Use of computational fluid dynamics in the design and optimisation of DAF basins

Operational experience with dissolved air flotation (DAF) basins in Europe and South Africa has demonstrated the importance of basin geometry on performance. It is typically the effect of high local velocities in critical locations of the basin which results in poor subnatant quality. The following design parameters have been identified by a variety of authors to play an important role in controlling these velocities: Inlet baffle placement Inlet baffle angle Inlet baffle height Basin depth Basin length-to-width ratio Method of subnatant withdrawal Method of float removal.