Optimizing the Pyrolysis Process and Modelling the Calorific Value of Sawdust Charcoal as Composing Materials of Quality Briquettes

This study aims to optimize the pyrolysis process and build calorific value model of sawdust charcoal as composing materials of quality briquettes to fulfill the need of renewable fuels. The results showed that the calorific value of sawdust increased by 2344 Cal/g after pyrolysis. The optimum conditions of calorific value were achieved at drying temperature parameters of 60°C, pyrolysis temperature of 600°C, holding time of 120 minutes, and particle size of 100 mesh. The linearity test results between the value of R, R Square, and Adjusted R Square of the calorific value showed there is a strong correlation between drying temperature, pyrolysis temperature, holding time, and particle size. Based on validation test, the calorific value model showed that the residual normality distribution (P-value) was > 0.05 which did not form a certain pattern on the assumption of homoscedasticity, no multicollinearity (TOL > 1; V IF < 10) and the DW value was between the specified range. The model was declared valid. Based on the feasibility test model, P-value was (0.000) < α (0.05). This means the model of proper calorific value was reliable to be used to predict the sawdust charcoal calorific value.