Academic literature on the topic 'Alternative aviation biofuels'
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Journal articles on the topic "Alternative aviation biofuels"
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Marsh, George. "Biofuels: aviation alternative?" Renewable Energy Focus 9, no. 4 (July 2008): 48–51. http://dx.doi.org/10.1016/s1471-0846(08)70138-0.
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Khan, M. Anwar H., Sophia Bonifacio, Joanna Clowes, Amy Foulds, Rayne Holland, James C. Matthews, Carl J. Percival, and Dudley E. Shallcross. "Investigation of Biofuel as a Potential Renewable Energy Source." Atmosphere 12, no. 10 (October 3, 2021): 1289. http://dx.doi.org/10.3390/atmos12101289.
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An accelerating global energy demand, paired with the harmful environmental effects of fossil fuels, has triggered the search for alternative, renewable energy sources. Biofuels are arguably a potential renewable energy source in the transportation industry as they can be used within current infrastructures and require less technological advances than other renewable alternatives, such as electric vehicles and nuclear power. The literature suggests biofuels can negatively impact food security and production; however, this is dependent on the type of feedstock used in biofuel production. Advanced biofuels, derived from inedible biomass, are heavily favoured but require further research and development to reach their full commercial potential. Replacing fossil fuels by biofuels can substantially reduce particulate matter (PM), carbon monoxide (CO) emissions, but simultaneously increase emissions of nitrogen oxides (NOx), acetaldehyde (CH3CHO) and peroxyacetyl nitrate (PAN), resulting in debates concerning the way biofuels should be implemented. The potential biofuel blends (FT-SPK, HEFA-SPK, ATJ-SPK and HFS-SIP) and their use as an alternative to kerosene-type fuels in the aviation industry have also been assessed. Although these fuels are currently more costly than conventional aviation fuels, possible reduction in production costs has been reported as a potential solution. A preliminary study shows that i-butanol emissions (1.8 Tg/year) as a biofuel can increase ozone levels by up to 6% in the upper troposphere, highlighting a potential climate impact. However, a larger number of studies will be needed to assess the practicalities and associated cost of using the biofuel in existing vehicles, particularly in terms of identifying any modifications to existing engine infrastructure, the impact of biofuel emissions, and their chemistry on the climate and human health, to fully determine their suitability as a potential renewable energy source.
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Azam, Qummare, Ahmed Mahjub Alhaj, Mohd Shukur Zainol Abidin, Siti Zubaidah Sulaiman, and Nurul Musfirah Mazlan. "AN OUTLINE OF ALTERNATIVE AVIATION FUELS FROM SUSTAINABLE RESOURCES." Jurnal Teknologi 85, no. 1 (December 2, 2022): 11–19. http://dx.doi.org/10.11113/jurnalteknologi.v85.14563.
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The depletion of fossil fuels and their market inequality have led to the popularity of biofuels. Biofuels are a renewable energy source which can be a promising solution to the environmental issues created by fossil fuels. The emission of greenhouse gases and fluctuating prices of fossil fuels have put pressure on developing countries and small economic nations. Thus, one of the main concerns is the production of bio jet fuel from renewable resources, with a relatively low greenhouse gas life cycle and sustainability with affordable prices. Therefore, it is imperative to introduce and produce alternative aviation fuels generated from sustainable resources, specifically biofuels. In this study, we have reviewed alternative aviation fuels and their sources. We have also outlined the selection criteria for alternative aviation fuels along with discussing the sources that can be potentially used as fuel for the aviation industry.
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Aldarrai, Houreya, Dhabya Alsuwaidi, Beenish Khan, Haoyang Xu, and Elham Tolouei. "Numerical Investigation of Bio-Aviation Fuel: Dubai’s Future Perspective." Aerospace 10, no. 4 (March 28, 2023): 338. http://dx.doi.org/10.3390/aerospace10040338.
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As part of the United Arab Emirates’ and the world’s aviation goal of reaching net-zero greenhouse gas emissions by 2050, this paper studied the potential of successfully implementing both biofuel “drop-in” alternatives and aerodynamically efficient configurations to decarbonize the aviation industry. By investigating various proposed designs through a PUGH analysis, it was concluded that the optimum design has a Transonic Truss-Braced Wing configuration and runs on 60% biofuel. Although the design stipulates a 1.3% increase in weight, this does not negate the reduction in emissions and fuel consumption. This study also explored the various types of biofuels and found camelina seeds to be the best choice. The effects of biofuels in comparison with Jet-A fuel were further deliberated in a fuel combustion simulation performed on the Ansys-Fluent software. The results of the simulation showed a reduction of 50% in carbon monoxide (CO) and 24% in carbon dioxide (CO2) emissions when burning camelina biofuel rather than Jet-A, making it an ideal alternative to those conventional jet fuels. A primary cost analysis of biofuel applications showed an increase of 453 USD (1653.18 AED) per passenger flying on board 100%-biofuel-powered aircrafts. Yet, considering the trend of the cost increase with the biofuel blend ratio, a solution may exist to the increased cost of biofuel-powered aircrafts.
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Varakin, A. N., L. A. Gulyaeva, D. I. Ishutenko, A. L. Kulinich, P. A. Nikulshin, A. A. Pimerzin, and R. G. Vasilov. "Development of Technologies and Prospects for the Introduction of Aviation Biofuels." Biotekhnologiya 36, no. 5 (2020): 13–30. http://dx.doi.org/10.21519/0234-2758-2020-36-5-13-30.
