Construction Performance And Evaluation Of A Charcoal Baking Oven

This research, concerns the design and construction of a charcoal baking oven using locally available materials. The baking oven in this work has a rectangular box like shape with a total baking area of 315000mm². The oven is used for baking, drying and warming of food e.g cakes, bread, fish, meat etc. It is constructed with mild steel and angle bars. It comprises baking tray, housing frame, charcoal heating tray and baking chamber door. The oven is capable of generating 1488KJ of heat energy. The maximum temperature attainable with the oven is about 500 degree Celsius. The cost of producing one unit of this charcoal baking oven is about fifty five thousand naira only.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

INTRODUCTION

1.1      BACKGROUND OF THE PROJECT

• OBJECTIVE OF THE PROJECT
• IMPORTANCE OF OVEN
• LIMITATION OF THE PROJECT
• PURPOSE OF THE PROJECT
• SIGNIFICANCE OF THE PROJECT
• DELIMITATION OF THE PROJECT
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• HISTORICAL BACKGROUND OF OVENS
• REVIEW OF DIFFERENT TYPES OF OVENS
• REVIEW OF CHARCOAL OVEN
• TYPES OF CHARCOAL OVENS
• TECHNICAL DETAILS OF CHARCOAL OVEN

CHAPTER THREE

• METHODOLOGY
• INTRODUCTION
• METHOD OF CONSTRUCTION

3.3      TEORETICAL DESIGN CALCULATIONS OF THE MAXIMUM HEAT GENERATED IN OVEN(Q)

CHAPTER FOUR

4.0        TESTING, RESULTS AND DISCUSSION OF RESULTS

4.1           RESULTS

4.2           ASSEMBLING OF SECTIONS

• DISCUSSION OF RESULTS
• BILL OF ENGINEERING MEASUREMENT AND EVALUATION

CHAPTER FIVE

• CONCLUSION
• RECOMMENDATION
• REFERENCES

CHAPTER ONE

1.0                                                        INTRODUCTION

Baking is the process that uses an oven or hotplate to cook a wide range of flour-based foods [5]. According to [13], in free air solid fuels burn at a temperature of only 240⁰C, which is too low a temperature for perfect reactions to occur, with heat produced through convection being largely lost, smoke particles are evolved without being fully burnt and the supply of air difficult to controlled but by enclosing the fire in a chamber and connecting it to a chimney, draft(draught) is generated by way of pulling fresh air through the burning fuel thereby causing the temperature of combustion to rise to a point of 600⁰C where efficient combustion is achieved also the enclosure allows the ingress of air to be regulated and losses by convection are almost eliminated. [7] posits that baking requires very high temperature around 250⁰C which therefore needs a larger amount of thermal energy input and that due to lack of electricity, biomass energy is mostly used for baking in developing countries. There are two categories of ovens: those that are heated internally and those that have a separate heat source [14]. The baking oven in this article is a rectangular box-like structure within which heat is generated and maintained. The oven is usually provided with insulation or lagged to prevent heat loss through the boundary and mostly used for baking, drying and warming needs, making it imperative therefore to design an oven that can be ignited to attain various temperature levels. The thermal energy is generated through conversion of chemical energy and can be utilized for both domestic and industrial purposes. This research paper therefore, takes a look at the design and construction of a charcoal baking oven using locally available

materials. According to [9], Charcoal is a black substance that resembles coal that is used as a source of fuel made from wood that has been burnt or charred, while being deprived of oxygen so that what is left is an impure carbon residue. This design has a little modification when compared to the conventional charcoal baking oven as a case study for entrepreneurial development, particularly adapted for rural areas where there is no electricity as well as natural cooking gas or where both are exceptionally expensive and therefore unaffordable by the populace. This design is meant for domestic use in terms of baking, roasting and drying of food like bread, cake, fish, meat e.t.c. This design could also serve some engineering purpose which include the area of heat treatment of metals. Heat treatment is used to alter mechanical properties of a metal by effecting changes in its microstructure [3].

The main components of the improved design are as follows; the charcoal heating tray, baking chamber door, baking tray, housing frame and a manually operated blower. The operating temperature of the charcoal baking oven ranges from 250^oC to 300^oC. Thermal heat losses resulting from flow through the wall of the oven to the surrounding are highly reduced by means of lagging. The insulating material precisely, reinforced fibre was used to reduce the amount of heat loss and maintain the temperature within the required range of 250^oC to 300^oC. The use of the charcoal baking oven is limited to domestic farmers and industries in rural areas and is capable of drying and baking 20kg of bread and farm produce. The charcoal baking oven should be kept in dry environment and away from the rain to avoid corrosion.

