Performance Evaluation of a Bambara Ground Nut Sheller

The shelling of pod to obtain clean seed is one of the most tedious operations in Bambara groundnut processing. As a result, it has constituted a bottle- neck to the large scale production and processing of this important proteinous crop. To overcome the problem, some physical properties of bambara groundnut pod relevant in bulk handling and processing, were investigated and a sheller using roller mechanism was designed for the crop, constructed and tested. Measurements of the physical properties showed that at the moisture content of 5 % (wb), the major, intermediate and minor diameters of Bambara groundnut pod averaged 1.89 cm, 1.57 cm and 1.44cm respectively. The true and bulk densities, porosity and one thousand-pod weight averaged 754.83 kg/m3 and 432 kg/m3, 42.77 % and 1.24 kg, respectively and the angle of repose and static coefficient of friction of the pod on steel sheet averaged 30.4o and 0.56. Results of machine performance tests showed that the moisture content, material feed rate and the interaction between them had significant effect on the quantity of shelled