As far as I know, in the EU and especially Nordic countries where digestate is used as a biofertilizer, regulations only require pasteurization of abattoir waste?
In South Africa where we are operating, sludge management guidelines require pasteurization of sewage sludge. Pasteurization is generally considered not necessary if you use a thermophilic high temperature AD process. Regards Mark _____ From: [email protected] [mailto:[email protected]] On Behalf Of Alexander Eaton Sent: 13 July 2011 10:54 PM To: For Discussion of Anaerobic Digestion Subject: Re: [Digestion] pathogens which might create a health hazard Just to add a dimension to this conversation, are the true risks of pathogens in the digester effluent so high as to justify pasteurization? I understand that the majority of the microbiotic activity in effluent to be a positive addition to the soil. I ask because so many government officials seem to fixate on this point, when I have not really seen data that shows high enough probability of dangerous pathogens to justify extreme measures. The smallish risk seems reasonable for the benefits of a more living organic fertilizers. Obviously the input material has a lot to do with this aspect, but generally I am interested to hear responses. Cheers A On Wed, Jul 13, 2011 at 1:55 PM, Johan Carels <[email protected]> wrote: Dear Johan, Regarding pathogens which might create a health hazard. There are reports on pathogens for man, animal, and plant, which might survive the biogas process. As the input material of any biogas plant which is not operated on a farm level may contain many different types of pathogens you may accumulate these germs even if they are in a low number in the digestate. Suggest to pasturise ( heating at 70°C during 60 minutes) all the digestate since you hav e this heat available from the cogenerater [cooling water, turbocooling, exhaust gase-heat]. This will kill all pathogens. K rgds Johan Carels www.jcarels.be _______________________________________________ Digestion mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/digestion_lists.bioenergyli sts.org for more information about digestion, see Beginner's Guide to Biogas http://www.adelaide.edu.au/biogas/ and the Biogas Wiki http://biogas.wikispaces.com/ -- Alexander Eaton Sistema Biobolsa IRRI-Mexico RedBioLAC Mex cel: (55) 11522786 US cel: 970 275 4505 [email protected] [email protected] sistemabiobolsa.com www.irrimexico.org www.redbiolac.org No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.901 / Virus Database: 271.1.1/3762 - Release Date: 07/13/11 08:34:00
_______________________________________________ Digestion mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/digestion_lists.bioenergylists.org for more information about digestion, see Beginner's Guide to Biogas http://www.adelaide.edu.au/biogas/ and the Biogas Wiki http://biogas.wikispaces.com/
