AFS Mid kiln valves are designed to introduce Whole Tires or Bulk Fuel ~ midway along the length of a rotating kiln. At this point, temperatures are high enough and residence times long enough to ensure complete combustion of the fuel. Fuel injection occurs once every kiln rotation.
AFS standard Mid-Kiln Valves have the following features to provide years of reliable service with little maintenance:
- A fuel staging chute above the kiln for release of fuel into a mid-kiln valve. A chute capacity of ~ 40 cubic feet (eight tires).
- An actuator cam, typically mounted above the kiln, to open the Mid kiln valve at the proper position.
- A fuel chute on the Mid-kiln valve
- A Pivot-type bottom gate on the Mid-kiln valve made of a high temperature alloy supported with two high temperature graphite pillow block bearings
- Fuel injection tube inside the kiln made of a high temperature alloy rated for 1100° C in high sulfur gas conditions.