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Hierarchical Membrane For Cleaning Up Oil Spills

Posted by Unknown on from the what-about-anarchist-membranes dept.

rtoz (2530056) writes Whenever there is a major spill of oil into water, the two tend to mix into a suspension of tiny droplets, called an "emulsion." It is extremely hard to separate them, and they can cause severe damage to ecosystems. Now, MIT researchers have discovered a new, inexpensive way of getting the two fluids apart again. This new approach uses membranes with hierarchical pore structures. The membranes combine a very thin layer of nanopores with a thicker layer of micropores to limit the passage of unwanted material while providing strength sufficient to withstand high pressure and throughput.

22 of 32 comments (clear)

  1. Solved problem by snsh · · Score: 5, Insightful

    Easier to follow Exxon's example and dump tons of dispersant into your oil spill, and watch the globs disappear from plain sight.

    1. Re:Solved problem by pepty · · Score: 5, Funny

      You know, I don't think I've ever heard of a mix of cash, lawyers, and lobbyists being referred to as "dispersant" before.

    2. Re:Solved problem by frinkster · · Score: 3, Insightful

      Easier to follow Exxon's example and dump tons of dispersant into your oil spill, and watch the globs disappear from plain sight.

      How this got moderated as Interesting I have no idea - I found it to be quite funny.

      But the truth is that that industrial corporations are very sensitive to economics. Crude oil is very valuable and dispersant is very expensive. Any product that allows them to recover the oil economically will be used extensively.

      The environmental movement really advanced when people started explaining to corporations that pollution was nothing more than raw inputs that they paid for and are now throwing away. A lot of industrial companies have entire divisions dedicated to selling products produced with what used to be stuff they threw out or paid someone to dispose of.

    3. Re:Solved problem by internerdj · · Score: 1

      However it seems a technically accurate term.

    4. Re:Solved problem by i+kan+reed · · Score: 3, Informative

      BP got in big trouble for an internal memo that discussed the idea of reclaiming the oil. It was a "how dare they think of protecting their assets after doing this" outrage.

      I don't have a strong opinion about that memo or the outrage(even though I'm quite concerned with environmental matters on principle). Just that that happened.

    5. Re:Solved problem by Immerman · · Score: 2

      Perhaps. Economically is the key word though, and that filter is going to have to be phenomenally cheap and effective to make it worth it for recovering oil from seawater. How many barrels of oil at $100 per barrel do you suppose $100 worth of filter can filter out? And then you have the fact that the filtered oil is going to be thoroughly contaminated with salts, plankton, diatoms, and everything else found in seawater that's either oil soluble or bigger than an oil molecule, which could potentially increase refining costs considerably. Plus the costs of operating all the ships and pumping equipment necessary to chase an oil slick around the ocean and filter all that seawater in the first place, which is probably going to dwarf the cost of filters.

      This could be a great thing for spill cleanup, It might even help to substantially defray the costs of performing it. But I suspect oil companies will still have to be legally forced to clean up after themselves - after all, they generally don't own the oil until after they've pumped it, and pumping more oil is going to be far more profitable than filtering a spill.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    6. Re:Solved problem by LifesABeach · · Score: 1

      I'd watch it on Pay Per View.

  2. Is this better for pour-over or French Press? by pepty · · Score: 4, Interesting

    Solomon performed experiments showing the effectiveness of the membranes in separating nanoemulsions while maintaining integrity at high pressure. The team used various techniques — including differential scanning calorimetry, dynamic light scattering, and microscopy — to test the separation efficiency, showing more than 99.9 percent separation. Microscopy images show the membrane in operation, with dye added to the water to make the droplets more obvious. Within seconds, an oil-water mixture that is heavily clouded becomes perfectly clear, as the water passes through the membrane, leaving pure oil behind. As shown in the microscope images, Solomon says, “We’re not only getting rid of the droplets you can see, but also smaller ones,” which contribute to the cloudy appearance.

    How much oil (weight/weight) can a piece of membrane hold on to? Can the oil be stripped off of the membrane so that the membrane can be reused? If the answers are "less than 1:1" and "no", this might still be useful as a final purification stage after most of the oil has been removed or for situations where you are trying to clear smaller amounts of more toxic materials.

