Valorisation of heterogeneous industrial residues towards a circular economy : A systems-oriented investigation on how to facilitate shredder fines valorisation in the Swedish context

In the context of circular economy in the European region the role of the recycling industry has become ever important. Shredder fines (or fines) is a heterogeneous fine-granular production residue of the shredding industry, and is currently disposed of. Shredder fines presents a disposal problem and incurs handling costs to the shredding industry. More importantly, its disposal reduces the resources efficiency of our society. This thesis aims to contribute systems-oriented knowledge to facilitate the valorisation of shredder fines in the Swedish context. In doing so, it contributes to two knowledge. Knowledge area one portrays the current picture concerning fines management in terms of the underlying factors of the current practice of fines management and the market prospects for secondary construction aggregates. Knowledge area two showcases the potential approach to initiate process development in terms of assessments of the resource potential of fines and the environmental impact of fines-valorisation. The findings of knowledge area one show that the studied shredding company is more inclined towards continuing on the current disposal-oriented management of fines. That is because of both incentives for utilising fines as landfill cover materials and disincentives for valorising fines, created by various policy, market, and organisational factors. On the other hand, a significant need exists to improve the prospects of secondary aggregates in the construction aggregates market. Currently, the market is chiefly characterised by processes and underlying structures that sustain dominant primary aggregates utilisation, whereas secondary aggregates utilisation is situational and driven by different supply chain actors due to different individual reasons. The findings of knowledge area two show that process development for fines valorisation has several technical and environmental challenges. The resource potential assessment of the fines shows that the initial technical feasibility of fines valorisation is considerable, however different resource recovery strategies would require different levels of processes for upgrading and resource recovery. The ex-ante life cycle assessment of fines valorisation shows that potential fines valorisation is environmentally more promising compared to landfill-related disposal, however, different resource recovery strategies would create different levels of environmental impacts and present different needs for improvements. Facilitating fines valorisation calls for different measures on the institution and actor levels. Drastic policy measures are required to remove the incentives for the disposal of the material and compel shredding companies to seek valorisation alternatives. In order to ensure long-term sustenance of fines valorisation, fines-derived secondary raw materials need secure outlets and clear market and regulatory playing rules for their generation and application. Additionally, environmentally feasible and cost effective upgrading and resource recovery processes have to be developed. The origin of circular economy is grounded in restoring the environmental balance and reducing the throughput of natural resources in anthropogenic systems. Nevertheless, the current conceptualisation of circular economy is predominantly focusing on the economic progress, which somewhat promotes “business as usual”. This thesis attempts to reinstate the original resource conservation idea of circular economy in relation to heterogeneous industrial residue valorisation.