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An overview of the current state of production technologies of biojet fuels in the world and in Russia is presented. The contribution of the aviation sector to climate change processes and the likelihood of achieving global environmental goals in the event of large-scale production of alternative aviation fuels are assessed. The level of commercialization, constraining factors and possible measures to support synthetic kerosene production technologies are reviewed. Special attention is paid to the current international certification procedure for aviation biofuels. aviation biofuel, biojet fuels, synthetic kerosene, global warming, climate change, greenhouse gases emission, sustainable biofuel, ASTM certification, biomass conversion, photosynthetic microorganisms, microalgae. The review was financially supported by the Ministry of Science and Higher Education of the Russian Federation, project no. 14.574.21.0139 (Unique Project Identifier RFMEFI57417X0139).
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Stanton, Brian J., and Richard R. Gustafson. "Advanced Hardwood Biofuels Northwest: Commercialization Challenges for the Renewable Aviation Fuel Industry." Applied Sciences 9, no. 21 (November 1, 2019): 4644. http://dx.doi.org/10.3390/app9214644.
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A bioenergy summit was organized by Advanced Hardwood Biofuels Northwest (AHB) to debate the barriers to the commercialization of a hybrid poplar biofuels industry for the alternative jet fuels market from the perspective of five years of AHB research and development and two recent surveys of the North American cellulosic biofuels industry. The summit showed that: (1) Growing and converting poplar feedstock to aviation fuels is technically sound, (2) an adequate land base encompassing 6.03 and 12.86 million respective hectares of croplands and rangelands is potentially available for poplar feedstock production, (3) biofuel production is accompanied by a global warming potential that meets the threshold 60% reduction mandated for advanced renewable fuels but (4) the main obstruction to achieving a workable poplar aviation fuels market is making the price competitive with conventional jet fuels. Returns on investment into biomass farms and biorefineries are therefore insufficient to attract private-sector capital the fact notwithstanding that the demand for a reliable and sustainable supply of environmentally well-graded biofuels for civilian and military aviation is clear. Eleven key findings and recommendations are presented as a guide to a strategic plan for a renewed pathway to poplar alternative jet fuels production based upon co-products, refinery co-location with existing industries, monetization of ecosystem services, public-private financing, and researching more efficient and lower-costs conversion methods such as consolidated bioprocessing.
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Adami, Renata, Patrizia Lamberti, Vincenzo Tucci, Liberata Guadagno, Arnaldo Rosa Valdés, Oleksandr Zaporozhets, Pawel Wacnik, and Serhat Burmaoglu. "Alternative fuels for aviation: possible alternatives and practical prospects of biofuels." IOP Conference Series: Materials Science and Engineering 1024, no. 1 (January 1, 2021): 012113. http://dx.doi.org/10.1088/1757-899x/1024/1/012113.
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Boichenko, S. V., A. V. Yakovlieva, O. V. Gryshchenko, and A. M. Zinchuk. "PROSPECTS OF USING DIFFERENT GENERATIONS BIOFUELS FOR MINIMIZING IMPACT OF MODERN AVIATION ON ENVIRONMENT." Energy Technologies & Resource Saving, no. 1 (April 24, 2018): 10–20. http://dx.doi.org/10.33070/etars.1.2018.02.
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The work is devoted to the overview of prospects of development and implementation of alternative motor fuels from various types of biomass. The article outlines problems of modern transport that is connected to limitation of conventional energy resources used for fuels production. Main environmental problems connected with the use of conventional aviation fuels are determined. Modern trends for transition from conventional aviation fuels to alternative ones are presented. The article gives versatile analysis of well-developed types of biomass for biofuels production and also perspective types, which may be sufficiently used in the near future. The main properties of oil plants used for biofuels production are described, as well as advantages of biofuels use from considered types of biomass. Bibl. 26, Fig. 1, Tab. 4.
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Gryadunov, K. I., A. N. Kozlov, V. M. Samoylenko, and Shadi Ardeshiri. "Comparative analysis of quality indicators of aviation kerosine, biofuels and their mixtures." Civil Aviation High Technologies 22, no. 5 (October 28, 2019): 67–75. http://dx.doi.org/10.26467/2079-0619-2019-22-5-67-75.
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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.
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Azami, Muhammad Hanafi, and Mark Savill. "Comparative study of alternative biofuels on aircraft engine performance." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 8 (June 22, 2016): 1509–21. http://dx.doi.org/10.1177/0954410016654506.
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Aviation industries are vulnerable to the energy crisis and simultaneously posed environmental concerns. Proposed engine technology advancements could reduce the environmental impact and energy consumption. Substituting the source of jet fuel from fossil-based fuel to biomass-based fuel will help reduce emissions and minimize the energy crisis. The present paper addresses the analysis of aircraft engine performance in terms of thrust, fuel flow and specific fuel consumption at different mixing ratio percentages (20%, 40%, 50%, 60% and 80%) of alternative biofuel blends already used in flight test (Algae biofuel, Camelina biofuel and Jatropha biofuel) at different flight conditions. In-house computer software codes, PYTHIA and TURBOMATCH, were used for the analysis and modeling of a three-shaft high-bypass-ratio engine which is similar to RB211-524. The engine model was verified and validated with open literature found in the test program of bio-synthetic paraffinic kerosene in commercial aircraft. The results indicated that lower heating value had a significant influence on thrust, fuel flow and specific fuel consumption at every flight condition and at all mixing ratio percentages. Wide lower heating value differences between two fuels give a large variation on the engine performances. Blended Kerosene–Jatropha biofuel and Kerosene–Camelina biofuel showed an improvement on gross thrust, net thrust, reduction of fuel flow and specific fuel consumption at every mixing ratio percentage and at different flight conditions. Moreover, the pure alternative of Jatropha biofuel and Camelina biofuel gave much better engine performances. This was not the case for the Kerosene–Algae blended biofuel. This study is a crucial step in understanding the influence of different blended alternative biofuels on the performance of aircraft engines.
Dissertations / Theses on the topic "Alternative aviation biofuels"
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Zoccatelli, Michele, and Edoardo Nascimbeni. "Transformation of the Aviation industry : Exploring alternative renewal fuel pathways." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-301640.