    1. Re:Is this better for pour-over or French Press? by bobaferret · · Score: 1

      I was under the impression that the membrane was simply separating oil from water, but not holding onto anything. A mechanical process could simply wipe the oil from the membrane, while at the same time apply pressure to push the water through.

  3. These guys should team up with Kevin Costner by Anonymous Coward · · Score: 1

    Kevin Costner had a centrifugal separator that was highly efficient, but could not achieve clean enough water to be allowed to help with past oil spills. Mixing his system with this could get the total system efficiency needed to do significant recovery of spilled oil.

  4. Re:Better applications by mi · · Score: 1

    Mayonnaise is also one of earth's nastiest substances

    This is only true about factory-made mayonnaise. The original recipe is drastically different — but can not be stored for more than a few days. If you are willing to deal with such quickly-expiring product, you can make your own at home. Recipes abound.

    --
    In Soviet Washington the swamp drains you.
  5. Re:Maxwell's Daemon next? by Jason+Levine · · Score: 1

    Reverse that and you have the Dune shields. Block fast moving items but let slow moving ones through.

    --
    My sci-fi novel, Ghost Thief, is now available from Amazon.com.
  6. Already solved? by Anonymous Coward · · Score: 1

    Wasn't this issue already solved, there was I believe some competition a few years back after the gulf spill where several designs competed for prize money. One using a simple rig with rotating plastic disks with groves in them blew away the competition and went FAR beyond the requirements of the competition. Sounds like a lot easier & cheaper solution then some kind of nano material.

    http://gizmodo.com/5852606/a-4600-gallon-per-minute-oil-skimmer-just-won-the-14-million-x-challenge

    1. Re:Already solved? by tomhath · · Score: 2

      Here's a better discussion of skimmers. They certainly have their place and the Elastec design is very efficient.

      Skimmers work on a film of oil floating on the surface, not so much for oil that has already gone into suspension under the water. This filter seems to fit the latter scenario better

    2. Re:Already solved? by 517714 · · Score: 1

      Technically, yes, there are solutions. Politically, no, the Federal Government would not allow BP to deploy booms and skimmers that, being under foreign registries, might not be unionized. In hindsight, BP should have used them and appealed to Congress, the courts, and the American people for relief from the Executive Department's overreach.

      --
      The US government have made it clear that we have no inalienable rights; any we do not defend vigorously will be taken.
  7. Oil companies will be thrilled to hear this by DickBreath · · Score: 1

    They will no longer need to worry about oil spills. Many of those silly, and very expensive 'safety' precautions can now be avoided. Saving costs increases shareholder value.

    The only real drawback to this solution seems to be that the membrane's ingredients do not include ground up kittens and babies.

    --

    I'll see your senator, and I'll raise you two judges.
  8. Vanishing Problems by pubwvj · · Score: 1

    Left alone these problems have been vanishing according to recent reports. Nature is eating it up. I'm not suggesting spilling more oil, far from it, but rather to not panic quite so much.

    1. Re:Vanishing Problems by X0563511 · · Score: 1

      It's not vanishing, it's doing exactly what we don't want - dispersing into the biosphere.

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
  9. Re:Better applications by Bengie · · Score: 1

    Emulsion of oil(stuff I buy uses virgin olive oil), vinegar, egg yolk, and salt. I'm not quite sure how this is "nasty".

  10. Re:Better applications by DoofusOfDeath · · Score: 1

    Emulsion of oil(stuff I buy uses virgin olive oil), vinegar, egg yolk, and salt. I'm not quite sure how this is "nasty".

    I guess you'd need to watch the movie Undercover Brother. Its mayonnaise scene scarred me for life.

    And, the idea of uncooked egg still creeps me out, to be honest.

  11. Lab vs. Field by ThatsNotPudding · · Score: 1

    I read about this and I wish them well, especially when the membranes start to clog-up with real-ocean dirt and bacteria move in to build a cozy biofilm community.

  12. carpet... by jep77 · · Score: 1

    Now all we have to do is cover the sea floor with this carpet and lift it up whenever there's a need. Perfect!