This thesis examines the role of Sustainable Aviation Fuels (SAFs) in advancing the sustainability goals of the aviation industry, focusing on their environmental impacts, economic feasibility, and compatibility with existing aircraft performance. The research primarily involves a comprehensive literature review and analysis of existing studies to evaluate the potential of SAFs to reduce carbon emissions significantly—up to 80% relative to conventional jet fuels depending on the feedstock and processing methods used. The economic analysis reveals that while SAFs are currently more costly than traditional fuels, regulatory incentives and technological advancements could decrease these costs, making SAFs more competitive. Performance-wise, SAFs are shown to be viable "drop-in" options, requiring minimal modifications to aircraft or fuel infrastructure, thus facilitating easier adoption across the industry. The study concludes that despite the challenges, SAFs are indispensable for the aviation sector’s transition towards net-zero emissions. It emphasizes the need for enhanced collaboration among governments, industry stakeholders, and researchers to scale production and integrate SAFs into the global fuel mix effectively.

Previous studies have claimed a deadlock between fuel producers, airlines and policymakers when it comes to the market uptake of Sustainable Aviation Fuel (SAF). This report investigates the market from a stakeholder perspective, including producers, distributors, purchasers and logistic holders. Obstacles in terms of market maturity are identified as mainly the price gap between Conventional Aviation Fuel (CAF) and SAF. This is due to many things, whereas one being the detachment between travellers and the usage of SAF. It is also the current blend restriction of a maximum of 50 %, as well as extensive and expensive certification processes. Currently, there are few, but a lack of policies and incentives directed towards SAF and a lack of coherency between those that exist and are being implemented. Stakeholders agree that there is a need for developing these, as well as a need for additional financial support during stages of developing production facilities. When it comes to procurement of SAF, stakeholders agree upon that flexibility within different areas are advantageous for the market uptake of SAF, and in most regards, the procurement made by Swedavia is indeed flexible. An important aspect identified in the analysis of Swedavia’s procurement is the use of a business model which reduces the price gap between CAF and SAF for airlines and enabling Swedavia to claim the CO2 reduction of corporate travel. Multiple corporates joined the previous procurement of SAF for corporate travel, and Swedavia holds great opportunities to continue to contribute to the market uptake of SAF by expanding the concept. Multiple opportunities also lie in expanding the business concept to reach all travellers. Concluding, it is established that the current route, mainly referring to the procedure of procurement, is effective and carries great opportunity for further implementation and development. / <p>2021-06-04</p>

Baigiamajame magistro darbe yra apžvelgti aviacinių degalų sąnaudų mažinimo būdai Lietuvos oro linijose. Apžvelgiama pasaulinė bei Lietuvos aviacijos rinka bei aviacinių degalų kainų didėjimo įtaka jai. Aviacinių degalų sąnaudų mažimo būdų paieška ir įvertinimas apima skrydžių planavimą, skrydžių vykdymą, techninę priežiūrą. Taip pat vertinama lenktų antsparnių sumontavimo lėktuvuose įtaka degalų sąnaudoms. Atliekami eksperimentiniai skaičiavimai atlikto darbo tikslingumui bei sąnaudų mažinimo būdų teikiamai naudai įvertinti. Darbą sudaro 6 dalys: įvadas, tyrimo objektas ir problemos aptarimas, analitinė-metodinė dalis, eksperimentinė-tiriamoji dalis, išvados ir siūlymai, literatūros sąrašas. Darbo apimtis – 73 p. teksto be priedų, 24 iliustr., 37 lent., 23 bibliografiniai šaltiniai. / In this concluding masters work was overlooked the means of decreasing expenditures in Lithuanian airlines. There is also given an overlook of World‘s and Lithuania‘s aviation markets and the impact of rising aviation fuel prices to them. The search and evaluation of means of decreasing aviation fuel expenditures involves areas of: flight planning, performing the flights and technical maintenance. The expected results on the fuel expenditures of mounting blended winglets is also assessed. Experimental calculations also evaluates influence and benefits of applying fuel saving means. This work consists of six parts: introduction, the reserch’s object and discussion of the problems, literary analysis, experiments and questionnaires, conclusions and suggestions, literary list. Thesis consist of: 73 p. text without appendixes, 24 pictures, 37 tables, 23 bibliographical entries.

