Protective atmosphere heating

摘要

A method for heating and/or melting a charge (3) such as aluminum in a furnace (1) using heat generated by combustion to radiatively heat the charge through a layer of protective gas (12) wherein combustion reaction products generated by the combustion are exhausted from a lower level within the furnace, and, during melting, the protective gas layer (12) has a higher upper boundary (10) than during a subsequent heating period, enabling reduced NOx generation, lower fuel and oxygen consumption and reduced refractory corrosion by avoiding furnace gas flow through the high temperature upper furnace region.