Developing sustainable solutions for the cement industry

Since the introduction of Portland cement around 200 years ago, our built environment is now outgrowing the natural environment that has existed for millions of years. 

This is driven primarily by rapid urbanisation. By 2050, 80 per cent of the world’s population is expected to live in cities. Decarbonising industry would provide the best possible chance for humanity to mitigate the effects of climate change. Consequently, we need to rethink the way we build our cities.

Cement is the durable, waterproof and ubiquitous material upon which modern civilisation is built. However, cement production alone accounts for around 8 per cent of global CO₂ emissions. Half of these result from chemical reactions inherent in the production process, so there is tremendous demand for sustainable cements with low-CO₂ embodiment.

Shifting completely to sustainable cement could save up to 2.75 billion tonnes of CO₂ emissions annually - equivalent to 6.2 per cent of global CO₂ emissions. Many low-CO₂ cements generated from industrial waste or by-products have emerged as attractive, more sustainable alternatives to traditional Portland cement.

Industrial implementation of these low-CO₂ cements has been slow, however, due to difficulty in controlling reaction, setting and hardening of these cements, due largely to variation in physical and chemical characteristics of raw materials used. Chemical engineers are working hard to understand the fundamental fluid-particle interactions, reaction mechanisms and kinetics, and composition-structure-property relationships, to design new tailored sustainable cements for demanding applications.

Dr Brant Walkley, Department of Chemical and Biological Engineering, explains, "We use thermodynamic modelling to understand the long term phase assemblage and performance of sustainable cements in industrially relevant conditions, investigate organic-inorganic interactions to design additives for sustainable cements, and study nanostructural evolution to enhance durability."

"As a community, chemical engineers are uniquely placed to drive revolutionary change towards sustainability within the cement and construction industry. The solutions are within reach, and together we can make a difference."