Skip to Main content Skip to Navigation
Journal articles

Dimensionless Formulation of Convective Heat Transfer in Fry-Drying of Sewage Sludge

Abstract : Fry-drying is an alternative for heat and mass transfer intensification. The process reuses waste oil as a heating medium for drying by contact with the wet sludge. At the end of the process, a stable derived fuel is obtained, a granular solid composed of the dried indigenous sewage solid and the impregnated oil. The fry-dried sludge is storable and transportable without any pathogen elements. Knowledge about heat and mass transfer rates during the frying process is essential in order to assess the quality of the final product such as calorific value, oil uptake, porosity changes, etc. The heat transfer properties including transfer by free convection between the solid and the frying oil are fundamental for the process design and manufacturing of the fry-dried product. The convective heat coefficient by temperature measurement and overall energy balance calculation is determined. The heat flux is calculated from the fry-drying kinetics including moisture loss and oil intake kinetics. Various hydrodynamic regimes for convec-tive heat transfer during the frying process are discussed (non-boiling, boiling, and low-boiling regime). A dimensionless formulation for estimating the convec-tive transfer is proposed.
Complete list of metadatas
Contributor : Bruno Ladevie <>
Submitted on : Monday, December 11, 2017 - 11:48:54 AM
Last modification on : Wednesday, June 24, 2020 - 4:19:31 PM


Files produced by the author(s)



Bruno Ladevie, M. Romdhana, Didier Lecomte. Dimensionless Formulation of Convective Heat Transfer in Fry-Drying of Sewage Sludge. Chemical Engineering and Technology, Wiley-VCH Verlag, 2011, 34 (11), pp.1847-1853. ⟨10.1002/ceat.201100120⟩. ⟨hal-01651378⟩



Record views


Files downloads