Drvna industrija, Vol. 63 No. 3, 2012.
Original scientific paper
https://doi.org/10.5552/drind.2012.1201
Drying Kinetics of Poplar (Populus Deltoides) Wood Particles by a Convective Thin Layer Dryer
Hamid Zarea Hosseinabadi
; Department of Wood and Paper Sciences and Technology, Faculty of Natural Resources, University of Tehran, Karaj, Iran
Kazem Doosthoseini
; Department of Wood and Paper Sciences and Technology, Faculty of Natural Resources, University of Tehran, Karaj, Iran
Mohammad Layeghi
; Department of Wood and Paper Sciences and Technology, Faculty of Natural Resources, University of Tehran, Karaj, Iran
Abstract
Drying of poplar wood (Populus Deltoides) particles was carried out at different drying conditions using a laboratory convective thin layer dryer. Drying curves were plotted and in order to analyze the drying behavior, the curves were fi tted to different semi-theoretical drying kinetics models. The effective moisture diffusivity was also determined from the integrated Fick’s second law equation and correlated with temperature using an Arrhenius- type model to calculate activation energy of diffusion. The results showed that Midilli et al. model was found to satisfactorily describe the drying characteristics of poplar wood particles dried at all temperatures and air flow velocities. In general, the drying rate increases with increasing air temperature and air fl ow velocity. A short constant drying rate period was observed and drying frequently took place at falling rate period in all cases. The effective moisture diffusivity of poplar wood particles increased from 1.01E-10 to 2.53E-10 m2·s-1 as the drying air temperature increased from 65 to 85 °C. The activation energy of diffusion for 1 m·s-1 and 1.5 m·s-1 air flow velocities were calculated as 27.8 kJ·mol-1 and 50.8 kJ·mol-1, respectively.
Keywords
Poplar wood particles; thin layer dryer; drying kinetics model; effective moisture diffusivity; activation energy
Hrčak ID:
86980
URI
Publication date:
27.9.2012.
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