INVESTIGATION OF RELAXED DENSITY AND IMPACT RESISTANCE OF RICE HUSK AND GROUNDNUT SHELL ON HYBRID BRIQUETTES

Abstract The investigation of relaxed density and impact resistance of rice husk and groundnut shellbased hybrid briquettes was conducted to evaluate the potential of these agricultural waste materials in enhancing the properties of briquettes for fuel applications. This study investigates the relaxed density and impact resistance of hybrid briquettes made from rice husk and groundnut shells, with an emphasis on statistical modeling and optimization. Using Design Expert software, various models (Linear, 2FI, Quadratic, and Cubic) were evaluated for predictive accuracy. The Quadratic model provided a balanced fit for relaxed density (R² = 0.7022), indicating significant nonlinear effects of compaction pressure and its interactions with treatment levels. However, poor predictive accuracy was noted for impact resistance across all models, suggesting the need for further refinements or additional variables. Normal probability plots validated the residuals' normality, confirming the reliability of parametric tests. Optimization results identified ideal compaction pressure, particle size, and treatment levels, achieving a desirability score of 0.853. These findings support the feasibility of using rice husk and groundnut shells to produce consistent hybrid briquettes, with implications for quality control and material optimization in biofuel production. The results revealed that the hybrid briquettes produced from rice husk and groundnut shell showed promising characteristics, with an optimal binder content of 10% significantly improving both the relaxed density and impact resistance.