Absorb this: Indian-origin researcher in Toronto developing water-purifying sponge
The technology of using sponges to soak up contaminants has existed since the 1800s. Most people use them for everyday activities such as cleaning kitchen counters, then wringing the sponge clean.science Updated: Jun 17, 2018 07:24 IST
Can the stuffing in your sofa prove an effective tool to combat water pollution? Research conducted by a young Indian-origin scholar at the University of Toronto suggests the simple sponge has the potential to tackle such contaminants.
The inspiration for this field of endeavour for Pavani Cherukupally comes from growing up in Hyderabad and experiencing the degradation of the Musi river that defines that city.
Cherukupally, part of the university’s mechanical engineering department, said, “I have developed a new sponge-based water technology to remediate oil field wastewater using ordinary sponges.
“This water has highly concentrated organic contamination. As you might be aware, Indian rivers such as the Ganga, Yamuna, and Musi also have a high concentration of organic contamination. So, we could extend this technology to remediate Indian rivers.”
The technology of using sponges to soak up contaminants has existed since the 1800s. Most people use them for everyday activities such as cleaning kitchen counters, then wringing the sponge clean.
That is the basis of the simple but effective concept of Cherukupally’s project, which uses newly developed techniques to adapt it to a larger problem. It works as a filter, as she said, “The water passes through it, oil droplets are trapped inside and clean water comes out.”
With a background also in physical chemistry, Cherukupally’s project is aimed, for now, largely at the problem of wasterwater tailings from oilsands in the province of Alberta. Even though 92% of the discharged water is treated, the remainder has added up to over a trillion litres, stored in ponds.
Her concept, now undergoing refining in the laboratory, uses the polyurethane sponge charged to attract the ions of the water’s pollutants that have opposing charges.
“The measurement techniques are new, which allows us to measure the surface charge on the materials and ensure under what conditions exactly this attachment happens and when they will have opposing charges,” she said during the course of an interview.
The system has a removal efficiency of 98%, and it then releases clean water. This particular concept has been developed for offshore filtration but another concept looks at vacuuming the polluted water into the sponge-based system, collecting contaminants and discharging the treated water.
While a lab-scale system is being built for the process, a demonstration is planned for this autumn. She said, “The system configuration to implement at the spill site is finished now.”
Field trials at a facility in Nova Scotia province are expected within a few months. Canadian government agencies such as the department of fisheries and Natural Resource Canada are supporting the research.
Her research is being undertaken under the supervision of mechanical engineering professor Chul Park and Amy Bilton. She is creating a hybrid foam with charged and neutral surface areas under the supervision of chemistry professor Geoffrey Ozin.
Cherukupally believes the technology, once fully developed, can be applied to polluted Indian rivers. Not only will it be effective but it can be used by small industries, since unlike the expensive membranes used at effluent treatment plants, the sponge-based system will be an affordable alternative.
While remove pollutants makes for a healthier environment, she is also actively looking into using the system “to remove water borne bacteria”. As she explained, “As we know, Indian rivers have many microbes in them. Therefore, this direction of the project is also very critical in extending sponge technology to polluted rivers and lakes.”