Comparative Study of Heat Treated Beech Wood in Hot Water and Steam Mediums

Document Type : Research Paper

Authors

Abstract

Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Heat treatments of beech wood in 2 different mediums (hot water and steam) at 180ºC were compared by physical, mechanical and anatomical properties. Mass loss in hydrothermally treated wood was higher than hygrothermally treated specimens. Mechanical properties (MOR and MOE) were decreased in both mediums, but strength loss was higher for hygrothermal treated samples. Anatomical changes were investigated by means of a light microscopic analysis. Beech was sensitive to collapse of the vessels in both mediums. In treated beech, radial cracks were observed near the rays both in hydro and hygrothermal treatments. Depletion of extractives on the cell walls and deformation of libriform fibers near the vessels were also observed.

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1- Babicki R., Grzeczynski T. and Wroblewska H. 1997: Effect of hydro-thermal treatment of green beech wood on its chemical and physic-mechanical properties, Wood Sci. Technol. 11: 125-131 (1997).
2- Boonstra M. and Tjeerdsma B. 2006: Chemical analysis of heat treated softwoods, Holz als Roh- und werkstoff 64: 204-211.
3- Boonstra M., Rijsdijk J.F., Sander C., Kegel E., Tjeerdsma B., Militz H., Acker J. van and Stevens M. 2006: Microstructural and physical aspects of heat treated wood. Part 2. Hardwoods, Maderas. Ciencia y tecnologia 8(3): 209-217.
4- Burmester A., 1981: Dimensional stabilization of wood. International Research Group on Wood Preservation, Doc. No. IRG/WP 3171.
5- Garrote G., Domínguez H. and Parajó J.C. 1999: Hydrothermal processing of lignocellulosic materials. Holz als Roh- und Werkstoff, 57(3), 191–202.
6- Gonzalez-Pena MM., Curling S.F. and Hale M.D.C. 2009: On the effect of heat on the chemical composition and dimensions of thermally modified wood. Polymer Degradation and Stability. Doi: 10.1016.
7- Hill C., 2006: Wood Modification: Chemical, Thermal and Other Processes, John Wiley & Sons, Ltd. 239p.
8- Kartal S.N., Hwang W.J. and Imamura Y. 2008: Combined effect of boron compounds and heat treatment on wood properties: Chemical and strength properties of wood, Journal of Materials Processing Technology 198: 234-240.
9- Kocaefe D., Chaudhry B., Poncsak S., Bouazara M. and Pichette A. 2007: Thermogravimetric study of high temperature treatment of aspen: effect of treatment parameters on weight loss and mechanical properties. Journal of Materials Science 42(3):355-361. 
10- Korkut S. and Bektas I. 2008: The effects of heat treatment on physical properties of Uludağ fir (Abies bornmuellerinana Mattf.) and Scots pine (Pinus sylvestris L.) wood. Forest Products Journal 58(3): 95-99. 
11- Korkut S., Kök M.S., Sevim Korkut D. and Gürleyen T. 2008: The effects of heat treatment on technological properties in Red-bud maple (Acer trautvetteri Medw.) wood. Bioresource Technology 99(6): 1538–1543.  
12- Kubojima Y., Okano T. and Ohta M. 2000: Bending strength and toughness of heat treated wood, J. Wood Sci 46:8-15.
13- Mburu F., Dumarcay S., Bocquet JF., Petrissans M. and Gerardin P. 2008: Effect of chemical modification caused by heat treatment on mechanical properties of Grevillea robusta wood. Polymer Degradation and Stability 93: 401-405.
14- McLean JD. 1951: Rate of disintegration of wood under different heating conditions. Proceedings of the American Wood Preservers Association, 47, 155–169.
15- McLean JD. 1954: Effects of heating in water on the strength properties of wood. American Wood Preservers Association Proceeding, 50: 253-80.
16- Mitchell PH. 1988: Irreversible property changes of small loblolly pine specimens heated in air, nitrogen, or oxygen. Wood and Fiber Science; 20(3): 320-55.
17- Mohebby B., Yaghoobi K., Roohnia M., 2007: Acoustic Properties of Hydrothermally Modified Mulberry (Morus alba L.) Wood; European Conference on Wood Modification 2007, 8p.
18- Poncsak S., Kocaefe D., Bouzara M. and Pichette A. 2006: Effect of High Temperature Treatment on the Mechanical Properties of Birch (Betula pendula). Wood Science and Technology 40(8): 647-663.
19- Rusche H. 1973a: Thermal degradation of wood at temperatures up to 200 deg C. I. Strength properties of wood after heat treatment. Holz als Roh- und Werkstoff, 31(7), 273–281.
20- Rusche H. 1973b: Thermal degradation of wood at temperatures up to 200 deg C. Part II. Reaction kinetics of loss of mass during heat treatment of wood. Holz als Roh- und Werkstoff, 31(8), 307–312.
21- Santos JA. 2000: Mechanical behavior of eucalyptus wood modified by heat. Wood Science and Technology 34: 39-43.
22- Seborg R.M., Tarkow H. and Stamm A.J. 1953: Effect of heat upon the dimensional stabilization of wood. Journal of the Forest Products Research Society 3(3): 59–67.
23- Sevim Korkut D., Korkut S., Bekar I., Budakçi M., Dilik T. and Çakicier N. 2008: The effects of heat treatment on physical properties and surface roughness of Turkish Hazel (Corylus colurna L.) wood. International Journal of Molecular Sciences (IJMS) 9(9): 1772-1783.
24- Stamm A.J. 1956: Thermal degradation of wood and cellulose. Industrial and Engineering Chemistry 48(3): 413–417.
25- Sundqvist B., Karlsson O. and Westermark U. 2006: Determination of formic-acid and acetic-acid concentrations formed during hydrothermal treatment of Birch wood and its relation to colour, strength and hardness, Wood Sci Technol 40: 549-561.
26- Taghiyari HR. 2010: Study on the effect of nano-silver impregnation on mechanical properties of heat-treated Poplus nigra, Wood Sci Technol DOI 10.1007/s00226-010-0343-5.
27- Talaei A. and Yaghoobi K. 2009: Physical and mechanical properties of hydrothermally modified mulberry (Morus alba L.) Wood, The International Research Group on Wood Preservation, IRG Document No. IRG/WP 09-40425.
28- Tjeerdsma B.F. and Militz H. 2006: Chemical changes in hydrothermal treated wood: FTIR analysis of combined hydrothermal and dry heat-treated wood, Holz als Roh- und werkstoff, 63: 102-111.
29- Tjeerdsma B.F., Stevens M. and Militz H. 2000: Durability of (hydro)thermal treated wood, The International Research Group on Wood Preservation, IRG Document No. IRG/WP 00-40160.
30- Viitaniemi P. and Jamsa S. 1996: Modification of wood with heat treatment, Espo 1996, VTT Juskaisuja- Publikationer 814.
31- Weiland J.J. and Guyonnet R. 1997: Retifiziertes Holz. 16, Verditchter Holzbau in Europa. Motivation, Erfahrung, Entwicklung. Dreilander Holztagung. 10. Joanneum Research Fachtage. 2-5/11/1997. Grazer Congress. Grazz. Austria.