Methods for preheating metal-containing pellets

A method for preheating metal pellets before charging into a melting furnace, wherein the pellets are transported by a conveyor belt to a chute and discharged from the chute into the melting furnace, the method comprising:

• heating the pellets by direct flame impingement from two or more banks of burners, wherein the two or more banks of burners comprise an upstream bank of burners and a downstream bank of burners;
• controlling the upstream bank of burners to operate oxygen-rich so as to create an oxidizing zone and the downstream bank of burners to operate fuel-rich so as to create a reducing zone;
• measuring at least one process condition;
• and
• controlling the two or more banks of burners based on the at least one process condition;
• wherein when the at least one process condition is a concentration of one or more gases in the hot flue gas, adjusting the two or more banks of burners based on the concentration of one or more gases in the hot flue gas;
• wherein when the at least one process condition is one or more temperatures selected from the list of the gas temperature, pellet temperature, or belt temperature, adjusting the two or more banks of burners based on the one or more temperatures;
• and
• wherein when the at least one process condition is a safety condition, shutting down the two or more banks of burners in the event the safety condition is detected.