Determination of physico-mechanical properties of African mesquite (Prosopis africana) seeds for the design and development of processing machines

The physico-mechanical properties of African Mesquite seeds were investigated for the purpose of designing and developing a suitable equipment necessary for processing the seeds of this biomaterial. The physical properties were determined at the moisture content of 13% dry basis while the mechanical properties were determined at different moisture contents of 13%, 16%, 18% and 21% dry basis. The mean seed length, width and thickness were found to be 9.98, 6.80 and 4.66 mm, respectively. The average arithmetic and geometric mean diameters were 7.26 and 6.82 mm, respectively. The mean surface area, projected area and volume were 149.27 mm2, 58.16 mm2 and 175.69 mm3, respectively. The average roundness, sphericity and aspect ratio were 0.59, 0.63 and 0.64, respectively. The mean thousand grain mass, bulk density, true density and porosity were 335.80 g, 728.50 kg m-3, 1126.63 kg m-3 and 34.50%, respectively. The mean static angle of repose was 36.33 Degrees. The static coefficients of friction were 0.64, 0.60, 0.58, 0.63 and 0.66 on mild steel, stainless steel, glass, plastic and plywood surfaces, respectively. The results of mechanical properties determined at different moisture contents do not show any specific trend with moisture content and had maximum force at peak, force at yield and force at break of 1054.567±98.329 N, 1025.633±142.302 N and 918.900±137.238 N, respectively. There were no limitations to the report. These parameters will serve as inputs for the efficient design of processing machines for African Mesquite seeds.