Journal Article

Simulation of Chlorine Injection in Water Distribution Networks in Response to Contaminations

Pirooz, Moharram Dolatshahi, Karamouz, ‪Mohammad, Yousefi, Azadeh, Zahmatkesh, Zahra, Mahmoodzadeh, Davood

2022

Overview

Drinking water distribution networks (DWDNs) are susceptible to various chemical and biological substances and their probable reaction with residual chlorine in the pipes. In this study, a framework is proposed to evaluate the network’s vulnerability, and to effectively respond to contamination incidents. The formulated index, to analyze the DWDN’s vulnerability, represents the state of the system’s preparedness to widespread contamination considering water quality and supply criteria. Proposed alternatives to improve the network’s response to contamination hazards include pipe closure and chlorine injection policies. To optimize the number of nodes and dosage of booster chlorine injection, optimization routines are formulated using genetic algorithm. To draw on the potential benefits of the proposed methodology, the DWDN in the western part of Tehran, Iran, is selected. The study network is analyzed based on a head-driven simulation utilizing an interface with EPANET and water quality extension (EPANET-MSX). The results indicated that following pipe closure, the pressure level for certain nodes will increase up to 39%, which would be offset by the installation of pressure reducing valves in the network. Closing the pipes in response to contamination causes supply deficiency, and in result increases the system's vulnerability. Nodes connected to more pipes (such as J25, J36, J87) are the priority for chlorine injection with respect to the duration and amount of contamination. The proposed optimization routines resulted in vulnerability reduction of up to 37% in comparison with no booster chlorination to the network. The framework developed provides real-time alternatives to respond to DWDN contamination and measures the extent of their effectiveness on the network’s performance. This methodology can be extended and applied to water distribution facilities in other study areas.A framework is proposed to evaluate the drinking water distribution network response to chlorine injection policies and pipe’s closure.An index is formulated to assess the network’s vulnerability, with respect to the water quality standards as well as supplying the demand.Optimization algorithms are formulated to determine the optimal pattern of chlorine injection.

• Publisher: Springer Nature B.V
• Subject: Algorithms / Arsenic / Chemical contaminants / Chlorine / Closures / Contamination / Disinfection & disinfectants / Drinking behavior / Drinking water / Flow velocity / Genetic algorithms / Hydraulics / Injection / Nodes / Optimization / Optimization techniques / Pipes / Policies / Quality standards / Real time / Reservoirs / Residual chlorine / Routines / Simulation / Water distribution / Water engineering / Water quality / Water quality standards