Dispersion and Modeling of Gaseous Pollutants Released From 12 Hp Diesel Engines at Some Selected Sites in North Central Nigeria

Abstract

This work is aimed at quantifying the dispersion strength and environmental impacts of gaseous pollutants such as Carbon (II) oxide, Sulphur (IV) oxide and Hydrogen sulphide emitted from 12 hp Diesel powered water- cooled engine at some selected sites in North central Nigeria. A real time analysis was adopted in monitoring these sources by the use of ALTAIR Multi- gas detector. The estimated emission rates of 139.04mg/s, 4.227mg/s and 2.335mg/s were obtained for CO, SO₂ and H₂S respectively. The average monitored concentration of CO, SO₂ and H₂S for dry season at 5.0m from these sources are 4.0mg/m³, 0.185 and 0.270 respectively while that of rainy season at 5.0m from these sources are 2.272mg/m³, 0.197mg/m³ and 0.174mg/m³ respectively. The respective coefficient of regression, R2 for CO, SO₂ and H₂S for measured and modeled concentration from these sources are 0.874, 0.960 and 0.968. These depict measured and modeled CO, SO₂ and H₂S concentrations correlating highly. Based on National Ambient Air Quality Standards, the immediate microenvironments (< 5.0m) of these sources are unsafe. It is therefore recommended that exposure to these sources be grossly reduced by relevant environmental management agencies enacting environmental policies that regulate the duration of exposure to these sources so as to reduce the health impact of these emissions. Also, since these pollutants are generated in combustion, modifications to the combustion process itself by ensuring greater air to fuel mixture in the combustion chamber design can be quite effective in reducing their formation.