Only Fuels and Horses

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Chris Waite Chris Waite
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Only Fuels and Horses

OK Chaps

For that eco-generator that is not going to keep me awake all night charging your eco-batteries on the raid. How about some eco-fuel:

http://www.flixxy.com/convert-plastic-to-oil.htm

You jest

I cannot believe that melting and progressing on to distil a mass of assorted household packaging plastic will produce some docile oil that will subsequently allow itself to be conveniently fractionated out into Petrol, Diesel and Paraffin.  (Unless you put it in a dish on your doorstep and set light to it; what's that about?)

Also, the maths is questionable - so your oil was first converted into plastic, then turned back into oil, which you burn - that much oil still ends up as carbon dioxide, so apart from spending some time as plastic, with the additional energy to convert it to plastic and back to oil, where is the 80% saving?

Better than putting it back in the ground where you got it from, I suppose?

Bring on the dioxins

CW
Paul (admin) Paul (admin)
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Re: Only Fuels and Horses

It hinges on the calorific value of 1L of oil.  It took 1kWh of electricity (which emits 0.57kg of CO2 from the UK power stations) so if you can get much more than 1kWh of useful energy from 1L oil it makes sense to turn the scrap plastic into oil.

Did you know that a lot of plastic is recycled anyway? It is shredded then heated ready for injection moulding. Many car parts use recycled plastic for example.

The CO2 saving is probably working on the principle that scrap plastic is buried and forgotton. But it doesn't matter which spin you put on it, burning fossil fuel products increases CO2 concentration in the air.

Its probably better to recycle scrap plastic into something useful. Better still stop producing all that useless, annoying plastic packaging in the first place.

-Paul
Timmo Timmo
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Re: Only Fuels and Horses

First I'll leave aside the debate about whether CO2 is linked to global warming and I'll waffle here on the basis that reducing CO2 in the atmosphere is a good thing.

Obviouslly there was a time on earth when there was a huge volume of trees and other vegetation which captured vast quantites of carbon and locked it away as coal, oil and gas.

It appears the increase in CO2 in the atmosphere is largely due to the way we dig up that carbon that has been safely stored away for millions of years (coal, oil, gas) and burn it so it becomes CO2. Meanwhile we reduce the number of trees which are one of the most efficient mechanisms for capturing that CO2 and converting it back to carbon (and oxygen.) 

If reducing the CO2 in the atmosphere is the goal than 'sequestering' carbon based materials is the better strategy, So, rather than burning wood (or even allowing it to rot) which has drawn carbon from the atmosphere as it grew it's better to incorporate it into houses, boats etc. and preserve it. The 'green' argument for burning wood is simply that it's a zero sum in the medium term. Burn wood, release CO2, grow tree, capture CO2 and convert back to carbon.

Now I'm not entirely sure of the chemical composition of plastics but they are made from oil so I'm assuming they are carbon based. This means that burying plastics is a way of sequestering that carbon (taking it out of circulation and locking it away again.) Turning that plastic into a fuel and burning it will release it into the atmosphere.

Clearly there are other arguments against burying plastics and, if we are going to dig up the carbon in the first place it is probably a good idea to make maximum use of it rather than dig up more.

There's a good book called 'How Bad are Bananas' by Mike Berners-Lee which explores the whole theme in a very clear and very understandable way (and he's a friend so I'd like his book to sell even better than it already has!)

Having said all that I've just spent a week working with some geologists (Polish, Swedish, Russian and Libyan) and they were universally scathing about the evidence linking global warming and CO2. Yes there's global warming, but (they say) man is arrogant to think he caused it and even more arrogant to think he can stop it though each of them admitted to having promoted the idea that there was possibly a link between CO2 and warming because they said it was the only way any request for research funding will be considered these days. In fact, a couple of them likened the political and marketing "hyoe" (their word) to the time when radiation was thought to be a miracle cure for everything and you could buy all sorts of radiactive products, or the time before smoking was recognised as bad and doctors would recommend a cigarette brand as a cure for throat problems. They were all very persuasive and, in their field, very senior, experienced and well respected.

Mind you, they were all quite happy to agree that reducing carbon consumption and sequestering carbon would reduce acid rain and other pollution and that it was something we should do anyway, regardless of any link with global warming. 

It's all very confusing! But I'll stick to wooden boats, it might do some good and they look nice too.

Timmo


On 18 Feb 2012, at 22:30, adminHBBR [via UK HBBR Forum] wrote:

Its probably better to recycle scrap plastic into something useful. Better still stop producing all that useless, annoying plastic packaging in the first place.

-Paul

momist momist
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Re: Only Fuels and Horses

Leaving aside the rights and wrongs of the CO2 debate, the only thing that will reduce CO2 output would be to stop digging the stuff (coal, oil and gas) out of the ground.  No amount of bio-fuels, recycling of plastic or any trading of carbon credits, let alone changing your light bulbs, will achieve this while there is a profit to be made by digging it up.
Anders Anders
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Re: Only Fuels and Horses

This is a wonderfull thread and one of the reasons I follow this forum. Totally  off topic but really interesting and with some very personal arguments.
Chris Waite Chris Waite
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Re: Only Fuels and Horses

I was rather hoping Jeremy might butt in here somewhere

And tell us why the melting and distillation of general household wrapping plastic would, or wouldn't work.  But I guess he has been waylaid by planners who, like some mutant, carnivorous insects, are currently entombing him in a hideous concoction of restrictive papier-

Mache, of course

CW

(Actually, are you there Jeremy?  Because if you keep an eye on 'Evolving Polly Wee', I am shortly going to be asking some engineering questions)
Jeremy Jeremy
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Re: Only Fuels and Horses

Sorry for the delay - you guessed correctly; planners (well, more specifically the bloody EA and flood risk zones.....) have been somewhat vexatious of late.

In general terms taking big molecules apart to make smaller ones needs a lot of energy.  Plastics are pretty much the biggest molecules around, so the breaking them down into smaller hydrocarbon molecules that can be more easily used as fuels doesn't seem that sensible.  It may well be viable in a place like Japan, though, where landfill is expensive and energy costs may make the conversion costs less significant.