BENGALURU: Eight students of CMR Institute of Technology here have won gold medal for their project on the use of fly ash to rid dying lakes of pollutants and restore their health.The recent Indian International Innovation Fair, held in the city, recognised their project as an out-of-the box solution.Their project offers a solution to two issues plaguing Bengaluru -overflowing plastic garbage and polluted lakes: fly ash can be used to treat Bengaluru's polluted lakes and it can be combined with plastic waste to manufacture flexible composite bricks.Fly ash is a byproduct of coal combustion generated by thermal power plants and cement factories. The fine grey particles transported by the wind and deposited in surrounding localities are known to cause or worsen respiratory disorders and make soil infertile Second and third-year students from different departments - Nithin Kumar V , Pranav Bhat, Sudarshan MS, Gururaj R, Vinay Kumar BA, C J Anoop, Pavan R Reddy , Naren M -have collaborated on this project and won several accolades.When Karnataka State Pollution Control Board chairman Lakshman inspected the dying Varthur lake last week, he interacted with the team.“He said they will consider using the method to treat the highly polluted waters of the lake and asked us to conduct further tests,“ said V Nithin Kumar, a second-year ECE student.The idea was born around this time last year. During a chapter on water technology , students were looking for solutions to the city's polluted lakes.Kumar said, “It is known that fly ash can adsorb heavy metals and organic matter present in a solution.“ The team tested it with a sample of water from Bellandur lake and found that the brownblack water became clear and did not smell anymore.“About 100 ml of water can be clarified in five minutes by adding onetenth fly ash. When speeded up using vacuum, it can be done in a matter of seconds,“ Kumar explained.A simple filtration then separates the fly ash and other pollutants from the water. Combine this with waste plastic to make bricks and the result is a highly flexible brick that can better withstand tremors.“These bricks can be used in noncritical constructions such as walls and temporary army camps. We hope to implement these ideas and take them to the market,“ said CJ Anoop, a third-year student of Information Science.While it is a promising proposition, it may not be practical to implement.Professor TV Ramachandra, Coordinator of Energ y and Wetlands Research Group at IISc, while appreciating the work of the students, said, “as fly ash does not absorb all nutrient content, it may not be the right method of purification for large water bodies such as lakes. It can be useful in smaller and specific purposes such as treating effluents within a factory or in industry dry-cleaning.“The team has already signed an agreement with an apparel manufacturer to use this method to treat the effluents.