Table of Contents
Acknowledgements……….i
Introduction and objective of the thesis…………...………...……….…..iii
Generalities and Motivation of the work……….………...iii
Objective of the work……….………..………v
Structure of the thesis……….………...…….vii
Introduzione………xiii
Generalità ………...……….……….xiii
Obiettivo del lavoro………..xvi
Struttura della tesi………vxii
1. The Problem for Controlling Environmental damages of the Energy Production Systems……….……….….……….1
1.1. Introduction………...1
1.2. Current World Energy Scenarios………..………3
1.2.1. The Future of Coal……….….………..……….5
1.3 The Harmful effects of Fossil-fuel Energy Conversion Systems on Human heath and the Environment………...………...10
1.3.1. Global warming and the greenhouse effect………...…….…..10
1.3.2. Acid rain………..…….……15
1.3.3. Particulate Matter (PM-10)……….…….……16
1.3.4. Mercury……….……….….…….16
1.4. The question for mitigating the environmental impacts of the energy production systems………...……17
1.5. Economic approaches to reduce emissions from energy production systems……….………..……19
1.5.1. Classification of market-based instruments……….….…..…..21
1.5.2. Carbon Pollution taxes………..……..….24
1.5.2.1. Application of the environmental taxes………….….…….…..26
1.5.2.2. Effects of the environmental taxes………..….….28
1.5.2.3. The future of environmental taxes: Kyoto, Application and Effects………...29
1.5.3. Tradable permits……….………..32
1.6. The Eco-efficiency approaches for energy production systems……….33
1.7. The Regulatory approaches for energy production systems………...34
1.7.1. Decarbonizing power generation……….36
1.7.2. Increase Energy efficiency………..36
1.7.3. Capture and storage of CO2 emitted from power-generation ………….37
References……….………40
2. CO2 Capture from fossil fuel power plants: Introduction of a model for assessing the energy requirements of CO2 chemical absorption capture technologies………..43
2.1. Introduction……….………43
2.2. CO2 capture……….………44
2.2.1 The basis for CO2 capture in fossil-fuel power generation………...44
2.2.2. State of the art of CO2 capture systems for fossil fuel power plants…...45
2.2.2.1 Post-combustion processes………46
2.2.2.2. Pre-combustion processes……….47
2.2.2.3. Oxy-Fuel combustion capture……….………..49
2.2.3. CO2 Capture technologies……….………..………...………..49
2.2.3.1. Separation with sorbents/solvents……….50
2.2.3.1.1 Chemical absorption………50
2.2.3.1.2. Physical absorption……….51
2.2.3.1.3. Dry solid absorption………...52
2.2.3.1.4. Physical adsorption………52
2.2.3.2. Cryogenic Separation………53
2.2.3.3. Membranes separation………..54
2.2.3.4. The new perspectives of CO2 separation technologies……….55
2.3. Proposal of a methodology for assessing the energy requirements of CO2 chemical absorption capture technologies………56
2.3.1. Methodology………57
2.3.1.1 Description of the chemical absorption capture process………58
2.3.2. Tools for a thermodynamic simulation of the capture process…………59
2.3.2.1. Flue Gas Pre-treatment……….59
2.3.2.2. Scrubbing/Stripper process……….………..60
2.3.2.2.1. Sensible Heat……….………60
2.3.2.2.2. The CO2 desorption energy………...…….…………61
2.3.2.2.3. Steam supplied for the stripping of CO2…………....61
2.3.2.3. CO2 liquefaction for transportation and storage….……….…..62
2.3.3. Main assumptions for the capture process……….…………..63
2.3.4. Application of the model to the Chemical CO2 absorption with an Aqueous Alkaline Solvent for flue gases……….………..65
2.3.5. Application of the model to the Chemical CO2 absorption with Aqua Ammonia solution………..………67
2.3.6. Application of the model to Chemical CO2 absorption with solid dry regenerable sorbent………69
2.3.6.1. Low temperature capture for dry regenerable sorbent in flue gases……….………..71
2.3.6.2. High temperature capture by dry regenerable sorbent in flue gases……….………..72
2.4.1. NOx Control technologies……….………..75
2.4.2. SO2 reduction technologies……….……….76
2.4.3. Particulate matter control technologies………….………...77
2.5 Conclusions……….……….78
References……….……….80
3. A Critical Overview of Advanced Clean Coal Energy Conversion Technologies……….85
3.1 Introduction………..85
