Search

The spray characteristics of standard and alternative aviation fuels created by a hybrid pressure-swirl airblast (HPSA) atomizer were investigated at conditions corresponding to engine cold start f...

The production of biomass‐based sustainable aviation fuel (SAF) is gaining traction to reduce the carbon footprint of the aviation sector. We performed a techno‐economic analysis to estimate the break‐even price and life cycle carbon emissions of the SAF derived from carinata (Brassica carinata) in the Southeastern United States. Carinata has the potential as a feedstock for SAF production in the selected region due to higher yield, low fertilizer use, co‐product generation (animal feed, propane, and naphtha), and compatibility with current farming practices. The system boundary started at the farm and ended when the SAF is delivered to an airport. Without co‐product credit or other subsidies such as Renewable Identification Number (RIN) credit, carinata‐based SAF was more expensive ($0.85 L−1 to $1.28 L−1) than conventional aviation fuel ($0.50 L−1). With co‐product credit only, the break‐even price ranged from $0.34 L−1 to $0.89 L−1. With both co‐product and RIN credits, the price ranged from ‐$0.12 to ‐$0.66 L−1. The total carbon emission was 918.67 g CO2e L−1 of carinata‐based SAF. This estimate provides 65% relative carbon savings compared with conventional aviation fuel (2618 g CO2e L−1). Sensitivity analysis suggested a 95% probability that relative carbon savings can range from 61% to 68%. Our study indicates that carinata‐based aviation fuel could significantly reduce carbon emissions of the aviation sector. However, current policy support mechanisms should be continued to support manufacturing and distribution in the Southeastern United States.

A novel integrated biorefinery system consists of (1) pyrolysis of biomass into gas, bio-oil and char; (2) bio-oil hydrodeoxygenation and hydrocracking (hydroprocessing) producing renewable jet fuel and small chain alkanes; (3) alkane steam reforming and pressure swing adsorption (PSA) producing green hydrogen and carbon monoxide; (4) mixed ionic electronic conducting membrane (MIEC) splitting high pressure superheated steam (HPSS) into green hydrogen and oxygen; and (5) combined heat and power generation (CHP) using pyrolysis gas and carbon monoxide from PSA as fuel with oxygen from MIEC, to fulfil the demand for HPSS and electricity. Comprehensive mathematical models are shown for the design simulation of the integrated system: (1) kinetic model of biomass pyrolysis at temperature 300−500 °C, (2) stoichiometric chemical reaction model of hydroprocessing, (3) renewable aviation fuel property correlations from its chemical compositions for the ASTM D7566 standard, (4) mass and energy balance analyses of the integrated biorefinery system. Economic value and overall avoided environmental and social impacts have been analysed for sustainability. The ratios of mass and energy flows between biomass, bio-oil, renewable jet fuel, CHP-fuel, char and hydrogen are 1.33:1:0.45:0.3:0.16:0.05 and 1:0.82:0.7:0.41:0.14:0.22, respectively. For 10tph bio-oil processing, the capital cost of the plant is $13.7 million, the return on investment is 19% and the cost of production of renewable jet fuel is $0.07/kg, which is lower than its market price, $0.27/kg. This production can curb 108 kt CO2 equivalent and 1.44 PJ fossil energy per annum. To enable the biorefinery simulation, user-friendly open-source TESARREC™ https://tesarrec.web.app/sustainability/bio-jet-fuel has been developed.

It has been claimed that hydrogen aviation may still significantly contribute to global warming through jets contrails, as hydrogen jets produce more contrails than jets fueled with kerosene. The claim, based on modeling exercises, can be tested via the Covid-19 experiment. Since March 2020, air traffic has been severely disrupted because of the pandemic. This has been true especially in Australia, the hermit country where citizens have been practically prevented from leaving or returning, with international air travel dramatically reduced. Analysis of the surface temperature data about international airports and air traffic from Australia provides the opportunity to test one of the hypotheses formulated about jet contrails' contribution to global warming. It is shown as opposed to previous claims, jet contrails are not responsible for reducing the difference between the maximum and minimum daily temperatures close to airports. Compared to the last 9 months of 2019, with air traffic normal, during the last 9 months of 2020 of highly disrupted flights, the difference in between the maximum and minimum temperatures in Sydney and Melbourne airports, has not been larger, but smaller by about 1 °C. The reduction in the difference between temperatures has been also smaller in Brisbane airport, but only at about 0.22 °C. We conclude as the claim adoption of hydrogen as an aviation fuel may produce global warming through the contrails mechanism is likely wrong. The contrails effect is everything but well understood and quantified with accuracy, and poorly represented in climate models. The contrails contribution to global warming is expected to be minor, and it should not void the value of hydrogen as a future renewable fuel free of CO2 emissions.

Background Continued progress towards reducing greenhouse gas emissions will require efforts across many industries. Though aviation is estimated to account for modest portions of global greenhouse gas emissions, these shares may grow as the industry expands. The use of biomass- and crop-based sustainable aviation fuels can help reduce emissions in the industry. However, limited feedstock supplies are a barrier to increased use of these fuels. This study examines the potential supply of feedstock from oilseeds and farmer willingness to produce oilseed crops under contract for sustainable aviation fuel production with a focus on canola and similar oilseed feedstocks (e.g., rapeseed). Stated-choice survey data is used to examine the contract and crop features that drive contract acceptance in six states located in the U.S. Great Plains and Pacific Northwest and then acreage supply curves are estimated for canola using secondary data. Main findings The estimated number of acres supplied under contract varies considerably across states and scenarios. Relatedly, estimated supply curves exhibit high degrees of price responsiveness. Of the states analyzed, oilseed acreages supplied under contract are generally found to be greatest in Kansas and North Dakota. Conclusions Results suggest that in the absence of favorable contract and crop scenarios canola and other oilseed prices will need to considerably increase from typical levels to induce higher levels of supplied acres. The presence of crop insurance, shorter contract lengths that provide cost sharing and the availability of particular crop attributes are shown to diminish the need for higher canola and other oilseed prices.

