The Different Environmental Effects of Recycling Steel
Various reliable sources concur that there are many environmental advantages of recycling scrap steel. The main advantages are as follows:
1. Energy and Resource Savings
Energy - Only 75% of the energy required to smelt iron ore is used in recycling scrap steel, saving electrical energy.
Resources – The quantity of water required in recycling steel is greatly reduced, as washing and enrichment of the iron ore is not required.
Landfill savings are made by the public when recycling their domestic scrap steel and further land savings being made in the extraction and processing of the ore. For every ton of steel recycled, nearly two tons of iron ore is saved, which means a reduction in the land to store the tailings of unwanted minerals and gangue.
The decrease in iron ore extraction allows further significant savings in land usage possible, especially if an open cast method is used. Reduction of coal and limestone, which are used in the blast furnaces, also result in significant land savings during their extraction and processing stages (similar to iron ore above).
2. Construction Industry - Many new houses and commercial buildings are being constructed using recycled steel for corrugated roofing, structural steel girders and beams, all of which at the end of their life are 100% recyclable without any detrimental effects on the base metal.
Water and Land Pollution – Iron ore extraction and processing pollutes the surrounding area through acids leaching into the ground and fresh water supplies such as aquifers, rivers and lakes. Recycling produces 70% less water pollution by reducing the quantity of iron ore extracted and processed.
Air Pollution – Overall savings of over 80% in air pollution are achievable by recycling steel against the primary smelting from iron ore.
Recycling steel using an efficient Electric Arc Furnace which incorporates a fume treatment plant, extracts most of the noxious fumes and particulates from the molten scrap steel. However, not all the pollutants are removed. Some materials left in the scrap steel, such as plastics and foam from automobile recycled steel, can create noxious fumes. These fumes can be emitted into the atmosphere and are currently under investigation by government environmental agencies. This pollution and subsequent legislation would not be necessary if more effort was employed in removing the plastics and foams at the materials sorting stage, before the remelt process.