From waste glass to glass foam: scale-up of innovative recycling process through life cycle analysis

Solving environmental critical issues is at the center of international policies which increasingly seek to support and promote sustainable development. Circular economy (CE) aims to close the life cycle of a product by favoring recovery and recycling options. The design phase of a product is essential to avoid the production of waste and to have sustainable and circular development. Market is looking for innovative solutions not only from an economic but also a social and environmental point of view. Sustainability-oriented innovation (SOI) considers the need to include a long-term time horizon, examines the problem with a life cycle approach and considers multidimensional objectives. The University of Padua has created an innovative process to obtain glass foam from glass waste through the alkali activation. Starting from the Life Cycle Assessment (LCA) conducted on the small-scale plant, the research aims to understand the environmental criticalities of the industrialization. The sensitivity analysis is applied by exploiting the use of primary data integrated with the data available in the Ecoinvent database and using the ReCiPe 2016 impact assessment method through the SimaPro software. Distances and the energy sources were changed to evaluate the scale-up. Industrialization should consider process optimization in order to reduce energy consumption rather than changing the source. Results demonstrate the validity of sensitivity analysis as a useful tool for optimizing recycling processes. Modifying some variables - already in the design phase – make it possible to choose the best innovative option from an environmental point of view.