During the COVID-19 pandemic period, all airlines experienced a severe impact and the route operating cost is very susceptible to the impact of flight duration and aviation fuel prices. This paper analyzes the operation performance of Beibu Gulf airlines (low cost airline company) with data envelopment analysis CCR model in pre-COVID-19 pandemic period. Under the domestic vigorous promotion of tourism development and people's huge demand for travel, the airlines in mainland China continue rapid development, which accelerates the emergence of local airlines other than the four major airlines and leads to increasingly fierce operation competition in the civil aviation industry. Behind the competition among airlines, the operational performance of airlines can best reflect the company's development status. In this context, airlines should choose appropriate operational strategies to strengthen its competitiveness and operational capabilities. The DEA model is a mature input-output research tool, and there have been many studies related to operational performance of the aviation industry. By using Data Envelopment Analysis (DEA) solver software, the input and output indicators from 2017 to 2019 are analyzed. Preliminary results show that routes and oil price factors have not reached effective status. Beibu Gulf Airlines gradually shifts to low-cost mode, the faced challenges are as follows: 1. The competition among domestic low-cost airlines; 2. The current poor overall service quality of low-cost airlines as evaluated by customers; 3. How to arrange routes, flight, service strategy, etc. Airbus uses enhanced aviation systems for this series of aircraft to improve the overall reliability of the aircraft, reduce maintenance and spare parts costs, thus helping airlines greatly reduce maintenance costs, which is very beneficial to low-cost airlines. Based on this, this paper puts forward some suggestions, such as optimizing routes, developing feeder flights in second tier cities of popular destinations, controlling fuel costs, making low-cost aviation fuel reserves, reducing the weight of passengers' carry-on luggage or charging additional baggage charges.

Bio-aviation fuel to satisfy ASTM (American Society for Testing and Materials) specification was prepared through the stable operation of bio-aviation fuel manufacturing facility scale-expanded up to the production of bio-aviation fuel for turbine engine test. First, powder-typed 1.0 wt% Pt/Al2O3 and 0.5 wt% Pt/zeolite catalysts, respectively applicable to the hydrotreating and upgrading processes, were prepared and then their performance was evaluated in laboratory scale reactor. Thereafter, pellet-shaped 1.0 wt% Pt/Al2O3 and 0.5 wt% Pt/zeolite catalysts were prepared and applied to a bench-scale hydrotreating process and an upgrading process reactor, applied in the catalytic processes to prepare bio-aviation fuel. At this time, reaction characteristics under various operating conditions were investigated along with their catalytic performance evaluation. Stable long-term operation based on optimal reaction conditions, obtained in bench-scale reactor was performed using the hydrotreating process and the upgrading process reactors in a pilot-scale bio-aviation fuel manufacturing facility to continuously operate during a long time under optimal reaction conditions controlled, and then synthetic bio-crude oil including bio-aviation fuel composition was prepared. Through the separation and purification process that can selectively obtain bio-aviation fuel components, bio-aviation fuel conforming to ASTM specification standards was produced from the synthetic bio-crude oil obtained through combined hydrotreating-upgrading process.

The potential to recover waste heat from the exhaust gases of a turboprop engine and produce useful work through an Organic Rankine Cycle (ORC) is investigated. A thermodynamic analysis of the engine’s Brayton cycle is derived to determine the heat source available for exploitation. The aim is to use the aircraft engine fuel as the working fluid of the organic Rankine cycle in order to reduce the extra weight of the waste heat recovery system and keep the thrust-to-weight ratio as high as possible. A surrogate fuel with thermophysical properties similar to aviation gas turbine fuel is used for the ORC simulation. The evaporator design as well as the weight minimisation and safety of the suggested application are the most crucial aspects determining the feasibility of the proposed concept. The results show that there is potential in the exhaust gases to produce up to 50kW of power, corresponding to a 10.1% improvement of the overall thermal efficiency of the engine.

In civil aviation primary focus is on the quality of fuel filled in the aircraft fuel tanks, as one of the components of flight safety ensuring. The introduction of digital technologies and trends in automation, digitalization of modern civil aviation aircraft provision are becoming the basic tool for civil aviation refueling complexes in terms of ensuring flight safety of civil aviation aircraft. This article considers the processes of airfield control that take place in the stationary operating conditions of refueling complexes of civil aviation airports as Markov processes and studies the approaches to their mathematical modeling. The authors claim that in the case of disruption, there is a transition from Markov to Poisson processes, which mathematical description requires different approaches. The practical application of these statements is obvious in the study of the states probabilities value as a function of time t. For practical purposes, the limiting probabilities of states at t→∞ are of interest. This creates conditions for entering new variables, such as performance and others. Thus, Markov processes allow us to apply the mathematical apparatus of operations research, where the system of states is transformed into the queuing system. To maintain Markov processes, the authors suggest giving due consideration to the objects and technical means of airfield control functioning including: retrofitting of filling points and refueling facilities with closed sampling systems, operational measurement of aviation fuel quality indicators and registration of their results, automated monitoring of filter elements condition while refueling and its blocking in the case of stochastic differential pressure beyond the specified indicators. A special novelty is the view on the measuring process of the aircraft refueling operations as an integral part of airfield control, using block chain technologies as an advanced application of Markov chains.

The use of fossil fuels in aircraft over the last few decades has driven several studies on health effects due to occupational exposure. Relatively recently, alternative fuel types have emerged, but their implications on the health of exposed workers have not attracted proportional attention. In our paper, we review both academic and gray literature about the health risks related to exposure to jet and alternative fuels. The literature suggests that, although the health effects on workers exposed to conventional fuels are concerning, there is no universally accepted dose–response relationship. The limited current research with animals on alternative fuels indicates that these fuels have not resulted in a reduction of health risks. Overall, it seems that, while aviation fuels are tested for efficiency and lower emissions, studies on health impacts in an occupational context have not been a priority. As occupational exposure to aviation fuels might increase due to the growth of the aviation industry, it is essential to conduct further research on the effects of exposures to both conventional and alternative aviation fuels and ensure that the latter do not pose the same risks or even greater ones than those of conventional fuels.