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This master thesis will be part of a larger project called Sustainable Energy Transition in Aviation (SETA), which will be done in collaboration with the Division of Sustainability, Industrial Dynamics and Entrepreneurship (SIDE) at INDEK. The overall thesis aims to contribute to accelerate the energy transition within the aviation sector, with a focus on three technologies: bio-based jet fuels, hydrogen fuels and electrical aircraft. Moving on, this research project is being pursued because aviation is one of the most important CO2 emitters in Sweden. Indeed it accounts for 5% of total Swedish emissions (Klimatpolitiska Rådet, 2020). Due to its complexity as a socio technical system and its tight interrelations between its components, aviation is struggling to change. Therefore, a transformative pressure is raising in order to meet 2030 and 2045 targets. The aim of the research is to highlight how the introduction of alternative fuels and technologies might help aviation to reach carbon neutrality. Moreover, the aviation industry could be classified as a socio-technical system, thereby a conceptual framework was used to better analyze its transition. The Multi-Level Perspective framework (MLP) was thus applied with the intent of describing how the sustainable energy transformation will happen at the different levels. Through interviews it was possible to underline the different challenges within the aviation system, while also highlighting future scenarios of the air transport sector. Furthermore, by developing a modelling analysis through the LEAP software, it was possible to hypothesized several scenarios where biofuels, hydrogen and electric airplanes growth varies under specific assumptions. Finally, the analysis highlighted that the introduction of these alternative technologies will be crucial to support aviation in its green transformation. Indeed, between year 2015 and 2045, the total emissions from the analyzed transport sector were reduced by 90%. Therefore, aviation will essentially need these new technologies in order to transform and become greener.Detta examensarbete kommer att ingå i ett större projekt som heter Sustainable Energy Transition in Aviation (SETA), vilket kommer att göras i samarbete med avdelningen för hållbarhet, industriell dynamik och entreprenörskap (SIDE) vid INDEK. Den övergripande avhandlingen syftar till att bidra till att påskynda energiövergången inom flygsektorn, med fokus på tre tekniker: biobaserade jetbränslen, vätgasbränslen och elektriska flygplan. Detta forskningsprojekt pågår eftersom luftfarten skapar stora mängder koldioxidutsläpp i Sverige. Det står för 5% av de totala svenska utsläppen (Klimatpolitiska Rådet, 2020). På grund av dess komplexitet som ett sociotekniskt system och dess snäva samband mellan komponenter, kämpar luftfarten för att förändras. Därför ökar ett transformerande tryck för att nå 2030 och 2045 mål. Syftet med forskningen är att belysa hur införandet av alternativa bränslen och tekniker kan hjälpa luftfarten att nå koldioxidneutralitet. Dessutom kan flygindustrin klassificeras som ett socio-tekniskt system, varigenom en konceptuell ram användes för att bättre analysera dess övergång. Multi-Level Perspective Framework (MLP) tillämpades således med avsikten att beskriva hur den hållbara energiomvandlingen kommer att ske på de olika nivåerna. Genom intervjuer var det möjligt att ta fram de olika utmaningarna inom flygsystemet, samtidigt som man framhävde framtida scenarier inom lufttransportsektorn. Genom att utveckla en modelleringsanalys genom LEAPprogramvaran var det dessutom möjligt att hypotisera flera scenarier där biodrivmedel, väte och elektriska flygplanstillväxt varierar under specifika antaganden. Slutligen visade analysen att införandet av dessa alternativa tekniker kommer att vara avgörande för att stödja luftfarten i dess gröna omvandling. Mellan 2015 och 2045 minskade de totala utsläppen från den analyserade transportsektorn med 90%. Därför kommer luftfarten i huvudsak att behöva dessa nya tekniker för att förändras och bli grönare.
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Aftab, Mohammad Adnan. "Biofuel, An alternative source for jet fuel in Aviation." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-34914.
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The transport industry is one of the fastest growing industries with the sector playing a significant role in negative impact on global warming and pollution through the emission of greenhouse gases. Aviation in particular, has enjoyed growth especially in the few decades. New airlines and aircraft manufacturers are coming up with different innovations and technologies to ensure they make the best possible environmentally friendly aircraft. The new main area of focus has been on how to come up with fuel that will reduce the greenhouse gas-emissions. The stakeholders in the same effort include developed nations like the United States, United Kingdom, Russia, France, Germany, and Canada among others. Energy providers as well as jet fuel suppliers are also making efforts to conserve the environment. The purpose of this thesis is to explore the area of biofuel in aviation by looking into various stakeholders involved in the efforts of the transition from fossil fuel to biofuel. The conclusion of this thesis is that biofuels are viable options in the aviation industries since there have been positive results in the tests made.
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Vankeswaram, Sai Krishna. "Atomization Characteristics of Camelina and Jatropha-Derived Drop-in Aviation Biofuels." Thesis, 2015. http://etd.iisc.ac.in/handle/2005/2784.
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Biofuels in civil aviation is actively studied in recent years to identify potential alternative jet fuels to meet stringent environmental regulations imposed to tackle degraded air quality caused by fossil fuel combustion. In this context, the aviation industry prefers to develop ‘drop-in’ fuels which may not require substantial modifications in existing jet engine technologies. The thesis aims at evaluating the atomization characteristics of camelina- and jatropha-derived drop-in biofuels discharging from simplex swirl atomizer used in aircraft gas turbine engines. The test fuels are characterized in detail and all fuels meet current ASTM D7566 specifications. The experiments are conducted by discharging fuel spray into quiescent atmospheric air in a fuel spray booth to obtain spray characteristics such as fuel discharge behaviour, spray cone angle, breakup behaviour of swirling fuel sheet and spray drop size distribution. The characteristics of sheet breakup are deduced from the captured images of biofuel sprays and the measurements of spray droplet size distribution are obtained using Spraytec (laser-diffraction instrument). A systematic comparison is made between the biofuel sprays and the 100% Jet A-1 (conventional aviation kerosene) sprays to evaluate the drop-in feature of the biofuels. All the measured spray characteristics of the biofuel sprays follow the Jet A-1 both in qualitative and quantitative terms which ensure the drop-in nature of the tested biofuels. The minor differences observed in the comparison of the quantitative spray measurements are attributed to the variation in the fuel properties. This claim is supported using the predictions obtained from the liquid film breakup model and the empirical correlation reported in the literature for the determination of sheet breakup characteristics and mean drop size for sprays discharging from simplex swirl atomizers.
