Applied Chemical Engineering

Integrated Life Cycle Assessment of a Conventional Drinking Water Treatment Plant during The Operational Phase: Linking Environmental Impacts to Energy and Chemicals Consumption

Ali T. Alzeyadi

Department of Civil Engineering, College of Engineering, University of Al-Qadisiyah, 58001, Al-Qadisiyah, Iraq

Ahmed M. AL-Sulaiman

Department of Civil Engineering, College of Engineering, University of Al-Qadisiyah, 58001, Al-Qadisiyah, Iraq

Ali W. Al-Attabi

Department of Civil Engineering, College of Engineering, University of Wasit,52001, Kut, Iraq

DOI: https://doi.org/10.59429/ace.v9i2.5960

Keywords: Reaction kinetics, Coagulation mechanism, Chlorination chemistry, Process optimization, Chemical engineering, Water treatment processes, Energy–chemical interaction

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Abstract

Drinking water treatment relies heavily on chemical processes such as coagulation and disinfection, where reaction efficiency directly influences operational performance and environmental impact. However, conventional systems often operate under design assumptions that overlook real-time variations in reaction conditions and energy–chemical interactions, leading to suboptimal performance. This study aims to investigate the reaction mechanisms governing alum-based coagulation and chlorine disinfection in a full-scale water treatment plant and to optimize their operational efficiency. A combined methodology integrating field-scale data acquisition, reaction pathway analysis, and process evaluation was employed to assess chemical consumption, energy use, and sludge formation. The findings reveal that inefficiencies in mixing and dosing significantly affect reaction completion, increasing chemical demand and energy consumption. Optimized process conditions improved coagulation efficiency and reduced excess chlorine usage. The study demonstrates that a reaction mechanism–based approach can enhance process efficiency and sustainability in water treatment systems.ons.

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