Energy consumption Pattern as affected by machine operating parameters in mechanically expressing oil from Pentaclethra macrophylla: Modeling and optimization

Abstract

this study investigated the influence of operating speed, applied pressure and feed rate on the Specific Mechanical Energy Consumption (SMEC) of an expeller while extracting oil from Pentaclethra macrophylla kernels. Independent variables included speed (15, 30, 45, 60 and 75 rpm) which was varied using pulley arrangement, pressure (5, 10, 15, 20 and 25 MPa) which was varied through adjustment the worm-shaft distance of the expeller, and feed rate (100, 200, 300, 400 and 500 g/min) while the dependent variable was SMEC. All parameters and levels were chosen based on preliminary investigations and literature reports for similar oil crop. Response surface methodology was used for analysis, modeling and optimization. The predicted and experimental values were compared in validating the model. The SMEC was minimized and independent variables were set at ranges of levels used for experimentation in order to optimize the process. Optimum SMEC of 0.053 kW h/kg was obtained at 45rpm, 8 MPa applied pressure and 327 g/min feed rate with a desirability of 0.99. The quadratic model predicting the SMEC showed that speed and pressure had significant influence on SMEC and also showed an excellent agreement between the variable due to low standard error and deviations between calculated and predicted values.

Keywords

• Speed
• Applied pressure
• Feed rate
• Specific mechanical energy consumption
• Oil extraction