Internal Pressure Development During Supercritical Fluid Impregnation of Wood
Keywords:Douglas-fir, ponderosa pine, white fir, sweetgum, Pacific silver fir, supercritical fluids, pressure
AbstractSupercritical fluid impregnation has tremendous potential for effectively impregnating a variety of species, but little is known about the pressure response in wood during this process. Pressure response was studied in a number of wood species using specially designed high pressure probes, which allowed in-situ monitoring of the treatment process. Pressure response was relatively rapid in permeable species such as pine, but tended to lag in less permeable species. In some cases, the differences between surface and internal pressure exceeded the material properties of the wood, and crushing or fractures resulted. The results indicate that the rates of pressure application and release can be tailored to control pressure differentials to avoid wood damage.
Acda, M. N. 1995. Supercritical fluid impregnation of wood-based composites. Ph.D. dissertation, Oregon State University, Corvallis, OR. 160 pp.nAcda, M. N., J. J. Morrell, and K. L. Levien, 2001. Supercritical fluid impregnation of selected wood species with tebuconazole. J. Wood Sci. Technol. 35:127-136.nAnderson, M. E. 1998. The effects of supercritical Co2 on the bending properties and treatment defects of four refractory wood species. M.S. Thesis, Oregon State University, Corvallis, OR.nAnderson, M. E. R. J. Leichti, and J. J. Morrell. 2000. The effects of supercritical Co2 on bending properties of four refractory wood species. Forest Prod. J. 50(11/12):85-93.nBergman, O. 1991. Temperature and pressure inside wood during creosote impregnation. The International Research Group on Wood Preservation. Document No. IRG/WP/91-3649. Stockholm, Sweden. 16 pp.nBodig, J., and B. A. Jayne. 1982. Mechanics of wood and wood composites. Van Nostrand and Reinhold Co., New York, NY. 712 pp.nChoong, E. T., F. O. Tesoro, and F. G. Manwiller. 1974. Permeability of twenty-two small diameter hardwoods growing on southern pine sites. Wood Fiber 6(1):91-101.nCobham, P. R. S., and P. Vinden. 1995. Internal pressure monitoring during the treatment of Pinus radiata (D. Don.). The International Research Group on Wood Preservation. Document No. IRG/WP/95-40049. Stockholm, Sweden. 11 pp.nCooper, P. A., T. S. Janezic, U. Srinivasan, and A. Omvidar. 1997. Penetration and distribution of styrene in pressure treated hardwoods. The International Research Group on Wood Preservation. Document No. IRG/WP/97-40094. Stockholm, Sweden. 13 pp.nEly, J. F. 1986. An equation of state model for pure Co2 and Co2 rich mixtures. Proc., Gas Processors Assoc. 65:70-79.nIto, N. T., T. Someya, M. Taniguchi, and H. Inamura. 1984. An antiseptic method for wood. Japanese Patent 59-1013111.nKang, S. M., and J. J. Morrell. 2003. Supercritical fluid impregnation of Douglas-fir heartwood with cyproconazole using temperature induced deposition. The International Research Group on Wood Preservation Document No. IRG/WP/03-40259. Stockholm, Sweden. 8 pp.nKayihan, F. 1992. Method of perfusing a porous workpiece with a chemical composition using cosolvents. U.S. Patent 5,094,892.nKim, G. H., and J. J. Morrell. 2000. In-situ measurement of dimensional changes during supercritical fluid impregnation of white spruce lumber. Wood Fiber Sci. 32(1):29-36.nKim, G. H., S. Kumar, E. Sahle-Demessie, K. L. Levien, and J. J. Morrell. 1997. Bending properties of TCMTB-treated southern pine sapwood using supercritical carbon dioxide impregnation process. The International Research Group on Wood Preservation. Document No. IRG/WP/97-40080. Stockholm, Sweden. 9 pp.nMarkstrom, D. C., and R. A. Hann. 1972. Seasonal variation in wood permeability and stem moisture content of three rocky mountain softwoods. USDA Forest Service Research Note RM-212. USDA, Rocky Mountain Forest and Range Experiment Station. Fort Collins, CO. 6 pp.nMarkwardt, L. J., and T. R. C. Wilson. 1935. Strength and related properties of woods grown in the United States. Technical Bulletin No. 479. USDA, Forest Prod. Lab. Madison, WI. 99 pp.nOrfila, C., and J. P. Hosli. 1985. Pressure development in low permeable woods during the intrusion of air. Proc. Am. Wood Preservers' Assoc. 81:111-124.nPeek, R., and S. T. Goetsch. 1990. Dynamics of pressure change in wood during impregnation. The International Research Group on Wood Preservation. Document No. IRG/WP/90-3615. Stockholm, Sweden. 10 pp.nPerry, R. H., and D. W. Green. 1984. Perry's Chemical Engineer's Handbook. McGraw-Hill, New York, NY.nSahle-Demessie, E. 1994. Deposition of chemicals in semiporous solids using supercritical fluid carriers. Ph.D. dissertation, Oregon State University, Corvallis, OR. 301 pp.nSahle-Demessie, E., A. Hassan, K. L. Levien, S. Kumar, and J. J. Morrell. 1995a. Supercritical carbon dioxide treatment: Effect on permeability of Douglas-fir heartwood. Wood Fiber Sci. 27(3):296-300.nSahle-Demessie, E., K. L. Levien, and J. J. Morrell. 1995b. Impregnation of wood with biocides using supercritical fluid carriers. Pages 415-428 in K. W. Hutchenson and N. R. Foster, eds., Innovations in Supercritical Fluids: Science and Technology. American Chemical Society, Washington, DC.nSchneider, P. F., K. L. Levien, and J. J. Morrell. 2003. Internal pressure measurement techniques and pressure response in wood during treating processes. Wood Fiber Sci. 35:282-292.nSiau, J. F. 1984. Transport processes in wood. Springer-Verlag, New York, NY. 245 pp.nSmith, S. M., J. J. Morrell, E. Sahle-Demessie, and K. L. Levien. 1993a. Supercritical fluid treatment: Effects on bending strength of white spruce heartwood. The International Research Group on Wood Preservation, Document No. IRG/WP/93-20008. Stockholm, Sweden. 6 pp.nSmith, S. M., E. Sahle-Demessie, J. J. Morrell, K. L. Levien, and H. NG. 1993b. Supercritical fluid treatment: Its effect on bending strength and stiffness of ponderosa pine sapwood. Wood Fiber Sci. 25(2):119-123.nTsunoda, K., and M. Muin. 2003. Preservative treatment of wood-based composites with a mixture formulation of IPBC-Silafluofen using supercritical carbon dioxide as carrier gas. International Research Group on Wood Preservation, Document No. IRG/WP/03-40251. Stockholm, Sweden. 8 pp.nTsunoda, K., M. Inoue, T. Yoshimura, and A. Adachi. 1999. Supercritical fluid application to wood preservation: Part 1: Principle of treatment and mechanical properties of treated wood. Pages 24-30. in K. Tsunoda, ed., Supercritical fluid application to high performance treatment of wood and composite materials. Proc. 09770184; November 2-5 1998; the 4th Pacific Rim Bio-Based Composites Symposium, Bogor, Indonesia.nWalters, C. S. 1967. The effect of treating pressure on the mechanical properties of wood: I. Red gum. Proc. Am. Wood-Preservers' Association 63:166-178.nWalters, C. S., and J. A. Wittington. 1970. The effect of treating pressure on preservative absorption and on the mechanical properties of Wood II: Douglas-fir. Proc. American Wood Preservers' Association 66:179-193.n
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.