Patent ID: 7044630

Claim:
A method for continuously drying and heating aggregate for an asphalt plant, the steps of said method comprising: orienting in a substantially horizontal attitude a rotatable cylinder having first and second ends with an internal passageway communicating therebetween and having first and second zones, with each said zone having first and second ends; rotating said cylinder; delivering primary aggregate material to the first end of said cylinder whereby rotation of said cylinder transports said aggregate material from said first end of said cylinder, through said first and second zones, to said second end of said cylinder; generating a hot gas stream in said second zone of said cylinder to flow toward said first end of said cylinder in a countercurrent direction to the flow of aggregate material within said cylinder in order to heat and dry the aggregate material within said first zone; introducing secondary material directly within said second zone of said cylinder whereby rotation of said cylinder transports said secondary material through said second zone to said second end of said cylinder; discharging said primary and secondary materials from said second end of said cylinder; and heating said hot gas stream discharged from the first end of said cylinder to elevate the temperature of said discharged hot gas stream prior to delivery to air pollution control equipment.