Ways of increase indicators of quality (heat economy) of power plants

The article analyzes performance indicators of thermal and nuclear power plants, namely thermal efficiency, and identifies the main ways to improve them. It is shown that the regenerative heating of the feed water is used in all steam turbine plants and significantly increases the thermal and overall efficiency of the plants. The higher the parameters of the steam in front of the turbine, the greater the temperature range for which condensate heating can be carried out, and the greater the effect of using a scheme with regenerative heating. It was determined that the regenerative heating of the feed water in the cycle with superheated steam also increases the efficiency, but the thermal efficiency of the regenerative cycle of superheated steam is always lower than the efficiency of the Carnot cycle at the same initial and final temperatures. It has been proven that at the same temperature of the feed water, the less underheating, the greater the work of the steam selection flow and the higher the thermal efficiency of the installation, and the greatest effect from regeneration occurs when using mixing type heaters. It is shown that for turbines with back pressure, regenerative heating increases the efficiency of the installation only when it is carried out by additional consumption of steam beyond what is required for production needs. In turbines with adjustable withdrawals, regenerative withdrawals located after the industrial one, based on the same amount of steam withdrawn, have a greater impact on the efficiency, and therefore sometimes the use of regenerative heating of the feed water can lead to an increase in efficiency even with a slight decrease in the consumption of steam to the consumer. The systematization and analysis of the existing methods for assessing the thermal efficiency of power plants of various types is carried out, the influence of energy consumption on own needs on the efficiency of power plants is shown.