[Digestion] heating the fermenter

[adkarve]

Thanks, Mr. Martin. This explains why biogas technology is not used in
countries having cold climate.
Yours
A.D.Karve
----- Original Message -----
From: Duncan Martin <duncanjmartin at eircom.net>
To: adkarve <adkarve at pn2.vsnl.net.in>; <Digestion at listserv.repp.org>
Sent: Tuesday, October 31, 2006 4:05 PM
Subject: Re: [Digestion] heating the fermenter


> Heat IS generated but so slowly that it is a very minor factor in most
> digesters.
>
> The dominant factors in the heat balance tend to be:
> - heat losses to the air and ground (except in VERY warm climates or with
> VERY good insulation or at VERY large scale)
> - heat losses in the digestate (maybe offset by using it to preheat cold
> feedstock)
> - heat losses to the feedstock (it is often well below the digester temp
and
> if it isn't very strong you'll be adding a large volume every day) OR
> - heat gains from the feedstock (if it's hot - but that's much rarer)
> - any compensating heat input from a source of waste heat (sometimes
> available in industry)
> - finally the balancing heat input from burning of some of the biogas (a
> waste of good fuel but often unavoidable)
>
> Best regards
>
> Duncan J Martin
>
> Chair
> Republic of Ireland Centre
> Chartered Institution of Wastes Management,
>
> ================================
> CONTACT DETAILS
> Duncan J Martin, PhD, CEng, CSci, MIEI, MCIWM, MIChemE
> 24 Townsfield, Cloughjordan, N Tipperary, Ireland
> Mobile: +353 86 8377 906
> Email: duncanjmartin at eircom.net
> ================================