METHOD FOR COMBINED DRYING OF WOOD USING WAVES OF DIFFERENT PHYSICAL NATURE Russian patent published in 2011 - IPC F26B5/02 F26B3/02 F26B3/04 

FIELD: physics.

SUBSTANCE: method involves complete removal of branches and roots from freshly-cut wood, laying the freshly-cut wood without branches and roots into a first pile, storage and first primary drying, loading the logs in a second pile onto a vehicle, transporting the logs to a wood-sawing area and second primary drying, packing the logs on the wood-sawing area into a third pile, storage before sawing and third preliminary drying, removing bark from the logs, sawing the pre-dried logs into sawn wood, packing the sawn wood into a fourth pile and first drying, packing the sawn wood into a sixth pile in a main drying chamber and final drying, unloading the sawn wood and further transportation to the consumer. The top part of the trunk of the freshly-cut wood and moisture accumulated therein during the first preliminary drying is removed directly before transportation. The lower parts of the trunks in the first, second and third piles are raised at least three degrees compared to the top parts of the trunks, which ensures their reliable gripping by the loading device. The logs in the vehicle are packed with their lower parts on the cabin of the vehicle. The sawn wood is packed into a pile taking into account the fibre structure of the wood - lower parts of the wood are on one side of the corresponding pile exposed to acoustic waves, and the top parts of the wood are on the opposite side of the corresponding pile. Lower parts of sawn wood in the fourth pile in the main and additional drying chambers are raised at least three degrees compared to top parts of the sawn wood, which ensures reliable gripping by the loading and unloading apparatus. Roots are removed simultaneously with the cambium and thin layer of the surface of the wood, and also simultaneously with wood accumulated therein during three preliminary drying steps. Further, trunks of the freshly-cut wood without branches and roots in the first pile, logs in the second and third piles, sawn wood in the fourth pile, as well as sawn wood in the fifth and sixth piles - in the main and preliminary drying chambers, respectively, are exposed to acoustic waves at frequency ranging from 2×10¹ Hz to 5×10⁴ Hz with intensity of not less than 100 W/m² from their lower parts to their top parts, as well as from top to bottom on the entire surface area of each pile, which intensifies natural flow of moisture along fibres and under the effect of gravitational force, respectively. Differential frequency of acoustic waves in the preliminary drying chamber corresponds to natural resonance frequency of the preliminary drying chamber, which causes its mechanical vibration, under the effect of which there is more intense removal of moisture from the surface of the sawn wood. Further, during second drying of the sawn wood in the preliminary drying chamber, a portion of drying agent removed from the main drying chamber is used. Further, wood juice is released from the top parts of trunks of freshly-cut wood, branches, as well as roots with cambium and the thin layer of surface of the wood, as well as the wood itself in corresponding acoustic cyclones under the effect of centrifugal forces, acoustic waves. Sawdust and other wood processing wastes which are further dried are taken for related production.

EFFECT: invention shortens duration of the technological process, reduces power consumption during drying per unit volume of wood and improves quality of the wood.

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