The increasing stipulate for energy demand has necessitated the progress to alternative renewable energy. Aviation fuel is the main source for aircraft engines to progress from one place to another. The objective of the study potentiates the use alternative, renewablefuels which accomplish better than aviation fuel in terms ofpremiere and intended concert. Considering aviation fuel in terms of premium and intended concert at different proportions of fuel blends with biofuel such as ethanol, methanol was analyzed. The conventional fuel mixed with oxygenated fuel in the ratios of 10%, 20%, 30%, and 40% by volume basis.These fuel blends were used to determine experimentally the effects of fuel properties and characteristics. Comparing the results and properties of fuel blends with aviation fuel has been used in transportation, energygeneration and combustion performance. By influential of fuel blends properties which consign the performance analysis and its significance. The fuel parameters such as density, viscosity, refractive index, vapour pressure, flash point, and calorific value were tested by utilizing with the accurate equipment. For analysing blended fuels various testing equipment is used mainly to find out fuel efficiency. As a result, these fuel blends intricate the efficient functions to perform for the minuscule flying machine. The radio-controlled plane functions were tested at high altitude, speed and spin with these blended fuels. The fuel combustion as a result of burnt gas pollutants traces were recorded by using the exhaust gas analyzer.

Recognition of the adverse impacts of climate change has led to interest in a transition to renewable, carbon-neutral energy and fuels. Ammonia has been proposed as a renewable transportation fuel, a medium for local energy storage, and a means for long-distance renewable energy transportation. We provide a perspective on the future use of ammonia as a transportation fuel. Ammonia poses health and safety concerns and ensuring safety for widespread distribution and consumer use would be challenging. Ammonia has a low energy content and is difficult to ignite, making it a relatively poor fuel in internal combustion engines. Engine unburnt ammonia emissions reported in the literature are approximately two to three orders of magnitude greater than Euro IV tailpipe limits and point to severe challenges in meeting emission regulations. Ammonia can be used in solid oxide fuel cells, but these operate at high temperatures (700–800 °C) and are not well suited for road vehicles. Proton exchange membrane and direct ammonia alkaline membrane fuel cell systems operate near room temperature and can use ammonia directly or indirectly (after conversion to H2) however poisoning and durability is problematic. Therefore, the expected use of ammonia as fuel for road transportation is very limited. With its low energy content, ammonia is not a viable aviation fuel. Substantial use of ammonia in rail applications seems unlikely given the advanced state of electrification and challenges associated with ammonia noted for road transport, many of which would also apply to rail. In contrast, the future use of ammonia as fuel in ocean-going ships seems feasible. Many large ports are already equipped to handle ammonia, storage volume and weight are not pressing issues for large ships, safety issues would be addressed with trained crews, and emission standards are less stringent. Ammonia might also find use as an energy carrier for transport of renewable energy between regions which would be a synergy with its use as a marine fuel.

It has been shown that the studied petroleum products (kerosene and gasoline) contain microflocules of heterogeneous microbial biofilms, the cells of which are integrated into a polymer matrix containing acidic polysaccharides. Thirteen bacterial strains were microbiologically isolated from petroleum products, and their taxonomy was identified by the 16S rRNA sequence. Kerosene was characterized by a diverse bacterial composition including the following genera: Sphingobacterium, Alcaligenes, Rhodococcus and Deinococcus, while gasoline bacterial community included only two genera: Bacillus and Paenibacillus. Representatives of the Deinococcus genera capable of growing on the hydrocarbons were isolated from fuels for the first time. The strains isolated from gasoline (Bacillus safensis Bi13 and Bacillus sp. Bi14) proved to be the most effective biodegraders of all n-alkanes, isoalkanes, cycloalkanes, alkenes and aromatic hydrocarbons, whereas the kerosene strain Rhodococcus erythropolis Bi6 effectively decomposed n-alkanes and trimethylbenzene. Both types of petroleum products contained hydrocarbon-oxidizing communities, some members of which were more active in the biodegradation of hydrocarbons, while others were capable of producing biosurfactants and had either emulsifying activity (Deinococcus sp. Bi7) or cell wall hydrophobicity (Sphingobacterium sp. Bi5 from kerosene; Bacillus pumilus Bi12 from gasoline) significantly higher than the average level. The indicated properties of the studied strains make them promising for use in bioremediation. biodegradation, petroleum products, hydrocarbon-oxidizing bacteria, bio-surfactants The work was carried out within the framework of the state assignment of the Ministry of Science and Higher Education of the Russian Federation (topic no. 10.5422.2017/8.9.). Investigation of microbial potential in the use hydrocarbons was supported by the Russian Foundation for Basic Research (RFBR), contract no. 18-29-05067. Physicochemical research was performed within the framework of the state assignment to the TIPS RAS

The article discusses the elements of creating and implementing innovative technological equipment for the refueling complex laboratory «TZK» - a single integrated quality management system for aviation fuel supply for civil aviation aircraft, by increasing the system's capabilities by adding new components. The introduction of digital technology, tools, industry 4.0 and trends of automation, digitalization, digitalization of modern aviation fuel aircraft HA become a basic tool of refueling complexes HECTARES in the security of aircraft, civil aviation, which is especially important in high intensity operations. The article presents a theoretical preliminary research of the issue before the following research from the theoretical level to the practical level of problem solving.

This paper analyses the performance of commodity cross-hedging of aviation turbine fuel (ATF) price exposures with crude oil and Brent oil futures for the Indian aviation industry. Models that were estimated using three alternative techniques of ordinary least squares (OLS), error correction models (ECMs), and autoregressive conditional heteroskedastic (ARCH) showed that Brent crude oil futures had the highest cross-hedging efficiency. Further, the variances of the profit and loss (P&L) series and value at risk (VAR) associated with alternative hedging strategies – including a composite hedge of crude oil and Brent oil futures – showed that although hedging is redundant for domestic operations, composite hedging for imported ATF prices could substantially lower the VAR compared to all other alternatives from imported and domestic operations.

The article analyzes the main information automated control systems for refueling complexes, based on this analysis, the problems of the airport ground handling functioning are identified, the main of which are the inefficiency of managing stochastic processes that occur in failure situations, as well as the lack of automated control systems for the level of purity of aviation fuel from mechanical impurities and water. The way to upgrade Groundstar Inform GmbH - a single integrated airport management system by increasing the capabilities of the system by adding new components is proposed. A solution to the problem of multi-resource planning of aircraft refueling in high-intensity flight conditions, including failure situations, based on intelligent simulation and resource management is proposed. As well as from the point of view of optimizing the solution of business process objectives the development of planning algorithms using the mathematical apparatus of fuzzy modeling and control, fuzzy sets and fuzzy logic underlying the intelligent modeling of processes is proposed. The concept of an adaptive information management system of technological processes of a refueling complex for monitoring the purity of jet fuel, based on dynamic on-line monitoring of the existence of mechanical impurities and water is introduced. The article examines the elements of creating a "Smart Refueling Complex", in which intelligent business processes are combined into one whole due to the use of "smart" operational processes and technological equipment. The introduction of digital technologies, "industry 4.0" tools and trends in automation, digitalization and digitalization of the modern aviation fuel supply for civil aviation is becoming the basis of the digital economy of civil aviation refueling complexes.

