METHOD FOR PRODUCING GLASS MICROSPHERES Russian patent published in 1997 - IPC

FIELD: production of glass microspheres for use, as inorganic finely dispersed fillers, in plastics in chemical industry, for abrasive-blasting treatment of metal products in mechanical engineering, etc. SUBSTANCE: proposed method comprises step of preparing glass micropowders by combining process of comminuting granular glass feedstock and that of sizing glass powders. Latter are fed into microsphere shaping furnace by flow of pre-heated compressed air, pre-heated being achieved in spiral-type heat exchanger by gases leaving shaping furnace. Shaping of microspheres is carried out in gas-flame flow generated by burner assembly consisting of plurality of nozzles arranged in concentric array in relation to axis of microsphere shaping furnace. Gas-flame flow for shaping microspheres is generated inside flame tube consisting of plurality of conical tubular sections received one into another with circular clearance therebetween. Air supplied to support fuel combustion is pre-heated in space defined by outer shell of shaping furnace and flame tube, air being forcibly injected into upper portion of furnace. Glass microspheres thus shaped are cooled down by admitting sucked-in cold atmospheric air, whereupon microspheres are subjected to additional two-step sizing classification. EFFECT: cheap good-quality glass microspheres can be thus produced. 1 dwg