Celebrating women achievers: a professor hooked on plastic recycling

Punch the plastic metal hook. Photo: Special Arrangement 
| Photo Credit: SPECIAL ARRANGEMENT

Indumathi M. Nambi does not want to let plastic waste off the hook. Never a believer in half measures, she brings a real hook to her campaign — a hook designed by her students under her guidance.

A professor with the environment and water resources division of the department of civil engineering at IIT-Madras, Indumathi shapes opinions about environment issues not just inside the classroom but outside as well. And given her influence in sustainability circles, this hook — one designed to punch the plastic — found a ready taker in Residents of Kasturbanagar Association (ROKA). ROKA adopted it when it launched its “We Segregate” project with the support of Okapi Research and Advisory in October 2023.

Punch the plastic contraptions are available in the market, but ROKA wanted to go in for something locally devised to make complete the picture of sustainability. IIT-M had devised the hook at its work station; and around World Sustainability Day (October 26) in 2022, it unveiled the hook as part of its Punch The Plastic drive.

Here is how it works: used milk packets, snack wrappers and other flimsy plastics that are usually carelessly disposed of, sometimes even allowed to fly about would now be nailed and kept in waiting till enough is accumulated for the recycler to arrive and whisk the bunch of plastics away, thanks to the sturdy metal hook.

“The need for a hook instead of a bin is to collect clean and dry plastics which can be used directly for recycling,” Indumathi explains. “It is not about forcing people to recycle. It is about making the process so effortless that not doing it feels ridiculous.”

There are two strands to ROKA’s We Segregate project — one has to do with three lane composters stationed on the streets of Kasturba Nagar for residents to deposit organic waste in; and the other has to do with the hooks sunk into walls of apartments and houses.

Indumathi and her students at IIT Madras are working on expanding the initiative to more residential areas. Given its low cost and ease of use, the model can be adopted anywhere with the least amount of fuss.

“The reality is, plastic use is not going away anytime soon,” she says. “But if we stop treating it as garbage and start treating it as a resource, the way we manage it will change entirely.”

The metal hook marks only a minor milestone in Indumathi and her student-team’s journey toward addressing the plastic pandemic.

Here is a glimpse into an ambitious project. 

At IIT Madras, they developed a pyrolysis plant, using which multi-material multi-layered plastic packaging (MMPP), aluminum-laminated wrappers and composite materials amongst others that previously had no recycling pathway are now broken down into oil with properties similar to diesel. In addition to the one in IIT-M, the team has parked a demo plant at Perungudi.