title: Simultaneous effect of initial moisture content and airflow rate on biodrying of sewage sludge.
abstract: The simultaneous effect of initial moisture content (initial Mc) and air-flow rate (AFR) on biodrying performance was evaluated. For the study, a 3(2) factorial design, whose factors were AFR (1, 2 and 3 L/min kg(TS)) and initial Mc (59, 68 and 78% w.b.), was used. Using energy and water mass balance the main routes of water removal, energy use and efficiencies were determined. The results show that initial Mc has a stronger effect on the biodrying than the AFR, affecting the air outlet temperature and improving the water removal, with higher maximum temperatures obtained around 68% and the lowest maximum matrix temperature obtained at initial Mc = 78%.Through the water mass balance it was found that the main mechanism for water removal was the aeration, with higher water removal at intermediate initial Mc (68%) and high AFR (3 L/min kg(TS)). The energy balance indicated that bioreaction is the main energy source for water evaporation, with higher energy produced at intermediate initial Mc (68%). Finally, it was found that low values of initial Mc (59%) improve biodrying efficiency.
authors.affiliation: Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile. Electronic address: cesar.huilinir@usach.cl.
authors.forename: Cesar
authors.initials: C
authors.lastname: Huiliñir
authors.affiliation: Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile.
authors.forename: Manuel
authors.initials: M
authors.lastname: Villegas
mesh_terms: D000392:Air Movements; D001673:Biodegradation, Environmental; D003890:Desiccation; D012722:Sewage / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D012722:Sewage; D014867:Water
keywords: Air flow rates; Biodrying; Energy balance; Initial moisture content; Water mass balance