Showing papers on "Alcohol fuel published in 2016"

Use of higher alcohol biofuels in diesel engines: A review

Abstract: Biofuels have grabbed the attention of engine researchers ever since the oil-crisis and escalating costs of petro-chemicals cropped up in the ׳70s. Ethanol and methanol were the most widely researched alcohols in IC engines. However, the last decade has witnessed significant amount of research in higher alcohols due to the development of modern fermentation processes using engineered micro-organisms that improved yield. Higher alcohols are attractive second/third generation biofuels that can be produced from sugary, starchy and ligno-cellulosic biomass feedstocks using sustainable pathways. The present work reviews the current literature concerning the effects of using higher alcohols ranging from 3-carbon propanol to 20-carbon phytol on combustion, performance and emission characteristics of a wide range of diesel engines under various test conditions. The literature is abound with evidence that higher alcohols reduce carcinogenic particulate emissions that are prevalent in diesel engines. NOx emissions either increased or decreased based on the domination of either cetane number or heat of evaporation. Brake specific fuel consumption (BSFC) of the engine usually suffered due to low energy content of alcohols. A notable feature is that the combination of higher alcohols (like butanol or pentanol), high exhaust gas recirculation (EGR) rates and late injection timing enabled low temperature combustion (LTC) in diesel engines that can simultaneously reduce smoke and NOx emissions with improved engine efficiency. It can be concluded that higher alcohols reduce smoke emissions with their fuel-borne oxygen; enhance air/fuel mixing by offering long ignition delay and eventually replace fossil diesel (partially or wholly) to enable a clean and efficient combustion in compression-ignition engines. The chief thrust areas include developing mutant strains with higher yield, higher tolerance to toxic inhibition and low-cost substrates for fermentation. Further work is required in stipulating optimum blend-fuel characteristics and ensuring the long-term durability of the engines using these fuels.

Pyrolytic Waste Plastic Oil and Its Diesel Blend: Fuel Characterization

Abstract: The authors introduced waste plastic pyrolysis oil (WPPO) as an alternative fuel characterized in detail and compared with conventional diesel. High density polyethylene, HDPE, was pyrolyzed in a self-designed stainless steel laboratory reactor to produce useful fuel products. HDPE waste was completely pyrolyzed at 330–490°C for 2-3 hours to obtain solid residue, liquid fuel oil, and flammable gaseous hydrocarbon products. Comparison of the fuel properties to the petrodiesel fuel standards ASTM D 975 and EN 590 revealed that the synthetic product was within all specifications. Notably, the fuel properties included a kinematic viscosity (40°C) of 1.98 cSt, density of 0.75 gm/cc, sulphur content of 0.25 (wt%), and carbon residue of 0.5 (wt%), and high calorific value represented significant enhancements over those of conventional petroleum diesel fuel.

Effect of emulsion fuel on engine emissions–A review

Abstract: Emulsion fuel is an unconventional fuel for diesel engines, which can be used without modifications in the engine. The benefits of an emulsion fuel include lowering the emissions of nitrogen oxides (NO x ) and particulate matter (PM) which are harmful to health and cause diesel engines to suffer. This paper explains in detail the effect of water in the emulsion fuel on the emissions of NO x , PM, carbon monoxide (CO), hydrocarbon (HC), smoke and exhaust temperature. Experimental results from various researchers show a decrease in the NO x and PM emissions simultaneously. However, the results with the increasing water percentage in emulsion fuel are not consistent for HC and CO emissions. The water content in emulsion fuel affects the combustion and reduces the peak temperature in the combustion chamber. On the other hand, microexplosion phenomenon occurs and causes an increase in the volatility of diesel fuel which improves the combustion efficiency.

