A pioneering Dutch experiment to try collecting plastic rubbish from the oceans has successfully caught floating debris for the first time.
Boyan Slat, founder of The Ocean Cleanup, said that after a failed effort last year, his giant v-shaped boom system had overcome technical challenges to start removing waste.
“We are now catching plastics,” he told journalists yesterday. “We now have a self-contained system in the Great Pacific Garbage Patch that is using the natural forces of the ocean to passively catch and concentrate plastics.”
The proof of concept comes three years after Slat tested a prototype in the North Sea in a bid to offer a solution to tackling the hundreds of thousands of floating tonnes of plastic being carried by gyres in the mid-Pacific. Arjen Tjallema of The Ocean Cleanup told New Scientist that the feat had proved the sceptics wrong. “This shows our technology is actually capable of collecting plastics. This is a big milestone – there is a feasible solution to the problem.”
An attempt by the group failed last year, after the boom failed to keep a consistent speed on the ocean’s surface, allowing plastic to drift free. A part of the system also broke off, forcing a return to port. A redesigned system was launched in June, and has an underwater parachute to create drag and slow it down.
However, while plastic debris was channelled into the boom after this improvement, it escaped by overflowing the yellow buoys that make up the system. Tjallema says the answer was relatively simple – the group simply stuck three of the buoys on top of one another, taking the boom’s height to about half a metre above the waves. Waste has been collected in the past month.
The group doesn’t say what quantity of debris it collected, but Tjallema says the amount is largely irrelevant because the test was about proving the technology, which now needs scaling up. Slat says the system caught all sizes of plastic, from microplastics to ghost nets for fishing, as well as other rubbish. “Anyone missing a wheel?” he joked on Twitter.
Rebecca Helm at the University of North Carolina warned that animals had been captured by the system, including by-the-wind-sailors and blue-buttons, relatives of jellyfish that are part of the diet for birds, fish and turtles. “Part of my alarm is that we know so little about these animals and this ecosystem that we have no way of evaluating impact. Plastics may harm them, but collecting and removing them from the ocean’s surface along with plastic will absolutely kill them. Neither is good,” she says. The Ocean Cleanup group says it is not happy it had captured the organisms but it expected the impact to be minimal.
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