Ethanol-gasoline Blends Research Articles

Experimental study on the influence of ethanol and automotive gasoline blends

Experimental study on the influence of ethanol and automotive gasoline blends

Atmospheric ethanol in London and the potential impacts of future fuel formulations.

There is growing global consumption of non-fossil fuels such as ethanol made from renewable biomass. Previous studies have shown that one of the main air quality disadvantages of using ethanol blended fuels is a significant increase in the production of acetaldehyde, an unregulated and toxic pollutant. Most studies on the impacts of ethanol blended gasoline have been carried out in the US and Brazil, with much less focus on the UK and Europe. We report time resolved measurements of ethanol in London during the winter and summer of 2012. In both seasons the mean mixing ratio of ethanol was around 5 ppb, with maximum values over 30 ppb, making ethanol currently the most abundant VOC in London air. We identify a road transport related source, with 'rush-hour' peaks observed. Ethanol is strongly correlated with other road transport-related emissions, such as small aromatics and light alkanes, and has no relationship to summer biogenic emissions. To determine the impact of road transport-related ethanol emission on secondary species (i.e. acetaldehyde and ozone), we use both a chemically detailed box model (incorporating the Master Chemical Mechanism, MCM) and a global and nested regional scale chemical transport model (GEOS-Chem), on various processing time scales. Using the MCM model, only 16% of the modelled acetaldehyde was formed from ethanol oxidation. However, the model significantly underpredicts the total levels of acetaldehyde, indicating a missing primary emission source, that appears to be traffic-related. Further support for a primary emission source comes from the regional scale model simulations, where the observed concentrations of ethanol and acetaldehyde can only be reconciled with the inclusion of large primary emissions. Although only constrained by one set of observations, the regional modelling suggests a European ethanol source similar in magnitude to that of ethane (∼60 Gg per year) and greater than that of acetaldehyde (∼10 Gg per year). The increased concentrations of ethanol and acetaldehyde from primary emissions impacts both radical and NOx cycling over Europe, resulting in significant regional impacts on NOy speciation and O3 concentrations, with potential changes to human exposure to air pollutants.

Compliance Path and Impact of Ethanol Mandates on Retail Fuel Market in the Short Run

Past studies have examined the impact of ethanol mandates with a long‐run perspective and were thus able to assume away short‐run rigidities and some of the specifics of the biofuel mandates. These studies have been of limited use in informing current policy debates because the short‐ to medium‐run reality is one of strong regulatory and infrastructure rigidities that restrict how ethanol can be consumed in the United States. Our objectives in this paper are to provide a more coherent framework than currently exists to model and understand how compliance with ethanol mandates in the short run cannot be met with conventional gasoline blends, how compliance impacts fuel prices and consumer and producer welfare, and also to measure the size of the transfer that occurs between refineries and ethanol producers through the market's Renewable Identification Numbers (RINs). In a model calibrated to 2015 data, we find that the effects of increasing ethanol mandates that are physically feasible are close to zero on the retail price of gasoline. This result is robust to different gasoline prices, supply elasticities, and export‐demand elasticities. Increased mandates can have a large negative effect on the price of high‐level ethanol gasoline blends such as E85 if the mandates are increased to approach consumption capacity.

