Method for enriching lithium from lithium clay

A method for enriching lithium from a lithium clay, comprising the following steps:

• (1) crushing the lithium clay to produce the −1 mm size fraction, wherein the mass proportion of the −0.15 mm is ≥60%;
• (2) flotating the −1 mm, adding an aqueous solution of ferric sulfate or ferric nitrate, and stirring evenly, then adding regulator to adjust pulp pH value between 9-10, then adding an aqueous solution of sodium oleate and an aqueous solution of cocoamine, stirring evenly, and then flotation to obtain a rough concentrate and a rough tailing;
• (3) flotating the rough concentrate, and adding a pH regulator to adjust a pH value of the system to be 9-10, and stirring evenly, then adding an aqueous solution of sodium oleate and an aqueous solution of cocoamine, stirring evenly, and then flotation to obtain a concentrate A and a cleaned tailing;
• (4) mixing the rough tailing in step (2) with the cleaned tailing in step (3) and performing a wet ball milling to obtain a tailing A with a mass ratio of a −0.074 mm tailing ≥80%;
• (5) flotating the tailing A, adding an aqueous solution of ferric sulfate or ferric nitrate, stirring evenly, adding a pH regulator to adjust a pH value to be 9-10, then adding an aqueous solution of sodium hexametaphosphate, stirring evenly, adding an aqueous solution of sodium oleate and an aqueous solution of cocoamine, stirring evenly, and then flotation to obtain a reground rough concentrate and a reground rough tailing;
• (6) flotating the reground rough concentrate, adding a pH regulator to adjust a pH value to be 9-10, then adding an aqueous solution of sodium hexametaphosphate, stirring evenly, adding an aqueous solution of sodium oleate and an aqueous solution of cocoamine, stirring evenly, and then flotation to obtain a concentrate B;
• (7) flotating the reground rough tailing, adding a pH regulator to adjust a pH value to be 9-10, then adding an aqueous solution of sodium oleate and an aqueous solution of cocoamine, stirring evenly, and then flotation to obtain a cleaned tailing B;
• and
• (8) using the concentrate A and the concentrate B as a final concentrate, and using the cleaned tailing B as a final tailing.