Continuous metal melting process

Abstract

A continuous process is provided for rapid melting of a variety of virgin and recycled ferrous and non-ferrous metals. This is accomplished by distributing the introduction of the unmelted charge materials and hence the melting heat requirements along an elongate gas-solid-liquid reaction zone within a rotary furnace, according to the distribution of heat available to effect melting. In the case of fine-sized metal charge materials, fluxes and additive reagents, this charge distribution is implemented by traversing of the nozzle jet, as directed to penetrate into the metal and slag bath from a solids injection lance, successively backwards and forwards and, in the case of coarse-sized materials, by traversing of the discharge from an oscillating conveyor. A preferred embodiment includes longitudinal extension of the furnace to include a gas-liquid reaction zone adapted for conducting refining reactions and adjusting metal temperature prior to discharging, as heated by a burner generating hot furnace gases which flow countercurrent to the general metal movement. The discharge of liquid metal and slag can be via tap hole, vacuum siphon or overflowing the annular lip of the discharge opening. The direct introduction of heat and selective introduction of oxygen along the gas-solid-liquid reaction zone is also preferred for effecting substantially complete combustion of furnace gases to CO2 and H2O before exhausting from the furnace. Recirculation of a major portion of the exhaust gases into the gas-liquid reaction zone is an optional feature.

Dependencies are inferred from the claim text.