Using an Overall Mass-Transfer Coefficient for Prediction of Drying of Chilean Coigüe


  • Rubén A. Ananias
  • William Broche
  • Mara Alvear
  • Carlos Salinas
  • Roger B. Keey


Drying rate, overall mass-transfer coefficient, coigüe, <i>Nothofagus dombeyi</i>


A phenomenological model was used to quantify the drying process of Chilean coigüe (Nothofagus dombeyi). This model is based on an overall mass-transfer coefficient, K, which was determined in four laboratory drying runs. The model suitably described the drying of Chilean coigüe lumber of 19- and 30-mm thickness with K ranging from 0.012 to 0.021 ms-1 at a dry-bulb of 60°C and a wet-bulb of 40°C. A preliminary industrial run under somewhat similar conditions in a 100-m3 industrial kiln with 38-mm-thick lumber showing that the drying process could be represented by a K of 0.008 ms-1. The laboratory-scale values of K can be regarded as ideal from which to compare the performance of the industrial unit.


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Research Contributions