EP0572648A1 - Procede de production d'une emulsion d'un liant bitumineux permettant le controle de la viscosite et des qualites de rupture de l'emulsion. - Google Patents
Procede de production d'une emulsion d'un liant bitumineux permettant le controle de la viscosite et des qualites de rupture de l'emulsion.Info
- Publication number
- EP0572648A1 EP0572648A1 EP93902354A EP93902354A EP0572648A1 EP 0572648 A1 EP0572648 A1 EP 0572648A1 EP 93902354 A EP93902354 A EP 93902354A EP 93902354 A EP93902354 A EP 93902354A EP 0572648 A1 EP0572648 A1 EP 0572648A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- emulsion
- bituminous binder
- aqueous phase
- bitumen
- polymer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000839 emulsion Substances 0.000 title claims abstract description 214
- 239000011230 binding agent Substances 0.000 title claims abstract description 114
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 21
- 239000010426 asphalt Substances 0.000 title claims description 75
- 238000012544 monitoring process Methods 0.000 title 1
- 239000008346 aqueous phase Substances 0.000 claims abstract description 64
- 238000000576 coating method Methods 0.000 claims abstract description 15
- 230000002093 peripheral effect Effects 0.000 claims abstract description 7
- 238000004078 waterproofing Methods 0.000 claims abstract description 4
- 229920000642 polymer Polymers 0.000 claims description 58
- 239000000203 mixture Substances 0.000 claims description 44
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 claims description 43
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 31
- 238000000034 method Methods 0.000 claims description 29
- 230000001804 emulsifying effect Effects 0.000 claims description 23
- KAKZBPTYRLMSJV-UHFFFAOYSA-N Butadiene Chemical compound C=CC=C KAKZBPTYRLMSJV-UHFFFAOYSA-N 0.000 claims description 18
- 239000003795 chemical substances by application Substances 0.000 claims description 17
- 239000007822 coupling agent Substances 0.000 claims description 17
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 15
- 230000015572 biosynthetic process Effects 0.000 claims description 13
- 238000009835 boiling Methods 0.000 claims description 13
- 230000008569 process Effects 0.000 claims description 13
- RRHGJUQNOFWUDK-UHFFFAOYSA-N Isoprene Chemical compound CC(=C)C=C RRHGJUQNOFWUDK-UHFFFAOYSA-N 0.000 claims description 12
- 229920001577 copolymer Polymers 0.000 claims description 12
- 239000011593 sulfur Substances 0.000 claims description 12
- 229910052717 sulfur Inorganic materials 0.000 claims description 12
- 238000004073 vulcanization Methods 0.000 claims description 9
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- 125000001183 hydrocarbyl group Chemical group 0.000 claims description 3
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- 238000006243 chemical reaction Methods 0.000 claims description 2
- YACLQRRMGMJLJV-UHFFFAOYSA-N chloroprene Chemical compound ClC(=C)C=C YACLQRRMGMJLJV-UHFFFAOYSA-N 0.000 claims description 2
- 230000008878 coupling Effects 0.000 claims 1
- 238000010168 coupling process Methods 0.000 claims 1
- 238000005859 coupling reaction Methods 0.000 claims 1
- 239000000463 material Substances 0.000 abstract 1
- 239000000084 colloidal system Substances 0.000 description 42
- 239000003995 emulsifying agent Substances 0.000 description 33
- 238000002360 preparation method Methods 0.000 description 24
- 125000002091 cationic group Chemical group 0.000 description 23
- 238000004945 emulsification Methods 0.000 description 23
- 125000000129 anionic group Chemical group 0.000 description 10
- 239000003921 oil Substances 0.000 description 10
- 229920005596 polymer binder Polymers 0.000 description 10
- 239000002491 polymer binding agent Substances 0.000 description 10
- 239000002253 acid Substances 0.000 description 9
- 230000000149 penetrating effect Effects 0.000 description 9
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- -1 polytetrafluoroethylene Polymers 0.000 description 8
- 229920001400 block copolymer Polymers 0.000 description 7
- 238000005192 partition Methods 0.000 description 7
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- 239000000047 product Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 229910052708 sodium Inorganic materials 0.000 description 6
- 239000011734 sodium Substances 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 238000003892 spreading Methods 0.000 description 6
- 230000007480 spreading Effects 0.000 description 6
- 238000003756 stirring Methods 0.000 description 6
- 239000000654 additive Substances 0.000 description 5
- 150000001412 amines Chemical class 0.000 description 5
- 239000010413 mother solution Substances 0.000 description 5
- 239000002243 precursor Substances 0.000 description 5
- 239000004576 sand Substances 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 4
- 229910052783 alkali metal Inorganic materials 0.000 description 4
- 150000001340 alkali metals Chemical class 0.000 description 4
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- 229930195733 hydrocarbon Natural products 0.000 description 4
- 150000002430 hydrocarbons Chemical class 0.000 description 4
- 239000004615 ingredient Substances 0.000 description 4
- 229910052500 inorganic mineral Inorganic materials 0.000 description 4
- 239000010410 layer Substances 0.000 description 4
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- 239000011707 mineral Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 230000035939 shock Effects 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 3
- 239000005977 Ethylene Substances 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 230000009471 action Effects 0.000 description 3
- 239000002585 base Substances 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 150000004985 diamines Chemical class 0.000 description 3
- 235000014113 dietary fatty acids Nutrition 0.000 description 3
- 229930195729 fatty acid Natural products 0.000 description 3
- 239000000194 fatty acid Substances 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 229910021645 metal ion Inorganic materials 0.000 description 3
- 239000003002 pH adjusting agent Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 239000003208 petroleum Substances 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- 238000007665 sagging Methods 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- 238000007711 solidification Methods 0.000 description 3
- 230000008023 solidification Effects 0.000 description 3
- JNYAEWCLZODPBN-JGWLITMVSA-N (2r,3r,4s)-2-[(1r)-1,2-dihydroxyethyl]oxolane-3,4-diol Chemical class OC[C@@H](O)[C@H]1OC[C@H](O)[C@H]1O JNYAEWCLZODPBN-JGWLITMVSA-N 0.000 description 2
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 description 2
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 description 2
- MTAZNLWOLGHBHU-UHFFFAOYSA-N butadiene-styrene rubber Chemical compound C=CC=C.C=CC1=CC=CC=C1 MTAZNLWOLGHBHU-UHFFFAOYSA-N 0.000 description 2
- 238000005056 compaction Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000004132 cross linking Methods 0.000 description 2
- 230000006837 decompression Effects 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 150000004665 fatty acids Chemical class 0.000 description 2
- 125000000524 functional group Chemical group 0.000 description 2
- 238000005470 impregnation Methods 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 229920000768 polyamine Polymers 0.000 description 2
- 239000005077 polysulfide Substances 0.000 description 2
- 150000008117 polysulfides Polymers 0.000 description 2
- 150000003242 quaternary ammonium salts Chemical class 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 229920006132 styrene block copolymer Polymers 0.000 description 2
- 239000003760 tallow Substances 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- 229920001897 terpolymer Polymers 0.000 description 2
- QBIAZVPERXOGAL-OWOJBTEDSA-N (e)-prop-1-ene-1,3-diamine Chemical compound NC\C=C\N QBIAZVPERXOGAL-OWOJBTEDSA-N 0.000 description 1
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- 229920002943 EPDM rubber Polymers 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 229920002367 Polyisobutene Polymers 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 206010057362 Underdose Diseases 0.000 description 1
- 235000011054 acetic acid Nutrition 0.000 description 1
- 239000011149 active material Substances 0.000 description 1
- 239000002318 adhesion promoter Substances 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 150000001447 alkali salts Chemical class 0.000 description 1
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 description 1
- 150000001336 alkenes Chemical class 0.000 description 1
- 150000008051 alkyl sulfates Chemical class 0.000 description 1