Biobutanol as fuel for direct alcohol fuel cells - Investigation of Sn-modified Pt catalyst for butanol electro-oxidation

Abstract: Direct alcohol fuel cells (DAFCs) mostly use low molecular weight alcohols such as methanol and ethanol as fuels. However, short-chain alcohol molecules have a relative high membrane crossover rate in DAFCs and a low energy density. Long chain alcohols such as butanol have a higher energy density, as well as a lower membrane crossover rate compared to methanol and ethanol. Although a significant number of studies have been dedicated to low molecular weight alcohols in DAFCs, very few studies are available for longer chain alcohols such as butanol. A significant development in the production of biobutanol and its proposed application as an alternative fuel to gasoline in the past decade makes butanol an interesting candidate fuel for fuel cells. Different butanol isomers were compared in this study on various Pt and PtSn bimetallic catalysts for their electro-oxidation activities in acidic media. Clear distinctive behaviors were observed for each of the different butanol isomers using cyclic voltammetry (CV), indicating a difference in activity and the mechanism of oxidation. The voltammograms of both n-butanol and iso-butanol showed similar characteristic features, indicating a similar reaction mechanism, whereas 2-butanol showed completely different features; for example, it did not show any indication of poisoning. Ter-butanol was found to be inactive for oxidation on Pt. In situ FTIR and CV analysis showed that OHads was essential for the oxidation of primary butanol isomers which only forms at high potentials on Pt. In order to enhance the water oxidation and produce OHads at lower potentials, Pt was modified by the oxophilic metal Sn and the bimetallic PtSn was studied for the oxidation of butanol isomers. A significant enhancement in the oxidation of the 1° butanol isomers was observed on addition of Sn to the Pt, resulting in an oxidation peak at a potential ∼520 mV lower than that found on pure Pt. The higher activity of PtSn was attributed to the bifunctional mechanism on PtSn catalyst. The positive influence of Sn was also confirmed in the PtSn nanoparticle catalyst prepared by the modification of commercial Pt/C nanoparticle and a higher activity was observed for PtSn (3:1) composition. The temperature-dependent data showed that the activation energy for butanol oxidation reaction over PtSn/C is lower than that over Pt/C.

Exhaust PM Emissions Analysis of Alcohol Fueled Heavy-Duty Engine Utilizing PPC

Abstract: The focus has recently been directed towards the engine out soot from Diesel engines. Running an engine in PPC (Partially Premixed Combustion) mode has a proven tendency of reducing these emissions significantly. In addition to combustion strategy, several studies have suggested that using alcohol fuels aid in reducing soot emissions to ultra-low levels. This study analyzes and compares the characteristics of PM emissions from naphtha gasoline PPC, ethanol PPC, methanol PPC and methanol diffusion combustion in terms of soot mass concentration, number concentration and particle size distribution in a single cylinder Scania D13 engine, while varying the intake O2. Intake temperature and injection pressure sweeps were also conducted. The fuels emitting the highest mass concentration of particles (Micro Soot Sensor) were gasoline and methanol followed by ethanol. The two alcohols tested emitted nucleation mode particles only, whereas gasoline emitted accumulation mode particles as well. Regarding soot mass concentration measurements; methanol never exceeded 1.6 mg/m3 while when operating on gasoline this value never descended below 1.6 mg/m3. From this result it can be concluded that the main contributor to PM mass emissions is mainly increasing CMD (Count Mean Diameter) in the accumulation mode size range, but can in diffusion combustion also be caused by a high amount of nucleation mode particles. A probable cause of higher particle number emissions, when running the engine on methanol compared to ethanol, is the corrosiveness of the fuel itself. Except for the ultra-low PM mass emitted from alcohol combustion, it is also possible to alter the EGR concentration with a higher level of freedom without having to consider the NOX - soot tradeoff.

