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A Rolling mill. You can see the steel being cooled with a continuous water spray. Steel mills use tens of millions of gallons of water each day.

Steel production takes a lot of water. Water is a crucial component in industrial steelmaking processes, primarily used for cooling and as a medium for various chemical reactions. Steel has a melting point between 2500 and 2800°F or 1371 and 1540°C, and as you’d expect it would take a long time for a newly completed steel beam to cool down.

Water is extensively employed for cooling purposes in steel plants. High temperatures are generated during various stages of steel production, such as blast furnace operation, steel casting, and rolling. Water is circulated through cooling systems to dissipate heat and maintain equipment and materials at appropriate temperatures. This prevents machinery from overheating and ensures the quality of the steel. But heat isn’t the only problem steel manufacturers have to deal with. Steelmaking processes often generate dust and particulate matter, which can be harmful to both workers and the environment. Water is used to suppress dust by spraying it on materials and surfaces. This helps in keeping the workplace clean and reduces the release of airborne pollutants.

Steel manufacturers aren’t going to let any material go to waste. In recycling and secondary steelmaking, scrap metal is washed with water to remove contaminants, dirt, and other impurities. This ensures that the steel produced from recycled materials meets quality standards.

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Wastewater trap at a steel mill. The water is contaminated with all manner of metals, heavy metals, hydrocarbons, and mill scale.

Water isn’t just used in physical processes. Water is involved in various chemical reactions within the steelmaking process. For instance, water vapor is used in the reduction of iron ore in a blast furnace, where it reacts with carbon to produce carbon monoxide and hydrogen gases. These gases are essential for reducing iron ore into molten iron. Steel plants also employ water in gas cleaning processes to remove impurities from exhaust gases. Scrubbers and filters use water to trap pollutants, making the emissions less harmful to the environment. But leaving the water in need of treatment.

Some steel plants use generated steam as a source of energy for various processes. Water is heated to produce steam, which can drive turbines and generate electricity for the plant’s operations. Water can also run hydraulic systems used in steel mills to power heavy machinery, such as rolling mills and forging presses. These systems provide the necessary force for shaping and processing steel.

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Wastewater exiting the steel mill. This concrete trough traps some of the mill scale that was washed off during forming.

It’s important to note that the use of water in steelmaking also has environmental implications, such as water consumption and wastewater management.

IX Water is working with steel plants to treat water to a higher standard than it was received and reusing that water in closed-loop systems. This reduces the impact of steel production on the environment while still providing the steel needed for modern society.

Water plays a substantial role in industrial steelmaking, from cooling and dust suppression to chemical reactions and environmental management. Its efficient use is essential for ensuring the quality of steel products while minimizing the environmental footprint of the industry.