An experimental study on change of gas permeability depending on pore structures in three species (hinoki, Douglas fir, and hemlock) of softwood

Eun-Suk Jang,Chun-Won Kang,Jee-Hoon Yuk

doi:10.1186/s10086-020-01925-9

Eun-Suk Jang, Chun-Won Kang + Show 1 more

Open Access

https://doi.org/10.1186/s10086-020-01925-9

Copy DOI

Abstract

The purpose of this study is to analyze the pore structure for the heartwood, intermediate wood, and sapwood sections in three species of softwood (hinoki, Douglas fir, and hemlock) and to investigate the correlation of gas permeability depending on pore structure. For this study, gas permeability and pore size were measured by capillary flow porometry, and classification of a novel method was performed to determine the type of pores (through pores, blind pores, and closed pores) based on International Union of Pure and Applied Chemistry (IUPAC). Gas permeability, through pore porosity, and pore size increased from heartwood to sapwood. The results of multiple regression analysis showed that through pore porosity, mean pore size, and bulk density were significant factors affecting gas permeability.

Highlights

The permeability of wood greatly influences drying rate because free water moves to the surface layer by capillary flow at the beginning of drying [1]
The results showed that pore size and through pore porosity increased from heartwood to sapwood [37]
The cylindrical specimens were dried at 40 °C using a dryer for 1 week and controlled within a 10% moisture content (MC) to exclude the influence of MC between heartwood and sapwood to focus on pore structure

Summary

Introduction

The permeability of wood greatly influences drying rate because free water moves to the surface layer by capillary flow at the beginning of drying [1]. Permeability of wood is recognized as an important parameter in various applications such as heat-treated wood [3,4,5], nanomaterial impregnation [6,7,8] and use of the transverse surface of wood as a porous sound-absorbing material [9,10,11]. Impregnation of aqueous metal nanoparticles into heat-treated solid woods can improve its permeability because some of the wood’s extractives dissolve, producing perforations and pits [14]. Improving the permeability of wood has the advantages of drying defects, impregnation of chemicals, and sound absorption performance [3, 10, 11, 13, 16, 17]

Objectives

Methods

Results

Conclusion