[Terrapreta] Overview on biochar production methods

[Adriana Downie]

Jeff,

Quality of the gas is a whole separate issue. We do measurements before
and after our gas clean-up so we use the European tar sampling procedure
(which involves impinger trains, filters and gas meter) to 'drop out'
and larger chain hydrocarbons so they can be quantified and so they
don't foul up the analysers.  We then have a suite of gas analysers
including a GC. It is a reasonably expensive exercise to get set up and
maintain, but the only way to know what you have.

A straight hydrogen meter is cheaper and will tell you something,
perhaps a good place to start. Hydrogen however is often not the crux of
the energy content in a pyrolysis gas, so you may be left feeling like
you missed something. 

Adriana. 
BEST Energies

-----Original Message-----
From: Jeff Davis [mailto:jeff0124 at velocity.net] 
Sent: Friday, 17 August 2007 1:34 PM
To: terrapreta at bioenergylists.org
Subject: Re: [Terrapreta] Overview on biochar production methods

Hi Adriana


Adriana wrote:
> If you know the mass of the wood in and the mass of the charcoal out,
> then the balance will be what has volatilised into the gas phase so
you
> know the mass of gas out.

True but your gas quality can vary. It would be possible to have just
CO2
and N2. I like H2 rich gas.


>It is very hard to control yield in batch
> processes unless you bring down the temperature in a nitrogen
> environment to prevent combustion.

My process is continuous. I'm thinking the SV will control yield.


> Moisture content is easy to do yourself (if you have a scale).

I'm with you here. I did that with an old microwave oven and scales.
Sometimes my sample gets carbonized :)

I don't fell I do a good job with what I have to work with and it would
be
nice to out source some of this work.

Too costly but nice to check out:
Moisture Determination Balances
http://www.coleparmer.com/catalog/product_view.asp?sku=0100270


Thanks,

Jeff





-- 
Jeff Davis

Some where 20 miles south of Lake Erie, USA

_______________________________________________
Terrapreta mailing list
Terrapreta at bioenergylists.org
http://tech.groups.yahoo.com/group/biochar/
http://terrapreta.bioenergylists.org
http://info.bioenergylists.org