AWWA WQTC62514

Chemical reagents mixing within raw water appears at several stages of the drinking waterprocess. In particular, in the clarification step, coagulant and flocculant (or polymer aids) dosageand mixing within raw water have to be efficient to avoid over-dosage, reducing expensesand limiting residual reagent leakage. Computational Fluid Dynamics (CFD) modeling allows toassess the corresponding mixing device efficacy before implementing it on site. Full-scale datacan be used to reproduce the phenomena involved inside the process. In this study, three applications ofmixing assessment through CFD are considered: two designs of flash mixing for coagulantdispersion are compared, residence time distribution is studied for a potential extra mixingchamber and injection system location and efficacy for coagulant-aid are studied on full-scaledata. Optimum operating conditions, optimum device location and predictive behavior can bederived from CFD, to support the operator in its technical optimization of mixing devices. Includes 6 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2005

Number of Pages:

16

File Size:

1 file , 920 KB