Determination Of Wood Species Utilized In Selected Sawmills, Waste Volumes And Preference For Domestic Energy In Abia State, Nigeria
ABSTRACT
Waste generation is a
concomitant aspect of living; it cannot be banished but can only be managed. Wood
Species utilized in selected sawmills, volume of wood wastes and its preference
for domestic energy in Abia State was carried in Timber markets of
Aba North, Umuahia North and Bende Local Government areas of Abia State.
The processed wood species were identified and their abundance determined; the
number and volume of logs and also that of the converted lumber were determined
and then the volume of wood wastes generated in the timber sawmills were
evaluated. Menhinick’s Index (D) was used to calculate the proportional
abundance of the processed wood species. The findings show that across the
three local government areas, wood
species encountered were not abundantly diversed in their sources of origin
which is the forest. The sawmills had their indices values less than 1.
Measurements of diameter at large end of log, diameter at mid-point of log,
diameter at small end of log, length of sawn lumber, breadth and thickness of
sawn lumber were taken for a period of six (6) days per week for twenty four
(24) weeks. The overall mean values of number of logs converted per week in the
three selected LGAs are Aba North (177.07), Umuahia North (183.90), Bende
(150.43) while the overall mean volume of logs converted per week in the
selected LGAs were Aba North (34.11m3), Umuahia North (33.32 m3),
Bende (21.57 m3); the overall mean number of converted lumber per
week in the three selected LGAs were Aba North (1124.72), Umuahia North
(1045.68), Bende (705.23);the overall mean values of the volume of converted
lumber per week were Aba North (26.36), Umuahia North (21.90), Bende (16.65).
Correlation analysis revealed a significant negative correlation between volume
of wood waste generated per week and volume of sawn timber processed among the
surveyed sawmills (F17, 67 = 2.564, P = 0.003) and the locations (F2,97 =
5.557, P = 0.005). Also, there was a positive correlation between volume of
wood wastes and volume of logs. The results showed that wood wastes species
commonly used in the study areas are Gmelina (Gmelina arborea) with the
highest percentage of preference of 17.36%. This was followed by Teak (Tectonia grandis) with a preference
value of 13.22%. The people also preferred Ceiba (Ceiba pentandra) wood wastes, with a value of 9.92%, and Obeche (Triplochiton scleroxylon), having a percentage value of 6.17% followed by Ekki (Lophira alata) and Iroko (Milicia excelsa) with a value of 4.10%.
Other wood waste species are also preferred in various insignificant
percentages. The Chi-square (x2) statistical analysis shows that at
5% level of probability (p<0.05), the wood wastes species used in the study
locations were not significantly different. Furthermore, alternative sources of
energy should be encouraged and also the public should be advised on the need
to participate in afforestation programmes because of the indiscriminate
exploitation of the forest.
TABLE OF
CONTENTS
Title
page i
Declaration ii
Certification iii
Dedication iv
Acknowledgements v
Table
of Contents vi
List
of Tables ix
List
of Figures x
List
of Plates xi
Abstract xii
CHAPTER 1:
INTRODUCTION
1.1 Background
of the Study 1
1.2 Statement of Problem 13
1.3 Objectives of Study 13
1.4 Significance
of the study 14
1.5 Scope of the Study 16
CHAPTER
2: LITERATURE REVIEW
2.1 The
Potential Use of Wood Residue for Energy Generation 23
2.2 Utilization
of Wood Waste for Energy Generation 25
2.3 Sources
of Wood Wastes 27
2.5 Mill-Site Generated Wood Waste 36
2.7 Alternative Uses of Residues 40
2.8 Uses of Wood Waste 41
2.8.1 Fuel production 41
2.8.2 Briquettes 41
2.8.3 Pellets 42
2.8.4 Wood
chips 42
2.8.5 Charcoal 42
2.8.6 Bark utilization 42
2.8.7 On-site energy generation 43
2.9 Heat
Generation and Incineration 43
2.10 Strict
Heat Generation 43
2.11 Heat
and Power Generation 44
2.12 Problems
of Wood Waste to the Environment 44
