Researchers have devised a technique that uses construction and demolition waste (CDW) and alkali-activated binders to create energy-efficient walling materials. These low-carbon (low-C) bricks don’t need to be fired at high temperatures, and they don’t need high-energy components like Portland cement.
Key Highlights
- Researchers have devised a technique that uses construction and demolition waste (CDW) and alkali-activated binders to create energy-efficient walling materials.
- These low-carbon (low-C) bricks don’t need to be fired at high temperatures, and they don’t need high-energy components like Portland cement.
- The construction industry in general, and the building sector in particular, will be the primary beneficiaries of this progress.
- The Department of Science and Technology provided funding for the project.
BENGALURU: Indian Institute of Science (IISc) researchers have devised a technique that uses construction and demolition waste (CDW) and alkali-activated binders to make energy-efficient walling materials.
The team names these low-carbon (low-C) bricks since they don’t require high-temperature burning and don’t employ high-energy components like Portland cement. Researchers anticipate that the method will also alleviate disposal issues related with building and demolition waste minimization. The Department of Science and Technology provided funding for the project (DST).
Prof Bv Venkatarama Reddy, the team’s leader, stated that with IISc’s technical assistance, a start-up will be operational in six to nine months to make low-C bricks and blocks. The start-up unit will serve as a technology dissemination unit, providing training, capacity building, and technical know-how for creating similar commercial units across India,” said Reddy, who just retired from IISc.
The construction industry in general, and the building sector in particular, will be the primary beneficiaries of this progress. This technique will also help to alleviate the CDW’s disposal issues. DST pointed out that traditional building envelopes are made up of masonry walls made up of burnt clay bricks, concrete blocks, hollow clay blocks, fly ash bricks, lightweight blocks, and other materials that use energy to manufacture, emit carbon (i.e., have embodied carbon), and consume mined raw material resources, resulting in unsustainable structures. The masonry units are made either by a fire process or by employing high-energy/embodied carbon binders like Portland cement. According to the DST, India consumes over 900 million tonnes of bricks and blocks each year. “In addition, the construction industry generates a large amount of CDW (70-100 million tonnes per year).”
Two major challenges must be addressed during the manufacturing of masonry units in order to encourage sustainable construction: the conservation of mined raw material resources and the reduction of emissions. IISc scientists developed a technology for making alkali-activated bricks/blocks using fly ash and furnace slag to achieve this goal, according to the DST. The researchers determined the ideal mix ratios of ingredients before evolving the production process to make low-C bricks after determining the physico-chemical and compaction characteristics of the CDW. “The compressed bricks were made using the optimal binder proportions. The DST stated that the bricks were inspected for engineering qualities.