A highly selective eggshell Fischer-Tropsch catalyst has been fabricated via interaction of hydrophobic and hydrophilic molecules on thermally treated silica gel. The physical interactions of the mesoporous silica support and the effect of catalyst preparation conditions on the performance of the cobalt/SiO2 were explored. It was found that dispersion and performance of the FT cobalt/SiO2 catalyst were significantly affected by the preparation technique used. In this study we focus on two key variables: the solvent used during the precursor loading and the calcination atmosphere. Silanol groups on the silica surface and near-surface regions can alter morphology and dispersion of the supported active metals. Solvents used for precursor such as water or alcohol attach to these silanol sites in specific configurations and compete with metal salts during ion exchange and adsorption. By fine tuning the solvent attachments on heat treated silica we have fabricated a cobalt/silica catalyst with high dispersion and low metal loads. Additionally, since silica has affinity for both polar and non-polar molecule depending on the surface conditions; this property has been exploited in preparing an engineered eggshell profile. This together with simultaneous calcination/ reduction in a dynamic hydrogen environment has been shown to further enhance dispersion and reducibility. Characterization techniques including BET, XPS, XRD, H-chemisorption and FTIR were employed. Catalyst activity, product selectivity, distribution and conversion were studied using a bench scale fixed bed reactor fitted with a GC/MS instrument.

The recent spikes in oil prices have spurred an already bullish demand on biofuels as a source of alternative energy. However, the unprecedented price records set simultaneously by staple food have raised high concerns about potential impacts of biofuels on the global agricultural landscape as fuel and food markets are being inextricably coupled. The revival of interest in the Fischer-Tropsch (FT) process comes into full force since it offers a promising way to produce carbon-neutral liquid fuels which are readily usable with today's existing infrastructure. The FT synthesis offers the possibility of using crop waste as feedstock instead of the crop itself thus avoiding the risk of further straining water and land resources while helping to alleviate the national energy bill and to achieve independence from foreign oil. As the airline industry is the hardest-hit sector with fuel jumping ahead of labor as the primary cost item, this thesis investigates the prospects of the FT process to transform sugar cane waste (namely bagasse, tops and green leaves) and landfill gas in order to produce kerosene (C12H26) as jet fuel for civil aviation. Established chemical correlations and thermodynamics of chemical reactions are used to assess the water footprint inherent to kerosene production using the above feedstocks at optimal conditions of temperature, pressure, catalyst and reactor type. It has been estimated that 9 to 19 gallons of water are needed for every gallon of kerosene produced. In addition, for the case of sugar cane, less land area per unit energy is required compared to ethanol production since all non-food waste of the plant can be used to produce FT fuel as opposed to ethanol which would utilize only the sugar (food) portion of the plant. This translates into a much lower water footprint for irrigation and consequently a lower water footprint overall.

No description available.

Recent policy changes have shifted research and development to pursue technology that promotes a circular economy and net zero emissions by 2050. Current research is actively developing “drop-in” sustainable aviation fuels (SAF) that reduce emissions and are compatible with modern-day jet engines, mimicking conventional jet fuel's physical and chemical properties. While ensuring sustainable engine performance and operability using drop-in SAF is critical, several challenges remain in the economic outlook of SAF production. Biogas reforming and Fischer-Tropsch synthesis (FTS) can be used in series to convert landfill gas to SAF; however, novel design approaches must be considered to alleviate capital and operational expenses. This study analyzes the feasibility of continuous conversion of purified landfill gas to SAF via biogas reforming and FTS to determine the production and economic viability using a laboratory-scale reactor system. The system will then be assembled on a mobile trailer so that performance can be assessed onsite and case-by-case with respect to the composition of the landfill’s emissions.

<div>Determination of the chemical composition of liquid transportation fuels emerged as a novel and important field of study after the introduction of advanced analytical instruments, which are capable of very detailed chemical analyses of complex mixtures. Aviation fuels make up a crucial portion of liquid transportation fuels. There are several significant challenges in the field of aviation fuels, including the development of optimal analytical methods for the determination of the chemical compositions of the fuels, fuel properties measurements, and correlations between fuel properties and chemical composition. This dissertation explores possible correlations between fuel chemical composition and its properties and proposes novel approaches. First, a detailed description of a method for the determination of the detailed chemical composition of all middle distillate fuels (diesel and aviation fuels) is presented. Second, the density was correlated to fuel composition. Additionally, the approach of measuring the density, the hydrogen content, and the carbon content via a GC×GC-FID was introduced. Lastly, it was discovered that minute differences in chemical composition can influence fuel properties. This finding is described in the last chapter, where three HEFA samples were investigated. </div>

