Mahesh Merchant buys plastic bottles and bags from the local garbage dumps in Bangalore for Rs 10 a kg. Meanwhile, in Noida, Rohan Gupta buys old mobile phones for cash—or the chance to plant a tree. Given that there’s enough research to show that plastic, and the plastics in phones (to say nothing of the batteries), are hugely polluting, it looks like Gupta and Merchant are working to clean their cities. What both are doing, however, is running successful businesses from waste.

Merchant’s company, MK Aromatics, extracts 10,000 litres of crude from about 10,000 kg of plastic waste—every day. When refined, 12% becomes high-grade sulphur-free petrol, 40% diesel, and 48% furnace or fuel oil. MK Aromatics has one plant in Bangalore, and a second will be set up in the same city by the end of this year. Revenue, meanwhile, has increased to Rs 5 crore in FY13 from Rs 1.5 crore in FY12. And major corporations, such as Britannia Industries, Unilever India, and Kothari Petrochemicals have agreed to buy furnace oil as part of their corporate social responsibility agenda.

It sounds like the answer to the country’s fuel problems, given the amount of plastic that’s dumped on a daily basis. But Merchant says it’s not easy to run a profitable business. To make economical sense, a plastic-to-petrol plant must be located near the source of the waste—close to the dumps. “But, municipalities won’t sell or lease 5 acres of land near dumps from where 400 tonnes could be sourced daily,” he says.

Gupta, chief operating officer of recycling company Attero, has had better luck buying old phones. “The response has been fantastic. Our collections have been increasing month on month, and in FY12, we collected more than 10,000 phones,” he says. However, he refuses to disclose how much the company has made.

It works like this. Sellers enter the phone details on the company’s website (atterobay.com), and get an initial quote. If they agree to the price, they have to fill a form online, and choose a payment option (cash or voucher). The mobile is then picked up from the seller’s address, and a final quote is given, depending on the age and the condition of the phone.

If the seller accepts the price, the payment is sent within four weeks. If the phones are fit for reuse, their data is wiped out, they are refurbished and resold. If they can’t be reused, they are recycled.

With the increasing use of cellphones, the potential environmental damage resulting from their improper disposal will only increase. The Atterobay method is new for India but has been in use in developed countries for some time now. “The number of companies offering such a service is likely to increase,” says Shyamal Bhattacharya, chief technology officer, PricewaterhouseCoopers, a consultancy firm. More than 221.6 million cellphones were shipped to India in 2012, according to CyberMedia Research, a market research firm.

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