The effect of fan cooling towers on the generation of electricity by thermal power plants during the summer period

An urgent task for thermal power plants of ferrous metallurgy enterprises and a number of branches of the chemical industry is to increase the production of additional electrical power of thermal power plants in the summer by increasing the flow rate of air entering the cooling towers. This problem necessitates the development of a methodology for calculating power at various air supply values. The article presents a method for thermal power plants with the same type of turbines and a reversible cycle consisting of identical fan turbines, based on an integrated approach. It has been developed for determining the electrical power generated by turbogenerators depending on the air supply to fan cooling towers, taking into account the influence of heat and mass transfer processes in cooling towers and heat exchange in condensers on the value of steam temperature at the turbine outlet, as well as containing analytical dependencies for calculating the power of the turbogenerator on the temperature of the saturated steam at the turbine outlet. The paper gives an example of calculating power generation by turbogenerators of a thermal power plant in the summer. It demonstrates that at constant values of the flow rates of steam and water entering the condenser of the circulation cycle, the magnitude of the decrease in the water temperature in the cooling tower will remain practically unchanged. Therefore, the intensification of heat and mass transfer in the cooling tower due to an increase in air supply will lead to a decrease in the values of water temperatures at the entrance to the cooling tower and at the exit from it. It will also reduce the temperature of the steam after the turbine, which will increase the power production of turbogenerators. The considered example demonstrates that an increase in the flow rate of air entering the cooling towers from minimum to maximum values will increase the generation of electrical power for each T-50-130 TMZ turbine by 1.93-2.4 MW, while the greatest increase in power will be achieved at low values ambient temperature and relative humidity. The technique described in the article can be used to regulate the power generation of thermal power plants by changing the load of cooling tower fans.