Abstract

A method for forming small, smooth surfaced foamed glass pellets with a coated surface of ash is disclosed. The method involves the recovery of waste glass, typically soda/lime/silica glass, crushing and sizing same to obtain particles of less than 200 mesh. The small particles may be pelletized in a pelletizing disk, drum, rotary kiln or other compressive or extrusion devices by the addition of water until the small particles begin to agglomerate. The pellets are then coated with a high-melting point release agent, especially ash, and then heated to a temperature above the softening point of the glass to cellulate the glass agglomerates to form substantially spherical pellets having a bulk density of as low as eight pounds per cubic foot and possessing a very fine, substantially uniform pore structure. The pellets have numerous uses as bulk insulating material and as lightweight aggregate for addition to various matrices, including various resinous thermoplastic and thermosetting materials, and to inorganic bodies such as gypsum, plaster and particularly concrete.