POWER PERFORMANCE AND FUEL CONSUMPTION OF A SPARK IGNITION ENGINE USING DIFFERENT BLENDS OF ETHANOL GASOLINE

The Philippine Government Alternative Fuel Program now mandates a 10% bioethanol blend for commercial gasolines sold at the pumps. Numerous laboratory studies of different kinds of bioethanol in different countries exist but none yet in the Philippines, specifically, in vehicle use. A research was conduct ed at the UPME Vehicle Research and Testing Laboratory (VRTL) to investigate experimentally the effects on engine’s power performance and specific fuel consumption (SFC) of E5 (5% ethanol), E10 (10%), E12.5 (12.5%), E15 (15%), E20 (20%), E25 (25%) and E30 (30%) ethanol gasoline blends by volume as compared to neat gasoline (E0). The vehicle was driven in road load simulation at standard Japanese drivingcycle while measuring fuel consumption and power developed. Each blend test passed three trials using the AVL Chassis Dynamometer equipped with fuel mass flow meter with temperature control. Test showed positive correlation between mass specific fuel consumption (MSFC) and ethanol amount in the fuel mixture. From 44.68 g/km at E0, it raised continuously to 45 .58g/km(E5), 45.79g/km(E10), 45.89g/km(E12.5), 46.11g/km(E15), 46.33g/km(E20), 46.71(E25) and 49.14g/km(E30). Lower energy content of ethanol gasoline fuel caused an increase in the engine’s MCSF or a decrease in mileage in all blended fuels. However, the energy specific fuel consumption (ESFC) gives a better picture of the efficiency on fuel conversion. There was an improved maximum power obtained for E5, E12.5, E20 and E25 of about 1.9%, 0.55%, 1.64% and 3.4% respectively, while E10 and E15 decreased in o utputs by 0.78% and 0.32% respectively. These blends show relatively comparable output to neat gasoline due to oxygen content of ethanol outweighing lower heating value. E30 showed the biggest reduction at 3.43% lower than neat gasoline. In general, during the experiment, no significant problem was encountered in the engine performance. This means that all blends tested were suitable to the vehicle

SVM and ANFIS for prediction of performance and exhaust emissions of a SI engine with gasoline–ethanol blended fuels

This paper studies the use of support vector machine (SVM) and adaptive neuro-fuzzy inference system (ANFIS) to predict the performance parameters and the exhaust emissions of a spark ignition (SI) engine, which operates on ethanol–gasoline blends of 0%, 5%, 10%, 15% and 20% called E0, E5, E10, E15 and E20, respectively. In the experiments, the engine was run at various speeds for each test fuel, and 45 different test conditions were created. In comparison with gasoline fuel, the brake power, the engine torque, the brake thermal efficiency, and the volumetric efficiency increased using ethanol blends, while the brake specific fuel consumption (bsfc) decreased. Moreover, the concentration of CO and HC in the exhaust pipe decreased after ethanol blends were introduced, but CO2 and NOX emissions increased. In order to predict the engine parameters, all the experimental data were randomly divided into training and testing data. For SVM modelling, different values for the radial basis function (RBF) kernel width and the penalty parameters (C) were considered, and the optimum values were then found. For ANFIS modelling, the Gaussian curve membership function (gaussmf) and 200 training epochs were found to be the optimum choices for the training process. The results showed that the SVM predicted the engine performance and the exhaust emissions with the correlation coefficient (R) and the accuracy in the ranges of 0.660–1 and 65.310–99.330%, respectively, while these same parameters were in the ranges of 0.760–1 and 79.270–98.810%, respectively, for the ANFIS. The results demonstrate that the SVM and ANFIS are capable of predicting the SI engine performance and emissions. However, the performance of the ANFIS is significantly higher than that of the SVM.

Physical properties of gasoline, isobutanol and ETBE binary blends in comparison with gasoline ethanol blends

The addition of renewable fuels to gasoline, such as bio-alcohols or bio-ethers is required in order to be in compliance with current environmental directives. Nevertheless, they change fuel properties which could affect standards compliance, engine performance and air emissions. This paper studies the impact of ethanol (EtOH), isobutanol (iBtOH) or ethyl tert-butyl ether (ETBE) on the Reid Vapour Pressure (RVP), distillation curves, density and other related gasoline properties, which belong to the group of relevant specifications that affect engine operation. The main conclusion is that the addition of ETBE or iBtOH has important advantages over EtOH in terms of energy density, air/fuel ratio, vapour pressure, renewable content and other effects; it was also found that the addition of ETBE affects equally and linearly the properties of two kinds of base gasolines as compared with other studies.