Aviation industry is considered one of the contributors to atmospheric CO2emissions. It is forced to cut off carbon dioxide emission starting 2020. Current trends in bio-jet production involve mega projects with million dollars of investments. In this study, bio-jet fuel production by blending bio-diesel with traditional jet fuel at different concentrations of bio-diesel (5, 10, 15, 20 vol. %) was investigated. This blending technique will reduce bio-jet production cost compared to other bio-jet techniques. Bio-diesel was originally produced by the transesterification of non-edible vegetable oil (renewable sources), so, its blend with jet fuel will has a reduced carbon foot print. The blend was tested to ensure that the end product will meet the ASTM D1655 international specifications for Jet A-1 and Jet A and can be used in aircrafts.Available data on biodiesel blending with jet fuel in the literature is not consistent, there are many contradictory results. Hence, more investigations are required using locally available feedstocks. The main physicochemical properties for Jet A-1 and Jet A according to ASTM D1655 were tested to check if the blend will be compatible with existing turbojet engine systems. Different tests were conducted; vacuum distillation, smoke point, kinematic viscosity, density, flash point, total acidity and freezing point. In addition, heating value of the blend was calculated. The result was then compared with calculated value using blending indices available in the literature. Blending indices were able to predict the laboratory measured specifications for the studied blends.It was found that only 5% bio-diesel- 95% jet fuel blend (B5) meets ASTM standard for Jet A. Hence, biodiesel can be safely used as a blend with fossil-based jet for a concentration of up to 5% without any change in the ASTM specifications. Freezing point is the most important constrain for this blending technique. Higher blends of biodiesel will cause the bio-jet blend to fail ASTM specifications. In general, blending technique will reduce the cost impact that may have been incurred due to change in infrastructure when using other production techniques.

Today in Ukraine there are no reference materials of aviation fuels, including very important reference materials of specific conductivity of aviation fuels. This makes impossible to ensure the accredited laboratories activities for testing aviation fuels. The relevance of creating a set of reference materials of specific electrical conductivity of aviation fuels is caused by the need to ensure the uniformity, traceability and reliability of measurements when assessing the suitability of measurement (testing) methods and proficiency testing in testing chemmotology laboratories accredited for compliance with international standard ISO/IEC 17025. It is also caused by the intermediate inspections of measuring equipment and intra-laboratory quality control over the entire range of measurement methods realizations. An important characteristic for the safety of aircraft engines is the specific conductivity of fuels. This characteristic can be quite easily and accurately measured in each unit from the batch of reference materials. A wide range of values of specific conductivity of reference materials can be obtained with the help of specialized additives. In the article the authors analyze the existing regulations and publications on procedures for the manufacture and use of fuel reference materials in general and specific requirements for fuels used in aviation. The issue of manufacturing is considered and the results of experimental researches of homogeneity and stability of reference materials of aviation fuel taking into account the requirements of DSTU-N ISO Guide 35:2018 are given. It is proposed to create a number of aviation fuel reference materials with antistatic additive and different levels of the certified characteristic value at the range from 25 pS/m to 650 pS/m.

There is a general perception that limiting emissions of carbon dioxide will be sufficient to avoid catastrophic climate change. The reality could well be that the many of the world’s wealthy coastal cities which historically developed as ports will be inundated repeatedly to disappear eventually below the sea, with large swathes of the earth being flooded. Other major conurbations may cease to be liveable without air conditioning, while large numbers of people could well starve as a result of disruption of ecosystems. To the extent that this possibility is recognized, it is nevertheless perceived as a gradual process with the worst results in a distance future with any sea-level rise a gradual process. Limiting emissions is unlikely to be sufficient, because the level of carbon dioxide in the earth’s atmosphere is now much higher than ever before since humans started to exploit fossil fuels. We know this from the study of ancient air bubbles in Antarctic ice cores. There is a lack of balance between the energy transmitted by the incoming sunlight and the earth’s outgoing infrared heat radiation. So far this imbalance is absorbed by the enormous thermal mass of the oceans. As to the speed of sea-level rise, a period of extremely rapid sea-level rise of about 1.4 cm per year has occurred in the prehistoric past and disintegration of ice sheets as is happening currently may well be a plausible explanation of this fact. In fact, it is straightforward to create substantial amounts of negative emissions of carbon dioxide. Nevertheless, making it happen will require an unprecedented degree of global cooperation, a high level of taxation on the extraction of coal and crude oil, and the use of pressurized liquid petrol gas as aviation fuel. Graphic abstract

The spray characteristics of standard and alternative aviation fuels generated by a hybrid pressure-swirl airblast atomizer were studied at conditions corresponding to near-lean blowout conditions:...

In recent times, there has been a growing trend by airports and airlines to use aviation biofuel as an environment sustainability measure. Using an instrumental qualitative case study research design, this paper examines the evolution of sustainable aviation fuels at Oslo Airport Gardermoen. Oslo Airport Gardermoen was the first airport in the world to offer the first airport in the world to offer aviation biofuels to all airlines in 2016. The qualitative data were examined by document analysis. The study found that the use of sustainable aviation biofuels has delivered tangible environmental benefits to Oslo Gardermoen Airport. The usage of aviation biofuels has enabled the airport, and the airlines using sustainable aviation biofuels, to reduce their greenhouse gases by 10-15%. Also, as part of Norway’s efforts to reduce greenhouse gas emissions, the Norwegian Government have mandated that the aviation fuel industry must mix 0.5% advanced biofuel into jet fuel from 2020 onwards. Norway’s Ministry of Climate and Environment’s goal is that by 2030, 30% of the airline fuel will be sustainable in nature and will have a positive climate effect. Avinor, the operator of Norway’s airports, has a goal that by 2030, 30 % of aviation fuel supplied in Norway should be sustainable biofuel – this follows the Norwegian government’s mandate.

