INFLUENCE OF HEAT-EXCHANGE SURFACES FOULING FOR TPP STEAM TURBINES CONDENSERS ON THE AMOUNT OF NITROGEN DIOXIDE EMISSIONS

Abstract

Problem statement. One of the most polluting industries is the thermal power industry and therefore reducing the emission of harmful gases, in particular nitrogen dioxide, is an important environmental issue. Despite the decrease in the production of TPPs and CHPs of electricity compared to 2020 (by 12,5 %), at present their share remains significant in the entire electric power complex, which leads to environmental risks due to large emissions and discharges of harmful substances by these enterprises into environment. The magnitude of such emissions depends on the efficiency of the circulating cooling systems, which affects the rational use of fuel and water resources and, accordingly, the state of the environment. Increasing the temperature of the exhaust steam by reducing heat transfer through the fouled heat exchange surface increases the pressure in the condenser of steam turbines and reduces the power of the turbine, which increases fuel consumption and increases the amount of harmful substances emissions. One of these emissions is nitrogen dioxide, which is a harmful toxic compound and is classified as a greenhouse gas. The purpose of the work is to calculate nitrogen dioxide emissions depending on the thickness of the deposited layer on the heat exchange surface of the TPP steam turbine condensers. Conclusions. The concept of harmful emissions’ share associated with the emergence and growth of a pollution layer on the heat exchange surface of the TPPs’ steam turbines condensers, expressed in fractions of a unit, is introduced, and an analytical expression is obtained for this value. Based on the theories of fuel combustion, heat transfer, as well as the concept of harmful emissions’ share associated with the emergence and growth of a pollution layer, the dependence of the amount of harmful emissions associated with fuel combustion at TPPs on the thickness of the pollution layer on the heat exchange surface of steam turbine condensers is obtained.