Energy Production from Biomass with the E-M-F-System

Band 32, Schriftenreihe des Bauhaus-Instituts für zukunftsweisende Infrastruktursysteme (b.is)
ISBN: 978-3-944101-57-6
Verlag: Rhombos-Verlag

Buch, Englisch, 270 Seiten, GB, Format (B × H): 1700 mm x 2400 mm, Gewicht: 600 g

In a general sense, the main concern of this thesis is large-scale bio-ethanol production, particularly the attempt to find a convenient and suitable way to use its by-product known as stillage. Using stillage to produce energy is the main focus subject of this thesis. Large amounts of available by-product stillage with high organic content have been of great interest for many researchers in the search for a better way to utilize it. It is supposed that stillage used as pro- posed in this study would create more energy efficiency and more positive environmental effects compared with the traditional and popular utilization of stillage as animal feed.
A system was developed during this study for the production of biogas and bio-fertilizer from biomass left after the production of bio-ethanol via the processes of digestion and composting. This system has been named as the E-M-F- System. Stillage and stillage digestate are the main points of connection in these three biological processes. Currently, some related research is being con- ducted in the combination of bio-ethanol production with biogas production, and biogas production with fertilizer production. In Prasad Kaparaju’s study, the thermophilic anaerobic digestion of wheat straw stillage was investigated. Results showed that higher methane yields of 324 ml/g VS added were obtained at stillage concentrations of 12.8 g VS/l [95]. Wilkie, A.C. has done the most research on sugar, starch and cellulosic-based stillages under thermophilic and mesophilic digestion conditions. He has summarized the whole production chain from biomass planting and harvesting to stillage’s further utilization to find sustainable and economically viable solutions [4]. The concept of combin- ing all these three processes was proposed in some previous studies; however they did not go as far as detailing the methods or testing the concept [99]. This study aims to address that gap and carry out a basic analysis of feasibility and evaluation of a combined system, the proposed E-M-F-System.
In this study, two ways were utilized in parallel to analyze the feasibility of the E-M-F-System, firstly through theoretical analysis and secondly through labora- tory research. Subsequently, a rigorous and thorough balance analysis assessment including mass, energy and CO2-eq. perspectives was carried out for this system. In order to make further utilization of this system to produce bio-energy easier and more accessible, a case study using sweet potato in China was undertaken as an example. Furthermore, a tool box was compiled in the hopes of creating an innovative platform for the convenient utilization of this system for other projects and the results of assessment and analysis was compiled into an excel spreadsheet.


Overall, through the study of this E-M-F-System, the results reveal that, this system could be of great importance to the current global energy situation. This system has its own particular advantages and strengths. Similar assessment or analysis of it could be easily adopted in other projects due to its broad utilization feasibility and possibility. Moreover, further attempts or important modifications related to the E-M-F-System can be carried out according to the needs of specified projects. This biomass-energy-environment system could be the basis of future studies on the combination of biological processes.

Autoren/Hrsg.

Liu, Yang

Inhaltsverzeichnis

Content
Acknowledgements I
Content III
Table list VII
Figure list X
Abbreviation and definition .. XII
Abstract XV

1 Introduction 1
1.1 Background of the study - energy and environmental problems . 1
1.2 Purpose and significance of the study 2
1.3 Research methods of the study – E-M-F-System 4
1.4 Anticipative study results . 5
1.5 Prospects of the study 5

2 Biomass 7
2.1 Biomass definition and characteristics 7
2.2 General biomass utilization: biomass for energy 8
2.3 Biomass species and quantity potential 10
2.4 Biomass utilization for the E-M-F-System 14
2.4.1 Characteristics and utilization of biomass in E-M-F-System 14
2.4.2 Characteristics and utilization of stillages from bio-ethanol production 21
2.4.3 Characteristics and utilization of digestate from biogas production 28
2.5 Conclusions of biomass utilization in the E-M-F-System 31

3 Background and technical basis for the proposed E-M-F-System 33
3.1 Bio-ethanol production 33
3.1.1 Background and definition of bio-ethanol production technology 33
3.1.2 Classification and characteristics of basic bio-ethanol production process 40
3.1.3 Development of the technology 41
3.2 Biogas production 42
3.3 Bio-fertilizer production . 45
3.4 Conclusion of the technologies for this system 50
3.4.1 Full combination of these three processes 50
3.4.2 Problems of theoretical analysis 51

4 Laboratory research 53
4.1 Raw materials 54
4.1.1 Raw materials for anaerobic digestion experiment 54
4.1.2 Raw materials for aerobic composting experiment 56
4.2 Experimental reactors 57
4.3 Analysis methods 62
4.3.1 Anaerobic digestion analysis methods 62
4.3.2 Aerobic composting analysis methods 65
4.4 Results and analysis 66
4.4.1 Anaerobic digestion results and analysis from 1 l reactor ..67
4.4.2 Anaerobic digestion results and analysis from 60 l reactor 77
4.4.3 Aerobic composting results and analysis from 30 l reactor 79
4.4.4 Aerobic composting results and analysis from Dewar Reactor 85
4.5 Conclusions of the research 88

5 E-M-F-System assessment 91
5.1 Mass balance analysis of the E-M-F-System 95
5.1.1 Mass balance during the course of bio-ethanol production 95
5.1.2 Mass balance during the course of biogas production 100
5.1.3 Mass balance during the course of composting 103
5.2 Energy balance analysis of the E-M-F-System 108
5.2.1 Energy balance during the course of bio-ethanol production 109
5.2.2 Energy balance during the course of biogas production .. 116
5.2.3 Energy balance during the course of composting 120
5.3 CO2-eq. balance analysis of the E-M-F-System 129
5.3.1 CO2-eq. balance during the course of bio-ethanol production 129
5.3.2 CO2-eq. balance during the course of biogas production 133
5.3.3 CO2-eq. balance during the course of composting 134
5.4 Comparison of this E-M-F-System 136
5.5 Conclusion of the E-M-F-System balance analysis 141
5.6 Plants study in reference to the utilization of the E-M-F-System .. 145
5.6.1 E-M-F plants using grains as feedstock .. 147
5.6.2 E-M(-F) plant using sugar containing material as feedstock 154
5.6.3 Conclusion of the study of the E-M-F-System utilization plant 155

6 Tool box for the implication of the E-M-F-System 157
6.1 Purpose of the use of tool box .. 157
6.2 Basis of the tool box 158
6.3 Instructions for using the tool box 160
6.4 Manipulation of the tool box 161
6.5 Conclusion 164

7 Case study – implementation of the E-M-F-System in China 165
7.1 Situation and development of the E-M-F-System in China 165
7.2 Suitable input materials for this system world-wide 169
7.2.1 Suitable input materials for this system in China 169
7.2.2 Suitable raw materials for this system in other countries 171
7.3 Sweet potato as case study for this system 173
7.4 Conclusion of the E-M-F-System utilization in China 176
7.5 Case study of sweet potato in tool box .. 177
7.6 Conclusion 179

8 E-M-F-System - Innovation key points and conclusions .. 181
8.1 Consideration and improvements of the system . 181
8.2 Innovation key points 182
8.3 Conclusions 183

9 References 187
Appendix 203
Attachment . 219
Instruction of the tool box .. 231