Application of plackett-burman design on screening the factors affecting torrefaction of palm kernel shell

Abstract

Plackett - Burman design (PBD) is used for screening important factors. In a PBD, the experiments are generated at various combinations of low and high values of the process variables and analyzed for their effect on the process. The purpose of this investigation was to study the statistical analysis for screening the factors affecting torrefaction of palm kernel shell (PKS). PBD was applied for screening effect of temperature, time, oxygen content, heating rate and biomass size to calorific value of torrefied PKS. The significant parameters were selected based on the analysis of variance (ANOVA) results. The results shown that the temperature and oxygen content were significant factors for the torrefaction of PKS which the respectability of received model was proved with high correlation coefficient. The result of 3D surface plots was shown that the temperature was the highest effect compared to other factors which calorific value were increased when the temperature increases. The diagnostic plots were examined for the model decency which the obtained linear model was quite good for prediction of calorific value of torrefied PKS. It was summarized that the predicted values by statistical model were close to experimental values.