萤石法制备氟化氢气体动力学的Fluent模拟研究

Gas Dynamics Simulation of the Preparation of Hydrogen Fluoride Using Fluorite Based on Fluent

为探究回转窑萤石-硫酸法制备无水氢氟酸过程中,回转窑内萤石与硫酸间的相互作用及产生的不同气体组分迁移转化规律,基于Fluent软件对氢氟酸(HF)制备过程中窑内气体进行动力学模拟。结果表明,随加热温度升高,萤石与硫酸反应进一步加剧,HF产量随之升高,且聚集在窑尾处,CO_(2)、SiF_(4)杂质气体分别汇聚在窑尾与窑头处。此外,窑内气体平均速度也随温度升高而变快,气体湍流度也随之增加,进一步提高了气体分离难度,而温度对气体径向速度影响较小。因此,在实际生产中应结合HF气体质量分数及分离难度综合选择回转窑的加热温度,从而加强单位时间的产酸效率。

In order to explore the interaction between fluorite and sulfuric acid in rotary kiln during the preparation of anhydrous hydrofluoric acid(HF)by fluorite-sulfuric acid method,and the migration and transformation law of different gas components produced in rotary kiln,the dynamic simulation of gas in the kiln during the preparation of HF was carried out based on Fluent software.The results showed that with the increase of heating temperature,the reaction between fluorite and sulfuric acid further intensified,and the output of HF also increased,and it gathered at the kiln tail.The impurity gas CO_(2) and SiF_(4) gathered at the kiln tail and kiln head,respectively.In addition,the average gas velocity in the kiln also rise with the increase of temperature,and the gas turbulence also increased,further improving the difficulty of gas separation,while temperature had little effect on the radial velocity of the gas.Therefore,in the actual production,the heating temperature of the rotary kiln should be combined with the mass fraction of HF gas and the separation difficulty,so as to strengthen the acid production efficiency per unit time.