A blast furnace is a large industrial structure used to produce iron from iron ore. It operates by combining iron ore, coke (a form of carbon), and limestone, which are heated to high temperatures. The intense heat causes the iron ore to melt, separating it from impurities, and the resulting molten iron can be collected at the bottom of the furnace. The process involves blowing hot air into the furnace, which fuels the combustion of coke and generates the necessary heat. This method is essential in the steel-making industry, as it provides the raw material for creating various steel products used in construction and manufacturing.