Assessing Factors Affecting Transitional Development of Small Scale to Medium Scale Enterprise ...

115 Pages·2006·1.21 MB·English

ADDIS ABABA UNIVERSITY
SCHOOL OF GRADUATE STUDIES

EVALUATION OF ECONOMIC AND TECHNICAL
FEASIBILITY OF
BIOGAS PRODUCTION FROM POULTRY MANURE IN
ELFORA
AGRO INDUSTRY DEBRE ZEIT

BY

EBRAHIM ALI

JULY, 2006
ADDIS ABABA
EVALUATION OF ECONOMIC AND TECHNICAL FEASIBILITY OF
BIOGAS PRODUCTION FROM POULTRY MANURE IN ELFORA
AGRO INDUSTRY DEBRE ZEIT

A Thesis Submitted to the School of Graduate Studies of Addis
Ababa University in Partial Fulfillment of the Requirements for the Degree
of Master of Science in Environmental Science

BY

EBRAHIM ALI

ii
Acknowledgment
I am very grateful to all whose contribution has enabled me to make this
thesis a reality. To list all the names is difficult. I acknowledge Defense
University College for sponsoring me on this course.
My special thanks are to Araya Asfaw (PhD) ,dean, faculty of science, Addis
Ababa University for his helpful guidance, academic instruction, invaluable
critical comments and all assistance rendered to me during my work.
I am indebted to my family who strongly encouraged me to pursue my
education and to complete my study successfully.
I thank to all my friends for inspiring me in the world of academics and
encouragement.
I am indebted to all the staff members of the Debre Zeit ELFORA poultry
farm for their sympathy and help during my fieldwork; special thanks are to
Ato Birihanu Damite for his encouragement and supplying me with the
pertinent documents. Finally yet importantly, I thank to Ato Ayalew Tesma for
helping me during my sample collection.

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Abstract
The economic and technical feasibility of poultry manure to methane conversion
using anaerobic digestion and electricity generation was studied in ELFORA poultry
farm in Debre Zeit, Ethiopia using three sets of data; chemical analysis of wet
manure, annual on farm wet poultry manure production and annual electric
consumption of the poultry farm.

Total solids (% wet), volatile solids (% TS) and PH were analyzed as reported in
Standard Methods ASTM and AOAC publications. Phosphorus was analyzed using
Hatch Analysis system. Ultimate analysis of carbon, nitrogen, hydrogen, oxygen and
sulfur were done using elemental analysis method. The result shows low carbon
nitrogen ratio of the manure indicating that wet poultry manure easily ferments in
anaerobic digestion. The estimated daily volume of wet manure generated on farm is
27,397kg on average. The amount of nitrogen and phosphorous in the slurry was
estimated to be 97.8 kg and 96.94 kg respectively from 4328 kg of dry matter which
constitutes a good fertilizer potential .

The estimated methane production with loading rate of 3.03 kg VS per meter cube is
655meter cube per day for complete mix digester, 807meter cube with loading rate of
4.8kg VS per meter cube for plug flow digester and 605 meter cube with loading rate
of 0.39kgVS/m3 for covered lagoon digester was estimated. Poultry manure with high
content of VS and nitrogen can have high methane yield on site, which could be used
to fuel an engine/ generator of 86kw, 94kw and 115kw for complete mix, plug flow
and covered lagoon digesters respectively.

The carbon dioxide equivalents of the maximum methane generated on-farm were
calculated to be 3.739kt per year. This yield was found to be equal to the carbon
dioxide emitted from the distraction of 1,402 acres forestland. The calculated annual
energy equivalent of the yield is 12.37-tera joule with a calorific value of 2.95 tera
calorie and 295 Toe. Economics of anaerobic digestion for all three types of digesters
show positive NPV indicating that on farm anaerobic digestion is feasible.

