Design And Fabrication Of A Portable Mobile Dryer

ABSTRACT

In many countries of the world, the use of thermal systems in the agricultural area to conserve vegetables, fruits, coffee and other crops has shown to be practical, economical and the responsible approach environmentally.  Thermal heating systems to dry food and other crops can improve the quality of the product, while reducing wasted produce. Under the module of Advance topics in mechanical engineering projects, we were assigned to design the low cost vegetable dryer. The design of portable mobile dryer consists of several steps and sequence procedure. This report consists of back ground about project and the first chapter covers the introduction about drying and our project. Second chapter covers the literature review. The third chapter consist with design methodology The forth chapter is written on materials and methods and fifth chapter gives cost estimation for the dryer, and also covers conclusions and recommendations and final chapter consist with references.

This project report gives a great guideline about designing of low cost portable mobile dryer compare with the other competitive industrial food processing technique.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

INTRODUCTION

1.1      BACKGROUND OF THE PROJECT

• PROBLEM STATEMENT
• OBJECTIVE OF THE PROJECT
• SIGNIFICANCE OF THE PROJECT
• APPLICATION OF THE PROJECT
• SCOPE OF THE PROJECT
• LIMITATION OF THE PROJECT
• METHODOLOGY
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• OVERVIEW OF THE STUDY
• REVIEW OF SOLAR DRYING
• REVIEW OF DIFFERENT TYPES OF GRAIN DRYERS
• DESIGN CONDITION

CHAPTER THREE

3.0      SYSTEM DESIGN METHODOLOGY

• BASICS OF THE SYSTEM
• GRAIN DRYER MACHINE OPERATING PRINCIPLE
• DESIGN DIAGRAM
• INSTRUCTIONS FOR GRAIN DRYER

CHAPTER FOUR

TEST AND RESULT ANALYSIS

• CONSTRUCTION PROCEDURE AND TESTING
• CASING AND PACKAGING
• ASSEMBLING OF SECTIONS
• ECONOMIC OF THE PROJECT
• PROJECT VIABILITY
• RELIABILITY
• MAINTAINABILITY
• PROJECT EVALUATION

CHAPTER FIVE

• CONCLUSION
• RECOMMENDATION
• REFERENCES

CHAPTER ONE

1.0                                                        INTRODUCTION

1.1                                         BACKGROUND OF THE PROJECT

Drying preserves foods by removing enough moisture from food to prevent decay and spoilage. Water content of properly dried food varies from 5 to 25 percent depending on the food.

When drying foods, the key is to remove moisture as quickly as possible at a temperature that does not seriously affect the flavor, texture and color of the food.  If the temperature is too low in the beginning, microorganisms may grow before the food is adequately dried.  If the temperature is too high and the humidity too low, the food may harden on the surface. This makes it more difficult for moisture to escape and the food does not dry properly.  Although drying is a relatively simple method of food preservation, the procedure is not exact.
Food drying is a very simple, ancient skill. It requires a safe place to spread the food where dry air in large quantities can pass over and beside thin pieces. Sun is used to provide the hot dry air. Dry, clean air including dry cold air from any source will dehydrate food. Draping food over branches or spreading it on wide shallow baskets on the roof is an old widespread tradition still in use around the world.
“Drying is an excellent way to preserve food and food dryers are an appropriate food preservation technology for a sustainable world.”   Actually, solar food drying is one of the oldest agricultural techniques related to food preservation, but every year, millions of dollars worth of gross national product is lost through spoilage.  Reasons include, ignorance about preservation of produce, inadequate transportation systems during the harvest season (mostly climate related), and the low price the rural farmer receives for products during the harvest season.
Drying of crops can change this trend and is useful in most areas of the world, especially those without a high humidity during the harvesting season.  If drying of produce were widely implemented, significant savings to farmers would be achieved.  These savings could help strengthen the economic situation of numerous developing governments as well as change the nutritional condition in these same countries.

Drying generally refers to the removal of moisture by evaporation rather than by pressure or other physical means. The factures that are affecting the drying can be identified as the temperature, humidity, pressure, velocity of air and the size and the shape of the wet surface and the air moment with respect to it. There are various mechanical drying methods that are available at present. However in this work, Its operation utilizes fans for air circulation, and electric heating of drying air.

