流化床结晶器内氯化钠晶体的磨损过程

结晶器中晶体磨损会导致产品质量下降,造成一系列环境问题.在流化床结晶器(FBC)中,对氯化钠晶体的磨损特性进行研究,利用磨损动力学模型研究磨损时间、循环流量和晶体磨损倾向性对磨碎现象的影响.实验结果表明,流化床结晶器中颗粒的磨损是由表面磨损引起的,且颗粒的磨损过程与颗粒的物理特性和流化条件密切相关.目前广泛使用的Gwyn模型不能准确地描述颗粒物性与磨损之间的关系.为此,提出一种新的颗粒磨损动力学模型,结合颗粒的材料特性来描述晶体磨损过程.通过实验对比研究,新模型的预测更符合晶体真实磨碎现象.

Attrition Process of Sodium Chloride in Fluidized Bed Crystallizer

The particle attrition could degrade product quality in crystallizer, and cause environmental problems. We use attrition kinetics model to research the effect of attrition time, circulation flow rate and particle attrition propensity by researching the crystal attrition characteristic of sodium chloride in fluidized bed crystallizer (FBC). The results show that surface attrition causes particle attrition in FBC and the attrition process of particles is closely related to the physical properties of particles and fluidization conditions. At present, the widely used Gwyn model cannot accurately describe the relationship between particulate property and attrition, proposes a novel particle attrition kinetics model, which describes the crystal attrition process by material properties of particles. The model parameters have definite meanings and are highly correlated with the material mechanical properties of particle, the predictions of this new model are in better agreement with the Gwyn''s model.