Greenhouse Gas Life Cycle Assessment of Canola-Derived Hefa Biojet Fuel in Western
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Greenhouse gas life cycle assessment of canola-derived hefa biojet fuel in Western Canada by Debrah Zemanek A thesis submitted to the Department of Civil Engineering in conformity with the requirements for the degree of Master of Applied Science Queen's University Kingston, Ontario, Canada July 2018 Copyright c Debrah Zemanek, 2018 Abstract Biojet fuel represents the best short-term option for reducing greenhouse gas (GHG) emissions from the aviation industry. In the near term, biojet fuel is most likely to be produced via the hydroprocessed esters and fatty acids (HEFA) pathway. Canola is one of the most readily available feedstocks for HEFA fuel production in Canada, and interest has been shown in developing a domestic supply chain for biojet fuel. However, there is substantial variation in the reported emissions reductions that HEFA biojet from crop-based feedstocks can offer. The primary concern surrounds the inconsistent inclusion of land use change emissions. In addition to infrequently including land use change emissions, previous life cycle assessments (LCAs) of canola biojet fuel have not used Canadian production data, or have failed to examine the sensitivity of calculated emissions intensity to variation in many LCA parameters. In this thesis, the emissions intensity of canola biojet was calculated across four co- product allocation methods both with and without land use change emissions. Land use change emissions from potential grassland conversion on the Canadian Prairies were estimated using a soil carbon model. Finally, a sensitivity analysis on life cycle inputs and co-product allocation parameters was performed. Results suggested that without land use change, canola biojet fuel may provide emissions reductions of 35% to 54% compared to petroleum jet fuel. Land use change i has an overwhelming influence on biojet fuel emissions intensity, and its inclusion results in negative reductions in most cases. Emissions intensity and the sensitivity to parameter changes varied across allocation methods. This research points to the importance of standardized LCA methodology, and to the development of advanced biojet fuel production pathways that do not compete for arable land. ii Acknowledgments I would like to thank my supervisors, Dr. Pascale Champagne and Dr. Warren Mabee, for their guidance throughout my research. Their relevance in the renewable energy field is inspiring and I am grateful to have had their support and encouragement. I would like to acknowledge the financial support of Green Aviation Research and Development Network, Biofuel Net, and the Natural Sciences and Engineering Research Council of Canada. I am grateful to have been given the opportunity to participate in the Canadian Biojet Supply Chain Initiative, which has allowed me to gain an appreciation for the partnerships between academia, government, and industry that move great ideas forward. I would also like to thank the many people who helped my in my research through providing access to data and information on the canola biojet life cycle. Warren Ward from the Canadian Canola Council; Elwin Smith with Agriculture and Agri- food Canada; James Andersen from Honeywell UOP; Oskar Meijerink from SkyNRG and Jamie Stephen from Torchlight Biofuels. I'd also like to thank Dr. Neil Scott for his help and feedback on soil carbon modeling. From my frisbee throwing partners to my office coffee crew, I feel lucky to have made the friends I did in the Civil Engineering Department. I'm especially grateful to Shuang for knowing exactly when I needed a snack break, and for being my friend iii since day one of my time at Queen's. To my friends and family, I appreciate your love and support. And thank you, J.P., for giving me the reason I needed to pursue a Masters at Queen's. iv Statement of Co-Authorship This thesis is based on the following two manuscripts: Chapter 3 Zemanek, D., Champagne, P., Mabee, W. (2018). Review of Life Cy- cle Greenhouse Gas Emissions Assessments of Hydroprocessed Renewable Fuel (HEFA) from Oilseeds. Planned submission to Biofuels, Bioproducts, and Biore- fining. Chapter 5 Zemanek, D., Champagne, P., Mabee, W. (2018). Greenhouse Gas Life Cycle Assessment of Canola-Derived HEFA Biojet Fuel in Western Canada. Planned submission to Environmental Science and Technology. I was responsible for data collection and the design and implementation of the analysis, as well as the writing of all manuscripts. P. Champagne and W. Mabee assisted with the scoping of Chapter 3 and Chapter 5. All authors provided valuable assistance with manuscript editing. v Contents Abstract i Acknowledgments iii Statement of Co-Authorship v Contents vi List of Tables ix List of Figures xi Glossary xiii Chapter 1: Introduction 1 1.1 Background information . 