基于Weibull分布函数的浆板热风干燥特性

Drying Characteristics of Pulpsheet by Hot-air Based on Weibull Distribution

关键词:  浆板  热风干燥  干燥特性  Weibull分布

Key Words:pulpsheet  hot-air drying  drying characteristics  Weibull distribution

摘要:以未漂硫酸盐针叶木浆为干燥对象，研究了热风温度和风速对浆板干燥特性的影响。利用Weibull分布函数对浆板的干燥特性曲线进行了模拟，并建立热风温度、风速与模型中参数（尺度参数α、形状参数β）的定量关系。结果表明，Weibull分布函数可以很好地模拟浆板的热风干燥过程；模型的尺度参数α与热风温度和风速有关，并且随热风温度和风速的升高而降低；模型的形状参数β与热风风速有关，随热风风速的升高而降低；浆板热风干燥过程的估算水分扩散系数在2.116×10^-7~3.251×10^-7 m²/s之间，干燥活化能为14.8 kJ/mol。

Abstract:In this study, the effects of temperature and velocity of hot air on drying characteristics of unbleached softwood pulpsheet were investigated. The drying characteristic curve was modeled with Weibull distribution model. In addition, the quantitative relationships of scale parameter α and shape parameter β of the model with hot air temperature and velocity were established. The research showed that Weibull distribution model was good at modeling the pulpsheet drying process using hot air. It was found that using the scale parameter α was related to the air temperature and velcotiy,and α would decreased as air temperature and velocity raising. While the shape parameter β was mainly affected by air velocity. And the changes of β and velocity of hot air were opposite. The estimated water diffusion coefficient of pulpsheet was in the range from 2.116×10^-7 to 3.251×10^-7 m²/s during the drying, and the average activation energy was 14.8 kJ/mol.