RoOil Bypass 20% — hydrocarbon separator with integrated bypass.
EN 858. Bypass 20% for high peak flows. From NS 15/3 to NS 200/40 (15 to 200 l/s).
The RoOil Bypass 20% is an underground HDPE hydrocarbon separator, EN 858 certified, with an integrated bypass device. It treats 100% of the nominal flow — the excess peak flow (20% above nominal, typically unpolluted stormwater) is diverted untreated. Ideal for installations with high peak flows where the excess carries no hydrocarbons. 8 models from NS 15/3 to NS 200/40 for nominal flow rates from 15 to 200 l/s.
Bypass vs. Class I — which one to choose?
In a Class I separator with no bypass (such as the RoOil), 100% of the flow — including heavy rainfall peaks — passes through the separator. That requires a separator sized for the total peak flow, which increases the cost. Where peak flows are dominated by clean stormwater (open car parks with separated drainage), the bypass allows sizing for the nominal flow and diverting only the uncontaminated excess.
A 20% bypass means the separator accepts up to 1,2× the nominal flow rate before the bypass activates. Above that figure, the excess is diverted. For installations where contamination is concentrated in the base flow (rather than in storm peaks), this solution is more economical than an oversized Class I separator. For higher efficiency, see the RoOil Bypass 10% (bypass activates only at 1,1× the nominal flow rate).
The RoOil Bypass 20% advantages at a glance:
Sizing and cost
- ✓Sized for the nominal flow — not for the total peak
- ✓8 models from 15 to 200 l/s for installations of any size
- ✓A more economical solution than an oversized Class I separator
- ✓Datasheets and DWG files available for download
Structure and standard
- ✓EN 858 certified — the European standard for hydrocarbon separators
- ✓Bypass integrated into the tank — no additional external parts
- ✓Single-piece, weld-free HDPE tank: resistant to soil and groundwater
- ✓Suitable for open car parks with mixed stormwater drainage
Installation and maintenance
- ✓Access through a telescopic DN600 cover for maintenance
- ✓Emptying by vacuum tanker — no special tools
- ✓Inert HDPE — does not corrode, does not contaminate
- ✓For higher treatment efficiency, also available with a 10% bypass
The RoOil Bypass 20% in detail
- 1Telescopic DN600 coverAccess to the interior for maintenance and emptying. Telescopic extension adjustable in level.
- 2Flow baffleSlows the effluent at the inlet, improving the settling of solids and sludge.
- 3Settling chamberRetention of settleable solids and sludge ahead of the separation compartment.
- 4Separation chamberFlotation and retention of hydrocarbons by density difference.
- 520% bypass deviceActivates when the flow exceeds 1,2× the nominal rate. The unpolluted storm excess is diverted straight to the outlet.
- 6Outlet connectionDN200 to DN400 outlet depending on the model, for connection to the public sewer.
Supply includes: Single-piece HDPE tank with integrated bypass; settling chamber; separation chamber; 20% bypass device; inlet baffle; telescopic DN600 access points (1 or 2 depending on the model). DN200 to DN400 connections.
Dimensions and technical details
Prices exclude VAT at 23%. Subject to change without notice. For nominal flow rates below 15 l/s, see the RoOil Class I. For a lower bypass percentage, see the RoOil Bypass 10%.
Options and accessories
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