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Table of Contents
Acknowledgment..........................................................................................iii
Abstract.......................................................................................................iv
Table of Contents ..........................................................................................v
List of Tables................................................................................................ix
List of Figures ...............................................................................................x
Acronyms.....................................................................................................xi
Chapter One..................................................................................................1
Introduction..................................................................................................1
1.1 Background and justification............................................................1
1.2 Objectives of the Research....................................................................2
1.2.1 General objective............................................................................2
1.2.2 Specific Objectives..........................................................................2
1.3 Nomenclature.......................................................................................3
1.4 Outline of the thesis.............................................................................3
Chapter Two..................................................................................................4
Literature Review...........................................................................................4
2.1 Description of the study area................................................................4
2.2 General Description of Poultry Manure.................................................5
2.3 Poultry Manure Composition................................................................5
2.3.1 Basic Physical Characteristics of Poultry Manure ...........................6
2.3.1.1 Moisture content......................................................................6
2.3.1.2 Density ....................................................................................6
2.3.1.3 Odor ........................................................................................6
2.4 Chemical Composition of Poultry Manure.............................................7
2.5 Poultry Manure Transformation............................................................8
2.6 Poultry Manure Management................................................................8
2.7.1 Anaerobic Digestion........................................................................9
2.7.2 Temperature.................................................................................10
2.7.3 Concentration of Solids ................................................................11
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2.7.4 Retention Time.................................Error! Bookmark not defined.
2.7.5 Volatile Solids and Loading Rate...................................................12
2.7.6 PH values.....................................................................................12
2.7.7 Feed Materials and Nutrients .......................................................12
2.8 Poultry Manure Handling ...................................................................13
2.8.1 Collection.....................................................................................13
2.8.2 Transfer and Storage....................................................................13
2.8.3 Removal and Transport................................................................14
2.9 Composition of Biogas........................................................................14
2.9.1 Ultimate Methane Yield ................................................................14
2.9.2 Actual Methane Yield....................................................................15
2.10 Emission Reduction..........................................................................15
2.11 Reactor Design.................................................................................16
2.11.1 Covered Anaerobic Digester........................................................17
2.11.2 Complete-Mix Digesters..............................................................17
2.11.3 Plug Flow Digester......................................................................18
2.12 Economics of Biogas production.......................................................19
Chapter Three.............................................................................................22
Methodology................................................................................................22
3.1 Chemical Analysis of Manure .............................................................22
3.1.1 Sampling......................................................................................22
3.1.2 Proximate Analysis.......................................................................23
3.1.3 Ultimate Analysis.........................................................................23
3.2 The Evaluation Approach for Manure Digestion (Reactor ..........Analysis)
24
3.3 The Economic Approach for Methane and Electricity ............Production
24
3.4 Materials and Instruments.................................................................25
3.5 Limitation of the Study.......................................................................25
Chapter 4....................................................................................................26
Results and Discussion...............................................................................26
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4.1 Characteristics of Poultry Manure ......................................................26
4.2 Manure Generation ............................................................................27
4.3 Methane Production...........................................................................29
4.4 Carbon- Nitrogen Ratio.......................................................................30
4.5 Slurry.................................................................................................31
4.6 Manure Management..........................................................................32
4.7 Electricity Generation.........................................................................32
4.7.1 On Farm Electric Consumption....................................................32
4.7.2. Complete Mix Digester.................................................................33
4.7.2.1 Biogas Performance...................................................................34
4.7.2.2 Annual Farm Energy Usage....................................................34
4.7.2.3 Farm Energy Capacity............................................................35
4.7.2.4 Costs......................................................................................36
4.7.3 Plug Flow Digester........................................................................38
4.7.3.1 Biogas Performance................................................................39
4.7.3.2 On Farm Energy Usage ..........................................................40
4.7.3.3 Farm Saving...........................................................................41
4.7.3.4 On Farm Energy Capacity ......................................................41
4.7.4 Covered Lagoon............................................................................44
4.7.4.1 Biogas Performance................................................................44
4.7.4.2 Farm Energy Capacity............................................................45
4.7.4.4 On Farm Energy Usage ..........................................................46
4.7.4.4 On Farm Saving.....................................................................46
4.8 Emission Reduction............................................................................47
4.9 Environmental Benefits......................................................................48
4.10 Energy Equivalent............................................................................49
4.11 Oil Equivalent ..................................................................................49
Chapter Five................................................................................................50
Conclusion and Recommendations..............................................................50
5.1 Conclusions .......................................................................................50
5.2 Recommendations..............................................................................52
vii
Reference ....................................................................................................53
Appendix.....................................................................................................58
Plates..........................................................................................................68
Declaration..................................................................................................69

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List of Tables
Table 1- Approximate percentage of intake nutrient excreted in the
Poultry manure…………………………………………………………….7
Table 2- Manure production and fertilizer elements in kg/hen/year…..…7
Table 3- Transformation process in poultry manure………………………....8
Table 4- Summery of poultry manure management system………………..9
Table 5- Characteristics of poultry litter……………………….………………10
Table 6-Composition of biogas……………………………………………………14
Table 7-Proximate analysis of poultry manure………………………….……25
Table 8- Ultimate analysis of poultry manure………………………………..25
Table 9- On-farm manure production………………….………………………26
Table 10- On-farm electric consumption and cost…………………….…….29
Table 11- Annual average Electricity consumption and cost
in ELFORA poultry farm in 2005-2006 ……………….………..31
Table 12- Biogas performance complete mix digester ………………………32
Table 13- Annual farm energy usage…………………………………….…….33
Table 14- Farm Energy Capacity, Complete mix digester………….….…..34
Table 15- Capital cost complete mix digester. ……………………….….…35
Table 16- Financial result complete mix digester…………………….……..36
Table 17- Characteristics of feedstock ………………………………….……..37
Table 18- Biogas performance plug flow digester…………………………….38
Table 19- Annual Farm Energy Usage plug flow digester…………………..38
Table 20- Farm Energy Capacity Plug flow digester……………………….…39
Table 21- Cost estimation plug flow digester……………..…………………...40
Table 22- Financial result Plug flow digester…………………………………..41
Table 23- Biogas performance covered lagoon…………………………………42
Table 24- Farm Energy Capacity, covered lagoon………………………….....42
Table 25- Farm Energy Usage Covered Lagoon………………………………..43
Table 26- Capital costs covered lagoon………………………………………….44
Table 27- Financial result covered lagoon………………………………………44
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List of Figures
Fig. 1 – Map of Debre Zeit……………………………………………………4
Fig. 2- Manure sample site………………………………………………….22
Fig. 3- farm energy usage complete mix digester………………………34
Fig. 4 -farm energy capacity complete mix digester…………………..35
Fig. 5- farm energy plug flow……………………………………………….39
Fig. 6-farm energy capacity plug flow…………………………………….40
Fig. 7- farm energy capacity covered lagoon…………………………….43

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