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 frydried 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 convective heat transfer during the frying process are discussed (non-boiling, boiling, and low-boiling regime). A dimensionless formulation for estimating the convective transfer is proposed.

Numerical Simulation and Analysis of the Heat and Mass Transfer of Oil-Based Drill Cuttings in a Thermal Desorption Chamber

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Studi Literatur Pemanfaatan Campuran Minyak Jelantah Dan Plastik Untuk Meningkatkan Karakteristik Bakar Sampah Organik Dengan Metode Frying

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Analysis the fry-drying process of oily sludge sample

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