Showing papers on "Alcohol fuel published in 2012"

Impact of alternative fuel properties on fuel spray behavior and atomization

Abstract: In order to verify and solve the problem of NOx and PM emissions, it is necessary to directly observe the internal combustion chamber of a diesel engine. Many studies have been performed in recent years to verify the macroscopic and microscopic behavior of the injected fuel spray because observing it is not easy due to the difficulties of the experiment. Researchers have investigated the spray characteristics for various diesel injector nozzles over a wide range of temperatures and pressure, but there is lack of evaluation for the spray characteristics for biodiesel. At a time when rapid rise of fuel prices and depleting hydrocarbon resources of the world have forced us to look for alternative fuels biodiesel produced by transesterification of non-edible vegetable oils is promising to be an important additive/substitute to petro diesel. Biodiesel being an oxygenated and sulfur-free fuel leads to more complete combustion and lower emissions. But, the energy content or net calorific value of biodiesel is less than that of diesel fuel; also it has higher viscosity and density, than diesel fuel. A considerable improvement in these properties can be obtained by mixing diesel and biodiesel and then using the blends. Biodiesel and biodiesel/petro diesel blends, with their higher lubricity levels, are increasingly being utilized as an alternative. Present paper analyzed the correlation of injection parameters that will affect the spray characteristics of biodiesel. Observations for analyzing the effect of injection parameters on spray cone angle, break up length and fuel penetration were made. Finally the performance and emissions tests were studied. Atomization and vaporization of fuel are greatly influenced by viscosity and density of fuel and these properties are temperature dependent. Thus fuel inlet temperature plays a very important role in fuel atomization process. At higher temperature viscosity of fuel decreases which enhances the atomization of biofuels.

An Experimental and Kinetic Modeling Study of Pyrolysis and Combustion of Acetone–Butanol–Ethanol (ABE) Mixtures

Abstract: The excellent fuel characteristics of bio-butanol are responsible for the renewed interest in the acetone–butanol–ethanol (ABE) fermentation process and the combustion and pyrolysis behavior of mixtures of acetone, butanol, and ethanol. Therefore, in this work, a detailed mechanism for the pyrolysis and oxidation of ABE is presented containing ∼350 species and more than 10,000 reactions. The mechanism is validated against newly acquired and published pyrolysis data for the ABE-mixture and the respective components. Excellent agreement is obtained between measured and simulated product yields as a function of the conversion. Laminar flame speed computations of alcohols and ABE complement the detailed comparisons of the pyrolysis data and allow for further validation of the combustion behavior of bio-butanol and its mixtures. Supplemental materials are available for this article. Go to the publisher's online edition of Combustion Science and Technology to view the free supplemental file.

High-Temperature Chemistry in Solid Oxide Fuel Cells: In Situ Optical Studies.

Abstract: Solid oxide fuels cells (SOFCs) are promising devices for versatile and efficient power generation with fuel flexibility, but their viability is contingent upon understanding chemical and material processes to improve their performance and durability. Newly developed in situ optical methods provide new insight into how carbon deposition varies with different hydrocarbon and alcohol fuels and depends on operating conditions. Some findings, such as heavier hydrocarbon fuels forming more carbon than lighter fuels, are expected, but other discoveries are surprising. For example, methanol shows a greater tendency to form carbon deposits than methane at temperatures below 800 °C, and kinetically controlled steam reforming with ethanol at high temperatures (∼800 °C) is less detrimental to SOFC performance than operating the device with dry methanol as the fuel. In situ optical techniques will continue to provide the chemical information and mechanistic insight that is critical for SOFCs to become a viable energy conversion technology.