- 229940045714 alkyl sulfonate alkylating agent Drugs 0.000 description 1
- 125000003368 amide group Chemical group 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 150000003863 ammonium salts Chemical class 0.000 description 1
- 239000012874 anionic emulsifier Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 229920005549 butyl rubber Polymers 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- HQQADJVZYDDRJT-UHFFFAOYSA-N ethene;prop-1-ene Chemical group C=C.CC=C HQQADJVZYDDRJT-UHFFFAOYSA-N 0.000 description 1
- 150000002191 fatty alcohols Chemical class 0.000 description 1
- 150000002193 fatty amides Chemical class 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 235000011187 glycerol Nutrition 0.000 description 1
- 239000011440 grout Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- MTNDZQHUAFNZQY-UHFFFAOYSA-N imidazoline Chemical class C1CN=CN1 MTNDZQHUAFNZQY-UHFFFAOYSA-N 0.000 description 1
- 150000002462 imidazolines Chemical class 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 238000002356 laser light scattering Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 239000010742 number 1 fuel oil Substances 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 229920000636 poly(norbornene) polymer Polymers 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920001083 polybutene Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920001195 polyisoprene Polymers 0.000 description 1
- 229920000193 polymethacrylate Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 230000000135 prohibitive effect Effects 0.000 description 1
- 229920005604 random copolymer Polymers 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 229920005573 silicon-containing polymer Polymers 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 229920005552 sodium lignosulfonate Polymers 0.000 description 1
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- 239000011550 stock solution Substances 0.000 description 1
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- 229920000428 triblock copolymer Polymers 0.000 description 1
- 235000013311 vegetables Nutrition 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
- B01F27/60—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a horizontal or inclined axis
- B01F27/625—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a horizontal or inclined axis the receptacle being divided into compartments, e.g. with porous divisions
Definitions
- the invention relates to a process for producing an aqueous emulsion of a bituminous binder allowing the viscosity and the breaking qualities of said emulsion to be controlled.
- aqueous emulsions of bituminous binders in the construction and repair of roads, for paving roads, stabilizing the ground, making waterproofing in civil engineering or in buildings or for similar applications is well known.
- the aqueous solutions suitable for these applications are "oil in water" emulsions, which consist of a dispersion of an organic phase formed from fine globules of the bituminous binder in a continuous aqueous phase, said aqueous phase containing a system.
- emulsifier which promotes the dispersion of the globules of the bituminous binder in the aqueous phase and consists of one or more emulsifying agents, and optionally a pH regulating agent, which can be, as the case may be, an acid, a water-soluble salt or a base.
- Such emulsions are usually classified according to the nature of the emulsifying system used to ensure the dispersion of the bituminous binder in the aqueous phase and according to whether said emulsifying system is constituted of one or more anionic, cationic, nonionic or amphoteric emulsifying agents, the corresponding emulsions will be called anionic, cationic, nonionic or amphoteric respectively.
- the aqueous emulsion of the bituminous binder is considered to be a convenient means making it possible to reduce the apparent viscosity of said binder during the operations for using this bituminous binder. After rupture, the emulsion restores the bituminous binder added with part of the emulsifying system and other additives present in the aqueous phase.
- aqueous emulsions of bituminous binders used for producing impregnation layers, bonding layers or even surface coatings require completely different viscosity levels according to the use concerned.
- the emulsion must have a sufficiently low viscosity to be able to penetrate as deeply as possible into the structure to be stabilized before the emulsion breaks, resulting in the release of the binder.
- the emulsion In the case of a bonding layer or a surface coating, the emulsion must on the contrary have a sufficiently high viscosity so that the slope of the ground, on which this emulsion is spread, does not cause the formation of sagging , which have the double disadvantage of simultaneously causing local underdoses by binding bituminous and an overdose or soiling in other places.
- Increasing the viscosity of the emulsions is the solution generally adapted to minimize the problems of sagging.
- Said increase in viscosity can be carried out either by adding thickening products in the aqueous phase, or by adjusting the manufacturing parameters of the emulsion to control the average size and the particle size distribution of the bituminous binder globules which it contains, or else through an increase in the binder content of the emulsion.
- the aqueous emulsion at 80% by weight or more of bituminous binder must make it possible to solve the problems of sagging at conventional dosages and for uses requiring a higher dosage of emulsion as is the case, for example, for monolayer coatings.
- bituminous binder 80% by weight or more of bituminous binder also has an economic advantage, since it makes it possible to transport more active material (bituminous binder) for the same amount of emulsion, this aspect playing favorably to reduce transport costs to the site.
- the emulsification of hydrocarbon binders is generally carried out by bringing an emulsion enclosure of the colloid mill or turbine type, on the one hand, a bituminous binder in the form of a melt having a temperature between 80 ° C and 180 ° C and preferably between 110 ° C and 160 ° C and, on the other hand, an aqueous phase containing an emulsifying system or at least one of its components, the complement being present in the bituminous binder, and optionally an agent regulating the pH of the emulsion and having a temperature between 10 ° C and 90 ° C and preferably between 20 ° C and 80 ° C and the assembly is kept in said enclosure for a sufficient time to form the emulsion.
- the emulsion forming chambers of the colloid mill or turbine type used for emulsifying bituminous binders are for the most part rotor / stator devices of the cone / cone type or discs / discs with smooth or grooved surfaces.
- the rotor (mobile part of the device) and the stator (fixed part of the device) are separated by a very narrow air gap, namely between a few tenths of a millimeter and a few millimeters, which ensures the shearing and causes the dispersion of the bituminous binder in the form of globules separated in the continuous medium consisting of the aqueous phase.
- bituminous binders consisting of bitumens modified by polymers and in particular in bitumens modified by in-situ crosslinking of styrene / butadiene / styrene block copolymers
- the use of emulsification devices of the type above leads to the production of emulsions having too low viscosities and it is necessary to make certain adjustments in the internal architecture of said devices to remedy this drawback.
- the rotor and the stator generally covered with grooves or completely devoid of roughness on their surface, said devices have been replaced by rotors and stators having these two characteristics, such an architecture being said to have non-emerging grooves.
- aqueous emulsions containing 80% by weight or more of bituminous binder by using such emulsifying devices leads to a very fine particle size distribution of the bituminous binder globules dispersed in the continuous aqueous phase. , which results in a very high viscosity of the emulsion produced. This increase in viscosity leads to progressive blockage of the tubular exchangers during the production of such emulsions. Indeed, emulsions with 80% by weight or more of bituminous binder must be produced at a temperature above 100 ° C.
- bituminous binder in particular 80% and more
- bituminous binder in particular 80% and more
- bituminous binder at a lower temperature makes it possible to substantially increase the viscosity of an aqueous emulsion which would be too fluid under the usual production conditions, as is the case in particular for aqueous emulsions of which the bituminous binder content is between 60% and 75% by weight.
