PRODUCE CLEAN GRAIN FROM MULTI CROP THRESHER FOR SMALL SCALE FARMERS
The traditional methods of threshing of crops are inefficient, laborious, and time consuming and low out put. The existing fabricated machine was observed during preliminary testing to have low performance. In the light of the above mentioned problems, there is need to modify and testing multi-crop thresher to threshed grain at optimum speed. The threshing machine consist of the following component: Hopper, frame, beater, sieve, pulley, grain outlet and chaff outlet. The factors considered in this project work was feed rate at two levels of 2 level and were replicated twice (f1=2kg, f2=3kg) at a constant speed of 300rpm. The parameters under investigation were threshing efficiency, unthreshed efficiency, and breakage efficiency. The result revealed that themachine has a threshing efficiency, untrhreshed efficiency, and breakage efficiency of 90.1%, 9.5%, and 20.1% for feed rate 2kg and 90.9%, 9.1% and 14.11% for feed rate 3kg respectively. The time taken for 2kg and 3kg was 50.2sec and 43sec, the throughput capacity for 2kg was 143kg|hr and 3kg was 167kg|hr respectively. The feed rate of 3kg favors the machine performance.
TABLE OF CONTENTS
Title page i
Table of contents vi-ix
List of figures x
List of plates xi
List of tables’ xii
CHAPTER ONE: INTRODUCTION
1.1Background of the study1
1.2Problem statement 2
1.3 Aims and objectives 3
1.4 Justification 3
1.5 Scope of the project 4
CHAPTER TWO: LITERATURE REVIEW
2.2 Agronomy of selected crops 6
2.2.3 Guinea corn 6
2.3 Post Harvest loss on grain 7
2.4 Factors Affecting Threshing 7
2.5 Methods of Threshing 8
2.5.1 Local Methods of Threshing 8
126.96.36.199 Manual Method of grain 8
188.8.131.52 Threshing with animal or vehicle 9
184.108.40.206 Threshing with hand driven machine 9
2.5.2 Modern method of threshing 9
220.127.116.11 Em-bee power thresher 10
18.104.22.168 Midget thresher 10
22.214.171.124 FGN pedal operated thresher 11
126.96.36.199 NCAM Multi-crop thresher 11
2.6 Review on exiting work on threshing machine 11
CHAPTER THREE: MATERIALS AND METHODS
3.1 Modified Areas 14
3.2 Description of the multi-crop thresher 14
3.3 Design consideration 18
3.4 Design Analysis and calculation 18
3.4.1 Design hopper 18
3.4.2 Design for power requirement 19
3.4.3 Design for shaft 21
3.4.4 Pulley design 23
3.4.5 Belt design 24
3.4.6 Design for motor seat 24
3.4.7 Bearing selection 25
3.5 Materials selection 26
3.6 Fabrication procedure and assembly 26
3.6.1 Hopper 26
3.6.2 Frame 27
3.6.3 Threshing unit 27
3.6.4 Driven unit 27
3.6.5 Winnowing unit 27
3.6.6 Grain outlet 28
3.6.7 Shaft outlet 28
3.7 Principle of operation 28
3.8 Test Performance 28
3.8.1 Source of materials 28
3.8.2 Sample preparation 29
3.8.3 Experimental procedure 29
3.8.4 Output parameter 29
188.8.131.52 Threshing efficiency 29
184.108.40.206 Unthreshed efficiency 29
220.127.116.11 Throughput capacity 29
18.104.22.168 Determination of threshing throughput capacity 30
CHAPTER FOUR: RESULT AND DISCUSSION
4.1 Result 31
4.2 Discussion 32
CHAPTER FIVE: CONCLUSION AND RECOMMENDATION
5.1 Conclusion 33
5.2 Recommendation 34
1.1 Background of the Study
Cowpea is a grain legumes appears to have originated from west-African, very widely in Nigeria were there are many wild weedy species in both savanna and forest zone (Steel, 1992).Cowpeas are now widely distributed throughout the tropics and sub-tropics. They are grown in India, south eastern Asia, and Australia the Caribbean, southern united state and throughout the low land tropical Africa. Nigeria alone produces 61% (760000 tones) of the world total production (Irtwange 2009). Despite this figures, Nigeria continues to suffer from hunger and malnutrition. This is because the rate that of population growth is exceeded the rate of food production with a consequent decline in per capital food intake (Irtwange 2009). This call for the need to step up food production.
