We use this term to a process where an used resource (waste) can be used instead dispose it to the environment without gaining any value from it. Recycling can be used to simplify this term. There are several way to recycle either material or energy of waste. Beside metal which easily can be recycled to make a new metal, inorganic and organic waste can also recycled to recover either the energy contained in it or the material itself.
In order to recover organic waste anaerobic digestion where microorganisms degrade wastes in an absence of oxygen producing valuable methane which can be used as a fuel or composting where microorganisms degrade wastes in an existance of oxygen producing a valuable compost are usually used to recover organic wastes. In order to recover the energy contained in inorganic waste such as plastic incineration producing electricity and heat can be used.
