Abstract: A grate plate for use in cooling heated material has a plurality of spaced apart walls including a front wall, side walls, a top wall and a bottom wall. A plenum is located generally within the walls for receiving a cooling fluid within the grate plate. The top wall has a trough for receiving heated material. An opening in the grate plate is located rearwardly of the front wall for receiving the cooling fluid into the plenum. The plenum is shaped for delivering air from the opening to the front wall of the grate plate and then rearwardly adjacent to a side wall of the trough. A port in the trough permits exhaust of the cooling fluid from the exhaust duct into the trough for cooling the heated material on the grate plate.