Grain, according to Okaka (2004) is fruit of cultivated grasses belonging to the family of monocotyledonous, gramineace. The principle cereal grain of the world includes wheat, beans, sorghum, rice and maize. Agriculture commodities are consumed as food and grains contributed to the bulk of the country’s calories and protein. The world grain is broadly used to indicate cereals and pulses. Grain however can be grown extensively for food and the fast growing agricultural based industries. They are used in either fresh form or dried form. Dried grains are preferred for industrial uses. The major processing methods used in preparing grain are dry milling wet milling and malting (Olatunji,2000).
Maize (zeamays) is cereal crops that are grown widely throughout the world in a range of agro ecological environments more maize is produced annually than any other grains. About 50 species exist and consist of different colors, texture and grain shapes and seize, white yellow and red are most common types. The white and yellow varieties are preferred by most people depending on the region maize was introduced into Africa the 1500s and since become one of African dominant food crop. The grains are rich in vitamin A, C, and E carbohydrates and essential minerals and contain 99% protein. They are also rich in dietary fiber and calories which are good source of energy (Adeokoma2001).
The major steps involves in the processing of maizeare harvesting, drying, de-husking, shelling, storage and milling. For rural framers to maximize profit from the maize, appropriate technology that suites thresher needmust be used. The processing of the agricultural product like maize into quality form not only prolong thesheff life of these product but also increase the net profit the farmer make from mechanization technology of such product.(okaka 2004). Guinea corn (sorghum) is a cereal grain that originated in Africa and is eaten throughout the world. It is especially valuable in arid terrain because of its resistance to drought, guinea corn is a nutrient rich grain that is often grand into flour to make bread, porridge and pancake including it diet offers a number of nutritional and the rapeutic benefit guinea corn contain 163calories protein, carbohydrate, fat content minerals, the one nutritional highlight of guinea corn is its mineral content. Adequate intake of iron support the transportation of oxygen in the body system and helps to promote cell growth and development of potassium helps to maintain fluid balance, and high intake in food blood pressure according to American heart association (Purseglove, 2007).
1.2 Problem Statement
Traditional threshing method do not support large- scale threshing of grains especially for commercial purposes. Locally in Nigeria the region that is the highest producer of grain like maize is the northern part of the country it was observed that the most threshing of grainwasdone by hand shelling. Hand threshing take a lot of time, even with some hand operated simple tools, it was also observed in the study area, most mechanical threshers were designed for multi grain threshing or shelling, which causes great damage to the grain seed besides breaking the maize cob to pieces the available Shellerwere locally equipped with rotating threshing drum with beater or teeth which cause damages to the seed. Besides, the costs of purchasing such thresher were high for poor rural farmer and therefore necessitated the design of low cost system that will be affordable and also increases threshing efficiency but reduce damage done to the seed (Ogunwede,2003).
1.3 Aims and objectives of the Study
The main aim of this project is to produce clean grain from multi crop thresher for small scale farmers. The specific objectives are to:
i. Design the sieve, blower and electric motor seat.
ii. To evaluate the machine in term of threshing efficiency, unthreshed efficiency, breakage efficiency and through put capacity of the machine.
1.4 Justification of the Study
The modification and performance evaluation of this project will reduce the quantity of crops blowing out of the outlet, will enhance good quality product, will reduce or eliminate drudgery compare to traditional methods of threshing and also large quantity of grain will be threshed within a very short time.
1.5The Scope of the Project
Cereals are widely cultivated in Nigeria;this study is limited to the threshing ofmaize. . Maize otherwise known as corn is important to the economy due to its wide range of users. Maize is primarily used as feed for livestock, suggesting the dependence of livestock industry or corn product.Its also used to create a variety of food and non food product such as corn meals, sweetener, corn oil, starch and ethanol which is used as cleaner burning alternative to gasoline. Factors consider was feed rate at two levels and speed at one level and were replicated twice. The parameters under investigation were threshing efficiency, unthreshed efficiency and breakage efficiency..