LAMELLA OR COALESCING INSERT?

SEPARATOR WITH LAMEL  OR COALESCING INSERT? 

Oil substances separators are devices designed to capture oily substances from rainwater, eg mineral oils, gasoline, light lubricants, etc. These devices are used to treat sewage from industrial areas, parking lots, roads, before feeding them into the sewage system. Wastewater treatment in separators is mechanical. Fine sand particles fall to the bottom (sedimentation) and in the upper part collect oils and emulsions (flotation). The remaining sewage flows to the sewage system. In order to accelerate the separation, coalescing or lamella inserts are used, respectively.

The PN-EN 858: 2005 standard indicates two classes of separators:

• Class I - coalescence separators for which the concentration of petroleum products at the outflow must be below 5 mg / l;
• Class II - gravity separators for which the concentration of petroleum products on the outflow must be below 100 mg / l.

Class II separators can be used only when pre-treated rainwater is discharged to the municipal sewage system.

If the water from the separator is not subjected to further purification processes, class I separators should be used. The inserts used in class I separators are described below.

Coalescing insert

The principle of operation in a separator with a coalescing insert

Substancje oleiste zawarte w ściekach osadzają się w wyniku sedymentacji i filtracji w materiale koalescencyjnym. Larger oil particles float upwards and smaller droplets of mineral oil deposti on the filter surface (coalescence) until large enough particles are formed that detach from the filter and rise to the surface to the oil layer. The treated sewage flows out through a siphoned outflow.

Lamella insert

The principle of operation in a separator with a lamella insert

The separation of pollutants in lamella separators takes place during the multi-layered flow of polluted waters through the lamella insert. The smallest drops of oil, the dimensions of which do not allow them to separate from the water, merge into larger drops and, after obtaining the appropriate size, they break away from the lamella filter and float to the surface. In addition, the insert reduces the flow of wastewater, which allows for the retention of easily sedimenting suspensions collected at the bottom of the separator.
For more information on this subject, please visit the PETROLEUM SEPARATORS section