One-Dimensional Mathematical Model for Solar Drying of Beds of Sludge

Abstract

A one-dimensional mathematical model for the description of solar drying of beds of sewage sludge is developed and implemented with the software Engineering-Equation-Solver. After the discussion of relevant literature, the assumptions and general conditions of the model are explained. Governing differential equations for heat and mass transport inside the sludge are derived, followed by a discussion about correlations used for the determination of surface transport phenomena and for the description of thermophysical properties. Numerical discretization is achieved locally through the Finite Difference Method and temporary through the Runge-Kutta-Method. Finally, a parametric analysis on the sludge drying process is carried out. The obtained results demonstrate the effect of ambient parameters such as solar radiation, airflow rate, gas temperature, geometric aspects etc. on the drying process. The developed model may be used for further prediction and estimation of drying characteristics under several conditions.

Effect of Steps Height and Glass Cover Angle on Heat Transfer Performance for Solar Distillation: Numerical Study

“…The sunlight can be converted into directly for thermal objectives, e.g. in solar chimney [8,9], air heating [10,11], solar dryers [12,13], solar water heaters [14][15][16]. Another interesting applications of the solar heat is solar desalination, which is studied in this study.…”

Computational modeling of biosludge drying

“…The use of numerical methods such as finite difference, finite element and finite volume analysis to describe sludge drying has produced a large number of models. However, the accuracy of numerical models can further be improved by more information about the surface heat and mass transfer coefficients, sludge properties, volume change during processes and sensitivity analysis for justifying the acceptability of assumptions in modeling (Siqueira et al, 2018;Bisceglia et al, 2013).…”

Development of mathematical model for vacuum cheese drying

“…Vacuum drying is used for chemical and food products, explosive and heat-sensitive materials. When drying in a vacuum chamber, the main heat is transferred to the material by radiation or conduction from the heating surfaces [5][6][7][8][9][10][11][12][13]. In practice, vacuum drying of food products is carried out in an air-proof heat-insulated chamber, equipped with heating elements connected to a vacuum line [14][15][16][17][18].…”