Improving the Efficiency of the Combined Recycle Cooling System of Medium-power Combined Cycle Power Units

Abstract

Among the important tasks for the operation of the main equipment of thermal power plants is ensuring the reliability and safety of work, which in turn also applies to the technical water supply system, which has a direct impact on both the quality of the plant equipment and the environmental situation in general. At present, the main problems of industrial water supply systems include corrosion of equipment and structures. Corrosion can be defined as the process of destruction of a metal through chemical or electrochemical reactions with the environment. As a result, metal oxides or salts are formed with a weaker structure, which causes destruction of the material. In cooling systems, corrosion causes two main problems. The first and most obvious problem is the destruction of equipment, which entails the cost of replacing it, discharges of pollutants into the environment and plant downtime. The second problem is a decrease in the efficiency of equipment operation associated with a deterioration in heat exchange caused by the accumulation of corrosion products in the heat exchanger. In addition, due to the precipitation of salt deposits on the heat-exchange surfaces, disrupting the processes of heat exchange (mainly calcium carbonate, sulfates and phosphates of zinc and magnesium). If the salt concentration in the water film near the heat exchange surface exceeds its solubility in the saturation state, salt precipitation occurs, which leads to the formation of a salt layer or scale on the heat exchange surface. This article discusses technologies to improve the efficiency of the combined recycle cooling system at thermal power plants.