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

Abstract

The rheological behaviour of pasty sewage sludge is studied in relationship with the physicochemical composition and its time evolution. We show that the behaviour 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 behaviours 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 behaviour at any age, only by using simple tests to measure the master curve parameters.