EFFECTS OF ETHANOL BLENDS ON GASOLINE ENGINE PERFORMANCE AND EXHAUST EMISSIONS

Automotive sector is one of the major contributors to air pollution and global warming due to the carbon residue and smoke opacity emission. Today, the trend of decreasing sources of petroleum fuel has led to innovation of other resources such as alternative fuel. Alternative fuel can be produced from biomass such as alcohol in which it is produced by fermentation of sugar, cane and corn. This experiment was conducted to investigate the effects of ethanol on gasoline engine performance and exhaust emissions. A four-stroke, single cylinder engine was tested by different range of ethanol volume percentages i.e. 10% (E10), 20% (E20) and 30% (E30) blended with fossil gasoline. The experiment was carried out at variations of engine speed and constant load. The engine speeds used for a constant load at 2 Nm were 2000rpm, 2500rpm and 3000rpm. From the results obtained, it shows that the brake specific fuel consumption for the blended fuel is better than gasoline fuel. Combustion efficiency of gasoline engine has improved with the use of ethanol-gasoline blends. Exhaust emissions such as CO and smoke opacity are decreased due to the presence of oxygenated properties of ethanol in blended fuel. However, emissions of CO2 are increased due to the high combustion temperature. In overall, the E20 shows the best results for all measured parameters at all engine test conditions.

Nitrogen rate and landscape impacts on life cycle energy use and emissions from switchgrass‐derived ethanol

AbstractSwitchgrass‐derived ethanol has been proposed as an alternative to fossil fuels to improve sustainability of the US energy sector. In this study, life cycle analysis (LCA) was used to estimate the environmental benefits of this fuel. To better define the LCA environmental impacts associated with fertilization rates and farm‐landscape topography, results from a controlled experiment were analyzed. Data from switchgrass plots planted in 2008, consistently managed with three nitrogen rates (0, 56, and 112 kg N ha−1), two landscape positions (shoulder and footslope), and harvested annually (starting in 2009, the year after planting) through 2014 were used as input into the Greenhouse gases, Regulated Emissions and Energy use in transportation (GREET) model. Simulations determined nitrogen (N) rate and landscape impacts on the life cycle energy and emissions from switchgrass ethanol used in a passenger car as ethanol–gasoline blends (10% ethanol:E10, 85% ethanol:E85s). Results indicated that E85s may lead to lower fossil fuels use (58 to 77%), greenhouse gas (GHG) emissions (33 to 82%), and particulate matter (PM2.5) emissions (15 to 54%) in comparison with gasoline. However, volatile organic compounds (VOCs) and other criteria pollutants such as nitrogen oxides (NOx), particulate matter (PM10), and sulfur dioxides (SOx) were higher for E85s than those from gasoline. Nitrogen rate above 56 kg N ha−1 yielded no increased biomass production benefits; but did increase (up to twofold) GHG, VOCs, and criteria pollutants. Lower blend (E10) results were closely similar to those from gasoline. The landscape topography also influenced life cycle impacts. Biomass grown at the footslope of fertilized plots led to higher switchgrass biomass yield, lower GHG, VOCs, and criteria pollutants in comparison with those at the shoulder position. Results also showed that replacing switchgrass before maximum stand life (10–20 years.) can further reduce the energy and emissions reduction benefits.

Performance Evaluation of SI (Spark Ignition) Engine using Ethanol Gasoline Blend at Various Compression Ratio

Performance Evaluation of SI (Spark Ignition) Engine using Ethanol Gasoline Blend at Various Compression Ratio

Impact of intermediate ethanol blends on particulate matter emission from a spark ignition direct injection (SIDI) engine

The purpose of this study was to investigate particle emission characteristics from a spark ignition direct injection (SIDI) engine fueled with ethanol–gasoline blends. Particulate matter (PM) from internal combustion engine is a complex mixture of substances deemed harmful for the human body. Consequently, they are regulated by stringent legislation. According to the Euro-6 regulation, the standard for particle number (PN) emissions of SIDI vehicles is 6.0×1011N/km. Recent studies have reported that SIDI engines, renowned for their feasibility in reducing CO2 emissions, could produce excessive amounts of PM due to its structural characteristics. For this reason, there have been many studies on reducing PM emissions from SIDI engines to satisfy strict emission standards. Because ethanol contains an oxygen atom in each molecule, it has a significant influence on combustion performance and characteristics of vehicular discharge, including PM. This study focused on the effect of intermediate ethanol blends from E0 (pure gasoline fuel) to E20 (gasoline fuel with 20% volume of ethanol) on engine performance, size-resolved particle emissions, and engine startability. Particle emission characteristics including particle number and size distribution at part-load test and start performance were investigated with operation points, fuel pressure and injection timing.

