Design, Fabrication And Performance Evaluation Of Pedal Operated Groundnut Decorticator
In this study, we present the development, construction, and assessment of a pedal-operated groundnut decorticator, aimed at enhancing the efficiency and productivity of groundnut processing in agricultural settings. The design integrates innovative mechanisms to facilitate the removal of groundnut shells, optimizing the decorticating process for small-scale operations. Fabrication involved the utilization of locally available materials and components to ensure cost-effectiveness and accessibility. Performance evaluation encompasses rigorous testing to assess the decorticator’s throughput, shell removal efficiency, and ergonomic suitability for operators. The results demonstrate significant improvements in decorticating speed and effectiveness compared to traditional manual methods, highlighting the potential of the pedal-operated decorticator to enhance groundnut processing efficiency in rural and resource-limited environments.
Shelling of groundnut pods (Arachis hypegea) by hand is tedious, laborious and unhygienic with low efficiencies. As a result farmer get low income due to amount of broken kernels and a lot of time is lost in the tedious shelling operation. To overcome this problem, pertinent parameters that influence shelling efficiency of pedal operated groundnut decorticator were identified. Pedal operated decorticator were designed and fabricated with chain and sprocket of bicycle and aluminum spike tooth is used and evaluation was done in the department of Agricultural and Bio-Environmental Engineering Technology, Kwara State Polytechnic, Ilorin because it was affordable and locally fabricated. A rotary motion mechanism was employed to drive the decorticating drum while concave screen was fixed. The selection of the screen aperture was based on the size and shape of the groundnut seed. The factors considered in this project work were feed rate and operators characteristics (height, weight and knuckle lengths). The evaluation of machine was conducted while time was taken for each tests. The result of the pedal operated groundnut decorticator revealed that operator III has the maximum shelling efficiency of 65% was achieved at 9minutes, 16 seconds and breakage of 9% and throughput capacity of 15.3kg/hr. Operator II was the optimum shelling efficiency of 56% at 12 minutes 44 seconds and breakage of 8% and throughput capacity of 14kg/hr. Operator I has the minimum shelling efficiency of 47% at 11 minutes 44 seconds and breakage of 16% and throughput capacity of 15kg/hr. The total amount used for the fabrication of the pedal operated groundnut decorticator was totaled to Ninety-two Thousand and Seven Hundred Naira only (N92,700.00). The result of the fabricator implies that the characteristics of Operator III is recommended to farmers who shell for seed can now obtained more seed shelled with low breakage and will get more income.
Cover Page
Title Page
Certification
Dedication
Acknowledgements
Abstract
Table of Contents
List of Tables
List of Figures
List of Plates
CHAPTER ONE:
INTRODUCTION 1
1.1 Background to the Study 1
1.2 Statement of the Problems 2
1.3 Objective of the Project 2
1.4 Justification of the Project 3
1.5 Scope of the Study 3
CHAPTER TWO:
LITERATURE REVIEW 4
2.1 Physical Properties of Groundnut 4
2.1.1 Determination of Size 4
2.1.2 Determination of Coefficient of Friction 5
2.1.3 Determination of Moisture Content 5
2.1.4 Angle of Repose 6
2.1.5 Porosity 6
2.1.6 Surface Area 6
2.2 History of Groundnut in Nigeria 6
2.3 Agronomy of Groundnut 7
2.4 Post Harvest Losses of Groundnut Seeds 8
2.5 Economic Importance of Groundnut Seed 9
2.6 Factor Affecting Shelling Operation 11
2.6.1 Cylinder-Concave Clearance 11
2.6.2 Sieve Shake 12
2.7 Description of some Threshing Equipment 12
2.7.1 Maize Sheller 12
2.7.2 Maize Dehusker-cum Sheller: 13
2.7.3: Hand Maize Sheller 13
2.7.4 Groundnut Striper 14
2.7.5: Groundnut Thresher 15
2.7.6: Groundnut Decorticator Manually Operated 16
2.7.7 Power Operated Groundnut Decorticator 17
2.7.8 Pedal Operated Thresher (Paddy Thresher): 18
