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Chlorine decay studies in water supply system
1Dept. of Civil Engineering, Walchand College of Engineering, Sangli, 416 415, India. gurumunavalli@yahoo.co.in
Journal of Environmental Science & Engineering
|December 1, 2010
Summary
Maintaining water potability requires understanding chlorine decay. This study evaluates chlorine reaction models in different water types, finding reaction rates depend on water quality and initial chlorine concentration.
Area of Science:
- Environmental Science
- Water Treatment Engineering
Background:
- Municipal water quality is crucial for public health, with residual chlorine serving as a key indicator.
- Chlorine consumption, driven by bulk and wall reactions, dictates treatment plant dosage and impacts water potability at the consumer end.
- Understanding chlorine decay dynamics is essential for effective water quality management.
Purpose of the Study:
- To investigate the variability of bulk water chlorine reaction rates across different water qualities: raw, sand-filtered, and distributed water.
- To evaluate the applicability of first-order and two-component second-order models for representing bulk water chlorine reactions.
- To determine the range of reaction rate parameters for these models and assess the influence of initial chlorine concentration.
Main Methods:
- Studied chlorine reaction rates in raw, sand-filtered, and distributed water from a municipal water works.
- Applied first-order and two-component second-order kinetic models to bulk water chlorine reactions.
- Analyzed the impact of varying initial chlorine concentrations and conducted rechlorination studies on sand-filtered water.
Main Results:
- Chlorine reaction rates significantly vary with water quality, affecting chlorine decay.
- Reaction rate parameters were determined for both first-order and two-component second-order models.
- Reaction rate parameters showed an inverse relationship with initial chlorine concentration.
- Repeated rechlorination demonstrated a reduced chlorine-consuming capacity in sand-filtered water over time.
Conclusions:
- The study provides insights into chlorine reaction kinetics in different water matrices, aiding in accurate water quality modeling.
- The determined parameter ranges assist modelers in selecting appropriate input values for simulating chlorine decay.
- Water quality significantly influences chlorine reaction rates, necessitating tailored approaches for effective disinfection and maintaining potability.
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