KANNUR: Nobody must have thought about obtaining Geopolymer concrete mix and aggregate from industrial waste. The end product is arguably stronger than cement. And moreover, there is a 12-15% reduction in manufacturing costs. The manufacturing method developed by the research team at the Kozhikode National Institute of Technology has now been patented. If opted for industrial use, geopolymer concrete could become the new alternative for cement.

The experiment was part of P Saranya's Civil Engineering PhD. Saranya is a native of Kannur Mathamangalam. Dr. Praveen Nagarajan of the NIT Civil Engineering Department and A P Sasikala supervised the project. Saranya is a Project Scientist at IIT Chennai.

Geopolymer is resistant to acid, chemicals, seawater and is very effective for offshore construction. As water does not pass through, the rods made using geopolymer concrete will not rust. The water tank and building parts were constructed using geopolymer concrete blocks and after three years of observation, finally the patent was approved.

• While cement concrete takes 28 days to set, geopolymer concrete takes 7 days. No need to soak.
• Geopolymer concrete is made by polymerization of 70 % dolomite and 30 % GGPS with sodium hydroxide.

The name geopolymer was coined in 1978 by Joseph Davidovits, a French scientist who discovered polymer chemistry. Geopolymer concrete (GPC) can be made using fly ash from coal burning and granulated blast furnace slag (GGBS) from ore smelting to separate iron. Silicon and aluminium are abundant in fly ash and GGBS.