Optimization of performance and exhaust emission parameters of a SI (spark ignition) engine with gasoline–ethanol blended fuels using response surface methodology

This paper studies the use of RSM (response surface methodology) to optimize the performance parameters and exhaust emissions of a SI (spark ignition) engine which operates with ethanol–gasoline blends of 5%, 7.5%, 10%, 12.5% and 15% called E5, E7.5, E10, E12.5 and E15. In the experiments, the engine ran at various speeds for each test fuel and 45 different conditions were constructed. In comparison with gasoline fuel, the brake power, engine torque, increased using ethanol blends, and the bsfc (brake specific fuel consumption) decreased as well. Moreover, the concentration of CO and HC in the exhaust pipe decreased by introducing ethanol blends, but CO2 and NOx emissions increased. Optimization of independent variables was performed using the desirability approach of the RSM (response surface methodology) with the goal of minimizing emissions and maximizing of performance parameters. The experiments were designed using a statistical tool known as DoE (design of experiments) based on RSM. Engine-operating parameters were optimized using the Desirability approach of RSM. The performance parameters for different biofuel–gasoline blends were found close to gasoline, and emission characteristics of the engine improved significantly. An engine speed of 3000 rpm and a blend of 10% bioethanol and 90% gasoline (E10) were found to be optimal values. The results of this study revealed that at optimal input parameters, the values of the brake power, Torque, bsfc, and CO, CO2, HC, NOx were found to be 35.26 (kW), 103.66 (Nm), 0.25 (kg/kW hr), 3.5 (%Vol.), 12.8 (%Vol.), 136.6 (ppm) and 1300 (ppm) respectively.

Experimental Investigation of S.I. Engine on Gasoline and Ethanol-Gasoline Blend for Engine Performance Characteristics

Experimental Investigation of S.I. Engine on Gasoline and Ethanol-Gasoline Blend for Engine Performance Characteristics

Investigations on the effects of ethanol–methanol–gasoline blends in a spark-ignition engine: Performance and emissions analysis

This study discusses performance and exhaust emissions from spark-ignition engine fueled with ethanol–methanol–gasoline blends. The test results obtained with the use of low content rates of ethanol–methanol blends (3–10 vol.%) in gasoline were compared to ethanol–gasoline blends, methanol–gasoline blends and pure gasoline test results. Combustion and emission characteristics of ethanol, methanol and gasoline and their blends were evaluated. Results showed that when the vehicle was fueled with ethanol–methanol–gasoline blends, the concentrations of CO and UHC (unburnt hydrocarbons) emissions were significantly decreased, compared to the neat gasoline. Methanol–gasoline blends presented the lowest emissions of CO and UHC among all test fuels. Ethanol–gasoline blends showed a moderate emission level between the neat gasoline and ethanol–methanol–gasoline blends, e.g., ethanol–gasoline blends presented lower CO and UHC emissions than those of the neat gasoline but higher emissions than those of the ethanol–methanol–gasoline blends. In addition, the CO and UHC decreased and CO2 increased when ethanol and/or methanol contents increased in the fuel blends. Furthermore, the effects of blended fuels on engine performance were investigated and results showed that methanol–gasoline blends presents the highest volumetric efficiency and torque; ethanol–gasoline blends provides the highest brake power, while ethanol–methanol–gasoline blends showed a moderate level of volumetric efficiency, torque and brake power between both methanol–gasoline and ethanol–gasoline blends; gasoline, on the other hand, showed the lowest volumetric efficiency, torque and brake power among all test fuels.

