CHARACTERIZATION OF PYROLYTIC BIOFUEL PREPARED FROM BIOMASS OF Ceiba pentandra and Melicia Excelsa
ABSTRACT
Wood wastes residues collected at a sawmill along Benin Ilesha expressway in Akure Ondo State (Ceiba pentandra, Melicia excelsa and mixture of Ceiba pentandra, and Melicia excelsa) ratio 50:50 were converted to liquid bio-fuel via slow pyrolysis process at three different temperatures, 450° C, 550° C and 650° C. The physical characteristics of the liquid bio-fuel viz; oil yield, volume, density, viscosity, pH were determined. The proximate values of the feedstocks (volatile matter, ash content, and fixed carbon) were determined. The pyrolytic oil yield for Ceiba pentandra, Melicia excelsa, and a mixture of Ceiba pentandra, Melicia excelsa ranged from 17.67 % to 46.72 %, 16.33 % to 43.73 % and 16.72 % to 43.96 % respectively. Meanwhile, an increase in temperature indicates an increase in oil yield and a decrease in percentage char. The mean value for the charcoal produced ranged from 32.01 % to 47.17 % with Ceiba pentandra species having the highest charcoal produced at 450° C. The highest viscosity (87.08±2.88) was recorded for Melicia excelsa at 650° C. The heating value of the feedstocks used in this study ranged from 3305.59±67 to 33173±34.36 KJ/kg which indicates high heating value as good combustion properties that can guarantee safe handling of the Pyrolytic liquid produced from the feedstocks.
TABLE OF CONTENTS
TITTLES PAGES
ABSTRACT .................................................................................................................................... ii
DEDICATION ............................................................................................................................... iii
ACKNOWLEDGEMENT ............................................................................................................. iv
CERTIFICATION ......................................................................................................................... vi
TABLE OF CONTENTS .............................................................................................................. vii
LIST OF TABLES ........................................................................................................................ xii
LIST OF FIGURES ..................................................................................................................... xiii
LIST OF PLATES ....................................................................................................................... xiv
CHAPTER ONE
1.0 INTRODUCTION .................................................................................................................... 1
1.1 Statement of problem ................................................................................................................ 2
1.2. Objectives ................................................................................................................................ 3
1.3. Scope of the Study ................................................................................................................... 3
1.4. Justification .............................................................................................................................. 4
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CHAPTER TWO
2.0. LITERATURE REVIEW ........................................................................................................ 5
2.1 Biofuel as an alternative source of energy ..................................................................................... 5
2.1.1 Generation of Biofuel ................................................................................................... 6
2.1.1.1. First generation of biofuels ........................................................................................ 6
2.1.1.2 Second-generation biofuels ....................................................................................... 6
2.1.1.3 Third generation biofuels .......................................................................................... 7
2.1.1.4 Fourth generation biofuels ........................................................................................... 7
2.1.2 Types of biofuel ................................................................................................................. 8
2.1.2.1 Ethanol......................................................................................................................... 8
2.1.2.2 Biobutanol ................................................................................................................... 8
2.1.2.3 Biodiesel ...................................................................................................................... 9
2.2 Sustainable production of biofuel ............................................................................................. 9
2.2.1 Plants used as sustainable biofuel .................................................................................... 10
2.2.1.1 Sugarcane .................................................................................................................. 10
2.2.1.2 Jatropha ..................................................................................................................... 10
2.2.1.3 Pongamia Pinnata ...................................................................................................... 10
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2.2.2 Wood as a source of energy ............................................................................................. 11
2.3 Pyrolysis .................................................................................................................................. 11
2.3.1. Pyrolysis processes for biomass.......................................................................................... 12
2.3.2 Principles of fast pyrolysis ............................................................................................... 13
2.3.3. Feedstock preparation for pyrolysis ................................................................................ 13
2.3.4 Pyrolysis process technologies ......................................................................................... 14
2.3.4.1 Fixed Bed Reactor ..................................................................................................... 14
2.3.4.2 Ablative Processes ..................................................................................................... 14
3.3.4.3 Fluidized gas .............................................................................................................. 15