Due to the expansion of the existing Hong Kong International Airport, known as the Three Runway System, two new 500 mm diameter, 5.2 km long aviation fuel pipelines were proposed to be built throug...

Air transport is very frequent to assure worldwide social connection and commercial purposes. The use of aviation fuel demand on huge amounts becomes tensed due to the depletion of fossil fuel. Furthermore, the greenhouse emission offering vigorously by fossil fuel reduces the environment quality and human life. Therefore, it is clearly coming on priority to get attention towards alternative aviation fuel from renewable sources. However alternative fuel must be compatible with the conventional fuel in terms of its physical properties such as viscosity, energy density, sustainability, affordability and availability. The comparison to replacement of conventional fuel by alternative fuel motivates to study the properties. Measurements of Atomization spray characteristics of aviation fuels followed by comprehensive properties for a clear figure. This study is about to study the procedure to examine fuel and blends properties by developing spray atomization.

Using photochemical [2 + 2] cycloaddition, a cyclobutane dione was generated from isophorone, a condensate of bio-acetone. Hydrodeoxygenation of the dione yielded a mixture of polycyclic alkanes, whose high energy density is appropriate for high perfomance aviation applications. This work outlines a light-based approach to increase the energy density of a potential renewable carbon aviation fuel in high yields and high carbon efficiency without sacrificing performance.

Oxygen-consuming fuel tank inerting technology is a novel technology with a simple structure and a high efficiency for tank explosion suppression based on flameless catalytic combustion. To...

Biojet fuels have great potential for decreasing the reliance on fossil-based jet fuels and to decrease CO2 emissions. The International Air Transport Association reported that using sustainable sources like biomass to produce biojet fuels is a promising strategy to develop and industrialize an alternative aviation fuel to allow sustainable growth in the aviation sector. Biojet fuels chemical compositions have a significant impact on their performance characteristics. The main performance characteristics of biojet fuel are thermal oxidation stability, the biobased jet fuels compatibility with the current system of aviation, low-temperature fluidity, combustion characteristics, fuel metering, and fuel volatility. These characteristics have been evaluated by the American Society for Testing and Materials standards. The conversion technologies of biobased feedstock can be classified as alcohol to jet, sugar to jet, oil to jet, and gas to jet. Hydrogenated esters and fatty acids, hydrogenated esters, and catalytic hydrothermolysis are the common pathways for biojet fuel production. The impact of biojet fuels delivered from different feedstocks, including algae, on jet engine performance was the focus of researchers using numerical modeling and virtual simulation. Researchers found that the thermodynamic behavior, fuel consumption level of the aircraft, and emissions characteristics are improved using biojet fuel compared with the conventional jet-A fuel. The mean focus of the current chapter is to summarize the most available studies of the algae-based biojet fuels conversion technologies, characteristics, performance, and process simulation.

Sustainable Aviation Fuel (SAF) has become an important measure in the aviation industry’s efforts to mitigate carbon emissions and reduce their overall environmental impacts. However, commercial usage is relatively stunted due to a plethora of drawbacks in the production process and economic feasibility of the fuel. In this study, the currently accepted technologies for producing synthetic jet fuels under the American Society for Testing Material (ASTM D7566) standard specification for aviation turbine fuel are reviewed. The emphasis is placed in terms of their reactions, type of catalysts used for the conversion pathways of Fisher-Tropsch (FT), Hydroprocessed Esters and Fatty Acids (HEFA) and Alcohol-to-Jet (ATJ), and the use of biomass resources as feedstock. The advancement in the production process and physicochemical properties of the uncertified biojet fuels are reviewed and discussed. Generally, Co- and Fe-based catalysts are commonly used for the FT process, while bimetallic catalysts consisting of Pt, Pd, Ni and Mo have shown excellent activities and selectivities for the HEFA process. For the ATJ process, zeolites such as HZSM-5, beta and SAPO have shown remarkable ethanol dehydration efficiency, while TiO2 and ferrierite have been studied for the combined iso-butanol dehydration and oligomerisation processes. Fundamental factors influencing the reaction efficiency including the feedstock properties, reaction conditions, catalytic reusability and catalyst supports are discussed. Finally, the key challenges and prospects for biojet fuel commercialisation are addressed.

With rising concerns over commercial aviation's contribution to global carbon emissions, the aviation industry faces tremendous pressure to adopt advanced solutions for reducing its share of CO2 emissions. One near-term potential solution to mitigate this global emissions situation is to operate existing aircraft with sustainable aviation fuel (SAF); this solution requires almost no modification to current aircraft, making it the "quickest'' approach to reduce aviation carbon emissions, albeit the actual impact will be determined by the degree to which airlines adopt and use SAF, the ticket price impact of SAF, and the future growth of travel demand. This article presents research results that estimate the expected fleet-wide emissions of future airline operations using SAF considering various projected traveler demand and biofuel penetration/utilization levels. The work demonstrates an approach to make these predictions by modeling the behavior of a profit-seeking airline using the Fleet-Level Environmental Evaluation Tool (FLEET). FLEET's model-based predictions rely upon historically-based information about US-touching airline routes and passenger demand served by US flag-carrier airlines available from the Bureau of Transportation Statistics to provide the basis for predictions of future travel demand, aircraft fleet mix, and aircraft operations. Considering five future SAF scenarios and two future passenger demand projection scenarios, this work estimates the future fleet-level CO2 emissions, along with predicting the demand served and trips flown. Results show that the future fleet-level CO2 emissions for all scenarios with SAF are lower than the baseline scenario with no SAF, for all demand projection scenarios. The passenger demand served and the trips flown for a given SAF scenario depends on the SAF price and the biofuel penetration levels. This shows that even if airlines serve a higher passenger demand for some future scenarios, the carbon emissions could still be lower than the current baseline scenario where airlines only use conventional jet fuel.

