Investigation of Improving Microbial Inactivation and Decreasing Operating and Maintenance Requirements for Existing UV Disinfection Systems

Ultraviolet (UV) systems have been widely used to disinfect secondary effluent from municipal wastewater treatment plants. This poster presents the results of an analysis of parameters that affect disinfection performance from several existing UV disinfection systems and investigates innovative approaches to affect these parameters to improve performance. Data from the following types of systems are analyzed: low pressure/medium output system with horizontally oriented lamps with manual cleaning, low pressure/medium output system with vertically oriented lamps with manual cleaning, and medium pressure/high output system with horizontally oriented lamps with automatic cleaning. Issues addressed include increasing wastewater UV percent transmittance, decreasing particle size distribution, and decreasing lamp cleaning frequency. The impact of slime and algae growth on microbial inactivation and how to mitigate that growth is also discussed.