Method and apparatus for recovering low density liquids in surface water

A portable skimming apparatus for recovering a light-density liquid on the surface of a body of heavier-density liquid, the apparatus comprising:

• floating hull means defining a first through tunnel having an inlet port and a discharge port, a second tunnel, and a holding tank for containing the collected light-density liquid;
• power means positioned within the first tunnel for drawing subsurface heavier-density liquid through the inlet port of the first tunnel, through the first tunnel and out the discharge port of the first tunnel;
• contour gate means secured to the floating hull means for separating liquids into the first and second tunnels;
• the second tunnel having a light-density liquid/heavier-density liquid inlet port positioned above the inlet port of the first tunnel for receiving light-density liquid and heavier-density liquid into the second tunnel, and having a heavier-density liquid outlet port positioned below the light-density liquid/heavier density liquid inlet port and adjoining the first tunnel between the inlet port of the first tunnel and the power means, the second tunnel defining a heavier-density liquid flow path extending generally downward from its inlet port to its outlet port;
• and
• skimming gate means pivotally secured to the hull and defining in part the second tunnel for passing the light-density liquid floating on the surface of the heavier-density liquid from the second tunnel to the holding tank, such that substantially all light-density liquids received into the second tunnel are passed to the holding tank and substantially all heavier-density liquids received into the second tunnel are passed to the discharge port of the first tunnel, thereby separating the light-density liquid and the heavier-density liquid.

A method for skimming and recovering hydrocarbons floating on the surface of a body of water, the method comprising:

• providing a floating hull defining a first tunnel having an inlet port and a discharge port, a second tunnel, and a holding tank for containing collected hydrocarbons;
• drawing subsurface water through the inlet port of the first tunnel, through the first tunnel and out the discharge port of the first tunnel;
• forming the second tunnel with a hydrocarbon/water inlet port positioned above the inlet port of the first tunnel and at the surface water level for receiving floating hydrocarbons and water into the second tunnel;
• directing water in the second tunnel down and toward an outlet port adjoining the first tunnel between the inlet port of the first tunnel and the discharge port of the first tunnel, such that the second tunnel is continually filled with water between its inlet port and its outlet port;
• pivotally securing a buoyancy-responsive skimming gate to the hull and defining in part the second tunnel;
• and
• passing substantially all hydrocarbons floating on the surface water in the second tunnel over the skimming gate and to the holding tank, thereby separating the hydrocarbons from the water.