Design and construction of a motorized cassava peels grating machine :

Abstract

Uganda is one of the top producers of cassava in Africa. Uganda’s annual cassava production is 3.5 million tons, grown on an estimated 0.4milion hectares (www.fao.org, Article by Kalyango Ronald), and that it is the second most important staple food after bananas. Cassava root is the third-largest source of food carbohydrates after rice and maize and it gives third highest yield of carbohydrates per cultivated area among crop plants, However, the roots are rich in calcium and vitamin C and contain a nutritionally significant quantity of thiamine, riboflavin and nicotinic acid. The products from cassava tuber processing include; Cassava flour, Cassava chips, Cassava breakfast/snack flakes, Starch, Glue, Ethanol, Cassava leaves, Fresh roots and Cassava and the by-product of cassava is cassava peels as ingredient for Animal feeds. However wet cassava peels contain high moisture content and quickly deteriorate. In addition, fresh cassava peels contain hydrocyanic acid which generates free cyanide and this calls for pounding by using a grating machine. A motorized cassava peels grating machine was designed, fabricated from Busitema university located in the eastern region of Uganda. The materials chosen were basing mainly on the cost, availability and workability. The machine attained an average efficiency of 68.3 % at feed rate of 0.046kg/s after with the different masses of cassava peels. The machine can be used in production by both medium and large-scale processors to grate cassava peels. Also, the machine is cheap and affordable in terms of power requirement, its maximum power requirement is 3HP. The machine has the NPV of 352, 946UGX and the payback period of 1.2yearsmaking viable with the initial investment of1,145,755UGX having the selvage value of 561,419.95UGX, hence makes the machine to attract the processors of the cassava and cassava peels. The cassava peels grating machine comprises of the process system and the support system and these include; the feed hopper, crusher drum, main rotating shaft, cylindrical regulatory plate, main frame and power unit.