Experimental determination of suitable ethanol–gasoline blend for Spark ignition engine

Abstract: Ethanol produced from biomass has high octane number and good antiknock characteristic, less ozone depletion potential and global warming potential than the pure gasoline, therefore it can be used as a blended fuel with gasoline fuel in the S.I. engine. In this paper the experimental investigation of four stroke petrol engine is carried out to analyze the engine performance and emission characteristics. Engine performance and exhaust emission are determined using different blend ratios of ethanol with gasoline (E0, E20, E40, E60, E80, and E100) to evaluate the most suitable blend. In this study the engine with compression ratio 10:1 is tested using pure gasoline and various blends by varying Brake power at constant engine rpm. Performance tests are conducted for total fuel consumption, brake specific fuel consumption, brake thermal efficiency and exhaust emissions. The exhaust emissions are analyzed for carbon monoxide (CO), and unburned hydrocarbons (HC). The results shows that blending of ethanol with gasoline increases fuel consumption, brake specific fuel consumption, brake thermal efficiencies, while the CO and HC concentration in the emissions of engine exhaust decreases considerably

A Novel Diesel Fuel Additive to Improve Fuel Properties and to Reduce Emissions

Abstract: Global air pollution is a serious threat caused by excessive use of fossil fuels for transportation. Despite the fact that diesel fuel is a big environmental pollutant as it contains different hydrocarbons, sulphur and crude oil residues, it is yet regarded as a highly critical fuel due to its wide applications. Nowadays, biodiesel as a renewable additive is blended with diesel fuel to achieve numerous advantages such as lowering CO2, and CO emissions as well as higher lubricity. However, a few key drawbacks including higher production cost, deteriorated performance and likelihood to increase nitrogen oxide emissions have also been attributed to the application of diesel-biodiesel blends. Expanded polystyrene (EPS), known as a polymer for packaging and insulation, is an ideal material for energy recovery as it holds high energy value (1 kg of EPS is equivalent to 1.3 liters of liquid fuel). In this study, biodiesel was applied as a solvent of expanded polystyrene (EPS) during a special chemical and physical treatment. Various percentages of EPS in biodiesel blended diesel were tested to evaluate the fuel properties, emissions and performance of CI engine. The results of the variance analysis revealed that the addition of the additive improved diesel fuel properties by increasing the flash point as well as the reduction of density and viscosity. Despite a 3.6% reduction in brake power, a significant decrease in brake specific fuel consumption (7.26%) and an increase in brake thermal efficiency (7.83%) were observed at the full load and maximum speed of the engine. Additionally, considerable reductions of CO, CO2, NOx and smoke were achieved.

Formulation of Canola-Diesel Microemulsion Fuels and Their Selective Diesel Engine Performance

Abstract: Vegetable oils have been considered as an alternative to diesel fuel due to their comparable properties and performance. However, the high viscosity of vegetable oil causes engine durability problems with long-term usage. Vegetable oil viscosity can be reduced by blending with diesel fuel in thermodynamically stable mixtures using microemulsion fuel formulation techniques. This work focuses on the formulation of microemulsion fuels comprising diesel fuel and canola oil as the oil phase with ethanol and sec-butanol as viscosity reducers as well as 1-octanol and oleyl amine as surfactant/cosurfactant. Selective tests on an instrumented diesel engine were performed for formulated microemulsion fuels and No. 2 diesel fuel for comparison. The results show that formulated microemulsion fuels have fuel properties that meet the ASTM requirements for viscosity, cloud point, and pour point for biodiesel. Even more important, they have phase stability over a wide range of temperatures (−10 to 70 °C). Although all of the microemulsion fuels showed higher fuel consumption than diesel fuel, some of the microemulsion fuels had significantly reduced CO and NOx emissions as well as reduced particulates when compared to baseline diesel fuel. The research demonstrates the potential of these microemulsion fuels as alternative to neat diesel fuel.

