Abstract: An air supply apparatus includes a plurality of movable carriages arranged along a circular carriage path; a movable circular duct arranged along the carriage path and connected to each of the carriages through a connection air duct; a water sealing device including a circular water seal chamber arranged along the carriage path and a water sealing plate having a lower end part thereof sunk in sealing water in the circular water seal chamber; a stationary circular duct arranged along the carriage path and fitted into the movable circular duct through the water sealing device to be freely movable, wherein the movable circular duct and the stationary circular duct form a circular air path; and an atmospheric zone that stops leakage of air in the carriage being provided in a predetermined position of the carriage path, wherein an upper space of the circular water seal chamber on a circular air path side communicates with the circular air path on a movable circular duct side, the circular air path on the movable c

Abstract: The invention relates to a cooling apparatus for hot bulk material, such as sintered ore. Gaps are defined between respective lower ends of side wall portions of a moveable annular air duct and respective upper ends of side wall portions of a stationary annular air duct, which gaps communicate the air passage in the stationary annular air duct with annular water seal chambers. First seal plates are disposed at respective upper ends of the side wall portions of the stationary annular air duct in relation to respective lower ends of the side wall portions of the moveable annular air duct. Second seal plates are disposed at respective lower ends of the side wall portions of the movable annular air duct. Labyrinth seals are formed by the first seal plates, the side wall portions of the moveable annular air duct, and the second seal plates in combination. This seal arrangement is entirely different from the conventional seal structure which involves sliding contact of seal members with other surfaces.