One of the main issues of condenser open recirculating cooling systems is scaling. This can have high economic consequences due to a loss of thermal exchange, and increase of maintenance costs and potentially plant shutdown. To tackle this problem, EDF, which operates 30 condenser open cooling circuits in nuclear power plants in France, has developed a modeling computer program called CooliSS, to help optimize chemical treatment. CooliSS is based on a chemical mass balance model and can provide previsions of cooling water chemistry evolution within the cooling circuit, as a function of operating conditions. The software was developed under the open source environment Scilab/Xcos. Phreeqc is used for the calculation of water chemistry in each component of the circuit (chemical speciation, pH and saturation index calculation, etc.). The model is based on theoretical considerations. A case study will be presented in this paper.