The Emission Characteristics of a CI Engine Fueled with a Biofuel Blend

Abstract: In this study, an alternative diesel fuel, of which chemical modification was made by transesterification with short chain methyl alcohols, was produced from cottonseed oil. The modified products were then evaluated according to their fuel chemical properties as compared to diesel fuel. The purpose of this study is to investigate the emission characteristics of the fuel blend of 75% cottonseed oil methyl ester with 25% diesel fuel in a single cylinder unmodified diesel engine. The effects of biofuel and diesel fuel blend on a direct injected, four strokes, and single cylinder diesel engine exhaust emissions were studied. The results showed on the emissions of the engine that there was about 36% reduction in CO, about 18% reduction in CO2, and about 15% reduction in NOx. These results show that B75 fuel has better emission characteristics than diesel fuel. The reduction exhaust emissions made B75 a suitable alternative fuel for diesel engines and could help in controlling air pollution.

Evolution of alcohol fuel blends towards a sustainable transport energy economy

Abstract: Work undertaken by Lotus Engineering and partners has shown that the miscibility of the low-carbon-number alcohols with gasoline provides a powerful tool to enable the introduction of methanol as a transport fuel in a wholly evolutionary manner. This is primarily facilitated by the fact that the CAFÉ regulations in the US (together with other incentives in other countries, such as Sweden) have created a situation in which there are 7-8 million E85/gasoline flex-fuel vehicles on the roads there, for which insufficient E85 can be provided at an affordable price. This paper will show that the introduction of methanol (which can be made extremely simply and cheaply from natural gas) into gasoline-ethanol mixtures, can be used to create drop-in fuels equivalent to E85 and can bring the price of an alcohol-based fuel for spark-ignition engines down to less than that of gasoline (on a per-unit-energy basis, before tax is applied). It can thus more than compete with that fuel. This opens up the possibility of using the US’s reserves of naturally gas (be it conventional or unconventional types such as shale) immediately to manufacture methanol to displace gasoline, as a bridge to a broader energy economy based on higher concentrations of methanol made from renewable sources. The vehicle work conducted has shown the possibility of realizing this state of affairs, and related laboratory tests on some of the potential fuel blends have similarly demonstrated that they possess some of the necessary characteristics to be truly ‘dropin’ alternatives to E85. These necessary characteristics are considered to be equal volumetric energy content (to enable compliance with on-board diagnostics requirements), equal octane numbers and latent heat (to provide invisibility to the combustion and air handling systems), and inherent miscibility with gasoline (to avoid the requirement to change the fundamental nature of the vehicle fuel system). A further requirement in practice is that the vehicles still be of adequate performance with regard to tailpipe emissions standards using the existing exhaust after treatment systems fitted to them. In the present work this is demonstrated by reporting data for oxides of nitrogen emissions (NOx) taken from a standard production Saab 9 certified to the EU5 emissions standard using ternary blends (such NOx emissions being especially important from a human health point of view in built-up areas), which shows that generally such emissions are significantly lower for all of the alcohol blends than for gasoline. All results are found to be well within the EU5 limits, with the gasoline results showing that the after treatment system was indeed functioning correctly.

Optimization of Direct 2-propanol Fuel Cell Performance Using Statistical Design of Experiments Approach

Abstract: Direct alcohol fuel cells have been attracting enormous research interest as power sources for vehicles and portable electronic devices because alcohols are readily available, their storage and transport can be easily handled with the existing fuel infrastructure, and they commonly have high mass-specific and volumetric energy densities. Methanol is the most studied fuel for direct alcohol fuel cells because methanol is readily available, it is structurally simple, and has a promising electrochemical activity. However, several research groups have also reported the use of 2-propanol as a promising fuel. The potential advantages of utilizing 2-propanol as fuel are many such as it is relatively less toxic compared to other alcohols, at low potentials it is less prone to anode poisoning, and it has better resistance to crossover and cathode poisoning. The performance of the fuel cell for a particular catalyst system is related to the cell conditions such as 2-propanol concentration, anode and cathode fuel flow rates, cell temperature and oxidant back pressure. This study was designed to study the effect of the different cell operation conditions at three different levels and the interactions between these components by response surface methodology (RSM). We observed that the power density of the cell increased with increase in molar concentration of 2-propanol and cell operation temperature, the optimized conditions for the highest power density of 45 mW/cm 2 by the RSM was found to be 1.5 M 2-propanol concentration, 80 o C cell temperature, 9.22 ml/min 2-propanol flow rate, 596 ml/min oxygen flow rate and no back pressure for the oxidant, this is from amongst one of the best results reported in literature for direct 2-propanol fuel cell performance.

