Towards a sustainable decision framework with harmonized metrics for circularity and life cycle assessment in manufacturing

Sustainable design and environmental optimization of processes over the last years became an essential part of industrial development. The transformation of complex industrial processes requires standardized methods which consider applicability and compliance for companies. In the context of sustainable development, measures need to consider the three dimensions of sustainability and interrelations between them. This chapter thereby presents a first step towards the creation of a sustainable decision framework which combines assessment methods for all three dimensions. The research within this chapter is focused on the environmental dimension and investigates methods for combining the assessment of the environmental impact and circularity of material flows. While life cycle assessment (LCA) is an accepted and standardized method for evaluating the environmental impact, circularity assessment (CA) still lacks standardization. Lastly, the trade-offs between the different metrics are just recently being investigated in scientific research. A number of decision methods were identified that are able to combine results of CA and LCA. The respective CA metrics were further examined to representatively show potential applications. Lastly, requirements for harmonized CA and LCA in the environmental dimension are summarized and generic requirements for a sustainable decision framework with metrics for all three dimensions of sustainability derived. This research thereby contributes to the development of a sustainable decision framework based on standardized methodologies and data that supports holistic and knowledge-based decision-making in manufacturing companies.