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Vankeswaram, Sai Krishna. "Atomization Characteristics of Camelina and Jatropha-Derived Drop-in Aviation Biofuels." Thesis, 2015. http://etd.iisc.ernet.in/handle/2005/2784.
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Biofuels in civil aviation is actively studied in recent years to identify potential alternative jet fuels to meet stringent environmental regulations imposed to tackle degraded air quality caused by fossil fuel combustion. In this context, the aviation industry prefers to develop ‘drop-in’ fuels which may not require substantial modifications in existing jet engine technologies. The thesis aims at evaluating the atomization characteristics of camelina- and jatropha-derived drop-in biofuels discharging from simplex swirl atomizer used in aircraft gas turbine engines. The test fuels are characterized in detail and all fuels meet current ASTM D7566 specifications. The experiments are conducted by discharging fuel spray into quiescent atmospheric air in a fuel spray booth to obtain spray characteristics such as fuel discharge behaviour, spray cone angle, breakup behaviour of swirling fuel sheet and spray drop size distribution. The characteristics of sheet breakup are deduced from the captured images of biofuel sprays and the measurements of spray droplet size distribution are obtained using Spraytec (laser-diffraction instrument). A systematic comparison is made between the biofuel sprays and the 100% Jet A-1 (conventional aviation kerosene) sprays to evaluate the drop-in feature of the biofuels. All the measured spray characteristics of the biofuel sprays follow the Jet A-1 both in qualitative and quantitative terms which ensure the drop-in nature of the tested biofuels. The minor differences observed in the comparison of the quantitative spray measurements are attributed to the variation in the fuel properties. This claim is supported using the predictions obtained from the liquid film breakup model and the empirical correlation reported in the literature for the determination of sheet breakup characteristics and mean drop size for sprays discharging from simplex swirl atomizers.
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Vankeswaram, Sai Krishna. "Atomization characteristics of alternative aviation biofuels, Jet A-1, and water from a hybrid airblast atomizer." Thesis, 2022. https://etd.iisc.ac.in/handle/2005/5663.
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Studies on the atomization of sustainable aviation fuels (SAF) from aircraft engine atomizers are essential to replace the present fossil type jet fuel to counter the rise in aviation-caused CO2 emissions in the atmosphere. The characteristics of spray droplets resulting from the breakup of liquid film in atomizers are crucial for the description of primary atomization process and combustion dynamics in aircraft engines. The thesis investigates the atomization of camelina- and jatropha-derived drop-in aviation biofuels from a hybrid airblast atomizer (HAA) used in aircraft jet engines. The main focus of the study is on the evaluation of spray droplet characteristics in the near-region of liquid film breakup. The experiments are carried out in a spray test facility. The images of sprays at different flow conditions are captured using backlighted shadowgraphy technique. The measurements of spray droplet characteristics are obtained using phase Doppler interferometry (PDI) and Spraytec at different spatial locations of the spray below the atomizer exit.
In the first part of the study, extensive experiments of liquid atomization from the HAA using water are conducted. The size and velocity characteristics of droplets resulted from the liquid film breakup in the simplex swirl atomizer (central atomizer in the HAA), measured within millimetre distance from the actual location of the liquid film breakup, are analysed. The mean axial velocity of the spray droplets measured at the film breakup point is independent of droplet size, which is different from the correlation characteristics of the spray droplets observed in other regions of the spray. The linear film breakup theory overpredicts Sauter mean diameter (SMD) of the spray measured at the breakup point significantly, and an existing scaling law for the determination of volume median diameter of the spray captures the present experimental trend of the droplet size recorded at the breakup point. The droplet size distribution measured at the breakup point is well described by a Gamma distribution with index parameter n governing the corrugation features of ligaments formed in the film breakup.
Further, by using the self-similarity analysis of droplet size and velocity, the demarcation region between the near- and far-region of liquid film breakup in the spray is established. A systematic comparison of spray characteristics in the near- and far-region of the liquid film breakup is reported.
In the second part of the study, the atomization characteristics of water and drop-in aviation biofuel sprays from the HAA is carried out. The droplet characteristics in the near-region of liquid film breakup are obtained at a distance 19 mm from the atomizer exit using Spraytec. The present droplet size data compare well with the predictions obtained using previously reported empirical correlation with a modified proportionality constant. The spray characteristics of the aviation biofuel sprays from the HAA are almost same as that of the standard fuel (Jet A-1) spray, which confirms the drop-in behavior of the chosen alternative fuels. By using the present experimental data of HAA spray from six experimental fluids, an empirical correlation for the estimation of nondimensionalized SMD in terms of liquid and gas Weber numbers and Ohnesorge number is proposed
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(9778397), Md Abul Kalam Azad. "Experimental investigation of CI engine performance, emissions and combustion using advanced biofuels." Thesis, 2016. https://figshare.com/articles/thesis/Experimental_investigation_of_CI_engine_performance_emissions_and_combustion_using_advanced_biofuels/16556727.
