Suction Heads / Suction Shovels / Suction Skimmers / Skimmer Heads are a variant of many different Oil Skimmers. They are coupled to the end of a hose and, via this hose, attached to a vacuum truck or a mobile pump. Suction Skimmers feature no
integrated pump, they simply constitute the optimized intake tract on the surface of the water.
When they are deployed, Suction Skimmers collect a higher amount of residual water than other oil skimmer systems and therefore it is appropriate to use additional oil water separators afterwards.
Operating conditions
Suction Skimmers can handle a wide range of viscosities. When used with high viscosity oils, the hose diameter or the maximum pump flow rate may reduce the recovery rate.
Solids must not hinder the oil to flow toward the Suction Skimmer. In the presence of high proportions of solids, additional filtration nets should be used, otherwise the inlet hose could get clogged.
Recovery rate and efficiency decrease with increasing wave motion. Best results are achieved in calm waters as the Skimmer lies optimally on the surface of the water.
The most effective way to use Suction Skimmers is in combination with passive Oil Booms. In lakes, the oil can thus be confined in order to form a closed surface and, in rivers, the oil can be accumulated. Both methods contribute to increase the effectiveness of the Suction Skimmer because the amount of residual water is reduced by the concentration of oil.
Generally speaking, the recovery capacity of the Suction Skimmer will be maximized in the presence of a thick layer of oil.
Suction Skimmers should not be used in fast flowing or choppy waters.
Suction Skimmers are also good for use in very shallow water, this due to their flat construction.
Suction Skimmers are often employed as a stationary skimming device.
Skimmer features
Suction Skimmer Heads are conceptually very similar to the Weir Skimmers but they have a simpler construction. They cannot separate oil from water, the supernatant oil layer is rather recovered by pump thanks to their good position on the surface of the water. It is particularly important in this regard to consider the amount of entrained water which varies depending on the conditions of use.
The Suction Head can be manually positioned making it possible to control the oil recovery rate. In their simplest form, Suction Heads have an inlet shaped in the form of a fan and, due to its appearance, this inlet is often referred to as duckbill or shovel head.
The oil is sucked up through the pressure of the pump and pumped into the skimmer head. The intake hoses should be fitted with floats, so that they will float horizontally on the suface of the water, as the Oil Skimmer does, and will not negatively affect the position of the Suction Skimer.