Final Settlement Tanks

Final settlement tanks are used for clarifying the final effluent at both activated sludge and trickling filter plants. Mass Flux Theory (MFT) assesses a settlement tank’s performance based on one dimensional settling theory.

As the flow through a final tank is not one dimensional and will exhibit non-ideal flow behaviour such as flow recirculation and short circuiting, the actual settling performance will usually be less than predicted by MFT.

MMI Engineering uses Computational Fluid Dynamics (CFD) simulation techniques to assess the internal hydro-dynamic performance of settlement tanks.

This allows MMI to assess the settling performance of an existing or new tank design and to optimise the effluent quality by optimisation of the tank geometry or inlet arrangement by inclusion or adaptation of internal stilling wells, Energy Dissipating Influents (EDIs) or baffles e.g. McKinney baffle.


Case Studies and Capability Statements

Budds Farm FST
Clarifier Seawater Incursion
Crossness EDI
Humus Tank
Phosphorous Removal

Reference Stories

Minworth STW