CHENNAI: The Tamil Nadu State Planning Commission has recommended the state government to adopt Black Soldier Fly (BSF) bioconversion technology for solid waste management on a pilot basis in five cities, particularly Chennai.
In its report titled ‘Organic Waste Management in Urban Tamil Nadu’, released on Tuesday, the commission noted that Chennai, which generates 5,000 tonnes of waste per day, accounted for more than one-third of the total 14,600 tonnes produced daily across Tamil Nadu.
However, despite ongoing efforts towards biomining and scientific closure of two existing landfills in Kodungaiyur and Perungudi, the progress remains slow, while the city keeps generating more waste that ends up in landfills. This challenge could be addressed by adopting BSF bioconversion technology, it said.
BSF is a non-pest, non-vector insect species. Unlike common houseflies, BSF do not transmit diseases, bite, or sting, and are not attracted to human habitation.
BSF uses the feeding capacity of its larvae to rapidly convert organic waste into valuable products such as protein meal, insect oil, and frass fertiliser. The larvae can consume up to four times their body weight in waste daily and reduce waste mass by 50–80%, while producing near-zero methane emissions as the process involves an aerobic mechanism.
Moreover, with the city corporation planning for more windrow composting centres, the report said, BSF larvae processes organic waste within 12 to 15 days — compared to 35 to 49 days for windrow composting — at a fraction of the land requirement.
The report highlighted that, in March 2023, a massive fire at the Brahmapuram waste management site in Kochi continued for 12 days on nearly 60 acres, releasing toxic fumes and forcing the closure of schools and colleges.
Following this, Kochi undertook large-scale biomining and introduced BSF technology to process municipal wet waste, becoming the first Indian city to deploy it at a municipal scale with success. The technology is also adopted in Bengaluru and Mangaluru.
The commission urged the state government to allocate funds to launch the BSF technology on a pilot basis in Chennai, and also in Coimbatore, Madurai, Tiruchy, and Salem, before scaling up across Tamil Nadu.
The report said that waste segregation in Chennai is poor compared to cities like Indore (100%) and Lucknow (97%). This is despite Chennai adopting a comprehensive PPP-based waste management and decentralised processing through micro-composting centres and resource recovery centres, it said. In reality, several MCCs and RRCs have, however, been closed.