Fuel consumption and emissions from a vehicle operating with ethanol, gasoline and hydrogen produced on-board

This paper investigates fuel consumption and pollutant emissions from a vehicle operating with gasoline-ethanol blend (E22), hydrous ethanol (E100) and hydrogen produced on-board. The study aims to find out if hydrogen can contribute to reduce fuel consumption and emissions. Hydrogen was produced by a hydrolytic cell adapted to the vehicle, and was mixed to the air charge in the intake pipe. A production automobile powered by a 1.0-L flexible fuel engine was used in the tests. The vehicle was tested on a chassis dynamometer, with the engine operating at idle speed and at 1400 rev/min. The results show that small amounts of hydrogen can provide stable engine operation with lean fuel-air mixture and, thus, reduce fuel consumption without compromising exhaust emission levels. Reductions of up to 11.8% and 13.1% on fuel consumption were obtained for E22 and E100, respectively.

Effect of Ethanol Ratio on Ignition and Combustion of Ethanol-Gasoline Blend Spray in DISI Engine-Like Condition

Effect of Ethanol Ratio on Ignition and Combustion of Ethanol-Gasoline Blend Spray in DISI Engine-Like Condition

Prenatal exposure to vapors of gasoline–ethanol blends causes few cognitive deficits in adult rats

Developmental exposure to inhaled ethanol–gasoline fuel blends is a potential public health concern. Here we assessed cognitive functions in adult offspring of pregnant rats that were exposed to vapors of gasoline blended with a range of ethanol concentrations, including gasoline alone (E0) and gasoline with 15% or 85% ethanol (E15 and E85, respectively). Rat dams were exposed for 6.5h daily to the vapors at concentrations of 0, 3000, 6000, or 9000ppm in inhalation chambers from gestational day (GD) 9 through 20. Cage controls (offspring of non-exposed dams that remained in the animal facility during these exposures) were also assessed in the E0 experiment, but showed no consistent differences from the offspring of air-exposed controls. Offspring were tested as adults with trace fear conditioning, Morris water maze, or appetitive operant responding. With fear conditioning, no significant effects were observed on cue or context learning. In the water maze, there were no differences in place learning or escaping to a visible platform. However, during the reference memory probe (no platform) male rats exposed prenatally to E85 vapor (6000 and 9000ppm) failed to show a bias for the target quadrant. Across studies, females (treated and some controls) were less consistent in this measure. Males showed no differences during match-to-place learning (platform moved each day) in any experiment and females showed only transient differences in latency and path length in the E0 experiment. Similarly, no differences were observed in delayed match-to-sample operant performance of E0 males or females; thus this test was not used to evaluate effects of E15 or E85 vapors. During choice reaction time assessments (only males were tested) decision and movement times were unimpaired by any prenatal exposure, while anticipatory responses were increased by vapors of E0 (9000ppm) and E15 (6000 and 9000ppm), and the latter group also showed reduced accuracy. E85 vapors did not disrupt any choice reaction time measure. Finally, no response inhibition deficit was observed in a differential reinforcement of low rate (DRL) response schedule in males or females in the E15 or E85 experiments. In summary, prenatal exposure to these fuel blends produced few deficits in adult offspring on these cognitive tests. Significant effects found during a water maze probe trial and choice reaction time tests were observed at vapor concentrations of 6000ppm or higher, a concentration that is 4–6 orders of magnitude higher than those associated with normal automotive fueling operations and garages. Similar effects were not consistently observed in a previous study of inhaled ethanol, and thus these effects cannot be attributed to the concentration of ethanol in the mixture.

