Patent ID: 7906011

Claim:
A method for manufacturing a modified asphalt, comprising: flowing a base asphalt at a base asphalt flow rate through an in-line rotor-stator mixer having a maximum power rating, the in-line rotor-stator mixer having openings therein configured to allow an oxygen-containing gas to be blown through the base asphalt while flowing the base asphalt through the in-line rotor-stator mixer; and agitating the base asphalt at a high shear rate using the rotor-stator mixer while simultaneously (a) blowing the oxygen-containing gas at a high gas flow rate through the openings in the rotor-stator mixer and (b) heating the base asphalt at an elevated temperature for a treatment time to thereby produce a modified asphalt; wherein the base asphalt flow rate, the high gas flow rate, the high shear rate, the elevated temperature and the treatment time are all selected to substantially improve both the rutting resistance and the fatigue resistance of the modified asphalt as compared to the base asphalt.