Low VOC drying of lumber and wood panel products. Progress report Number 9 [January 1999]

Results from a multi-year study show that a significant part of the extensive variability observed in oriented strand board (OSB) flake dryer emissions can be traced to physiological effects, and the rest can be attributed to handling and other factors. Low-headspace treatment of lumber was scaled up to the 50 kg level. The amount of turpentine collected was of the same magnitude as that released upon drying lumber. For the process to be economical, the wood must first be brought to about 95 C with steam, and then processed with RF. Attempts to remove VOCs from OSB through low-headspace by placing a curtain over the wood failed because of leaks. A more rigid container will be required. RF-treatment does not alter the gas permeability of lumber