Researchers from the Indian Institute of Science (IISc), under a multilateral project (Acronym 3D Printing), in an attempt to contribute towards sustainable construction, have pioneered breakthrough materials and processes that could bring down the building industry’s carbon emissions.
The Centre for Sustainable Technologies, IISc, has utilised 3D printable material formulations utilising industrial by-products, including construction and demolition wastes (CDW), blast furnace slag, and fly ash for carbon sequestration.
Uses in construction
These formulations have the potential to be used in fabricating walls, slabs, and various other building components.
According to the Department of Science and Technology (DST), the developed material, utilising an optimised process of accelerated carbonation curing, can store 35% to 40% of CO2 by mass of cement.
“The exact percentage depends on factors such as density, curing conditions, and mixture formulation. An additional benefit is the formation of small crystals of carbonate minerals during the sequestration process, which enhances the engineering performance of the material,” DST stated.
India’s cement and brick manufacturing sectors contribute a staggering 200 to 250 million tons of carbon dioxide (CO2) annually, a challenge that becomes ever more pressing as the country commits to achieving net-zero emissions.
Two critical goals
“The mission to realise sustainable, low-carbon construction depends on two critical goals: reducing the reliance on mined resources and curbing the CO2 emissions inherent in material production, known as embodied carbon. At the forefront of this innovative endeavour lies the concept of accelerated carbonation curing. This process leverages CO2-rich industrial flue gases to mineralize carbonates within construction materials, creating a stable and permanent means of CO2 storage,” states DST.
This advancement on the 3D printed materials could serve as a sustainable substitute, capable of replacing up to 75% of natural sand in cement-based construction materials.
DST said this innovation offers a pathway to reduce the reliance on energy-intensive steam curing and minimise the extraction of mined resources, including natural aggregates and Portland cement.
