Method of heat and mass transfer calculation of cooling technical water process at CHP plant when cooling pond with spray devices is operated

Abstract

The generation of electrical energy at thermal and nuclear power plants is associated with outward heat transmission of large amount. Cooling devices (cooling towers, spray pools, reservoirs) are used for its utilization. The increase of the efficiency of the cooling capacity of this equipment in the circulating water supply system of the CHP plant is occurred due to a decrease of temperatures that meet the optimal technical and economic performance of the facility. The studies of I.I. Makarova, V.A. Gladkova, B.S. Farfarovsky, Z.K. Maimekova, S.A. Suprun are devoted to these issues. The aim of the study is to develop a methodology to calculate the process of cooling technical water to create an operating temperature mode of the equipment during condensation of the waste heat of steam turbines and to minimize the amount of additional water from the Tom River in the warm season. To evaluate the operation of spray devices the authors have used experimental data obtained during the survey of the cooling pond of the West Siberian CHP plant in Novokuznetsk city and methods of physical modeling of heat and mass transfer. To increase the efficiency of technical water cooling at the CHP plant, it is proposed to install spray devices in addition to the existing cooling pond. A method has been developed to calculate the process of water cooling in spray devices during collaboration with a cooling pond. The method is based on the calculation of the optimal water temperature at the intake point in accordance with the operating parameters of turbine generator condensers. The method differs from the existing ones as it considers the influence of heat transfer and mass transfer phenomena in the boundary layer near the surface of dispersed drops water. The experimental and calculated results confirm that the use of spray devices in the cooling pond reduces the amount of additional water taken from the Tom River compared to its limit flow by almost 10 times at the established temperature difference during the condensation of exhaust steam in the summer period of the year. The method to calculate the cooling of technical water in a cooling pond with spray devices is recommended for implementation at the West Siberian CHP plant in Novokuznetsk city.