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How does slag foam help protect the walls of an electric-arc furnace?

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How iron is turned into steel — iron processing Iron ore is one of the most abundant elements on Earth, and one of its primary uses is in the production of steel. When combined with carbon, iron changes character completely and becomes the alloy steel.

In an electric-arc furnace (EAF), slag foaming is a critical technique used to protect the furnace sidewalls from the intense heat generated by the electric arcs.

The process is initiated by injecting carbon or a lime-carbon mixture into the furnace. This material reacts with the iron oxide present in the slag to produce carbon monoxide gas. This reaction causes the slag to expand and create a foam that rises within the furnace. This layer of foam acts as a physical shield for the sidewalls, effectively burying the electric arcs and preventing them from directly overheating the furnace lining. By providing this protective barrier, the slag foam allows operators to utilize higher power settings during the melting process, increasing efficiency without damaging the furnace structure.1