Steel is a product of naturally occurring iron ore or repurposed scrap that is melted down. To begin steel production, iron ore is smelted in a blast furnace, impurities are removed, and carbon is added resulting in liquid steel. If scrap is the source, it is melted in a blast furnace so that it can be reused. Raw steel can be formed, molded, or rolled into any shape needed for end products. The main function of water in a steel mill is cooling. Water is utilized to cool blast furnace walls, steel molds, casting machines, and hot rolling machines. Additionally, water is used for cleaning of steel products and for steam power generation.