An apparatus and process is provided for the production of hot mix asphalt (HMA) by the treatment of virgin material alone or adding reclaimed or recycled asphalt pavement (RAP) of up to 100% of the HMA comprised of reclaimed asphaltic pavement (RAP). The HMA is first heated in either a parallel or a counter flow rotating drum which is supplied with hot combustion gases generated by a remote low NO.sub.x burner. The temperature of hot gases entering the drum is from about 400.degree. to 2,000.degree. F., and the temperature of gases exiting from the drum is from about 130.degree. to 220.degree. F. The HMA material optionally can be subjected to microwave radiation to raise the material to a final temperature, or optionally to only reorient the dipolar molecules of the material without any measurable heating of the material. The exhaust gas is treated and made environmentally safe. The hot gases exiting from the drum are passed through a knockout box and then through a baghouse having acrylic bags coated with a protective layer of particulate material. The gases exiting the baghouse are passed through an oxidizer to further remove smoke and asphaltic material and at least a portion of the gases from the oxidizer are recycled through a heat exchanger.