Waste stream characterisation for industrial symbiosis matchmaking: a case study for ferro metals

The increasing demand for materials is a barrier to achieving a truly circular value chain. As long as the demand increases, extraction of virgin material will remain necessary. Furthermore, as we keep injecting pure virgin material in our value chain, the impurities that are added along the different life cycle stages are diluted. For this reason the real consequence of current material use and reuse is still unknown. As we move towards a circular value chain, not only the volume of reusable resources, but also the quality of those streams becomes more important to monitor. There is a need to better characterize material streams in order to identify the possibilities in the short term and to estimate the consequences in the long term. In this paper relevant data are gathered to assess the potential for a truly circular value chain. First, the concept of industrial symbiosis, that is considered a key success factor to achieve a more circular value chain, is defined. In order to facilitate the link between companies generating and receiving waste streams, a uniform material characterisation method is mandatory. Therefore, the charaterisation of input streams for manufacturing processes is discussed in a second step. The paper focusses on metals because of their economic importance and their high potential for reuse. Taking into account its relative importance in mass volume, special attention is given to steel. In a third step available information of generated waste streams is discussed and current characterisation of metal scrap is reviewed. Currently information related to metal scraps is limited to properties relevant for furnace operators such as presence of tramp elements or maximum dimension to allow direct charging. To identify potential opportunities for industrial symbiosis matchmaking additional information is required such as transparent labeling of the composition of metal waste streams and the state in which they are available.