetrachloride, in an oxygen and hydrogen flame. Such processes are generally referred to as pyrogenic processes, the overall reaction of which is: SiCfi + 1¾ + O2 —> S1O2 + 4 HCl.

Fumed silicas differ from other silicon dioxides in that they have an amorphous structure. They are of high purity (> 99.8% silica) and have a low hydrophilic character (no microporosity).

Preferably, the fumed silica compound is fumed silica.

According to one embodiment of the invention, the pyrogenic silica compound has a specific surface area of between 25 and 420 m /g, preferably between 90 and 330 m /g, more preferably between 120 and 280 m /g.

The specific surface area of fumed silica defined in ^m2 /g commonly called “surface area” or “SA” is measured according to the method of S. Brunauer, PH Emmet and I. Teller, J. Am. Chemical Society, 60: 309 (1938) (BET).

According to one embodiment of the invention, the pyrogenic silica compound has an average particle size of between 5 and 50 nm.

According to one embodiment of the invention, the pyrogenic silica compound has a pH of between 3 and 10 when it is in aqueous phase.

According to one embodiment of the invention, the fumed silica compound has a carbon content of between 0.1 and 10% by weight relative to the total weight of the fumed silica compound.

According to one embodiment of the invention, the pyrogenic silica compound is chosen from a hydrophilic pyrogenic silica compound, a hydrophobic pyrogenic silica compound and mixtures thereof.

Preferably, the fumed silica compound is a hydrophilic fumed silica compound.

By "hydrophilic" we mean a compound that is miscible with water in all proportions.

The fumed silica compound, or fumed silica derivative, used in the sense of the invention may be chemically modified.

Different types of fumed silica compounds are described in the following patent applications and can be used in the present invention:

- silanized pyrogenic silicas, as described in WO 2004/020532, or in WO 2007/128636,

- hydrophilic pyrogenic silicas, as described in WO 2009/071467, WO 2011/000133 filed in the name of Degussa AG or Degussa Gmbh,

- silica fumes made hydrophobic by treatment with polysiloxanes as described in WO 2008/141932, or by silanization as described in WO 2008/141930,

- silicas doped with potassium oxide as described in WO 2008/043635, WO 2008/022836,

- silicas in the form of aggregates of primary particles as described in WO 2009/015969 filed in the name of Evonik Degussa Gmbh or in WO 2010/028261 filed in the name of Cabot Corporation.

The fumed silica compound can be used alone or in the form of a mixture within a coating composition.

Whether used alone or as a mixture in a composition, the fumed silica compound can be used in the process according to the invention in the form of a powder or in dispersion in a solvent which evaporates after application.

Preferably, when the composition comprises at least one fumed silica compound and at least one solvent, the composition comprises from 5 to 70% by weight of fumed silica compound relative to the total weight of the composition, more preferably from 20 to 40% by weight.

Preferably, the solvent is an organic solvent or water. By organic solvent is meant any solvent immiscible with a bitumen, such as an alcohol, for example ethanol.

The fumed silica compounds used in the invention are commercially available and for example can be sold by Evonik Degussa under the brand name AEROSIL, such as for example AEROSIL®200, by Cabot Corporation under the brands CAB-O-SIL® and CAB-O-SPERSE® or by Wacker Chemie AG under the brand name HDK®.

According to one embodiment of the invention, the mass of the fumed silica compound covering at least part of the surface of the granules is between 0.2% and 10% by mass, preferably between 0.5% and 8% by mass, more preferably between 0.5% and 5% relative to the total mass of the first composition.

The granules of the first composition are coated with the fumed silica compound according to any known method, for example according to the method described in document US 3,026,568.

According to one embodiment of the invention, the core of the granules further comprises at least one pyrogenic silica compound as defined above.

Preferably, the core of the granules of the first composition further comprises between 0.5% and 20% by mass, preferably between 2% and 20% by mass, more preferably between 4% and 15% by mass of the fumed silica compound relative to the total mass of the first composition.

Viscosifying compound:

The terms “viscosifier” and “viscosifying compound” are used for the purposes of the invention, in an equivalent manner and independently of one another. By “viscosifier” or “viscosifying compound” is meant a compound which has the property of reducing the fluidity of a liquid or composition and therefore of increasing its viscosity.

