PERFORMANCE EVALUATION OF A BURMIL FOR PROCESSING OF MAIZE GRITS

This paper examines the performance of a burmil using dry and wet maize at variable moisture contents and operating speeds. The moisture contents of the dry maize were 10 %, 12%, 14% and 16%. For wet experiment, the moisture contents were 22%, 25%, 30% and 35%. The operating speeds for both dry and wet experiments were 500, 550 and 600 rpm. The weight of samples were measured using an electronic weighing machine; the moistu re content was taken with a moisture - meter and the milling time recorded using a stop watch. The results showed that milling efficiency decreased with increase in moisture at all operating speeds in the two experiments. Optimum performance was recorded at 22% moisture content for wet experiment and operating speed of 500 rpm at 74% milling efficiency. While the optimum performance for dry maize was at 10% moisture content and 550 and 600rpm operating speeds at 83% milling efficiency. The particle size distr ibution increased with increase in moisture content at all the operating speeds. The finest particle was observed at 10% and 22% for both dry and wet experiments respectively. A linear relationship was observed between the operating speed and the milling e fficiency as well as the particle size distribution. It is concluded that a linear relationship therefore exists between the moisture content, operating speed, milling efficiency particle size distribution of maize grit. The results of the evaluation are t herefore recommended for the use of farmers, fabric ators and processing industries .