Canadian Welding Bureau (CWB) Level 3 Practice Exam

The best way to extract iron from its ore industrially is by smelting in a blast furnace using coke as fuel and reducing agent. In that setup, coke burns in a hot blast of air to form carbon monoxide, which chemically reduces iron oxides in the ore to metallic iron. This reduction happens at high temperature and is aided by adding limestone as a flux to form slag, which removes impurities. The outcome is liquid iron (pig iron) at the bottom with slag floating on top.

Other methods aren’t practical for bulk iron production from ore. Electrolysis in a molten bath requires enormous energy and is not economical for iron extraction. Direct reduction in an electric arc furnace is typically used for producing steel from direct-reduced iron or scrap rather than extracting iron from ore itself. Heating ore with hydrogen gas could technically reduce iron oxide, but it’s not the established industrial method due to cost and process considerations.

So, the coke-based blast furnace route best explains how iron is extracted from ore in industry.