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There is an ongoing interest in developing new alternative fuels (such as biofuel) for both aviation and road transport sectors to meet increasing energy demand and assist in reducing greenhouse gas (GHG) emissions. The major contribution of this work is to develop an aviation biofuel from a new feedstock and create the best possible biodiesel-diesel blends for the transport sector. This study focuses on improving engine performance and reducing emissions by enhancing combustion efficiency using these newly developed fuels without any modification of the modern engine. The combustion and emissions were closely monitored to evaluate the pollutants formation in a compression ignition (CI) engine. Better performing fuels were identified and their tribological behaviour was also studied to assess their impact on engine life.
A wide range of biofuel feedstocks (over 150 species) was initially investigated to identify the most prospective feedstocks for producing biodiesels. The study eventually identified six prospective feedstocks namely Mandarin peel waste, Crambe, Tamanu, Borage, Waste Avocado flesh and Bush nut for biofuel production. The biofuels were produced in the laboratory from these selected feedstocks. The fatty acid methyl esters (FAMEs) composition and physio–chemical properties of these newly produced biofuels were evaluated using ASTM and EN standards.
The fuel properties of these biodiesels revealed that the properties of the Mandarin biofuel closely fit with the properties of commercial jet fuel with a calorific value of 44.66 MJ/kg (4.3% higher than commercial jet fuel) and a higher flash point of 52 °C. This biofuel has a lower viscosity (about 2.13 mm2/s at minus 20 degree C.) which is desirable and is self–oxygenated and sulphur free. Therefore, it is seen as a prospective new source of aviation biofuel production which is a new finding. This has not been studied earlier.
As an aviation engine was not available, Mandarin aviation biofuel was tested in a lean diesel engine and showed excellent performance and a large reduction in engine emissions. It can achieve reductions of up to 30.0% CO, about 33.5% HC and around 19.2% PM (particulate matter) at full load with variable speed and 33.0% CO, 32.8% HC, 28.5% PM emission reduction at variable load as compared to ultra – low – sulphur diesel (ULSD) by blending 20% with fossil fuel.
Other biodiesel (Crambe, Tamanu, Borage, Avocado, Bush nut) blends (B5 to B20) were also tested in a four stroke diesel engine to evaluate the performance and emission parameters at different operating and load conditions. The results revealed that Avocado biodiesel shows overall better performance (about 0.50% less BP, 0.83% more BSFC, and 0.18% less BTE as compared to ULSD at full load and rated speed) compared to other fuels. However, Crambe, Borage, and Bush nut also show close performance with Avocado biodiesel. Blending up to 20% of this biodiesel can reduce emissions by up to about 50% CO, 27% HC and 36% PM, however it increases NOx emission by about 26% compared to ULSD at full load and rated speed. On the other hand, Tamanu biodiesel blends show poor engine performance though emission reduction is comparable with other biodiesels at the same operating conditions.
For further improvement in engine performance and emission reduction this study developed four mixture blends by combining two biodiesels (totalling 5% at different proportions) and paraffin as an additive at 4% with the remaining 91% being ULSD. The mixture blends are described as ManCr_Pa (Mandarin-Crambe_Paraffin), TaMan_Pa (Tamanu-Mandarin_Paraffin), BoMan_Pa (Borage-Mandarin_Paraffin) and AvBn_Pa (Avocado-Bush nut_Paraffin). The mixture blends show improved performance compared to each B5 blend and significantly reduce emissions like B20 blends due to their improved fuel properties. Among these mixture blends, the Avocado-Bush nut and paraffin (AvBn_Pa) ternary mixture demonstrates comparable performance with ULSD. It reduces about 48.0% CO, 30.0% HC, 40.0% PM emissions compared to ULSD. This equates to about 16.0% CO, 8.7% HC and 28.0% PM more reduction of emissions compared to an Avocado B5 blend. This mixture blend produces about 9% less NOx compared to the B5 blend of Avocado biodiesel. On the other hand, the ManCr_Pa mixture blend reduces about 62% HC emission compared to ULSD with about 12% lower NOx emission.
The advanced combustion analysis was done on the better performing blends (i.e. for ManCr_Pa and AvBn_Pa mixture blends) to evaluate pollutant formation mechanisms during combustion. The results revealed shorter ignition delay and longer combustion duration for AvBn_Pa. This blend also exhibits higher cylinder pressure and higher heat release rate with a longer duration of the diffusion combustion phase. Additionally, a knocking characteristic was identified for ManCr_Pa mixture blend. The tribological characteristics such as friction, wear, lubrication stability and metal surface morphology were also evaluated using high-resolution SEM/EDX microscopy to assess energy savings, engine reliability, and impacts on engine life.
This study revealed an excellent tribological performance of AvBn_Pa blend compared to ULSD with about 21% less friction coefficient at steady state condition, around 19% less wear scar diameter, higher lubrication film stability, as well as less wear debris and metal corrosion. The study concluded that AvBn_Pa blend is the best mixture blend in all aspects of performance considered, namely emission reduction, improved combustion and tribological behaviour for a sustainable environment as well as sustainable engine health for the transport sector.
The study will provide useful information and guidelines to biofuel stakeholders, the transport sector, engine designers, the aviation industry and policy makers involved with newly developed aviation biofuels and other biodiesel usage in a full-scale diesel engine. It will provide new opportunities to future researchers to develop Mandarin aviation biofuel as a commercial aviation fuel. This research will help engine designers to develop more efficient and sustainable engines and to customise newly developed biodiesels for application in the transport sector.
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(6796532), Petr Vozka. "CHEMISTRY – PERFORMANCE CORRELATIONS IN ALTERNATIVE AVIATION FUELS TOWARDS A SUSTAINABLE FUTURE." Thesis, 2019.
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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.
Book chapters on the topic "Alternative aviation biofuels"
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"Standard and Alternative Fuel Specifications." In Biofuels for Aviation, 351–57. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-12-804568-8.00023-8.
