Design of carrot washing and grading machine.

Carrot washing and grading is performed after harvesting and before transporting to the market has been done with traditional methods by farmers in Ethiopia with too tedious, much time, and labor-consuming which leads to health problems, Fertile soil erosion, discouraging for carrot production and river water pollution. The main objective of this study was to design, develop, and perform the evaluation of carrot washing and grading machine after harvesting before transporting to market that was not used for cooking purposes to alleviate the above-stated problems. During design, a power source, initial speed, and discharge capacity of the pump were considered as 50 W, 6.28 m s-1 and 0.036 L s-1 respectively based on literature reviews. Performance of this machine evaluation was carried out with Nantey variety at two levels of feeding loads 10kg and 15 kg at different drum speeds; 1.47 m s - 1, 2.20 m s-1, and 2.93 m s-1. The data was collected in both qualitative and quantitative methods. The overall mean results obtained for performance indicators in terms of time required to complete washing and grading activities, washing efficiency, grading efficiency, percentage of damage root, and throughout put capacity were recorded as 2.22 minutes, 98.70%, 92.23%, 1.21%, and 242.17 kg h-1, respectively. The results indicated that the time required of 2 to 10.88minutes, washing efficiencies of 84.87% to 98.70% or the range of the variable of drum speed between 1.47 to 2.93 m s-1 and for the range of the variable of feeding load 10-15 kg. As the speed climbed from 1.47 to 2.93 m s-1 and the feeding load rose from 10 to 15 kg, the grading efficiency increased from 72.89% to 92.23%. Each one of these machines cost $313.18. The grading unit should be adjusted to a vibration mechanism by separating it from the washing unit in a layer of the machine frame because the carrot roots have low sphericity (30%), which led to some amounts of carrot roots being erroneously graded. Additionally, it is suggested that the pedal-turning mechanism be modified to serve the dual function of generating power that may be stored during operation and used at night in order to enhance rural electrification. [ABSTRACT FROM AUTHOR]