## versión On-line ISSN 0718-3305

### Ingeniare. Rev. chil. ing. v.15 n.1 Arica abr. 2007

#### http://dx.doi.org/10.4067/S0718-33052007000100008

Ingeniare. Revista chilena de ingeniería, vol. 15 No 1, 2007, pp. 55-64

SIMULACIÓN MATEMÁTICA DEL PROCESO DE SECADO DE LA GRACILARIA CHILENA (GRACILARIA CHILENSIS)

MATHEMATICAL SIMULATION OF DRYING PROCESS OF CHILEAN GRACILARIA (GRACILARIA CHILENSIS)

### Antonio Vega Gálvez1   Cristian Tello Ireland1   Roberto Lemus Mondaca1

1 Departamento de Ingeniería en Alimentos. Universidad de La Serena. Casilla 599. La Serena, Chile, e-mail: avegag@userena.cl

RESUMEN

ABSTRACT

The aim of this research is to study and to model the hot air drying kinetics of Gracialaria algae (Gracilaria chilensis), using a convective drier -designed and built at the Faculty of Engineering of Universidad de La Serena- at five dry bulb temperatures (30, 40, 50, 60 and 70oC) and an air velocity of 2.0 ± 0.2 m.s-1. Three empirical models are used for the mathematic modeling (Newton, Henderson-Pabis & Page). During the experiment, only a falling rate period is observed, hence the Fick's second law equation is used to estimate the effective water diffusivity. The drying process shows final moisture contents between 0.096 g water/g d.b. and 0.061 g water/g d.b. for 30oC and 70oC, respectively. Both diffusivity and kinetic parameters k1, k2 and k3 of the proposed models show dependence on temperature, and when being evaluated by the Arrhenius equation, activation energies of 39.92, 33.85, 33.49 and 33.83 kJ·mol-1 are obtained, respectively. According to the statistical analyses used (r2, SSE, RMSE and X2), the Page model shows the best fit quality on experimental data, thus being considered an excellent tool for the kinetic modeling of industrial drying processing of Gracilaria chilensis and the estimation of drying time at different temperatures, in order to achieve a commercial moisture content to be acceptable abroad.

Keywords: Gracilaria, drying, diffusivity, Arrhenius, Page.

Los autores agradecen a la Dirección de Investigación de la Universidad de La Serena (DIUILS) por el financiamiento otorgado para esta investigación.

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Recibido 8 de agosto de 2006, aceptado 7 de noviembre de 2006

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