Fuel Research Articles

ASTM approves new bio-jet fuel pathway

ASTM approves new bio-jet fuel pathway

Simulation Study of Effect of Ejection Ratio on Combustion of a Stirling Engine Fueled with Biodiesel

Simulation Study of Effect of Ejection Ratio on Combustion of a Stirling Engine Fueled with Biodiesel

Quantification of fuel material in litter at Eucalyptus plantations in Aquidauana, MS

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Modeling Surface Riblets Skin Friction Reduction Effect with the Use of Computational Fluid Dynamics

Towards the minimization of fuel consumption and aicraft emissions reduction, many disruptive technologies have been proposed in aviation industry regarding the improvement of aircraft aerodynamic performance. Among others, these technologies involve innovative passive and active flow control methodologies and techniques. A passive flow control methodology which is studied in the current work is the implementation of riblets, which are inspired by shark skin morphology, on a NACA 0012 airfoil. The main purpose of riblets is to alter the boundary layer characteristics near the wall region in such a way that the total skin friction decreases, resulting in an overall drag reduction of the aircraft with a straightforward impact on fuel consumption and thus emissions. The riblets are implemented in the Reynolds Averaged Navier Stokes equations with appropriate source terms in the turbulent dissipation transport equation. Two turbulence models are used, the k-? SST linear eddy viscosity model and the Baseline Reynolds Stress model which also uses the transport equation of the specific rate of turbulence dissipation (?). The computational results are compared with available experimental data of NACA 0012 with surface riblets attached. Drag and skin friction coefficients are presented for various angles of attack and the maximum potential benefit from riblet use is evaluated regarding aerodynamic performance and consequently reduction of emissions and fuel consumption.

A Novel Optimisation Framework to Support Increased Uptake of Low Carbon Industrial Energy Systems

Combustion of fossil fuels in industrial energy systems (IES) is responsible for over 45 % of CO2 emissions. Low Carbon IES will go a long way in achieving the climate goal of the Paris Agreement; yet, uptake of concepts to deliver low carbon IES is slow. Cost and emissions minimisation based optimisation frameworks applied to design and assess IES, though important, are not able to directly quantify the uptake of new technologies to deliver low carbon IES in a country or region. This work presents a novel MINLP framework capable of directly maximing the adoption of low carbon IES within a country and region whilst determining the optimal energy flows and associate costs. The method is applied to a case stufy of 6,181 energy systems in wastewater treatment plants (WWTP) in 27 EU countries to support increased adoption of technology switching (from combustion to electrochemistry), and fuel switching (from natural gas to biogas). Results show that without policy interventions uptake of these measures is only in 0.2 % of the plants located in Denmark, with policy intervention uptake increases to 60 % in more countries. The novel framework shows how the uptake of a new cleaner technology in a country or region can be accelerated.

Synthesis of Large-Scale Supply Networks for Complete Long-term Transition from Fossil to Renewable-based Production of Energy and Bioproducts

This contribution presents the synthesis of sustainable larger-scale supply networks to produce alternative energy and bioproducts across an entire system’s lifetime. In particular, production of food, first, second and third generation of biofuels, hydrogen, and renewable electricity are considered. Corn and wheat grain are used for production of food; corn stover, wheat straw, miscanthus, forest residue, algae oil and waste cooking oil are biomass and waste sources for the manufacture of bioproducts; and solar, wind and geothermal sources for electricity production. The objective of supply network synthesis is the maximization of Sustainability Net Present Value, which is a sustainability metric composed of economic, environmental and social net present values. The dynamic mixed-integer linear programming problem is formulated as a multi-period model where i) monthly time periods are used for the manufacture of biomass and bioproducts, while ii) daily, hourly and monthly periods are used for the production of electricity. A case study of EU-27 is considered and gradual energy transition from the current energy supply to 100 % renewable-based production of fuels and electricity over a time horizon of 40 y is investigated. The results of this study indicate that long-term transition from fossil to renewable-based generation of electricity, fuels and bioproducts is possible to a large extent. The results suggest an optimal selection of types, locations and dynamics of technology installations across the EU in order to achieve energy transition in the transport and electricity sectors.