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Cortez, Luís Augusto Barbosa, Francisco Emílio Baccaro Nigro, André M. Nassar, Heitor Cantarella, Luiz Augusto Horta Nogueira, Márcia Azanha Ferraz Dias de Moraes, Rodrigo Lima Verde Leal, Telma Teixeira Franco, and Ulf Schuchardt. "TECHNOLOGY ALTERNATIVES." In Roadmap for sustainable aviation biofuels for Brazil — A Flightpath to Aviation Biofuels in Brazil, 183–200. Editora Edgard Blücher, 2014. http://dx.doi.org/10.5151/blucheroa-roadmap-010.
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Palmeros Parada, Mar, Wim H. van der Putten, Luuk A. M. van der Wielen, Patricia Osseweijer, Mark van Loosdrecht, Farahnaz Pashaei Kamali, and John A. Posada. "Sustainability tensions and opportunities for aviation biofuel production in Brazil." In Sustainable Alternatives for Aviation Fuels, 237–62. Elsevier, 2022. http://dx.doi.org/10.1016/b978-0-323-85715-4.00007-0.
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Lewis, Kristin C., Dan F. B. Flynn, and Jeffrey J. Steiner. "Biofuel feedstocks and supply chains: how ecological models can assist with design and scaleup." In Green Aviation: Reduction of Environmental Impact Through Aircraft Technology and Alternative Fuels, 247–68. CRC Press, 2018. http://dx.doi.org/10.1201/b20287-12.
Full textConference papers on the topic "Alternative aviation biofuels"
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Costa, Mário, Bruno Pizziol, Miguel Panao, and André Silva. "Multiple Impinging Jet Air-Assisted Atomization." In ILASS2017 - 28th European Conference on Liquid Atomization and Spray Systems. Valencia: Universitat Politècnica València, 2017. http://dx.doi.org/10.4995/ilass2017.2017.4737.
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The growth of the aviation sector triggered the search for alternative fuels and continued improvements in thecombustion process. This work addresses the technological challenges associated with spray systems and theconcern of mixing biofuels with fossil fuels to produce alternative and more ecological fuels for aviation. This workproposes a new injector design based on sprays produced from the simultaneous impact of multiple jets, using anadditional jet of air to assist the atomization process. The results evidence the ability to control the average dropsize through the air-mass flow rate. Depending on the air-mass flow rate there is a transition between atomizationby hydrodynamic breakup of the liquid sheet formed on the impact point, to an aerodynamic breakup mechanism,as found in the atomization of inclined jets under cross-flow conditions. The aerodynamic shear breakupdeteriorates the atomization performance, but within the same order of magnitude. Finally, our experiments showthat mixing a biofuel with a fossil fuel does not significantly alter the spray characteristics, regarded as a stepfurther in developing alternative and more ecological fuels for aero-engines.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4737
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Kumar, Manish, and Srinibas Karmakar. "Comparison of Atomization Characteristics of Jet A-1 and Alternative Aviation Fuels Using High-Speed Imaging Technique." In ASME 2019 Gas Turbine India Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gtindia2019-2747.
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Abstract Environmental pollution from gas turbine engines is becoming a serious concern recently because of the steep growth in the aviation sector globally. Therefore, potential alternative fuels which can partially or fully replace fossil-based jet fuel are getting significant attention. However, the search for suitable candidate fuels which can fulfill the requirement in terms of fuel properties and combustion performance is continuing. The present study deals with an experimental investigation of atomization characteristics of Jet A-1, butanol, and butyl butyrate in quiescent atmospheric air. A high-speed imaging technique has been adopted to make a comparison of ligament breakup characteristics and droplet formation of these alternative biofuels with that of Jet A-1. Various fuel properties, including density, viscosity, and surface tension, are compared. An effort is made to understand how the variation in fuel properties influences the atomization mechanism of each fuel. The surface tension seems to be similar for these three fuels with a slight variation in density. However, there is a significant variation in viscosity. Viscosity appears to play a major role in the difference observed in ligament length and droplet formation. Due to the higher viscosity of butanol, the droplet formation seems to be delayed compared to Jet A-1, whereas the lower viscosity of butyl butyrate promotes faster droplet formation. The effect of blending of these biofuels with Jet A-1 on atomization characteristics will be compared with that of Jet A-1.
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Cromarty, Jason, and Sylvester Abanteriba. "Utilisation of Bio-Fuels in Aviation Gas-Turbine Engines: An Experimental and Theoretical Evaluation." In ASME 2009 Fluids Engineering Division Summer Meeting. ASMEDC, 2009. http://dx.doi.org/10.1115/fedsm2009-78589.
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An experimental and theoretical investigation was undertaken to identify and evaluate the key technical issues surrounding the ‘drop-in’ utilisation of alternative bio-fuels in aviation gas-turbine propulsion systems. Region-suitable biofuels were identified and suitability evaluated based on the following three criteria: ‘drop-in’ capability, environmental and economic sustainability and industrialisation prospects. Bio-fuel engine performance will be evaluated based on the specific fuel consumption, specific thrust, nature and quantity of emissions through theoretical modelling. This paper outlines a variety of different bio-fuel type options that were investigated. By using engineering and scientific methodology the fuels were evaluated to verify their suitability for gas-turbine aviation use. The eventual bio-fuel selected for further evaluation was a locally produced mustard seed oil derivative bio-fuel which was blended at various blend ratios with standard Jet A-1 turbine fuel. Verification testing processes for future investigation are detailed. In addition to engine performance evaluation endeavours, this paper also seeks to address and offer recommendations in the areas of bio-fuel production, transport, storage, certification and emissions.
