Organo-Mineral Modification of Coal-Biomass Briquettes for Enhanced Performance and Emission Reduction

This study investigates the influence of modified organo-mineral additives on the microstructure, calorific value, mechanical strength, and emission characteristics of coal-biomass briquettes. Experimental work demonstrated that incorporating up to 20% of a thermally treated bentonite-polysaccharide composite significantly reduced total porosity from 58.4 to 11.4% and increased density from 910 to 1070 kg/m³. The calorific value increased by approximately 14%, reaching 22.2 MJ/kg. Mechanical strength improved significantly, with maximum compression load increasing from 580 to 1150 N. Emissions of CO and CO₂ during thermal decomposition decreased by up to 45%, while volatile organic compounds were nearly halved compared to reference briquettes. The kinetic analysis revealed that the activation energy of thermal degradation grew from 136 to 181 kJ/mol, indicating enhanced thermal stability. Additionally, the briquettes demonstrated improved resistance to moisture and abrasion, highlighting their potential for safer storage and transportation. Overall, the results validated the effectiveness of combining coal waste, biomass, and functionalized mineral additives to produce solid fuels with predictable performance and reduced environmental impact.