Usage of thermosyphon for avoiding of low grade corrosion on the surfaces of air heaters and increasing of thermal efficiency of steam generators PK-38-4

The paper presents and analyzes new type air heater, which uses the thermosyphon’s technology, aims to replace the existing horizontal tubular air heater of first-degree for steam generators Nos.5,6,7 and 8 at TPP Maritsa East-2 in Bulgaria. The main advantage of the air heater with heat pipes is the ability to lower the temperature of exhaust gases to levels that are impossible for the conventional tubular air heaters, thus increasing the efficiency of the steam generator. Along with the increased energy efficiency, reductions in CO2, SOx and NOx emissions into the atmosphere are achieved. The preheating of the air, used for air combustion by recirculation relieving the operation and improving the combustion in the steam generator, is also reduced.