ABSTRACT
This research centers on the design, development and testing of a motorized juice extractor fabricated using locally-available materials. The machine is made essentially of two basic compartments: the chopping compartment and the juice extracting compartment. Other components include feeding hoppers, top cover, auger conveyor housed in a cylindrical barrel, juice sieve, juice collector, waste outlet, transmission belt, main frame, pulleys and bearings. In operation, fruits introduced into the chopping compartment via the first hopper are chopped/sliced and passed into the extracting compartment via a second hopper. The auger conveys, crushes, presses and squeezes the fruits to extract the juice. The juice extracted is filtered through the juice sieve into juice collector while the residual waste is discharged through waste outlet. When tested for freshly harvested pineapple, ginger and orange fruits, results show that the average juice yield for pineapple, orange and ginger were respectively 74 %, 72 % and 34 %; juice extraction efficiencies were respectively 84 %, 80 % and 71 %; and juice extraction losses were respectively 18 %, 16 % and 9 % at optimum machine speed of 335 rpm for pineapple and oranges, and 476 rpm for ginger. Powered by a 3hp electric motor, the machine has a capacity to process 30 litres/hr of oranges, 32 litres/hr of pineapples and 24 litres/hr of ginger and the machine costs of about N54,600, hence it is affordable for small-scale farmers.
TABLE OF CONTENTS
CHAPTER ONE
1.0 Introduction
1.1 Background of the study
1.2 Statement of the problem
1.3 The present work
1.4 Aim and objectives
1.5 Significance of the study
1.6 Justification
1.7 Scope of study
CHAPTER TWO
2.0 Literature Review
2.1 Introduction
2.2 Nutritional Value of fruits
2.3 Fruit juice extraction
2.3.1 Efficiency of extraction
2.3.2 Traditional method of fruit juice extraction
2.4 Agricultural fruits available for juice extraction
2.4.1 Ginger rhizome
2.4.2 Pineapple fruit
2.4.3 Orange fruit
2.5 Review of previous works
CHAPTER THREE
3.0 Materials and Methods
3.1 Introduction
3.2 Description of the motorized juice extractor
3.3 Assembly and working principle of the juice extractor
3.4 Design considerations/Specifications
3.4.1 Materials selection
3.4.2 Description of the components of the juice extractor
3.4.2.1 Feed hoppers
3.4.2.2 The chopping compartment
3.4.2.3 Extracting compartment
3.4.2.4 The frame and stand
3.4.2.5 The outlet compartment
3.4.2.6 The power unit
3.5 Design theories
3.5.1 Power requirement of the chopping unit
3.5.2 Peripheral speed of the blade shaft
3.5.3 Design of the number of blades on shaft
3.5.4 Volume of the feed hoppers
3.5.5 Design of the screw conveyor of the extracting unit
3.5.6 Design of the load that can be lifted by the auger
3.5.7 Design of the pressing area and pressure of auger
3.5.8 Design of the pressure of the barrel
3.5.9 Design of the first pitch of the decreasing pitch auger
3.5.10 Design of the pitches of the decreasing pitch auger
3.5.11 Design of the theoretical capacity of the extractor
3.5.12 Design of the volumetric capacity of the extractor
3.5.13 Design of the power requirement for extraction
3.6 Design calculations
3.7 Construction processes
3.7.1 Fabrication of the machine components
3.8 Performance evaluation of the motorized juice extractor
3.8.1 Test procedure
3.9 Cost analysis of the juice extractor
CHAPTER FOUR
4.0 Results and Discussions
4.1 Results
4.1.1 Performance parameters versus operating factors using pineapple fruits
4.1.2 Performance parameters versus operating factors using orange fruit s
4.1.3 Performance parameters versus operating factors using orange ginger
4.2 Discussion of results
4.2.1 Juice yield
4.2.2 Extraction efficiency
4.2.3 Extraction losses
CHAPTER FIVE
5.0 Conclusions and Recommendations
5.1 Conclusions
5.2 Recommendations
5.3 Contributions to knowledge
REFERENCES
CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
Before the discovery of crude oil in commercial quantity in the 1970s, agriculture was the mainstay and sustaining source of the Nigerian economy. The agricultural sector contributed immensely to the gross domestic product (GDP) of the nation. The discovery of oil and the boom that resulted from the exploitation of crude oil in the 70’s inflicted a big blow on the agricultural sector as all attention was shifted to oil, leading to the neglect of this vital sector (Fasanya et al., 2013). Various programmes such as Operation Feed the Nation (OFN) of 1976 and the Green Revolution of 1979 were embarked upon to ensure that there is enough food for the ever-growing population of Nigeria. This agricultural potential was what Nigeria exploited in the pre-independence and the post-independence period prior to 1975, which gave it its leadership position internationally in the production and export of agricultural products (CBN, 2004). Well over 50 % of the country’s total export earnings came from the agricultural sector prior to the 1970s (CBN, 2004; Ndubisi et al., 2013). Furthermore, the agricultural sector accounted for about 50 % of the GDP and employed about 72 % of the labour force on average between 1960 and 1970 (CBN, 2004; Fasanya et al., 2013).
In developed countries like the USA, Germany, France, Italy, Canada and Great Britain etc., the productivity of the Agricultural sector is always on the increase. These achievements results from their high level of mechanization.
