采用HSC Chemistry 5.0热力学分析软件研究不同气氛和温度条件对华南含砷铁矿石中砷平衡组成及脱砷率的影响,并结合实验进行验证。结果表明:在惰性气氛中,增加Ar及初始As含量能降低体系的O2分压、提高脱砷率;在还原性气氛中,铁矿石脱砷体系气氛需要适宜的CO含量。当CO含量较高时,O2及CO2能削弱体系的强还原性气氛,促进脱砷;当CO含量较低时,O2的存在不利于脱砷,但CO2的影响微弱。不论在何种气氛中,提高温度均有利于脱砷,实验结果与热力学分析结果基本吻合。在氧化性气氛或强还原性气氛中,由于受动力学条件的限制,仍能获得一定的脱砷率。
The effects of different atmosphere and temperature conditions on the equilibrium species and arsenic removal about arsenic-bearing ores from South of China were investigated by HSC Chemistry 5.0 thermodynamic analysis software.And some experiments were made to verify the thermodynamic analysis data.The results show that the increase of Ar and initial As content can improve arsenic removal due to the decrease of the partial pressure of O2.In the reducing atmosphere,arsenic removal requires an appropriate CO concentration of the system.When the CO concentration is high in the system,O2 and CO2 promote the arsenic removal by slaking down the strong reducing atmosphere.When the CO concentration is low,O2 has a negative effect on the arsenic removal but the effect of CO2 is feeble.A rise of temperature enhances the arsenic removal in any atmosphere.The experiment results are in good agreement with those of the thermodynamic analysis.But in the oxidizing or strong reducing atmosphere an appropriate arsenic removal can be obtained due to dynamic limit.