摘要
以白橡锯材为研究对象,采用热压机对其进行热压干燥处理,系统研究了热压温度、热压压力和试件宽度等因素对白橡木材干燥特性、颜色、吸湿性和尺寸稳定性的影响规律,获得了优化的热压干燥工艺。研究结果表明:采用热压干燥法可以实现白橡木的快速高效干燥,随着热压温度的升高,木材干燥速度显著加快,颜色逐渐加深,热压压力和试件宽度对干燥速率和颜色的影响不明显;热压干燥可以显著减小白橡木材的平衡含水率(EMC)和湿胀率,提高其尺寸稳定性,且随着热压温度的升高,白橡木材EMC和湿胀率降低,热压压力和试件宽度对木材EMC和湿胀率无明显影响;与对照材相比,热压干燥白橡木材的EMC降低9.97%~33.67%,径向和弦向湿胀率分别降低8.54%~33.96%、11.26%~30.02%;白橡木材的优化热压干燥条件为:热压温度为140~150℃热压压力为0.1 MPa,板材宽度为自然宽。
Effects of varying press temperatures, pressures and cutting widths on the drying characteristics, color, moisture absorption, and dimensional stability of press dried white oak boards were studied by hot pressing drying and the optimum hot pressing drying process was obtained. The results show that hot pressing drying can fast and effectively dry the white oak, with the increase of the press temperature, the drying rate of wood is significantly accelerated, the color gradually deepens. The effects of press pressure and specimen width on drying speed and color are not obvious. The equilibrium moisture content （EMC） and swelling of white oak lumber can be significantly reduced by hot pressing drying; the dimensional stability can be enhanced. With the increase of hot pressing temperature, the EMC and swelling efficacy decrease. The effects of press pressure and specimen width on EMC and swelling efficacy are not obvious. In this study, compared with the undried cuttings, the EMC, radial and tangential volume swelling of the wood after hot press drying can be decreased by about 9.97%-33.67%, 8.54%-33.96%,11.26%-30.02%, respectively. The optimized conditions of hot pressing drying of white oak boards are as follows： a temperature of 140-150 ℃,a pressure of 0.1 MPa and an original board width.
出处
《林产工业》
北大核心
2018年第2期44-48,共5页
China Forest Products Industry
基金
压干法处理实木地热地板技术研究(ZSYF216-05)
关键词
热压干燥
白橡木
干燥缺陷
色差
尺寸稳定性
Hot press drying
Quercus robur lumber
Drying defects
Color difference
Dimensional stability
