Iron ore, coke, and limestone are loaded into the top, while preheated air is blown into the bottom. It takes 6 to 8 hours for these raw materials to descend to the bottom of the furnace, where they are transformed into liquid slag and liquid iron. These liquid products are drained from the furnace at regular intervals. The hot air blown into the bottom rises to the top in 6 to 8 seconds, undergoing numerous chemical reactions.

Once started, a blast furnace operates continuously for four to ten years, with only short stops for planned maintenance. Pig iron is the intermediate and first product of iron making, reduced from iron ore. It has a high carbon content, typically 3.5-4.5%, along with silica, manganese, sulfur, phosphorus, titanium, and other trace elements.