The United States, spurred in part by international developments, is expanding its law and policy to incentivize the use of sustainable aviation fuels. While the U.S. has agreed to participate in the International Civil Aviation Organization’s (ICAO’s) Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), it has only recently adopted federal rules that define greenhouse gas emission reduction standards for certain classes of airplanes (effective January 2021). However, such standards focus on engine efficiency rather than the fuel burned. For sustainable aviation fuels, the U.S. continues to rely on voluntary programs at a federal, state, and regional level. The federal Renewable Fuel Standard program allows producers to opt in. In addition, states have started to allow sustainable aviation fuel producers to “opt in” to their programs; this includes California’s Low Carbon Fuel Standard, Oregon’s Clean Fuels Program, and Washington’s newly adopted Clean Fuels Program. Other states are also starting to consider such programs. Elsewhere, states like Hawaii are starting to support SAF production in other ways, including through tax mechanisms. In addition, regional and private efforts to adopt and/or promote sustainable aviation fuels are underway. This piecemeal approach—due in part to the lack of cohesive U.S. federal policy—stands in contrast to the European Union’s Renewable Energy Directive and Emissions Trading System, and adoption of policies by European countries. Because of aviation’s international nature, tracking what is happening in Europe matters greatly for U.S. carriers. As the U.S. works to meet its international obligations through CORSIA, finding a way forward with sustainable aviation fuel in the United States may depend on a more defined federal policy. Actions taken by both the EU and European countries offers some guidance for actions that could be taken by the U.S. Even in the absence of more defined measures, better tracking of voluntary measures is a critical step.

The contamination and behaviour of water in aircraft fuel systems remains a significant global research interest following several aircraft incidents. To engineer a solution to the problem of icing in jet fuel, it is crucial to precisely identify the conditions and features that may exacerbate this phenomenon. This review will aid prospective researchers to identify work that has been done and work that is yet to be available for future study. In this review, conclusive data integrating a wide range of literature and also providing an in-depth description of the factors that influence the behaviour of trace water, ice formation in jet fuels was carefully summarised. On investigational studies, it was discovered that to date, no work is available that studies the impact of sustainable jet fuel and its blends on ice formation, size and frequency distribution of dispersed water droplets in aircraft fuel systems. Findings from comparative studies also reveal that surfaces will have an essential role in the growth pattern of ice in aircraft fuel systems. Furthermore, findings show that supercooled water droplets with sizes greater than or equal to 5 µm can induce ice accretion. This review identified a common problem with the prominent methods of reporting results as a graphically fitted plot. Subsequently, it proposed that authors of any original technical work provide raw data as supplementary information to allow comprehensibility. The study further offers a system that could help manage the nature of ice in aircraft fuel tank systems—making it readily available and accessible.

Nonvolatile particulate matter (nvPM) emissions from aircraft turbine engines deteriorate air quality and contribute to climate change. These emissions can be reduced using sustainable aviation fuels (SAFs). Here, we investigate the effects of a 32% SAF blend with fossil fuel on particle size distributions and nvPM emission indices of a widely used turbofan engine. The experiments were conducted in a test cell using a standardized sampling and measurement system. The geometric mean diameter (GMD) increased with thrust from ∼8 nm at idle to ∼40 nm at take-off, and the geometric standard deviation (GSD) was in the range of 1.74-2.01. The SAF blend reduced the GMD and GSD at each test point. The nvPM emission indices were reduced most markedly at idle by 70% in terms of nvPM mass and 60% in terms of nvPM number. The relative reduction of nvPM emissions decreased with the increasing thrust. The SAF blend reduced the nvPM emissions from the standardized landing and take-off cycle by 20% in terms of nvPM mass and 25% in terms of nvPM number. This work will help develop standardized models of fuel composition effects on nvPM emissions and evaluate the impacts of SAF on air quality and climate.

Designing commercial aircraft to use liquid hydrogen (LH2) is one way to substantially reduce their life-cycle CO2 emissions. The merits of hydrogen as an aviation fuel have long been recognized, however, the handling of a cryogenic fuel adds complexity to aircraft and engine systems, operations, maintenance and storage. The fuel tanks could account for 8–10% of an aircraft’s operating empty weight, so designing them for the least added weight is of high significance. This paper describes the heat transfer model developed in the EU Horizon 2020 project that is used to predict heat ingress to a cylindrical tank with hemispherical end caps with external foam insulation. It accounts for heat transfer according to the state of the tank contents, the insulation material properties, the environment, and the dimensions of the tank. The model also estimates the rate of pressure change according to the state of the fuel and the rate at which fuel is withdrawn from the tank. In addition, a methodology is presented, that allows for tank sizing taking into consideration the requirements of a design flight mission, the maximum pressure developed, and the fuel evaporated. Finally, the study demonstrates how to select optimal insulation material and thickness to provide the lightest design for the cases where no gaseous hydrogen is extracted, and where some hydrogen gas is extracted during cruise, the latter giving gravimetric efficiencies as high as 74%.

Thin-layer cascades (TLCs) enable algae cultivation at high cell densities, thus increasing biomass yields and facilitating the harvest process. This makes them a promising technology for industrial-scale algal fuel production. Using Life Cycle Assessment (LCA), we calculate the greenhouse gas (GHG) emissions of aviation fuel produced using algal biomass from TLCs. We find that the impact (81 g CO2e per MJ) is lower than that of fuel from algal biomass cultivated in open race way ponds (94 g CO2e). However, neither of the two cultivation systems achieve sufficient GHG savings for compliance with the Renewable Energy Directive II. Seawater desalination in particular dominates the TLC impact, indicating a trade-off between carbon and water footprint. In both cultivation systems, the mixing power and fertilizer consumption present further significant impacts. There is uncertainty in the correlation between mixing power and algal oil yield, which should be investigated by future experimental studies.

A method for identifying straits of rocket kerosene (RG-1 and T-1 brands) and various types of hydrocarbon fuels (aviation fuel TC-1 and diesel fuel) in soil has been developed. The proposed version of identification is based on the preliminary separation of the main components by gas chromatography and their mass spectrometric detection followed by the processing of the data obtained by chemometric methods of analysis (principal component analysis and projection on latent structures with discriminant analysis) using the “MZmineZ,” “iMet-Q,” and “MetaboAnalyst” software. A possibility of the application of the developed approach to the typification of saturated oil fractions of different origin is illustrated.

An underpinning hindrance in the market penetration of sustainable aviation fuel is the approval process for alternative jet fuels. One solution to this is to develop low-cost screening tools that ...

