白蜡木方材高频真空干燥技术的研究

Study of the Technology of Radio-Frequency/vacuum Drying for Fraxinus Excelsior L Square Timber

本文探讨了高频真空干燥生产中工艺参数的计算和选取,并以白蜡木方材(Fraxinus excelsior L)为试材进行了干燥试验。结果表明:干燥后木材终含水率、干燥质量满足国标二级用材要求。高频加热升温时间较短,干燥阶段的干燥速率稳定不变,干燥过程结合水的脱水效率几乎不变。整个干燥环节用于高频加热的能耗比例较大(67.8%),电能转换效率约为47%,干燥成本为744.9 kW/m^3。干燥的实施要根据木材尺寸、干燥特性及高频设备自身的因素进行干燥参数的选择和计算。

In this study, to solve the industrial production problem on drying technology and schedule establishment, the drying technology such as parameters calculation method and selection rules were discussed and analyzed, as well hardwood square timber（Fraxinus excelsior L） RF/V drying test were carried out according to the calculated parameters for comparison. The results indicated that there were no cracks on the ends, surface and inner of lumbers, the MC was even for all size materials and the wood quality after R/FV drying can meet the grade 2 of GB/T 6491-2012. The heating phrase is shorter and the drying rete is almost same during the drying phrase. The dehydration efficiency of bound water is stable.The energy cost of RF accounts for 67.8% and the power conversion efficiency during the whole process is 47% around, the drying cost is 744.9 kW/m^3. The parameters calculation and selection of drying schedules should be based on the timber size,wood character and equipment.