Determination of the dew point of flue gas in different operation modes of an external air heater of the PK-38-4 boilers in "TPP Maritsa Iztok 2" EAD

The dew point of flue gases is different when burning different organic fuels. In thermal power plants burning coal as the main fuel, liquid or gaseous fuel is used as the start-up fuel. This means that in the process of start-up the energy boiler, we also have a change in the dew point temperature of the flue gases depending on what fuel we are burning at the moment: only ignition fuel; of a mixture of ignition and base fuel in different ratios; on base fuel only. The change in the dew point temperature of the flue gases can reach up to 100^oC, which can lead to an unfavorable operating mode, especially on the last heating surface along the flue gas path. Keywords: steam generator, dew point temperature, lignite coal, mazut, natural gas. (author)