Numerical modelling of flow structures over an industrial site: effect of the surrounding buildings on dust emissions

Abstract

In this paper, three-dimensional numerical simulations are used to simulate the wind flow structure over coal stockpiles of a real configuration of a power plant. Two configurations are tested for various wind directions: the first one without representing the buildings and the second one with the surrounding buildings in the calculation domain. The wind flow properties over the full site and near the stockpile surfaces are analyzed in order to understand the dust emission mechanisms over the various tested configurations. The emission factor formulation, proposed by the EPA to quantify fugitive dust emissions from a stockpile, is used to check the particle emission rate for each considered configuration using the velocity fields given by the simulations. The analysis of the results from the two tested configurations shows by evidence that the topography of the industrial site exerts large perturbations on the flow structure over the site. This work shows that previous studies carried out without taking into consideration the topography of the site probably lead to an inaccurate estimation of the fugitive dust emissions. This study highlights the necessity to take into account the presence of surrounding buildings to estimate and quantify the particle emission rate on stockpiles. The study reported in this paper improves the understanding of fugitive dust emissions on industrial sites and in mining zones. These results will allow a more accurate and relevant evaluation of fugitive dust emissions from open storage systems on industrial sites and a better evaluation of its environmental impacts.