WE.3.C || Benefits of Retaining Materials and Their Quality in a Circular Economy – Case studies

Guiton, Mélanie; Bertrand, Alexandre; Ehlert, Christina

The deconstruction of buildings bears a high potential for reuse and recycling of materials. As various European countries, Luxembourg has a special interest for minimising land occupation from waste disposal and to further preserve mineral, metal and fossil resources use in the construction sector, in relation to its Circular Economy strategy released in early 2021 by the government. Demolition waste management in practice is often not fully optimised because of technical and economic constrains, possibly resulting in considerable environmental impacts. Based on a pilot case, the building Jean Monnet I in Luxembourg that was recently deconstructed, Life Cycle Assessment (LCA) has been applied in order to demonstrate how far a selective deconstruction approach develops potential for resource-efficient and low impact valorisation options, for various waste material fractions. It was shown that a selective deconstruction mode is beneficial in terms of environmental impacts for some waste materials such as aluminium and wood. For other waste fractions – concrete, glass, plaster, glass wool – environmental gains from valorisation were moderate. LCA was completed with circularity assessment relying on a set of existing indicators. The objective of this presentation will be to discuss how the combination of LCA and circularity indicators can contribute to the definition of an optimal circularity strategy for demolition waste recovery at the local level. Room for improvement will also be demonstrated especially the need to better characterize the quality of materials along their recycling loops into inventory modelling and the importance to consider economic constrains from industrial stakeholders influencing demolition waste recovery and valorisation.