MATHEMATICAL MODELING AND EFFECTIVE DIFFUSION OF JATROPHA (Jatropha curcas L.) SEEDS DURING DRYING

作者：Resende Osvaldo^*; Ullmann Renan; Siqueira Valdiney C; Chaves Tarcisio H; Ferreira Lenio U

来源：Engenharia Agricola, 2011, 31(6): 1123-1135.

• drying curves
• mathematical models
• activation energy

The aim of this study was to adjust different mathematical models to experimental data for jatropha seed drying (Jatropha curcas L.) and determine the effective diffusion coefficient and obtain the activation energy for the temperature range used. Jatropha seeds harvested with moisture content of 0.67 (decimal d.b.) and dried in a natural environment to reduce and homogenize the moisture content for 0.30 (decimal d.b.). Jatropha drying was performed in experimental drier maintained at controlled temperatures of 30; 40; 50; 60 or 70 +/- 1 degrees C and relative humidity of 55.98; 41.44; 35.35; 26.21 and 13.37 +/- 3%, respectively. Experimental data were fitted to eleven mathematical models used to represent the process of drying of agricultural products. It was concluded that among the models tested, Page and Henderson and Modified Pabis presented the best fitting to experimental data, and the Page model selected for describing the drying curves from jatropha because of their simplicity; the effective diffusion coefficient increases with increasing temperature, with magnitudes between 3.93x10(-10) and 9.19x10(-10) m(2) s(-1) for the temperature range 30-70 degrees C, respectively. The activation energy for liquid diffusion during jatropha drying was 15.781 kJ mol(-1).

• 出版日期2011-12