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How to tow an iceberg

  1. Aug 12, 2011 #1
    First of all, mods/Berkman, I apologize if this is once again in an improper place on the forum, I would have gone with engineering were it not such a harebrained idea, so, here goes nothing..

    First, exceprts, from article from a few days ago, Physorg, 8/09/2011

    " Simulation shows it’s possible to tow an iceberg to drought areas "

    Way back in the 70’s Georges Mougin, then an engineering graduate, had a big idea. He suggested that icebergs floating around in the North Atlantic could be tethered and dragged south to places that were experiencing a severe drought, such as the Sahel of West Africa. Mougin received some backing funds from a Saudi prince but most “experts” at the time scoffed at his idea and the whole scheme was eventually shelved.

    Cut to 2009 and French software firm Dassault Systemes, who thought maybe Mougin was on to something after all and contacted him to suggest modeling the whole idea on a computer. After applying 15 engineers to the problem, the team concluded that towing an iceberg from the waters around Newfoundland to the Canary Islands off the northwest coast of Africa, could be done, and would take under five months, though it would cost nearly ten million dollars.

    In the simulation, as in a real world attempt, the selected iceberg would first be fitted with an insulating skirt to stave off melting; it would then be connected to a tugboat (and a kite sail) that would travel at about one knot (assuming assistance from ocean currents). In the simulated test, the iceberg arrived intact having lost only 38 percent of its seven ton mass.

    The rest of the article at the link:

    http://www.physorg.com/news/2011-08-simulation-iceberg-drought-areas.html

    So what I am wondering/thinking, is if they project losing 38% of the mass by towing at the surface,..why not sink them and tow them ?

    Go down ~ 1k' ( Thermocline ) and the temps range from 37f and go down to 32f after a few thousand feet.

    1/4 cup of h20, frozen, weighs ~29.575gms (rounded up) to 30gms , I found it takes ~ 2.5gms to counteract buoyancy, an extra 12% on top of the original weight of the ice.

    Usually only around 1/9 of an iceberg is above surface.

    My idea is based on solution mining and waterflooding ( two gas and petroleum industry practices ), the type they use to excavate chambers in underground salt deposits for storage of petroleum products/chemicals. Basically, they use high pressure water to dissolve the salt and create a cavity.

    http://solutionmining.org/assets/files/BriefHistory.pdf [Broken]

    Waterflooding is a process, again basically, where they pump high pressure engineered fluids into low producing petroleum deposits, there are many types with many results, the one I am going to make reference to is a waterflood with deoxygenated/degassed brine, usually chlorinated to kill off h2s producing microbes that turn wells "sour".

    Since solution mining is possible, why couldn't a cavity be mined out of a berg ?

    Since degassed brine is very dense, and it only takes roughly 12% of the original weight of a given mass of ice to counteract buoyancy,ie sink the ice, a cavity containing brine would provide the extra 12% needed.

    With that put aside for a minute, I also thought about how methane can lower the density of water, in essence allowing a buoyant object to sink, I have read accounts of hydrate/clathrate deposits being hit by drilling rigs, starting a cascading phase change and allowing the hydrates to dissociate, lowering the water and the rigs have either sunk or listed heavily.

    Hydrates can easily be dissociated with ultrasound( something I proposed to BP last year )

    So, why not use extra weight inside a berg, in the form of degassed brine, manufactured onsite, pumped into a cavity created by solution mining and plugged with more ice, at the same time dissociate hydrates ( or release methane from tanks under the berg ) to sink it
    1-2 thousand feet to the low temperature zones ?

    The internal temp of many bergs ranges from 10f to -5f, so were it sunk to a depth where the temperatures are roughly 37f and below, it would slow melt rates substanially, also pressure at that depth would help keep the berg below the surface, I think.

    Maybe even imbedd a methane release system at the bottom of the berg to be able to control the buoyancy ?

    In the event brine wouldn't work, why not lead/concrete/locally obtained Earth fill, etc ?

    They could be sunk, manuvered into deep-sea currents and towed around the world.

    ...ok, that's my fruitcake idea, I know there are many variables I didn't touch on, so go ahead, crush my dreams.


    :cry:
     
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Aug 12, 2011 #2
    That sounds a lot more expensive than just accepting a 32% loss of mass. It might be more economic to somehow shape the leading face of the berg into a more ?hydrodynamic? shape to improve towing speed and decrease resistance.
     
  4. Aug 12, 2011 #3

    FlexGunship

    User Avatar
    Gold Member

    Someone beat you to the punch!

    iceberg_ship.jpg
    (Source: http://www.thebestpageintheuniverse.net/c.cgi?u=af07_more_truth)
     
  5. Aug 12, 2011 #4
    Lol, funny photo, reminds me of the sawdust and ice ships the US Navy was toying around with at the end of ww2.

    If you sank a berg and turned it sideways the leading edge would be more hydrodynamically effecient though, wouldn't it ?

    It does sound expensive ....but then again, desal plants are not cheap either, some designs, like Japanese nuclear-powered desal plants sound like a bad idea for ex, in light of recent events.

    Brine is found in great quantity in areas like Greenland, Norwegian, and Labrador Seas in the Northern Hemisphere, and close to the Antarctic continent in the Weddell and Ross Seas in the south, salt basically ends up being exuded from freezing water( I know that's probably incorrectly described ) but point is, it's found onsite, no need to make it, it'd likely be the correct density too.

    " Scientists uncover deep ocean current near Antarctica, article from April 27/2010

    http://www.discoveryon.info/2010/04/scientists-uncover-deep-ocean-current.html

    " Rintoul, of the Antarctic Climate and Ecosystems Cooperative Research Center in Hobart, said it proved to be the fastest deep ocean current yet found, with an average speed of 20 cm (7.9 inches) a second. It was also found to carry more than 12 million cubic meters a second of very cold, salty water from Antarctica. "

    So with deep currents like that, it still wouldn't be economically feasible ?

    Thanks for humoring me guys. :tongue2:
     
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