Citation:
Nafsika Ganidi, Sean Tyrrel, Elise Cartmell. The effect of organic loading rate on foam initiation during mesophilic anaerobic digestion of municipal wastewater sludge. Bioresource Technology, Volume 102, Issue 12, June 2011, pp6637-6643.
Abstract:
The impact of increasing organic load on anaerobic digestion foaming was studied
at both full and bench scale. Organic loadings of 1.25, 2.5 and 5 kg VS m(-3)
were applied to bench-scale digesters. Foaming was monitored at a full scale
digester operated in a comparable organic loading range over 15 months. The
bench scale batch studies identified 2.5 kg VS m(-3) as a critical threshold for
foam initiation while 5 kg VS m(-3) resulted in persistent foaming.
Investigation of a full scale foaming event corroborated the laboratory
observation that foaming may be initiated at a loading rate of 2.5 kg VS m(-3).
Experimental findings on foam composition and differences in the quality
characteristics between foaming and non-foaming sludges indicated that foam
initiation derived from the combined effect of the liquid and gas phases inside
a digester and that the solids/biomass ultimately stabilized foaming. (C) 2011
Elsevier Ltd. All rights reserved.