BHUBANESWAR: A team of researchers from Institute of Minerals and Materials Technology (IMMT) claimed to have developed a process for transforming fly ash waste into wealth. They have claimed to have extracted commercially-useful minerals like alumina, impure quartz, calcium silicate and iron hydroxide containing rare earth elements from the ash. The process also aims to solve the problems related to disposal of fly ash.
Not just that, the researchers had also collaborated with experts from the Kolkata and Ahmedabad units of Central Glass and Ceramic Research Institute to transform calcium silicate, extracted from the fly ash, into ceramic cups. The impure quartz was turned into coloured glasses. But, as the researchers say, the main achievement was extraction of alumina, which could be used for manufacturing of aluminium metal, and the rare earth elements.
Led by Senior Principal Scientist in Hydro and Electrometallurgy Department of IMMT Sanjay Kali, the team was conducting the research at the institute’s laboratories since 2016 in phased manner. They had collaborated with National Aluminium Company (NALCO). For conducting laboratory tests, they had been procuring fly ash samples from Nalco’s thermal Plant in Angul. The researchers had also filed for patenting the process along with Nalco on January 12, 2006.
“From 1,000 kg of fly ash, we can extract 200 gms of rare earth elements. Around 25 per cent of the extracts is alumina, while 60 to 62 per cent is impure quartz and calcium or sodium silicate,” said Kali. The process was tested in bench scale at IMMT. But, the researchers are now trying to set up a pilot plant for greater extraction of rare earth elements. “We need huge quantities of fly ash for extracting substantial amounts of the rare elements,” he added.
On Friday, Coal Minister Pralhad Joshi lauded the process on social media. Reacting to a tweet by Rajya Sabha MP Ashwini Vaishnaw on IMMT technology to harness rare earth elements and other minerals from fly ash and stating that Coal India would be benefitted by it, Joshi tweeted, “Sure is an interesting concept of waste to wealth. @CoalIndiaHQ should collaborate with IMMT, Bhubaneswar for harnessing minerals from fly ash.”