1 1.1.1 Emissions from aviation . 1 1.1.2 Alternatives to petroleum-derived jet fuel . 3 1.1.3 Biojet fuel production in Canada . 6 1.1.4 Life cycle assessment . 8 1.2 Problem statement . 9 1.2.1 Land use change emissions . 9 1.2.2 Co-product allocation method . 10 1.2.3 Input data . 10 1.3 Thesis objectives and organization . 11 Bibliography . 13 Chapter 2: Background on HEFA 19 2.1 Introduction to the HEFA pathway . 19 2.1.1 Hydroprocessing reactions . 21 2.1.2 Pre-treatment . 24 2.2 Global status of HEFA production . 25 vi 2.2.1 hydroprocessed esters and fatty acids (HEFA) technology providers 30 2.2.2 Other BioSPK conversion pathways . 30 2.2.3 Summary of biojet production pathways . 32 2.3 Biojet adoption in Canada . 36 2.3.1 Feedstock availability in Canada . 36 2.3.2 Canadian Biojet Supply Chain Initiative (CBSCI) . 37 2.4 Conclusion . 38 Bibliography . 38 Chapter 3: Literature review 48 3.1 Introduction . 48 3.2 Review methodology . 49 3.2.1 Scope . 49 3.2.2 Analysis . 51 3.2.3 Parameters analyzed . 53 3.3 Results and Discussion . 56 3.3.1 Distribution of results across all scenarios . 56 3.3.2 Feedstock . 56 3.3.3 Co-product allocation method . 59 3.3.4 Land use change . 62 3.3.5 HEFA technology . 64 3.4 Conclusion and recommendations . 65 Bibliography . 67 Chapter 4: Land use change 73 4.1 Introduction . 73 4.2 Model description . 77 4.2.1 Data sources . 78 4.2.2 Carbon flows . 80 4.2.3 Model evaluation . 82 4.2.4 Results and Discussion . 84 4.2.5 Conclusion . 87 Bibliography . 88 Chapter 5: Life cycle assessment 96 5.1 Introduction . 96 5.2 Methods . 99 5.2.1 Life cycle assessment (LCA) in SimaPro . 99 5.2.2 Scope . 101 5.2.3 Co-product allocation . 106 5.2.4 Sensitivity analysis on inputs . 109 vii 5.2.5 Sensitivity analysis on co-product allocation parameters . 110 5.3 Results and Discussion . 111 5.3.1 Contribution analysis . 113 5.3.2 Sensitivity analysis . 114 5.4 Conclusion . 119 Bibliography . 120 Chapter 6: Conclusion 126 6.1 Thesis summary . 128 6.1.1 Recommendations and future work . 130 6.1.2 Contribution to engineering . 132 Bibliography . 133 Appendix A: Table of literature reviewed 136 Bibliography . 147 Appendix B: Soil carbon model 151 B.1 Decay of SOC pools . 151 B.1.1 Rate-modifying factors . 152 Bibliography . 154 Appendix C: Data sources and allocation methodology 155 C.1 Data sources for life cycle inputs . 155 C.1.1 Canola farming . 156 C.1.2 Oil extraction and upgrading . 160 C.1.3 Refining . 161 C.1.4 Transportation and distribution . 162 C.1.5 Combustion . 163 C.1.6 Displaced soymeal . 163 C.1.7 Displaced fuels . 168 C.2 Application of co-product allocation to calculation of emissions intensity169 Bibliography . 170 viii List of Tables 2.1 Physical and chemical properties of diesel and jet fuels . 20 2.2 Global operational and proposed HEFA facilities . 27 2.3 Biojet conversion pathways in the American Society for Testing and Materials (ASTM) review process . 33 3.1 Seed oil content by weight of oilseed feedstocks reported in the literature 53 3.2 Co-product allocation methods applied in GHG-LCAs of HEFA fuels 59 4.1 Inputs into soil carbon model . 79 4.2 Initial size and decay constants of soil organic carbon (SOC) pools . 81 4.3 Results of the soil carbon model across five amortization periods . 84 5.1 Inputs and yields of the canola HEFA biojet life cycle . 102 5.2 Co-product allocation methods compared in this study . 109 A.1 GHG-LCAs of HEFA fuels from oilseeds . 137 B.1 Monthly parameters in SOC model . 152 C.1 Properties of Western Canadian petroleum fuel inputs and jet fuel baseline . 159 ix C.2 Parameters of soybean and canola oil extraction and their co-product relationships . 165 C.3 Properties of petroleum fuels displaced in refining stage . 168 x List of Figures 1.1 Illustrative schematic of global emissions from aviation from 2005 to 2050 and the three environmental targets of the aviation industry . 3 2.1 Reactions involved in hydroprocessing canola oil feedstock . 21 3.1 Number of GHG-LCAs of HEFA jet or diesel from crop-based oilseeds by year of publication . 50 3.2 Well-to-wake (WTW) scope and associated life cycle stages of HEFA life cycle assessments (LCAs) . 51 3.3 The distribution of reported emissions intensities for HEFA diesel (n=69) and HEFA biojet (n=55) from scenarios that were reviewed within the literature. 57 3.4 Studies comparing the emissions intensity of HEFA fuels from different feedstocks . 58 3.5 Studies comparing the emissions intensity of HEFA fuels when different co-product allocation methods are applied . 60 3.6 Studies comparing the emissions intensity of HEFA fuels under differ- ent land use change assumptions .