Biofilm growth and hydraulic conditions in sewers
Résumé
The development of biofilm in sewers has been monitored using glass coupons placed on the walls. Two experimental sites, differing in terms of the particulate pollution transported by the wastewater and the wastewater velocity, were tested. The biofilm growth, measured by opacity and dry weight, is a function of the number of days the coupons have been really immersed in the wastewater. However the linear correlations which have been obtained between the amount of biofilm and the number of days in immersion are not valid anymore when the biofilm becomes very thick or when the number of days becomes large. In such cases, sloughing and detachment events, induced either by the biofilm over weight or by hydrodynamic stresses related to rain events, disturb the biofilm development.