Global and local mass transfer coefficients in waste water treatment process by computational fluid dynamics

Gas-liquid mass transfer is a currently used process in the waste water tre atment industry. The objective today is to optimize the design and have a b etter control on the operation of these processes by using the CFD code AST RID in two-phase flow reactors. A source term which represents interfacial mass transfer is introduced, accounting for two-phase flow hydrodynamics, i t permits to predict accurately dissolved gas concentration in reactors suc h as laboratory airlift internal loop reactor and full scale activated slud ge basin. (C) 2001 Elsevier Science B.V. All rights reserved.