Abstract: An improvement in a process for separating waste water from a water insoluble organic liquid which is lighter than water and a water insoluble solid which is heavier than water wherein said waste water, organic liquid and solids are introduced into an introduction zone of a gravity separator, thereafter passed through a separation zone of said separator and a water phase is removed from said separator, which improvement comprises a higher purity of waste water by avoiding diminuation of the temperature of the components in said separation zone below the temperature of the waste water at the entrance of the separator by adjusting the temperature in the introduction zone to prevent flocculation of solids in said separation zone.