Biochar yield prediction using response surface methodology: effect of fixed carbon and pyrolysis operating conditions

Abstract Generating value from wastes via pyrolysis has been increasingly researched in recent times. Biochar is a versatile product with yields based on many process parameters, including feedstock type and particle size, operating conditions such as reactor, heating rate, residence time, reaction temperature. The heterogeneous nature of waste biomass creates challenges controlling the pyrolysis’ selectivity. Intensive time-consuming experimental studies are often required to determine distribution for each unique feedstock. Alternatively, prediction models that learn wide range existing data may provide insight into potential different sources. Several advanced exist literature which can predict yield biochar subsequent products However, these do not consider combined effect characteristics yield, considered decisive factor formation. As such, objective this study develop model biomass’ fixed carbon content (14–22%), temperature (350–750 °C), rate (5–10 °C/min) using response surface methodology. Biomasses, date stones, spent coffee grounds, cow manure have used design Box-Behnken experiment three factors response. An empirical equation developed statistically significant quadratic produce optimized high accuracy. discussed 3D diagnostic plots conducted validation experiments confirm applicability model. significantly affected by temperature, confirms accuracy quantification. be easily applied further flow modeling pyrolysis, only relying proximate feed analysis, rate.