2.13 Management
of Sawmill Wastes in Nigeria 47
2.14 Wood
Wastes Management Strategies 53
2.15 Management
Options for Wood Wastes 55
2.15.1
Briquette production 55
2.15.2 Hard board 56
2.15.3 Particle board 56
2.15.4 Fibre board 57
2.15.5 Absorbents and landscape uses 57
2.16 Prospects
for Optimizing Wood Waste Utilization in Nigeria 58
2.17 Classification of Wood Waste 59
2.18 Characterization of Wood Waste 60
2.19 Environmental Challenges of Wood Disposal 61
2.20 Prospects of Wood Waste Gasification for
Power Production 64
2.21 Wood Waste Energy in
Foreign Countries 64
CHAPTER 3:
MATERIALS AND METHODS
3.1 Study Area 69
3.2 Sources of
Data 73
3.3 Sampling
Technique/Research Design 73
3.4 Data
Collection 74
3.5 Experimental
Procedure 75
3.5.1 Identification
and estimation of the processed wood species abundance 75
3.5.2
Determination of log volume 76
3.5.3
Determination of lumber volume 76
3.5.4
Wood waste volume computation 77
3.5.5
Sawmill conversion efficiency 77
3.5.6
To compare the use of wood wastes of different tree
species for energy 77
3.6 Data Analysis and Experimental Design 78
CHAPTER 4: RESULTS AND DISCUSSION
4.1 Identification of the Processed Wood
Species in the Mills 79
4.2 Determination of the Identified Wood
Species Abundance in the Mills 82
4.2.1 Estimation of
the wood species abundance using Menhinick’s index 91
4.3 Determination of the Number and Volume of
Logs in the Study Areas 94
4.3.1 Determination of the number of the logs in
the study areas 94
4.3.2 Determination of the volume of logs in the
study area 100
4.3.2.1 Determination of log volume converted in the
sawmills 105
4.4 Determination of the Number and Volume of
Converted Lumber in the
Study Areas 106
4.4.1 Determination of the number of sawn lumber
converted in the study areas 106
4.4.1.1 Determination of number of lumber converted in
the sawmills 111
4.4.2 Determination of the volume of sawn lumber
converted in the study areas 112
4.4.2.1 Determination of lumber volume 117
4.5 Determination of the Volume Wood Wastes 118
4.5.1 Determination of the volume of wood wastes
in the study area 118
4.5.2 Wood waste volume computation 123
4.5.3 Determination of the percentage volume of
wood wastes in the study area 125
4.6 Conversion Efficiency of the Sawmill 131
4.6.1 Determination of conversion efficiency of
the sawmill 131
4.6.2 Sawmill efficiency 136
4.7 Comparison
of the Use of Wood Waste for Energy 145
4.7.1 Demographic
data of respondents 145
4.7.2 Comparison
of wood species wastes preference and reasons for
preference
147
CHAPTER
5: CONCLUSION AND RECOMMENDATIONS
5.1 Conclusion 150
5.2 Recommendations 151
5.3 Contribution to Knowledge 152
5.4 Suggestion
for Further Research 152
REFERENCES 153
APPENDIX 166
QUESTIONNAIRE 167
LIST OF TABLES
2.1: Sources of wood residue 28
2.2: Several outlet areas 40
4.1.1: Wood species identified in all
the selected sawmills across the
three local government
areas 80
4.2.1: Number of wood frequencies
encountered in the sawmills of Aba
North Local Government
Area 85
4.2.2: Number
of wood frequencies encountered in the sawmills of
Umuahia
North Local Government Area 88
4.2.3: Number of wood frequencies
encountered in the sawmills of
Bende Local Government
Area 90
4.2.4: Menhinick’s Index values across
the various sawmills in the three
local government areas 93
4.3.1: Number
of logs converted per week in the three selected LGAs of
Abia
State 96
4.3.2: Volume
of logs converted per week in the three selected LGAs
of
Abia State 102
4.4.1: Number
of converted lumber per week in the three (3) selected
LGAs
of Abia State 108
4.4.2: Volume
of converted lumber per week in the three selected
LGAs
of Abia State 114
4.5.1: Volume
of wood waste generated per week in the three (3)
selected
LGAs of Abia State 120
4.5.2: Percentage
volume of wood waste generated per week in the
three
selected LGAs of Abia State 127
4.6.1: Conversion
efficiency of the sawmills in the three selected
LGAs
of Abia State 133
4.7: Categorical description of
sawmill operations across three Local Government Areas in Abia State 142