Optimization of Biodiesel Production from Neem Oil using KOH Supported with Activated Carbon

Fossil fuel reduction and environmental degradations are the two crises that the world threatened by generally and UAE specifically. Biodiesel is a fuel produced through a chemical reaction of animal fat or vegetable oil with alcohol, and consider a potential alternative of diesel engines. However, this reaction needs a catalyst to complete successfully. The current article contains transesterification of neem oil with KOH catalyst supported with activated carbon (KOH/AC). This study included experimental work by applying KOH/AC as an effective catalyst for transesterification of local neem oil. The response surface methodology (RSM) software tool was used in this study to determine the optimal conditions of reaction time, amount of catalyst and ratio of methanol to oil in order to obtain the highest percentage of biodiesel product. The optimal settings obtained were 60 min reaction time, a ratio of oil to methanol 1:6 and 1 wt% of catalyst, which lead to the highest yield of biodiesel (100 wt%). The specific features of biodiesel were checked and compared to ASTM standards.

Cleaner Process and Entrainer Screening for Bioethanol Dehydration by Heterogeneous Azeotropic Distillation

Greenhouse gas footprint of fuels is due to both the burning fuel and its production process. Bioethanol is a sustainable biofuel but it is obtained diluted in water and its dehydration consumes large amounts of energy. Heterogeneous azeotropic distillation is a well-known suitable option for dehydration of bioethanol (separation of ethanol from water). Many entrainers for this process are studied in literature but unfortunately, there is no critical comparison in terms of the corresponding process efficiency. The distillation efficiency assessment is necessary as it has a great impact on the energy consumption and sustainability of bioethanol production. The process scheme and entrainer are screened following a fast-to-rigorous procedure: feasibility checking using the infinite/infinite analysis, screening based on the Distillation Sequence Efficiency (DSE) method and rigorous simulation using AspenPlus®. Different process schemes are assessed taking into account also that some gasoline additives, used as entrainers, could remain in bioethanol, which is to be included in the gasoline formulation. Some examples of commonly used ethers as gasoline additives are methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), diisopropyl ether (DIPE) and tert-amyl methyl ether (TAME). The study shows that when the entrainer is a gasoline additive, collecting the distillation product as a mixture of ethanol and additive consumes 27 % less energy than collecting pure ethanol. Performing the ethanol dehydration and gasoline additive mixing together in the same process leads to a 27 % decreasing of CO2 emissions.

Economic Analysis of Syngas Production by Coupling Coal Gasification Wastewater Treatment and Solid Oxide Cell System

Coal is the main energy source in China, and coal chemistry wastewater treatment has always been a research hotspot. For the large amount of concentrated organic wastewater, high cost caused by complex treatment process is the key issue. In this paper, the fixed bed Lurgi gasifier wastewater coupled with solid oxide cells (SOCs) system is employed for its treatment. Based on Aspen Plus software, the purified methane from marsh gas is sent to solid oxide fuel cell (SOFC) for electricity generation. While carbon dioxide separated from biogas purification and acid gas removal enters solid oxide electrolysis cell (SOEC) to produce syngas by co-electrolysis with steam.The simulation results show that the efficiency of SOFC is 48.5 %. The generated electric energy can be used for auxiliary equipment in wastewater treatment and SOEC to produce syngas, recycling of carbon dioxide. SOEC with wind power of 12.84 MW is enough to treat the waste gas generated by the 1,100 t/h Lurgi gasification wastewater treatment process. Economically, the cost of producing syngas, with high purity and fewer contaminant contents, is about 0.126 $/Nm3. It can be used to produce various chemicals, so as to further improve the economic benefit of wastewater treatment.