The viscosifier within the meaning of the invention is a material which has a dynamic viscosity greater than or equal to 50 mPa.s' ¹ , preferably from 50 mPa.s' ¹ to 550 mPa.s' ¹ , more preferably from 80 mPa.s' ¹ to 450 mPa.s' ¹ , the viscosity being a Brookfield viscosity measured at 65°C. The viscosity of a viscosifier according to the invention is measured at 65°C using a Brookfield CAP 2000+ viscometer and at a rotation speed of 750 rpm. The measurement is read after 30 seconds for each temperature.

Preferably, the viscosifier is chosen from:

gelling compounds preferably of plant or animal origin, such as: gelatin, agar-agar, alginates, cellulose derivatives, starches, modified starches, or gellan gums;

- polyethylene glycols (PEG) such as PEGs having a molecular weight of between 800 g.mol' ¹ and 8000 g.mol' ¹ , such as for example a PEG having a molecular weight of 800 g.mol' ¹ (PEG-800), a PEG having a molecular weight of 1000 g.mol' ¹ (PEG-1000), a PEG having a molecular weight of 1500 g.mol' ¹ (PEG-1500), a PEG having a molecular weight of 4000 g.mol' ¹ (PEG-4000) or a PEG having a molecular weight of 6000 g.mol' ¹ (PEG-6000);

- mixtures of such compounds.

Advantageously, the viscosifier is chosen from:

- gelling compounds preferably of plant or animal origin, such as: gelatin, agar-agar, alginates, cellulose derivatives or gellan gums;

- polyethylene glycols (PEG) such as PEGs having a molecular weight of between 800 g.mol' ¹ and 8000 g.mol' ¹ , such as for example a PEG having a molecular weight of 800 g.mol' ¹ (PEG-800), a PEG having a molecular weight of 1000 g.mol' ¹ (PEG-1000), a PEG having a molecular weight of 1500 g.mol' ¹ (PEG-1500), a PEG having a molecular weight of 4000 g.mol' ¹ (PEG-4000) or a PEG having a molecular weight of 6000 g.mol' ¹ (PEG-6000);

- mixtures of such compounds.

The coating layer:

According to a first embodiment of the invention, the coating layer is obtained by applying a composition (second composition) comprising at least one anti-caking compound to all or part of the surface of the core of the granules, in particular solid bitumen.

Preferably, according to this embodiment, the coating layer consists essentially of one or more anti-caking compounds.

Preferably, according to this embodiment, the mass of the anti-caking compound covering at least part of the surface of the granules is from 0.2% to 20% by mass, preferably from 0.5% to 20% by mass, preferably from 2% to 20% by mass, more preferably from 4% to 15% by mass relative to the total mass of the granule cores, in particular the bitumen base of the granules.

According to this embodiment, and when the anti-caking compound is chosen from fumed silica compounds, the mass of the fumed silica compound covering at least part of the surface of the granules is between 0.2% and 10% by mass, preferably between 0.5% and 8% by mass, more preferably between 0.5% and 5% relative to the total mass of the first composition.

According to a second embodiment of the invention, the coating layer is obtained by applying a composition (second composition) comprising at least one viscosifying compound and at least one anti-caking compound to all or part of the surface of the core of the granules, in particular solid bitumen.

Preferably, the coating layer, formed from the second composition, is solid at room temperature, including elevated room temperature.

Preferably, the second composition, comprising at least one viscosifying compound and at least one anti-caking compound, has a viscosity greater than or equal to 200 mPa.s' ¹ , preferably between 200 mPa.s' ¹ and 700 mPa.s ¹ , the viscosity being a Brookfield viscosity.

Preferably, the second composition comprises at least 10% by mass of at least one viscosifying compound relative to the total mass of the second composition, preferably from 10 to 90% by mass, more preferably from 10 to 85% by mass.

Advantageously, when the viscosifier is a gelling agent, such as for example gelatin, the second composition comprises from 10 to 90% by mass of viscosifying compound relative to the total mass of the second composition, preferably from 15 to 85%, even better from 15 to 60%.