To reduce aviation carbon emissions, the International Civil Aviation Organization initiated the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), which will take effect in 2021. In response, airlines have taken measures through various means, including the use of sustainable fuels. This article investigates the potential effects of a CORSIA-type policy when implemented in the United States. The study uses a combined model of airlines operations and multi-feedstock sustainable aviation fuels (SAFs) to represent decisions of several actors, such as farmers, bio-refineries, airlines, and policymakers. The research employed a life-cycle assessment and Monte-Carlo simulation to evaluate two policy scenarios on the amount of SAF consumption and the resulting emissions. Implementing a CORSIA-type policy could stimulate the demand and production of SAFs, while also reducing air travel growth by increasing airfare. As a result of this combined effect and improved aircraft technology, there is a 3.5% chance that the U.S. airlines industry can reduce greenhouse gas (GHG) emissions by 37.5–50% by the year 2050, compared to the 2005 emission levels. Despite a projected increase in air travel in 2050 by a factor of 2.75 (the median value), the emissions in 2050 are expected to rise to only 120% (the median value) of the 2005 level. The price of petroleum-based aviation fuels followed by the growth rate of the carbon price are the two most important factors to determine whether the CORSIA-type policy would achieve the emission reduction target.

Modern trends of civil aviation development indicate the need to improve fuel efficiency and environmental friendliness of the utilized fuels. The use of conventional jet fuel is meeting to a lesser degree the promising requirements concerning environmental friendliness at a constantly rising price for it. Apart from that, oil reserves are limited. According to many experts, the solution to the growing problems with oil fuels can be application of alternative types of aviation fuel. A number of companies around the world, together with aircraft manufacturers under the significant state support, are actively developing new types of fuel. At the moment the most widespread biofuels consisting of bioethanol are obtained from various plant and animal sources. Alternative fuels should not be inferior to petroleum fuels in its operational properties. A possible transition to them should not require significant costs for the modernization of aircraft and facilities of ground aviation fuel supply. Therefore, an urgent task is to compare the main indicators of the quality of oil fuels, biofuels and their mixtures to assess the possibility of using biofuels on aircraft. A comparative analysis was carried out on some quality indicators. Afterwards the comments were given on the impact of changes of these quality indicators on the performance properties of the fuels. It is shown that according to some quality indicators, biofuels under research have the advantages over oil ones. The relevance of comprehensive study of the performance properties of biofuels is obvious. The improvement of oil fuels and their comprehensive study have been under way for more than 60 years. Biofuels are just beginning their life, so it is reasonable to conduct thorough research on their use in aviation.

The worldwide utilization of fossil energy, including its specific application as transportation fuel, significantly contributes to the continuous increase of the atmospheric CO2 concentration. Several solutions have been promoted or scheduled to reduce CO2 emissions. Among these solutions, the development of renewable energy resources, such as bio-fuels, offers important advantages as promoted by several countries and institutions who disclosed their plans to partly or totally use alternative renewable energy sources in the future. For the rapidly growing aviation sector, aviation fuel derived from fossil resources is still the major available energy source. The development of renewable aviation fuel is considered to be a promising future strategy to reduce related CO2 emissions. The worldwide total aviation fuel consumption by commercial airlines increased from about 260 million m³/year in 2005 to over 340 million m³/year in 2018, and a further annual increase of about 5% is expected till 2050. Worldwide actions have hence been undertaken with respect to bio-aviation fuel production, distribution, and demonstration flying. As a relatively new topic, there are a lot of remaining challenges in technology development, fuel certification and distribution. The production technology, policy and environmental impact of bio-aviation fuel were comprehensively reviewed, including its production by the catalytic conversion of lipids, by the conversion of carbohydrates or lignocellulosic biomass, and by developing bio-refinery concepts for bio-aviation fuel production. The future reduction of CO2 emissions in the aviation sector requires an improvement of the biomass to aviation fuel production technology through the correct integration of biology, chemical engineering, and energy crops. The paper illustrates this potential integration through reviewing the current research in the production of aviation fuels from biomass, including the complete industrial chain from airplane manufacturer, aviation fuel producer and provider, airline strategies, and ongoing R&D, bearing in mind that major efforts are required to foster the development of the cost-effective production of renewable aviation fuel. The different topics of the Table of contents will be subsequently dealt with.

It is anticipated that the next twenty years the air transport will present an increase of almost double the growth rate of world GDP. This accelerated expansion of the sector has caused some negative consequences, such as the significant increase in carbon dioxide emissions. The aviation industry has already committed in changing this scenario and the target is to halve CO2 emissions by 2050. To achieve this goal, it is necessary to planning eco-efficient aviation fuel, which allows the reduction by 80% of CO2 emissions. The identification of alternatives to this replacement has been carried out in different research groups; however, it is clear that the planning of innovation has been carried out not integrated manner. In this sense, this study seeks to fill this theoretical gap and to contribute to this issue proposing a management tool to guide innovation in this sector. From Delphi method, it was found that the proposed scheduling method, identified as IPMEF-AT, would be considered applicable to the context in which it is intended, the innovation planning of ecoefficient air transportation fuels. The result obtained demonstrates the viability of IPMEF-AT and suggestions of experts were used in order to improve it. Keywords: Air transport. Eco-efficient fuel. Management of innovation.

This study considered the techno-economic evaluations for the economic feasibility of jatropha derived hydro-processed renewable jet (HRJ) fuel, starting from the farming processes to the refinery (fruit-to-fuel) processes, based on the situations in Taiwan. The farming processes included plantation, growing and harvesting. The fruit-to-fuel processes included fruit dehulling, shell combustion, oil extraction, pyrolysis of press cake, oil refinery and product separation. In addition, the calculated minimum jet fuel selling price (MJSP) was compared to the cases from two different countries (Thailand and Cambodia) and to the scenario without cultivation. The MJSP of the Taiwan case, $6.25/L jet fuel, was higher than the cases of Thailand and Cambodia as well as the without-cultivation scenario. Moreover, according to the annual aviation fuel consumption from one of the aviation companies in Taiwan, the MJSPs of various blending fractions were calculated and compared with the cases of Thailand and Cambodia.

