干冰烟丝膨胀过程的机理研究

Study on the mechanism of dry ice tobacco expansion process

干冰膨胀烟丝(DIET)过程是烟草工业重要的制丝工艺,膨胀后烟丝含水率是表征该工艺的1项重要技术指标。本研究基于卷烟厂制丝车间的实际运行数据,以物料衡算和热量衡算为基础,考虑两相间对流传热系数的变化,并结合适当的工程简化,分别建立了DIET过程中烟丝出口温度、工艺气体回风温度和膨胀后烟丝含水率的数学模型。其中回风温度和膨胀后烟丝含水率数学模型的平均绝对误差分别为0.24%和1.99%,最大绝对误差分别为0.83%和6.33%,该模型可较好地描述工艺条件对二者的影响,对膨胀后烟丝含水率的调控有较好的指导意义。

Dry ice expanded tobacco(DIET)technology is an important process in tobacco industry,and the moisture content of DIET is an important technical index.A mathematical model for tobacco outlet temperature,return air temperature and moisture content of DIET was established based on mass and heat balance and appropriate engineering simplification after considering the change of heat transfer coefficient between two phases.The average absolute percentage errors of the return air temperature and the moisture content are 0.24%and 1.99%,and the maximum absolute percentage errors are 0.83%and 6.33%,respectively.The mathematical model can be used to describe the effect of process conditions and has good guiding significance for moisture content regulation of expanded tobacco.