Abstract: An apparatus separates grease from a waste effluent containing a grease and water mixture prior to disposing of the effluent in a sanitary sewage system. A separator tank receives and holds the effluent while the mixture separates into an upper grease fraction and a lower water fraction. A means is provided for introducing the effluent into the tank either periodically or directly from the source of the effluent. A withdrawal means is associated with the tank for withdrawing at least a portion of the water fraction from the tank means when the effluent in the tank means reaches a first predetermined level. The withdrawal means stop withdrawing the water fraction from the separator tank when the effluent in the tank reaches a second predetermined level lower than the first predetermined level. The grease can be stored in th separator tank itself or can be transferred to a separate storage tank.