棉秆和桑枝疏解木束干燥特性的研究

Drying characteristics of wood bunch from cotton stalk and mulberry branch

【目的】对棉秆、桑枝疏解木束干燥特性进行分析,获得2种疏解木束干燥的最优工艺,为生物质资源的综合利用提供参考。【方法】以棉秆、桑枝疏解木束为研究对象,采用电热鼓风干燥箱进行试验,在单因素试验结果基础上确定L9(34)正交试验因素水平,研究木束初始干基含水率、气流温度、干燥箱装载率等因素对木束干燥特性的影响,运用极差分析法和方差分析法比较各因素对干燥时间影响的差异,干燥时间以将木束干基含水率降至6%为准,含水率的测定参照国家标准GB/T 1931-2009。【结果】棉秆、桑枝疏解木束的干燥可采用高温快速干燥方式,其中棉秆束的最优干燥工艺参数为初始干基含水率60%、气流温度110℃、干燥箱装载率35%,在此条件下,干燥时间为31min;桑枝木束最优干燥工艺参数为气流温度120℃、初始干基含水率80%、干燥箱装载率45%,在此条件下,干燥时间为65min。【结论】在重组方材生产过程中,对不同的材料需要合理控制干燥条件,以节约成本优化重组方材的生产工艺。

【Objective】This study aimed to analyze the drying properties of wood bunch from cotton stalk and mulberry branch and obtained the optimum drying process to improve its utilization.【Method】The drying process was tested used electric drying oven with forced convection.The influences of main parameters（initial moisture content based on dry weight,air temperature and loading rate）on drying time of wood bunch from cotton stalk and mulberry branch were analyzed by range analysis and variance analysis with L9（34）orthogonal test.The drying process stopped when the moisture content was 6%and the moisture content was determined on the basis of the national standard GB/T 1931-2009.【Result】Cotton stalk based wood bunch and mulberry branch based wood could be quickly dried using high temperature.The best drying process for the cotton stalk based wood bunch was：initial moisture content based on dry weight60%,air temperature 110 ℃ and loading rate 35%.Under this condition,the drying time was 31 min.The best drying conditions for mulberry branch based wood bunch was：air temperature 120 ℃,initial moisture content based on dry weight 80%,and loading rate 45%.Under this condition,the drying time was 65 min.【Conclusion】In the production process,reasonable drying process needs to be controlled for different materials for energy conservation.