Advantageously, when the vicosifier is a gelling agent, such as for example gelatin, the second composition comprises from 10 to 90% by mass of anti-caking compound relative to the total mass of the second composition, preferably from 15 to 85%, even better from 40 to 85%.

Advantageously, when the viscosifier is a PEG, such as for example a PEG having a molecular weight of between 800 g.mof ¹ and 8000 g.mof ¹ , the second composition comprises from 10 to 90% by mass of viscosifying compound relative to the total mass of the second composition, preferably from 40 to 90%, even better from 60 to 90%.

Advantageously, when the vicosifier is a PEG, such as for example a PEG having a molecular weight of between 800 g.mof ¹ and 8000 g.mof ¹ , the second composition comprises from 10 to 90% by mass of anti-caking compound relative to the total mass of the second composition, preferably from 10 to 60%, even better from 10 to 40%.

Preferably, the second composition comprises at least 10% by mass of an anti-caking compound relative to the total mass of the second composition, preferably from 10 to 90% by mass, even more preferably from 15 to 90% by mass.

Preferably, according to this embodiment, the coating layer represents at least 5% by mass relative to the total mass of the granule, preferably from 10 to 60% by mass, more preferably from 10 to 50%.

In addition to the viscosifying compound and the anti-caking compound, the second composition forming the coating layer may optionally comprise one or more compounds chosen from: chemical additives, polymers, etc.

Advantageously, the viscosifying compound and the anti-caking compound represent at least 90% by mass relative to the total mass of the second composition forming the coating layer, even better at least 95% by mass and advantageously at least 98% by mass.

According to a preferred embodiment of this second variant, the second composition is essentially made up of the viscosifying compound and the anti-caking compound.

Uses of solid bitumen granules

The granules of solid material, preferably bitumen, obtained by the process of the invention can be used as a road binder.

The road binder can be used to make asphalt, in association with aggregates using any known process.

Preferably, the granules of solid material at room temperature according to the invention are used for the manufacture of coatings.

Bituminous mixes are used as materials for the construction and maintenance of road surfaces and their surfacing, as well as for all road works. Examples include surface dressings, hot mixes, cold mixes, cold-poured mixes, emulsified gravel, base, bonding, tack and rolling courses, and other combinations of a bituminous binder and road aggregate with specific properties, such as anti-rutting layers, draining mixes, or asphalts (a mixture of a bituminous binder and sand-type aggregates).

The granules of solid material, in particular solid bitumen, obtained by the process of the invention can be used in a process for manufacturing asphalt mixes comprising at least one road binder and aggregates, the road binder being chosen from the granules of solid material, in particular bitumens according to the invention, this process comprising at least the steps of:

- heating the aggregates to a temperature ranging from 100°C to 180°C, preferably from 120°C to 160°C,

- mixing the aggregates with the road binder in a tank such as a mixer or a mixer drum,

- obtaining coated materials.

The method of the invention has the advantage of being able to be implemented without a prior step of heating the granules of solid material, in particular solid bitumen.

The process of manufacturing asphalt mixes does not require a step of heating the granules of solid material, in particular solid bitumen, before mixing with the aggregates because on contact with the hot aggregates, the solid material, in particular solid bitumen at room temperature, melts.

The solid material, in particular the bitumen solid at room temperature obtained by the process according to the invention as described above, has the advantage of being able to be added directly to the hot aggregates, without having to be melted prior to mixing with the hot aggregates.

Preferably, the step of mixing the aggregates and the road binder is carried out with stirring, then stirring is maintained for at most 5 minutes, preferably at most 1 minute to allow a homogeneous mixture to be obtained.

The solid material, in particular solid bitumen, in the form of granules obtained according to the process of the present invention is remarkable in that it allows the transport and/or storage of solid material, in particular road bitumen, at ambient temperature under optimal conditions, in particular without there being agglomeration and/or adhesion of the solid material, in particular solid bitumen, during its transport and/or storage, even when the ambient temperature is high. Furthermore, the coating layer of the granules breaks under the effect of contact with the hot aggregates and of shearing and it releases the first composition, in particular the bitumen base. Finally, the presence of the coating layer in the mixture of road binder and aggregates does not degrade the properties of said road bitumen for a road application, compared to an uncoated bitumen base.