Low-Carbon Aviation Fuel Through the Alcohol to Jet Pathway

Abstract: The aviation industry is seeking economical and technically viable approaches to providing sustainable alternatives to petroleum-based jet fuel. For example, the Federal Aviation Administration (FAA) Destination 2025 (FAA 2025) has a goal to develop cleaner jet fuels, explore new ways to meet environmental and energy goals, and foster development towards one billion gallons of renewable jet fuel for aviation use by 2018. Alternative jet fuels via Fischer–Tropsch (F–T) and hydrotreated vegetable oils (HEFA) have already been approved for use in jet fuel blends of up to 50%. Other conversion processes, such as alcohol to jet (ATJ), are in various stages of development. This chapter focuses on opportunities for production of jet fuel blend components through an ethanol intermediate via a number of processing routes. These are then compared to conversion routes through other oxygenated intermediates, such as higher alcohols (eg, butanol). Higher alcohols provide technically simple conversion chemistry routes to jet blend components, but are currently produced in small quantities (relative to fuels) for the chemical market. Ethanol on the other hand is widely produced as both a fuel and a chemical and has an established distribution infrastructure. Furthermore, renewable ethanol volumetric yields via fermentation surpass those of higher alcohols. Ethanol conversion processes can produce both paraffinic and cyclic molecules. However, the conversion pathway from ethanol through ethylene is more challenging than from higher alcohol-derived olefins. Mixed oxygenated intermediates can also belong in the ATJ category, but are not yet at the same stage of development as alcohols. The major market drivers for producing alternative jet fuel components, including ATJ, are climate change, cost stability, and national security. Biologically derived ATJ fuels can provide significant climate change benefits by reducing CO2 life cycle emissions, possibly exceeding 80%. In addition, they produce lower levels of sulphur oxides and particulate matter. Because jet fuel accounts for 40% of an airline’s operating costs, reducing price fluctuations associated with petroleum is another significant driver. Finally, dependence on foreign oil could be minimized using alternative fuels. As a result of these drivers, government agencies as well as the private sector have set aggressive targets to increase their consumption of alternative fuels. In addition to targets, the government has provided favourable policies to incentivize alternative aviation fuel use. Carbon taxes abroad and potentially in the United States will drive up prices of petroleum-based fuels, making alternative fuels more competitive. Government incentives in the form of renewable fuel credits are expected to further improve alternative fuel viability. Energy Information Agency (EIA) projections suggest there may be a significant surplus of ethanol over that required for gasoline blending, potentially filling 4% of jet fuel demand in 2020. EIA projections also suggest there is a positive price differential between ethanol intermediate and jet fuel in future scenario projections, unless oil prices drop to the Low Oil Case. Ethanol currently has a price and market share advantage over other alcohols, such as butanol. However, development of ethanol to jet technology lags butanol to jet technology. Reported production costs for raw ethanol, projected ethanol supplies over that needed for gasoline blending, and the presence of existing infrastructure all suggest that ethanol is a viable intermediate for the production of alternative jet fuel components.

Critical factors affecting the integration of biomass gasification and syngas fermentation technology

Abstract: Gasification-fermentation is a thermochemical-biological platform for the production of fuels and chemicals. Biomass is gasified at high temperatures to make syngas, a gas composed of CO, CO2, H2, N2 and other minor components. Syngas is then fed to anaerobic microorganisms that convert CO, CO2 and H2 to alcohols by fermentation. This platform offers numerous advantages such as flexibility of feedstock and syngas composition and lower operating temperature and pressure compared to other catalytic syngas conversion processes. In comparison to hydrolysis-fermentation, gasification-fermentation has a major advantage of utilizing all organic components of biomass, including lignin, to yield higher fuel production. Furthermore, syngas fermentation microorganisms do not require strict CO:H2:CO2 ratios, hence gas reforming is not required. However, several issues must be addressed for successful deployment of gasification-fermentation, particularly those that involve the integration of gasification and fermentation. Most previous reviews have focused only on either biomass gasification or syngas fermentation. In this review, the critical factors that affect the integration of biomass gasification with syngas fermentation, such as carbon conversion efficiency, effect of trace gaseous species, H2 to CO ratio requirements, and microbial preference of carbon substrate, are thoroughly discussed.

