Modelling of Open-Circuit Cooling System Chemical Emissions to River Water via Blowdown Water, and their Impact on the Quality of Effluents Discharged

Introduction: Open-circuit cooling systems (OCCS), integral to industrial processes, often release blowdown water containing high concentrations of treatment chemicals. If unmanaged, these discharges pose substantial risks to aquatic ecosystems and human health. This study addresses the environmental implications of chemical emissions from OCCS blowdown by developing a predictive model to estimate contaminant concentrations in receiving water bodies.
Methods: The research employs a computational model based on mass balance equations to simulate the dynamics of chemical emissions from blowdown water. It incorporates key operational variables, including flow rates, degradation rates, and volatilization characteristics. The model evaluates two chemical dosing strategies: continuous and fractional, and their resultant pollutant dispersal patterns in river systems. Validation was conducted using empirical data from sulfuric acid (H₂SO₄) applications at the nuclear power plant between 2015 and 2022.
Results: The model showed strong agreement with observed sulphate ion concentrations in the receiving water body, confirming its predictive reliability. Continuous dosing resulted in stable levels of pollutants, while fractional dosing caused temporary peaks that did not exceed regulatory values.
Conclusion: The modeling of blowdown water reveals significant implications for river water quality and highlights the urgent need for more effective wastewater management strategies within industrial contexts. Validation with measured SO₄^2- concentrations confirmed the model’s accuracy, making it a valuable tool for guiding regulatory compliance and optimizing cooling water treatment practices.