在并/逆流喷雾蒸发器中浓缩净化磷酸的研究  

Study on concentration and purification of phosphoric acid in co/counter-current evaporator

作　　者：权晓威[1] 赵淑贤[1] 李富强[1] 刘钟海[1] 

机构地区：[1]四川大学化工学院,四川成都610065

出　　处：《无机盐工业》2010年第2期36-39,共4页Inorganic Chemicals Industry

基　　金：国家科技支撑计划课题<高纯磷化工产品关键设备开发>资助项目(2007BAE58B02)

摘　　要：为获得较高浓度磷酸以满足对磷酸使用和运输的要求,采用正交实验和单因素实验对净化稀磷酸进行了喷雾蒸发浓缩的系统实验研究。实验结果发现:影响净化稀磷酸蒸发浓缩效果的因素由主到次依次为稀磷酸流量、热风进口流量、二次风比例、热风进口温度、喷嘴气液比;浓缩的效果正比于热风进口流量、热风进口温度、稀磷酸流量的倒数,且在喷嘴气液质量比大于0.8时受其影响不大;二次风的引入对稀磷酸浓缩不利。在实验装置上经喷雾浓缩,成功获得了质量分数不低于85%的浓磷酸,并发现相应的热风出口温度不宜低于110℃。由此可见,通过喷雾蒸发浓缩得到较高浓度的磷酸是可行的。Systematically experimental study on spray evaporation to concentrate purified phosphoric acid has been carried out by orthogonal and single factor experiments in order to attain highly concentrated phosphoric acid to achieve the quality requirement of utilization and transport of it. Results showed that the factors influencing evaporation concentration efficiency of dilute purified phosphoric acid, according to the importance of which, were dilute phosphoric acid flow rate,inlet heated air flow rate, ratio of secondary air, inlet heated air temperature, and gas to liquid ratio at atomizer;efficiency of concentration,which was weakly related to gas to liquid ratio at atomizer when it is more than 0.8,was proportional to inlet heated air flow rate,inlet heated air lemperature, and reciprocal of dilute phosphoric acid flow rate;induced secondary air did not facilitate concentration. Besides, concentrated phosphoric acid that was up to 85% in mass fraction of H3PO4 has been obtained in experiment and it was also found that the temperature of relevant outlet gas should not be less than 110 ℃. So it is feasible to concentrate purified phosphoric acid to get comparatively high concentration by spray evaporation.

关 键 词：磷酸 喷雾蒸发 喷嘴气液比 

分 类 号：TQ126.35[化学工程—无机化工]