Effects Of Ethanol Addition Research Articles

Laminar and kinetic burning characteristics of ethanol/methane/hydrogen fuel: Experimental and numerical analysis

In this essay, the effects of ethanol addition on the fuels of Hydrogen methane mixing fuel were discussed. The laminar burning characteristics of ethanol/hydrogen/methane mixture under different ethanol content, pressure (1 bar, 2 bar), and equivalence ratios (0.7–1.4) were experimentally and numerically simulated. Results show that increasing ethanol content reduces the laminar burning velocity (LBV) and shifts the peak LBV towards higher equivalence ratios, attributed to the fuel mixture's decreased average combustion heat. For a 20 % ethanol content, the LBV peak appears at φ = 1.3, while for 50 % and 80 % ethanol content, it appears at φ = 1.2 locations. An empirical correlation for LBV as a function of ethanol concentration was developed, demonstrating predictions within a 4 % error margin compared to experimental data. High accuracy fittings of activation energy, ethanol concentration, and equivalence ratio were achieved, with correlation coefficients exceeding 0.9. Numerical simulations pinpointed key reactions and the relationship between free radicals and LBV, highlighting a pronounced correlation between OH radicals and LBV under lean conditions (coefficient of 1.0583), and a strong correlation with H radicals under rich conditions (coefficient of 1.01657), this indicates that OH and H are involved in the key chain reaction that promote the burning process.

Effects of ethanol addition on caproic acid production and rumen microorganism community structure from straw fermentation

In order to enhance caproic acid concentration from wheat straw fermentation and elucidate the microbial community inside the system. This study investigated ethanol addition with different mode for wheat straw co-cultured with rumen fluid. The results showed that segmentation addition of ethanol resulted in a higher caproic acid of 1473 mg/L. The structural characteristics of the microorganism community were further analyzed to reveal the functional of microorganisms in the acid fermentation from straw. Among them, Prevotella had a strong hemicellulose degradation capacity; Corynebacterium, Ureibacillus, and Clostridium_sensu_stricto_12, were correlated with the increasing trend of caproic acid. Control the proper ethanol concentration and optimum fermentation conditions would avoid the biotoxicity for the microorganisms and enhance the product yield.

Effects of Ethanol Addition on Caproic Production and Rumen Microorganism Community Structure from Straw Fermentation

Effects of Ethanol Addition on Caproic Production and Rumen Microorganism Community Structure from Straw Fermentation

Effect of Nano-Magnetite and Ethanol on Methane Production in the Anaerobic Digestion of Wheat Straw

HighlightsStudied mesophilic and thermophilic anaerobic fermentation of wheat straw with nano-magnetite (Fe3O4) and ethanol.The maximum biogas yield of 421.5 mL/g in mesophilic AD was 60.8% higher than control.Revealed the mechanism of nano-Fe3O4 and ethanol addition to promote biogas production.Abstract. This study investigated the mesophilic and thermophilic anaerobic fermentation of wheat straw with nano-magnetite (Fe3O4) and ethanol addition. The effects of ethanol addition on the biogas yield, the degradation of lignocellulose, and the bacterial community were explored. The results showed that the biogas yield and methane content increased as the ethanol concentration increased. The ethanol concentration of 4 g/L resulted in highest biogas yield in mesophilic anaerobic fermentation at 421.5 mL/g, which was a 60.8% improvement compared to the control. The corresponding methane content was 66.2%. For the lignocellulose degradation, the cellulose and hemicellulose contents in mesophilic anaerobic fermentation were reduced from 55.42% and 17.19% of the pretreated wheat straw to between 22.88% and 25.98% and 11.60% and 13.05%, respectively. The microbial community results showed that as the ethanol content increased, the relative abundance of Firmicutes initially increased before it decreased. Among the microbial community results, the relative abundances of Firmicutes and Bacteroides in the biogas residue of the mesophilic anaerobic fermentation with the addition of 3 g/L of ethanol were the highest, at 31.26% and 30.94%, respectively. Keywords: Anaerobic Digestion, Biogas, Ethanol, Nano-Fe3O4, Wheat Straw.