Method of transporting and/or storing and/or handling solid material usable as a road binder or as a coating binder

The granules obtained by the process of the invention can be transported and/or stored and/or handled in the form of granules of solid material, in particular bitumen, solid at room temperature.

Solid material, including road bitumen, can be transported and/or stored at high ambient temperature for a period of 2 months or more, preferably 3 months.

Preferably, the elevated ambient temperature is from 20°C to 90°C, preferably from 20°C to 80°C, more preferably from 40°C to 80°C, even more preferably from 40°C to 60°C.

The granules of solid material, in particular bitumen, obtained by the process according to the invention have the advantage of retaining their divided shape, and therefore of being able to be handled, after storage and/or transport at a high ambient temperature. In particular, they have the capacity to flow under their own weight without creeping, which allows them to be stored in packaging in bags, drums or containers of all shapes and sizes and then transferred from this packaging to equipment, such as construction site equipment (tank, mixer, etc.).

The granules of solid material, in particular bitumen, are preferably transported and/or stored in bulk in bags of 1 kg to 100 kg or 500 kg to 1000 kg, commonly referred to in the field of road bitumens as "Big Bags", said bags preferably being made of hot-melt material. They can also be transported and/or stored in bulk in boxes of 5 kg to 30 kg or in drums of 100 kg to 200 kg.

The various embodiments, variations, preferences and advantages described above for each of the objects of the invention apply to all of the objects of the invention and may be taken separately or in combination.

The invention is illustrated by the following examples given without limitation.

Device

The invention also relates to a device for implementing the method described above. This device described in Figures 1 to 3 is an apparatus for the extrusion in the form of pellets, also called "pelletization", onto a tread, of a fluid mass of solid material at room temperature, usable as a road binder or as a sealing binder, such as a road bitumen, a pitch, a mother solution for a bitumen/polymer composition, a clear binder. Such a device constitutes an improvement of the device described in US-4,279,579. This device 1 comprises: a first cylindrical drum 4A arranged above the tread 6 and capable of rotation about a longitudinal axis, said first drum 4A comprising a plurality of first passages 5A through the periphery of the drum 4A, a second cylindrical drum 4B coaxial with the first drum 4A, comprising means 17 for longitudinally admitting into said second drum 4B the mass to be extruded and comprising on a part of its wall a plurality of second passages 5B directed towards the tread 6 and radially aligned with said first passages 5A, said wall part 19 being arranged adjacent to said first drum 4A, said first drum 4A being mounted to allow its continuous rotation through 360 ° about the longitudinal axis relative to said second drum 4B such that the relative rotation between said drums 4A and 4B sequentially produces a misalignment and an alignment of the first passages 5A and second passages 5B for allowing the fluid mass to move radially outwardly through the aligned passages, 5A, 5B and onto the tread 6A, this device further comprising, as illustrated in Figure 1:

- a tank 11 equipped with heating means (not shown), and stirring means 13, making it possible to bring the container of the tank 11 to a fluid state,

- an injection channel, or several injection channels, 3 allowing the transfer of the fluid bitumen composition 2 inside the second drum 4B,

- a tank 14 into which an additive composition 15 can be introduced, the tank 14 being connected to the injection channel 3 via an injector 16 and allowing injection of the additive composition 15 into the bitumen composition 2 at the channel 3, located downstream of the tank 11 and upstream of the double drum 4.

As described in US-4,279,579, preferably, this device further comprises a spatula for removing excess mass from the perimeter of said first drum 4A, said spatula being directed towards said first drum 4A generally in the direction of rotation thereof, said spatula being firmly pressed against the perimeter of said first drum 4A in the region of said first passages 5A so as to scrape excess mass in said first passages 5A.

As described in US-4,279,579, preferably, the first circumferentially offset passages 4A are connected to each other by grooves arranged along the periphery of the first drum 4A.

As described in US-4,279,579, preferably, each groove extends in a spiral direction, each groove connecting openings which lie in parallel planes which are arranged perpendicular to the axis of the drum and which lie on different longitudinal imaginary lines extending along the periphery of said first drum.

