地浸采铀碳酸钙结垢主要影响因素研究

Research on main influence factors on calcium carbonate scaling of in-situ leaching process

本文介绍了CO2+O2地浸中结垢的形成机理、危害与主要处理办法,提出了结垢的主要影响因素为钙离子浓度、碳酸氢根浓度和pH值。使用SI饱和指数法预测了某铀矿床地浸采铀过程中结垢的产生过程,并通过化学分析确定了结垢的主要成分为碳酸钙。从理论上提出了适宜的处理措施,即向浸出剂中加入一定浓度的CO2,降低其pH值,改变了结垢产生的化学条件,促使碳酸钙逐渐溶解。现场试验使用后,钻孔的注液量得以恢复,取得了良好的效果。

This paper introduces the hazards of scaling,the causes of formation and the treatment measures.This reaction are controlled by three factors,which are the content of calcium ion,the content of hydrocarbonate and pH value.The SI saturation index method has been applied in predicting the formation of scaling during in-situ leaching field test.It is shown that the main component of the scaling is calcium carbonate through chemical analysis.Adding a certain concentration of CO2 to the lixiviant can depress the pH value and dissolve calcium carbonate scaling.As a result,the volume of injection wells are recovered and good effects are gained.