Fluid Flow of Polar and Less Polar Liquids through Modified Poplar Wood

Forests

AntoniosN. Papadopoulos¹  Holger Militz²  HamidR. Taghiyari³  Hanieh Abbasi³ 

[1] Laboratory of Wood Chemistry and Technology, Department of Forestry and Natural Environment, International Hellenic University, GR-66100 Drama, Greece;Wood Biology and Wood Products, Georg-August-University Göttingen, 37077 Göttingen, Germany;Wood Science and Technology Department, Faculty of Materials Engineering & New Technologies, Shahid Rajaee Teacher Training University, Tehran 16788-15811, Iran;

关键词: permeation;    porous media;    solid wood;    liquid and gas permeability;    thermal modification;   

DOI  :  10.3390/f12040482

来源: DOAJ

【 摘 要 】

Fast-growing species often have a low natural durability and can easily be attacked by fungi and insects, and therefore it is often better to preserve them before use. Permeability is a physical property in porous media that significantly affects the penetration of water- and oil-based preservatives into the texture of wood. In the present study, the specific gas permeability and liquid permeability to water and kerosene in poplar wood (Populus nigra var. betulifolia) were measured. The poplar trees were grown in plots with two spacings of 3 × 4 m and 3 × 8 m. Separate sets of specimens were also thermally modified in order to examinethe effects of this modification on gas and liquid permeability values. The results showed higher gas permeability in specimens grown in the plot with wider spacing (3 × 8 m), which was attributed to their larger vessel diameter. Kerosene demonstrated significantly higher permeability in comparison to water. This was attributed to the polar nature of water molecules, which tend to make stronger bonds with wood cell-wall polymers, ultimately delaying the movement of water through vessel elements. Thermal modification had an increasing effect on specific gas permeability. The increase was attributed to cracks that occur in the pits and wood cell wall during thermal modification, making way for the easier flow of fluids. Decreased wettability caused by thermal modification resulted in a significant increase in both water and kerosene permeability values.

【 授权许可】

Unknown