Researchers develop low-carbon bricks for energy-efficient buildings
Energy efficiency has a number of benefits, including a reduction in greenhouse gas emissions, a reduction in demand for imported energy, and a reduction in home and economy-wide expenses. The emphasis is on energy-efficient design and construction of energy-efficient buildings without sacrificing the residents' comfort. However, effective materials must be developed for this purpose.
The Indian Institute of Science (IISc) in Bangalore has discovered a process for manufacturing energy-efficient walling materials from building and demolition waste and alkali-activated binders. These are referred to as low carbon bricks since they do not require high-temperature burning and do not contain high-energy components like Portland cement. The technique will also address disposal issues related with C&D waste minimization, according to a statement released Thursday by the Ministry of Science and Technology.
Using fly ash and furnace slag, IISc researchers developed a method for generating alkali-activated bricks/blocks. They generated low-embodied carbon bricks from building and demolition debris by alkali activating them with fly ash and pulverised slag and then characterising their thermal, structural, and durability properties.
After determining the physicochemical and compaction properties of building and demolition debris, the optimal material mix ratios were determined, and the production procedure for low carbon bricks was evolved. Compressed bricks were made using the optimal binder proportions. The engineering features of the bricks were determined.
The masonry units are either fired or binders with a high energy/embodied carbon content, such as Portland cement, are used to make them. India consumes approximately 900 million tonnes of bricks and blocks per year. Additionally, the construction industry generates massive amounts of building and demolition trash (70–100 million tonnes per year).
“To encourage sustainable building, two critical challenges must be addressed during the fabrication of masonry units: resource conservation and emission reduction,” researchers stated.
“With technical assistance from IISc, a start-up has been registered that will be operational within six to nine months to manufacture low-carbon bricks and blocks. The start-up unit would serve as a technology distribution vehicle by offering training, capacity building, and technical know-how for the establishment of similar commercial units across India,” noted Prof. B V Venkatarama Reddy of IISc Bangalore.
Traditionally, building envelopes have been constructed using masonry walls made of burnt clay bricks, concrete blocks, hollow clay blocks, fly ash bricks, and lightweight blocks. The envelopes absorb energy throughout their manufacturing process, resulting in carbon emissions (i.e., they have embodied carbon). They also utilise mined raw material resources, resulting in unsustainable constructions.
The construction industry in general, and the building sector in particular, will benefit significantly from this research, which was funded by the Department of Science and Technology (DST) of the Government of India. Additionally, this method will alleviate disposal issues related with building and demolition trash. (Scientific India Wire)