Many engineers size an ultraviolet (UV) disinfection
system based on design conditions of flow, UV transmittance
(UVT), and lamp output, and then assess
operation and maintenance costs based on average
flow. However, flow and UVT vary among water treatment
plants and response to these variables by the UV
system varies among equipment. As a result of the
limitations of this approach, many installed systems
today are significantly overdosing.
Simulations of the performance of UV system
alternatives that account for critical variables provide
the best foundation for selecting UV systems for
drinking water applications. This article provides an
overview of UV disinfection, identifying the benefits
of applying the key features associated with dose
monitoring, validation, and design and a new
approach for integrating these factors to obtain optimal
design. Includes 23 references, tables, figures.