The invention also relates to a device for extruding drops of a fluid mass onto a tread 6, said device comprising: a first cylindrical drum 4A comprising a plurality of first passages 5A, a second cylindrical drum 4B arranged inside said first drum 4A and comprising a plurality of second passages 5B, means 17 for admitting a fluid material into said second drum 4B, means for producing a relative rotation between said drums 4A, 4B, for periodically aligning said first passages 4A and second passages 4B, for depositing drops 7 of fluid material through the passages 4A, 4B, and onto the conveyor 6, said first and second drums 4A, 4B being mounted to separate radially from each other during said relative rotation so as to form a gap between said first and second drums 4A, 4B under negative pressure at a location opposite to the location where the passages are regularly aligned, so as to suck in the mass of excess material in said passages 5A of said first drum 4A, this device further comprising, as illustrated in Figure 1:

- a tank 11 equipped with heating means (not shown), and stirring means 13, making it possible to bring the container of the tank 11 to a fluid state,

- an injection channel, or several injection channels, 3 allowing the transfer of the fluid bitumen composition 2 inside the second drum 4B,

- a tank 14 into which an additive composition 15 can be introduced, the tank 14 being connected to the injection channel 3 via an injector 16 and allowing an injection of the additive composition 15 into the bitumen composition 2 at the channel 3, located downstream of the tank 11 and upstream of the double drum 4.

As described in US-4,279,579, preferably, said gap is formed by a recess in the periphery of the second drum 5B, the outer diameter of said recess being less than the inner diameter of said first drum 5A.

As described in US-4,279,579, preferably, the device comprises a spatula in contact with the periphery of the first drum to push excess material into the first passages 5A, said spatula being disposed in the region of said gap.

As described in US-4,279,579, preferably, the device comprises a tight fitting around the periphery of the cover of the first drum 4B to cover the area formed by the gap.

As described in US-4,279,579, preferably, the cover is bordered at its longitudinal ends by curved guide ribs having a contour corresponding to that of the first drum.

As described in US-4,279,579, preferably the guide strips include leading ends that are longitudinally inwardly beveled to direct excess material toward the spatula.

As described in US-4,279,579, preferably the first drum 4A is capable of rotation.

Examples

Materials and methods

The rheological and mechanical characteristics of the bitumens referred to in these examples are measured as indicated in Table 1.

Table 1

Property Abbreviation Unit Measurement standard Needle penetration at 25°C P25 1/10 mm NF EN 1426 Ring and ball softening temperature TBA °C NF EN 1427

The variation in the ring and ball softening temperature (RBT) is measured according to the NF EN 1427 standard of the said composition between the sample extracted from the upper part of the sample tube and the sample extracted from the lower part of the sample tube.

Experimental part:

Bitumen base B ₂ is prepared from:

- a bitumen base of grade 35/50, rated Bj, with a P25 penetrability of 34 1/10 mm and a TBA of 52.6°C and commercially available from the TOTAL group under the AZALT® brand;

- 1,10-decanedioic acid noted Additive Al.

The B3 bitumen base is prepared from:

- a grade 35/50 bitumen base, rated Bi, with a P25 penetrability of 34 1/10 mm and a TBA of 52.6°C and commercially available from the TOTAL group under the AZALT® brand;

- 1,10-decanedioic acid noted Additive Al.

- and N, N -ethylene-bis-stereamide, noted Additive A2.

I - Preparation of bitumen cores from solid bitumen granules

The quantities in mass percentage used for each bitumen are indicated in Table 2 below.

Table 2

Asphalt b ₂ b ₃ Bitumen base Bi 98.5% 96% Al Additive 1.5% 1.5% Additive A2 - 2.5% P25 (1/10 mm) 14 20 TBA (°C) 93 105.5

The bitumen is prepared in the following way.

For bitumen B2, the bitumen base Bi is introduced into a reactor maintained at 160°C with stirring at 300 rpm for two hours. The additive Al is then introduced into the reactor. The contents of the reactor are maintained at 160°C with stirring at 300 rpm for 1 hour.

For bitumen B3, the bitumen base Bi is introduced into a reactor maintained at 160°C with stirring at 300 rpm for two hours. Additive Al and additive A2 are then introduced into the reactor. The contents of the reactor are maintained at 160°C with stirring at 300 rpm for 1 hour.