Systems and Processes for Production of Fuel and Fuel Blends

Abstract: Systems and processes for the production of fuel and fuel blends involve the production of fuels for blending with one or more alcohols such as ethanol and/or butanol. A method for producing a fuel blend includes blending a light distillate product from an oil refinery with butanol. The fuel blending can be at the oil refinery.

Emission and performance characteristics of single cylinder diesel engine fuelled with neem biodiesel

Abstract: Energy shortage, soaring oil prices, and climate change stimulate the research and development of alternative energy resources to sustain economic growth. Biofuels, such as biodiesel and biomass-based alcohol fuels, are examples of such alternatives. The methyl esters of vegetable oils, known as biodiesel are becoming increasingly popular because of their low environmental impact and potential as a green alternative fuel for diesel engine and they would not require significant modification of existing engine hardware. Neem Methyl Esters (NME) are derived through transesterification process. Experimental investigations have been carried out to examine properties, performance and emissions of different blends (B10,B20,B30,B40,B50) of Neem methyl Esters in comparison to diesel. Results indicated that B30 and B50 have the closer performance to diesel. However, its diesel blends showed reasonable efficiencies, lower smoke, carbon monoxide, hydrocarbon and Nitrogen oxide.

Process for producing transportation fuels from syngas

Abstract: A process for producing transportation fuels, such as gasoline and diesel fuel, from syngas with a low H 2 /CO ratio. The syngas is first converted to dimethyl ether which is then converted to gasoline by way of a dimethyl ether to gasoline process and to diesel fuel by way of a Fischer-Tropsch process.

Life improvement programme of producer gas–biodiesel operated dual fuel engines

Abstract: Biomass fuels have attracted an increase in interest due to the alarming rise in global greenhouse gases and the rapid rise of petroleum prices. Energy security on a sustainable basis can come only with the responsible use of home-sourced resources and not from imported fossil fuels such as coal or crude petroleum products. Partial combustion of biomass in the downdraft gasifier generates producer gas that can be used as the sole fuel or as a supplementary fuel for internal combustion engines. A dual fuel mode of operation, in which producer gas is used as a supplementary inducted fuel along with injected pilot fuels of Honge or Jatropha biodiesels, can be a promising alternative to diesel only usage. Two different carburettors were designed and fabricated to facilitate gas entry at 45° and 90° to the engine cylinder. The engine was experimentally optimised using Honge or Jatropha biodiesels–producer gas combinations with respect to maximum pilot fuel savings in the dual fuel mode operation, optimum air a...

The Esterification of Jatropha Oil Using Different Short Chain Alcohols to Produce Esters to be Used as Biodiesel Fuel

Abstract: Esters of jatropha oil with short chain alcohols were prepared and evaluated as biodiesel fuel. The alcohols used include methyl, ethyl, propyl, and butyl alcohols. The volumetric ratio of alcohol to oil was 2:1 and the esterification was carried out at the boiling point of the used alcohol. Sulfuric acid was used as a catalyst at a concentration in the reaction mixture equivalent to 0.17 molar H+. The properties of the esters relevant to its use as a fuel, such as the calorific value, flash point, and viscosity, were compared to those of standard diesel fuel. The results have shown that the calorific value of the prepared esters were very close to that of standard diesel fuel. The flash points were higher than that of diesel fuel and it increases as the chain length of the alcohol increases. Also, the pour points were lower than standard diesel fuel.