Recycling is the process of converting waste materials into new
materials and objects. The recovery of energy from waste materials is
often included in this concept. Recycling can prevent the waste of
potentially useful materials and reduce the consumption of fresh raw
materials, thereby reducing: energy usage, air pollution (from
incineration), and water pollution (from landfilling). Recycling is a
key component of modern waste reduction and is the third component of
the "Reduce, Reuse, and Recycle" waste hierarchy. Thus,
recycling aims at environmental sustainability by substituting raw
material inputs into and redirecting waste outputs out of the economic
system.
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