Extraction and use of raw materials
The first step consists in providing the requisite materials and energy. This is usually done by extraction and conversion of natural resources. For example, prior to steel production proper, iron ore has to be extracted and the production of plastics requires crude oil.
Material flows and resulting waste flows are fundamental parts of all production processes. The better the management of these material flows works, the cheaper as well as environmentally sound material intensive process steps are running of.
