METHOD AND DEVICE FOR PRODUCTION OF EXPANDED GRANULATE Russian patent published in 2019 - IPC C04B20/06 F27B1/00 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to a method and device for producing expanded perlite or obsidian sand granules. Method for production of expanded granulate (29) made from sand mineral material (1) in form of grains, using a propellant, in particular, production of expanded pearlite sand (1) or obsidian sand; in which material (1) is fed into mainly vertical furnace (2), in which material (1) is transported in direction of transportation (4) through plurality of vertically separated heating zones (5) in furnace (3) of furnace (2), in wherein each heating zone (5) is configured to be heated by at least one independently controlled heating element (6); wherein material (1) is heated to critical temperature, at which surfaces of grains of sand (1) become plastic, and grains of sand (1) are swollen using a propellant; and expanded granulate (29) is unloaded from furnace (2), includes a stage, at which material (1) is supplied together with air volume from below, wherein material (1) is transported from below upwards in direction of transportation (4) by means of air volume, which flows from bottom to top inside furnace shaft (3) and forms air flow (14), and swelling of grains of sand (1) takes place in upper half, preferably in uppermost one-third of transportation (4). Group of inventions is developed in dependent claims.

EFFECT: technical result is creation of improved method of bulging and device, which allow to bulge fine-grained material.

22 cl, 2 dwg