 Image Number 19 for United States Patent #5322367.
A process for the production of hot mix asphalt (HMA) by the treatment of virgin material alone or adding reclaimed or recycled asphalt pavement (RAP) (up to 100% of the HMA). 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 process is controlled by a micro-processor which controls RAP temperature, mixture gradation, emissions and production rate as a function of measured drum conditions such as temperature at the drum inlet, drum speed, drum slope, drum RPM, output hydrocarbons, drum gas outlet temperature, and amount of aggregate added.
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