Assessment of the drying performance of young <i>Nothofagus alpina</i> under radio frequency vacuum drying

In Chile, sawn timber production is mainly based on plantations of introduced species, whereas native species such as Nothofagus alpina (raulí) show increasing potential under intensive plantation management. Although conventional kiln drying (KD) is the standard process for species requiring extended drying times, radio frequency vacuum drying (RFVD) has demonstrated favorable drying performance in several hardwood species. However, the drying performance of young plantation-grown Nothofagus alpina sawn timber under RFVD conditions was evaluated using KD as a reference. Timber of 28 mm and 55 mm thicknesses was subjected to RFVD and KD drying runs. Drying time, drying rate, final moisture content, drying quality, and transverse shrinkage were evaluated. Under the conditions evaluated RFVD reduced drying time by 56–86% compared with KD while maintaining target moisture content, acceptable drying quality, and low transverse shrinkage values. RFVD also exhibited higher drying rates than KD for both timber thicknesses. The results provide experimental information on the drying behavior of young plantation-grown N. alpina, under RFVD conditions and contribute to the characterization of this material under an alternative drying technology.