Design, Development and Performance Evaluations of Engine Operated Groundnut Sheller

Abstract

Groundnut is one of the largely produced oilseed crops in Ethiopia. It generates significant financial income for various householders in Ethiopia, as well as foreign exchange. Even though, groundnut is the source of income and its capacity to generate household income is constrained due to the lack of appropriate shelling machine. Groundnut shelling is a fundamental process in post-harvest management. Traditionally farmers shell the groundnut with their hands and separate the pods from its kernels. This method of shelling groundnut pods requires high man-hour, drudgery to workers, has low output and it does not fulfill the market demand. To address these problems an engine operated groundnut sheller was developed. The main components of the machine are, the hopper, frame, shelling cylinder, concave, bellowers, kernels outlet, and power train components. Machine parts design was done with CATIA V5. The shelling operation is achieved by rotational motion of drum fitted with beaters flat belt in its periphery above the stationary concave grid which results in removal of kernel from pods. Some physical and mechanical properties of the pods and kernels, relevant to the design of the sheller, were studied. A randomized complete block design was used to evaluate the machine's performance at three levels of drum speeds and three levels of concave clearance with three replications, while grain moisture content was kept constant. The collected data were analyzed using SPSS 25 statistical software. The performance results revealed that as the cylinder speed increased, the shelling efficiency, shelling capacity, and scatter loss increased but the unshelled pod's percentage reduced. As cylinder speed and blower speed increased the cleaning efficiency and the blower loss increased. The optimum operating condition for the sheller was found to be at 170 rpm cylinder speed and 892 rpm blower speed, with total shelling efficiency of 96.25% and 94.44%, cleaning efficiency of 94.80% and 93.01%, grain loss of 0.15% and 0.20%, the throughput capacity of 308kg/hr and 282.61kg/hr for Burree and Babile varieties respectively, at 16 mm concave clearance and moisture content of 7.2% (d.b). The developed machine has good performance in all aspects with easy operation and comfort in the working environment. From the performance indices of the shelling machine, the sheller is recommended for groundnut producers and industries for both Burree and Babile groundnut variety.Groundnut Is One Of The Largely Produced Oilseed Crops In Ethiopia. It Generates Significant Financial Income For Various Householders In Ethiopia, As Well As Foreign Exchange. Even Though, Groundnut Is The Source Of Income And Its Capacity To Generate Household Income Is Constrained Due To The Lack Of Appropriate Shelling Machine. Groundnut Shelling Is A Fundamental Process In Post-Harvest Management. Traditionally Farmers Shell The Groundnut With Their Hands And Separate The Pods From Its Kernels. This Method Of Shelling Groundnut Pods Requires High Man-Hour, Drudgery To Workers, Has Low Output And It Does Not Fulfill The Market Demand. To Address These Problems An Engine Operated Groundnut Sheller Was Developed. The Main Components Of The Machine Are, The Hopper, Frame, Shelling Cylinder, Concave, Bellowers, Kernels Outlet, And Power Train Components. Machine Parts Design Was Done With Catia V5. The Shelling Operation Is Achieved By Rotational Motion Of Drum Fitted With Beaters Flat Belt In Its Periphery Above The Stationary Concave Grid Which Results In Removal Of Kernel From Pods. Some Physical And Mechanical Properties Of The Pods And Kernels, Relevant To The Design Of The Sheller, Were Studied. A Randomized Complete Block Design Was Used To Evaluate The Machine's Performance At Three Levels Of Drum Speeds And Three Levels Of Concave Clearance With Three Replications, While Grain Moisture Content Was Kept Constant. The Collected Data Were Analyzed Using Spss 25 Statistical Software. The Performance Results Revealed That As The Cylinder Speed Increased, The Shelling Efficiency, Shelling Capacity, And Scatter Loss Increased But The Unshelled Pod's Percentage Reduced. As Cylinder Speed And Blower Speed Increased The Cleaning Efficiency And The Blower Loss Increased. The Optimum Operating Condition For The Sheller Was Found To Be At 170 Rpm Cylinder Speed And 892 Rpm Blower Speed, With Total Shelling Efficiency Of 96.25% And 94.44%, Cleaning Efficiency Of 94.80% And 93.01%, Grain Loss Of 0.15% And 0.20%, The Throughput Capacity Of 308kg/Hr And 282.61kg/Hr For Burree And Babile Varieties Respectively, At 16 Mm Concave Clearance And Moisture Content Of 7.2% (D.B). The Developed Machine Has Good Performance In All Aspects With Easy Operation And Comfort In The Working Environment. From The Performance Indices Of The Shelling Machine, The Sheller Is Recommended For Groundnut Producers And Industries For Both Burree And Babile Groundnut Variety.