摘要
以速生马尾松锯材为研究对象,采用常压过热蒸汽对其进行干燥脱脂一体化处理,系统研究了干燥脱脂过程中马尾松木材内部温度及含水率变化规律,讨论了过热蒸汽温度对锯材干燥速率、干燥质量、颜色、表面溢脂及微观构造的影响规律。结果表明:过热蒸汽干燥脱脂过程中,锯材内部温度及含水率变化可分为快速升温加速干燥段、恒温恒速干燥段和升温减速干燥段三个阶段,干燥速率介于0.14~0.26%/min,过热蒸汽温度对干燥速率影响非常显著;过热蒸汽干燥脱脂材可达到锯材干燥质量指标二级以上标准,与常规干燥材相比,发生的表裂缺陷少,140℃时出现内裂缺陷;过热蒸汽干燥脱脂处理对木材颜色的影响不显著;过热蒸汽干燥材表面不发生溢脂,达到一级脱脂松木锯材标准;过热蒸汽干燥处理破坏了树脂道内的薄壁细胞,处理后的树脂道内残存有固态松香。
In this study, superheated steam at atmospheric pressure was used for drying and degreasingmasson pine （Pinus massoniana Lamb.） lumber.The changes of wood internal temperature and moisture content was investigated in the drying process, and the effect of the superheated steam temperature on the drying rate, drying qualities, color, overflow of resin on the surface and micro-structure of the treated wood was discussed. The results showed that： the changes of internal temperature and moisture content of masson pine wood could be divided into three periods in the drying process which were fast heating phase, constant temperature and rate drying phase and slow heating phase,the treatment temperature affected the drying rate significantly, which ranged from 0.14 to 0.26 %/min; the superheated steam drying and degreasing treated lumber achieved the 2 class on standard of lumber drying qualities, compared with the air-dried wood, less surface cracks appeared in the steam treated samples and internal cracks happened when temperature rised to 140 oC; there was little significant effect of superheated steam temperature on wood color, the changes of total aberration ~ E＊ was about 0.87-6.85; there was none overflow resin appeared on the superheated steam treated lumber, which achieved the 1 class on standard of swan lumber deresination pine;lots of parenchyma cells in resin canals were damaged after superheated steam treatment, and reminded solid rosin in the resin canal.
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2017年第6期108-113,共6页
Journal of Central South University of Forestry & Technology
基金
国家林业局948项目(2014-4-50)
林业科学技术国家级推广项目([2015]51号)
关键词
马尾松
锯材
过热蒸汽
干燥
脱脂
Masson pine （Pinus massoniana Lamb.）
swan lumber
superheated steam
drying
degreasing
