This won't work.
1) The north pacific is not a very forgiving place. The forces of the seas on a 2000' tube will break it and its parts - quickly.
2) The idea that you could anchor a barrier in the open ocean currents is absurd. The ocean current is like a river, only your movement relative to the water surrounding you is relevant, without the influence of the wind you move with the current. Its like going down a river in a float tube, putting your feet down and expecting t0 magically start to move upriver. The average depth of open ocean currents is 200 meters. In order to get any sort of 'anchor' or 'drag' effect out of that your 'anchor' would have to be at least 200m deep AND be larger than whatever was on the surface layer.
3) How would you collect the plastic from the 'barrier'? You would obviously have to have some kind of support vessel harvesting the plastic. Words cannot express how dangerous it is to handle something loose in the water like a 2000' tube. Not to mention expensive! It costs about $30,000/day to charter a support vessel to handle this task.
4) Say you have a 2000' tube collecting garbage. The density of the GPGP at its greatest is only 1g/m2. https://www.fastcompany.com/40548220/the-great-pacific-garbage-patch-is-16-times-bigger-than-we-thought. If your 610m tube has 1km/hr of current pass through it and a generous 100% collection rate you would 'harvest' 610 kg of trash an hour, this would take approx 131 thousand hours to collect the estimated 80 metric tons of trash in the GPGP, or approximately 15 years. Also, the GPGP is big. Really big. No, bigger than that. About 1,000,000 sq miles big.
5) Obviously the ideal method would be to use an 300' square offshore mobile platform with DP-3, 4 azipodal thrusters, have solar panels cover the top of the platform except for a corner heli pad along with additional extendable solar panel 'wings' on all four sides. The decks below would house processing facilities, accommodations and power/mechanical facilities. Underneath the platform would be some kind of plastic collection device. The plastic would be collected, processed on the platform with at least one by-product being diesel fuel, and use solar power with diesel backup to keep itself on station processing waste, with the diesel fuel and other products (such as cubes of recycled plastic) capable of being transferred at sea to lightering vessels which would transport it ashore.
6) #5 above would cost about $200m to build, but would probably struggle to collect enough plastic to make a profit. Because there really isn't that much plastic out there in the ocean and most of it has sunk already. (1g/m2 max on surface). But what do I know. I only work out here.
7) None of you are going to read #5 and #6 and I will get downvoted for 'not offering a solution'.
Also, 98% of ocean plastics aren't pieces of litter that just float on the surface waiting to be scooped up. The vast majority are tiny microplastics (smaller than a grain of rice) evenly distributed in the water column. This machine, if it doesn't immediately get smashed, would only pick up things larger than 2 cm that happen to be on or near the surface.
This is one of those feel-good headlines that everyone loves, but ocean scientists have been extremely skeptical about this project because it's completely divorced from reality.
Since young inventor Boyan Slat first began, at about age 18, to get attention for his idea, marine biologists and oceanographers have been fairly pulling their hair out at the Ocean Cleanup's huge social media popularity. It makes sense that Slat's idea has become popular. Vague but persuasive sales pitches that promise to solve problems without us having to change our behavior? They're always popular. But here's what's got those scientists in a cranky mood: Slat's idea almost certainly won't make enough of a dent in the ocean plastic pollution to be worth the effort, it will almost certainly injure wildlife already struggling from an ocean with too much of our stuff in it, and the rigs may end up becoming more shredded pieces of plastic in an ocean already literally awash in plastic.
98% of plastic in the ocean are microplastics smaller than a grain of rice, evenly distributed throughout the water column. This machine, if it doesn't get smashed to bits, would only collect things lager than 2 centimeters that happen to be on or near the surface. Things like fish and wildlife. The feasibility study for this project even admits that "Highly migratory species will be highly affected by this project. Swordfish, marlin, sailfish, sharks, tuna-like species are all highly susceptible to being caught in the holding tanks, and possibility diverted by the booms into the platform."
If I had a dime for each brilliant idea to “clean up the “Garbage Patch” that has been forwarded to me over the last few years I would be a millionaire. These gyre cleanup machines, devices and foundations that emerge periodically are not going to happen. However they are likely to get lots of media attention –and distract from the real solutions.
First, there is a gross misconception about what garbage patches are. Plastics take hundreds of years to biodegrade, buy they fragment rather quickly into smaller and smaller particles. Science shows that the vast majority of plastics in the ocean are tiny, under 10 mm in size. The concentrations are very thin, and the particles are scattered throughout the water column of all oceans in the world. In actuality what we have is a planetary soup of plastic particles. In some areas concentrations are higher. These are the “garbage patches", located in the ocean gyres sometimes as vast as continents, where the soup has higher and more consistent concentrations of particles. That’s all. In order for these machines (assuming these get paid for, built and deployed) to capture significant amounts of plastic, they would need to cover millions of square miles of ocean and somehow manage to tell plastic particles apart from other things of the same size, such as fish eggs and plankton, which are essential to all marine life.
Also, the people who come up with some cleanup machines, ranging from product designers to teen-prodigy inventors, often seem to forget a not-so-minor detail: that the ocean is not still, and flat like a giant blue tennis court. The ocean is always moving, sometimes with amazing force. In the unlike event of these contraptions ever being made, they would be pushed around all the time –when not torn to pieces and sunk.
Another key detail that seems to be consistently forgotten is that millions of tons of new plastic trash are entering the ocean as we speak. A fairly old and conservative study estimated that 6.4 million tons of plastic waste enter the ocean every year –adding up to over 100 million tons of plastic already polluting our oceans. Trying to clean this spiraling mess with ships or machines would be like trying to bail out a bathtub with a tea spoon… while the faucet is running!
What about stopping plastic pollution at the source? Wouldn’t that be a better use of our ingenuity, time and money? It also happens to be quite doable too. The plastic industry loves distractions like the cleaning machines, because they put the focus on “cleaning up”, not on how their business of making disposable plastics is destroying the planet. It is also interesting to notice how strongly our culture equates “solution” with “process” and/or “machine”. One immediately has to ask: “What would be the solution for these solutions?” But even given all the misconceptions and cultural trappings that surround us, one has to wonder how these whacky ideas get so much media traction. Different variations of the theme come up often, along with their cousins: the miracle machine that turns plastic into oil, and the 16 year old that discovers a plastic eating bacteria in his garage.
Ultimately, in addition to the relentless activity of vested interest that promote these misconceptions, these stories get passed around because we all like to hear a whisper in our ear that says “it’s all going to be OK. Keep consuming and don’t think too much.”