Method for separating foreign solid particles from a liquid

Claim 1

A method for separating foreign solid particles from a contaminated liquid, comprising the steps of pumping into an enclosed tank having a cover a vehicle liquid of a specific gravity greater than that of the contaminated liquid having the particles, pumping into said tank and on top of the vehicle liquid the contaminated liquid and thereby floating the contaminated liquid on the vehicle liquid to present a layer of the contaminated liquid and allow the foreign solid particles to sink into the vehicle liquid, filling said tank up to said cover with both said liquids to create a pressure in said liquids in said tank, removing the originally contaminated liquid from said tank and controlling the rate of removal by use of a valve while continuously pumping additional contaminated liquid with solid particles into said tank and thereby control the height of the layer of the contaminated liquid in said tank, all of said contaminated liquid is introduced and removed relative to said tank at spaced-apart locations adjacent respective opposite sides of said tank and said layer and adjacent the upper surface of said layer, for flow of the contaminated liquid across said tank and optimum sinking of the particles from the contaminated liquid while in said tank, pumping said vehicle liquid into said tank and removing said vehicle liquid from said tank at spaced-apart locations adjacent respective opposite sides of said tank and opposite from the locations of the introduction and removal of the contaminated liquid relative to said tank, to establish a cross-flow between the two liquids, and consequently flushing the vehicle liquid and the solid particles from said tank while continuously pumping the vehicle liquid into said tank.

Claim 2

A method for separating foreign solid particles from a contaminated liquid, comprising the steps of pumping into an enclosed tank having a cover a vehicle liquid of a specific gravity greater than that of the contaminated liquid having the particles, pumping into said tank and on top of the vehicle liquid the contaminated liquid and thereby floating the contaminated liquid on the vehicle liquid to present a layer of the contaminated liquid and allow the foreign solid particles to sink into the vehicle liquid, filling said tank up to said cover with both said liquids to create a pressure in said liquids in said tank, removing the originally contaminated liquid from said tank and controlling the rate of removal by use of a valve while continuously pumping additional contaminated liquid with solid particles into said tank and thereby control the height of the layer of the contaminated liquid in said tank, all of said contaminated liquid is introduced and removed relative to said tank at spaced-apart locations adjacent respective opposite sides of said tank and said layer and adjacent the upper surface of said layer, for flow of the contaminated liquid across said tank and optimum sinking of the particles from the contaminated liquid while in said tank, pumping said vehicle liquid into said tank and removing said vehicle liquid from said tank at spaced-apart locations adjacent respective opposite sides of said tank and opposite from the locations of the introduction and removal of the contaminated liquid relative to said tank, to establish a cross-flow between the two liquids, and consequently flushing the vehicle liquid and the solid particles from said tank while continuously pumping the vehicle liquid into said tank.