Characterising Emissions from Sawdust-Coal Pellets Combustion Using Ultimate Analysis Techniques

Abstract

The combustion of pure coal contributes significantly to greenhouse gas emissions (GHGs), particularly carbon dioxide (CO₂), driving global warming. This study explores the potential of enhancing coal combustion by incorporating sawdust biomass to reduce harmful emissions while maintaining thermal performance. Ultimate analyses were conducted on coal and sawdust pellets, with seven samples (Sample 1 – Sample 7) prepared using hand-mixed process in ratios of 100:0, 90:10, 80:20, 70:30, 60:40, 50:50 and 0:100 consisting of coal and sawdust respectively, and resin (the epoxy type) as binder suggesting coal-sawdust pellet possessing high mechanical strength. Calorific tests revealed calorific values ranging from 14.85 MJ/kg to 22.07 MJ/kg, demonstrating their viability as fuel sources. Emissions analysis showed CO₂ emissions were highest in Sample 1, while Sulphur dioxide (SO₂) peaked in Sample 7 exhibited the highest water vapour emissions. Nitrogen emissions generally decreased with increasing sawdust content, except for an anomaly in Sample 4. The study also revealed that the amount of carbon dioxide, sulphur dioxide, nitrogen, and water vapour emitted depends on the sawdust-coal mixed ratios. These results suggest that coal-sawdust blends can significantly reduce CO₂ emissions, aligning with Sustainable Development Goals 13.