The Stage-2 Disinfectant and Disinfection By-Product (D/DBP) regulations force water utilities to be more concerned with their finished and distributed water quality. Compliance requires changes to their current operational strategy, which affect the formation of DBPs over time. This study quantifies changes in DBP formation and chlorine decay kinetics under different operational conditions and pipe materials found at many small-scale water utilities. A physical model (Pipe Loop) of a distribution system was used to evaluate the change in water quality from conditions such as having a high chlorine dosage entering the distribution system, using a chlorine booster system in the distribution system, and operation of clearwells/storage tanks. The High Chlorine Run (HC) is least favorable option with approximately 64% and 30% higher TTHMs than Normal Run (NR) and Chlorine Booster Run (CB), respectively. High Chlorine conditions also minimize the wall effects. The location of Boosters should always be after the storage systems to avoid extra contact time that can produce approximately 23% - 78% higher TTHMs. The following trends are discovered from the data analysis: Chlorine residual HC > CB > NR and TTHM NR > CB > HC.
R. Sadiq and M. J. Rodriguez, “Disinfection By-Products (DBPs) in Drinking Water and Predictive Models for Their Occurrence: A Review,” Science of the Total Environment, Vol. 321, No. 1, 2004, pp. 21-46. doi:10.1016/j.scitotenv.2003.05.001
US Environmental Protection Agency, “National Primary Drinking Water Regulations: Disinfectants and Disinfection Byproducts,” Federal Register, Vol. 63, No. 241, 1998, pp. 69390-69476.
B. Warton, A. Heitz, C. Joll and R. Kagi, “A New Method for Calculation of the Chlorine Demand in Natural and Treated Waters,” Water Research, Vol. 40, No. 15, 2006, pp. 2877-2884. doi:10.1016/j.watres.2006.05.020
C. Adams, T. Timmons, T. Seitz, J. Lane and S. Levotch, “Trihalomethane and Haloacetic Acid Disinfection By-Products in Full-Scale Drinking Water Systems,” Journal of Environmental Engineering, Vol. 131, No. 4, 2005, pp. 526-534.
J. Rook, “The Chlorination Reactions of Fulvic Acids in Natural Waters,” Environmental Science & Technology, Vol. 11, No. 5, 1977, pp. 478-482. doi:10.1021/es60128a014
M. C. Besner, V. Gauthier, B. Barbeau and R. Millett, “Understanding Distribution System Water Quality,” Journal of the American Water Works Association, Vol. 93, No. 7, 2001, pp. 101-104.
B. Carrico and P. C. Singer, “Impact of Booster Chlorination on Chlorine Decay and THM Production: Simulated Analysis,” Journal of Environmental Engineering, Vol. 135, No. 10, 2009, pp. 928-935.
R. M. Clark and M. Sivaganesan, “Predicting Chlorine Residuals and Formation of TTHMs in Drinking Water,” Journal of Environmental Engineering, Vol. 124, No. 12, 1998, pp. 1203-1210. doi:10.1061/(ASCE)0733-9372(1998)124:12(1203)
R. M. Clark, J. Q. Adams and B. W. Lykins, “DBP Control in Drinking Water; Cost and Performance,” Journal of Environmental Engineering, Vol. 120, No. 4, 1994, pp. 759-782. doi:10.1061/(ASCE)0733-9372(1994)120:4(759)
R. M. Clark, “Chlorine Demand and TTHM Formation Kinetics: A Second Order Model,” Journal of Environmental Engineering, Vol. 124, No. 1, 1998, pp. 16-24.
R. M. Clark, H. Pourmoghaddas, L. J. Wymer and R. C. Dressman, “Modeling the Kinetics of Chlorination By-Product Formation: The Effects of Bromide,” Journal of Water Supply: Research and Technology-Aqua, Vol. 45, No. 3, 1996, pp. 112-119.
