In a circular economy, the materials used remain within a material cycle that extends beyond the life cycle of goods. The aim is to reduce waste, emissions and dissipative losses as much as possible, thereby minimizing the extraction of raw materials from the environment. Key elements for implementing a circular economy include reusing and recycling goods, recycling materials and substances, and designing goods in such a way that they can be recirculated without any loss of quality or accumulation of pollutants. As such, goods should be useable for as long as possible and then returned to the cycle as quickly as possible at the end of their useful life. One secondary constraint that has a significant impact on the quality of a circular economy is its energy demand; a high-quality circular economy requires the least energy possible — ideally from renewable sources — to maintain the cycle. Substances that cannot be recycled should be recovered as energy. Where dissipative losses are unavoidable, such materials should be degradable. The concept of the circular economy can be applied equally to regions, industries, companies and even individual goods.
Source
Hiebel, M.; Nühlen, J. (2017): Stahlschrott als Teil einer zirkulären Wirtschaft. In: Müll und Abfall, 2017(3), S. 118–123.