2.3.4.4 Circulating Fluidized Beds ........................................................................................ 15
2.4 Characteristic of pyrolysis liquid-bio-Oil ............................................................................... 16
2.5 Applications of bio-oil ............................................................................................................ 16
2.6 Products and their characteristics............................................................................................ 16
2.7 Biomass pyrolysis production related to biomass composition .............................................. 17
2.8 Meaning of terms .................................................................................................................... 18
2.8.1 Viscosity ........................................................................................................................... 18
2.8.2 pH value ........................................................................................................................... 18
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2.8.3 Flashpoint ........................................................................................................................ 18
2.8.4 Ash content ....................................................................................................................... 19
2.8.5 Heating value.................................................................................................................... 19
CHAPTER THREE
3.0 METHODOLOGY ................................................................................................................. 20
3.1 Sample collection .................................................................................................................... 20
3.2. Experimental set-up ............................................................................................................... 20
3.3. Sample preparation ................................................................................................................ 20
3.4 Physical properties determination ........................................................................................... 21
3.4.1 Viscosity determination.................................................................................................... 21
3.4.2 pH determination .............................................................................................................. 21
3.4.3 Density determination ...................................................................................................... 22
3.5 Proximate analysis .................................................................................................................. 22
3.5.1 Percentage volatile matter ................................................................................................ 22
3.5.2 Percentage ash content ..................................................................................................... 23
3.5.3 Percentage fixed carbon ................................................................................................... 23
3.5.4 Flashpoint test ................................................................................................................. 24
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3.6 Statistical analysis: analysis of variance for physical properties of pyrolytic oil ................... 24
CHAPTER FOUR
4.0 RESULT AND DISCUSSION ............................................................................................... 29
4.1 Physical properties of pyrolytic oil ......................................................................................... 29
4.1.1. Percentage pyrolytic oil yield (%) ................................................................................... 29
4.1.2 Charcoal produced............................................................................................................ 30
4.1.3. Volume of pyrolytic oil yield .......................................................................................... 34
4.1.5. the pH of pyrolytic oil .......................................................................................................... 37
4.1.6. Viscosity of Pyrolytic oil ................................................................................................ 39
4.2. Flashpoint of pyrolytic oil produced ................................................................................. 41
4.3. Proximate analysis and heating values of the three selected sawmill wood residues ........ 43
4.4. % oil yield, charcoal produced, and Noncombustible gas with variation in temperature. .... 48
CHAPTER FIVE .......................................................................................................................... 49
5.0 CONCLUSION ....................................................................................................................... 49
REFERENCES ............................................................................................................................. 50
CHAPTER ONE
1.0 INTRODUCTION
Energy is generated from various sources which include renewable sources that could be
replenished in a short period of time, such as solar, wind, geothermal, biomass and hydropower.
Energy could also be from nuclear source through fission and fusion of nuclear materials.
Furthermore, energy could also be produced from non renewable sources (fossil fuel) like coal,
oil and natural gas. These resources often exist in a fixed amount, or are consumed much faster
than nature can recreate them because it takes millions of years to form naturally and cannot be
replaced as fast as they are being consumed. Those sources of energy cannot be recreated in a
short period of time when used up. However, we get most of our energy from non renewable
energy sources (fossil fuel). Fossil fuel is a non renewable resource that cannot be produced, re-
grown, regenerated, or reuse on a scale which can sustain its consumption rate.
In spite of the limited supply from this source of energy, the rate at which it is being exhausted
increases on a daily basis, therefore leading to a rapid depletion of fossil fuel. A shortage of
energy is therefore envisaged which may become constrain to human development and economic
growth. This has stimulated the quest for alternative source of energy from renewable resources
to produce electricity, drive automobile and farm machines. Bio fuels have been identified as
important source of renewable energy that can complement the use of fossil fuels.
