Simulação fluidodinâmica da dispersão de poluentes a partir da chaminé de uma termelétrica.

Abstract

The growing worldwide demand for energy has led researchers to pursue enhancement technologies in order to maximize the generation of electricity in its different forms. Among the different methods of production is the energy produced by thermal power plants, which accounts for over 60% of the energy produced in the world. It is an energy generated from the combustion of fuels such as coal, diesel oil, natural gas, etc. Among the main problems caused by power generation in thermal power plants is the emission of gaseous pollutants into the air. The off-gas emitted from the flue of a fuel consists mainly of carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen oxides (NOx), among others, causing environmental and health problems. In this sense, this study aims to evaluate the fluid dispersion of pollutants emitted from the chimney of a thermal power plant through numerical simulations using CFD (ANSYS CFX 15.0). As turbulence model was used k   standard. Based on the experimental design simulations it was found that the most significant variable in the process was the pollutant emission rate followed by wind speed. From the results obtained it was found that the height of the emission source has a decisive influence on the dispersion; that the lateral variation of wind speed intensity and variation of the frequency with which the wind changes direction are decisive factors in the dispersion of gaseous species in the atmosphere; and that dispersion occurs more intensively under instable atmospheric conditions, at an angle of 30 ° and a frequency change of direction of 5 minutes.