Development of a Wet Yellow Maize Mash Sieving Machine

Abstract

Wet sieving is still a manual operation in tropical crop processing. It is a time consuming operation. Most of the existing wet sieving machines are available in large scale industries and they are too sophisticated to operate and maintain by local processors. In this study, a low – cost simple prototype wet sieving machine was designed, fabricated and tested using locally available materials to solve the problems associated with sieving of wet agricultural products in Nigeria. The machine consists of a sieving compartment operated by a crank through vibratory and reciprocating mechanism obtained with the use of an eccentric cam and springs arrangement, collecting trays and outlets. The test considered feed rate Q, at three levels 0.085Kg/s, 0.17Kg/s and 0.43Kg/s and concentration X, at three levels 12.23%, 14.44%, 22.77%. The study showed that the machine performance coefficients and sieving capacity decreased with increasing concentration and feed rate. Higher performance and sieving capacity was achieved at a treatment combination X2Q2 where the performance coefficients and sieving capacity are 76.42% and 7.5 x 103 Kg/s respectively. A unit of the machine costs N5, 850.00 as at April 2006. It requires little maintenance.