New Delhi, the capital of India, chokes every winter as cool air traps a toxic blend of pollutants from crop burning, car exhausts, open fires, construction dust and industrial emissions close to the ground.

The annual scourge has been particularly bad this season, and short-term measures – such as shutting factories and restricting car use – have failed to have a significant impact.

In November, doctors declared a public health emergency and schools were shut across the capital.

Fumes from diesel backup generators are a central ingredient in the noxious cocktail, but one company is turning this bad air into ink and paint with technology that can capture up to 90% of dangerous pollutants.

Chakr Innovations, started by graduates from the Indian Institute of Technology, has capitalised on the smoke-belching machines that can be heard across the city.

Its Chakr Shield is fitted to generators and converts carbon and other fine particles, including the most harmful PM0.3 and PM2.5 specks, into liquified soot through chemical and heat-exchanging processes.

Arpit Dhupar with a device that can capture 90% of black particles from diesel generators.

(PM2.5 refers to the size of 2.5 micrometers, or about 30 times smaller than human hair. Since the particles are so small and light, they hover longer in the air. They also penetrate deep into the lungs and even our bloodstream. They are said to trigger or worsen asthma, heart attack, bronchitis and other respiratory problems.)

The captured carbon is washed down with a solvent and processed into ink pigment and paints.

“What would have otherwise been a waste (polluting the air) is captured and reborn to be used as a raw material again,” said co-founder Arpit Dhupar, donning a t-shirt that says “black is the new green”.

Dhupar was inspired by seeing a diesel generator that was running a roadside sugarcane juice stall and turning the wall behind it black in the process.

Chakr has fitted machines at more than 18 Delhi offices, and 30 other companies have signed up for the technology, including US giant Dell Computers, which will be using Chakr’s ink for printing on its cardboard boxes.

Dhupar said that in 18 months, the machines had collected enough carbon to pollute about 1.5 billion litres of air.

“We are running out of clean, breathable air in Delhi and our definitive objective is to make the access to clean air a basic right for everyone,” he said. – AFP

See how one company “washes” the polluted city air until it’s as fresh as the mountains.