- an aqueous emulsion obtained from a bitumen or a modified bitumen by crosslinking in situ of a styrene / butadiene / styrene block copolymer exhibits a particle size distribution of the bituminous binder globules having an average size substantially greater than that of an aqueous emulsion obtained under analogous conditions with an emulsion forming enclosure of the cone / cone or disc / disc type.
- Another advantage of the use of the particular emulsion-forming enclosure according to the invention is that it leads to the production of aqueous emulsions of bituminous binder having a much more frank rupture without trapping water in it. inside the bituminous binder.
- bituminous binder behaves exactly as an emulsion with 70% by weight of binder would behave.
- bituminous which during its rupture would have already lost 10 water points due to the evaporation of the latter during the spreading of the emulsion.
- the process according to the invention for producing an aqueous emulsion of a bituminous binder allowing the viscosity and the breaking qualities of the emulsion to be controlled is of the type in which one operates in an emulsion forming chamber having an inlet and an outlet separated by a plurality of shear zones of the rotor / stator type arranged in series and each consisting of at least one circular groove formed in one face of a fixed element, integral with the wall of the enclosure, and playing the role of stator, and into which a plurality of lugs penetrate each having, in section through a plane containing the axis of the groove, a shape complementary to that of the corresponding section of said groove, so as to define between each lug and the groove a space forming an air gap, said lugs being integral with one of the faces of a support disc playing the role of rotor centered on the axis of the groove and movable in rotation a around said axis, which disc is traversed by orifices
- bituminous binder and the aqueous phase are premixed before passing into the first shear zone of the emulsion formation enclosure.
- the respective amounts of bituminous binder and of aqueous phase used to form the emulsion are advantageously such that the ratio of the mass flow rate of the bituminous binder to the mass flow rate of the aqueous phase, which are brought to the premixture or injected simultaneously and separately into the enclosure emulsion formation, is from 50:50 to 90:10 and preferably from 55:45 to 85:15.
- the channels connecting the respective bottoms of the consecutive grooves, which are formed in the opposite faces of the same stator element have a section having a surface greater than that of the orifices passing through the pin-bearing disc associated with each groove.
- the use of the emulsion forming enclosure according to the invention makes it possible to adjust the viscosity of an emulsion at a given concentration of bituminous binder produced by said enclosure, by simple adjustment of the value, chosen in the intervals defined above. , the temperature of the bituminous binder and of the aqueous phase, or of their premix, at the entrance to this enclosure, the viscosity of the emulsion being all the higher, all the other conditions being equal, as said inlet temperature is lower.
- the bituminous binder which is put in aqueous emulsion by the process according to the invention has a kinematic viscosity at 100 ° C. advantageously between
- Said bituminous binder may consist of a bitumen or of a mixture of bitumens having a kinematic viscosity included in the abovementioned intervals, which bitumen or mixture of bitumens may be chosen from bitumens for direct distillation or distillation under reduced pressure or even from bitumens blown or semi-blown, or even among certain petroleum fractions or mixtures of bitumens and distillates under vacuum.
- the bituminous binder usable according to the invention can also consist of a composition of the bitumen / polymer type, which composition can be any one of the products obtained from bitumens added with one or more polymers, and optionally modified by reaction with this.
- the amount of polymer generally represents 0.5% to 15% and preferably 0.7% to 10% of the weight of bitumen.
- the polymers which may be present in the bitumen / polymer composition can be chosen from the various polymers which are combined with bitumens in the bitumen / polymer compositions.
- Said polymers can be, for example, elastomers such as polyisoprene, butyl rubber, polybutene, polyisobutene, polyacrylates, polymethacrylates, polynorbornene, ethylene / propylene copolymers, ethylene / propylene / diene terpolymers (EPDM terpolymers), or also fluorinated polymers such as polytetrafluoroethylene, silicone polymers such as polysiloxanes, copolymers of olefins and monomers vinyl such as ethylene / vinyl acetate copolymers, ethylene / acrylic ester copolymers, ethylene / vinyl chloride copolymers, polymers of the polyvinyl alcohol, polyamide, polyester or even polyurethane type.
- elastomers such as polyisoprene, butyl rubber, polybutene, polyisobutene, polyacrylates, polymethacrylates, polynorbornene,
- the polymer present in the bitumen / polymer composition is chosen from random or block copolymers of styrene and of a conjugated diene because these copolymers dissolve very easily in bitumens and give them excellent mechanical and dynamic properties. and in particular very good viscoelastic properties.
- the copolymer of styrene and a conjugated diene is chosen from block copolymers of styrene and butadiene, styrene and isoprene, styrene and chloroprene, styrene and carboxylated butadiene or styrene and carboxylated isoprene.
- the copolymer of styrene and of conjugated diene and in particular each of the abovementioned block copolymers advantageously has a weight content of styrene ranging from 5% to 50% by weight.
- the average viscosimetric molecular weight of the copolymer of styrene and of conjugated diene and in particular that of the copolymers mentioned above can be, for example, between 10,000 and 600,000 and is preferably between 30,000 and 400,000.
- the styrene copolymer and of conjugated diene is chosen from di- or triblock copolymers of styrene and butadiene, styrene and isoprene, styrene and carboxylated butadiene or alternatively styrene and carboxylated isoprene, which have styrene and molecular weights located in the ranges defined above.
- the bitumen / polymer composition may also contain 1 to 40% and more particularly 2 to 20%, by weight of the bitumen, of a fluxing agent, which may consist, in particular, of a hydrocarbon oil having a distillation range at atmospheric pressure, determined according to standard ASTM D 86-67, between 100 ° C and 450 ° C and more especially located between 150 "C and 380 ° C.
- a hydrocarbon oil can be, for example, a petroleum cut of aromatic character, an oil cut of naphtheno-aromatic character, an oil cut of naphtheno-paraffinic character, an oil cut of paraffinic character, a coal oil or an oil of vegetable origin.
- bitumen / polymer composition having the required viscosity can be obtained by simple mixing of the appropriate quantity of elastomeric polymer included in the range defined above, with the bitumen chosen, for its part, to have a viscosity compatible with the viscosity of the composition. bitumen / polymer to be produced.
- the bitumen / polymer composition can also be produced by first mixing the polymer with the bitumen as indicated above, then by incorporating into said mixture a sulfur-donating coupling agent in a quantity suitable for providing a quantity of elemental or radical sulfur. representing 0.5% to 10% and more particularly 1% to 8% of the weight of the polymer used to produce the bitumen / polymer composition and maintaining the whole with stirring at a temperature between 100 ° C and 230 ° C, for example corresponding to the temperature of contact of the polymer with the bitumen, for a sufficient time to form a bitumen / polymer composition having the desired viscosity and for which the polymer is attached to the bitumen.
- the sulfur donor coupling agent can be chosen, in particular, from elementary sulfur, hydrocarbyl polysulfides as described in the citation F -A-2528439 and the vulcanization systems containing vulcanization accelerators as described in the citation EP-A-0360656.
- bitumen / polymer composition containing a fluxing agent When a bitumen / polymer composition containing a fluxing agent is used, the latter can be added to the medium which, as indicated above, is formed from bitumen, polymer and optionally the coupling agent, to a any time when said medium is formed, the quantity of fluxing agent being chosen to be compatible with the desired end use on the site.
