高爐, or "blast furnace," is a large industrial structure used for smelting iron ore to produce molten iron. It operates by combining iron ore, coke, and limestone, which are heated to high temperatures. The coke serves as a fuel and reducing agent, while the limestone helps remove impurities from the iron. The process in a 高爐 involves layering the raw materials and blowing hot air into the furnace. This creates a chemical reaction that separates the iron from its ore. The molten iron produced can then be cast into various shapes or further processed to create steel, a vital material in construction and manufacturing.