基于五元体系Na^(+),K^(+),Mg^(2+)// Cl^(-),SO_(4)^(2-)-H_(2)O相图的硫酸钾生产工艺研究及应用  

Research and application of potassium sulfate production process based on Na^(+),K^(+),Mg^(2+)//Cl^(-),SO_4^(2-)-H_(2O) phase diagram of quinary element system

作　　者：盖晓宏 黎国亮 GAI Xiaohong;LI Guoliang(SDIC Xinjiang Luobupo Potash Co.,Ltd.,Hami Xinjiang 839000,China)

机构地区：[1]国投新疆罗布泊钾盐有限责任公司,新疆哈密839000

出　　处：《化工矿物与加工》2024年第11期53-59,共7页Industrial Minerals & Processing

摘　　要：国内外采用硫酸镁转化法生产硫酸钾的工艺一般为两段转化法,其主要理论依据是25℃K^(+),Mg^(2+)//Cl^(-),SO_(4)^(2-)-H_(2)O体系相图。对于硫酸盐型盐湖或利用硫酸盐和氯化钾转化法生产硫酸钾的生产企业,生产原料中会不可避免地存在较多的可溶性杂质,物料为五元体系属性。通常,硫酸钾生产的3个工艺过程(光卤石分解、钾混盐转化、硫酸钾合成),需运用K^(+),Mg^(2+)//Cl^(-)-H_(2)O或K^(+),Mg^(2+),Na^(+)//Cl^(-)-H_(2)O三元、四元简单体系相图和K^(+),Mg^(2+)//Cl^(-),SO_(4)^(2-)-H_(2)O交互四元体系相图指导生产;由于五元体系引入了较多的氯化钠,导致工艺过程与相图存在较大偏差。本文以罗布泊盐湖卤水为研究对象,通过构建五元介稳体系相图,探讨了相图分析的理论依据和相关控制参数。结果表明:Na^(+),K^(+),Mg^(2+)//Cl^(-),SO_(4)^(2-)-H_(2)O五元体系介稳相图可以解释成矿机理,反映生产过程,并确定钾混盐转化温度控制在28℃较为适宜;通过计算还可获得工艺参数,具有便利、统一的优点。The process of producing potassium sulfate by magnesium sulfate conversion method at home and abroad is generally two-stage conversion method.The main theoretical basis is the phase diagram of K^(+),Mg^(2+)//Cl~-,SO_4^(2-)-H_(2O)system at 25℃.For sulfate-type salt lakes or production enterprises that use sulfate and potassium chloride conversion methods to produce potassium sulfate,there will inevitably be more soluble impurities in the raw materials.The materials are five-element system properties.In the past,the three processes of potassium sulfate production(carnallite decomposition,potassium mixed salt conversion,potassium sulfate synthesis),it is necessary to use K^(+),Mg^(2+)//Cl~--H_(2O)or K^(+),Mg^(2+),Na^(+)//Cl~--H_(2O)ternary and quaternary simple system phase diagrams and K^(+),Mg^(2+)//Cl~-,SO_4^(2-)-H_(2O)interactive quaternary system to guide production.Due to the introduction of more sodium chloride in the quinary system,there is a large deviation between the process and the phase diagram.In this paper,the Lop Nur salt lake brine was taken as the research object.By constructing the phase diagram of the five-element metastable system,the theoretical basis and related control parameters of the phase diagram analysis were discussed.The results show that the metastable phase diagram of Na^(+),K^(+),Mg^(2+)//Cl~-,SO_4^(2-)-H_(2O)five-element system can explain the metallogenic mechanism,reflect the production process,and determine that the conversion temperature of potassium mixed salt should be controlled at 28℃.By calculation,process parameters can also be obtained,which has the advantages of convenience and uniformity.

关 键 词：水盐体系法 二段转化 五元相图 硫酸钾 氯化钾 相图 硫酸镁 

分 类 号：TQ132.2[化学工程—无机化工]