- the polymer and said coupling agent are incorporated into the bitumen in the form of a mother solution of these products in the fluxing agent and in particular in the oil hydrocarbon defined above as capable of constituting the fluxing agent.
- the mother solution can be prepared by bringing the component ingredients, namely fluxing agent, polymer and coupling agent, into contact at temperatures between 10 ° C. and 140 ° C. and for a time sufficient to obtain complete dissolution of the polymer and of the coupling agent in the fluxing agent.
- the respective concentrations of the polymer and of the coupling agent in the mother solution can vary quite widely depending in particular on the nature of the fluxing agent used to dissolve the polymer and the coupling agent.
- bitumen / polymer composition using the mother solution, the mother solution of the polymer and of the coupling agent in the fluxing agent is mixed with the bitumen in the molten state, with stirring, then the resulting mixture is maintained. , in the molten state and with stirring, for a sufficient time to obtain a fluid product of continuous appearance and viscosity compatible with the final use on the site.
- the bitumen / polymer composition may also contain various additives and in particular nitrogen-containing compounds of the amine or aids type as adhesion promoters of the bitumen / final polymer binder to mineral surfaces, said nitrogen-containing compounds preferably being grafted onto the bitumen / polymer component and in particular on the polymer chains of said composition.
- the bituminous binder of the bitumen / polymer composition type can also be added with a sulfur-donor vulcanization system, or the case if necessary, components of such a system forming said system in situ, in a concentration suitable for supplying an amount of sulfur representing 0.5 to 20% and preferably 1 to 15% of the weight of the polymer present in the bitumen / polymer composition.
- the sulfur donor vulcanization system can be chosen, among others, from the products indicated above as capable of constituting the coupling agent used to produce certain bitumen / polymer compositions.
- the aqueous phase which is used in the implementation of the process according to the invention, consists of water containing an emulsifying system in an effective amount, that is to say in an amount suitable for dispersing the globules of the binder bituminous in said aqueous phase and to prevent the re-agglomeration of said dispersed globules.
- the amount of emulsifying system is generally chosen to represent 0.05% to 5% and preferably 0.1% to 2% of the total weight of the emulsion.
- the emulsifying system present in the aqueous phase of the emulsion can be cationic, anionic, nonionic or even amphoteric in nature.
- An emulsifying system of a cationic nature which gives rise to a cationic emulsion, comprises one or more cationic emulsifying agents which can advantageously be chosen from nitrogenous cationic emulsifying agents such as fatty monoamines, polyamines, idoamines, amidopolyamines, salts or oxides of said amines and amidoamines, reaction products of the above-mentioned compounds with ethylene oxide and / or propylene oxide, imidazolines and quaternary ammonium salts.
- nitrogenous cationic emulsifying agents such as fatty monoamines, polyamines, idoamines, amidopolyamines, salts or oxides of said amines and amidoamines, reaction products of the above-mentioned compounds with ethylene oxide and / or propylene oxide, imidazolines and quaternary ammonium salts.
- the emulsifying system of a cationic nature can be formed by the association of one or more cationic emulsifying agents A chosen from cationic nitrogen emulsifying agents of the types of monoamines, dia ines, amidoamines, oxides of such amines or amidoamines, reaction products of such compounds with ethylene oxide and / or propylene oxide and quaternary ammonium salts, with one or more agents emulsifiers B chosen from cationic nitrogen emulsifiers having in their molecule at least three functional groups chosen from amine and amide groups such that at least one of said functional groups is an amino group, the ratio of the weight amount of the or of compounds A to the total weight amount of compounds A and B ranging in particular from 5% to 95%.
- A chosen from cationic nitrogen emulsifying agents of the types of monoamines, dia ines, amidoamines, oxides of such amines or amidoamines, reaction products of such compounds with ethylene oxide and / or prop
- An anionic emulsifier system which gives rise to an emulsion • anionic, comprises one or more anionic emulsifying agents which may be chosen in particular from alkali metal or ammonium salts of fatty acids, alkali metal polyalcoxycarboxylates , the alkali metal N-acylsarcosinates, the alkali metal hydrocarbylsulfonates and in particular the sodium alkylsulfonates, sodium arylsulfonates and sodium alkylaryl sulfonates, sodium alkylene sulfonates, sodium lignosulfonates and sodium alkyl sulfates sodium.
- anionic emulsifying agents which may be chosen in particular from alkali metal or ammonium salts of fatty acids, alkali metal polyalcoxycarboxylates , the alkali metal N-acylsarcosinates, the alkali metal hydrocarbylsulfonates and in particular the sodium alkyls
- an emulsifying system of a nonionic nature formed from one or more nonionic emulsifying agents which can in particular be chosen from ethoxylated fatty alcohols, ethoxylated fatty acids, sorbitan esters, ethoxylated sorbitan esters, ethoxylated alkylphenols, ethoxylated fatty amides and fatty acid esters of glycerin.
- an emulsifying system of amphoteric nature formed by one or more amphoteric emulsifying agents which can be chosen, for example, from betaines and amphoteric imidazolinium derivatives.
- an emulsifying system consisting of a mixture of emulsifying agents of different natures, for example a mixture of one or more anionic or cationic emulsifying agents with one or more nonionic or / and amphoteric emulsifying agents.
- KIRK-OTHMER entitled ENCYCLOPEDIA OF CHEMICAL TECHNOLOGY, Third Edition, Volume 22, pages 347 to 360 (anionic emulsifiers), pages 360 to 377 (nonionic emulsifiers), pages 377 to 384 (cationic emulsifiers) and pages 384 to 387 (amphoteric emulsifiers).
- an agent intended to adjust the pH of the emulsion to the desired value can be an acid, for example a mineral acid such as HC1, HN0 3 , H 3 PO4 or a saturated or unsaturated mono- or polycarboxylic acid such as acetic acid, formic acid, oxalic acid or l citric acid, when the pH value of the emulsion must be lowered, or a base or a basic salt, in particular a mineral base consisting of an alkali metal hydroxide such as sodium hydroxide or an alkaline earth oxide or hydroxide, when the pH value of the emulsion must be increased.
- a mineral acid such as HC1, HN0 3 , H 3 PO4 or a saturated or unsaturated mono- or polycarboxylic acid such as acetic acid, formic acid, oxalic acid or l citric acid
- a base or a basic salt in particular a mineral base consisting of an alkali metal hydroxide such as sodium hydroxide or an
- the aqueous phase may also contain various additives such as, for example, metal ion complexing agents as described in the citations FR-A-2577545 and FR- A-2577546.
- the emulsifying system and the other optional ingredients, including pH adjusting agent and complexing agent are incorporated.
- the quantity of water necessary for the production of the desired emulsion which quantity of water is brought beforehand to a temperature between 10 ° C and 90 ° C and preferably between 20 "C and 80" C.
- the amount of emulsifier system added to the water is chosen so that the concentration of said emulsifier system in the final emulsion is within the range defined above.
- other ingredients in particular a pH adjusting agent, a metal ion complexing agent or the like, must be incorporated into the aqueous phase, the respective amounts of said ingredients are those commonly used for this purpose.
