METHOD OF DRYING WOOD MATERIAL Russian patent published in 2001 - IPC

FIELD: wood-working industry; drying various wood species in form of lumber and wood blanks. SUBSTANCE: according to proposed method, various wood species in form of lumber and/or blanks are loaded into drying chamber and are kept there at atmospheric pressure and high relative humidity of air (about 90%) beginning from temperature of material of 30 C to 55 C during several hours, after which successive alternating stages are performed: heating the material in circulating air medium at atmospheric pressure; material is kept at reduced pressure during period of time at which temperature in center of material reaches the level below boiling point of water at given degree of vacuum. Successive alternating stages are combined in cycles; each cycle includes four and more alternating stages; each cycle is characterized by constant heating temperature at heating stages and by constant relative humidity of air; heating temperature rises fractionally from cycle to cycle and relative humidity of air decreases fractionally from cycle to cycle. EFFECT: high productivity at perfect quality of material. 2 dwg