The feedstock has been the most significant issue for promoting a sustainable and economical renewable aviation fuel in Taiwan. In this study, the potential feedstocks available for producing hydro-processed renewable jet (HRJ) fuel locally in Taiwan were evaluated economically through the process simulation and techno-economic analysis. The productivities, H2 consumptions, product distributions and properties of the produced fuel, which strongly depend on the fatty acid content within the oil/fat feedstocks, were demonstrated and discussed. The baseline economics, sensitivity analyses and pioneer plant analyses were also conducted in accordance with the simulation results. The minimum aviation fuel selling prices (MAFPs) of all feedstocks were calculated ranging from $0.91/L∼ $2.74/L. The feedstock costs, prices of hydrogen, prices of hydro-processing catalyst and plant capacities have influences on the selling prices of renewable aviation fuel by 54%, 18%, 12% and 11%, respectively. Furthermore, although the greases have the most economical benefits among the selected feedstocks, the feedstock pretreatment processes lead to the complexity of the production and result in higher pioneer plant costs compared to the ones of plant oils. This study provides the suggestions for the government to locally select an appropriate HRJ feedstock.

Current trends of civil aviation development show a significant increase in the number of aircraft with aircraft piston engines. The Ministry of Transport of the Russian Federation is preparing a draft order on amendments to the Federal aviation rules for the preparation and performance of flights in civil aviation (FAP-128), which stipulate for simplified procedures of paid excursion flights implementation for light and ultralight aircraft and helicopters. It is obvious that this circumstance will significantly affect the expansion of the fleet of these aircraft. Accordingly, the state of piston engines operating on aviation gasoline value questions are becoming increasingly relevant. The current problems of aviation engines diagnostics by metal contents in oils are observed in the article. Their bugs, possible ways of solving this problems and bugs, actual developments in this direction are shown. The application examples of early diagnostic methods using the automated diagnostic complex “Prisma” are shown. The oil samples taken from An-2 aircraft АШ-62ИР piston engine analyses results attract the most interest. They show that with proper training of personnel the valuable information coming from the oil samples can be a source of important conclusions not only in aircraft engines accessories and assemblies state value, but also others systems, and also conclusions about the quality of fuel and lubricants used. Estimating the residual life method of the engine at various stages of its operating time on the metal content in the oils and the procedure for oil selecting, allowing to obtain reliable results, are suggested.

Renewable aviation fuel produced from hydro-processing has been a commercially available technique currently. Studies conducted recently were toward finding an appropriate catalysts to produce the jet fuel range products with high normal alkanes and low aromatics. This study focused on hydro-processing of waste cooking oil (WCO) into straight alkanes, which can serve as the blendstock for aviation fuel after further cracking and isomerizing, over two different catalysts, pre-sulfurized NiMo/γ-Al2O3 and Pd/C, under various experimental conditions such as reaction temperature, pressure, liquid hourly space velocity (LHSV) and H2-to-oil ratio. The resulting liquid and gas products from the two catalysts were analyzed through GC-MS/FID and GC-TCD for judging the performances of hydro-deoxygenation (HDO) as well as decarboxylation (DCO2)/decarbonylation (DCO). The fresh and spent catalysts were examined through XRD, FTIR, TGA and SEM to characterize the catalysts before and after hydro-processing. The performance of Pd/C, based on the concentrations of produced C15∼C18 normal alkanes, was higher than NiMo/γ-Al2O3 with low reaction temperature, low hydrogen pressure, low LHSV, low H2-to-oil ratio and short time-on-stream.

Summary The catalytic conversion of renewable lignocellulose to transportation fuels is crucial to establish energy security and mitigate CO2 emissions. Here, we describe an effective and integrated strategy for the production of high-density aviation fuel with cellulose, an abundant and inedible raw biomass. First, cellulose was selectively converted to 2,5-hexanedione in a separation yield of 71.4%. Subsequently, a mixture of C12 and C18 branched polycycloalkanes was directly obtained in a carbon yield of 74.6% by the aldol condensation-hydrogenation and hydrodeoxygenation reaction of 2,5-hexanedione and hydrogen over a dual-bed catalyst system. The polycycloalkane mixture obtained by this process has high density (0.88 g mL−1) and low freezing point (225 K). In real application, they can be used as advanced aviation fuel or additives to improve the volumetric heat values of conventional aviation fuels.

Stakeholders in the aviation industry committed to a goal of 50% reduction in carbon emissions by the year 2050, to be achieved by reducing emissions 1.5% each year from 2020 onwards. There are multiple pathways to achieve this goal however; with, the most promising technology being Sustainable Aviation Fuels (SAF), which are biofuels blended with kerosene. As the industry shifts towards SAF, it is important to evaluate these fuels in terms of their long-term sustainability, and this is the objective of the current study. Sixteen types of fuels were assessed which include fossil, natural gas, electric, and SAF. A Multi Criterion Decision Making methodology was adopted which considers three categories, namely environmental, economic, and social aspects which in turn are broken up into 8 indicators in all (such as ecological footprints, cost of transportation, investment cost, operating costs, employment generation, and health & safety). A Monte Carlo analysis was also performed to analyze sensitivity of the results to the weights attributed to the three categories. The most sustainable fuel was found to be Hydrogen, with a score of 0.91 out of 1.0. The least sustainable were determined to be the military kerosene-based fuels (with the experimental fuel JP-8 + 100LT being the poorest with a normalized score of 0.50).

The negative environmental impact of the aviation industry, related mainly to the gaseous emissions from turbine exhausts, is increasing with the increased demand on travel. In addition to the adverse environmental effects, the currently used aviation fuel is posing economic burdens on the air transport sector, with the increase in crude oil prices. Therefore, the aviation industry is investigating the potential of substituting the currently used aviation fuel with alternative fuels- mainly with those derived from second generation biofuels. Of all available sources of second generation biofuels, numerous studies indicate that those derived from algae seem to be the most promising, in terms of providing a viable and sustainable alternative to fossil fuels. This study explores the feasibility of microalgal jet fuel, taking into consideration technological, environmental and economic aspects. The results indicate that the viability and sustainability of microalgal jet fuel greatly depend on the technologies and inputs used during the different production stages of microalgal fuels. Provided certain conditions and characteristics are present, microalgal jet fuel has a realistic potential to provide the economic and environmental benefits needed to substitute conventional fuels.