Design and construction of a motorized paddy rice de-stoner.

Abstract

Rice is one of the major crops through which many people in Uganda earn their livelihood and in the recent past, it has gained a lot of economic importance in Uganda because it has a comparative market advantage of 1.87 over other crops especially cereals. Rice in Uganda is mainly cultivated by small scale farmers in holdings of less than 1 hectare on average and the local rice industry is faced with several challenges due to employment of rudimentary techniques during post-harvest handling which contaminate rice resulting into low physical quality, unacceptable safety and low market value which in turn make the local rice less competitive in the market place. Rice contamination is due employment of rudimentary techniques during post-harvest handling such as drying from the ground, beating rice from bare ground while threshing, manual sorting methods like hand picking. Based on the above background, the study sought to develop a motorized paddy rice de-stoner to help local farmers and rice processors improve the quality of their rice such that they can widen their market base and benefit from their hard work. The main objective was to design and construct a motorized paddy rice de-stoner and other objectives that will lead to achieving the main objective. The purpose of the study was to design and construct a motorized paddy rice de-stoner that will enable small scale fanners and rice processors produce clean quality rice to be able to compete in the current liberalized economy. The machine was constructed, of materials chosen basing on the availability on market ,ease of fabrication and design, Various methods such welding, machining, cutting among others were used during machine fabrication. Upon testing the performance of the machine, it was found to have de-stoning efficiency of 65.l % and capacity-of 130 kg/hr and economically viable. Changes like incorporating the fan and applying at least two principles in design of the machine to increase the efficiency of the machine were recommended.