Impact of water quality and reactor hydrodynamics on wastewater disinfection by UV, use of CFD modeling for performance optimization

摘要

In order to ensure reliable operating conditions for adequate wastewater disinfection in a UV reactor, two aspects were investigated as having a critical impact on the disinfection performances: water quality and hydrodynamics of the water flow through the system. Tests performed with a collimator on several wastewater effluents enabled us to relate the UV inactivation to the total suspended solids content of the water to be treated, the influence being decisive under 5 mg/l TSS. On the other hand, a CFD (Computational Fluid Dynamics) numerical tool was used to provide an accurate characterization of the flow pattern within a vertical flow reactor. On the basis of such modeling, modifications in the geometry of the reactor could be proposed aiming at reducing zones of low dose and therefore improving disinfection performances. Side-by-side experimental comparisons between modified and unmodified pilots enabled us to validate that approach. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. [References: 11]