Apparatus for and methods of producing a hot asphaltic material

Apparatus for producing hot asphaltic material, the apparatus comprising:

• a frame;
• means mounted to the frame for supporting a drum drier including means for rotatably supporting a drum of such drier for rotation about an axis longitudinally parallel to the frame;
• a drum rotatably mounted to the support means on the frame, the drum including an aggregate feed port at a first end thereof for feeding an aggregate material into the drum, and an aggregate discharge end at a second end thereof for discharging the aggregate material from the drum;
• a burner assembly mounted to the frame, the burner assembly including a burner nozzle adapted to sustain a flame, a blower connected to the burner nozzle for supplying a primary source of air to the burner for sustaining combustion at the flame within the burner during the operation of the burner and for generating a forced plume of hot combustion gases, and a combustion chamber having a cylindrical wall structure disposed centered about the nozzle and forming at one end thereof an annular opening between itself and said nozzle, said annular opening capable of admitting secondary air directly to said flame, the other end of said cylindrical wall structure forming a circular opening toward and in communication with the drum at the discharge and of the drum;
• a pugmill mounted to the frame adjacent the discharge end of the drum, the pugmill having a first region including means for receiving aggregate material and for mixing said aggregate material, and a second region including means for injecting liquid asphaltic cement into said mixed aggregate material, for further mixing said aggregate material and said asphaltic cement and for discharging an asphaltic material comprised of said mixed aggregate and asphaltic cement from said apparatus, the discharge end of the drum being communicatively coupled to said first region of said pugmill for discharging aggregate material from the drum into said first region of the pugmill;
• and
• a secondary air supply chamber formed by the second region of the pugmill at the base of the chamber, a housing enclosing the pugmill, and an upper chamber including a partition dividing said first region of the pugmill from said second region, said secondary air supply chamber having access means for admitting secondary air from the environment, said secondary air supply chamber being communicatively coupled to said annular opening formed by the combustion chamber with said burner nozzle, whereby upon operation of the burner gases are drawn from said secondary air supply chamber including a space above the second region of the pugmill and into the flame.