含钾砂页岩熔盐热活化提钾试验研究

Experimental Study on Extracting Potassium from Potassium Bearing Sandstone and Shale by Thermal Activation of Molten Salt

对含钾砂页岩进行了矿物组成、嵌布特征及化学成分分析,采用熔盐热活化技术对含钾砂页岩中钾元素进行活化试验研究。结果表明,在反应温度为260℃,反应时间为4 h,石灰与含钾砂页岩质量比为0.9,液固比为4时,熔盐热活化技术可以破坏含钾砂页岩中含钾矿物的晶体结构,实现钾元素高效活化,有效钾活化率为91.33%。反应后的固相主要为水钙铝榴石、硅钙石等,其中含有一定量的枸溶性硅、钾、镁、钙成分,改良后可作为土壤改良剂使用。

The mineral composition,dissemination characteristics and chemical composition of potassium bearing sandstone and shale were analyzed.The activation test of potassium bearing sandstone and shale was carried out by molten salt thermal activation technology.The experimental results show that:when the reaction temperature is 260℃,the reaction time is 4 h,the mass ratio of lime and potassium bearing sandstone and shale is 0.9,and the liquid-solid ratio is 4,the molten salt thermal activation technology can destroy the crystal structure of potassium bearing minerals in the potassium bearing sand shale,and realize the efficient activation of potassium.The effective potassium activation rate is 91.33%.After the reaction,the solid phase is mainly composed of hydrocalc aluminum garnet and silicalcite,which contain a certain amount of restricted soluble silicon,potassium,magnesium and calcium,it can be used as a soil conditioner.