In order to prepare the granule cores from the bituminous compositions described above, a device and a method are used as described in great detail in US patent 4,279,579. Different models of this device are commercially available from the Sandvik company under the trade name Rotoform.

The bituminous composition Bi, B2 or B3 is poured into the tank 11 of the device 1 and maintained at a temperature between 130 and 270°C.

One or more injection nozzles 3 allow(s) the transfer of the bitumen composition Bi, B2 or B3 inside the double pelletizing drum 4 comprising a rotating external drum, the two drums being equipped with slots, nozzles and orifices allowing the pelletizing of drops of bitumen 7 through the first fixed drum and the orifices 5 having a diameter of between 2 and 10 mm of the rotating external drum. Under the effect of the substantially homogeneous internal pressure inside the double drum 4 of the device 1, the drops 7 with a diameter between 2 and 10 mm are pelletized regularly through the orifices 5. The drops of bitumen 7 are deposited on the upper face 6A of a horizontal tread 6, driven by the rollers 12A and 12B, and one end of which is placed under the double drum 4. The tangential speed V _T of the double drum 4 is parallel to the tread 6 and in the same direction as the speed V _R of the tread 6 with V _R and V _T being substantially identical and having a speed Vt = 3 m/minute. The tread 6 with a length of 10 m and a width of 60 cm is equipped with four thermal conditioning devices 8 respectively on two sections SI and S2 comprising nozzles 8, 9 for vaporizing water, on the lower face 6B of the tread 6. The section SI conditions the tread 6 at ambient temperature (22-28°C), and the section S2 cools the tread to a temperature below 20°C. At the end of the tread opposite the double drum 4, the drops of bitumen 7 are transferred to receiving means 10 consisting of a storage device being “big bags”. Bitumen granules Gi, G2 and G3 were respectively obtained from the bituminous bases Bi, B ₂ and B ₃ and according to the method described above. These granules are solid at ambient temperature.

II - General method for the preparation of solid bitumen granules according to the invention comprising a coating layer

The bitumen granules obtained previously are left at room temperature for 10 to 15 minutes. The granules thus formed are coated on their surface with an anti-caking compound, then passed through a sieve to remove the excess anti-caking compound.

Bitumen granules Gi', G2' and G3' are prepared from bitumen granules Gi, _G2 and _G3 obtained previously and according to the method described above using pyrogenic silica as an anti-caking compound, commercially available under the reference AEROSIL®200.

The mass percentage of the coating for granules Gi', _G2 ' and G3' is approximately 1% by mass relative to the total mass of the bitumen in the granules.

III - Storage stability

Granule load resistance test:

This test is implemented in order to evaluate the load resistance of the bitumen granules prepared above at a temperature of 65°C under a compressive force. Indeed, this test makes it possible to simulate the temperature and compression conditions of the granules on each other to which they are subjected during transport and/or storage in bulk in bags of 10 to 100 kg or in Big Bags of 500 to 1000 kg or in drums of 200 kg and to evaluate their resistance under these conditions.

The load resistance test is carried out according to the following protocol: 5 mL of granules are placed in a 20 mL syringe then the piston is placed on the granules as well as a mass of 208g, representing a force applied as in a Big Bag. The whole is placed in an oven at 65°C for at least 4 hours. The observations are listed in Table 3 below.

Table 3

Granules Gj Gf g ₂ G ₂ ' G3 G ₃ ' Standard at room temperature at 65°C — - + ++ + +++

+++: the granules retain their initial shape and do not adhere to each other.

++: the granules do not adhere to each other but are slightly deformed.

+: the granules adhere slightly to each other.

- : the granules are partially melted.

—: the granules are melted.

The G ₂ 'and G3' granules have very good resistance to an ambient temperature of 60°C as they retain their initial shape and do not adhere to each other. Thus, the handling and transport/storage of said G ₂ 'and G3' granules will be easy as the granules do not melt and do not agglomerate with each other at high ambient temperature.

