When ores are mined or refined into metal products, they are, by definition, unsustainable. That is because the amount of ores on the earth is fixed. Used metals such as iron, steel, aluminium, lead, copper, and zinc, however, are renewable. Therefore, the continuing depletion of mined metals can be avoided when recycling is practiced instead. Some of the issues related to mining can be circumvented too. One of these threats is acid mine drainage.
The Danger of AMD
Acid mine drainage (AMD) is a current contaminant of surface water in Australia. AMD develops from both abandoned and active mines and degrades a large number of streams annually. This degradation can lead to the death of aquatic life. In addition, AMD leads to the restriction of water use for recreation as well as for manufacturing and potable water supplies.
The mining of metals also leads to rock waste, known as tailings. When minerals are mined, the portion that is valuable is found in the ore, or the matrix of the rock. Once the ore is stripped, it is piled into tailings. Tailings can accumulate in large quantities, sometimes taking the form of ponds or large piles.
Tailings Are Hazardous
Tailings that are left as large piles can trigger a number of environmental problems including landslides, hazardous dust, and leaching, which leads to water pollution. Not only that, the tailings from uranium or copper mining can produce a sizeable amount of radioactivity.
Tailing ponds also carry the potential for environmental dangers including dam collapses; leaching, which lead to groundwater pollution; and wildlife fatalities. So, whether tailings are represented by piles or ponds, they carry hazardous risks – risks that make metal recycling in Perth all the more important.
When you review how the metal scrap recycling industry benefits manufacturers, you can see even more clearly why a recycling program is a sensible and reliable means of repurposing metals for everyday use. For instance, recycled steel is used for the production of doors, hoods, and other assemblies on cars, and repurposed copper is used for plumbing pipes and electrical wiring. That is why scrap metals are known as scrap commodities.
Recycling scrap metal also lowers the emission of greenhouse gas as the gas is produced during the smelting of virgin ore. In fact, the energy savings that are realised by using recycled metal over ore are quite significant. Calculations show the savings are 92% for aluminium, about 90% for copper, and 55% for steel.
The energy savings that are realised for recycling are impressive, especially when you compare that number to the energy used for producing ore in large production facilities. Because metal recycling conserves natural reserves, statistics show that recycling a single ton of steel can conserve stores of iron ore in the amount of 1,134 kilograms and coal and limestone in the amount of 635 kilograms and 54 kilograms, respectively.
In addition, the amount of energy that manufacturers save by recycling steel is enough to power around 20 million homes annually. Not only that, the recycling of aluminium, on average, preserves about 15 megawatt hours of electricity and as much as 8 tons of mined bauxite ore. Needless to say, you cannot overlook the contributions made by the scrap metal industry today.