3.2 Ultra-supercritical pressurized coal power plants USC……….………..89
3.3 Integrated Gasification combined cycle (IGCC)……….91
3.3.1 The modular perspective of IGCC………98
3.4. Pressurize fluid bed combustion (PFBC)……….………...99
3.5. Oxy-fuel combustion power plants (O2/CO2)……….………….……….102
3.6 Externally-Fired Combined Cycle (EFCC)………….………….……….106
3.7 Conclusions……….………….………..108
References………110
4. Methodological Instruments for Multidimensional Analysis of Energy Systems………113
4.1. Introduction………...113
4.2. Goals and boundaries definitions. Spatial and time scales………...116
4.3. Reductionist and Non- Reductionist Approaches……….117
4.3.1. Reductionist approaches………118
4.3.2. Non- Reductionist approaches………….………..119
4.4. Technical and Holistic Approaches………..119
4.4.1. Technical approaches……….………120
4.4.1.1. Historical review of the main technical analysis……….120
4.4.1.2. Second law efficiency in the technical analysis………..123
4.4.1.3. Technical approaches by means of suitable indicators……...124
4.4.1.4. A critical review of Environomic Analyses………125
4.4.1.4.1 Environmental cost………126
4.4.1.4.2. Different efforts to account for the environmental pollution costs …………..………127
4.4.1.4.3. Different efforts to account for the natural resources costs……….…….129
4.4.2. Holistic Approaches……….……..130
4.4.2.1. The use of indicators in the holistic approaches……….…….132
4.4.2.2. Emergy Analysis……….………….134
4.4.2.3. Life Cycle Assessments……….…………..135
4.4.2.4. A critical review Life cycle analyses………….………..136
5. The use of indicators into the energy analysis. Proposal of the Aggregated
Coefficient Methodology………...143
5.1. Introduction………...143
5.2. The aggregated multi-criteria assessment methods………..144
5.2.1. Some considerations about the application of the aggregated multi-criteria methods………146
5.3. Proposal of the Aggregated Coefficient Methodology for the Analysis of Power Generation Systems (ACP)……….……….149
5.4. Description of the different type of indicators used in the analysis………..151
5.4.1. Thermodynamic indicators………153
5.4.2. The environmental indicators………155
5.4.2.1. Resources indicators………155
5.4.2.2. Pollution indicators……….156
5.4.3. The economic indicators………157
5.5 Application example for the ACP Method………158
5.5.1. Weight theory……….160
5.5.2. Results and Conclusions………160
References………164
6. Proposal of a synthetic utility function for the analysis of energy systems…..167
6.1. Introduction……….……..167
6.2. Proposal of a Synthetic utility function for the analysis of energy systems….…168 6.3. Application of the utility function Ψfor the optimization of thermal systems….170 6.4. The quest of taking the environment into account; Ψp function………..178
6.5. The fundamentals of the pollutant emission factor βp……….180
6.5.1. Definition of the environmental reference state……….181
6.5.2. Pollutant emission factor βp………..183
References………186
7. Application of the Composed Utility FunctionΨΨΨΨp………...………...189
7.1. Introduction………..189
7.2. Conventional steam power plant ………..190
7.3. Natural Gas cogeneration power plant……….192
7.4. Application of the composed utility function Ψp as a synthetic indicator……...193
7.5. Parametric studies……….197
7.5.1. Evaluation of retrofitting an end-of-the-pipe CO2 capture technology by means of the synthetic indicator Ψp………198
7.5.2. Effect on the pollutant emission factor βp of the diverse compositions of the exhaust gases in the evaluation of the function Ψp……...………202
7.5.2.1 Analysis of the combustion products…………..……….202
7.5.2.2. Sensitive analysis of βp in a coal-fired power plant………...204
7.6 Conclusions………206
8. Conclusions and suggestion for further works………...…………209 8.1. Summary and conclusions………209 8.2 Future perspectives………212 Appendix A. Some consideration about thermodynamic indicators for renewable energies...215 A.1. Definition of the First-Law efficiency for renewable energies………215 A.2. Definition of the Second-Law efficiency for renewable energies….…………...220 References………223 List of symbols………225
