Philippine Science Letters
vol. 6 | no. 2 | 2013
published online November 22, 2013


A Mathematical Model for the Drying Characteristics of Microalgae (Tetraselmis sp.)

by Alvin B. Culaba1,4*, Raymond R. Tan2,4, Jose Bienvenido Manuel M. Biona1,4, Aristotle T. Ubando1,4, Neil Stephen A. Lopez1,4, Joel Q. Tanchuco3, Soledad S. Garibay5, Nieves A. Toledo5, Caridad N. Jimenez5, Ida G. Pahila5 and Letty S. Ami5

1Mechanical Engineering Department, De La Salle University, Philippines
2Chemical Engineering Department, De La Salle University, Philippines
3School of Economics, De La Salle University, Philippines
4Center for Engineering and Sustainable Development Research (CESDR),
  De La Salle University, Philippines
5Institute of Aquaculture, College of Fisheries and Ocean Sciences/Division of Chemistry,
  College of Arts and Sciences, University of the Philippines – Visayas, Philippines



Microalgae are some of the most promising sources of biofuel, but their high initial moisture content remains a hindrance to efficient lipid extraction. A major concern that affects the economic feasibility of microalgal biofuel is the drying process. An experimental drying setup was used to analyze the drying characteristics of Tetraselmis sp. The drying characteristic of the microalgae was assessed through radiation heat intensity, air flow velocity, and convective heat input employing a Taguchi orthogonal array design of experiments. The analysis of variance resulted in a linear regression model relating the effects of the three factors mentioned with the three responses: average chamber temperature, average microalgae slurry surface temperature, and average drying rate. The study developed a mathematical model fitted in Newton’s drying kinetics model. The results showed the effect of varying the values of the three factors, reflected in the drying coefficient k of the derived mathematical model.

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Submitted: December 3, 2012
Revised: April 17, 2013; July 10, 2013
Accepted: July 11, 2013
Published: November 22, 2013
Editor-in-charge: Eduardo A. Padlan