Numerical and experimental studies of water disinfection in UV reactors

Li, H. Y.; Osman, Hafiiz; Kang, Chang Wei; Ba, Te; Lou, Jing

doi:10.2166/wst.2019.394

Cited by 4 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such damage further disables microorganisms from replication and infection. In this way, microorganisms are rendered unable to function or reproduce and might even be killed 95,96 . Mercury-based lamps are often used as the UV emission source for the disinfection system.…”

Section: Uv Disinfectionmentioning

confidence: 99%

A critical review of point-of-use drinking water treatment in the United States

Cao

Tong

et al. 2021

npj Clean Water

View full text Add to dashboard Cite

Ensuring safe water supply for communities across the United States is a growing challenge due to aging infrastructure, impaired source water, strained community finances, etc. In 2019, about 6% of public water utilities in the U.S. had a health-based violation. Due to the high risk of exposure to various contaminants in drinking water, point-of-use (POU) drinking water treatment is rapidly growing in popularity in the U.S. and beyond. POU treatment technologies include various combinations of string-wound sediment filters, activated carbon, modified carbon, ion exchange and redox media filters, reverse osmosis membranes, and ultraviolet lamps depending on the contaminants of concern. While the technologies are well-proven, highly commoditized, and cost-effective, most systems offer little in the way of real-time performance monitoring or interactive technology like other smart home appliances (e.g., thermostats, smoke detectors, doorbells, etc.). Herein, we review water quality regulations and violations in the U.S. as well as state-of-the-art POU technologies and systems with an emphasis on their effectiveness at removing the contaminants most frequently reported in notices of violations. We conclude by briefly reviewing emerging smart water technologies and the needs for advances in the state-of-the-art technologies. The smartness of commercially available POU water filters is critiqued and a definition of smart water filter is proposed.

show abstract

Section: Uv Disinfectionmentioning

confidence: 99%

A critical review of point-of-use drinking water treatment in the United States

Cao

Tong

et al. 2021

npj Clean Water

View full text Add to dashboard Cite

show abstract

“…Despite the reduced accuracy of RANS with certain turbulence models, studies using RANS models [11,12,[18][19][20][21][22][23], however, remained the dominant approach for UV reactor simulations in recent decades due to their efficiency. We note particularly that correct simulations of flow separation around cylindrical UV lamps are key to the improvement of numerical accuracy.…”

Section: Introductionmentioning

confidence: 99%

Performance of Reynolds Averaged Navier–Stokes and Large Eddy Simulation Models in Simulating Flows in a Crossflow Ultraviolet Reactor: An Experimental Evaluation

Zhang,

Law

2024

Water

View full text Add to dashboard Cite

Computational Fluid Dynamics (CFD) has been increasingly adopted as a design tool for the simulation of UV disinfection efficiency and the optimization of the configuration of a UV reactor. However, the performance of CFD with different turbulence closures may vary significantly. In the present study, an experimental evaluation was performed to assess the performance of CFD with five Reynolds Averaged Navier–Stokes (RANS) turbulence closures and three Large Eddy Simulation (LES) sub-grid scale (SGS) models. A simplified crossflow reactor with a single lamp sleeve was fabricated for the experimental measurements and numerical simulations. Overall, the superior performance of LES compared to RANS models in flow predictions within a complex configuration is demonstrated.

show abstract

Computational analysis of three lamp close conduit water disinfection UV reactor

Sultan

Ahmad

Hayat

et al. 2021

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

The purpose of ultraviolet (UV) disinfection is to bring to end the growth and procreation of microorganism. UV reactors are used for the UV disinfection of the drinking water. Our goal of the current research work was properly locating the positions of the UV lamps in a three-lamp close conduit water disinfection UV reactor. Three positions of UV lamps are based on vertices of the four basic types of triangles (Equilateral, Right angle, Scalene and Isosceles). The objective function for optimized lamp positioning was Reduction Equivalent Dose (RED). To ascertain efficient UV dose delivery to pathogen, water disinfection UV reactors was simulated with the aid of computational fluid dynamics. The computational investigation was achieved employing ANSYS ® Fluent 15.0 academic version. The turbulent flow was modeled using standard k−ε model, fluence rate (FR) was modeled using UVCalc3D model and pathogen transport was modeled using discrete phase model. The scalene lamp positioning results in highest RED value and isosceles lamp positioning results in lowest RED value. There is meager difference between the RED values of equilateral and scalene lamp positioning. Moreover, we found two lamps on the upstream side and one lamp on the downstream side results in better UV disinfection. The proposed methodology for the three-lamp model provides useful insights to the design and optimization of close conduit water disinfection UV reactor. This research work has evaluated, for the first time, a systematic methodology for three-lamp positioning to ameliorate the performance of UV reactor and has revitalized the comprehension about the contribution of FR distribution within the UV reactor. KeywordsCFD • Fluence rate • Reactor design • Turbulence modeling • UV lamp • Water disinfection List of symbols A and B Constants in logarithm microbial inactivation rate function dt Pathogens residing time (s) I Irradiance of UV radiation (W m −2 ) k Inactivation rate constant (m 2 J −1 ) K in Turbulent kinetic energy (m 2 s −2 ) N Pathogen influent ( −) N 0 Pathogens effluent ( −) N/N 0 Log inactivation ( −) p Means pressure ( −) t Time (s) u i and u j Velocity components (m s −1 ) u in Velocity at inlet (m s −1 ) u i u j Reynolds stress tensor (m 2 s −2 ) ij Kronecker delta function ε in Turbulent dissipation at inlet (m 2 s −3 ) Laminar kinematic viscosity (m 2 s −1 ) t Turbulent kinematic viscosity (m 2 s −1 ) Density (kg m −3 ) k Prandtl-Schmidt number for K in ( −) Prandtl-Schmidt number for K (−) Subscripts i, j Position of a cell in Inlet Abbreviations CFD Computational fluid dynamics DBPs Disinfection-by-products DPM Discrete phase model FR Fluence rate RED Reduction equivalent dose SURF Simultaneous UV FR and fluid dynamics Editorial responsibility: Samareh Mirkia.

show abstract

Numerical and experimental studies of water disinfection in UV reactors

Cited by 4 publications

References 14 publications

A critical review of point-of-use drinking water treatment in the United States

A critical review of point-of-use drinking water treatment in the United States

Performance of Reynolds Averaged Navier–Stokes and Large Eddy Simulation Models in Simulating Flows in a Crossflow Ultraviolet Reactor: An Experimental Evaluation

Computational analysis of three lamp close conduit water disinfection UV reactor

Contact Info

Product

Resources

About