It’s a busy morning at the dry waste collection center in the Basavanagudi area of Bangalore, India. Two men are loading a dump truck with garbage collected from nearby households.
The air is thick with the smell of decomposition, a smell that occurs only in the presence of wet waste – leftover food, rotting fruits and vegetables, and the like.
So even though the dry waste collection center is supposed to manage only dry waste – such as plastic items, glass bottles, and wood – the center has turned into a temporary dumping ground for mixed waste. It’s temporary because the mixed waste that the men are loading onto the truck will be transported to a landfill about 10 miles away.
But another way of handling waste is also taking hold at this collection center – with TrashBot.
TrashBot is a semi-automatic machine that sorts all kinds of mixed waste into biodegradable and nonbiodegradable components. The technology is believed to be the first of its kind.
Nivedha R.M. and Saurabh Jain developed TrashBot, and they also founded TrashCon, which has been named a top startup in several surveys. The technology is especially useful in India, which has a population of about 1.3 billion and generates some 68 million tons of waste a year.
And TrashBot’s benefits go beyond the amount of waste headed to landfills. “The moment you segregate waste, you can generate value out of it,” says Nivedha, co-founder and CEO of TrashCon.
Many landfills and quarry pits in and around major Indian cities like Delhi and Mumbai have been functioning as virtually the only destinations for waste. This is also true of Bangalore, whose population has grown from about 3 million in the 1990s to as much as 13 million today.
Ideally, waste is sorted into three categories: biodegradable or wet waste, nonbiodegradable or dry waste, and domestic hazardous, which includes sanitary waste. The biowaste would then be composted while recyclable waste would be recovered. But owing to a lack of implementation of waste segregation policies, Bangalore deals with more than 4,000 tons of mixed waste a day.
“In cities, we only segregate about 40% of our mixed waste,” says Swati Sambyal, program manager for environmental governance at the Centre for Science and Environment in Delhi.
The situation is even worse in rural areas. “Large parts of the country are still rural, and bringing in concepts like segregation of waste to such areas is not easy,” says Mr. Jain, co-founder of TrashCon.
Nivedha, for one, was distressed by the disease and pollution that she attributed to mixed waste, and she set about finding a solution. It took a year and a half for her and Mr. Jain to develop TrashBot.
TrashBot has been operating at the Basavanagudi site for about six months. It has segregated some 65,000 pounds of waste, and it has an efficiency rate of up to 99.6%, which is noteworthy since recycling processes need reliability.
“Recyclers ask for specific kinds of material,” Nivedha says. “For example, waste consisting of only nonrecyclable plastics and cardboard can be used to generate RDF [refuse-derived fuel] because such waste would have a high calorific value.” RDF can be used as fuel in cement kilns.
Govind Prasad, supervisor of the ward in Basavanagudi where TrashBot is in operation, has seen positive changes in how waste is handled. “We get a very good share of biodegradable waste, which we convert to manure using our [organic waste converter] machine and use it for all the parks in our ward. And the plastic portion gets recycled,” he says.
TrashBot looks like a rather sophisticated version of a grain crushing machine. When mixed waste is dumped into the mouth of TrashBot, it’s loaded into a magnetic separator where batteries, contaminants, and metals are removed. What remains is carried into a shredder that tears the waste into smaller pieces. During this process, the biodegradable components tend to dislodge from the nonbiodegradable components.
“The main fundamental principle that is most valuable here is that biodegradable waste has about 80% moisture content, whereas the nonbiodegradable component – imagine a plastic cover that is wet – has no more than 40% moisture content,” Nivedha explains. “Understanding this helps create suitable parameters.”
The co-founders have been invited by India’s Department of Biotechnology to help set up policy guidelines. The team envisions situating TrashBots across the country, with each one servicing about 10,000 houses within a radius of about 3 to 4 miles.
TrashBot’s technology “is ideal for areas where segregation is not happening and waste is only being dumped,” says Ms. Sambyal of the Centre for Science and Environment. “But in the long term, a more fundamental shift in mindset is needed.”
Segregation of waste should happen at the household level, she says: “This is the only way we can hope to achieve sustainable waste management practices.”
• For more, visit trashcon.in.