2.8 Terminology Related to Thresher 18
2.8.1 Feed Rate 18
2.8.2 Clean Grain 19
2.8.3 Concave Clearance 19
2.8.4 Cleaning Efficiency 19
2.8.5 Threshing Efficiency 19
2.9 Review of Existing work 19
CHAPTER THREE:
MATERIAL AND METHODS
3.1 Physical Properties of Biological Materials 23
3.1.1 Sample Preparation 23
3.1.2 Determination of Size and Shape 24
3.1.3 Determination of Moisture Content 24
3.1.4 Determination of Mass, Volume and Density 25
3.1.5 Determination of Coefficient of Static Friction 25
3.1.6 Determination of Angle of Repose 25
3.2 Description of the Groundnut Pedal Operated Machine 26
3.3 Design Consideration 28
3.4 Design Calculation and Analysis 28
3.4.1 Design for Hopper 28
3.4.2. Design for Decorticating Unit 29
3.4.3 Design of Chain Drive 32
3.4.3.1 Determination of Chain Length between the Pedal and Idler Shaft 32
3.4.3.2 Determination of Chain Length Between the Idler Shaft and Decorticating Shaft
3.4.3.3 Determination of Chain Length Between the Idler Shaft and Blower Shaft 33
3.5 Material Selection 34
3.6 Fabrication Procedure and Assembly 34
3.6.1 Fabrication of Main Frame 34
3.6.2 Fabrication of Hopper 35
3.6.3 Fabrication of Bicycle Pedal and Chain Drive 35
3.6.4 Fabrication of Decorticating Drum 35
3.6.5 Decorticating Screen 35
3.6.6 Operator Seat 36
3.6.7 Aluminum Spike Tooth 36
3.7 Principle of Operation of the Machine 36
3.8 Cost Analysis 37
3.9 Performance Evaluation 38
3.9.1 Sourcing of Experimental Material 38
3.9.2 Sample Preparation 38
3.9.3 Experimental Procedure 38
3.9.4 Instrumentation Used for the Experiment 39
3.9.5 Design Layout 42
3.9.6 Output Parameter 42
CHAPTER FOUR:
RESULTS AND DISCUSSION
4.0 Results And Discussion 45
4.1 Results 45
4.2. Discussion 46
4.2.1 Physical Properties of Groundnut Pods 46
4.2.2 Effect of Operator Parameter Threshing Efficiency 47
CHAPTER FIVE:
CONCLUSIONS AND RECOMMENDATIONS
5.1 Conclusions 48
5.2 Recommendations 48
References 49
Appendix A 52
Appendix B 59
INTRODUCTION
1.1 Background to the Study
Groundnut (Arachis hypogaea) is a species in the legume or beans family (AshishandHanda, 2014; Atiku et al., 2014). It was first cultivated in Peru. Its seed contain about 63% carbohydrate, 19% protein and 6.5% oil. Groundnuts are grown in tropical and subtropical climate regions and warmer parts of temperature regions and it is low growing annual plant and has a variety of uses. Prior to its usage however groundnut need to undergo preprocessing which include drying and shelling. Removing of kernels from the pod is generally referred to as shelling or “decorticating” (Maduako et al., 2006). In Nigeria groundnut is mainly decorticate by hands (traditional method). This method is not hygienic as dirt from hands and mouth could pose health risk from the nuts. (FAO. 2001).
Shelling is a fundamental step in groundnut processing as it allows the kernel and hull to be used as well as other post harvesting technologies to take place such as oil extraction or in hull briquetting (Pradhanaet al., 2010). Shelling is usually carried out on the farm just before the farmer sells his product for the following reasons: Kernel do not store as well as nuts in the shell and groundnuts in the shell are fifty per cent heavier than kernels alone and therefore costlier to transport. Shelling can generally be done by hand or machine. Hand shelling is the process in which the pod is pressed between the thumb and first finger so that the kernel is released. In mechanization now we use large and smaller machinery for groundnut shelling. These machines are used in industries where large production is required. There are different methods of shelling and different machines have been fabricated and used to shell wide variety of crops under different conditions (Nyeaanga et al., 2003., Atiku et al., 2004; Gitau et al., 2013; andMaduakoet al., 2006). The peasant farmer cannot afford this machine because they are too costly and complex in operation and maintenance. Also the operator had to be trained and spare part imported. These factor increase the overall cost production which does not make any economic sense to the farmer.
