Whitley Burchett

Filtration And UV Disinfection:
What Treatment Process Parameters Really Matter?

(Presented at the CWEA Annual Conference, Fresno, CA, April 2004)

Paul Friedlander, Whitley Burchett & Associates

ABSTRACT

Filtration followed by UV disinfection is an increasingly common treatment train used to meet discharge permit requirements and to produce tertiary recycled water. Discharge permits and recycled water regulations specify specific treatment process parameters that must be met by these treatment trains, including surface loading rate and turbidity for the filtration process, and coliform and delivered dose for the UV system. Other water quality parameters used to evaluate performance of filtration and UV systems include TSS, UVT, MS2, and particle size. This paper discusses these process and performance parameters with an emphasis on what information they provide and what really matters in assessing system performance. Important issues addressed include the interrelationship between filtration and disinfection performance, and whether currently regulated parameters are the best ones to assess performance.