SAR’s biological water treatment facility is the largest hazardous wastewater treatment facility in Norway with an estimated annual handling capacity at 240 000 mᶟ. The uniqueness of the facility is its robustness and ability to treat a broad range and complex compositions of contaminanted water.
The wastewater is mostly generated offshore and includes oil-contaminated water, ballast water, wash water, engine room slop and heavy metal-contaminated wastewater.
Best Available Technology (BAT) is deployed securing optimal process conditions and environmental protection. Pre-treatment of contaminated wastewater is done by chemical processing in a dissolved air flotation (DAF) unit. Heavy metals, solids and hydrocarbons are removed in this process. Additional treatment of DAF sludge in a centrifuge reduce further wastewater volumes post treatment.
Biological Treatment in an activated sludge system removes dissolved organic compounds, nitrogen and phosphor from the pretreated wastewater. Electric blowers deliver air into fine bubble diffusers in the aeration basin, sludge settle in a clarification tank and is recycled back to the activated sludge system.
Excess sludge is removed from the biological system activated sludge and handled in a dewatering process. Treated water from the biological treatment is filtrated in a Dynasand filter removing any excess particles before discharge to sea.