Drying of Porous Materials: Experiments and Modelling at Pore Level

  • L. A. Segura
Part of the Food Engineering series book series (FSES)

Drying of porous materials is important in the processing industry, mainly in food manufacturing. The classical drying theory has been widely studied (Barbosa-Cánovas and Vega-Mercado, 1996). This approach is based on experimental determination of the effective diffusion coefficients as a function of water saturation. A different approach is based on the study of drying mechanisms at pore level (Segura and Toledo, 2005a; Segura and Toledo, 2005b; Laurindo and Prat, 1998). Provided pore geometry, pore topology and wall composition of the porous medium, these coefficients can be predicted. In this work we studied isothermal drying of non-hygroscopic porous media with a mechanism based computer facilitated model of pore-level drying.

Simulation results of pore-level drying of non-hygroscopic rigid liquid-wet porous media are presented. Two and three-dimensional pore networks represent pore spaces.

Here, I report results of experiments and distributions of liquid and vapor as drying time advances. For the calculation of transport properties, details of pore space and displacement were subsumed in pore conductances (Segura and Toledo, 2005b). Solving for the pressure field in each phase, vapor and liquid, I found a single effective conductance for each phase as a function of liquid saturation. Along with the effective conductance for the liquid-saturated network, the diffusivity of liquid and diffusivity of vapor were calculated.


Porous Medium Pore Network Liquid Saturation Liquid Diffusivity Hydraulic Flow 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Barbosa-Cánovas, G., and Vega-Mercado H., 1996, Dehydration of Food, Chapman & Hall, New York.Google Scholar
  2. Laurindo J.B. 1996, Evaporation en Milieu Poreux. Etude Expérimentale sur Milieux-Modèles et Modélisation de Type Percolation, INPT Thesis, Toulouse.Google Scholar
  3. Laurindo, J.B., and Prat M., 1998, Numerical and Experimental Network Study of Evaporation in Capillary Porous Media Drying Rates, Chem. Eng. Sci., 53:12, 2257.CrossRefGoogle Scholar
  4. Segura, L.A., and Toledo P.G., 2001, Monte Carlo Simulations and Experiments of the Isothermal Drying of Porous Materials: Humidity Curves and Maps, in: Proceedings of III Congreso Iberoamericano de Ingeniería en Alimentos, Valencia.Google Scholar
  5. Segura, L.A., and Toledo P.G., 2005a, Pore-Level Modeling of Isothermal Drying of Pore Networks. Evaporation and viscous flow, Lat. Am. Appl. Res. 35:43.Google Scholar
  6. Segura, L.A., and Toledo P.G., 2005b, Pore-Level Modeling of Isothermal Drying of Pore Networks. Pore Shape and Size Distribution Effects on Saturation and Transport Parameters, Chem. Eng. J. 111:2–3, 237.CrossRefGoogle Scholar
  7. Shaw T.M., 1987, Drying as an Immiscible Displacement Process with Fluid Counterflow, Phys Rev. Lett. 59:1671.CrossRefGoogle Scholar
  8. Toledo, P.G., Davis, H T., and Scriven L.E., 1995, Hyperdispersive Flow Liquid Thin Films in Fractal Porous Media, Colloids Surf. 104:73.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • L. A. Segura
    • 1
  1. 1.Departamento de Ingeniería de AlimentosUniversidad del Bío-Bío ChillánChile

Personalised recommendations