Avec la nouvelle génération d'avions composites, une attention est portée sur les systèmes de carburant vis-à-vis de la prévention des décharges électrostatiques (ESD) durant les phases de remplissage des réservoirs. La plupart des travaux réalisés en aéronautique a été menée sur des réservoirs métalliques. Toutefois, l'introduction des matériaux composites a soulevé de nouvelles interrogations, puisque ces matériaux peuvent avoir un comportement différent des métaux vis-à-vis de l'électrisation par écoulement, qui justifient pleinement de nouvelles analyses. Afin de définir correctement les structures des réservoirs et leur protection contre les risques ESD, il est crucial de comprendre comment un empilement complexe de matériaux se comporte en termes de création de charge lorsque ces matières sont en contact avec un carburant d'avion. La structure de ces matériaux et leurs propriétés électriques contrôlent le potentiel électrique atteint dans le réservoir à travers un équilibre entre la production, l'accumulation et la fuite des charges électriques. Ce potentiel peut dépasser le point d'éclair du mélange air/vapeurs de carburant et provoquer une inflammation. Diverses mesures de protection peuvent être adoptées pour contrôler ce phénomène, comme utiliser des additifs antistatiques dans les carburants, des réservoirs métalliques à la masse ou encore des réservoirs faits de matériaux non métalliques mais ne favorisant pas l'accumulation de charges. C'est principalement en réponse à cette dernière solution que ce travail est orienté afin de guider vers le choix optimaux des matériaux et une meilleure définition des structures du réservoir. / With the new generation of composite aircrafts an attention is carried out on fuel systems with respect to prevention of electrostatic discharges (ESD) during the filling phases of the tanks. Most of the work realized in aeronautics (during the 60's) was conducted on metallic fuel tanks. However, the introduction of composite materials has raised new questions, since those materials can have a different behavior than metallic ones with respect to flow electrification, which fully justify new analyses. In order to properly define the tank structures and their protection against ESD hazards, it is crucial to understand how a complex stack of materials (conductive or not, multilayered or homogeneous, painted or not) constituting a fuel tank behaves with respect to the mechanisms of charge creation by flow electrification when these materials are in contact with aviation fuel. The structure of these materials and their electrical properties control the electric potential reached in the tank through a balance between the production, accumulation and leakage of the electrical charge. This potential may exceed the flash point of the fuel vapors/air mixture and induce ignition. Various protective measures can be adopted to control this phenomenon such as using antistatic additives in the fuels, lowering the rates ofthe fuel injection inside the tank, using only bonded metallic tanks or tanks made of non-metallic materials which do not favor charge accumulation or local charge trapping. It is majorly in response to the latter solution that this work is oriented in order to guide optimum choices of materials and a better definition of the tank structures.

Sweden has an ambitious goal that the country will be carbon neutral by 2045, where this includes all sectors, including transportation and thus aviation. The aviation sector is an important part of the transportationsystem where the development of society has become dependent on this transportationalternative. In 2017, the aviation accounted for six percentof Sweden’s carbon dioxide emissions, one percentfrom domestic flightsand five percentfrom international flights. In order toreduce these emissions, active work is ongoing for a transition where domestic aviation will be fossil-free in 2030 and all departures from Sweden to the international market will be fossil-free in 2045. Aviation has historically had a strong connection to fossil fuels and environmentally friendly alternatives have not yet managed to compete in the market.This study has investigated how sustainability can be a central part of the business model and how these should be adapted as part of the work to a fossil-free business, as well as the role of sustainable aviation fuels (SAF) and policy instruments in the energy transition. By mapping important aspects for sustainable business models, market potential for SAFand the development of new policy instruments,this study contributes with a systems perspective on the Swedish aviation industry's energy transition. The delimitationofthe study has been the Swedish market with focus on actors with their operations in Sweden. The methodologyhas consisted of a literature study, an interview study with 11 actors in the Swedish market and a case study on the airline corporationBraathens Regional Airlines (BRA), which mainly operates domestic flights in Sweden with Bromma as their headquarters.The results showed that there are three areas that are important in the work with sustainable business models, three areas for the market potential for biofuels and four areas for policy instruments. In the development of sustainable business models, cooperation and co-financing are seen as central aspects for an effective transition with better risk distribution. Transparent sustainability work, climate calculations and biofueltickets are considered important tools to increase the customer's understanding of the company's transition towards a sustainable future. The public's lack of knowledge regarding the energy transition for aviation is considered an obstacle towards increased sales of biofuel tickets, which also creates flygskam and avoidance of aviation as a means of transportation. The biggest obstacle towards an increased share ofSAFon the Swedish marketis mainly considered to be the lack of Swedish production.Increased production would mean large investment costs and high risks, which means that co-financed projects are proposed to overcome this obstacle. Biomass as a raw material and how it is used and classified in the EU is also an obstacle towards increased use. Current policy instruments show that the reduction obligation is a positive addition, but the penalty fee needs to be raised above the price of SAF.The EU taxonomy can also play a decisiverole in the transitionprocess, as the classification of biomass and bioenergy can affect interest and willingness to make new investments.In addition, travel policies of companies are an obstacle when they prohibit travel by aviation.Finally, policy instruments are needed that favor Swedish production of SAF, where the industry sees great opportunities in both technology and raw materials, but lack of political initiatives.