Feed Characteristics and Digester Operative Conditions as Parameters Affecting the Rheology of Digested Municipal Solid Wastes

摘要: The rheology of pre-composted and fresh organic fractions of municipal solid wastes (OFMSW) anaerobically digested in thermophilic range of temperature and different operative conditions is presented. Rheological properties are strongly influenced by feed characteristics and the biodEgradation achieved. The metabolization of complex substrates has been invoked to explain different behaviours. A semiempirical model of plastic viscosity with total volatile solids, organic loading rate removed and specific gas production before feeding is proposed. The fluid behaviour of OFMSW sludges where complex substrates exert a determinant role, is outlined by thixotropy and temperature effect.