The APCOS™ technology is a tuyere-based system that operates in conjunction with a cupola's current blast air. The technology uses a proprietary burner design that injects supersonic oxygen and natural gas to replace coke, allow coke substitutions and/or increase production. The APCOS burner can also accommodate solids injection through the burner, with the heat of the oxy-fuel flame allowing solids injection without cooling the melt zone. The rapid response of heat and solids injection at the tuyeres allows operators to control the cupola and recover from upsets. The APCOS burners can be controlled individually or as a group, and burners can be placed in a single tuyere, alternate tuyeres or all tuyeres. The burner is designed to allow optimal heat release and supersonic injection across a wide range of heat inputs. The flow controls for the burner system and safety interlocks can be integrated into the cupola control system and feature data acquisition and reporting capabilities.