Effect of steam explosion treatment on impregnation of three species of softwoods: North American spruce, Korean pine, and Japanese larch

Abstract

Effects of steam explosion were investigated relative to impregnation of wood. Three types of softwoods [North American spruce (Picea orientalis), Korean pine (Pinus koraiensis), and Japanese larch (Larix kaempferi)] were prepared and subjected to steam explosion treatment. The cross-sectional surfaces of the samples were observed with SEM, and their open-pore and closed-pore porosities were determined using a gas pycnometer. The softwoods were vacuum impregnated using ACQ-2 (Alkaline Copper Quaternary), a commercial preservative. After steam explosion treatment, the impregnation amount increased by 42.9% in the spruce and 155% in the Korean pine. However, there was no significant difference in the Japanese larch. The results from this study indicated that the steam explosion treatment helped to improve open-pore porosity by generating micro-cracks in the cell walls of softwoods, which improved the impregnation process. However, the degree of improvement in impregnation process differed by the species type.

The Optimal Impregnation Amounts of Flame-Retardant for Korean Larch and Japanese Cedar Building Materials

“…The vacuum pressure impregnation process can be optimized by adjusting the flow characteristics of the chemical, chamber temperature, and impregnation pressure and time. Jang and Kang [21] reported that, among various variables in the vacuum pressure impregnation process, pressure was a significant variable in improving the impregnation of wood.…”