The passive skimmer is a submersible trap specific for the recovery of LNAPL. The system is provided with a floating mechanism suitable to the fluctuations of the aquifer, which allows the entry of LNAPL, and a collecting tank for the product itself. The passive skimmer consists of a reamer (skimmer) dedicated to the oil / water separation, equipped with a float for the recovery with gravity. Another constituent part of the passive skimmer system is the collecting tank, located below the skimmer, useful to trap the floating product. The recovery of product happens with gravity; therefore, the effectiveness depends on the combination of viscosity and initial thickness. In the best conditions of viscosity and initial thickness, the passive skimmer is able to visibly reduce the layer of floating product. The passive skimmer must be manually extracted and emptied from the well. The total length of the passive skimmer is 180 cm and, of these, 40.5 cm constitute the effective skimming travel.
Materials: fiberglass, steel, Viton, tygon
External diameter: 60 mm
Specific gravity of extracted product: ≤ 0,85 g/cm3
Kinematic viscosity: 1-1000 cSt
Initial thickness of the product: from 20 mm to 70 mm (depending on the viscosity)