Heat processing of particulate material and apparatus therefor.

摘要

Apparatus for heat processing of particulate material, in particular crushed glass to form glass beads, comprises a generally cyclindrical furnace (1) having a canopy (27) providing an exhaust gas outlet (60). A gas/air mixture is fed to the furnace (1) through a central burner and is ignited to form a flame in which the combustion gases have a speed of less than 10 m/s. A current of air is introduced by fans (18) through inlets (16) into the furnace (1) and forms a quenching zone in which the current of air swirls around the flame. Particles of crushed glass are fed by a screw feeder (39) into a chamber (41) in which they are entrained in a current of air from a compressor (43) and thereby introduced into the furnace (1) through nozzles arranged around the burner. A further gas/air mixture is introduced into the furnace (1) at a position spaced radially outwards from the central burner. The particles of crushed glass follow a trajectory through the hot central portion of the flame, where they form beads, into the quenching zone and are either collected through outlet ports (22) in the floor of the furnace (1) or from the exhaust gases by means of a cyclone.