Emission inventory of gaseous air pollutants and particulate matter from industrial point sources in Ogun State, Nigeria

This study focuses on both particulate matter (PM) and gaseous pollutants emission characterization from boiler’s and industrial stacks. The study looks into the emissions profiles of several boiler types that are frequently utilised in industrial settings including biomass, natural gas, diesel, oil, and coal-fired boilers. The USEPA Method 5 was employed for measurement of PM while the characterization of gaseous pollutants such as carbon monoxide (CO), Oxide of nitrogen (NOx), hydrocarbon (HC), volatile organic compounds (VOCs) was done using E8500 Industrial Combustion Analyzer. Additionally, the Emission Factors of identified pollutants were also developed in the study. The average concentration was between 29.45 – 530.04 mg/m 3 , 13.50 – 1948.67 mg/m 3 , 0.0 – 742.23 mg/m 3 , 103.62 – 450.81 mg/m 3 , 0.0 – 906.73 mg/m 3 for TPM, HC, CO, NO x , VOCs respectively for the natural gas fired boiler. However, for the diesel fired boilers, the concentration ranged 29.45 – 515.31 mg/m 3 for TPM, 46.49 - 359.92 mg/m 3 for HC, 2.74 – 332.49 mg/m 3 for CO, 72.53 -524.40 mg/m 3 for NO x and 0.00 – 3.97 mg/m 3 for VOCs. The mean values of PM were 588.93, 176.68, 235.57 and 309.19 mg/m 3 for firewood, charcoal, isothermic oil and black oil respectively. The mean concentration of identified pollutants from all the production stacks was 44.17 – 485.87 mg/m 3 , 79.47 - 1021.27 mg/m 3 , 82.45 – 2324.75 mg/m 3 , 35.75 - 967.93 mg/m 3 for PM, HC, CO and NO x respectively and their corresponding mean values were 171.16 mg/m 3 , 529.19 mg/m 3 , 645.57 mg/m 3 , 476.91 mg/m 3 . The measured concentrations were compared with point source air quality standard in Nigeria (FEPA, 1991) to determine the impact of boilers and production stacks on host environment. The study revealed that there is excessive emission of HC and CO from industrial boilers and production stacks, thus calling for improvement in measures on emission control, use of cleaner fuel and stringency in regulatory measures with a view to protecting the environment and public health.