Worldwide, over 400 million tonnes of metal is recycled each year.
Virtually all metals
can be recycled into high quality new metal.
The process varies for different metals, but generally produces
metals of equivalent quality. Thus, for example:
• Steelmaking using the electric arc
furnace process uses scrap metal as the major raw material. This
method is typically used for high quality tool steels and stainless
steel. Smaller quantities of scrap can also be used in basic oxygen
(blast furnace) steelmaking.
• Copper scrap is used by both primary and
secondary producers, where processing methods include blast furnace,
reverberatory furnace or electric arc furnace. In the latter, around
75-80 per cent raw material is scrap copper.
• Aluminium production uses a single
production method - the Hall-Héroult Process. But virgin raw
materials require temperatures of around 900 C, whilst scrap
aluminium melts at around 660 C.
Metals recycling protects the environment and saves energy. Using secondary raw materials means less use of natural resources which would otherwise be needed to make new metal compounds – such as iron ore in steelmaking; nickel in stainless steel; or alumina and bauxite in aluminium smelting. There are also considerable savings in energy, and reduced CO2 emissions, in production methods using recycled materials: