First project (re-use of AAC panels): a second life for our building materials

The first tests for this started in spring 2021 in our laboratory in Burcht, Belgium, to check the load-bearing capacity of used Hebel wall panels. The result: the load-bearing capacity does not suffer because of use. "This implies that the panels can be re-used to their total length or to a length reduced by maximum 7,5% of its original dimension," explains Kristof Desoete, Technical Advisor at Xella Belgium.

This project was also introduced as a Xella Innovation Project from NWE in 2021 and was turned into an Internal Release Project with a relation to the series of Circular Economy Projects of Xella Innovation Team. Material properties such as compressive strength, bulk density, mineral phase content, visual assessment and corrosion protection of the reinforcement will be determined in Brück or Emstal in the following months. Based on the results, an internal release document by Xella could be established for the client.

Second project: the recycling of AAC

A different strand to achieve more material efficiency for greater sustainability is the reprocessing of old materials into new ones. In a funded project with external partners such as the Colruyt Group, Vito and Chap-yt, Xella Belgium started a project to analyze the recycling process of AAC panels from demolition towards new AAC. Colruyt Group has taken the initiative for the project. Chap-yt is a company who recycles AAC waste into screeds for many years.

The project started in November 2021. Until November 2023 and with the help of the research institute VITO it should be possible to determine the acceptance criteria for Xella to use the AAC residues for the production of new AAC blocks in Burcht. The financial impact during the whole chain is also going to be analyzed in the project. "It is important to really evaluate the costs of processing the material so that it can return to the AAC production process,", says Elly Van Overmeire, Head of Product Management at Xella NWE and Innovation Manager at Xella NWE.