Operational cost saving while improving effluent quality Optimising propeller and aerator configuration

The problem we solved

Our client Waterschap De Dommel was facing increased oxygen levels near the inlet of the anoxic zone, where oxygen is unwanted (WWTP Eindhoven, NL). Making design or operational changes in this large plant (running 24/7) is not straightforward and a trial and error approach is risky and costly.

Our approach

We simulated 1 of the 3 identical bioreactors of the 750,000 p.e. WWTP. We applied our proprietary multiphase WWTP CFD model, integrating biokinetics, so besides flow patterns, we could accurately visualise oxygen and nutrient concentrations in 3D. We tested 9 different scenarios to optimise plant performance both in terms of performance and cost (operational or design changes and hybrid combinations).


  • 10% reduction of unwanted oxygen just by making an operational change (no investment)
  • 20% reduction of nwanted oxygen by making an operational + design change
  • Significant energy cost saving (measure currently being implemented and yet to be quantified)
  • We implemented world's most validated WWTP CFD model, very closely matching reality learn more
  • Potentially increased aeration efficiency (to be confirmed)



Questions about this project?

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World's most validated WWTP CFD model

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Secondary settler optimisation

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Scale-up of a novel MBR reactor

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Scale-up of a novel ozonation system

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Ion exchange optimisation

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