New Machine Aims to Combat Toxic Algae Blooms
University of Bath experts are testing a novel cavitation-based device to break down harmful cyanobacteria in lakes.
Researchers from the University of Bath are developing and testing a new machine designed to tackle the proliferation of toxic blue-green algae, also known as cyanobacteria, which can pose risks to human and animal health. The device, which utilizes a process called cavitation, is currently undergoing trials at a lake in Warminster, Wiltshire.
The algae blooms have become a recurring problem in Warminster's Pleasure Grounds, particularly during warmer months. Kevin Whitehorn, estates manager for Warminster Town Council, noted that this year's bloom has been worse than in previous years, exacerbated by lower water levels. The persistent algae have led to the closure of the lake for recreational activities for several months, impacting the local model boat club and public access.
Dr. Sanjay Nagarajan, a chemical engineer from the University of Bath's Institute for Sustainability and Climate Change, was inspired to investigate a solution after seeing the lake closed to the public. Working with colleagues, including Dr. Madhubalaji Chegu Krishnamurthi, who has studied algae for a decade, Nagarajan developed a machine incorporating a reactor that uses cavitation to break down the cyanobacteria.
The cavitation process, as explained by Nagarajan, involves manipulating conditions within the reactor to create tiny bubbles. When these bubbles implode, they generate powerful localized effects that can destroy algal cells and degrade toxins. "We've seen up to 20% degradation in terms of toxins and we've also seen a lot of the algal cells being destroyed because of the effect of cavitation," Nagarajan stated.
While the type of reactor is not novel, its specific application for algae destruction is. The current prototype, built using improvised equipment that includes a generator and components typically used for home brewing, has shown promising early results. The team aims to secure funding to scale up the technology into a larger machine that could be loaned to local councils to manage algae blooms in their water bodies.