Method and apparatus for separating oil from aqueous liquids

Claim 3

Apparatus for removing oil from a mixture of oily particles in an aqueous liquid comprising, a separator having a mixture inlet chamber at the lower end positioned beneath a foraminous support, a mass of oleophilic granules having a specific gravity greater than water resting on said foraminous support under no-flow conditions, said mass of granules being upwardly unconfined so that said mixture can flow upwardly through said foraminous support and then through said mass of granules with a velocity adequate to lift said granules individually and free from mutual support into a contact zone above the foraminous support in which the granules contact the oily particles in the mixture to collect and coalesce oil from said mixture and then release the oil in the form of visible droplets back into the rising non-turbulent mixture column, a steeply inclined screen located above said contact zone in the path of the upwardly moving liquid leaving said contact zone, said screen removing the droplets of oil from said mixture, the upper portion of said inclined screen communicating via a continuous solid oleophilic path with an oil storage chamber positioned above the screen so that oil removed by said screen will flow to storage and oil outlet means, and outlet means for removing clarified water which has passed through said screen.

Claim 4

Apparatus for removing oil from a mixture of oily particles in an aqueous liquid comprising, a separator having a mixture inlet chamber at the lower end positioned beneath a foraminous support, a mass of oleophilic granules having a specific gravity greater than water resting on said foraminous support under no-flow conditions, said mass of granules being upwardly unconfined so that said mixture can flow upwardly through said foraminous support and then through said mass of granules with a velocity adequate to lift said granules individually and free from mutual support into a contact zone above the foraminous support in which the granules contact the oily particles in the mixture to collect and coalesce oil from said mixture and then release the oil in the form of visible droplets back into the rising non-turbulent mixture column, a steeply inclined screen located above said contact zone in the path of the upwardly moving liquid leaving said contact zone, said screen removing the droplets of oil from said mixture, the upper portion of said inclined screen communicating via a continuous solid oleophilic path with an oil storage chamber positioned above the screen so that oil removed by said screen will flow to storage and oil outlet means, and outlet means for removing clarified water which has passed through said screen.

Claim 5

Apparatus as recited in claim 2 in which said inclined screen is inclined at an angle of at least about 75° to the horizontal.

Claim 6

Apparatus as recited in claim 2 in which said oleophilic granules have a specific gravity of from approximately 2.0 to approximately 3.5.

Claim 7

Apparatus as recited in claim 2 in which the distance from the top of said mass of granules, when said granules are at rest, to the bottom of said screen is at least 20 inches.

Claim 8

Apparatus as recited in claim 2 in which the distance from the top of said mass of granules, when said granules are at rest, to the bottom of said screen is at least 30 inches.

Claim 9

Apparatus as recited in claim 2 in which said separator is cylindrical and said inclined screen is a conical screen communicating at its upper periphery with the interior of said cylindrical separator.

Claim 10

Apparatus as recited in claim 7 in which a tube extends into the upper end of said cylindrical separator so that the water passes out of the separator through said tube and the oil is moved along said screen into an annular oil storage chamber between said separator and said tube.

Claim 11

Apparatus as recited in claim 2 in which said separator is rectangular and said inclined screen is a V-shaped screen communicating at its edges with the interior of said rectangular container.

Claim 12

Apparatus as recited in claim 2 in which a plurality of separator units are placed within a common water receptor, said separator units overflowing into said receptor, and said receptor having an outlet means to maintain the water level desired in said separator units.

Claim 13

Apparatus as recited in claim 2 in which an oil-water interface sensor is positioned within the oil storage chamber and communicates with an oil outlet control valve for maintaining the oil-water interface level within the oil storage chamber.