Claims (12)

66 CLAIMS 1. Method for manufacturing a material usable as a road binder or as a waterproofing binder, solid at room temperature in the form of granules comprising a core (7) based on a first composition (2) and optionally a coating layer based on a second composition, the first composition comprising at least one material chosen from: a bitumen base, a pitch, a clear binder, this method comprising the implementation of a device (1) intended for granulation which comprises at least two coaxial drums (4) and a horizontal tread (6): a fixed inner drum comprising at least one orifice and a rotating outer drum comprising a plurality of orifices (5), the drums being placed above one end of the horizontal tread (6), driven at a speed Vr, this method comprising at least: (i) heating the first composition to a temperature at which it is fluid, (ii) introducing the first composition (2) in the fluid state into the inner drum of the granulation device (1), (iii) distributing the first composition (2) outwards, in the form of drops (7) through the orifices (5) of the outer rotating drum, (iv) depositing the drops (7) on the tread (6), and (v) optionally coating the drops (7) with the second composition. 2. Method according to claim 1, which further comprises, after step (iv) between steps (iv) and (v), a step (iv') of cooling the drops (7) of the first composition (2). 3. Method according to claim 2, in which the cooling (iv') is carried out by means of a temperature gradient on the tread (6). 4. Method according to claim 3, in which the tread (6) is conditioned at different temperatures over several sections (SI), ...(Si) of its path, with i an integer ranging from 2 to 8, preferably from 2 to 4 by thermal conditioning means (8,9). 5. Method according to any one of the preceding claims, in which the rotating outer drum of the device (1) comprises orifices (5) with a diameter ranging from 2 to 10 mm, preferably from 2 to 8 mm, preferably from 3 to 7 mm, even better from 3.5 to 6 mm. 6. Method according to any one of the preceding claims, in which in step (i) the first composition (2) is brought to a temperature ranging from 100 to 270°C, preferably from 100 to 180°C, preferably from 120 to 160°C, even better from 130 to 150°C. 7. Method according to any one of the preceding claims, in which the speed Vr of the tread (6) is less than 4 m/min. 8. Method according to any one of the preceding claims, in which the material usable as a road binder or as a waterproofing binder is chosen from: a bitumen composition, a pitch, a clear binder, a bitumen/polymer stock solution, a clear binder/polymer stock solution. 9. Method according to any one of the preceding claims, in which the first composition comprises at least one material chosen from: a bitumen base, a pitch, a clear binder, a bitumen/polymer composition, a clear binder/polymer composition, a bitumen/polymer stock solution; a clear binder/polymer stock solution; a mixture of these materials. 10. Method according to any one of the preceding claims, in which the first composition (2) further comprises at least one chemical additive chosen from: an organic compound, a paraffin, a polyphosphoric acid and their mixtures. 11. Use of the method according to any one of the preceding claims for manufacturing a composition of material usable as a road binder or as a coating binder, solid at room temperature, which has stability during transport and storage at a temperature ranging from 20 to 80°C for a period greater than or equal to 2 months, preferably greater than or equal to 3 months. 12. Device usable for implementing a method according to any one of claims 1 to 11, which comprises at least: a first cylindrical drum (4A) arranged above the tread (6) and capable of rotation about a longitudinal axis (XX), said first drum (4A) comprising a plurality of first passages (5A) through the periphery of the drum (4A, a second cylindrical drum (4B) coaxial with the first drum (4A), comprising means (17) for longitudinally admitting into said second drum (4B) the mass to be extruded and comprising on a part of its wall (19) a plurality of second passages (5B) directed towards the tread (6) and radially aligned with said first passages (5A), said wall part (19) being arranged adjacent to said first drum (4A), said first drum (4A) being mounted to allow its continuous rotation through 360 ° about the longitudinal axis (X-X) relative said second drum (4B) such that relative rotation between said drums (4A) and (4B) sequentially produces misalignment and alignment of the first passages (5A) and second passages (5B) to allow the fluid mass to move radially outwardly through the aligned passages, (5A), (5B) and onto the tread (6A), said device further comprising: - a tank 11 equipped with heating means and stirring means (13), - an injection channel, or several injection channels (3) allowing the transfer of the composition contained in the reservoir (11) inside the second drum 4B through the admission means (17), this device being characterized in that it comprises: - a reservoir (14) into which an additive composition (15) can be introduced, the reservoir (14) being connected to the injection channel (3) via an injector (16) and allowing injection of the additive composition (15) into the bitumen composition (2) at the injection channel (3), located downstream of the reservoir (11) and upstream of the double drum (4).