Abstract:
In this study, lily was dried as thin-layers in the ranges of 65
85 ℃ of drying temperature in a hot-air dryer.The effect of drying hot-air temperature on the drying kinetics was analyzed.Five different dynamic models were fitted nonlinearly by using the drying test data of lily and the best suitable model was selected by comparing the values of the correlation coefficient ( R
2) , the reduced chi-square ( χ
2) and the root mean square error ( RMSE) .The results showed that drying process of lily scales and sliced lily occurred in the falling rate period, and the moisture transfer was controlled by internal diffusion.The Page model was the best suitable to descript the relationship of lily moisture and drying time by hot-air drying.The effective moisture diffusion coefficient (D
eff) and the activation energy ( Ea) were also obtained by experiments under different conditions, the values of Deffwould increase with the addition of drying temperature, Deffvalues changed from 7.73 to 14.12 × 10
-9m
2/s for shred lily, while Deffvalues changed from 4.12 to 9.49 × 10
-9m
2/s for lily scales within the given temperature range. An Arrhenius relation with Eavalues of 42.42 and 30.37 k J/mol for lily scales and shredded lily expressed the effect of shred on the diffusivity.Shredded lily could short drying time and reduce energy consumption.