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US 4,692,350 AGranted
Asphalt coating method
AssigneeMobil Oil Corporation
InventorsAubrey R. Clarke, Colin L. Martin, Robert H. Bowering
Life of this patent
Estimating the term…
Abstract
Substrates such as aggregates, particularly for roadbuilding, are coated with asphalt by foaming the asphalt and mixing the hot asphalt foam with the aggregate. The asphalt is foamed by dispersing water in the hot asphalt as to maintain the water in the liquid phase and then vaporizing the water to form the foam structure.
Claims24
A method of forming a coating of an asphaltic base material on a substrate which comprises:
- (a) combining a heated, liquid asphaltic base material with a liquid foaming agent in an adiabatic dispersion zone to form a dispersion of the foaming agent and base material, wherein the heat content of the dispersion so formed is sufficient to cause vaporization of the foaming agent at atmospheric pressure,
- (b) discharging the dispersion from the adiabatic dispersion zone to atmospheric pressure thereby forming a foam of the base material and
- (c) applying the foam so formed to the substrate without substantial heating of the substrate.
A method of forming a coating of an asphaltic base material on a substrate which comprises:
- (a) combining without mechanical mixing a heated liquid asphaltic base material with a liquid foaming agent in weight ratio of about 1:33 to 1:150 of the foaming agent to the base material in an adiabatic dispersion zone to form a dispersion of the foaming agent and base material, wherein the heat content of the dispersion so formed is sufficient to cause vaporization of the foaming agent at atmospheric pressure,
- (b) discharging the dispersion from the adiabatic dispersion zone to atmospheric pressure thereby forming a foam of the base material and
- (c) applying the foam so formed to the substrate.
A method of coating a substrate with asphalt comprising
- continuously passing a stream of hot asphalt through a dispersion zone to a second zone at ambient conditions
- wherein the temperature of said hot asphalt is sufficient to vaporize water at the ambient conditions of said second zone;
- foaming said hot asphalt by the step consisting of directing a continuous stream of water in the liquid state into said stream of hot asphalt in said dispersion zone, to thereby form a dispersion of liquid in water in said asphalt in said dispersion zone wherein the inherent result of said continuously passing said hot asphalt to said dispersion zone and said step for foaming in that said dispersion is formed under substantially adiabatic conditions;
- wherein the weight ratios of liquid to water in said dispersion ranges from 1:5 to 1:150;
- whereby the stream of hot asphalt foams in said second zone;
- and, after foaming directly applying the foamed asphalt to a substrate in said second zone.
3 more elements
A method of coating a substrate with asphalt comprising:
- continuously passing a stream of hot asphalt through a dispersion zone to a second zone at ambient conditions,
- wherein the temperature of said hot asphalt is sufficient to vaporize water at the ambient conditions of said second zone;
- foaming said hot asphalt by the step consisting of directing a continuous stream of water in the liquid state into said stream of hot asphalt in said dispersion zone, to thereby form a dispersion of liquid in water in said asphalt in said dispersion zone;
- wherein the weight ratios of liquid to water in said dispersion ranges from 1:5 to 1:150;
- whereby the stream of hot asphalt foams in said second zone;
- and, after foaming,
- directly applying the foamed asphalt to a substrate in said second zone,
- wherein the inherent result of said continuously passing said hot asphalt to said dispersion zone and said step for foaming is that said dispersion is formed under substantially adiabatic conditions.
5 more elements
Dependencies are inferred from the claim text.