三水磷酸氢二钾不同结晶工艺下产品中微量元素的变化研究

Study on The Changes of Trace Elements in The Product of Different Crystallization Process

采用间歇实验法研究了不同搅拌速率、pH、降温方式、料浆浓度、不同结晶终点温度等结晶工艺条件下三水磷酸氢二钾产品中微量元素的变化情况。研究表明:经结晶处理产品中钠镁铁铝离子含量大幅降低,钙离子含量也略有降低;对比不同结晶工艺条件,搅拌速率在250~300 r·min^(-1)时,料浆pH等于9.16时,降温速率较慢时,产品中微量元素含量相对较低;料浆浓度对产品中微量元素的影响不显著;结晶终点温度对产品中钙砷元素含量有一定的影响,对其他微量元素含量的影响不显著。

The changes of trace elements in the product of dipotassium hydrogen phosphate trihydrate under different crystallization conditions,such as stirring rate, pH value, cooling means, slurry concentration, the differently crystallization end temperature. Researches showed that： The content of sodium, magnesium, iron and aluminum ion in the crystallization products decreased greatly, and the content of calcium ion decreased slightly; Compared with the different crystallization conditions, the content of trace elements in the product were relatively low, when the stirring speed was 250 r·min^-1-300 r·min^-1, the slurry ptt was equal to 9.16, and the cooling rate was slow; The effect of slurry concentration on the trace elements in the product was not significant; The temperature of the end point of crystallization had some influence on the content of calcium and arsenic in the product, but not on other trace elements.