BENGALURU: A pilot project involving an innovative wastewater treatment method, taken up by the Indian Institute of Science (IISc) in a primary school in Chamarajanagar district, is expected to provide clean water for sanitation for all by year 2030. It is expected to reduce the current dependence on fresh water by a significant 40 per cent.
IISc, through its Centre for Sustainable Technologies (CST), is part of an international initiative undertaken at the Beramadi Primary School in Chamarajanagar district. The IISc researchers are collaborating with their counterparts from a consortium led by the James Hutton Institute, University of Glasgow, Scotland, and the Ashoka Trust for Research in Ecology and the Environment (ATREE). The project is funded by the Scottish government to deliver a low-cost, decentralized waste water treatment system.
Dr Lakshminarayana Rao, assistant professor, CST, and lead researcher, is cited by an IISc release saying the choice of a rural primary school to house the plant was a deliberate one. “Rural schools in India have a mid-day meal scheme. There’s a lot of waste water coming from the kitchen and hand wash. It is low-hanging fruit because this water can be recycled to be used in toilets for flushing,” he explains.
Waste water, apart from that generated from toilets, is called ‘grey water’. Waste water containing faeces and urine — and therefore pathogens — is called ‘black water’. To recover grey water, the Berambadi pilot project uses plasma technology developed by Rao’s team at IISc. “We’re using a component of plasma to generate ozone, which disinfects the water,” he explained.
His lab has developed an ozonator which provides large volumes of ozone while ensuring that its energy demands are lower than conventional technologies. Rao explained that black water is treated before it is discharged by a multi-step anaerobic digestion process developed by Scottish water scientists. This ensures that groundwater is not contaminated.