Modelling of Drying Curves of Spruce, Beech, Willow and Alder Particles

Drying behaviour of spruce (Picea abies (L.) H. Karst.), beech (Fagus sylvatica L.), willow (Salix alba L.), and alder (Alnus glutinosa (L.) Gaertn.) particles was investigated in a convective dryer at constant air velocity of 0.01 m/s and at the drying air temperature of 25, 60, 80, and 150 °C. The results of the experiments have shown that the wood species and drying air temperature infl uence the drying behaviour. The experimental drying data of wood particles obtained were fitted to six empirical models. The effects of wood species and drying air temperature on the drying model parameters were determined. The accuracy of the models was measured using the determination coefficient (R2), root mean square error (RMSE), and reduced chi–square (χ2). The results showed that Lewis model, Henderson and Pabis model, and modifi ed Page model, with the model parameters determined taking into account the effect of wood species and of drying air temperature, were found to satisfactorily describe the drying curves of spruce, beech, willow, and alder particles.