Evaluation of Disinfection Cost for Different Flow Regimes in Water Storage Tanks
Publication: Journal of Water Resources Planning and Management
Volume 147, Issue 4
Abstract
In water distribution systems, premature decay of disinfectants inside water storage tanks can increase the costs of disinfectant input, depending on the mixing type that takes place in the tank. In this paper, the influence of the flow regime of a water storage tank upon the disinfection cost was assessed. Equations relating disinfectant cost to the disinfectant’s decay rate and the mean residence time are presented and compared for three flow regimes: ideal mixed flow, ideal plug flow, and disperse flow. As the decay rate or the mean residence time increased, the cost went to the order of 100 times for plug flow, when compared to mixed flow. The dispersive flow regime presented disinfection costs that were up to 10 times the cost for the mixed flow regime. Given these differences, some general guidelines concerning baffling, inlet characteristics, and water depth-to-diameter ratio were presented in order to obtain a flow closer to the plug regime and, consequently, diminish the chlorination costs. Finally, a case study was presented, based upon the guidelines, showing that a change in the inlet diameter or inlet orientation of a water storage tank can reduce the chlorination cost.
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Data Availability Statement
The data about the “Example Application” (Fig. 3) and the Excel file that support the findings of this study (Figs. 1 and 2) are available from the corresponding author upon reasonable request by email.
Acknowledgments
The authors are indebted to the Brazilian research support foundations CAPES for the support of different stages of this study.
References
Boulos, P. F., W. M. Grayman, R. W. Bowcock, J. W. Clapp, L. A. Rossman, R. M. Clark, R. A. Deininger, and A. K. Dhingra. 1996. “Hydraulic mixing and free chlorine residual in reservoirs.” J. Am. Water Work Assoc. 88 (7): 48–59. https://doi.org/10.1002/j.1551-8833.1996.tb06584.x.
Clark, R. M. 2011. “Chlorine fate and transport in drinking water distribution systems: Results from experimental and modeling studies.” Front. Earth Sci. 5 (4): 334–340. https://doi.org/10.1007/s11707-011-0194-x.
Codina, R., J. Principe, C. Muñoz, and J. Baiges. 2015. “Numerical modeling of chlorine concentration in water storage tanks.” J. Numer. Methods Fluids 79 (2): 84–107. https://doi.org/10.1002/fld.4044.
Grayman, W. M., and R. M. Clark. 1993. “Using computer models to determine the effect of storage on water quality.” J. Am. Water Work Assoc. 85 (7): 78–88. https://doi.org/10.1002/j.1551-8833.1993.tb06026.x.
Grayman, W. M., R. A. Deininger, A. Green, P. F. Boulos, R. W. Bowcock, and C. C. Godwin. 1996. “Water quality and mixing models for tanks and reservoirs.” J. Am. Water Work Assoc. 88 (7): 60–73. https://doi.org/10.1002/j.1551-8833.1996.tb06585.x.
Grayman, W. M., and G. J. Kirmeyer. 2000. “Quality of water.” Chap. 11 in Storage water distribution systems handbook, edited by L. W. Mays, 11.1–11.38. New York: McGraw-Hill.
Grayman, W. M., L. A. Rossman, C. Arnold, R. A. Deininger, C. Smith, J. F. Smith, and R. Schnipke. 1999. Water quality modeling of distribution system storage facilities. Denver: American Water Works Association.
Grayman, W. M., L. A. Rossman, R. A. Deininger, C. D. Smith, C. N. Arnold, and J. F. Smith. 2004. “Mixing and aging of water in distribution system storage facilities.” J. Am. Water Work. Assoc. 96 (9): 70–80. https://doi.org/10.1002/j.1551-8833.2004.tb10704.x.
Hua, P., K. R. F. De Oliveira, P. Cheung, F. V. Gonçalves, and J. Zhang. 2018. “Influences of model structure and calibration data size on predicting chlorine residuals in water storage tanks.” Sci. Total Environ. 634 (Mar): 705–714. https://doi.org/10.1016/j.scitotenv.2018.03.364.
Montoya, C. P., S. Laín-Beatove, P. Torres-Lozada, C. H. Cruz-Vélez, and J. C. Escobar-Rivera. 2016. “Effects of water inlet configuration in a service reservoir applying CFD modelling.” Ing. Investigación 36 (1): 31–40. https://doi.org/10.15446/ing.investig.v36n1.50631.
Powell, J. C., J. R. West, N. B. Hallam, C. F. Forster, and J. Simms. 2000. “Performance of various kinetic models for chlorine decay.” J. Water Resour. Plann. Manage. 126 (1): 13–20. https://doi.org/10.1061/(ASCE)0733-9496(2000)126:1(13).
Rossman, L. A., R. M. Clark, and W. M. Grayman. 1994. “Modelling chlorine residual in drinking water distribution systems.” J. Environ. Eng. 120 (4): 803–820. https://doi.org/10.1061/(ASCE)0733-9372(1994)120:4(803).
Rossman, L. A., and W. M. Grayman. 1999. “Scale model studies of mixing in drinking water storage tanks.” J. Environ. Eng. 125 (8): 755–761. https://doi.org/10.1061/(ASCE)0733-9372(1999)125:8(755).
Rossman, L. A., J. G. Uber, and W. M. Grayman. 1995. “Modeling disinfectant residuals in drinking water storage tanks.” J. Environ. Eng. 121 (10): 752–755. https://doi.org/10.1061/(ASCE)0733-9372(1995)121:10(752).
Stache, N., T. Bleninger, B. Hofmann, G. Jirka, M. Maier, and K. Roth. 2009. “Mixing in drinking water storage tanks: Field and laboratory experiments.” In Proc., 33rd IAHR Congress: Water Engineering for a Sustainable Environment. Madrid, Spain: International Association of Hydraulic Engineering and Research.
Tian, X., and J. W. P. Roberts. 2008. “Mixing storage tanks. I: No buoyancy effects.” J. Environ. Eng. 134 (12): 974–985. https://doi.org/10.1061/(ASCE)0733-9372(2008)134:12(974).
Van Der Walt, J. J. 2002. “The modelling of water treatment process tanks.” Ph.D. thesis, Faculty of Engineering, Rand Afrikaans Univ.
WHO (World Health Organization). 2017. Guidelines for drinking-water quality. Geneva: WHO.
Xavier, M. L. M., and J. G. Janzen. 2017. “Effects of inlet momentum and orientation on the hydraulic performance of water storage tanks.” Appl. Water Sci. 7 (5): 2545–2557. https://doi.org/10.1007/s13201-016-0449-5.
Xavier, M. L. M., P. H. S. Lima, and J. G. Janzen. 2014. “Impact of inlet and outlet configurations on the mixing behavior in water storage tanks.” Eng. Sanit. Ambient 19 (3): 315–324. https://doi.org/10.1590/S1413-41522014019000000570.
Zhang, J. M., B. C. Khoo, H. P. Lee, C. P. Teo, N. Haja, and K. Q. Peng. 2013. “Numerical simulation and assessment of the effects of operation and baffling on a potable water service reservoir.” J. Environ. Eng. 139 (3): 341–348. https://doi.org/10.1061/(ASCE)EE.1943-7870.0000629.
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Published In
Journal of Water Resources Planning and Management
Volume 147 • Issue 4 • April 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: May 13, 2020
Accepted: Nov 15, 2020
Published online: Feb 15, 2021
Published in print: Apr 1, 2021
Discussion open until: Jul 15, 2021
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