Surface Characterisation of Estonian Oil Shale Semi-Coke

Oil shale is a low-grade fossil fuel that has been used in Estonia mostly for electricity and shale oil production. The conventional use of oil shale results in a vast amount of carbon dioxide emissions urging to find alternative ways for sustainable utilisation of oil shale and develop new technologies. Since oil shale contains relatively high amount of organic matter it should be suitable for producing porous carbonised material (semi-coke) that has high surface area and can be used as an adsorbent in various applications. The aim of this research is to determine the effect of thermal treatment conditions on the specific surface area (SSA) of semi-coke. Estonian oil shale from Ojamaa underground mine was pyrolysed in a batch reactor using different temperatures in the range of 550 to 900 °C and atmospheres (N2 and CO2). The surface properties (BET SSA, pore volume and pore size distribution) of obtained samples were studied using N2 adsorption. The results showed that when the pyrolysis temperature was raised in N2 environment, larger SSA of the sample was obtained – it increased from 12 m2/g (pyrolysed at 550 °C) to 31 m2/g (pyrolysed at 900 °C). At higher temperatures the increase of pores less than 5 nm in diameter was also noticed. The semi-coke samples prepared in N2 environment had larger SSA compared to the ones prepared in CO2.

Influence of Fuel-Staging Ratio on Combustion Performance of Dual Fuel Combustor

Influence of Fuel-Staging Ratio on Combustion Performance of Dual Fuel Combustor

Review of Recent Advances of Wind Energy

This paper presents a review of the recent advances of the wind power. The wind power is a very clean and renewable alternative to the burning fossil fuels and has no impact on the environment. The energy scientists are in knowledge of the world needs to increase the clean energy sources. The impact of the classical process for generating the power on the environment has created a need for a strategic planning and development of the clean and sustainable power systems of generation. This paper focuses on the recent aspects of the wind power and the technology including several technical issues.

Effects of Co-Exposure to Noise and JP-4 Jet Fuel on Hearing Loss in Rats

Effects of Co-Exposure to Noise and JP-4 Jet Fuel on Hearing Loss in Rats

Fuel of Oil Lamp and Wick in the Period of the Three Kingdoms

Fuel of Oil Lamp and Wick in the Period of the Three Kingdoms

Local Current Density Distribution of Proton Exchange Membrane Fuel Cell and Its Research Prospects

Local Current Density Distribution of Proton Exchange Membrane Fuel Cell and Its Research Prospects

Combined supply of electricity and fuel at biogas plants ‒ economic efficiency of connection scenarios

Durch das Auslaufen der EEG-Vergutung sowie der starken Einschnitte bei der Forderung der Biogasverstromung im novellierten EEG 2017 steht die Biogasbranche vor der Frage, welche Anschlusskonzepte sowohl wirtschaftlich attraktiv als auch langfristig aussichtsreich sein konnten. Die Kraftstoffproduktion aus Biogas ware eines der moglichen Anschlussszenarien. In mehreren Studien wird bis 2050 eine Verschiebung der Biogasverwertung von der Verstromung hin zur Kraftstoffnutzung prognostiziert. Auch die Politik strebt eine hohere Umsetzung von Bioenergie im Kraftstoffsektor an. In diesem Beitrag werden daher Anschlussszenarien mit Strom- und Kraftstoffproduktion in Biogasanlagen okonomisch bewertet. Auserdem wird ein neuer Flexibilisierungsansatz mit anteiliger Strom- und Kraftstofferzeugung von jeweils 50 % an der Biogasverwertung untersucht. Mithilfe von flexibilisierten Verstromungsfahrplanen, lokalen Daten zum Kraftstoffbedarf von Fuhrparks und eines darauf basierenden Kraftstoff­erzeugungsfahrplans wurde der erforderliche Biogasspeichermehrbedarf, der Hochdruckspeicherbedarf sowie die notwendige Anlagenleistung fur die Kraftstoffproduktion ermittelt. Schlieslich wurden mehrere Anschlussszenarien fur eine reprasentative Modellbiogas­anlage nach der Kapitalwertmethode okonomisch bewertet. Beim Vergleich zeigte sich, dass die Anschlussszenarien mit Kraftstoffproduktion wirtschaftlicher sind als jene mit ausschlieslicher Stromproduktion. Je nachdem, wie die geplante nationale Umsetzung der Neufassung der europaischen Erneuerbare-Energien-Richtlinie (RED II) realisiert wird, kann sich die Wirtschaftlichkeit – insbesondere bei der Erhohung des Gulleanteils in der Substratzusammensetzung – deutlich verbessern.

