精对苯二甲酸干燥动力学模型

A kinetic model for drying process of pure terephthalic acid

分析了精对苯二甲酸(PTA)干燥过程中干燥温度,物料初始含湿量,空气流速对干燥速率的影响。结果表明:PTA干燥过程由预热阶段、恒速阶段和降速阶段组成,临界含湿量为5%。随着干燥温度或初始含湿量的升高,干燥速率升高,随着载气流量的升高,干燥速率变化不明显。干燥温度对干燥速率的影响最为显著。通过模型比较得出合适的PTA干燥模型为Page模型,模型计算值与实验值吻合较好。

The effects of drying temperature, feedstocks＇ initial moisture content and air velocity on drying rate were analyzed during PTA drying course. The results showed that PTA drying process comprised preheating stage, constant-rate stage and falling-rate stage. The critical moisture content was 5%. The drying rate was increased while increasing drying temperature or initial moisture content. The drying rate had no remarkable change while increasing air flow. The drying temperature had the most profound effect on drying rate. Page model was decided as the most appropriate PTA drying model by comparison. The model calculated data coincided with the experimental data well.