Glass melting furnace

Abstract

Glass is made from a feed consisting of batch materials and cullet in a furnace that is both electrically and gas fired. A batch-only hopper discharges through a blanket conveyor to a batch melting chamber that is electrically fired and is connected via a submerged throat to a fritting chamber where the at least partly molten batch materials are mixed with cullet fed from cullet-only hoppers by blanket feeders. The fritting chamber is fired by a combination of electricity and roof-mounted flat flame burners. Material passes from the fritting chamber to a secondary reheating and refining chamber which is heated by regenerative gas burners. The separation of batch materials from cullet and separate melting thereof in a pre-melter means that the feed to the secondary refining and conditioning chamber is relatively free of fines and requirement to melt only cullet in the fritting chamber and secondary refining chamber enables those chambers to be operated at a lower temperature than the batch melting chamber. The resulting furnace makes efficient use of gaseous combustion and electrical energy and has low emissions of fines and oxides of nitrogen.