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Thread: Ocean clean up

  1. #1
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    Default Ocean clean up

    Just came across this news today. Very interesting. The first full scale test system transited the gate recently for deployment several hundred miles offshore. I wish them great success. The system is equipped with lights and radar reflectors. I wonder if it has an AIS transmitter? That was not clear from the info and specs. I read.


    https://www.yahoo.com/news/m/ef12b2c...-88%2C000.html

  2. #2
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    Right.

    Lights don't always stay lit. Small boats often don't have radar. How do we keep from running into this thing?

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    Quote Originally Posted by BobJ View Post
    Right.

    Lights don't always stay lit. Small boats often don't have radar. How do we keep from running into this thing?
    Yea, that's what I was concerned about. I certainly don't want to be a party pooper because I totally agree with the mission, but it would be nice to have more info. re navigation warnings on this very large structure. If it does have an AIS transmitter I wonder what it would identify as? I have to believe the USCG did not permit them to plunk this thing offshore drifting around without robust identification systems on board.

    I am going to write them and ask.

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    Their website http://www.theoceancleanup.com says:

    Each system will be equipped with lanterns, radar reflectors, navigational signals, GPS and anti-collision beacons. The AIS will continuously broadcast the location of the systems to passing vessels and the GPS will track the location of our systems, should they veer out of the patch. The US Coast Guard will chart the area as a special operations zone and will issue a Notice to Mariners concerning the presence of our systems.

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    I wrote them about specifics but here is a little more info.

    Will the systems interrupt shipping pathways?
    The ocean garbage patches are vast (three times the size of France) and vessels crossing through it are rare - on average there are less than five within its boundaries. Coupled with the relatively small size of the cleanup systems, the chances of a vessel interacting with a system are minor.

    But minor does not mean impossible. Hence it is crucial that we fit our cleanup systems with safety equipment, as is required for any other oceangoing vessel.

    To prevent collisions, we defined five ‘safety rings’ around the system through which we aim to do everything possible to notify vessels of our systems’ whereabouts. Navigational warnings will be broadcast through the Notice to Mariners with current system location information. Additionally, the systems are fitted with many detection capabilities so that vessels can avoid our systems. For instance, our first cleanup system is fitted with nine light masts that rise four meters above the waterline, AIS beacons and radar reflectors.

    We will also continuously monitor the health and whereabouts of our systems 24/7 through on-board cameras and GPS trackers. We will be able to identify when the system drifts too close to the edge of the patch (where the vessel traffic density is higher), after which we can engage in a manual correction of the system’s trajectory, towing it back to the center of the patch.
    Last edited by mike cunningham; 09-12-2018 at 05:17 PM.

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    Sounds pretty good.

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    pogen is offline Sailing canoe "Kūʻaupaʻa"
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    Well no one likes plastic in the ocean, but I'm a bit skeptical. They also don't go into too much detail on how they don't kill smaller fish, krill, jellys etc.

    Note a 500 m aperture sweeping at 2 kts (1 m/s) over an area of (1000 km)^2 would take 63 years. Maybe they only sweep 1 kt, and only do 200m. But a few hundred of them might do some good. Then you have to actually get all the plastic back to shore and into a landfill. Or compress it at sea to solid masses heavier than water, that will not ever themselves disintegrate, and sink them?

    Meanwhile the the pollution is still incoming, mostly from 10 rivers in Africa and Asia.

    https://www.scientificamerican.com/a...in-the-oceans/

    https://phys.org/news/2017-06-plasti...rce-ocean.html

    So if there is no source control, this whole program is basically a bunch of Americans spending money to move plastic refuse from China to landfills in the western US.

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    Quote Originally Posted by pogen View Post
    Well no one likes plastic in the ocean, but I'm a bit skeptical. They also don't go into too much detail on how they don't kill smaller fish, krill, jellys etc.

    Note a 500 m aperture sweeping at 2 kts (1 m/s) over an area of (1000 km)^2 would take 63 years. Maybe they only sweep 1 kt, and only do 200m. But a few hundred of them might do some good. Then you have to actually get all the plastic back to shore and into a landfill. Or compress it at sea to solid masses heavier than water, that will not ever themselves disintegrate, and sink them?

    Meanwhile the the pollution is still incoming, mostly from 10 rivers in Africa and Asia.

    https://www.scientificamerican.com/a...in-the-oceans/

    https://phys.org/news/2017-06-plasti...rce-ocean.html

    So if there is no source control, this whole program is basically a bunch of Americans spending money to move plastic refuse from China to landfills in the western US.
    There is an interesting presentation by Ocean Cleanup's charismatic founder (Boyan Slat) at

    https://www.youtube.com/watch?v=du5d5PUrH0I&t=1585s

    And some additional technical information described at

    https://www.youtube.com/watch?v=NkC0h1CcHJs

    Slat comes across as being realistic in his projections and about the challenges the technology faces. He acknowledges the job can not be completed without focus on elimination the many sources of the problem.

    I don't want to come across as a fanboy, the challenges are huge, no question, but with regard to disposition of collected plastic, the intent is to unload the collectors by means of shore based transport and recycling of the collected material with some (probably not enough) income being derived. Slat asserts an environmental cost benefit analysis on this strategy has been completed and shows the benefits far outweigh the carbon footprint of the transport. With regard to sea life, Ocean Cleanup asserts the skirts (solid fabric not net) extending about 10 feet below the pontoon create a slight downward current as the device moves through the water and basically pushes neutrally buoyant sea life below the skirt as the device passes. I assume the buoyancy of the plastic debris resists this slight downward flow.

    With regard to the collection vs surface area math. According to the presentation, Ocean Cleanup's studies have revealed plastic is not evenly distributed in the patch. It is concentrated in eddies, etc. within the dominant current. Conveniently, the collection devices tend to align themselves with these same eddies and are therefore located at the points of greatest debris concentrations. In theory the collection can continue ad infinitum or until we can get a handle on the sources of the material which is likely to take a very long time - unfortunately. In the meantime, the ocean is significantly cleaner and the very damaging small particle generation problem is mitigated substantially.

    So that's the founders's pitch. I think you are correct to be skeptical, but our mutual experiences at sea really highlight the fact there is a big big problem. If an outfit has a shot at doing something about it I think more power to them. No risk, no reward.

    There appears to be some smart money involved to the tune of $25 - 30 million. Probably more a philanthropic gesture than an expectation of riches but they think enough of the technology to fund a moonshot.

    With regard to your last paragraph, I am full agreement on that point with exception of recycling vs landfill.
    Last edited by mike cunningham; 09-13-2018 at 11:08 AM.

  9. #9
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    I think it is wonderful to see this young man's idea coming together.
    Sure, it is a test phase, but moving forward.

    Yes, the real solution starts at home. Reusing, recycling, and helping pick up after the um, less enlightened.

    Even if you can only do a little, it is of the utmost importance that you do it. (Not sure where that one came from)

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