论文部分内容阅读
通过对物料在升华干燥过程中的损失分析, 建立了升华干燥过程的损失分析模型。结合升华干燥动力学模型和损失分析模型,以牛肉为冷冻干燥过程的模型物料,计算了物料表面加热温度、干燥室压力和物料厚度等操作条件的变化对升华干燥过程损失的影响。计算结果表明:随着干燥室压力的增大,物料的损失减小;随着物料表面加热温度的降低,损失减小;随着物料厚度的减小,损失逐渐减小;在冷冻干燥过程中,损失主要集中在升华干燥阶段,在解析干燥阶段,物料表面加热温度的升高不会引起损失的大幅度增加。
Through the analysis of the material loss in sublimation and drying process, the loss analysis model of sublimation drying process was established. Combining the kinetic model of sublimation drying and the model of loss analysis, the effects of the operating conditions such as the heating temperature of the material, the pressure of the drying chamber and the thickness of the material on the loss of the sublimation drying process are calculated using the beef as the model material of the freeze-drying process. The results show that the loss of material decreases with the increase of pressure in the drying chamber, the loss decreases with the decrease of the heating temperature on the material surface, and the loss decreases with the decrease of the material thickness. In the process of freeze-drying , The loss mainly concentrated in the sublimation drying stage, in the analytical drying stage, the material surface heating temperature will not cause a significant increase in loss.