高炉 (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. The process results in the production of pig iron, which can be further refined into steel. The high furnace is a crucial component in the iron and steel industry, contributing to the production of materials used in construction, manufacturing, and various other applications. Its efficiency and design have evolved over time, making it a key technology in metallurgy.