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Lokesh, Kadambari, Vishal Sethi, Theoklis Nikolaidis, and Devaiah Karumbaiah. "System Level Performance and Emissions Evaluation of Renewable Fuels for Jet Engines." In ASME 2014 Gas Turbine India Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gtindia2014-8107.
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Incessant demand for fossil derived energy and the resulting environmental impact has urged the renewable energy sector to conceive one of the most anticipated sustainable, alternative “drop-in” fuels for jet engines, called as, Bio-Synthetic Paraffinic Kerosene (Bio-SPKs). Second (Camelina SPK & Jatropha SPK and third generation (Microalgae SPK) advanced biofuels have been chosen to analyse their influence on the behaviour of a jet engine through numerical modelling and simulation procedures. The thermodynamic influence of each of the biofuels on the gas turbine performance extended to aircraft performance over a user-defined trajectory (with chosen engine/airframe configuration) have been reported in this paper. Initially, the behaviour of twin-shaft turbofan engine operated with 100% Bio-SPKs at varying operating conditions. This evaluation is conducted from the underpinning phase of adopting the chemical composition of Bio-SPKs towards an elaborate and careful prediction of fluid thermodynamics properties (FTPs). The engine performance was primarily estimated in terms of fuel consumption which steers the fiscal and environmental scenarios in civil aviation. Alternative fuel combustion was virtually simulated through stirred-reactor approach using a validated combustor model. The system-level emissions (CO2 and NOx) have been numerically quantified and reported as follows: the modelled aircraft operating with Bio-SPKs exhibited fuel economy (mission fuel burn) by an avg. of 2.4% relative to that of baseline (Jet Kerosene). LTO-NOx for the user-defined trajectory decreased by 7–7.8% and by 15–18% considering the entire mission. Additionally, this study reasonably qualitatively explores the benefits and issues associated with Bio-SPKs.
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Shafagh, Ida, Kevin J. Hughes, Elena Catalanotti, Zhen Liu, Mohamed Pourkashanian, and Chris W. Wilson. "Experimental and Modelling Studies of the Oxidation of Surrogate Bio-Aviation Fuels." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45982.
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Jet fuels currently in use in the aviation industry are exclusively kerosene-based. However, potential problems regarding security of supply, climate change and increasing cost are becoming more significant, exacerbated by the rapidly growing demand from the aviation sector. Biofuels are considered one of the most suitable alternatives to petrochemical-based fuels in the aviation industry in the short to medium term, since blends of biofuel and kerosene provide a good balance of properties currently required from an aviation fuel. Experimental studies at a variety of stoichiometries using a flat flame burner with kerosene and kerosene/biofuel blends have been performed with product analysis by gas sampling and laser induced fluorescence detection of OH, CO and CO2. These studies have been complemented by modelling using the PREMIX module of Chemkin to provide insights into and to validate combined models describing the oxidation chemistry of surrogate fuels depicting kerosene, fatty acid methyl ester biofuels and Fischer-Tropsch derived fuels. Sensitivity analysis has identified important reactions within these schemes which where appropriate have been investigated by molecular modelling techniques available within GAUSSIAN 03.
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Uryga-Bugajska, I., M. Pourkashanian, D. Borman, E. Catalanotti, L. Ma, and C. W. Wilson. "Assessment of the Performance of Alternative Aviation Fuel in a Modern Air-Spray Combustor (MAC)." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68772.
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Recent concerns over energy security and environmental considerations have highlighted the importance of finding alternative aviation fuels. It is expected that coal and biomass derived fuels will fulfil a substantial part of these energy requirements. However, because of the physical and chemical difference in the composition of these fuels, there are potential problems associated with the efficiency and the emissions of the combustion process. Over the past 25 years Computational Fluid Dynamics (CFD) has become increasingly popular with the gas turbine industry as a design tool for establishing and optimising key parameters of systems prior to starting expensive trials. In this paper the performance of a typical aviation fuel, kerosene, an alternative aviation fuel, biofuel and a blend have been examined using CFD modelling. A comprehensive understanding of the kinetics of the reaction for bio aviation fuels at both high and low temperature is necessary to perform reliable simulations of ignition, combustion and emissions in an aero-engine. A novel detailed reaction mechanism was used to represent the aviation fuel oxidation mechanism. The fuel combustion is calculated using a 3D commercial solver using a mixture fraction/pdf approach. Firstly, the study demonstrates that CFD predictions compare favourably with experimental data obtained by QinetiQ for a Modern Airspray Combustor (MAC) when used with traditional jet fuel (kerosene). Furthermore, the 3D CFD model has been refined to use the laminar flamelet model (LFM) approach that incorporates recently developed chemical reaction mechanisms for the bio-aviation fuel. This has enabled predictions for the bio-aviation fuel to be made. The impact of using the blended fuel has been shown to be very similar in performance to that of the 100% kerosene, confirming that aircraft running on 20% blended fuel should have no significant reduction in performance. It was also found that for the given operating conditions there is a significant reduction in performance when 100% biofuel is used. Additionally, interesting predictions were obtained, related to NOx emissions for the blend and 100% biofuel.
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Sakthikumar, Ramachandran, Deivandren Sivakumar, B. N. Raghunandan, and John T. C. Hu. "Atomization Characteristics of Jatropha-Derived Alternative Aviation Fuels From Aircraft Engine Injector." In ASME 2017 Gas Turbine India Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gtindia2017-4882.