Assessment of thermodynamic performance and exergetic sustainability of turboprop engine using mixture of kerosene and methanol

Abstract: In this study, first and second laws of thermodynamics were performed in the turboprop and is analysed and discussed with the mathematical model of sustainability performance of a turboprop engine using a mixture of alternative fuel (Methanol CH3OH) and conventional fuel (Kerosene C12H26). The results showed when the excess air is kept constant, with the increases of the alternative fuel, mixture is enriched with oxygen as a source of methanol and the actual air-fuel ratio decreased was determined. When the rate of alternative fuel in mixture was increased, it was observed that the fuel flow started to increase, because Lower Heating Value of methanol is lower than kerosene. Therefore, increasing of fuel consumption was found to obtain the same power in propeller as negative effect. ESIs - waste exergy ratio, exergy destruction factor and environmental effect factor - is increased with the increasing ratio of methanol in the mixture.

Ternary PtRuPd/C Catalyst for High‐Performance, Low‐Temperature Direct Dimethyl Ether Fuel Cells

Abstract: Here, dimethyl ether (DME) is a promising alternative fuel option for direct-feed low-temperature fuel cells. Until recently, DME had not received the same attention as alcohol fuels, such as methanol or ethanol, despite its notable advantages. These advantages include a high theoretical open-cell voltage (1.18 V at 25 °C) that is similar to that of methanol (1.21 V), much lower toxicity than methanol, and no need for the carbon–carbon bond scission that is needed in ethanol oxidation. DME is biodegradable, has a higher energy content than methanol (8.2 vs. 6.1 kWh kg–1), and, like methanol, can be synthesized from recycled carbon dioxide. Although the performance of direct DME fuel cells (DDMEFCs) has progressed over the past few years, DDMEFCs have not been viewed as fully viable. In this work, we report much improved performance from the ternary Pt55Ru35Pd10/C anode catalyst, allowing DDMEFCs to compete directly with direct methanol fuel cells (DMFCs). We also report results involving binary Pt alloys as reference catalysts and an in situ infrared electrochemical study to better understand the mechanism of DME electro-oxidation on ternary PtRuPd/C catalysts.

Effects of Substitution on Counterflow Ignition and Extinction of C3 and C4 Alcohols

Abstract: Dwindling reserves and inherent uncertainty in the price of conventional fuels necessitates a search for alternative fuels. Alcohols represent a potential source of energy for the future. The structural features of an alcohol fuel have a direct impact on combustion properties. In particular, substitution in alcohols can alter the global combustion reactivity. In this study, experiments and numerical simulations were conducted to investigate the critical conditions of extinction and autoignition of n-propanol, 1-butanol, iso-propanol, and iso-butanol in nonpremixed diffusion flames. Experiments were carried out in the counterflow configuration, while simulations were conducted using a skeletal chemical kinetic model for the C3 and C4 alcohols. The fuel stream consists of the prevaporized fuel diluted with nitrogen, while the oxidizer stream is air. The experimental results show that autoignition temperatures of the tested alcohols increase in the following order: iso-propanol > iso-butanol > 1-butanol ≈ n-...

Effect of Diesel–Water Emulsified Fuel on the NOx and PM Emissions of a Diesel Engine

Abstract: With increasing concern over global warming and energy consumption, diesel engines have received considerable attention due to their high thermal efficiency. However, diesel engines still suffer from high NOx and PM emissions. Therefore, this study focuses on the use of diesel–water emulsified (DE) fuel to reduce NOx and PM emissions and evaluates its application to conventional diesel engines based on the fundamental characteristics of DE fuel. DE fuels were applied to actual diesel engines, and their combustion, emission, and fuel consumption characteristics were compared with those of diesel fuel. The injection time was the same in all experiments. The coefficient of variation (COV) of all DE fuels was stable at a value as low as 2.0%, and the combustion duration was shorter than that of diesel fuel. The NOx and PM generation rates of DE fuels were considerably lower than those of diesel fuel because of the beneficial effects of the microexplosion and evaporative latent heat.

The effects of additives on the reduction of the pour point of diesel fuel and fuel oil

Abstract: One important industrial problem is the wax precipitation of oil fractions. Factors such as oil composition, temperature, and pressure are effective in causing wax precipitation. One way to prevent...

Effects of ethanol on combustion and emissions of a gasoline engine operating with different combustion modes

Abstract: The introduction of fuel economy and CO2 emission legislations for passenger cars in many countries and regions has spurred the research and development of more efficient gasoline engines. The pump...

