Innovative Solution to Groundwater Contamination by IISc Researchers

Researchers at the Indian Institute of Science have developed a novel three-step method to remove arsenic from groundwater. The patent-pending process ensures safe disposal of heavy metals, preventing re-contamination. The technology, which has shown promise in lab and pilot-scale testing, could be highly effective at a community level.

Researchers at the Centre for Sustainable Technologies (CST), Indian Institute of Science (IISc), have developed an innovative remediation process for removing heavy metal contaminants like arsenic from groundwater.

This three-step method, pending patent, ensures an environment-friendly disposal of extracted metals, avoiding untreated waste that could re-enter water supplies, as detailed in an IISc release from Bengaluru.

"Most existing technologies extract arsenic but overlook safe disposal, risking re-contamination. Our process addresses this crucial gap," stated Yagnaseni Roy, Assistant Professor at CST, whose laboratory developed the method.

In response to concerning contamination levels, with 113 districts in 21 states having arsenic concentrations above permissible limits, the IISc team has introduced a sequence starting with contaminated water being passed through a chitosan-based adsorbent bed. This novel bed, combined with bimetallic hydroxide components, captures the toxic arsenic electrostatically.

The subsequent steps involve a recyclable alkaline wash solution to cleanse the adsorbent bed and a membrane to concentrate arsenic prior to bioremediation. Microbes from cow dung convert the toxic inorganic arsenic to less harmful organic forms within eight days, allowing safe landfill disposal of the residual sludge.

"These organic arsenic compounds are about 50 times less toxic than their inorganic counterparts," Roy emphasized.

This versatile system can also remove fluoride, replacing the bioremediation step with precipitation to generate calcium fluoride. The technology's efficiency was demonstrated, producing safe drinking water for two adults over three days from a pilot-scale column.

Collaborative efforts with NGOs, such as INREM Foundation and Earthwatch, have facilitated trial deployments in rural Bihar and Karnataka. The system's community-level application promises easier maintenance and operation, creating local employment opportunities, according to CST PhD student Rasmi Mohan T.

While funding might be necessary for broader deployment, the technology represents a significant advance in sustainable water purification.

(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)