Non-aqueous phase liquids (NAPLs ) are organic liquids such as fuel oil and gasoline that are sparingly soluble in water and are not subject to efficient removal by other technologies.

PRM Product Skimming


Non-aqueous phase liquids (NAPLs ) are organic liquids such as fuel oil and gasoline that are sparingly soluble in water and are not subject to efficient removal by other technologies. Because they do not mix with water, they form a separate phase. NAPLs can be lighter than water (LNAPL) or denser than water (DNAPL). NAPL contamination commonly exists as a separate organic phase that becomes trapped or sorbed within a given formation.

FAP Plus Zero Water LNAPL recovery

The FAP Plus system is used to recover LNAPL in 2-inch and larger-diameter wells up to 200 feet deep. It is an automated, in-well system to recover light-end hydrocarbons with SSU values of 80 or lower. The ZW and PPS features add to the ease of installation and ensure that only product will be recovered.


     •   Integrated high water shut prevents recovery of water

     •    PPS identifies product/water interface for simple installation

     •   36” travel rod skimmer

     •   High-viscosity skimmers

     •   Pump has been field-proven for over 20 years

F.A.P. Plus ZW (Zero Water)

The FAP Plus ZW is a pneumatic skimming system designed to recover product only in 2” and larger wells. The FAP Plus ZW is versatile enough to recover a wide range of products, from gasolines, diesel fuels, and hydraulic fluids, to more viscous products like # 6 heating oils. The FAP Plus ZW incorporates a ZW (Zero Water) feature and a Precise Positioning System (PPS). The Zero Water pneumatic logic stops and starts the FAP Plus pump automatically, depending on the position of the skimmer inlet. This prevents water from being recovered. The Precise Positioning System (PPS) will locate the product/water interface accurately so the skimming system is easily positioned.


ZW Zero Water

The intelligent logic incorporated in the FAP. Plus ZW will start or stop the pump based on the skimmer inlet position. When the water table rise exceeds the standard travel of the skimmer, the float will activate a pneumatic switch, shutting the air supply off and stopping pump operation. When the water table recedes and the skimmer inlet is at the proper product/water interface, the pneumatic switch is released, allowing the pump to re-start automatically. This feature ensures that only product is recovered.


Precise Positioning System (PPS)

The Precise Positioning System includes a surface-mounted pressure gauge to conveniently identify the product/water interface (PWI). When the FAP Plus ZW pump system is lowered into the well, the surface mounted gauge will show a drop in pressure indicating that the PWI has been reached. The system is then raised to accommodate the expected water table fluctuations and the pump will begin to cycle. If the PPS shows no air pressure, this indicates that the Zero Water function is activated and the pump has been turned off due to the high water table condition. When the water level recedes or the pump is repositioned the pneumatic Zero Water switch is turned on allowing the pump to cycle. The PPS gauge will show an increase in air pressure indicating pump operation.

Solar NAPL

The Solar NAPL provides the option to use the FAP Plus skimming system where power may not be available. The system uses solar power to operate the internal air compressor to power the FAP Plus pump.

FAP Plus Pump

The FAP Plus Pump consists of a flexible, special inner bladder and a flexible Buna-N® outer hose for the pump body. The pump operates by an integral controller that alternates air inflating and deflating the annular space between the inner bladder and the outer hose. When compressed air is applied, the inner bladder collapses, expelling the fluid to the surface. When the air is exhausted, the inner bladder rebounds to its original shape, thereby causing a suction which pulls fluid into the pump. The pump is capable of producing a suction of 17 inches of mercury, enough to recover viscous product and operate in deep wells up to 200 feet.


The skimmer is attached to the bottom of the FAP Plus ZW™ pump and is used to separate the product from the water in the well. Three types of skimmers are available: standard, high-viscosity, and density.

Standard Rod Skimmer

Is used to recover gasoline, jet fuel, and most diesel fuels. It combines a density float, hydrophobic element, product bypass screen, hollow guide rod and coiled hose. The center guide rod allows the skimmer to travel freely in response to water table changes. The skimmer is designed to float with the inlet positioned at the water/product interface, providing up to 36 inches of skimmer travel. The hydrophobic element is made of a special porous material with a pore size that will allow only product to pass. The bypass screen on top of the hydrophobic element allows the product to enter the skimmer directly when the product layer is greater than 2 inches.

High Viscosity Skimmer

Is used when the product has a viscosity higher than 80 SSU, such as oils. The 4-inch high viscosity skimmer uses the same design as the TR-517, minus the hydrophobic and bypass screen. The skimmer has 30 inches of travel and a specific gravity of 0.95, allowing it to float at the water/product interface. The product collects on top of the skimmer inlet and from there it is pumped to the surface. In normal applications, the skimmer will remove product down to a product layer of ¼ inch to ½ inch. The skimmer can be adjusted in the field to remove the product even further and attain a thinner layer.

Density Skimmers

Density skimmers are used when there is less than 18 inches of fluid from the bottom of the well to the water/product interface. These skimmers have a specific gravity of 0.95 and float in the water with the top inlet just above the product/water interface. The 2-inch, 4-inch, and 6-inch sizes are for use in well casings with these nominal inside diameters.

Tank- Full Shut-Off

The tank-full shut-off is installed on the recovery tank or drum to prevent overfilling of the product storage vessel. The main air is supplied to the inlet side of the overfill device and the outlet air supply to the F.A.P. Plus ZW pump. The overfill device is triggered by increased fluid levels in the recovery tank and mechanically shuts-off the air supply to the F.A.P. Plus ZW pump. The standard overfill device can be used with up to five pumps and installs into a standard 2-inch bung.


Include compressor packages, well caps, tubing, suspension cable, and membrane dryers.


PRM Filtration is a tradename of
Product Recovery Management, Inc. (PRM)

200 20th Street

Butner, North Carolina 27509


Main Phone: 919-957-8890

Toll Free: 1-888-873-2848

Fax: 919-957-7230

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