National Metallurgical Laboratory (NML) has developed here, through a new technique, an ultra-strong variety of cement from fly ash, according to director SP Mehrotra.
“We think we have something unique. We are trying to exploit it and are in touch with some cement manufacturers in the country,” said Mehrotra.
Indian fly ash has been found to be suitable for geopolymerisation owing to its silico-aluminate nature and low calcium oxide content.
NML, using mechanically activated fly ash, has thus developed high-strength geopolymer cement that hardens and is ready to be used in 24 hours.
The cement is 120-MPs (mega-pascals) strong, which is significantly higher than that normally produced by the industry.
“This strength has not been reported by any cement producer so far,” said NML’s head of business development & monitoring (BDM), Swatantra Prakash.
Last year, NML developed technology for producing low-cost fly ash-based glazed tiles.
Lafarge India is among the leading manufacturers of fly ash-based cement in the country. It’s plant here produces around 3.1 mt of portland pozzolona cement (PPC) using the fly ash generated by Tata Power’s units here.
The new NML technology, however, apart from using geopolymers, will consume more fly ash per tonne of cement manufactured than currently being used by the industry in making PPC.
According to Prakash, the laboratory is currently busy trying to locate a public or private sector sponsor that will fund a 1-2 tonne capacity pilot plant of the ultra-strong cement project.
“The partner may either commercialise straightaway or go for the pilot plant,” said Prakash. He said NML has already approached a few organisations as regards this.
Ultra-strong cement could be used for making heavy-duty roads, tarmac, bridges, etc.
