超临界CO2流体在木材干燥中的应用

超临界流体是指高于其临界压力和临界温度的流体，CO₂是最常用的超临界流体。超临界CO₂流体干燥法可以有效减少气液界面张力，在有效脱除水分的同时最大限度地减少因毛细管表面张力导致材料微观结构的改变。文中综述了利用超临界CO₂流体干燥木材的工艺，以及超临界CO₂流体对木材渗透性和干燥特性的影响；重点综述了近几年来利用超临界CO₂干燥木材的机理，包括使用流体动力学模型预测干燥过程以及使用核磁共振观察水分和CO₂的传递规律，以期为超临界流体干燥木材提供理论参考。

Application of Supercritical CO2 Fluid to Wood Drying

Supercritical fluid is a special fluid which is above its critical pressure and critical temperatures, and CO₂ is the most commonly used supercritical fluid. The supercritical CO₂ fluid drying method can effectively reduce the gas-liquid interfacial tension, and effectively remove the moisture while minimizing the change of the microstructure of materials caused by the capillary surface tension. This paper reviews the process of drying wood using supercritical CO₂ fluids and the effects of supercritical CO₂ fluids on wood permeability and drying characteristics. The focus is put on the mechanism of drying wood using supercritical CO₂ in recent years, including the use of fluid dynamics models to predict the drying process and the observation of moisture and CO₂ transfer using nuclear magnetic resonance. This study is expected to provide theoretical support for the study of drying wood with supercritical fluid.