Multi-objective regulations on transportation fuels: Comparing renewable fuel mandates and emission standards

We compare two types of fuel market regulations — a renewable fuel mandate and a fuel emission standard — that could be employed to simultaneously achieve multiple outcomes such as reduction in fuel prices, fuel imports and greenhouse gas (GHG) emissions. We compare these two types of regulations in a global context taking into account heterogeneity in carbon content of both fossil fuels and renewable fuels. We find that although neither the ethanol mandate nor the emission standard is certain to reduce emissions relative to a business-as-usual baseline, at any given level of biofuel consumption in the policy region, a mandate, relative to an emission standard, results in higher GHG emissions, smaller expenditure on fuel imports, lower price of ethanol-blended gasoline and higher domestic fuel market surplus. This result holds over a wide range of values of model parameters. We also discuss the implications of this result to a regulation such as the US Renewable Fuel Standard given recent developments within the US such as increase in shale and tight oil production and large increase in average vehicle fuel economy of the automotive fleet.

Comparative Study of Performance of Four-Stroke Two Wheeler using Ethanol-Gasoline and Butanol Gasoline Blends

Comparative Study of Performance of Four-Stroke Two Wheeler using Ethanol-Gasoline and Butanol Gasoline Blends

Particle speciation of emissions from iso-butanol and ethanol blended gasoline in light-duty vehicles

Vehicular emissions of Particulate Matter (PM) will change under different driving conditions and as higher levels of alternative fuels are blended with gasoline. In particular, the chemical composition and water-soluble components of PM below 2.5μm can be modified. In this study, three light-duty Port-Fuel Injection (PFI) and two Gasoline Direct Injection (GDI) vehicles were tested. All vehicles were tested over the Federal Test Procedure (FTP), Unified Cycle (UC), and at steady-state speeds (30, 50, and 70mph) while operating on various ethanol and iso-butanol gasoline blends. The chemical and physical properties of the aerosol composition were measured via online/offline methods. Black carbon (BC), water-soluble organic carbon (WSOC), and droplet surface tension were measured. Water-Insoluble Mass (WIM) fractions were estimated from online size distribution measurements. Results show that the PFI vehicles, fuel composition and testing conditions (transient versus steady-state) impact PM emissions. GDI vehicles emit more PM and twice as much BC compared to PFI vehicles. Older PFI vehicles also produce more particles and BC emissions than newer vehicles. For three of the five vehicles, as speed increased, the WIM fraction increased. The results show vehicle operating conditions (steady-state or transient) can greatly impact the average composition of particles regardless of fuel composition.

Comparison of combustion characteristics of n-butanol/ethanol–gasoline blends in a HCCI engine

As a sustainable biofuel, n-butanol can be used in conventional spark ignition (SI) and compression ignition (CI) engines in order to reduce the dependence on fossil fuel. Homogeneous charge compression ignition (HCCI) is a novel combustion to improve the thermal efficiency of conventional SI engines at part loads. To understand the effect of alcohol structure on HCCI combustion under stoichiometric conditions highly diluted by exhaust gases, the combustion characteristics of n-butanol, ethanol and their blends with gasoline were investigated on a single cylinder port fuel injection gasoline engine with fixed intake/exhaust valve lifts at the same operating conditions in this study. The results show that autoignition timing for alcohol–gasoline blends is dependent on alcohol types and its concentration in the blend, engine speed and intake valve opening (IVO)/exhaust valve closing (EVC) timing. In the operating conditions with the residual gases more than 38% by mass in the mixture, alcohol–gasoline blends autoignite more easily than gasoline. Autoignition timing for n-butanol–gasoline blend is earlier than that for ethanol–gasoline blend with the same alcohol volume fraction at 1500rpm in most cases while the autoignition timings for the blends with alcohol are relatively close at 2000rpm at the same IVO/EVC timing. Combustion stability is improved with advanced EVC timing at a fixed IVO timing, which is benefit for the improvement in the thermal efficiency in the case of alcohol–gasoline blends. In addition, n-butanol–gasoline blends autoignite earlier than their ethanol–gasoline counterparts with identical oxygen mass content in the blend at the same IVO/EVC timings regardless of engine speeds. For alcohol–gasoline blends, the effect of IVO/EVC timing on the thermal efficiency of the HCCI engine is dependent on autoignition timing, fuel types and engine speeds. However, advanced autoignition timing for the blends with alcohol worsens the thermal efficiency of the HCCI engine in most cases.