Abstract:

The mother solution after extracting lithium from Salt Lake contains lithium,potassium and magnesium resources. The direct discharge of mother solution leads to waste of resources,on the other hand,it will damage the whole Salt Lake sys-tem.A mother solution recovery method was provided,that is mother solution was concentrated in salt field,then mixed with summer intergranular brine and winter frozen nitrate brine respectively.The mixed brine was further evaporated in salt field,and precipitated sulphur mixed ore is used to produce potassium magnesium fertilizer,the precipitated potassium mixed ore is used to produce potassium chloride,the liquid brine was used as raw brine for lithium carbonate production.Thereby,the re-cycling of the useful resources of useful resources in mother solution was realized,and the entire mixing brine process was analyzed on the phase diagram.All the processes of the method were realized in the salt field with low cost and pollution-free,and it conformed to the green environmental protection and sustainable development conception,which avoided the damage caused by the massive discharge of lithium mother solution to the salt lake system.

Key words: lithium extracted mother solution, mixing brine, potassic-magnesian fertilizer, potassium chloride, lithium carbonate