We studied the drying kinetics of wood chips of three domestic wood species, beech, birch and spruce, taking into account two different chips size classes P16 and P31.5. Stationary convective drying of wood chips was carried out in the laboratory drying tunnel at varying temperature between 40 ⁰C and 80 ⁰C, and the air velocity in the range between 1 m/s and 3 m/s. Drying process of 1.5 cm, 3 cm and 5 cm chips layer was monitored gravimetrically, on the basis of which we calculate the time constant, diffusion coefficient in the chips layer and convection mass transfer coefficient. Generally, the fastest drying was at spruce chips, and the slowest was drying of beach chips. Drying rate increased with the raising of temperature and the air velocity, and decreased with thickness of the chips layer. The prevailing external mass transfer resistance was determined at all drying conditions, in all wood species and all size classes of chips. Convection mass transfer coefficient and diffusion coefficient generally increased with increasing of drying temperature and air velocity.
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