IISc researchers develop wastewater treatment and recycling system

Researchers at the Centre for Sustainable Technologies, Indian Institute of Science (IISc) Bangalore, have claimed to have developed a first-of-its-kind efficient, low-cost decentralised wastewater treatment.

A new study, published in the Journal of Water Process Engineering and carried out in collaboration with researchers in the UK, shows how the system has, over the past year, enabled the reuse of wastewater and reduced dependence on freshwater resources, IISC said in a news statement.

“We have demonstrated for the first time that decentralised wastewater treatment systems can be economically put into practice in a rural setting,” assistant professor at CST and a senior author of the paper, Lakshminarayana Rao, said.

The pilot project has come up at Berambadi primary school situated in the remote village of Berambadi, Karnataka. “The people of Berambadi village are very happy with the system. Based on the success of this sustainable wastewater management project, several other schools in Karnataka have approached us to duplicate it in their schools,” Rao said.

The research team operated the greywater treatment system for a year and monitored the physicochemical and biological characteristics of the greywater at the entry and exit points.

The next step involved monitoring performance at every treatment stage and quantifying it in terms of removal efficiencies (REs) of turbidity, Total Suspended Solids (TSS), nitrate, total phosphorus, Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and faecal coliforms (FC).

Overall, the system showed high REs more than 90 per cent for most of the parameters. About 667 litres of greywater was treated daily using the system, saving around 180,000 litres of water annually, IISc claimed in its statement.

Such a robust wastewater management system can be replicated in both rural and urban settings after taking into consideration various factors such as space limitations, baseline greywater quality and daily flow rates, the authors suggested explaining how the system works.