Mechanical and hydraulic properties of sludge deposit on sludge drying reed beds (SDRBs): Influence of sludge characteristics and loading rates
Propriétés mécaniques et hydrauliques des dépôts de boue à la surface des lits de séchage plantés de roseaux : influence des caractéristiques des boues et des charges
Résumé
This work was designed to study the hydraulic properties of sludge deposit, focusing on the impact of operating conditions (i.e. loads and feeding frequencies) on air entrance (aerobic mineralization optimization) into the sludge deposit. The studied sludge deposits came from six 2 m2 pilot-scale SDRBs that had been in operation for 50 months with three different loads of 30, 50, and 70 kg of SS m2 y1. Two influents were assessed (i.e. activated sludge and septage) presenting different characteristics (i.e. pollutant contents, physical properties. . .). Two experimental approaches were employed based on establishing the water retention curve (capillary pressure versus volumetric water content) and the hydrotextural diagram to determine the hydraulic properties of sludge deposit. The study obtained valuable information for optimizing operating conditions, specifically for efficient management of loading frequency to optimize aerobic conditions within the sludge deposit.