- the aqueous phase for producing an anionic emulsion can be prepared as follows. In water, maintained at a temperature between 10 "C and 90 ° C and more particularly between 20 ° C and 80 ° C, dissolving or dispersing, while operating with stirring, the appropriate quantity of an emulsifier precursor of the anionic type consisting of an acid or polyacid with a saturated aliphatic chain or partially unsaturated or also partially cyclic. A concentrated solution of NaOH or KOH is then added to the obtained solution or suspension until neutralization of the acid and formation of the corresponding salt which is the emulsifying agent • anionic.
- the pH of the emulsion can range between 7 and 13 and more especially between 9 and 11.
- the concentration of acid precursor of the aqueous phase is chosen to represent between 0.02% and 2% of the weight of the final emulsion depending on the use of the emulsion on the road.
- the aqueous phase can, for example, be prepared as follows.
- cationic emulsifying agents for example of the type of fatty amines or fatty chain polyethylene polyamines
- a sufficient amount of a mineral acid or an organic monocarboxylic or polycarboxylic acid is added to the dispersion thus obtained to obtain a final pH of between 1 and 7 and preferably between 2 and 5.
- concentration of cationic emulsifying agent (s) in the aqueous phase is chosen to represent 0.2 to 2% of the weight of the final cationic emulsion.
- additives such as metal ion complexing agents, tackifiers or the like are used, these additives are added to the aqueous phase to a any time in the preparation of the latter and in any order.
- the bituminous binder is at a temperature, which leads, after contact with the aqueous phase, to a temperature higher than the boiling temperature of water, the circuit must be maintained under pressure sufficient to prevent boiling of water.
- the emulsion discharged from the emulsion forming chamber must be cooled, for example in an air or water heat exchanger, to a temperature below 100 ° C. before being brought back to atmospheric pressure. to be sent to final storage or to be loaded directly into a spreading truck.
- bituminous binder emulsion obtained by the process according to the invention can be used for the production of coatings and in particular road coatings of the surface coating type, for the production of hot or cold mixes, or even for the waterproofing coatings.
- an emulsifier is chosen as the emulsifier for the aqueous phase, allowing rapid breaking of the emulsion, which results in the restitution of a bituminous binder adhering to both the pavement and the aggregates.
- the final goal of using the emulsion is the installation of a mix, it can be operated either cold by spreading using a finisher of the aggregate / emulsion mixture prepared in the coating plant, followed by compaction of said mixture by smooth rollers or / t by pneumatic compactors, either hot by kneading the emulsion with hot aggregates until complete evaporation of the water, followed by spreading using a asphalt paver prepared in a asphalt mixing plant, then compaction of said asphalt by smooth rollers and / or pneumatic compactors.
- the emulsion obtained by the process according to the invention can also be introduced hot into a coating plant where the previously heated and dried aggregates are kneaded with said emulsion, which results in
- the emulsion prepared by the process according to the invention can also be used in the technique of cold-cast mixes.
- the composition of the phase aqueous is suitable, as is known in the art, to allow the grout to rupture after it has been kneaded and spread on the floor.
- Figure 1 shows a schematic longitudinal section of an emulsion forming enclosure according to the invention with integrated premixer, while Figures la and lb show the opposite faces of a rotor disc provided with lugs and l 'groove stator element which form a shear zone of said enclosure; and
- FIGS. 2a and 2b schematically show a variant of the facing faces of a rotor disc provided with lugs
- Figure 2a and the associated groove stator element (Figure 2b), which form a shear zone of the emulsion-forming enclosure, while Figures 2c and 2d are sections by a radial plane respectively of said rotor and said stator element.
- the emulsion forming enclosure according to the invention with integrated premixer which is shown diagrammatically in FIGS. 1, 1a and 1b, is formed by a chamber 1 delimited by a cylindrical side wall 2 having a front end closed by a wall 3 and a rear end closed by a wall 4.
- the wall 3 is provided with a conduit 5 forming an inlet conduit, which opens in the chamber 1 by one of its ends 6 and divides at its another end 7 in two conduits, namely a conduit 8 for supplying a bituminous binder in the molten state and a conduit 9 for supplying an aqueous phase.
- the chamber 1 is provided with a conduit 10 forming an outlet conduit and arranged to open out radially or tangentially into said chamber.
- Chamber 1 is divided into compartments, here four in number 11 to 14, by partitions, here in number three numbered 15 to 17, said partitions, of identical structures, being integral with the side wall 2 of chamber 1 and being each delimited by two parallel flat faces which are perpendicular to the longitudinal axis 18 of the cylindrical chamber 1, namely faces 19 and 20 for the partition 15, faces 21 and 22 for the partition 16 and faces 23 and 24 for the partition 17 , said partitions 15 to 17 playing the role of .stators elements.
- the partitions 15 to 17 are arranged so in the chamber 1 that the extreme compartments 11 and 14 have a sufficient width to respectively constitute a compartment 11 of premix for the precursors of the emulsion which are the bituminous binder and the aqueous phase and a compartment 14 for collecting the emulsion and that the intermediate compartments 12 and 13 have a very small width.
- the inlet conduit 5 opens into the premix compartment 11, while the outlet conduit 10 opens into the compartment 14 for collecting the emulsion.
- a circular groove of axis coinciding with the longitudinal axis 18 of the chamber 1 is practiced, namely grooves 28 and 29 respectively for the faces 19 and 20 of the stator element 15, grooves 30 and 31 for the faces 21 and 22 of the stator element 16 and grooves 32 and 33 for the faces 23 and 24 of the stator element 17, said grooves having the same mean diameter, width and depth.
- the grooves belonging to the same stator element are connected, bottom to bottom, by channels formed in said stator element, namely channels 34 for the stator element 15, channels 35 for the stator element 16 and channels 36 for the element stator 17.
- a series of lug-shaped lugs penetrate into each of the grooves, namely series 37 to 42 corresponding respectively to grooves 28 to 33.
- the fins associated with each groove for example fins of the series 37 associated with the groove 28 as indicated in FIG. 1 a, each in this example, in section by a plane perpendicular to the axis of the groove, has a trapezoid shape with curvilinear parallel sides 43 and 44 concentric with the side walls 45 and 46 of the associated groove and, in section through a median plane containing the axis of the groove, a shape complementary to the section of said groove by this plane so as to define between each fin and the groove an air gap space having a thickness located in the intervals defined above.
- the fins of the same series of fins are integral with one of the parallel faces of a support disc playing the role of rotor element.
- the different series of fins 37 to 42 are carried, in the diagram shown, by four discs 47 to 50, namely disc 47 located in the compartment 11 and carrying on one side the series of fins 37 penetrating into the groove 28 formed in the face 19 of the stator element 15, disc 48 located in the intermediate compartment 12 and carrying, on one of its faces, the series of fins 38 penetrating into the groove 29 formed in the face 20 of the element stator 15 and, on the other face, the series of fins 39 penetrating into the groove 30 formed in the face 21 of the stator element 16, disc 49 located in the intermediate compartment 13 and bearing, on one of its faces, the series of fins 40 penetrating into the groove 31 formed in the face 22 of the stator element 16 and, on the other face, the series of fins 41 penetrating into the groove 32 formed in the face 23 of the stator element 17 and finally disc 50 located in the compartment 14 for collecting the emulsion and carrying on a single face the series of fins 42 penetrating into the groove 33 formed in the face 24
- Each disc which has an axis coinciding with the axis 18 of chamber 1 so that its parallel faces are parallel to the faces of the associated stator element, is mounted, for example by a keying system not shown, on the shaft 25 so as to be integral with the latter and this made to be driven in rotation by said shaft when the latter is rotated by the motor 26.
