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Author Topic: The extraction of large hydrocarbons as a contribution to global warming?  (Read 2890 times)

Offline Greg_Kaye

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We regularly hear people talking about car use in relation to global warming any yet we rarely hear people talking about plastics - which seems to be to be a bit surprising as plastics contain carbon too.

I am really curious to know more about the average contents of crude oil.  The ideal would be to get a breakdown in its contents in relation to the distribution of carbon atoms within various types of molecular form but as I have failed to get any clear information on the content of oil I realise that this may be a bit ambitious.

Up to now I have only got as far as to produce this bit of text:
"We can note that the combustion or decomposition of a single unit of styrene (the stuff of polystyrene and ABS) will result in the release of 8 carbon atoms (along with 8 atoms of hydrogen); the combustion or decomposition of a unit of polyvinyl chloride (PVC) will result in the release of 2 carbon atoms (along with three atoms of hydrogen and one of chlorine) and the combustion or decomposition of a unit of nylon 6,6 - as it's name suggests - will release 12 carbon atoms (along with 22 atoms of hydrogen, two atoms of oxygen and a couple of nitrogen's).
The global truth is that plastic is not cheap. Disposable and unnecessary plastics still have an undeniable ability to cheapen the individual and yet their overall cost may well be too great for humanity to bear. The cheapness of plastic has a definitely nasty side and this brings us on to considerations of the law of disposability. Anyone who thinks that we live in a disposable society must also think that we live in a disposable society."
(texts that range across a variety of related issues can be found at the "Attempts at Survival" website: newbielink:http://www.attempts.org.uk [nonactive] .  I will welcome any feedback on the content this and related sites).

It strikes me that the plastics issue may be of great significance.  The process of refining plastics requires the oil to be heated to high temperatures and, as such, must require a considerable consumption of energy in itself and, as a result, it seems to me that it would make sense if the lighter hydrocarbons could get boiled out of the oil so that the remaining sludge could be chucked back into the various spent wells.

Those are my thoughts so far.

How significant is the plastics problem and how can it be tackled?


 

Offline Bored chemist

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Most oil aproximates fairly well to two hydrogens for each carbon repeated to produce long chains.
Apart from natural gas the fraction of carbon in all petroleum products is fairly near 12/14 or about 86%.

Since most oil is burned in the end it doesn't matter much if some is turned into plastic first.
That's not to say that plastics are unimportant; it would help a lot if they all got recyled.
 

Offline litespeed

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Greg - Chemist is correct. Fossil hydrocarbon products generally end up being burned. One major exception is asphalt used in road contstruction.  However, there is a significant plastics recycling industry, but it is not significant enough to measurably reduced fossil fuel extraction by any significan measure.

 

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