Seasonal Variation of CO₂, CO, and H₂S Emissions and Meteorological Influences Around a Cement Factory in Nigeria
Uzor, O. F *
Department of Integrated Science Education, Federal College of Education, Umunze, Anambra State, Nigeria.
Ogbuagu, J.O
Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria.
Arinze, R. U
Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria.
Okeke, A.P
Shanahan University Onitsha., Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Cement manufacturing is a major contributor to atmospheric emissions, especially carbon dioxide (CO₂), carbon monoxide (CO), and hydrogen sulfide (H₂S), which pose significant environmental and health risks. This study investigated the seasonal variation of CO₂, CO, and H₂S concentrations around the Dangote Cement Plant in Obajana, Nigeria, and evaluated the influence of meteorological parameters on these emissions. Ambient air samples were collected from twelve strategically selected outdoor locations during the wet (August–October) and dry (November–January) seasons. Measurements of temperature, humidity, and wind speed were also recorded to assess meteorological impacts. Results revealed that average concentrations of the sampled three pollutants were significantly higher during the dry season compared to the wet season. Elevated temperatures and reduced humidity during the dry season contributed to poor pollutant dispersion and high accumulation. CO₂ levels were primarily influenced by fuel combustion processes, while CO emissions were linked to incomplete combustion. H₂S concentrations, although generally low, were influenced by both industrial emissions and local microbial activities. Statistical analysis showed moderate to strong correlations between pollutant levels and meteorological parameters. A one-way Analysis of Variance (ANOVA) was performed separately for CO₂, CO, and H₂S using values from twelve sampling locations. The results indicated slight statistically significant difference between wet and dry season concentrations for CO₂ (F = 0.79, p = 0.3841) and CO (F = 0.51, p = 0.4838). However, H₂S levels showed a highly significant seasonal difference (F = 40.50, p < 0.0001), with consistently higher concentrations observed during the dry season. The study underscores the importance of seasonal monitoring and the need for emission control strategies to protect local air quality and public health.
Keywords: CO₂, CO, H₂S, seasonal variation, meteorology, Obajana, cement, emissions, air quality