Effects of lipids on thermophilic anaerobic digestion and reduction of lipid inhibition upon addition of bentonite.
The effect of bentonite-bound oil on thermophilic anaerobic digestion of cattle manure was investigated. In digestor experiments, addition of oil was found to be inhibitory during start-up and the inhibitory effect was less pronounced when the oil was added in the form of bentonite-bound oil compared to when the oil was added alone. After adaptation of the digestors, very rapid degradation of oil was observed and more than 80% of the oil was degraded within a few hours after daily feeding. In batch experiments, glyceride trioleate was found to be inhibitory to thermophilic anaerobic digestion when the concentrations were higher than 2.0 g/l. However, addition of bentonite (a clay mineral) at concentrations of 0.15% and 0.45% was found to partly overcome this inhibition. Addition of calcium chloride in concentration of 3 mM (0.033% w/v) showed a similar positive effect on the utilization of oil, but the effect was lower than with bentonite.
Department of Biotechnology, Technical University of Denmark, Lyngby.
I
I
Angelidaki
S P
SP
Petersen
B K
BK
Ahring
D000693:Anaerobiosis; D000818:Animals; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism*; D001546:Bentonite / Q000494:pharmacology*; D002417:Cattle; D006868:Hydrolysis; D008055:Lipids / Q000494:pharmacology*; D008372:Manure
D008055:Lipids; D008372:Manure; D001546:Bentonite