P. Hemasankari, B. Dayakar Rao, E. Sai Prasanna, Vilas. A. Tonapi and R. Kailappan and C. Tara Sathyavathi
Abstract
A double head dehuller was designed and developed and its performance evaluation was done using selected minor millets of barnyard, brown top, kodo, proso and foxtail millet. The main components of the machine included hopper of 5kg capacity, a double grain crushing chamber, an outlet grain chute, blower for husk aspirator, a cyclone outlet for husk separation and a prime mover motor of 3hp power. The machine was operated both at no load and load condition for calibration and determination of capacity and efficiency. Under load condition, it was operated for 15 minutes and the husk and dehulled grain were collected separately. In double pass dehulling the hull removal is more compared to single pass dehulling, it is in the order of barnyard millet ? brown top millet ?? kodo millet ??proso millet ? foxtail millet. In double pass, the minimum dehulling percentage is 18.2% and maximum hull removal is 22.9%. Approximately in double pass, 10% more of hull removal than in single pass dehulling. Total yield ranged between 77.1 % to 81.8%. With the foxtail millet the dehulling efficiency was 64.07%, head millet recovery was 95.21%, broken grain recovery was 4.79%, dehuller performance index was 61, capacity of the double head dehuller is 96.4kg/h and husk recovery is 31.12%. With the barn - yard millet, the dehulling efficiency was 38.27%, head grain recovery was 88.98%, broken grain recovery was 11.02%, dehuller performance index was 34.05%, capacity was 74kg/h and husk recovered is 51.35%. Three replications for both single pass and double pass dehulling were made separately and the average values were taken. Then the values were tested for its statistical significance using SPSS software and it was found to be significant at 5% level of significance (p?0.05). The statistical analysis was done using SPSS 16.0 software.