Effects of Ethanol Addition on Caproic Production and Rumen Microorganism Community Structure from Straw Fermentation

Effects of Ethanol Addition on Caproic Production and Rumen Microorganism Community Structure from Straw Fermentation

Study on the laminar burning velocity of ethanol/RP-3 aviation kerosene premixed flame

Ethanol biofuel is one renewable liquid fuel which can mix with aviation kerosene and be used as the alternative fuel in aero-engine to release oil security as well as reduce CO2 emission. In the present work, experiments were carried out in a constant volume chamber to obtain the laminar burning velocity (LBV) of ethanol/RP-3 premixed flame. The effects of ethanol addition on the LBV of RP-3 were analyzed experimentally and theoretically. Experimental results show that with the increase of ethanol addition, the LBV of ethanol/RP-3 premixed flame increases. Theoretical analysis indicates that the chemical effect of ethanol addition on the LBV of ethanol/RP-3 plays a decisive role. The three effects of ethanol addition are in the order of chemical > dilution > thermal effect. Sensitivity analysis and reaction pathway analysis of ethanol/RP-3 combustion process shows that with the increase of ethanol addition, the formation of CH3, CH2O, and HCO increase due to the more active radical of OH participates in the primary reactions. In addition, the active radicals of H, O, and OH also increase because of the increase of ethanol addition, which promote the LBV of ethanol/RP-3 premixed flame.

Investigation into ethanol effects on combustion and particle number emissions in a spark-ignition to compression-ignition (SICI) engine

Spark assistance along with oxygenated components addition is a promising method to achieve stable compression ignition, high thermal efficiency and low particle emission. To this end, ethanol blended with non-oxygenated gasoline was fueled to an engine working with spark-ignition to compression-ignition (SICI) mode under air dilution and exhaust-diluted conditions. The effects of ethanol addition on engine performance including combustion characteristics, fuel economy, particle number (PN) emissions, were studied in two categories: changing research octane number (RON) by varying ethanol content and maintaining RON by changing fuel type. The results showed that ethanol addition by splash blending suppressed knock tendency, and the knock intensity could be lowered by up to 65–75% with increasing ethanol content. However, when maintaining the same RON, the ethanol-gasoline blend exhibited higher knock intensity than pure gasoline due to synergistic effects between ethanol and aromatics on auto-ignition. Compared to pure spark ignition with high-RON gasolines, using ethanol-gasoline blends under SICI could reduce the minimum fuel consumption rate by up to 25 g/(kW·h). To characterize the high-efficiency cycles under SICI, two dimensionless parameters were proposed by considering the ratios of heat release amount and duration between the flame propagation stage and auto-ignition stage. The two parameters showed good exponential correlation. As for emissions, blending ethanol could basically reduce PN emissions under SICI mode except for the cases with significant increase in nucleation particles, such as those with high knock intensity under stoichiometric condition and poor combustion quality under heavily exhaust-diluted conditions. The total PN reduction by blending ethanol is mainly due to the decrease of accumulation mode particles, during the stage of flame propagation rather than auto-ignition. Blending ethanol into non-oxygenated gasoline will directly increase unburned hydrocarbons and nitrogen oxides due to the low auto-ignition propensity of ethanol under stoichiometric or moderately lean conditions according to the temperature-pressure trajectory. Therefore, a dedicated combustion system with higher compression ratio and lean-boosted mixture is required to enhance ethanol's reactivity and achieve better fuel economy along with low PN emission for diluted SICI combustion.

Effects of Ethanol Addition on the Size Distribution of Liposome Suspensions in Water

Understanding the influence of ethanol on liposomes is important for insights into the physiological effects of ethanol on cell membranes and for transdermal drug delivery. In this work, different amounts of ethanol are added to liposome suspensions (1,2-dimyristoyl-sn-glycero-3-phosphocholine liposomes) of different initial sizes, and the size distributions are measured using dynamic light scattering. The average diameter reduces by 5–6% at a concentration of 20 vol % of ethanol, and the size distributions with and without ethanol are identical when scaled with the number-average diameter. The observed changes in diameter are significantly larger than the standard error of the measurements. Dilution of the liposome suspension containing 20 vol % ethanol with addition of water causes the liposomes to nearly regain their original size at that concentration; thus, the size change is reversible. The size measurements from dynamic light scattering are validated by cryo-transmission electron microscopy measurements, which show a similar reduction in the number-average diameter. ³¹P NMR studies also show a reduction in size upon addition of ethanol. The volume fraction of liposomes in the suspension, obtained from viscosity measurements, decreases by 9% with ethanol addition. A reduction of 4% in the number-average diameter is obtained upon adding 20 vol % ethanol to a suspension of giant liposomes, with the size distributions obtained by optical microscopy. Addition of cholesterol in the lipid membrane reduces the extent of shrinkage. The results indicate that the size reduction is due to shrinkage of liposomes and not due to breakage or dissolution and that the shrinkage is independent of the membrane curvature. Analysis shows that the decrease in size cannot be ascribed to membrane undulations alone when the increase in area per lipid molecule due to ethanol is taken into account. Addition of ethanol during the preparation of liposomes results in a much larger reduction in the average liposome diameter (up to 20%).

