ABSTRACT

Four sweat boxes were constructed using wooden material (IO x 10 x 35) (LWH) and hoisted 4 electric bulbs of 100, 200, 300 and 400 watts respectively on the boxes. Cocoa been sorted into four different grain sizes of coca into samples (A, B, C, D), then subjected to drying until 13- 14% moisture content was reached. In another instance two hundred grams of the various sample sizes were also dried in oven, solar dryer and sun. During the drying, the moisture loss was detennined; humidity and temperature were also monitored hourly. The moisture loss was significant among the cocoa sizes and ranged between 86.50 g- 114 g for 400 watts, the moisture loss was least 49.9 g in sample B for 100 watts heat source. The least j effective method was oven drying which bad 13.17 g moisture loss after 17 hours drying. The humidity was highest in the oven at 74.94% while the least was 61.94% on the solar drier 400 and 300 watts sweat boxes was the most effective in terms of time-economy at 6 hours. Sweat boxes can effectively be used during rainy season for cocoa drying.

TABLE OF CONTENT

Title PageCertification

Dedication

Acknowledgements- -

Table of contents

List of tables- -

List of figure- -

Abstract -

CHAPTER ONE: Introduction

1.0 l3ackground -

1.1 Statement of Problemii

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VII

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X

l.2 Justification1.3 Objective of Study -

CHAPTER TWO: Literature Review

2.0 Overview of the Study- -

2.1 Cocoa J>rocessing--

2.1. I Fcrrncnlalion (Curing)- -

2.2 Drying2.3 Factors Affecting the Rate of Drying Cocoa Beans2.3.1 Particle Sizes EfTcct - -

2.3.2 Moisture Content Effect2.3.3 Heal Source Effect -

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2.3.4 Thermodynamic Properties Of Drying Environment - -

CHAPTER TIIREE: Materials and Methods

3.1 Material and Methods -

3. I. I Description of Sweat Box-

:t 1.2 Projected Swenl 3ox- -

3.1.3 Design Consideration3.2 Experimental Procedure3.3 Data Analyst's--

CHAPTER FOUR:

4.0 Result and DiscussionCHAPTER FIVE

5.0 Conclusion and Recommendation5.1 Conclusion5.2 Recommendation--

REFERENCES

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LIST OF TABLES

Table 3.1 The grads of the different particle sizes- 25

Table 4.1 Moisture loss, change in temperature, average rclalive humidity

and drying lime or cocoa bean (sample A)- 28

Table 4.2 Comparison or drying efficiency of deferent drying method with

respect to cocoa bean (sample B)- 34

Table 4.3 Comparison of drying efficiency of deferent drying method with

respect to cocoa bean (sample C)- 40

Table 4.4 Comparison or drying cniciency of deferent drying method with

respect to cocoa bean (sample D)- 46

Table 4.5: Summary of the efficiency of the sweating boxes- 52

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LIST OF FIGURES

Figure 2.1 ~ A diagrammatic illustration of heat transfer on seed plants- -

figure 3.1: orlhogrnphic projection of the sweat boxFigure 3.2: the exploded isometric view of the sweat boxesFigure 3.3: The components parts of the sweat box14

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Figure 4.1:

Figure 4.2:

Figure 4.3:

figure 4.4:

Figure 4.5:

Figure 4.6:

Figure 4.7:

Figure 4.8:

Surface plots showing the effect of temperature and

humidity on the drying of sample A of cocoa beans--

Surface plots showing the effect of temperature and

time on the drying of sample A of cocoa beansSurface plots showing the effect of humidity and

time on the drying of sample A of cocoa beansRate of moisture loss by sample --A at different power

Ratings of the sweating Box- -

Surface plots showing the effect of temperature and humidity on the

drying of sample B of cocoa bcans- -

Surface plots showing the effect of temperature and

time on the drying of sample B of cocoa beansSurface plots showing the effect of humidity and

time on the drying of sample B of cocoa beansRate of moisture loss by sample -B with time di ffercnl power

ratings of the sweat box30

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Figure 4.9: Surface plots showing the effect of temperature and humidity on

the drying of sample C of cocoa beans- 42

Figure 4.10: surface plots showing the effect of temperature and time on the

drying of sample C of cocoa beans- - 43

Figure 4.11: surface plots showing the effect of humidity and time on the

drying of sample C of cocoa beans- - 43

Figure 4.12: Rate of moisture loss by sample-Cat different power

ratings of the sweat boxes- 44

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Figure 4.13: Surface plols showing the effect of temperature and humidity •· ¢

on the drying of sample D of cocoa beans- - 48

figure 4.14: Surface plots showing the effect of temperature and time on the

drying of sample D of cocoa beans- - 49

Figure 4.15: Surface plots showing the effect of humidity and time on the drying

of sample D of cocoa beans- - 49

Figure 4.16: Rate of moisture loss by sample -D at different

power ratings of the sweat boxes- 50