Feasibility Study of Regenerative Burners in Aluminum Holding Furnaces

Gas-fired aluminum holding reverberatory furnaces are currently considered to be the lowest efficiency fossil fuel system. A considerable volume of gas is consumed to hold the molten metal at temperature that is much lower than the flame temperature. This will lead to more effort and energy consumption to capture the excessive production of the CO₂. The concern of this study is to investigate the feasibility of the regenerative-burners’ furnaces to increase the furnace efficiency to reduce gas consumption per production and hence result in less CO₂ production. Energy assessments for metal holding furnaces are considered at different operation conditions. Onsite measurements, supervisory control and data acquisition data, and thermodynamics analysis are performed to provide feasible information about the gas consumption and CO₂ production as well as area of improvements. In this study, onsite measurements are used with thermodynamics modeling to assess a 130 MT rectangular furnace with two regenerative burners and one cold-air holding burner. The assessment showed that the regenerative burner furnaces are not profitable in saving energy, in addition to the negative impact on the furnace life. However, reducing the holding and door opening time would significantly increase the operation efficiency and hence gain the benefit of the regenerative technology.