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Burning Plastic Bags

  1. Apr 25, 2010 #1
    My question is that would it be more environmentally friendly to burn plastics bags rather than letting them degrade? They take thousands of years to do so and even then many plastics do not completely break down beyond the molecular level...so instead of letting them hang around in the environment why do we not just burn them? Plastics are mainly made of hydrocarbons, so burning them would release (mainly) carbon dioxide and water. Again I'm talking about the majority of plastics.
     
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  3. Apr 25, 2010 #2

    Borek

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    Define environmentally friendly. Plastic that slowly degrades to water and carbon dioxide is not necessarily dangerous to environment - so why burn it and increase carbon dioxide emission?
     
  4. Apr 25, 2010 #3
    Depending on how you burn it it won't neccesarily be complete combustion, which means production of carbon monoxide.
     
  5. Apr 25, 2010 #4
    Currently, majority of our waste that does not end up in landfills, ends up in the oceans. There the plastic is bleached and broken down into smaller and smaller granules. This is then swallowed by small fish and the higher you go up the food chain the more plastic fish/oceanic life contain. This stuff is toxic to them. In addition in this form plastics can't be utilized by microbes and degraded..but if burnt plants could use the carbon dioxide etc... By burning we make the constituents of plastic available for life to utilize much faster instead of littering the planet and polluting our oceans.
     
  6. Apr 26, 2010 #5

    Borek

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    Plastic that ends in the oceans lands there not because it wasn't burnt, but because it was thrown away where it shouldn't be. So before burning it, you have to collect it - and once it is collected it can be safely put in landfills, it doesn't have to be burnt. Even better will be to reuse it after collecting.

    Simple plastics - like polyethylene - are not toxic. They can be made toxic by plasticizers or dyes, but if these substances are present in plastic, it usually means that burning it cleanly and safely is much more difficult.

    I don't mean that burning plastics is an absolutely bad idea, but before trying we should take a lot of factors into account, to be sure that solution is properly addressed and is not worse than the problem itself.
     
  7. Apr 26, 2010 #6
    Is there a specific reason to consider burning rather than recycling?
     
  8. Apr 27, 2010 #7

    alxm

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    Recycling is better than burning. Both are better than landfill/nothing.
    Burning plastic gives up to 80% of the oil equivalent.

    So until we've abolished the practice of burning oil, burning plastic is no big deal IMO.
     
  9. Apr 29, 2010 #8
    How many times can you recycle a plastic bag? And how safe is the plastic in landfills, etc...? The viewpoint I take for burning is that by burning the plastic, the constituents are readily put back into the bio/chem cycle of the planet. Whereas on the otherhand if plastic just remains in its normal form it just breaks down into smaller and smaller pieces and take a very very long time to degrade....Sure burning it would release CO2 into the atmosphere but that would be better than poisoning marine and other animal life...
     
  10. Apr 29, 2010 #9

    Borek

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    Do you have any data to support that claim?

    --
     
  11. May 2, 2010 #10

    ShawnD

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    Burning plastic is only good is if it's burned at high temperatures with a lot of oxygen. This is true for almost all hydrocarbons. You can test this by looking at how much smoke comes from your car (none) vs how much smoke comes from burning gasoline in a tin can (lots).

    Lots of garbage is already burned to create electricity, and it's very clean when done properly.
    http://discovermagazine.com/2007/may/the-ultimate-garbage-disposal

    Recycling plastic is difficult because things like polystyrene should not be mixed with polyethylene or polyurethane, and the recycled plastic is often lower quality and more expensive than new plastic. Burning plastic is easy because polystyrene, polyethylene, and polyurethane can be mixed together, color doesn't matter, and the energy it produces is just as good as energy produced from any other power plant. Using the plastic for energy is also more cost effective.
     
  12. May 2, 2010 #11
    Do you know what temperature plastic would have to be burned at to produce less smoke?
     
    Last edited by a moderator: Jan 11, 2014
  13. May 2, 2010 #12
    Let's not endorse something that is equivalent* to a practice we are trying to abolish.

    *or worse, if it just un-sequesters 20% more carbon
    Indeed. If one's motivation is marine well-being (rather than just knee-jerking to the cause that presents the most emotionally engaging simplistic photographs), and even (implausibly) assuming all landfill-plastic somehow escapes into the ocean, it's not clear that bits of plastic threaten the existence of any species as dramatically as the rapid acidification caused by our "terraforming" emissions threatens entire ocean ecosystems.
     
    Last edited: May 2, 2010
  14. May 14, 2010 #13
    All of us know that burning plastics can damage our ozone layer but still everyone ignores that and how about the plastic bottles, toys, and vessels? Is there a way on how to segregate them properly without burning them?
    I'd read an article about segregation of this plastic by means of cornstarch. Yea! starch! Just put the starch in the plastic and that's it. The bacteria will eat the starch and so on the plastic.
     
    Last edited by a moderator: Jan 11, 2014
  15. May 16, 2010 #14

    DaveC426913

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    I've never heard of burning garbage and producing toxic byproducts described with such a positive spin!

    Seriously, they're pollutants in that form; we don't really want them back in the system.

    But if they must go back into the system, it is better to release them over a longer time, so that the affected ecology has time to absorb them.
     
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