NUMERICAL STUDY OF THE DISPERSION OF AIR POLLUTANTS AS A RESULT OF CHEMICAL REACTIONS IN A THERMAL POWER PLANT

This article presents the results obtained by numerical modeling of the spread of pollutants formed during the combustion of fuel at an electric thermal power plant and their chemical reaction in the atmosphere. On the example of a real thermal power plant (Ekibastuz SDPP-1), the dispersion of NO and the product of NO₂ was modeled during a chemical reaction with oxygen. A notable feature of this thermal power plant is that the difference between the chimneys makes it possible to study the influence of the height of the source on the dispersion of pollution. To describe this process, the Navier - Stokes equations were used, consisting of the equation of continuity and motion. To check the mathematical model and the numerical algorithm, test problems were solved numerically. The aim of this work was to study the level of pollution concentration at different distances from the source. As a result, the mass fractions of concentration and product were determined. According to the data obtained, with increasing distance from the source, the concentration of pollution spreads more widely under the influence of diffusion. The further the distance from the pipe, the lower the concentration of the substance. As a result of a numerical study, the data obtained can be used for further studies of the problems associated with the spread of pollutants into the atmosphere for real atmospheric conditions, and can also allow in the future to predict the optimal distance from residential areas for the construction of thermal power plants, at which the concentration of emissions will remain at a safe level.

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