ENERGY CONSUMPTION AND MATHEMATICAL MODELING OF MICROWAVE DRYING OF DATE

Hassan, Mona M. A.

doi:10.21608/mjae.2016.98173

ENERGY CONSUMPTION AND MATHEMATICAL MODELING OF MICROWAVE DRYING OF DATE

Document Type : Original Article

Author

Mona M. A. Hassan

Associate Prof. of Agric. Eng., Fac. of Agric., Zagazig Univ., Egypt.

10.21608/mjae.2016.98173

Abstract

In the present research, drying characteristics and energy requirements for microwave drying of date palm were reported for two varieties of date palm, (Hayani and Zagloul). During the experiments, drying was carried out until the final moisture content reached a level of less than 20% (db). The experimental data were fitted to six drying models. The models were compared using reduced chi-square (X²), mean bias error (MBE) and root mean square error (RMSE).They were used to determine the quality of the fit.Page , Modified Page (I) and Linear were the best descriptive models. The effective moisture diffusivity was determined by using Fick’s second law and was observed to lie between 8.6×10⁻⁹ and 5.98×10⁻⁸ m²/s for the date palm samples. The minimum total energy consumption (0.08kWh), the minimum specific energy (5.7 MJ/kgH₂O) and maximum drying efficiency (40%) were computed for drying (Hayani). The maximum total energy consumption (0.14kWh), the minimum drying efficiency (32%) and maximum specific energy (7.15 MJ/kgH₂O) were computed for (Zagloul).

Keywords

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