Hello all, I had made an inquiry about lithium tracer tests in biogas digesters some time ago. Somebody from the Netherlands offered me friendly advice on this topic. However, I've dumped that email by accident, and would be glad if the respective person could reestablish a contact. If anybody else does have experience with such experiments, please reply. My second question is about methods to measure flow velocities and assess the flow field in stirred biogas digesters. Ultrasonic is not applicable due to very low penetration of the respective substrates (slurry + other biosolids). Regards, Mathias ********************************************** Mathias Effenberger Bayerische Landesanstalt fuer Landtechnik Am Staudengarten 3 85354 Freising GERMANY phone: +49 8161 71-5157 fax: +49 8161 71-4363 email: effenberger@tec.agrar.tu-muenchen.de Digestion List Archives: http://www.crest.org/discussion/digestion/current/ Digestion List Moderator: Paul Harris, paul.harris@adelaide.edu.au http://www.roseworthy.adelaide.edu.au/~pharris List-Post: <mailto:digestion@crest.org> List-Help: <mailto:digestion-help@crest.org> List-Unsubscribe: <mailto:digestion-unsubscribe@crest.org> List-Subscribe: <mailto:digestion-subscribe@crest.org> Other Digestion Events and Information: http://www.bioenergy2002.org http://solstice.crest.org/renewables/biomass-info/ Beginners Tour of Biogas http://WWW.roseworthy.adelaide.edu.au/~pharris/biogas/beginners