摘要
采用红外水分分析仪研究了干燥温度在80-230℃范围内紫花苜蓿的干燥过程,分析了不同干燥因素对其茎、叶和茎叶相连情况的干燥速率的影响以及干燥前后茎、叶的收缩率。在自制的压扁实验台上进行了苜蓿茎的压扁实验,对不同压扁度茎的水分损失和干燥特性进行了对比实验。结果表明,苜蓿茎、叶以及茎叶相连部分具有不同的干燥特性。干燥温度是影响苜蓿茎、叶干燥速率的重要因素。苜蓿叶的干燥速率是茎的4—5倍。干燥温度每升高10℃,苜蓿叶的干燥速率增加40%-61%,苜蓿茎的干燥速率增加31%-72%。干燥温度对苜蓿叶的干燥速率的影响大于对苜蓿茎干燥速率的影响;干燥温度对直径较大的苜蓿茎和压扁度较小的苜蓿耋的干燥速率影响较大。苜蓿茎的直径每增大1毫米干燥速率减小23%-27%。当苜蓿茎的长度小于100毫米时,越短的茎的干燥速度越快。干燥过程中叶短轴的收缩率最大。干燥温度100℃和80℃时,压扁度为1.5苜蓿茎的干燥速率与叶的干燥速率接近干燥温度100℃时,长度50毫米的茎与六片叶子相连时干燥速率和叶的干燥速率很接近,这对于减少干燥过程中叶的脱落和营养损失具有重要的参考价值。还给出了压扁度的定义以及牧草压扁压强与压扁度之间的对应计算方法。
230℃ and velocity ; crushing ratio; experiment ; grazing Electronic moisture analyzer is used to study the dehydration of alfalfa during drying temperature 80 - analyze other factors which influence on drying velocity of stems, leaves and stems with leaves attached and the shrinkage of stems and leaves. A system is made for experiments on crushing stems, the moisture loss and the drying property with the different crushing ratio. The result is that stems, leaves and stems with leaves attached have the different drying characteristic. Drying temperature is first factor that influences on drying velocity of alfalfa stems and leaves. Drying velocity of alfalfa leaves is 4 ～ 5 times faster that that of alfalfa stems. When drying temperature is higher than 10 ℃ ,drying velocity of alfalfa leaves will be faster 40% -61% and that of alfalfa stems will be faster 31% ～72%. Drying temperature influences on drying velocity of alfalfa leaves more than on that of alfalfa stems ; drying temperature influences more on alfalfa stems with larger diameter and less crushing ratio. When diameter is larger for each 1 millimeter, drying velocity of alfalfa stems will be slower 23% ～ 27%. When the length of alfalfa stems is less than 100 millimeter,the shorter alfalfa stems are ,the faster drying velocity will be. The shrinkage of minor dimension of alfalfa leaves is most in the process. Under drying temperature 100℃ and 80 ℃ ,drying velocity of crushing ratio 1.5 alfalfa stems is close to that of alfalfa leaves, under drying temperature 100 ℃ ,drying velocity of stems 50 millimeter long with six leaves attached is clse to that of alfalfa leaves, which are meaningful to make leaves falling and nutrition loss les in the dehydration. This text also presents the definition of crushing ratio as well as a method to calculate between the intense of pressure on grazing and the crushing ratio.
出处
《河北理工学院学报》
2006年第2期128-134,共7页
Journal of Hebei Institute of Technology
关键词
苜蓿
干燥
干燥速率
压扁度
实验
牧草
alfalfa
dehydration
drying velocity
crushing ratio
experiment
grazing
