Apparatus and method for maximizing rap content in paving

A method for preparing renewed amalgam asphalt from recycled asphalt product (RAP), in steps, which need not be in precise order in all cases, comprising

• A. Positioning the core components of the asphalt production apparatus (APA), comprising an ignition cylinder, a mixing drum, and a capture trap, in an aligned inclined orientation about a longitudinal central axis from an upper intake end to a lower outflow end where said mixing drum mates with said capture trap;
• B. Initiating rotation of said mixing drum to a predetermined rotation rate and igniting combustion fuel in said ignition cylinder to preheat said mixing drum by propelling flaming gas through a series of radially arrayed combustion tubes on the interior surface of said mixing drum until a predetermined optimal temperature is achieved;
• C. Delivering crushed recycled asphalt product (RAP) into said rotating mixing drum by activating a RAP hopper having a dispensing funnel aligned with radially aligned RAP input ports on said mixing drum, such that said RAP conductively abuts against successive combustion tubes as said mixing drum rotates and the RAP is gradually propelled by gravity toward said capture trap, with additional heating being provides by post-combustion spent gases returned though said mixing drum from said capture trap, with a minimal injection of oil in the lower portion of the passage of the RAP downward through said mixing drum to convert the heated RAP into the desired renewed amalgam by the end of the passage;
• and
• D. Collecting the heated renewed amalgam in said capture trap, such that the rotation of said mixing drum causes tube extensions extending from said combustion tubes into said capture trap to carry said amalgam to a return chute for delivery to transport units for use in paving, while at least some of said spent gases are deflected upward by a back wall of said capture trap and forced back through said mixing drum for a second pass through said mixing drum and to exit via a plurality of exhaust ports.

An asphalt production apparatus (APA) adapted to utilize a significant material percentage of recycled asphalt product (RAP) while avoiding flaming gas contact with input materials, comprising:

• input means for delivering raw materials, including RAP, combustible fuel, and air;
• an ignition chamber for igniting said fuel into flaming gas;
• an inclined rotating mixing drum having a central shell segment for receiving RAP and raw materials, said mixing drum having a plurality of radially spaced hollow combustion tubes for mating with said combustion chamber, said combustion tubes extending longitudinally about the interior of said shell segment, with said combustion tubes being isolated from the interior of said shell segment for the length thereof;
• and
• a capture trap extending beyond the lower end of said mixing drum to receive and dispense renewed amalgam from said mixing drum;
• wherein
• said flaming gas is driven into and through said combustion tubes to heat said combustion tubes for delivering thermal energy conductively to said RAP at a rate that flaming gas is consumed therewithin and only spent gases reach said capture trap.