DEVELOPMENT OF A LOW COST RICE MILLING MACHINE

Abstract

Rice is generally considered as semi aquatic annual plant that survives as perennial in the tropics or subtropics.  The high cost of the available rice milling machine affects the production of rice in large quantity. Therefore, there is need for a low cost rice milling machine with high efficiency and reduced operating noise.  A rice milling machine was developed consisting of the feeding unit, milling unit, cleaning unit, separating unit delivery unit and the frame. The rice milling machine has a capacity of 12 kg/hr and powered by a 3hp electric motor. The process of milling involves the interaction of machine and seed for the release of grains through blown air from impeller.  The performance parameters  include, percentage of broken rice, milling efficiency of paddy varieties, wholeness and machine efficiency which were evaluated at five different moisture content groups namely; A, 11.00-12.99%, B, 13.00-14.99%, C, 15.00-16.99%, D, 17.00-18.99% and E, 19.00-20.99%.  Four varieties of paddy, NEL-42, NE 2, F55 and OFADA were used. The highest milling efficiency of 64 % was obtained for all varieties of paddy at A. The low percentage of broken rice and milling efficiency of 64% for paddy variety NEL-42 proved the effectiveness of the machine.