- Each disc is traversed by orifices made in the disc between the shaft 25 and the series or fins of fins carried by the disc, namely orifices 51 for the disc 47, orifices 52 for the disc 48, orifices 53 for the disc 49 and orifices 54 for the disc 50, said orifices advantageously having a section whose surface is less than the section of the channels formed in the stator elements for- connect, bottom to bottom, the two grooves that each stator element has.
- the discs 47 to 50 have a slightly smaller diameter, for example 0.2mm to 1mm less, than the inside diameter of the cylindrical chamber 1.
- each grooved face of any one of the stator elements 15 to 17 is separated from the opposite face of the associated disc provided with fins penetrating into the groove, through a space having a small thickness, for example a thickness ranging from 0.1mm to 5mm and preferably from 0.2mm to 2mm.
- the thickness of each of the compartments 12 and 13 is therefore slightly greater, for example greater by 0.2mm to 10mm and preferably from 0.4mm to 4mm, than the thickness of the disc present in the compartment concerned.
- the space between the grooved face of any one of the stator elements 15 to 17 and the opposite face of the associated disc provided with fins penetrating into the groove thus defines a shear zone.
- the grooves of two consecutive shear zones are either formed in the opposite faces of the same stator element and connected by channels connecting their respective bottoms, or formed in the opposite faces of two consecutive stator elements and then separated by a perforated disc through which they communicate.
- FIGS. 1 shows diagrammatically in FIGS.
- each of the faces of any one of the stator elements 15 to 17 is provided with two concentric grooves, so that each groove has on one of the faces of any stator element corresponds an identical groove on the other face of this element, these corresponding grooves being connected, bottom to bottom, by channels made in said stator element and, on the other hand, each face of any disc 47 to 50, which is opposite a doubly grooved face of a stator element 15 to 17, carries two concentric series of lugs, for example cylindrical, so that the lugs of a series penetrate into one of the grooves of the doubly grooved face so as to define with this groove a space playing the role of air gap as indicated in the case of the fins of the system of FIG. 1.
- each of the faces 21 and 22 of the stator element 16 are provided with two concentric grooves 55 and 56 on the face 21 and two corresponding concentric grooves 57 and 58 on the face 22, the grooves 55 and 57 being connected ected, bottom to bottom, by channels 59 and the grooves 56 and 58 being connected, bottom to bottom, by channels 60, which channels 59 and 60 are formed in said stator element 16, while, for example, as shown schematically on FIGS.
- one of the faces of the disc 48 forming a rotor element and crossed by the orifices 52, is provided with two concentric series of cylindrical pins 61 and 62, the first penetrating into the groove 55 of the element stator 16 and the latter in the groove 56 of said element, and the other face of the disc 48 is also provided with two concentric series 63 and 64 of cylindrical lugs arranged to correspond to two grooves formed in the face 20 of the stator element 15.
- the emulsion formation chamber with integrated premixer described above operates as follows.
- the precursors of the aqueous emulsion namely bituminous binder in the molten state and aqueous phase, brought respectively by the conduits 8 and 9 then by the conduit 5, penetrate into the compartment 11 in which the said precursors are subjected to the action of the agitator element driven in rotation by the shaft 25 mu by the motor 26 and are thus premixed.
- the premix thus produced then passes through the successive shear zones, which are each formed by the space between the grooved face of a stator element and the face provided with facing lugs belonging to the associated rotor element and which are connected in series either through the orifices passing through a rotor element, or through the channels connecting, by their respective bottoms, the opposite grooves of the same stator element.
- the medium formed by the bituminous binder in the molten state and the aqueous phase is subjected to the action of shear forces created by the rotation of the rotor element driven by the shaft driven by the motor 26 and by the displacement resulting from the lugs integral with the rotor element in the associated groove of the stator element, which contributes to dividing the bituminous binder into globules and to dispersing these globules in the aqueous phase to produce the emulsion .
- the emulsion produced leaves the last shear zone through the orifices 54 of the last rotor element 48 and ends up in the collection compartment 14, from which it is continuously discharged through the outlet conduit 10 to be directed towards a zone storage or to a point of use.
- Two cationic emulsions were prepared, namely a control emulsion A and an emulsion B according to the invention, at 80% by weight of a bituminous binder of the bitumen / polymer type consisting of the reaction product at high temperature of a road bitumen of 80/100 penetration with a stock solution consisting of a solution of sulfur and of a block copolymer of styrene and butadiene containing, by weight 25% of styrene and 75% of butadiene in an oil cut obtained in a refinery and called "Light Cycle Oil", said cut having a distillation interval of the order of 180 ° C to 360 ° C.
- bituminous binder 247 parts by weight of the block copolymer were dissolved in 745 parts of the petroleum cut by operating at a temperature between 80 ° C and 100 ° C. After complete dissolution of the polymer, 8 parts of sulfur were added to the solution. Eleven parts of the solution thus prepared were mixed with 89 parts of road bitumen and the mixture was brought to a temperature between 170 ° C and 180 "C for about 1.5 hours. This gave a bituminous bitumen / polymer binder whose main characteristics are indicated below: Viscosity at 160 ° C: 110 mPa.s
- a conventional colloid mill consisting of a concentric frustoconical stator and rotor having a large diameter equal to 50mm and an air gap (space between the lateral surfaces facing the rotor and the stator) having a thickness of 0.3mm
- 800 parts of the bituminous bitumen / polymer binder were introduced continuously at 160 ° C. and 200 parts of aqueous phase at 60 ° C, with an overall flow of 150kg / hour.
- the emulsification mill was kept under pressure to prevent boiling of the water from the medium subjected to the emulsification, the temperature of which was about 125 "C. and the speed of rotation of the rotor was fixed at 6000 revolutions / minute. , which corresponds to a peripheral speed of the rotor of around 15m / s.
- emulsion B The operation was carried out in a colloid mill similar to that shown diagrammatically in FIG. 1 and for which, in operation, the shaft 25 was driven by the motor 26 with a rotational speed of 3600 revolutions / minute, which communicated to each of the rotor elements 47 to 50, whose diameter was equal to 7.2 cm, a peripheral speed of approximately. 13.6m / s.
- the peripheral speed of the rotor element is equal to D representing the diameter of the rotor element in m and N the speed of rotation of the shaft 26 carrying the rotor, expressed in revolutions / second.
- D representing the diameter of the rotor element in m
- N the speed of rotation of the shaft 26 carrying the rotor, expressed in revolutions / second.
- the colloid mill Into the colloid mill, 80 parts of the bituminous binder, prepared as indicated above and having a temperature of 160 ° C., were continuously introduced, via line 8, and simultaneously, via line 9, 20 parts of the aqueous phase obtained. as described above and having a temperature of 60 ° C., with an overall flow rate of 300 kg / hour. The colloid mill was kept under pressure to avoid boiling of the water in the medium subjected emulsification, the temperature of which was approximately 125 ° C.
