This week Vicat announced that it was collaborating in a new consortium of manufacturers called the 'Advancement of Excellence in Industry' to advance decarbonisation, the circular economy, the factory of the future and the digital transition. To this end, it will construct a regional campus in Auvergne-Rhone-Alpes.

A key insight behind the initiative is that building circular economies can only succeed through collaboration, therefore more partnerships will need to be formed to achieve net-zero cement and concrete by 2050. Vicat and five other industrial companies, consisting of EDF, HEF Groupe, Rexroth, Sefim and SNCF, believe their businesses are complimentary and will work on innovative projects together to develop shared experiences and regional industrial hubs. The collaboration is expected to lead to decarbonisation and a circular economy with less waste and material shortages while the digital transition will support these challenges.

The reuse of building materials
Cement has used the industrial by-products of other industries such as the power sector and steel industries for many years for supplementary cementitious materials (SCMs), as well as plastic and solid waste in alternative fuels. Now the aim must be to accelerate the reuse of materials to lower CO2 emissions and waste not only at the plant – with SCMs, co-processing and CO2 capture and energy efficiency – but throughout the lifetime of the manufactured cement and the structures it creates.

The Global Cement And Concrete Association (GCCA) includes the reuse of building materials in its low carbon roadmap, which it argues it is necessary to avoid the depletion of natural aggregate resources. It also recognises the potential role of "design for disassembly" that looks to improve the efficiency of deconstruction and demolition, and will provide opportunities for recycling concrete. More construction and demolition waste needs to be recycled and used in new buildings and concretes. Products like SmartCrusher BV enable the break-up of concrete into the constituent materials of sand, gravel, and reacted and unreacted cement.

Building a world free from pollution and waste is the vision of the Ellen MacArthur Foundation (EMF). It states that in the EU alone, construction and demolition waste accounts for almost a third of total waste by weight. To make new buildings more efficient, they need to be designed with so-called embodied emissions of a building’s lifecycle and its reuse taken into consideration. EMF also makes the case for three-dimensional printing of concrete, which can reuse materials from demolition waste, as well as the use of digital passports for construction components to support waste reduction and to protect building standards.

CEMBUREAU reports that development is already underway to establish an end use of the fine crushed particles from concrete as a secondary raw material in clinker production. However, 'downcycling' refers to some recovered concrete that lacks the necessary characteristics to be re-used in similar structures or recycled to produce liquid concrete. Downcycled concrete would need to be crushed to a specific size and used as aggregate in new structures such as road stabilisation and building foundations, pavements and erosion barriers. 

More to explore
Exploring circular economies around the uses of concrete and cement to reduce embodied carbon of buildings and cities requires further investment and research. CEMBUREAU has outlined the importance of promoting industrial symbiosis and the recognition of energy recovery as a waste management solution for non-recyclable waste. The transport of materials and the distances involved also have to be considered in creating circular economies that have lower CO2 emissions. Moreover, governments will have a significant role to play in incentivising the reuse and recycling of building materials and improving regulations.