NTPC invites EoI to build fly ash-based roads at its plants

NTPC has invited expression of interest (EoI) for construction of fly ash-based geopolymer concrete roads at its plants to demonstrate use of this technology, a company official said.

"NTPC has invited players to construct fly ash-based geopolymer concrete roads. About 1,100 tonne of fly ash is used per km of geopolymer road," the official told PTI.

Earlier, the company has successfully completed similar project at Dadri station as per Indian Roads Congress (IRC) specifications & accreditation. Moreover, 1.2-km double lane stretch are being constructed at Ramagundam and Farakka stations. These projects are being developed by NETRA, the R&D wing of NTPC.

NETRA has also developed geopolymer concrete spun / hume pipes, tetra pods, tiles and is working on other applications as well.

Geopolymer concrete, an eco-friendly construction material, is a 100 per cent replacement of cement and has a great potential as a binder as it sets to a material and gains strength more rapidly than Portland cement.

Geopolymer concrete has emerged as an important engineering material in recent times because of its utility in developing ecologically sound and sustainable construction materials.

Concrete demand is expected to grow to 18 billion tonne per year globally by 2050. Portland cement is not only energy intensive but also responsible for large scale emission of CO2, the official added.

During 2017-18, 32.23 million tonne of ash, which is 53.45 per cent of the ash generated, was utilised for various productive purposes by the company.

Other important areas of ash utilisation are cement & asbestos industry, Ready Mix Concrete plants (RMC), road embankment, brick making, mine filling, ash dyke raising & land development.

The new initiatives for use of fly ash, like geopolymer road, transportation of ash from pithead power stations to fly ash consumption centres, setting up ash-based light weight aggregate plant etc, are being explored by NTPC, the official said.