- the aqueous emulsion from the colloid mill was subjected to a first cooling by passage through a tubular exchanger, then to decompression at atmospheric pressure, after which the decompressed emulsion was cooled to room temperature over a period of about six hours to avoid thermal shock.
- binder content determined according to standard NF T 66 017 and expressed as a percentage by weight
- pH. sand breaking index determined according to standard NF T 66 017 at 20 ° C and 5 ° C and expressed in g of sand per 100g of emulsion
- pseudo-viscosity STV at 25 ° C determined according to standard NF T 66 020 and expressed in s; and. mean diameter of the bituminous binder globules determined from a particle size distribution obtained by laser light scattering using a device sold under the name CILAS 715.
- the aqueous phase was brought, via line 9, with a temperature of 80 ° C and the bituminous binder was brought, through line 8, with a temperature of 160 ° C, which led at a temperature of approximately 140 ° C. for the medium subjected to the emulsification in the emulsification enclosure and to the production of an emulsion of low viscosity.
- Example 1 In a colloid mill having the same characteristics as that used in Example 1 for the preparation of emulsion B according to the invention, 69 parts of the bituminous binder prepared as indicated in 1 'were continuously introduced, via line 8 example 1 and simultaneously, via line 9, 31 parts of the phase aqueous obtained as described in said example 1, said binder and said aqueous phase having an overall flow rate of 300 kg / hour and being at temperatures leading to the obtaining of a temperature of 113 ° C. in the premix zone 11 and in the shear zones of the emulsification enclosure (colloid mill).
- the aqueous emulsion from the colloid mill was treated as described in Example 1 to cool it to room temperature.
- the method according to the invention makes it possible to produce an emulsion with a low content of bitumen / polymer binder (approximately 69% by weight of binder) whose viscosity is comparable to that of a high content emulsion ( about 80% by weight) with the same binder, by adjusting the temperature in the emulsification enclosure.
- bitumen / polymer binder approximately 69% by weight of binder
- a high content emulsion about 80% by weight
- Two cationic emulsions were prepared, namely a control emulsion F and an emulsion G according to the invention, at 80% by weight of a bituminous binder consisting of a bitumen having a penetration of 180/220.
- control emulsion F In 1000 parts of water brought to 60 ° C., 10 parts of a cationic emulsifier marketed under the name DINORAM S and consisting essentially of fatty diamines were dispersed, then 6.5 parts of HCl were added to the dispersion obtained. 20 ° Bé and stirred everything until a clear liquid was obtained.
- DINORAM S a cationic emulsifier marketed under the name DINORAM S and consisting essentially of fatty diamines
- a conventional colloid mill consisting of a concentric frustoconical stator and rotor having a large diameter equal to 50mm and an air gap having a thickness of 0.3mm
- 800 parts of bitumen of penetration equal to 180 were continuously introduced / 220 brought to a temperature of 169 ° C and 200 parts of the aqueous phase at 60 "C prepared as indicated above, with an overall flow rate of 150 kg / hour.
- the colloid mill was kept under pressure to avoid boiling the water of the medium subjected to the emulsification 1, the temperature was about
- the rotational speed of the rotor was fixed at 6000 revolutions / minute, which corresponds to a peripheral speed of the rotor of approximately 15.7 m / s.
- emulsions with variable contents were prepared in a bituminous binder consisting of a bitumen having a penetration of 180/220, namely emulsions controls H and L and emulsions according to the invention I, J, and M.
- the aqueous phase used to produce these emulsions was obtained as described in Example 4.
- the control emulsion H was formed at atmospheric pressure by introducing into the colloid mill 600 parts of the bitumen brought to 156 "C and 400 parts of the aqueous phase, with an overall flow rate of 150 kg / hour. The emulsion from the colloid mill was then cooled to ambient temperature over a period of approximately six hours to avoid any thermal shock.
- the control emulsion L was produced by introducing into the colloid mill 700 parts of the bitumen brought to 160 ° C. and 300 parts of the aqueous phase, with an overall flow of
- the mill 1 of emulsification was held under pressure to prevent boiling of medium in the water subjected to the emulsification, said medium being at a temperature of
- Example 1 The emulsion from the colloid mill was treated as indicated in Example 1 to cool it to room temperature.
- the emulsion I was formed at atmospheric pressure by introducing into the colloid mill 600 parts of the bitumen brought to 105 ° C., via line 8, and 400 parts of the aqueous phase, through line 9, with an overall flow rate of 300 kg. /hour. The emulsion from the colloid mill was then cooled to room temperature over a period of about six hours to avoid any thermal shock.
- the emulsions J and K were produced by introducing into the colloid mill, through line 8, 650 parts of the bitumen and, through line 9, 350 parts of the aqueous phase, with an overall flow rate of 300 kg / hour and temperatures such that the medium subjected to the emulsification had a temperature of 130 "C for emulsion J and 105" C for emulsion K.
- the colloid mill was kept under pressure to avoid boiling of the water in the medium subject to emulsification.
- the emulsions from the colloid mill were treated as indicated in Example 1 to cool them to room temperature.
- the emulsion M was produced by introducing into the colloid mill, through line 8, 700 parts of the bitumen brought to 130 "C and, through line 9, 300 parts of the aqueous phase, with an overall flow rate of 300 kg / hour and a temperature of the aqueous phase such that the medium subjected to the emulsification was at a temperature of 110 ° C.
- the colloid mill was kept under pressure to avoid boiling of the water from the medium subjected to emulsification.
- the emulsion from the colloid mill was treated as indicated in Example 1 to cool it to room temperature.
- the emulsions I and M according to the invention have higher viscosities respectively than control H and L emulsions with comparable bitumen contents.
- a cationic emulsion P was prepared at 70% by weight of a bituminous binder of the polymer bitumen type consisting of the reaction product of a bitumen with a penetration equal to 67 with a block copolymer of styrene and butadiene, containing 25% by weight of styrene and having a viscous average molecular mass equal to approximately 75,000, in the presence of a coupling agent consisting of elemental sulfur.
- bituminous binder Preparation of bituminous binder:
- bituminous bitumen / polymer binder 964 parts of the bitumen were mixed with 35 parts of the block copolymer. After 3 hours of mixing with stirring, a homogeneous mass was obtained. To this mass maintained at 170 ° C., 1 part of crystallized sulfur was then added, then the whole was stirred for 60 minutes to form a bituminous bitumen / polymer binder.
- the bituminous binder thus produced had the following characteristics:. Viscosity (Pa.s): 8.5
- the colloid mill 700 parts of the bituminous binder prepared as indicated above and brought to 156 ° C. were introduced continuously via line 8, and 300 parts of the aqueous phase defined above, simultaneously through line 9, with an overall flow rate of 300 kg / hour, the medium subjected to the emulsification being at a temperature of 122 "C.
- the colloid mill was kept under pressure to prevent boiling of the water from the medium subjected to the emulsification.
- the emulsion from the colloid mill was treated as indicated in Example 1 to cool it to room temperature.
