PL101436B1 - METHOD OF MAKING MODIFIED ROAD ASPHALT - Google Patents

Description

The subject of the invention is a method for producing road asphalts modified with products thermal destruction of rubber, intended especially for the construction of asphalt road surfaces.

There are known methods of modifying road asphalts by introducing rubbers into the asphalt, resins, polymers that are difficult to mix directly with asphalt, in the form of a water emulsion or a solution in low-boiling solvents. After distilling off water or solvent, a homogeneous i is obtained stable modified asphalt. There is also a known method of introducing rubber into asphalts consisting in heating the mixture of crushed gum and aromatic solvent boiling within 100 to 220 ° C in the presence of a gum decomposition catalyst and at a temperature of 120 to 180 ° C. The resulting solution The processed rubber is mixed with the asphalt and then the solvent is distilled off. In the patent description of the Polish People's Republic No. 97435 describes a method for the preparation of a homogeneous mixture of asphalt and thermal destruction products rubber.

The essence of the invention. The essence of the invention is to prepare a mixture of asphalt and thermal products destruction of rubber waste with favorable properties for use in the construction of asphalt road surfaces. The process consists in distilling light asphalt from a solution of reclaimed rubber oil formed by the decomposition of rubber and some of the oil contained in the asphalt. Used as rubber waste worn out tires, tubes, conveyor belts, industrial rubber waste, etc.

In addition to rubber, rubber waste may contain cord and other ingredients. <* ' In the method according to the invention, the modifying component is obtained by heating and mixing the waste rubber at a temperature of 240 to 380 ° C in the environment of petroleum asphalt, or extracts after refining selective mineral oils or heavy products of destructive processing of petroleum products, or heavy products coal tar in an amount of 1 to 80% by weight per charge. The resulting mixture homogeneous is introduced into petroleum or natural asphalt in such an amount as to be processed waste rubber in the finished asphalt was 1 to 50% by weight.

The modifier is otherwise produced directly in the asphalt by incorporating 1 to 50% by weight of rubber waste, based on the input to distillation or oxidized asphalt, or after refining2 101436 propane, or natural gas and heating and stirring at 240 to 380 ° C until obtained homogeneous mixture.

The paraffin content of bitumens and asphalt intermediates should be less than 6% by weight. A homogeneous mixture of products of thermal destruction produced in this way rubber, asphalt, semi-finished products for the production of road asphalts are distilled under low pressure or steam distillation, preferably distilling oils boiling below the temperature 550 ° C to obtain a product with a flash point according to the Marcuson method preferably above 200 ° C.

In the process of distillation, low-boiling products of thermal destruction of rubber and are separated from the mixture partially low molecular weight oils contained in bitumen or incorporated into the rubber dissolution process.

Low-boiling products of thermal destruction of rubber have a high content of unsaturated hydrocarbons and They are characterized by chemical instability and an unpleasant odor. Their distillation improves stability asphalt thermo-oxidative, increases the ignition temperature, increases the drop point and lowers the penetration qe of asphalt, increases the resistance of asphalt to weathering and adhesion to aggregates mineral. Distilling light rubber breakdown products facilitate distillation of light oils from asphalt by reducing their vapor pressure and viscosity, which is a phenomenon that positively affects the quality of asphalt.

This enriches the asphalt with resins and asphaltenes and oils with high molecular weight, and lowers the content of coarse-crystalline paraffins.

The method according to the invention makes it possible to obtain solutions of reclaimed rubber in asphalts and intermediates used in the manufacture of asphalts at lower temperatures and shorter mixing times thanks to the possibility of using solvents containing more oil and therefore less viscosity and greater dissolving power. Modified road bitumens obtained in the manner described may be used for the construction of an asphalt surface directly or after additional composition with asphalt road and unmodified. A mixture of asphalt and products of thermal rubber destruction, can be subjected to additional processing and modification such as petroleum asphalts, for example compressed air oxidation.

Example I. 77 kg of distillation asphalt with a softening point, the Ring and Ball method 23 i paraffin content 3.6% by weight was mixed with 23 kg of crushed car tires along with the cord after stripping the wire and heated at 330 ° C for 3 hours.

The resulting homogeneous solution was purged with steam overheated to 380 ° C for 1 hour then heated to a temperature of 340 ° C and under a pressure of 10 Torr 12% by weight of oils were distilled off low-boiling.

Road asphalt was obtained with the properties: softening point, Ring and Ball method, ° C 47 penetration at 25 ° C 74 flash point, ° C 236 frash point temperature, ° C —7 paraffin content,% 2.9 volatility,% 0.7 penetration after evaporation at 165 ° C,% 51 Example II. 70 kg of used tire granules, and 30 kg of pofurfurol extract with a viscosity of 1.7 ° E in 100 ° C is heated and stirred at 280 ° C for 8 hours. 20 kg of the resulting solution Reclaimed rubber and 80 kg of oxidized road asphalt, penetration at 25 ° C 39 and paraffin content of 2.1% are mixed and then, at a temperature of 315 ° C, steam is blown through, which has been superheated to temperature 400 ° C for 2 hours.

Receives asphalt in the ownership of: penetration at 25 ° C 34 softening temperature, ° C 56 flash point, ° C 226 ductility at 25 ° C 71 brittle temperature, ° C -8 Example III. 30 kg of distillation asphalt with a melting point of 41 and 30 kg of anthracene oil A mixture with a boiling point of 280 to 330 ° C was mixed and heated at 250 ° C with 40 kg of waste industrial rubber containing 38% by weight of vulcanized styrene-butadiene rubber and 22% by weight of unvulcanized rubber for 8 hours. The resulting homogeneous mixture was mixed in a 1 to 2 ratio with still asphalt and distilled under a pressure of 34 torr with additive superheated steam. 38 kg of oil distillate and 62 kg of modified asphalt were obtained, with properties: 101 436 3 penetration at 25 ° C 93 softening temperature, ° C 48 flash point, ° C 221 toughness at 25 ° C, cm above 100 toughness at 25 ° C, cm above 100 paraffin content,% 1.8

Claims (2)

Patent claims 1. The method of obtaining modified road bitumens, characterized in that the bitumen or semi-products used for the preparation of bitumens with a paraffin content below 6% by weight, is mixed with the products of thermal destruction of rubber waste in such an amount that the content of processed rubber waste in the finished modified bitumen is 1 50% by weight, with the product of thermal destruction of rubber waste obtained by heating rubber waste at a temperature of 240 to 380 ° C in the environment of petroleum bitumens or extracts after selective refining of mineral oils or heavy products from destructive processing of petroleum products or heavy distillation products coal tar and the obtained homogeneous mixture of the product of destruction of rubber waste and hydrocarbons is distilled under reduced pressure or with steam and gives off low-molecular oils, not used in road bitumens. 2. The method according to claim The method of claim 1, characterized in that the destruction of the rubber waste is carried out while the low-boiling components are distilled off.