Feed Shelf Firing

For Preheater & Precalciner Kilns, AFS Technology provides automated fuel feed systems that introduce Whole Tires and other Bulk Fuels to the feed shelf for staged combustion.  The fuel is gravity-fed in an environment designed to maintain negative pressure and minimize the introduction of outside air for optimal NOx reduction potential.

KILN TYPES: 4-Stage Preheaters; Precalciners

FUEL SPECIFICATIONS: Whole scrap tires up to 48″ in diameter.

FUEL FEED RATE: Standard ten-second gate-release interval designed up to feed 6 tires per minute, adjustable through PLC and/or Control Room Interface.


  • 4-Stage Preheaters:  20% whole tires; 30% with Mixing Air
  • Precalciners:  5% whole tires fired on feed shelf; up to 30% when supplemented or replaced with Suspension Burning in calciner or riser duct.

NOx REDUCTION POTENTIAL: Up to 40% using whole tires; may exceed 50% using whole tires + Mixing Air

SYSTEM COMPONENTS (Full Automation): Double-Gate Airlock Valve | Weigh Feed Conveyor | Electrical Controls | Zoned Accumulation Conveyor(s) | Vertical Conveyor | Ground Systems Automation