Difusión del agua en astillas de madera de diez especies de rápido crecimiento en plantaciones en costa rica

In fuel wood sources it is important to know the water diffusion coefficient (D) behavior during the drying process. The main objective of this work is to measure D in woodchips with different sizes for ten species of fast-growth plantations in Costa Rica. It was found that D is positively related to moisture content (MC) and negatively related to green specific gravity (SG) and woodchip length, and finally the type of wood (sapwood or heartwood). In species with both sapwood and heartwood (Gmelina arborea and Tectona grandis) D is higher in heartwood than in sapwood. In species with high MC (>120%), as Acacia mangium, G. arborea and Vochysia guatemalensis longer drying times are found. Woodchips with 10cm in length show slower moisture loss, followed by chips 7cm long and finally 5cm chips. Besides, it was found that G. arborea did not show any relationship between SG and D, nor it showed a definite tendency with chip length.