Improved effluent predictions (secondary settler) Accounting for discrete settling

Combining hydrodynamics with flocculation model

Flocculation processes and its influencing factors (e.g. tank hydrodynamics) are generally not studied in detail. Classical models do not account for the interaction between activated sludge particles but simply use a lumped variable such as the sludge concentration. However, next to concentration also specific properties of the flocs such as size, density and porosity will have an important influence on the settling performance. These properties were included using PBM. This thorough understanding of flocculation processes in clarifiers could improve their design and operation, which can significantly improve the settling performance and control (both with respect to recycle flow and effluent quality).

Major findings

  • Combination of flocculation and CFD model gave valuable insights
  • Specific locations where flocculation takes place could be known
  • This combination of models could be used to optimise the design of settling tanks (e.g. baffle structure, inlet)

Improving mixing in large WWTP

CFD Activated Sludge WWTP

Improving aeration in a WWTP

CFD Activated Sludge WWTP

Quantifying N2O emission in WWTP

CFD N2O WWTP Activated sludge

Ion exchange optimisation

Ion Exchange CFD Optimisation

Design of a crystalliser

Crystalliser design CFD struvite

Improving mixing in a water reservoir

Drinking Water Reservoir Flow Pattern