According to [8] the most important thing in a bakery is the oven and before obtaining an oven a baker should consider oven prices, fuel availability, and affordability, possible assistance, supply and quality of materials, maintenance requirements etc. The charcoal baking oven was designed to ease and eliminate the stress and drudgery the rural dwellers and industries in rural areas that have no easy access to natural cooking gas and electricity go through during baking and drying food items such as bread & snacks. This design and construction of this oven, therefore becomes significantly imperative for the rural dwellers so as to emancipate them from the crude way of drying & baking with firewood. This will also go a long way to minimize the level of environmental pollution caused by the incomplete combustion characterized with cooking with firewood. This research design in summary therefore seeks to proffer assistance to the local and medium scale industries involved in baking and drying business in their quest for a convenient and cheap method of baking. The oven will be useful to the low income earners and medium scale industries in the rural areas due to either the high cost or total unavailability of natural cooking gas in the rural areas. This is in line with [4] position that Entrepreneurship has the ability to raise productivity through various forms of innovations and to create jobs through the formation of new enterprises especially small and medium scale enterprises.

An oven is a thermally insulated chamber used for the heating, baking or drying of a substance and most commonly used for cooking.

This project is as a result of increasing interest. Essentially, the idea, as demonstrated in an existing design, arises in the project students a feeling of motivation, and hence the search for a way to bring it to reality in a simple, yet intelligent design, like this. This project is designed to make the students utilize as many theoretical and practical concept as have been instructed in Alston to mechanical engineering workshop technology. Students are expected to learn and apply concepts, principles about energy specially the conversions of  electrical energy to thermal energy, conduction and conventional heat transfer etc.

Charcoal ovens are indirectly fired ovens that use wood fuel for cooking. While the traditional wood-fired oven is like a masonry oven (mud oven), such ovens can also be built out of cobor iron. Wood-fired ovens are distinct from wood-fired stoves that have a hot cooking surface for pots and pans like electric stove. A wood stove may also have an oven separate from the fire chamber. Regardless of material they all have an oven chamber consisting of a floor (or hearth), a dome and an entry (oven opening). The wood fired oven has an advantage of the less capital requirement, ease of construction and similarly the wood fired has the disadvantage of longer baking time, the product has not baked uniformly and has the problem of the changing the original flavor of the product.

1.2                                            OBJECTIVES OF THE PROJECT

This project is undertaken to:

(2)    Disclose the different types of process in the manufacturing of a charcoal

(3)    Exploit the local facilities available in the construction of the oven as against imported ovens.

(4)    To exhibit the usefulness of a charcoal oven in the economy and technology growth of the nation.

(5)    To know the convenience in the use of charcoal for operation of ovens.

(6)    Discover the basic principle involved in the design and maintenance of a charcoal oven.

1.3                                                IMPORTANCE OF OVENS

In actual analytical enunciation an oven is an enclosed chamber in which things are heated or cooked with charcoal. Its importance borders around its function, which are as follows;

(i)    It is used to meet the everyday basic need of cooking, (baking, toasting, gritting, toasting) of food materials for human consumption.

(ii)    Ovens are used for heat treatment of substance in laboratories and industries.

(iii)    Also as a means of preservation by heat application to perishable materials (organic and inorganic) in general.

(iv)    Sterilization of instruments and equipment for industrial use is done by heat application using oven.

(v)    Expelling of moisture content to a required measure in some substance is also done using oven.

(vi)    Early manufactured ovens where used as a source of room heaters during cold weathers in cold climates.

Other importance boarding around its energy source is that the use an alternative source of energy when either fossil fuel or electricity is not available.  This can be relatively save cost when necessitated.

1.4                                                 LIMITATIONS OF OVEN

Disadvantages in the use of ovens:

(i)    Cleaning and repair is a time- consuming endeavor.

(ii)    Expect for mass production singular construction is relatively expensive to produce.

(iii)    If precautions are not well carried out, it can result in fire hazard, which is dangerous to life and properties.

(iv)   Because ovens provide heat for one or more areas, the temperature may vary in different areas of the oven.

(v)    Oils and moisture collected on metal surface can end up trying to rust the metal coating if not clean regularly.

(vi)   It is expensive to operate in high volume operations.

(vii)    Speed seems to be the key factor and time taken to get to required constant temperature can be wastage of time.

(viii)    Access to internal component n case of adjustment and maintenance is tasking as it requires an entire disassembling.

(ix)    In case of mechanical faults resulting from shut down, an entire disassembling and requires is required.

(x)    Due to its function by heating, there is always a premature wear or mechanical failure of some of the internal component.

1.5                                              PURPOSE OF THIS PROJECT

This study is to devise a means of producing an oven with charcoal to address the following:

(1)            The problem of sooty pare-heating as observed in vaporizing cookers.

(2)             Economically, this equipment is designed for cost reduction and easy to maintain.

(2)        To meet up with inadequate availability of fire wood through deforestation.

1.6                                       SIGNIFICANCE OF PROJECT

This project work is intended to serve as a catalogue and manual for the construction, installation, maintenance and repair of different possible faults in charcoal oven, it is also of a great benefit to the department and society as it will serve as medium of knowing the principle of operating the model work. It serve as a standard means for cooking.

1.7                                         DELIMITATION OF THE PROJECT

1. There is freedom of location and general adaptability.
2. It entails good cooking condition, cleanliness, quietness and ambient temperature.
3. Uniform of temperature within narrow limit with the electrical chamber.
4. Capital cost, running and maintenance cost of oven are low.

1.8                                                         PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.