[Digestion] Nitrogen Emissions from Biogas

[David Fulford]

Tom and listers,

The experience of the Indian biogas programme is that anaerobic digestion 
locks up nitrogen in a form that is available to plants, but is not leached 
out by water. The key to this is sufficient fibre - lignin. The lignin 
fibres swell and form a sponge that absorbs water and nitrogen. I have just 
been visiting SKG Sangha in Bangalore (on behalf of Ashden Awards), who 
have been making family size digesters. The effluent slurry is absorbed 
into leaves, straw and other such material and forms an excellent compost. 
It retains water and nitrogen and enhances growth of crops.

The key to nitrogen emmision reduction is to process it properly.

David Fulford

On Mar 8 2007, Tom Miles wrote:

>We have had an inquiry from a concerned farmer in Washington state (US)
>about the promotion of biogas digesters for dairy use.  His impression is
>that "Such a  dairy waste water and solids treatment system is a prolific
>emitter of N20."
> 
>His question:"Does anyone have any citations for N20 emissions from a 2000
>cow dairy manure digester? How does such a digester compare to say a 100 mw
>coal plant?"
> 
>How can nitrogen emissions from digestors be captures for use in
>agriculture?
> 
>Where can we find answers to these questions?
> 
>Thanks
> 
>Tom Miles
> 
>_______________________________________________
>Digestion mailing list
>Digestion at listserv.repp.org
>http://listserv.repp.org/mailman/listinfo/digestion_listserv.repp.org
>