P2269@com.qz.se ("ENG-LEONG FOO ", MIRCEN-STOCKHOLM) (04/04/89)
The composition of biogas which is generated during methane fermentation can vary and to certain extent also with the type of substrate used. Could you (Jon Iza, Environ Eng. Prog. Univ of Mass.) please elaborate further on the criteria for setting the limits for the different gases; are they different for the same substrate but different reactors; what triggers changes in the gas composition? To Other Readers: ---------------- Is there anyone who has knowledge in online warning systems for fermentation processes ? The indicator could be a gas, pH change, etc. I wonder if there are developed systems where action to a warning signal (relayed to the researcher's home) could be corrected by a terminal link-up from home to the host computer at the lab. ? This would certainly be welcomed by researchers as well as the industry. From: Eng-leong Foo, MIRCEN-Stockholm, Sweden
P2269@com.qz.se ("ENG-LEONG FOO ", MIRCEN-STOCKHOLM) (04/07/89)
To Jon Iza (Univ of Mass. U.S.A.) What gases are you monitoring as indicators for your early warning system in anaerobic reactors ? From: Eng-leong Foo (MIRCEN-STockholm, Sweden)
IZA@ecs.umass.edu ("Jon Iza, Envir.Eng.Program UMASS") (04/09/89)
Subject: On-line gas monitoring for AD The monitored gases are Hydrogen and Carbon Monoxide. Both are trace gases, with typical levels in the order of ppm for H2 and ppb for CO. Reactor upsets produce big increases in H2 concentration, but the changes are rather fast and inconsistent. The simultaneous measurement of CO concentration helps to screen the data and get a good feeling of what is going on. We here (Prof. Switzenbaum, E. Giraldo and I) we are trying to create a big database of information collected during experiments with spikes of toxicants and/or organic and hydraulic overloads, to get a better knowledge of the process.
P2269@com.qz.se ("ENG-LEONG FOO ", MIRCEN-STOCKHOLM) (05/17/89)
I have read Robert F Hickey's paper that was published recently in Water Research (1989, No.2) on "The effect of heavy metals on methane production and hydrogen and carbon monoxide levels during batch anaerobic sludge digestion". I find this an interesting paper. If there are a sufficient number of people who are also in this interested in paper, we might consider using it as a discussion paper. Q: To: Jon Iza - Is Robert Hickey still at Amherst or has he moved to the Michigan Biotechnology Institute ? From: Eng-leong Foo, Stockholm
IQTE0@ccuab1.uab.es (05/24/89)
I agree Hickey's paper related to on-line monitoring of biogas composition could be an interesting topic of discussion. I would be interested. Josep M. Paris, Barcelona, Spain.