马铃薯吸附干燥特性及模型拟合

Potato′s adsorption drying characteristic and model regressing

在实验的基础上研究了马铃薯的干燥特性,考察了温度、湿度、风速和粒子大小对马铃薯的干燥特性的影响。对马铃薯的干燥特性进行模型拟合结果表明:马铃薯吸附式低温干燥过程分为调整、恒速和降速3个阶段。含水率从76.88%变化到65.44%这段为调整阶段;从65.44%变化到47.34%这段为恒速阶段,主要是去除非结合水;从47.34%降到27.7%为降速阶段,主要脱除非结合水及部分结合水,干燥速度下降。温度是影响干燥的主要因素,温度越高,湿度越小,介质流速快,干燥速度越快。Page模型能够较好地拟合马铃薯干燥过程的特性。

The drying characteristic of potato was studied based on experiments, and the effects of temperature, humidity,velocity of drying medium and the particle size of potato on drying process were investigated. The resuits presented that potato＇s low temperature adsorption drying process was divided into three stages： adjustment stage, constant speed stage and speed reduction stage. The section when the water ratio was between 76.88% and 65.44% was considered as adjustment stage. Water ratio of constant rate stage was from 65.44% to 47.34% ,and non-conjoint water was mainly removed in this section. The section that the water ratio range was from 47.34% to 27.7% was called descending stage,and non-bond water and part of bond water was mainly removed and the drying rate fell down in this stage. Temperature was the main influencing factor. The higher the temperature was, the lower the relative humidity was, and the faster the drying rate was. Page model can preferably fit the characteristic of potato drying process.