A method for modifying asphalt comprises blowing an oxygen-containing gas through a base asphalt at a high gas flow rate while simultaneously agitating the base asphalt at a high shear rate and at an elevated temperature for a period of time that is effective to substantially improve at least two paving properties of the base asphalt. In preferred embodiments, modified asphalts are produced having both substantially improved rutting resistance and substantially improved fatigue resistance as compared to the base asphalt.
Methods and systems for efficiently manufacturing modified asphalt materials include agitating a base asphalt at a high shear rate using an in-line mixer while simultaneously exposing the asphalt to oxygen by blowing an oxygen-containing gas at a high gas flow rate through openings in the in-line mixer and heating the asphalt at an elevated temperature.
B28C 5/38 - Apparatus or methods for producing mixtures of cement with other substances, e.g. slurries, mortars, porous or fibrous compositions wherein the mixing is effected both by the action of a fluid and by directly-acting driven mechanical means, e.g. stirring means
A method for modifying asphalt comprises blowing an oxygen-containing gas through a base asphalt at a high gas flow rate while simultaneously agitating the base asphalt at a high shear rate and at an elevated temperature for a period of time that is effective to substantially improve at least two paving properties of the base asphalt. In preferred embodiments, modified asphalts are produced having both substantially improved rutting resistance and substantially improved fatigue resistance as compared to the base asphalt.
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