Rhéologie et physico-chimie des boues résiduaires pâteuses pour l'étude du stockage et de l'épandage

Rheology and physico-chemistry of pasty sewage sludge in view of storing and spreading

Cemagref Domaine des Palaquins 03150 Montoldre

Abstract

The rheological behavior of pasty sewage sludge is studied in relation ship with its physicochemical composition and its time evolution. We show that the behavior can be systematically described in three regions, separated by two critical stresses, even if fermentation process occurs. Nevertheless, it appears that only non-hydrodynamic interactions change with time of storage : this implies that the steady state behaviors of a sludge at different ages are similar. The corresponding flow curves can be rescaled along a master curve from which one can determine the sludge behavior at any age, only by using simple tests to measure the master curve parameters.