Theoretical and experimental analysys of the evaporative towers cooling system of a coal-fired power plant

The paper presents a theoretical and experimental analysis of the cooling system of a 150 MW coal-fed power plant located in central Italy, where ten evaporative towers cool down the plant using water taken from a river. An updated research on the state-of-the-art evaporative tower cooling system has been carried out to show the theoretical analysis of the tower heat and mass balance, and taking into account sensible and latent heat exchanged during the processes which occur inside these towers. A long-term statistical data analysis has been carried out concerning the operation of the cooling towers; this information was correlated to the corresponding values of the environmental conditions of the site, and used to evaluate heat exchanged by the towers in the various conditions. The whole analysis permitted to evaluate the optimal conditions as far as the operation of the towers is concerned and to suggest an improvement of the plant. Finally, since plant re-powering has become quite a common issue today, the evaluation of the cooling system operation was conducted under the hypothesis of an increase in the plant nominal power of about 10%.