Biomass fuel is a term used for a wide variety of fuels originating from dry matter of biological
products. In the broadest sense the term is used to indicate fuels from chicken litter, bone meal,
grasses and wood. In co-firing applications the use of biomass is mostly limited to woody
biomass. The focus of this study is therefore limited to woody biomass and in the rest of this
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study the term biomass is referring only to wood. Biomass is material derived from recently
living organisms. This include plants, animals and their by products. For example, manure,
garden waste and crop residues are all sources of biomass. It is a renewable energy source based
on the carbon cycle, unlike other natural resources such as petroleum, coal and nuclear fuel.
Biofuels are produced from biological carbon source; the most common sources are
photosynthetic plants. Biofuels are renewable and environment friendly when compare with
fossil fuel that increases environmental pollution. Various plants materials are used for biofuel
manufacturing. They are also used as solid biofuel for heating and cooking. One of the
technologies used for the production of biofuel is the pyrolysis of biomass.
Pyrolysis is the thermal degradation of wood in complete absence of oxygen. Fast pyrolysis of
biomass is one of the most promising technologies in the last two decades for producing biofuel
(Manyele 2007) Fast pyrolysis is a biomass conversion system that offers high yield of liquid
product that can be used directly or upgraded. Virtually any form of biomass can be considered
for fast pyrolysis, ranging from Agricultural waste such as straw, olive pits and nutshell of
energy crops as well as forest operations residues such as bark, thinning and other solid wastes.
This research work would emphasis the pyrolysis of sawmill wood residues. The characteristics
of the liquid would therefore be carefully defined and investigated in term of chemical
characterization
1.1 Statement of problem
Fossil fuel supplies are finite and exhaustible, they are fast depleting as they are being exploited
from their sources and are going into extinction (Zerbe 1985) Fossil fuel production and
utilization threaten the environment and human health in myriad ways from the destruction of
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fishing grounds by oil spills to higher health care costs due to air pollution and the massive costs
that will be imposed on current and future generation by global warming.
There is a need to identify sustainable energy options for energy production without polluting the
environment. The renewable energy source can play a major role for sustainable development.
Among the possible renewable energy options are agricultural and forestry residues (generally
called biomass residues) which can be used as raw materials to generate energy (Encinar et al.,
1996).
1.2. Objectives
The general objective is to convert wood residues to Pyrolytic bio oil at high temperature.
The specific objectives are:
· To determine the time and quantity of pyrolytic oil produced during pyrolysis of pure
waste of Ceiba pentandra, melicia excelsa and mixture of Ceiba pentandra, and melicia
excelsa at 450° C, 550° C and 650° C respectively.
· To determine whether the yield from the mixture of the two species will be better than the
yield from the pure species without mixture
· To investigate the combustion and physical properties in the pyrolytic oil produced such
as the pH, viscosity, density, flash point and proximate analysis.
1.3. Scope of the Study
The scope of this study covers the pyrolytic conversion of sawmill wood residues of two
different species which are melicia excelsa and Ceiba pentandra at 450° C, 550° C and 650° C to
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liquid bio-oil. The characterization of the wood liquid would be investigated and evaluation
would be made for the heating value of the feedstock.
1.4. Justification
There have been studies that prove the many benefits of substituting fossil/traditional fuels
(petroleum, etc) with biofuels such as biodiesel and ethanol. In its simplest sense, such biofuels
are biodegradable which means they are derived from organic materials. They are naturally
renewable. It can create numerous jobs since our own farmers can practically make them
domestically.
Consequently, our reliance on fossil fuels will be significantly reduced. Moreover, these biofuels
emit non-toxic and cleaner emissions in comparison to traditional fuels. These alternative fuels
also do not promote global warming, since the carbon they emit is taken back to the
environment. Besides global production of biofuels is booming, as higher oil prices and
technological breakthroughs have made it a more profitable business. The first generation biofuel
uses wheat, starch, sugarcane, rapeseed, cassava, among other as feedstocks in production of
biofuel and this had caused and reduced food shortage globally. In light of this, saw dusts that
are to be regarded as waste in many sawmill wood industries can be use as alternative to
agricultural products for producing biofeul to prevent food insecurity resulting from the use of
agricultural products as biofeul.
.