The use of pozzolanic waste materials in concrete is increasing significantly due to the environmental and economic benefits that follow.

Recently, one waste product that has shown promise is foundry sand.

Foundry sand is a high-quality silica sand, used traditionally in the metal casting process, and is now being used to create ‘green concrete’.

The advantage of using a pozzolan such as foundry sand is that it can enhance the properties of concrete, improving its durability, strength, and resistance to environmental factors.

The challenge facing developers is in the transformation process, with innovation required to turn this casting agent into a pozzolanic material.

The recent developments in milling technology, have allowed foundry sand to be micronised, making it a suitable additive for concrete mixtures.

Repurposing this foundry sand considerably reduces the need for landfill disposal, assisting in effective waste management and simultaneously reducing the carbon footprint associated with the transport and landfilling processes.

Economically, using foundry sand can substantially diminish the costs of concrete production.

As it is readily available as a by-product, foundry sand can be a more cost-effective alternative compared to conventional pozzolans.

Incorporating this pozzolan can boost the mechanical properties of the mixture, resulting in concrete with enhanced compressive strength, superior workability, and heightened resistance to environmental adversities.

Foundry sand also considerably reduces the CO2 emissions compared to ordinary Portland cement mix.

The growing potential for foundry sand will create new avenues for sustainable construction.

Ensuring rigorous research and the correct processing techniques are carried out, this waste material can contribute to the new developments in concrete and play a greater part in the circular economy.