Aerodynamic design optimization of an aircraft wing for drag reduction using computational fluid dynamics approach

The aircraft industry supports aviation by building aircraft and manufacturing aircraft parts for their maintenance. Fuel economization is one of the biggest concerns in the aircraft industry. The reduction in specific fuel consumption of aircraft can be achieved by a variety of means, simplest and more effective is the one to impose minor modifications in the aircraft main wing or the parts which are exposed to the air flow. This method can lead to a reduction in aerodynamic resistance offered by the air and have a smoother flight. The main objective of this study is to propose geometric design modifications on an existing aircraft wing which acts as a vortex generator and it can reduce the drag and increase lift to drag ratio, leading to lower fuel consumption. The NACA 2412 aircraft wing is modified and designed. Rigorous flow analysis is carried out using computational fluid dynamics based software Ansys Fluent. Results show that saw tooth modification to the main wing shows the best aerodynamic efficiency as compared to other modifications.

HollyFrontier opts for Topsoe's HydroFlex Solution to reduce cost-of-compliance with renewable fuel blending requirements

HollyFrontier opts for Topsoe's HydroFlex Solution to reduce cost-of-compliance with renewable fuel blending requirements

Community participation in the renewable energy sector in Tanzania: Community participation in the renewable energy sector

Community participation (CP) is emphasized in the planning and implementation of the various projects and sector. Renewable energy (RE) sector like other sectors requires community participation for its effectiveness and efficiency. This review aims at exploring the community participation in the renewable sector in Tanzania. Five themes were identified for through literature review where a Seven-Step Model for comprehensive literature review was used. These themes include (i) access to information on RE resources; (ii) community awareness of the RE technologies and related policies, laws, and regulations; (iii) RE as the source of employment opportunities; and (iv) RE as an alternative to fossil fuels and for poverty alleviation. These study revealed that despite the different efforts taken by the government and other energy stakeholders the community still lack enough information and awareness about renewable energy technologies, institutional and regulatory framework. However, the interesting issue is that renewable energy sectors play an important role in providing employment opportunities to the local communities. Moreover, the use of renewable energy has contributed to poverty alleviation. For instance, hydropower has an increase in electricity supply, solar energy has improved the local households’ standard of living, education and health services. It is recommended that the government and other energy stakeholders should cooperate to provide more information and awareness of renewable energy technologies to the community. This should be accompanied by the introduction of the national policy and law which is specifically for renewable energy to enable its development. Community participation (CP) is emphasized in the planning and implementation of the various projects and sector. Renewable energy (RE) sector like other sectors requires community participation for its effectiveness and efficiency. This review aims at exploring the community participation in the renewable sector in Tanzania. Five themes were identified for through literature review where a Seven-Step Model for comprehensive literature review was used. These themes include (i) access to information on RE resources; (ii) community awareness of the RE technologies and related policies, laws, and regulations; (iii) RE as the source of employment opportunities; and (iv) RE as an alternative to fossil fuels and for poverty alleviation. These study revealed that despite the different efforts taken by the government and other energy stakeholders the community still lack enough information and awareness about renewable energy technologies, institutional and regulatory framework. However, the interesting issue is that renewable energy sectors play an important role in providing employment opportunities to the local communities. Moreover, the use of renewable energy has contributed to poverty alleviation. For instance, hydropower has an increase in electricity supply, solar energy has improved the local households’ standard of living, education and health services. It is recommended that the government and other energy stakeholders should cooperate to provide more information and awareness of renewable energy technologies to the community. This should be accompanied by the introduction of the national policy and law which is specifically for renewable energy to enable its development.

The Determinants of Distribution of Credit: Evidence from Vietnam

Purpose: The issue of access to credit for private enterprises has been given an increased amount of attention given their crucial role in fueling...