Hydraulic study and optimisation of water treatment processes using numerical simulation

Until recently, water treatment plants were frequently designed solely on the basis of the biological, chemical and physical constraints of processes. Nowadays, the use of Computational Fluid Dynamics (CFD) software enables the dimensioning of water treatment processes by taking into account the real hydraulic behaviour of processes. That has be done for the Coliban Water Aqua 2000 project, which consists of the construction of three water treatment plants. The disinfection performance of three ozone contactors were compared using the CFD software, Fluent. Moreover, the CFD application has been extended to a large range of water treatment processes in recent years. The paper presents several of these: flocculation tanks, UV reactors and secondary settling tanks.