Risk analysis of nitrification occurrence in pilot-scale chloraminated distribution systems

Abstract

Research Article| August 01 2007 Risk analysis of nitrification occurrence in pilot-scale chloraminated distribution systems Jian Yang; Jian Yang 1Earth Tech Inc., 200 Indiana Ave., Stevens Point, WI 54481, USA Tel.: 715/342-3052; Fax: 715/341-7390; E-mail: jian.yang@earthtech.com Search for other works by this author on: This Site PubMed Google Scholar Gregory W. Harrington; Gregory W. Harrington 2Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA Search for other works by this author on: This Site PubMed Google Scholar Daniel R. Noguera; Daniel R. Noguera 2Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA Search for other works by this author on: This Site PubMed Google Scholar Kala K. Fleming Kala K. Fleming 3American Water, 1025 Laurel Oak Rd., Voorhees, NJ 08043, USA Search for other works by this author on: This Site PubMed Google Scholar Journal of Water Supply: Research and Technology-Aqua (2007) 56 (5): 293–311. https://doi.org/10.2166/aqua.2007.007 Article history Received: April 17 2007 Accepted: April 19 2007 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Cite Icon Cite Permissions Search Site Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsThis Journal Search Advanced Search Citation Jian Yang, Gregory W. Harrington, Daniel R. Noguera, Kala K. Fleming; Risk analysis of nitrification occurrence in pilot-scale chloraminated distribution systems. Journal of Water Supply: Research and Technology-Aqua 1 August 2007; 56 (5): 293–311. doi: https://doi.org/10.2166/aqua.2007.007 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex The implementation of chloramine disinfection introduces free ammonia into drinking water distribution systems, and free ammonia serves as an energy source for ammonia oxidizing bacteria that cause nitrification. The occurrence of nitrification may be affected by many factors including temperature, pH, water age, chloramine residual, and chlorine-to-ammonia application ratio. No studies have been conducted to quantitatively evaluate the individual and total contributions of these factors to the risk of nitrification occurrence. This study evaluated the individual and total contributions of pH and other factors on nitrification occurrence using factorial-designed pilot-scale chloraminated distribution system experiments. The pilot-scale systems were operated at pH values of approximately 7.0, 8.0, and 9.0. Logistic models were developed to quantify the contribution of pH and other factors to the risk of nitrification occurrence in the pilot-scale systems. Results showed that pH, total chlorine residual, hydraulic detention time, and temperature were the significant factors that influenced the risk of nitrification occurrence. However, none of these factors appeared to be dominant in predicting the risk of nitrification occurrence under the studied conditions. A simplified model was able to predict the risk of nitrification occurrence in the pilot-scale systems based on a combination of pH, temperature, and total chlorine residual. The developed logistic models provide an easy-to-use tool for drinking water utilities to manage operation strategies to minimize the risk of nitrification occurrence based on ambient conditions (temperature and pH) and operating parameters (water age and chloramine residual). logistic, model, nitrification, risk analysis This content is only available as a PDF. © IWA Publishing 2007 You do not currently have access to this content.