Abstract: Waste water, in the form of an oil-water mixture, is passed through a series of successive processing stages for effectively separating the water from the oil and directing the same into respective storage compartments. The separated water is conditioned in its storage compartment for reuse by providing a circulating pump therein for circulating and agitating the separated water and thereby aerating the same to prevent stagnation and freezing of the stored separated water. Further, an additional pump is provided in the water storage compartment for directing the separated water from the storage compartment to a desired location for reuse. The separated water may be heated selectively as it is directed away from the water storage compartment, and fresh water also may be introduced into the water storage compartment if the separated water therein drops to a predetermined lower level.

Abstract: A plurality of compartments are provided, including intercommunicating first and second oil-water separation compartments, each provided with respective drains therein and wherein the flow of water from the first to the second compartment is restricted so as to increase the residence time of the water in the first compartment for increasing the separation of oil therein. The mouth of the drain in the first compartment is positioned higher than the mouth of the drain in the second compartment and so located as to be above the surface of the water when the first compartment is substantially filled with water so as to accommodate a layer of oil floating on the surface of the water so that only oil will flow into the drain and thus be removed from the water virtually free of any water mixed therewith.