Steelmaking is one of the most important processes in the industrial sector all over the world. Steelmaking results in the production of steel from iron ores, which is used for a variety of purposes ranging from construction of roads, railways, infrastructures, automobiles and buildings. Even the most innovated TMT reinforced steel bars like the Fe 415, Fe 500 etc are developed from the steelmaking process. The demands for steel are always increasing to the point that we cannot imagine a world without steel.
Steelmaking methods have been ongoing since the late 19th century. As newer technologies developed so did the steelmaking methods. The Bessemer process was the first inexpensive industrial steelmaking process. The modern methods, however, are still based around the Bessemer Process, mainly on how to efficiently use oxygen to lower the carbon content in iron.
Even though the steelmaking process helps the environment by recycling, which includes the usage of steel scraps, Steel production has certain negative impacts on the environment. The root cause of all these environmental issues stems from coking and ironmaking process.
These hazards typically include emissions by gases such as CO, SOx, NOx, liquid wastes and solid wastes. The following lists the impacts on environments caused by steelmaking.
Climate change: Carbon dioxide emissions are the by-products in steelmaking, due to the higher amount of carbon dioxide in the atmosphere, it leads to the greenhouse effect, which in turn creates climate changes.
Air pollution: Coke is one of the principal materials used in steel production. It is produced by the heating of coal. Naphthalene, ammonium compounds, sulfur and coke dust are emitted from coke ovens and is the source of major air pollution.
Water contamination: Water is normally used to cool the coke after it has finished manufacturing. The water used for quenching becomes contaminated with coke breezes and other compounds. While the volume of contaminated water is great, the quenching water is easy to reuse. Most of the pollutants can be removed by the filtration method.
Wastes: limestone and iron ore impurities usually consists of the largest portion of steel making by-products. These waste products are collected at the top of the molten iron. Sulfur dioxide and the hydrogen sulfide gases are volatized and captured in air emissions control equipment and the residual slag is sold to the construction industry.
Although steelmaking has these aforementioned problems, it doesn’t stop the production of high-quality steels, which is why alternative and more environment friendly measures are being developed. Also by using recycled steel scraps, it also helps in minimizing the damages caused to nature.