Subproject: Material flows "built environment" - urban-rural linkages following mineral building materials
Demographic and structural change as well as migration patterns of the population lead to disparate developments in urban and rural areas. In the future, it is assumed that more mineral waste will be generated in rural areas than can be recycled there. An opposite development can be seen in the city, where there is a great need for and potential use of recycling materials, but not enough is available. Both trends must be taken into account and investigated in relation to each other. Up to now, mineral bulk building materials (sands, gravels) have received little attention in the analysis of urban-rural relationships, although there are shortages of various kinds of aggregates.
The aim of the overall project is to strengthen urban-rural relations by developing a sustainable circular economy for mineral construction waste fractions. The IOER is working on the sub-project "Material flows of the built environment" and quantifying these in case study regions (city of Dresden, Meißen district) with a focus on the material of concrete. Potential cycles in the building stock are analysed qualitatively and quantitatively, and the exchange relationships between city and countryside are analysed in order to promote sustainable regional concrete recycling. The following research questions will be answered:
The development of regional material registers for the city of Dresden and the district of Meißen is currently in progress, using the conceptual work on the set-up of regional material registers from the KartAL IV project but extended to include the area of "roads". The cadastre will thus include all elements of the built environment that essentially determine the stock and flows of mineral building materials: Domestic buildings, non-domestic buildings and roads.
Information on supply relationships between actors or locations of the recycling industry are integrated into analyses of networks of the local recycling industry in the framework of interviews, which will be followed by an analysis of transport distances.
Different products of secondary raw materials require specific processing technologies and corresponding areas where this processing takes place. This results in land requirements and potential land use conflicts for construction waste processing. Preliminary analyses have been completed. This represents an essential interface between material flow analyses and land management approaches, which will be further explored in the project.