Environmental Impacts of the Iron and Steel Industry
Carbon Dioxide Emissions
The iron and steel manufacturing processes generate significant quantities of carbon dioxide. As the production of steel relies heavily on iron, this greenhouse gas is released during the reduction of iron ores in blast furnaces and sponge iron factories. Additionally, CO2 emissions arise from the combustion of fossil fuels used in heating processes. Notably, coal used for energy generation accounts for approximately 90% of carbon dioxide emissions.
Nitrogen Oxide Emissions
Nitrogen oxides are produced in facilities that utilize coal, electric arc furnaces, and heating furnaces. Given that the iron and steel industry operates at high temperatures, the presence of nitrogen in the atmosphere makes it challenging to avoid the formation of these oxides.
Sulfur Dioxide Emissions
The emissions of sulfur dioxide are directly linked to the combustion of oil in heating furnaces, primarily for steel production purposes.
Climate Change
The increase in greenhouse gases, particularly carbon dioxide emissions from the steel manufacturing process, contributes significantly to climate change.
Slag Formation
Slag is defined as the by-products of limestone and iron ore resulting from the iron smelting process. This process also releases sulfur dioxide and hydrogen sulfide gases, along with the formation of slag, which is utilized in construction applications.
Mitigating Pollution from the Iron and Steel Industry
China stands as one of the world’s largest steel producers, and due to the adverse environmental effects of this industry, innovative technologies have been implemented to mitigate pollution. These techniques focus on the reuse of energy generated from waste in iron, coal, and steel manufacturing, including the rolling process. It is anticipated that these advancements will yield energy savings estimated at 220,000 tons per year.