separatory substancji ropochodnych

Storm water

Oil derivatives separators

Effective storm water treatment thanks to oil derivatives separators


The current legislation requires the investors to use environmentally friendly solutions in respect to the treatment of storm water, municipal and process sewage contaminated by such light liquids as oil derivative substances, fats etc. The sedimentation-flotation devices, i.e. separating systems are used in specific conditions to separate the mineral suspensions and oil substances contained in storm water and industrial sewage discharged from the roads and accompanying structures. Uponor Infra’s offer includes Weho SL separators for separation of light liquids.

SL type series Weho separators are flow devices, whose purpose is to remove the non-emulsifying oil, petrol and separate mineral suspensions (sand, mud etc.). These devices are used in the systems of municipal sewage collection plants, storm water drainage systems at industrial facilities, in storm water drainage of transport, fuel or equipment depots, vehicle manoeuvring yards, car parks, roads, motorways and many other facilities.

Weho SL separator tanks are made of Weholite double-walled polyethylene pipes with ring stiffness in the SN2-SN8 range (according to PN-EN ISO 9969). The multi-stream plate-fins inserts used are resistant to biological decomposition and the action of petroleum substances. Separator inspection openings are adapted for installation with concrete rings or system manholes.


Product Catalogue
separator Uponor Infra

Advantages of separators


  • The possibility of using complete integrated devices (settling tank and separator) in large urban catchments without losing the efficiency and parameters of the entire system
  • Possibility to manufacture and connect large storm water collectors to the separators
  • Small recess of separators with a large working volume of the system
  • For use in sewage systems with a depth of up to 8m below the ground ordinate, in areas with traffic up to 100 [kN/axis], as well as in areas with mining damage up to and including category IV.

Flow separators with plate-fins inserts

Operating principle

Operating principle

The treatment process is conducted in two stages. The sedimentation process of mineral suspension (sand, mud) takes place in the sludge chamber. The storm water is transported to the separator following its pre-treatment in the integrated primary settling tank. The physical process of adsorption and coalescence is used in the separation chamber in addition to the gravity force.  Oil molecules accumulate on the surface of multi-stream parallel distributed plate-fin sections (adsorption), where they merge into bigger agglomerates (coalescence) and migrate in the lower side of plate-fin sections towards the surface forming the oil film.
The standard separators are equipped with the closing systems, which upon collecting maximum volume of light liquid in the separator automatically close its outflow thus preventing the contamination of the receiver tank.

Oil separator
Additional accessories

Additional accessories

  • Measuring probes for the amount of suspensions and oil substances accumulated in the separator with the sound alarm system and/or light alarm system (NT-SET, NT-OS)
  • Installations emptying the system facilitating the cleaning and maintenance of the separators (NT-U)
  • Emergency shut-off on the inflow to the separator
  • Systems for the intensity of the flow including the flow controller
  • Check valve at the outlet of the device.
check valve

Construction of storm water collectors in Nowe Polkowice

Uponor Infra delivered PEHD Weholite SN8 pipes with diameters dn 500 ÷ 1600mm with a storm water separation and pre-treatment system, as well as manholes. In the course of execution of the project the heavy and complex structures of concrete separators were replaced with the modern system of separation and pre-treatment of storm water in Weholite technology of diameter dn 3000mm.

More information on separators


Uponor Infra retention systems

Brochure ENG version

PDF 2.65MB

Product catalogue 2019

Product catalogue PL, ENG, RUS version

PDF 11.99MB

Uponor Infra - Reference projects

Brochure ENG version

PDF 4.51MB