Drying Pine Lumber at Very High Temperatures and Air Velocities
Keywords:High-temperature drying, southern pine, drying energy, moisture content variation
AbstractDry-bulb temperatures and air velocities above those typically found in industrial pine kilns were used to reduce drying time in an experimental kiln. Experimental accelerated schedules employed temperatures of 265 and 300 F and air velocities of 1,200 and 2,000 feet per minute (fpm). Additional charges were dried at a temperature commonly used in industrial kilns (230 F) and at air velocities of either 1,200 or 2,000 fpm. Regression analysis showed that air velocity, dry-bulb temperature, and final moisture content had a significant effect on drying time. For example, drying time at 300 F, 2,000 fpm, was nearly half that at 230 F, 1,200 fpm. In the experimental kiln, rapid drying did not require more heat than slower drying.
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