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SkepticJ
2009-Feb-27, 10:57 AM
I've been thinking recently about the end of fossil oil. I'm not worried about it being gone as a fuel; we'll have switched to other sources of energy. I'm concerned about it being gone as a feedstock.

We need plastic. Bioplastic will fill many roles that petrol-plastic is used for today, but it can't (at least that I'm aware) replace all petrol-plastic. Why? Well, it biodegrades. In the case of shopping bags, six-pack rings and disposable cups this is naturally a good thing.

Petrol-plastic's vice is its virtue. Imagine a world without rot-proof plastic. PVC pipes gone, epoxy, modern medical supplies, car parts, boat hulls, gore-tex, polycarbonate resin... scary, eh?

Thankfully physics doesn't preclude making oil faster and better than geology does it. http://en.wikipedia.org/wiki/Thermal_depolymerization

In principle it's possible to replace. Demand for oil as a feedstock is going to continue to rise though. I wonder if we've got the time to get the infrastructure up, or if there'll be a pinch decades out.

Chuck
2009-Feb-27, 01:54 PM
We're not totally out of oil. It will last longer if we stop burning it as fuel.

NEOWatcher
2009-Feb-27, 02:36 PM
We're not totally out of oil. It will last longer if we stop burning it as fuel.
Yes; but I think the point of the post was "how long?".
I recall some large percentage of oil being used for plastics and other non-energy uses. 40% sticks in my head for some reason.

So; even if we eliminate the current fuel uses, we extend the life by 250%. I'm not sure if that's entirely a comfortable margin. But; could it be given the expected technology that will replace these other uses?

Are there any uses that we have now that don't seem replaceable or feasable in the near future?

Fazor
2009-Feb-27, 04:36 PM
There's a particular brand of bottled water that we buy that says the bottle is made from corn rather than oil. I don't know the specifics because I've never bothered looking into it, but in that application, the bottle looks, feels, and holds up for my use as a consumer just as well as any other plastic bottle.

I'm not sure if they don't use oil products at all (ignoring powering the plant) or if they just use less or what; and I don't know if it can be adapted for other kinds of plastics. Thats' for you chemists to figure out. :)

Argos
2009-Feb-28, 01:31 AM
I've been thinking recently about the end of fossil oil. I'm not worried about it being gone as a fuel; we'll have switched to other sources of energy. I'm concerned about it being gone as a feedstock.

Most of the oil [96% according to estimates I´ve heard about] is used for fuel. When people talk of peak oil, end of oil, they´re basically talking of [cheap] oil for use as fuel. After oil becomes too difficult [ergo expensive] for being extracted in large scale for use as fuel, there will still be a lot of it to be used as feedstock for plastics. Of course it will be expensive, but it will be there, to be extracted in relatively small amounts for industrial processing, while the world goes electric.

Ronald Brak
2009-Feb-28, 01:46 AM
After an oil field is exhausted, stripper wells can continue to pump out small quantities of oil each day and can continue to do so for potentially hundreds of years. This oil could be used for plastic feedstock if desired. And then there is the vast amount of disgusting filth trapped in tar sands and oil shales. We won't run out of oil for plastics anytime soon, but it may end up cheaper to use other sources of material make plastic. People have also gone through the trouble to make a variety of substitutes for plastic that could be used such as liquid wood that can be moulded.

HenrikOlsen
2009-Feb-28, 07:28 AM
We won't run out of oil for plastics anytime soon, but it may end up cheaper to use other sources of material make plastic.
Simple supply/demand maths say that it will definitely at some time become cheaper to use other sources if plastics use don't stop entirely first.

novaderrik
2009-Feb-28, 09:33 AM
George Carlin had an interesting take on plastics...
in one of his routines, he said that mother earth put humans on earth to make plastic, and once she has enough plastic, she will wipe us off the face of the planet.
actually, he said the one true God- either Joe Pesci or the giant Electron, depending on how you interpret it- put us on earth to create the plastic...

Chuck
2009-Feb-28, 03:47 PM
Yes, life is just an intermediate step in the plastic manufacturing process of the gods. They might be highly intelligent if then can anticipate their Tupperware needs billions of years in advance.

mugaliens
2009-Feb-28, 09:36 PM
We need plastic. Bioplastic will fill many roles that petrol-plastic is used for today, but it can't (at least that I'm aware) replace all petrol-plastic. Why? Well, it biodegrades.

Remember that Monsanto jingle at Walt Disney World Tomorrowland exhibit?

"Better Living Through Chemistry"

Just because it's organic doesn't mean it's biodegradeable, particularly after the chemists pull a few tricks with it.

Doodler
2009-Feb-28, 10:44 PM
I've been thinking recently about the end of fossil oil. I'm not worried about it being gone as a fuel; we'll have switched to other sources of energy. I'm concerned about it being gone as a feedstock.

We need plastic. Bioplastic will fill many roles that petrol-plastic is used for today, but it can't (at least that I'm aware) replace all petrol-plastic. Why? Well, it biodegrades. In the case of shopping bags, six-pack rings and disposable cups this is naturally a good thing.

Petrol-plastic's vice is its virtue. Imagine a world without rot-proof plastic. PVC pipes gone, epoxy, modern medical supplies, car parts, boat hulls, gore-tex, polycarbonate resin... scary, eh?

Thankfully physics doesn't preclude making oil faster and better than geology does it. http://en.wikipedia.org/wiki/Thermal_depolymerization

In principle it's possible to replace. Demand for oil as a feedstock is going to continue to rise though. I wonder if we've got the time to get the infrastructure up, or if there'll be a pinch decades out.


Color me skeptical, given that crude from the ground is nothing more than the same kind of matter as the new organic crudes, just older by epochs, why is it you'd think that bioplastics can't be made not to degrade over time, and vice versa?

SkepticJ
2009-Mar-01, 07:04 AM
Color me skeptical, given that crude from the ground is nothing more than the same kind of matter as the new organic crudes, just older by epochs, why is it you'd think that bioplastics can't be made not to degrade over time, and vice versa?

That's not true. They're both organic (I use this in the strict chemical sense - hate the co-opting of the word by yuppies), but chemically they're different. Alkyl esters, triglycerides etc. (what I guess you mean by "organic crude") don't look like petroleum.

I don't think they cannot, but I don't think it's wise to assume that rot-proof polymers as good as the ones we've got can be developed. When chemical engineers can make aramid, epoxies*, teflon, polycarbonates, polyamides... from chemicals directly derived from corn, algae or whatever, then there's nothing to be concerned about.

Polylactic acid is what Fazor's water bottle was probably made from. Fantastic stuff. It will rot, but the conditions under which it will do so are rather extreme--60 °C for over a week in a composting machine. Just about any food product subjected to such extremes would be most foul. So seems logical to use it for such roles, and not waste the precious petrol on stuff we're going to throw away.

*Not only are they fantastic glues, but fiberglass and carbon composites aren't possible without them. Where would the aerospace, watercraft and wind-turbine industries be without epoxy?

SkepticJ
2009-Mar-01, 11:25 PM
Yes; but I think the point of the post was "how long?".
I recall some large percentage of oil being used for plastics and other non-energy uses. 40% sticks in my head for some reason.

Thankfully it's not that much. This government site http://www.eia.doe.gov/neic/infosheets/petroleumproducts.html has it at 5%.
I've seen other sources give a figure as high as 15% though.