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- Chemical Kinetics & Catalysis (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Road Paving Structures (AREA)
- Adhesives Or Adhesive Processes (AREA)
- Emulsifying, Dispersing, Foam-Producing Or Wetting Agents (AREA)
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Abstract
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
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FR9115956A FR2685219B1 (fr) | 1991-12-23 | 1991-12-23 | Procede de production d'une emulsion d'un liant bitumineux permettant le controle de la viscosite et des qualites de rupture de l'emulsion. |
FR9115956 | 1991-12-23 | ||
PCT/FR1992/001211 WO1993012873A1 (fr) | 1991-12-23 | 1992-12-21 | Procede de production d'une emulsion d'un liant bitumineux permettant le controle de la viscosite et des qualites de rupture de l'emulsion |
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Publication Number | Publication Date |
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EP0572648A1 true EP0572648A1 (fr) | 1993-12-08 |
EP0572648B1 EP0572648B1 (fr) | 1996-03-20 |
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Application Number | Title | Priority Date | Filing Date |
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EP93902354A Expired - Lifetime EP0572648B1 (fr) | 1991-12-23 | 1992-12-21 | Procede de production d'une emulsion d'un liant bitumineux permettant le controle de la viscosite et des qualites de rupture de l'emulsion |
Country Status (10)
Country | Link |
---|---|
US (1) | US5374672A (fr) |
EP (1) | EP0572648B1 (fr) |
AT (1) | ATE135608T1 (fr) |
CA (1) | CA2104453A1 (fr) |
DE (1) | DE69209280D1 (fr) |
ES (1) | ES2056026B1 (fr) |
FR (1) | FR2685219B1 (fr) |
IT (1) | IT1256215B (fr) |
PT (1) | PT101155A (fr) |
WO (1) | WO1993012873A1 (fr) |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6001162A (en) * | 1997-07-17 | 1999-12-14 | Marathon Ashland Petroleum Llc | Sulfur-treated asphalt compositions and their preparation |
US6127461A (en) | 1998-04-21 | 2000-10-03 | Basf Corporation | Co-Agglomeration of random vinyl substituted aromatic/conjugated diolefin polymer with sulfur to improve homogeneity of polymer/asphalt admixtures |
US6133351A (en) * | 1999-06-03 | 2000-10-17 | Marathon Ashland Petroleum Llc | Sulfur-in-oil in asphalt and polymer composition and process |
US6468942B1 (en) | 2000-11-16 | 2002-10-22 | John J. Sansalone | Absorptive-filtration media for the capture of waterborne or airborne constituents |
US7341661B2 (en) * | 2000-11-16 | 2008-03-11 | Unit Process Technologies, L.L.C. | Clarification and sorptive-filtration system for the capture of constituents and particulate matter in liquids and gases |
US7449131B2 (en) * | 2004-10-06 | 2008-11-11 | Terry Industries, Inc. | Techniques and compositions for shielding radioactive energy |
US20100222468A1 (en) * | 2009-02-27 | 2010-09-02 | Semmaterials, L.P. | Crack resistant layer with good beam fatigue properties and method of selecting same |
US20100222466A1 (en) * | 2009-02-27 | 2010-09-02 | Semmaterials, L.P. | Crack resistant layer with good beam fatigue properties made from an emulsion of a polymer modified bituminous binder and method of selecting same |
US20100222465A1 (en) * | 2009-02-27 | 2010-09-02 | Semmaterials, L.P. | Crack resistant layer with good mixture fracture energy and method of selecting same |
US20100222469A1 (en) * | 2009-02-27 | 2010-09-02 | Semmaterials, L.P. | A crack resistant layer with good binder fracture energy properties and method of selecting same |
US20100222464A1 (en) * | 2009-02-27 | 2010-09-02 | Semmaterials, L.P. | Emulsion of a polymer modified asphalt |
US20100222467A1 (en) * | 2009-02-27 | 2010-09-02 | Semmaterials, L.P. | crack resistent layer with good mixture fracture energy made from an emulsion of a polymer modified bituminous binder and method of selecting same |
GB201515000D0 (en) * | 2015-08-24 | 2015-10-07 | Univ Nottingham Trent | Reactor |
CN106273023A (zh) * | 2016-10-17 | 2017-01-04 | 郑州峰泰纳米材料有限公司 | 一种动态混合器 |
CN106493894A (zh) * | 2016-10-17 | 2017-03-15 | 郑州峰泰纳米材料有限公司 | 一种在线动态混合器 |
US11732108B1 (en) | 2019-07-03 | 2023-08-22 | Associated Asphalt Partners, Llc | Modified asphalt compositions containing dialkyl polysulfides |
CN113416426B (zh) * | 2021-07-01 | 2022-09-23 | 海南恒建沥青路面有限公司 | 一种sbs复合改性沥青的制备方法 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3127367A (en) * | 1964-03-31 | Method and apparatus for adding latex to hot bitumen | ||
DE1103301B (de) * | 1959-08-10 | 1961-03-30 | Ernst A Reiffen Dipl Ing | Kontinuierlich arbeitendes Dispergiergeraet |
SE362382B (fr) * | 1972-03-28 | 1973-12-10 | K G Ohlson | |
US4314921A (en) * | 1980-01-14 | 1982-02-09 | Novophalt Sa | Method and apparatus for preparing a bituminous binder |
US4722953A (en) * | 1983-12-16 | 1988-02-02 | Davlin Paint Company | Method of producing bituminous/polymer emulsion and product |
JP2925599B2 (ja) * | 1989-11-02 | 1999-07-28 | 住友重機械工業株式会社 | 高粘度液処理装置 |
-
1991
- 1991-12-23 FR FR9115956A patent/FR2685219B1/fr not_active Expired - Fee Related
-
1992
- 1992-12-21 DE DE69209280T patent/DE69209280D1/de not_active Expired - Lifetime
- 1992-12-21 WO PCT/FR1992/001211 patent/WO1993012873A1/fr active IP Right Grant
- 1992-12-21 CA CA002104453A patent/CA2104453A1/fr not_active Abandoned
- 1992-12-21 AT AT93902354T patent/ATE135608T1/de not_active IP Right Cessation
- 1992-12-21 US US08/108,559 patent/US5374672A/en not_active Expired - Fee Related
- 1992-12-21 EP EP93902354A patent/EP0572648B1/fr not_active Expired - Lifetime
- 1992-12-22 PT PT101155A patent/PT101155A/pt not_active Application Discontinuation
- 1992-12-22 IT ITMI922925A patent/IT1256215B/it active IP Right Grant
- 1992-12-23 ES ES09202599A patent/ES2056026B1/es not_active Expired - Fee Related
Non-Patent Citations (1)
Title |
---|
See references of WO9312873A1 * |
Also Published As
Publication number | Publication date |
---|---|
ITMI922925A1 (it) | 1994-06-22 |
FR2685219B1 (fr) | 1994-04-15 |
WO1993012873A1 (fr) | 1993-07-08 |
CA2104453A1 (fr) | 1993-06-24 |
FR2685219A1 (fr) | 1993-06-25 |
EP0572648B1 (fr) | 1996-03-20 |
PT101155A (pt) | 1994-07-29 |
US5374672A (en) | 1994-12-20 |
IT1256215B (it) | 1995-11-29 |
ATE135608T1 (de) | 1996-04-15 |
ITMI922925A0 (it) | 1992-12-22 |
DE69209280D1 (de) | 1996-04-25 |
ES2056026B1 (es) | 1995-05-01 |
ES2056026A1 (es) | 1994-09-16 |
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