This dryer has been designed to construct from material available in the market at low cost. This especially to over come the problems encountered in the sun drying such as over drying occur, low drying rate, risk of spoilage, contaminating with impurities. Evaluation of a prototype of this dryer is important to reduce the drying losses and optimize the utilization. This dryer consists of main parts namely the body of the dryer, the drying chamber, air heater, blower or fan, fresh air inlet with filter and humid air with flow control damper.

Many other arrangements have been used to support a thin spread of food pieces Successful drying depends on:

• Enough heat to draw out moisture, without cooking the food – which is done by air heater of the dryer
• Dry air to absorb the released moisture; and Adequate air circulation to carry off the moisture – which is done by the blower or fan of the system

1.2                                                  PROBLEM STATEMENT

Grains such as Maize corns are usually stored when dried to certain percentage moisture content. In Nigeria, maize corn drying is done in dry season because of low humidity of atmospheric air and adequate sunshine. However, it is a common place to see peasant maize farmers dry their maize corn-on-cobs over fire place, but this practice contaminates the dried maize corn with smoke and usually
small quantity of maize corn-on-cob are dried. The reverse is the case during the rainy season. Unfortunately, bulk of the maize corn is harvested in the rainy season and farmers can not dry the fresh maize corn rather they sell them at very cheap prices to corn roasters and for other delicacies. To give value to farmers and also to guarantee maize corn sufficiency during scarce period, it becomes necessary that a simple but robust corn-on-cob dryer should be designed and fabricated to assist farmers have good returns on their investment especially during post-harvest handling of maize corn during rainy season.

1.3                                              OBJECTIVES OF THE STUDY

1. To obtain knowledge about industrial applications of mobile dryers.
2. To Understanding the way of selecting required components.
3. To familiarize with the workshop environment.
4. To get Familiarize with the way of project presentation.
5. To get the maximum benefit of the teamwork.
6. To obtain knowledge about report writing.

1.4                                                   SCOPE OF THE STUDY

The project is carried out in order to get outside knowledge and involve in practical applications beyond in our day-to-day academic studies under in the module of “Advanced Topics in Mechanical Engineering”. Designing of the solar dryer minimizing shortcomings associated with than low efficiency, cost not portable solar dryer

1.5                                                         APPLICATIONS

For centuries people of various nations have been preserving dates, figs, apricots, grapes, bananas, pineapples, other fruits, herbs, cassava, yams, potatoes, corn, peas, onions, garlic, carrots, peppers, milk, coffee, meat, and fish by drying. But drying is also beneficial for hay, copra (kernel of the coconut), tea and other income producing non-food crops.  This dryer is used for the above purposes.

1.6                                           LIMITATION OF THE PROJECT

1. Requires extra capital for equipment, energy and operation.
2. Lightweight and manoeuverable
3. One fan is used with plenum fitted
4. Requires some experience to operate effectively.
5. May impair quality of malting barley if not operated properly (low air temperature).

1.7                                              BENEFITS OF DRIED FOOD

“Dried foods are tasty, nutritious, lightweight, easy-to-prepare, and easy-to-store and use. The energy input is less than what is needed to freeze or can, and the storage space is minimal compared with that needed for canning jars and freezer containers.
“The nutritional value of food is only minimally affected by drying. Vitamin A is retained during drying; however, because vitamin A is light sensitive, food containing it should be stored in dark places. Yellow and dark green vegetables, such as peppers, carrots, winter squash, and sweet potatoes, have high vitamin A content. Vitamin C is destroyed by exposure to heat, although pretreating foods with lemon, orange, or pineapple juice increases vitamin C content.
“Dried foods are high in fiber and carbohydrates and low in fat, making them healthy food choices. Dried foods that are not completely dried are susceptible to mold. “Microorganisms are effectively killed when the internal temperature of food reaches 145 degrees Fahrenheit (F).”

1.8                                        PROJECT WORK ORGANISATION

The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:

Chapter one of this work is on the introduction to this study. In this chapter, the background, significance, objective limitation and problem of this study were discussed.

Chapter two is on literature review of this study. In this chapter, all the literature pertaining to this work was reviewed.

Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.

Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.

Chapter five is on conclusion, recommendation and references.