[Bioconversion] methane digester and greenhouse gasreductionfordemonstration post-carbon world home

[Paul Harris]

G'day All,

Thanks AJH, it IS biased as I was in a hurry (as usual).

AD is only suitable for "readily degradable" organic matter, for
woody/more durable material you could use gasification or grow fungii.

Gaseous fuels are NOT suitable for transport, as so much energy is used
in compression (you could use variable volume storage for short range
work)!

The carbon left in digester sludge is partly what makes the "good
organic fertiliser", as some organic C needs to go back to the soil so
we are not simply mining centuries of humus collection.

We always need to look at the "system" rather than just one "unit" of a
system!

All the best,
HOOROO

AJH wrote:
> 
> On Wed, 13 Jun 2007 11:53:23 +0930, Paul Harris wrote:
> 
> >Anaerobic destruction, which can be low tech/simple, gives of methane,
> >which should be used as fuel (high grade heat)
> 
> I'm all for fighting your own corner Paul but this is biased. It looks
> to me like, other than oils, biogas is the simplest of the biomass
> derived renewables to be converted in an engine to give motive power.
> Not only is it high calorific value but it is also relatively simple
> to clean.
> 
> > and leaves a good organic
> >compost.
> 
> And there's the rub, digestion is best for plants which haven't become
> "woody", the digestion process favours simple carbohydrates.
> 
> Even then how much carbon (the carbon being a measure of the fuel
> available in a carbohydrate) is left in the residue of an economic
> digester?
> 
> Has anyone any figures for digestion of grass silage?
> >
> >Combustion gives heat and ash/smoke, which has little organic material
> >but does contain plant nutrition and smoke is an eye/lung irritant.
> 
> Poor combustion gives smoke.
> 
> Combustion destroys plant available nitrogen compounds and dumps
> phosphorus ones into the atmosphere.
> 
> AJH
> 
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-- 
Mr. Paul Harris
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