As the world gets ready to focus on reducing carbon dioxide emissions and cleaning up the environment at the COP 26 meet in Glasgow next month, a small effort in India is ready to upscale and contribute its bit to getting rid of plastic waste from our rivers.

Geocycle India, the in-house waste management arm of Ambuja Cements and ACC, has been testing the waters (literally) in a project that addresses marine plastic pollution and co-processes non-recyclable plastic in cement production.

In a pilot project this year in April, Geocycle supported the plastic-free Agra mission through the ‘bubble barrier’ technology used to clean up oil spills in oceans. In 2019 it was tested for clearing plastic waste from rivers. Under the United Nations Environment Programme India’s ‘Air Pollution Control Action Plan’, Geocycle partnered with Agra Municipal Corporation and GIZ India, along with Canadian Pond as technology provider.

Geocycle commissioned the pilot on the Mantola canal, which carries 40 per cent of Agra’s wastewater, and successfully prevented 500 tonnes of waste from entering the Yamuna river. “Agra was chosen, as the historic city is a tourism hotspot and plastic pollution is a serious challenge here,” explained Neeraj Akhoury, CEO India, Holcim Group, and MD and CEO, Ambuja Cement Ltd.

The ‘bubble barrier’ now collects nearly 2,400 tonnes of plastic from the canal every year. A similar one will be installed at Varanasi, on the Varuna river, right before its confluence with the Ganga, says Akhoury. Yet another is likely to come up at a large urban centre in Gujarat, he adds.

The ‘bubble barrier’ involves placing perforated air tubes under the surface of the waterbody, across its breadth; they can be placed at a depth or even on the floor of the waterbody, depending on the water quality. The tubes are connected to a source of compressed air, which is powered by renewable energy. This air forms a vertical sheet of bubbles, or ‘bubble barrier’, which forces plastic to the surface of the waterbody. Since the tubes are arranged diagonally across the canal, the afloat plastic waste is pushed by the current to the riverbank, where it is collected and sorted. Non-recyclable plastics are sent to the cement manufacturing units.

The target is ambitious — collecting 5,000 tonnes of plastic waste within two years. The Geocycle bubble barrier can be installed on lakes and artificial waterbodies as well. The modular design can be scaled up easily,” says Akhoury.