4.8 The relationship between
volumes of logs and volumes of sawn
timber for the purpose
of predicting the wood wastes 144
4.9.1: Demographic
data of the respondents 146
4.9.2: Comparison
of wood species wastes preference and reasons for preference 149
LIST OF FIGURES
3.1: Map of
Abia State indicating the study locations 72
4.1: Mean value of the number of logs converted
in the three study areas 98
4.2: Differences in the number of logs converted
per week in sawmills located
in Abia State 99
4.3: Mean values of the volume of logs
converted in the three study areas 104
4.4: Volumes of logs
converted per week in sawmills located in Abia State 105
4.5: Mean values of the number of sawn lumber in
the three study areas 110
4.6: Variation in the number of sawn timber per
week in sawmills located in
Abia State 111
4.7: Mean values of the volume of sawn lumber in
the three study areas 116
4.8: Distribution of volumes of sawn timber per
week in sawmills located in
Abia State 117
4.9: Mean values of the volume of wood wastes in
the three study areas 122
4.10: Differences in the volumes of wood waste
generated per week in sawmills
located in Abia State 123
4.11: Relationship between the volume of wood
waste and volumes of sawn
timber in sawmills located in Abia
State 124
4.12: Mean values of the percentage volume of wood
wastes in the three study
areas 129
4.13: Differences in the percentage volume of wood
waste generated per week
in sawmills located
in Abia State 130
4.14: Variation in sawmill efficiency in sawmills
located in Abia State 137
4.15: Mean values of the sawmill efficiency in the three study areas 138
4.16: Variations in the impact of sawmill
efficiency on percentage wood waste
generated per week
across sawmills in the surveyed locations 139
4.17: Differences in conversion ratio in sawmills
located in Abia State 140
4.18: The impacts of volume of log converted and
volume of sawn timber on
volume of wood waste generated
across locations and sawmills in Abia
State 144
LIST OF PLATES
2.1: Saw
dust waste produced by vertical band saw 27
2.2: Pictorial
diagram of a heap of Sawmill 33
2.3: Pictorial
diagram of a heap of Offcuts 35
2.4: Wood
Shavings gotten from wood conversion 53
2.5: Harvesting
of some of the tree species used 63
2.6: Logs
ready to be measured before conversion 65
2.7: Wood chips 66
2.8: Wood shavings 66
2.9: Wood bark 67
2.10: Sawdust 67
2.11: Wood
offcuts 68
0.0
CHUKWUEMEKA, C (2023). Determination Of Wood Species Utilized In Selected Sawmills, Waste Volumes And Preference For Domestic Energy In Abia State, Nigeria. Repository.mouau.edu.ng: Retrieved Nov 23, 2024, from https://repository.mouau.edu.ng/work/view/determination-of-wood-species-utilized-in-selected-sawmills-waste-volumes-and-preference-for-domestic-energy-in-abia-state-nigeria-7-2
CHUKWUEMEKA, CHUKWUEMEKA. "Determination Of Wood Species Utilized In Selected Sawmills, Waste Volumes And Preference For Domestic Energy In Abia State, Nigeria" Repository.mouau.edu.ng. Repository.mouau.edu.ng, 20 Jul. 2023, https://repository.mouau.edu.ng/work/view/determination-of-wood-species-utilized-in-selected-sawmills-waste-volumes-and-preference-for-domestic-energy-in-abia-state-nigeria-7-2. Accessed 23 Nov. 2024.
CHUKWUEMEKA, CHUKWUEMEKA. "Determination Of Wood Species Utilized In Selected Sawmills, Waste Volumes And Preference For Domestic Energy In Abia State, Nigeria". Repository.mouau.edu.ng, Repository.mouau.edu.ng, 20 Jul. 2023. Web. 23 Nov. 2024. < https://repository.mouau.edu.ng/work/view/determination-of-wood-species-utilized-in-selected-sawmills-waste-volumes-and-preference-for-domestic-energy-in-abia-state-nigeria-7-2 >.
CHUKWUEMEKA, CHUKWUEMEKA. "Determination Of Wood Species Utilized In Selected Sawmills, Waste Volumes And Preference For Domestic Energy In Abia State, Nigeria" Repository.mouau.edu.ng (2023). Accessed 23 Nov. 2024. https://repository.mouau.edu.ng/work/view/determination-of-wood-species-utilized-in-selected-sawmills-waste-volumes-and-preference-for-domestic-energy-in-abia-state-nigeria-7-2