Abstract
Two models of the vapour boron timber treatment process have been developed. The first model assumes that trimethyl borate and methanol penetrate timber boards by convective fluxes alone. The second model assumes that both convective and diffusive fluxes influence the flow patterns. Initial simulations of the process using these models show that a number of variables affect the boric acid retention profile. Of particular interest are timber moisture content, timber permeability, vessel occupancy, and rate of evaporation of preservative. The model variables of interest will be investigated in Part II of this paper.
Zusammenfassung
Zwei Modelle der Kesseldruck-Imprägnierung mit Borat wurden entwickelt. Das erste beruht auf der Annahme, daß Trimethylborat und Methanol sich nur konvektiv im Holz ausbreiten. Das zweite Modell zieht sowohl konvektive als auch diffusive Strömungen in Betracht. Die ersten Simulationen des Imprägnierungsprozesses aufgrund dieser Modelle machten deutlich, daß eine Reihe von Variabeln das retentionsprofil der Borsäure beeinflussen. Von besonderem Interesse sind dabei die Holzfeuchte, Permeabilität des Holzes, Kesselfüllung und die Verdampfungsrate des Schutzmittels. Die Auswirkung dieser Variabeln innerhalb der Modelle werden im zweiten Teil der Arbeit untersucht.
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John M. Evans gratefully acknowledges the financial and academic support of the New Zealand Forest Research Institute Ltd, to carry out the work described in this paper.
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Evans, J.M., Keey, R.B., Walker, J.C.F. et al. The modelling of the vapour boron treatment ofPinus radiata D. Don. Holz als Roh- und Werkstoff 55, 45–49 (1997). https://doi.org/10.1007/s001070050223
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DOI: https://doi.org/10.1007/s001070050223