昆特依盐湖杂卤石矿“焙烧-热浸”溶钾实验研究

Experiment research on K extraction of polyhalite from Kunteyi salt lake by Roasting-Hot Leaching method

以柴达木盆地昆特依盐湖大盐滩矿区杂卤石矿为原料,进行"焙烧-热浸"溶浸实验,研究300~500℃杂卤石矿的焙烧和焙烧产物90℃热水浸钾效果。结果表明:不同温度下焙烧过程中杂卤石质量减少,是由于杂卤石结构遭受破坏而失去两个结构水;温度越高,杂卤石结构破坏越严重,最低的焙烧温度不低于350℃;焙烧产物在90℃热水中热浸钾收率超过95%,较90℃热水溶杂卤石钾收率(31.23%)和常温21℃溶杂卤石钾收率(23.56%)提高了3倍以上;浸取液钾含量和钾收率随焙烧温度增加而增加。

Roasting-Hot Leaching test was made with polyhalite from Dayantan playa,Kunteyi salt lake,Qaidam Basin in Qinghai as raw materials.The roasting of the polyhalite ore at 300~500℃and the K leaching effect of the roasting products by 90℃hot water were studied.During roasting of process at different temperatures,the weight of polyhalite was reduced because of the structure destruction of polyhalite and the loss of two structural waters.With the roasting temperature increased,the degree of structure destruction of polyhalite was more seriously.The lowest roasting temperature was not lower than 350℃.After roasting,the product was leached by 90℃hot water,the results showed that the K yield was over 95%;the K yield was increased more than three times compared with that of polyhalite dissolving in water at 90℃(31.23%)and 21℃(23.56%);the K concentrations of the leaching liquid and K yield increased with the increase of roasting temperature.