1.2 Statement of the Problems
Research shows that groundnut has an inherent poor storage life, if not threshed after harvesting unlike some other crops, but in threshed forms, it can be stored for a very long period of time (Onuoha2010). Therefore, to overcome the problem associated with manual threshing and quick rate of insect infestation after harvesting, the development of groundnut decorticating machine is of paramount. Traditionally the seeds are left in the pods which would then be stored in a pot and would only be shelled when they are needed for cooking (Ngugi, 2007), shelling is one by hand or beating with a short stick or pestle and mortar, followed by winnowing (KaulandEgbo,1985). The constraints such as fatigue, high time energy inputs and inefficiency in manual shelling of groundnut led to design and fabrication of pedal operated groundnut Sheller that will go a long way in solving the problem of rural farmers that are engage in groundnut production at small and medium scale level.
1.3 Objective of the Project
The main objective of the project is to design and fabricate a pedal operated groundnut decorticator that will remove and separate the groundnut seed from the hull for domestic and industrial uses.
The Specific Objectives are to:
i) determine the physical properties of groundnut seed in relation to the design of pedal operated ground decorticator.
ii) design and fabricate a pedal operated groundnut decorticator
iii) evaluate the performance of the decorticator in terms of decorticating. Efficiency, percentage of breakage, percentage of shelled seed throughput capacity.
1.4 Justification of the Project
Due to high lose that are recorded due to lack of adequate power supply, these are expected to be achieve at the end of the project.We can save the time and money by using pedal operated groundnut decorticator, limited number of labour will be required, groundnut will be available for domestic and industrial use. The fabrication of the machine will encourage the farmers to grow more groundnuts.
The machine would overcome the traditional method by reducing wastage due to crack or crushed groundnut, to increase the efficiency, to reduce the hard work and to reduced time to shell the groundnut, to develop a low cost machine which can be used by farmer to convert their semi-finished (shell groundnut) into finished product (groundnut) and it satisfies the need of village people to earn more money.
1.5 Scope of the Study
Groundnut is the sixth most important oil seed crop in the world and is widely cultivated in Nigeria. The project work is limited to groundnut seed. The variable factors to be considered in this study were feed rate and characteristics of the operator (weight, height and knuckle length).
Pedal Operated Groundnut Decorticator:
A pedal-operated groundnut decorticator is a simple and manually operated machine used for removing the outer shell or husk from groundnuts (also known as peanuts). This device is commonly used in rural or small-scale agricultural settings where access to electricity or more advanced machinery is limited. The decortication process is essential for obtaining edible groundnut kernels or seeds.
Here’s a basic overview of how a pedal-operated groundnut decorticator typically works:
- Machine Structure: The machine consists of a frame or base on which all the components are mounted. It often has a seat for the operator to sit on, and pedals for their feet to operate.
- Feeding Mechanism: Groundnuts are loaded into a hopper or a feeding mechanism at the top of the machine. The hopper guides the nuts to the decortication area.
- Decortication Mechanism: The heart of the machine is the decortication mechanism, which is usually made up of rollers or grinding plates. These rollers or plates rotate when the operator pedals, and the groundnuts are passed between them.
- Husk Separation: As the groundnuts are fed between the rollers or plates, the friction and pressure exerted by the rotating components help to break the outer husk or shell. The husk is typically lighter and more brittle than the seeds.
- Collection of Seeds: The decorticated groundnut seeds or kernels fall out of the machine, typically onto a collecting tray or container, while the husks are separated and discarded.
- Pedal Operation: The operator sits on the seat and uses their feet to pedal, providing the power needed to drive the decortication mechanism. The pedal-operated design makes it a manual and low-tech solution suitable for areas with limited access to electricity.
Advantages of a pedal-operated groundnut decorticator:
- Low Cost: These machines are relatively inexpensive to manufacture and operate, making them accessible to small-scale farmers and rural communities.
- Manpower Utilization: They utilize human power effectively and can be operated by local workers without the need for specialized training.
- Energy Efficient: Since they don’t rely on electricity or fuel, they are environmentally friendly and energy-efficient.
- Suitable for Rural Areas: They are well-suited for use in rural areas where access to modern machinery is limited.
- Improves Efficiency: Decortication machines help streamline the groundnut processing process, reducing the time and effort required to shell groundnuts manually.
While pedal-operated groundnut decorticators are effective for small-scale processing, larger-scale operations may require motorized or automated decortication equipment to meet production demands. These larger machines are capable of processing larger quantities of groundnuts more quickly.