Combustion and Emissions in an HSDI Engine Running on Diesel or Vegetable Oil Base Fuel with n-Butanol or Diethyl Ether As a Fuel Extender

Abstract: The present investigation compares the combustion, performance, and exhaust emissions of diesel fuel in blends with either 24% n-butanol or 24% diethyl ether (DEE), and of vegetable (cottonseed) oil in blends with either 20% n-butanol or 20% diethyl ether, fueling a standard, experimental, single-cylinder, four-stroke, high-speed direct injection (HSDI), Hydra diesel engine operated at three different loads. Fuel consumption, and exhaust smoke, nitrogen oxides (NOx), carbon monoxide (CO), and total unburned hydrocarbons (HC) were measured. The differences in combustion, performance, and exhaust emissions of those biofuel blends are compared from the baseline operations, i.e., when working with the neat base fuels (diesel fuel or vegetable oil). Fuel injection, combustion chamber pressure, heat release rate, and temperature diagrams, reveal interesting features of the combustion mechanisms. These results and the differing physical and chemical properties of those biofuels are used to aid the interp...

Enhancing Fuel Efficiency and Environmental Specifications of a Marine Diesel When using Fuel Additives

Abstract: Objectives: The article is aimed at discussing the results of application of marine motor fuel additives. Method: A method for improving fuel performance properties by applying fuel additives has been proposed. A 6N21L medium-speed fourstroke cycle diesel by Yanmar was used for this research. A RME25 marine fuel, viscosity of 25 sSt at 100oC and sulphur content of 2.8 w.w%, was applied. An additive containing active oxygen-bearing groups and modified with light metal salts was used as a fuel additive. Findings: Experiments were done, using three diesels of the same type, which allowed for one diesel to run on the basic fuel, and for feeding the additive-containing fuel into cylinders of two other diesels (following additional equipment of the fuel system with a flow meter and a dispenser). Specific fuel oil consumption, exit gas temperature, NOx and SOx concentration in the exit gases, and technical condition of fuel system and cylinderpiston group elements were determined in this experiment. It was shown that the use of fuel additives improves fuel efficiency of a marine diesel, in particular reduces specific fuel oil consumption by 3.5 to 5.8% subject to diesel load and additive concentration in the fuel. Improved environmental performance of the diesel, i.e. NOx reduction by 1.4 to 4.3% and SOx reduction by 15.6 to 22.9% in exit gases, was also found. It was shown that additive concentration is of optimal importance, can be determined experimentally and depends on diesel and fuel specification. Improvements: Improved technical condition of diesel cylinder-piston group and gas outlet system elements was determined as a result of visual inspection, thus reducing work labor input for diesel purging by 20 to 25%.

High-content environmental alcohol ether fuel used for compression ignition engine

Abstract: The invention discloses a high-content environmental alcohol ether fuel used for a compression ignition engine, which belongs to the technical field of alcohol ether fuel clean energy. The alcohol ether fuel comprises the following raw materials: methanol or ethanol or a mixture of methanol and ethanol, toluene, stearic acid, hexamethylphosphoric triamide, a nitryl solvent, acetone, fatty acid methyl ester, n-alkane, N-toluidine, plant oil, an alcohol fuel ether stabilizing agent, a catalysis combustion-supporting agent, an anti-knock reinforcing agent, a cetane number regulator, an eduction agent, an alcohol fuel recognition agent, an alcohol fuel rubber/plastic part corrosion and swelling inhibitor, an alcohol fuel metal corrosion inhibitor, an antioxidant anti-gum inhibitor, a metal deactivator, a corrosion inhibitor, an antistatic agent, a purification dispersant, an anti-wear repair agent, and an alcohol fuel sterilizing agent. The high-content environmental alcohol ether fuel has the advantages of stable performance, strong power, full combustion, good anti-knock property, good acceleration speed, easy starting, no air resistance, and low fuel consumption, and is especially suitable for the compression ignition engine.