METHOD FOR TREATING CLEANING WASTE LIQUID

The present invention relates to a method of treating a cleaning waste liquid which includes a pretreatment step of removing a portion of an organic solvent from a cleaning waste liquid containing a positive electrode active material, a binder, and the organic solvent; a first step of precipitating the binder by adding water to the cleaning waste liquid from which the portion of the organic solvent has been removed; a second step of removing the precipitated binder to obtain a first treatment solution containing the positive electrode active material, the water, and the organic solvent; a third step of separating the positive electrode active material from the first treatment solution to obtain a second treatment solution containing the water and the organic solvent; and a fourth step of removing the water from the second treatment solution and recovering the organic solvent.