Dispersion Modelling of Air Pollutants from Industrial Point Sources

Industrial point sources emit a wide spectrum of air pollutants, posing significant threats to environmental quality and public health. Previous studies often focused on single pollutants or limited source types, reducing generalizability. This study addresses this gap by characterizing multiple pollutants gaseous emissions, particulate matter, and heavy metals across diverse industrial point sources and modelling their dispersion to assess spatial impacts on air quality.

Emissions were assessed from industrial facilities, including boilers, furnaces, kilns, and generators. Gaseous pollutants (HC, NOₓ, CO, VOC) were measured using an E8500 combustion analyzer, particulate matter (PM) was collected on quartz fiber filters with a high-volume air sampler and quantified gravimetrically, while heavy metals (Pb, As, Cd, Co, Zn) were analyzed via X-ray fluorescence (XRF). Dispersion modelling was conducted using AERMOD under five operational scenarios and ten pollutants.

Dispersion modelling revealed notable heterogeneity in pollutant concentrations across scenarios. In Scenario 1 (boiler-only operation), predicted ground-level concentrations of Pb (147.292 μg/m³), As (30.476 μg/m³), and Cd (30.474 μg/m³) were high, while NOₓ (0.010 μg/m³) and CO (0.019 μg/m³) remained low, emphasizing the source-specific nature of emissions.

The disproportionately high heavy metal concentrations highlight the need for targeted control of specific industrial processes, particularly boilers. Despite the reliability of AERMOD, dependence on a single dispersion model is a limitation.

This study presents a comprehensive emission inventory and dispersion modeling framework encompassing multiple industrial sources and pollutants. The results emphasize the critical role of diverse industrial activities in air quality degradation and offer a stronger scientific foundation for designing targeted emission control and mitigation strategies.