Investigation on atmospheric dispersion of limestone particulates at the sea port

Abstract

In this study, low-level dispersion of particulates discharged during handling of limestone at the harbour is modelled using AERMOD software. The influences of key meteorological and operational variables on distribution of particulates are also studied. The key variables such as wind velocity, limestone water level, relative humidity, ambient temperature, and limestone drop elevation are considered for this study. In low-level emissions (0 m to 8 m from sea level) atmospheric temperature and relative humidity have a weak negative correlation with particulate concentration. Wind velocity, limestone moisture content and limestone drop elevation have a considerable effect on the distribution of particulates. At wind velocities (<3m/s) the limestone particles continue hovering in the atmosphere for a longer period and reach longer distance from the source of the particulate pollution. The concentration of particulates decreases with rise in limestone moister level. For low-level emissions, limestone moisture level and limestone drop elevation are important operational variables in dispersion of emissions. The model results are validated with measured values of the particulate concentrations and it is observed that predicted levels of PM10 and PM2.5 are in concurrence to that of measured levels of PM10 and PM2.5 with mean error of 21 % and 19.37 % respectively.