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Search for potential alternative jet fuels is intensified in recent years to meet stringent environmental regulations imposed to tackle degraded air quality caused by fossil fuel combustion. The present study describes atomization characteristics of blends of jatropha-derived biofuel with conventional aviation kerosene (Jet A-1) discharging into ambient atmospheric air from a dual-orifice atomizer used in aircraft engines. The biofuel blends are characterized in detail and meet current ASTM D7566 specifications. The experiments are conducted by discharging fuel spray into quiescent atmospheric air in a fuel spray booth to measure spray characteristics such as fuel discharge behavior, spray cone angle, drop size distribution and spray patternation at six different flow conditions. The characteristics of spray cone angle are obtained by capturing images of spray and the measurements of spray drop size distribution are obtained using laser diffraction particle analyzer (LDPA). A mechanical patternator system comprising 144 measurement cells is used to deduce spray patternation at different location from the injector exit. A systematic comparison on the atomization characteristics between the sprays of biofuel blends and the 100% Jet A-1 is presented. The measured spray characteristics of jatropha-derived alternative jet fuels follow the trends obtained for Jet A-1 sprays satisfactorily both in qualitative and quantitative terms.
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de Greyt, Wim. "Requirements and Solutions for the Pretreatment of  HVO Feedstocks." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/ghem2777.
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Hydrotreated Vegetable Oils (HVO) and Hydoprocessed Esters and Fatty Acids (HEFA) are premium quality biofuels that are produced via hydrotreatment of renewable (waste) feedstocks from vegetable and animal origin. HVO/HEFA production is increasing rapidly worldwide and this is supported by several growth drivers. HVO/HEFA has a better functionality compared to classical biodiesel based on fatty acid methyl esters (FAME)  and it is fully compatible with mineral diesel. HVO/HEFA fractions can also be used as sustainable aviation fuel (SAF). All major (European) airlines have recently announced that they will start using increasing volumes of SAF on voluntary basis in anticipation of a future compulsory SAF proportion. Initially, HVO was mainly produced from food-grade oils (e.g. palm oil, soybean oil). However for sustainability but also economical & political reasons, producers are increasingly looking for alternative (lower quality – non food) feedstocks such as UCO, waste animal fats, by-products from edible/technical oil refining, distillation pitches and even non-glyceride feedstocks.
Independent of the applied technology, all HVO feedstocks need to be pre-treated before they can enter the hydrotreatment process. Specific pre-treated feedstock specifications depend on the HVO technology provider. In general, the pre-treatment is necessary to remove impurities such as P and metals but also nitrogen and chlorine containing components in order to increase the HVO catalyst life time and to avoid corrosion problems in the plant.
Pre-treatment of ‘good quality’ feedstocks (vegetable oils, used cooking oils, some animal fats) is pretty straightforward and can be accomplished by a series of processes that are already known from the edible oil refining processes. Proper pre-treatment of lower quality feedstocks is much more challenging and requires a more complex, multi-stage process that consists of a series of dedicated unit operations. HVO/HEFA producers are very interested in such efficient pre-treatment processes as their availability and industrial applicability will finally determine if/to which extend a given low quality feedstock can be used which will directly impact the economical viability of their HVO plant.
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Catalanotti, E., K. J. Hughes, M. Pourkashanian, I. Uryga-Bugajska, and A. Williams. "Development of a High Temperature Oxidation Mechanism for Bio-Aviation Fuels." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68667.
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Almost all current civil and military aviation around the world use a kerosene-type fuel. However one of the alternatives is to use a mixture of petrochemicals and biofuel, especially methyl esters derived from vegetable oil (Fatty Acid Methyl Esters, FAMEs) that given their properties appear to be one of the most suitable for Aviation fuels. Studies were conducted to develop a fundamental and detailed reaction mechanism for the combustion of bio-aviation fuel through a combination of the existing kerosene based reaction mechanism developed previously by the authors (Aviation Fuel Reaction Mechanism v1.1), along with published chemical kinetic mechanisms for methylbutanoate (MB). Methylbutanoate is the simplest FAME that exhibits similar patterns of reactivity to FAME’s of longer carbon chain length typical of those derived from vegetable oils, furthermore it has been the subject of several studies to provide chemical kinetic mechanisms to predict its oxidation behavior. Evaluations of the combined reaction mechanism have been performed using CHEMKIN™ and similar software simulating high temperature/pressure conditions. A comparison between the oxidation processes of the Kerosene and Bio-Aviation fuel was carried out, along with sensitivity analysis to provide insight into some of the differences observed. A similar behaviour was observed for blends of 20%MB/80%Kerosene in the combustion conditions studied, indicating that combustion in current aircraft engines would not be adversely affected by using such a blend.
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Munzar, Jeffrey D., Bradley M. Denman, Rodrigo Jiménez, Ahmed Zia, and Jeffrey M. Bergthorson. "Flame Speed and Vapor Pressure of Biojet Fuel Blends." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94650.
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An understanding of the fundamental combustion properties of alternative fuels is essential for their adoption as replacements for non-renewable sources. In this study, three different biojet fuel mixtures are directly compared to conventional Jet A-1 on the basis of laminar flame speed and vapor pressure. The biofuel is derived from camelina oil and hydrotreated to ensure consistent elemental composition with conventional aviation fuel, yielding a bioderived synthetic paraffinic kerosene (Bio-SPK). Two considered blends are biofuel and Jet A-1 mixtures, while the third is a 90% Bio-SPK mixture with 10% aromatic additives. Premixed flame speed measurements are conducted at an unburned temperature of 400K and atmospheric pressure using a jet-wall stagnation flame apparatus. Since the laminar flame speed cannot be studied experimentally, a strained (or reference) flame speed is used as the basis for the initial comparison. Only by using an appropriate surrogate fuel were the reference flame speed measurements extrapolated to zero flame strain, accomplished using a direct comparison of simulations to experiments. This method has been previously shown to yield results consistent with non-linear extrapolations. Vapor pressure measurements of the biojet blends are also made from 25 to 200°C using an isoteniscope. Finally, the biojet blends are compared to the Jet A-1 benchmark on the basis of laminar flame speed at different equivalence ratios, as well as on the basis of vapor pressure over a wide temperature range, and the suitability of a binary laminar flame speed surrogate for these biojet fuels is discussed.