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Giant Plastic Trap Breaks, Gets Towed Back To Land (npr.org)
The "Ocean Cleanup" project deployed a 2,000-foot floating debris trap in September near a drifting plastic patch in the Pacific Ocean that's twice as big as Texas. It broke.
An anonymous reader quotes NPR: Invented by Boyan Slat when he was just 17, the barrier has so far done some of what it was designed to accomplish. It travels with wind and wave propulsion, like a U-shaped Pac-Man hungry for plastic. It orients itself in the wind and it catches and concentrates plastic, sort of. But as Slat, now 24, recently discovered with the beta tester for his design, plastic occasionally drifts out of its U-shaped funnel. The other issue with the beta tester, called System 001, is that last week, a 60-feet-long end section broke off.
The first issue, Slat said, was likely due to the device's speed. In a September interview with NPR, he said the device averages about four inches per second, which his team has now concluded is too slow. The break in the barrier was due to an issue with the material used to build it. "In principle, I think we are relatively close to getting it working," Slat said in an interview Saturday with NPR's Michel Martin. "It's just that sometimes the plastic is also escaping again. Likely what we have to do is we have to speed up the system so that it constantly moves faster than the plastic." For the material failure, Slat said his team will probably try to locally reinforce the system to combat the problem of material fatigue.
Slat's U-shaped plastic trap is now being towed the 800 miles back to Hawaii for repairs.
An anonymous reader quotes NPR: Invented by Boyan Slat when he was just 17, the barrier has so far done some of what it was designed to accomplish. It travels with wind and wave propulsion, like a U-shaped Pac-Man hungry for plastic. It orients itself in the wind and it catches and concentrates plastic, sort of. But as Slat, now 24, recently discovered with the beta tester for his design, plastic occasionally drifts out of its U-shaped funnel. The other issue with the beta tester, called System 001, is that last week, a 60-feet-long end section broke off.
The first issue, Slat said, was likely due to the device's speed. In a September interview with NPR, he said the device averages about four inches per second, which his team has now concluded is too slow. The break in the barrier was due to an issue with the material used to build it. "In principle, I think we are relatively close to getting it working," Slat said in an interview Saturday with NPR's Michel Martin. "It's just that sometimes the plastic is also escaping again. Likely what we have to do is we have to speed up the system so that it constantly moves faster than the plastic." For the material failure, Slat said his team will probably try to locally reinforce the system to combat the problem of material fatigue.
Slat's U-shaped plastic trap is now being towed the 800 miles back to Hawaii for repairs.
I, and probably you too, came up with much greater things when we were young.
And we could also have actually created them.
But I don't remember us having millions to pay engineers and entire damn towing ships and so on.
I literally (not making this up) had toilet rolls, marbles and dirt to play with.[1]
So ... where do I apply for that opportunity mother lode?
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[1] That’s what my parents could offer us. To make up for it, we stole stuff from construction sites, and used things from the forest, to build tree houses. Which was a lot of fun. But would I have had a ruby and a neon tube, I would probably have been able to build a laser before puberty (in the 80s, mind you). I knew exactly how.
Almost all the plastic trash going into the sea is coming from a handful of rivers in Asia & Africa. So why not put this plastic trap at the river mouths of those high trash rivers, like the Ganges or Yangtze? Seems to me like it would be easier to catch the plastic in such concentrated locations, before UV rays & ocean waves have broken it down into little bits.
Clearly you have never burned plastics before. Its a nasty process that releases lots of weird toxic fumes.
Depends on the temperature, pressure, and atmosphere you burn it under. A simple higher temperature, like found in an incinerator, will turn common plastic (polythene, polypropene, styrene, butadiene, acrylonitrile, ) into H2O, CO2, and N2.
In practice you get some NOx rather than N2 from acrylonitrile. And some chlorine compounds if there is any polyvinyl chloride in the mix. You can deal with both with some chemistry in the scrubbers. Some waste compounds like formaldehyde are valuable for making more plastic.
Then there's the fact that it takes LOTs of energy to burn plastics, probably more than to melt a metal with a low melting point like Aluminum.
You say it's a "fact", but it's not true. There commercial systems currently in operation that burn plastic for net energy. Holding a match under a chunk of plastic isn't the same as blowing with a gas mix in a high temperature oven.
Gasification in "waste-to-energy" plants is what gets the media excited, because it can go into modified cars. But I don't agree that it is worth the additional energy and processing. On site power generation is simpler than a gasification plant and avoids the waste in conversion, bottling and shipping.
“Common sense is not so common.” — Voltaire