Abstract: An oil/water separator tank having intake, discharge and vent fittings is conditioned for in-situ cleaning of the oil separator plate stacks positioned therein by selective opening of manual valves connected to each of such fittings. When so conditioned by opening of the manual valves, the in-situ cleaning is performed during repeated operational phases under automated control of solenoid operated and motor driven valves through which a plurality of sequential operational steps are performed, consisting of (a) low pressure air injected into an air sparging array within the separator tank, (b) supply of potable water into a mixing tank; (c) mixing of the potable water with the cleaning agent within the mixing tank; (d) introduction of the cleaning agent after the mixing thereof into the separator tank to enhance in-situ cleaning by dispersing the low pressure air from the air sparging array; and (e) drainage of collected waste oil from the separator tank into a waste oil tank.

Abstract: In-situ cleaning of the bilgewater processing plates of stacks within a treatment tank chamber of a 50-gpm oil/water separator is performed by an injected chemical cleaning agent dispersed by diverted flow of pressurized air introduced into the tank chamber below the plate stacks by emergence of air bubbles from plural branches of an air sparging array system positioned in underlying alignment with crest formations on the processing plates. The air sparging array system consists of an upper and lower tank arrays.