Three Critical Aspects of UV Systems - Hydraulics, Hydraulics & Hydraulics : Whitley Burchett

Three Critical Aspects of UV Systems- Hydraulics, Hydraulics, Hydraulics

(Presented at the CWEA One-Day Specialty Conferences for
UV Disinfection, Dublin, CA June 16, 2004 and Whittier, CA June 18, 2004)

Casey LeBlanc: Whitley, Burchett & Associates

ABSTRACT

The hydraulic behavior of UV systems is critical because velocity and UV intensity, the two components that define UV dose, are distributed non-uniformly in UV reactors. Without proper consideration to hydraulics, a UV system may function inefficiently or not be able to meet disinfection requirements. This presentation will contrast the hydraulic design goals for UV disinfection with those of chlorination systems, and outline specific mitigation measures that can be used to improve UV disinfection performance.

For recycled water systems in California using UV disinfection, the focus of permitting has shifted to UV hydraulics. The presentation will detail how velocity profiling is a permitting option for UV owners provided that certain design and performance requirements are met. This permitting option is to the benefit of UV owners because velocity profiling can be less expensive than traditional bioassays and can shorten the permitting process for recycled water facilities with UV disinfection.