DIFFERENT APPROACHES TO UV DISINFECTION AT TWO LARGE WASTEWATER FACILITIES IN METRO ATLANTA

The R.M. Clayton Water Reclamation Center (Clayton WRC) and the R.L. Sutton Water Reclamation Facility (Sutton WRF) are separated only by the Chattahoochee River, but have taken different approaches to using ultraviolet (UV) light disinfection as their primary plant disinfection system. The Clayton WRC, in the City of Atlanta, decided to use the same open channel, gravity flow, medium pressure, high intensity, UV disinfection system that the City had experience with at two other facilities. The Sutton WRF, in neighboring Cobb County, evaluated many alternatives and decided on a closed vessel, medium pressure, high intensity, UV disinfection system. The facilities are separated only by the river they both discharge into, but the differences in the systems used are significant. Construction on the open channel vessel is complete, and the system is operational. The closed vessel system is expected to be operational by the end of 2003. When completed, both systems are expected to be the largest UV disinfection systems of their type in the United States. This paper discusses the design approaches for these two large UV systems, and start-up and operational data of the open channel, gravity flow, medium pressure, high intensity, UV disinfection system at the Clayton WRC.