N. B. Hallam, J. R. West, C. F. Forster, J. C. Powell and I. Spencer, “The Decay of Chlorine Associated with the Pipe Wall in Water Distribution Systems,” Water Research, Vol. 36, No. 14, 2002, pp. 3479-3488. doi:10.1016/S0043-1354(02)00056-8
T. Haxton, R. Murray, W. Hart, K. Klise and C. Phillips, “Formulation of Chlorine and Decontamination Booster Station Optimization Problem,” World Environmental and Water Resources Congress (ACSE), Palm Springs, 22-26 May 2011, pp. 199-205.
P. M. Jonkergouw, S. T. Khu, Z. S. Kapelan and D. A. Savic, “Water Quality Model Calibration under de Demands,” Journal of Water Resource Planning and Management, Vol. 134, No. 4, 2008, pp. 326-336.
R. M. Clark and B. K. Boutin, “Controlling Disinfection By-Products and Microbial Contaminants in Drinking Water,” National Risk Management Research Laboratory, Office of Research and Development, Cincinnati, 2001.
C. Li, J. Y. Yang, J. Yu, T. Zhang, X. Mao and W. Shao, “Second Order Chlorine Decay and Trihalomethanes Formation in Pilot Scale Water Distribution Systems,” Water Environment Research, Vol. 84, No. 8, 2012, pp. 656-661. doi:10.2175/106143012X13373550427390
P. C. Singer, H. S. Weinberg, K. Brophy, L. Liang, M. Roberts, I. Grisstede, S. Krasner, H. Baribeau, H. Arora and I. Najm, “Relative Dominance of Haloacetic Acids and Trihalomethanes in Treated Drinking Water,” AWWA Research Foundation/American Water Works Association, Denver, 2002.
D. L. Boccelli, M. E. Tryby, J. G. Uber and R. S. Summers, “A Reactive Species Model for Chlorine Decay and THM Formation under Rechlorination Conditions,” Water Research, Vol. 37, No. 11, 2003, pp. 2654-2666.
S. R. Poleneni, “Analysis and Management of Disinfection By-Product Formation in Distribution Systems,” M.S. Thesis, University of Missouri, Missouri, 2013.
APHA, AWWA and WEF, “Standard Methods for the Examination of Water and Wastewater,” 20th Edition, United Book Press, Baltimore, 1998.
J. W. Munch, “EPA Method 524.2: Measurement of Purgeable Organic Compounds in Water by Capillary Column Gas Chromatography/Mass Spectrometry,” Office of Research and Development, Washington DC, 1995.
C. G. Hill Jr., “Introduction to Chemical Engineering Kinetics and Reactor Design,” John Wiley & Sons, Inc., New Jersey, 1997.
A. E. Germeles, “Forced Plumes and Mixing of Liquids in Tanks,” Journal of Fluid Mechanics, Vol. 71, No. 3, 1975, pp. 601-623. doi:10.1017/S0022112075002765
W. M. Grayman and R. M. Clark, “Using Computer Models to Determine the Effect of Storage on Water Quality,” Journal of the American Water Works Association, Vol. 85, No. 7, 1993, pp. 67-77.
M. S. Kennedy, S. Moegling, S. Sarikelli and K. Suravallop, “Assessing the Effects of Storage Tank Design,” Journal of the American Water Works Association (JAWWA), Vol. 85, No. 7, 1993, pp. 78-88.
R. Mau, P. Boulos, R. Clark, W. Grayman, R. Tekippe and R. Trussel, “Explicit Mathematical Models of Distribution System Storage Water Quality,” Journal of Hydraulic Engineering ASCE, Vol. 121, No. 10, 1995, pp. 699-709.
A. A. Zachár and A. A. Aszódi, “Numerical Analysis of Flow Distributors to Improve Temperature Stratification in Storage Tanks,” Numerical Heat Transfer: Part A— Applications, Vol. 51, No. 10, 2007, pp. 919-940. doi:10.1080/10407790601184405