Optimization of Process Parameters for Pellet Production from Corn Stalk Rinds Using Box–Behnken Design

Abstract

In the current study, corn stalk rinds were used as feedstock for the production of solid-fuel pellets. In an effort to comprehensively analyze the effects of different operational parameters on the physical properties of pellets, response surface methodology (RSM) was employed in conjunction with a Box–Behnken experimental design (BBD). By assessing multiple variables simultaneously and examining their interactions, BBD facilitates the development of a reliable response model that can predict how changes in independent variables will impact response variables. The recorded responses included relaxed density, mechanical durability, and compressive strength. Based on the results, greater R2 values of 0.9467, 0.8669, and 0.9196, could be, respectively, attained for the quadratic regression models. The analysis of variance revealed that all independent variables had significant effects on the responses. The optimal processing condition for the pellets was established by determining the ideal combination of operational parameters. The process entailed the choice of a particle dimension measuring 0.5 mm, a moisture level of 11.35%, the application of heat at 125.7 °C on the die, and the utilization of a molding pressure of 154.2 MPa. Based on these factors, the predicted response values were determined to be 1639.61 kg/m3 for relaxed density, 97.95% for mechanical durability, and 10.18 MPa for compressive strength. The values obtained experimentally under the optimized conditions were similar to the predicted values with a desirability value of 1.00.