An improved inclined kernel and shell separating machine was developed based on the principle of angle of repose and factors influencing the separation technique investigated. The difference in frictional characteristics of the kernel and shell was exploited in the design and the developed machine was evaluated for separating efficiency using the roller speed, feeding point, and surface roughness of the inclined belt as determining factors. A predetermined angle of 19o, above angle of repose of kernel but below that of shell was used for the inclined surface enabling free fall of kernel. Results from the evaluation revealed that maximum separating efficiency of 97% was attained at optimal settings of roller speed of 58.3rpm, feeding distance of 500mm along the plane and using fabric material surface (Rug). Hence, the three factors were critical in improving the separating efficiency of the adopted technique for high kernel recovery and thereby enhancing the quality of palm kernel oil production with insignificant 3% shell contaminations.
Key words: Angle of repose, palm kernel/shell separation, roller speed, feeding distance, frictional surface.
|