Effects of ethanol addition on soot particles dynamic evolution in ethylene/air laminar premixed flame

Effects of ethanol addition on soot particles dynamic evolution in ethylene/air laminar premixed flame

Effects of ethanol addition on exhaust characteristics and heat release rate for small diesel engine

Effects of ethanol addition on exhaust characteristics and heat release rate for small diesel engine

Laminar Burning Velocities of Fuels for Advanced Combustion Engines (FACE) Gasoline and Gasoline Surrogates with and without Ethanol Blending Associated with Octane Rating

ABSTRACTLaminar burning velocities of fuels for advanced combustion engines (FACE) C gasoline and of several blends of surrogate toluene reference fuels (TRFs) (n-heptane, iso-octane, and toluene mixtures) of the same research octane number are presented. Effects of ethanol addition on laminar flame speed of FACE-C and its surrogate are addressed. Measurements were conducted using a constant volume spherical combustion vessel in the constant pressure, stable flame regime at an initial temperature of 358 K and initial pressures up to 0.6 MPa with the equivalence ratios ranging from 0.8 to 1.6. Comparable values in the laminar burning velocities were measured for the FACE-C gasoline and the proposed surrogate fuel (17.60% n-heptane + 77.40% iso-octane + 5% toluene) over the range of experimental conditions. Sensitivity of flame propagation to total stretch rate effects and thermo-diffusive instability was quantified by determining Markstein length. Two percentages of an oxygenated fuel of ethanol as an additive, namely, 60 vol% and 85 vol% were investigated. The addition of ethanol to FACE-C and its surrogate TRF-1 (17.60% n-heptane + 77.40% iso-octane + 5% toluene) resulted in a relatively similar increase in the laminar burning velocities. The high-pressure measured values of Markstein length for the studied fuels blended with ethanol showed minimal influence of ethanol addition on the flame’s response to stretch rate and thermo-diffusive instability.

Effects of Ethanol Addition on the Efficiency of Subcritical Water Extraction of Proteins and Amino Acids from Porcine Placenta.

In a previous study, hydrolysates of porcine placenta were obtained and the extraction efficiency for proteins and amino acids was compared between sub- and super-critical water extraction systems; optimum efficiency was found to be achieved using subcritical water (170℃, 10 bar). In this study, the effects of adding ethanol to the subcritical water system were investigated. The lowest-molecular-weight extraction product detected weighed 434 Da, and the efficiency of extraction for low-molecular-weight products was increased when either the concentration of ethanol was decreased, or the extraction time was lengthened from 10 min to 30 min. The highest concentration of free amino acids (approximately 8 mM) was observed following 30 min extraction using pure distilled water. The concentration of free amino acids was significantly lower when ethanol was added or a shorter extraction time was used (p<0.05). Color change of the solution following extraction was measured. There were no significant differences in color between lysates produced with different extraction times when using distilled water (p>0.05); however, using different extraction times produced significant differences in color when using 20% or 50% ethanol solution for subcritical extraction (p<0.05). The range of pH for the hydrolysate solutions was 6.4-7.5. In conclusion, the investigated extraction system was successful in the extraction of ≤ 500 Da hydrolysates from porcine placenta, but addition of ethanol did not yield higher production of low-molecular-weight hydrolysates than that achieved by DW alone.

Effects of ethanol addition on biodiesel combustion: A modeling study

The present study aims to numerically investigate the impacts of ethanol blend ratio together with advanced fuel injection timings on biodiesel’s performance, combustion and emission characteristics. Simulations were conducted using coupled KIVA–CHEMKIN code for neat biodiesel and its blend fuels with 5%, 10% and 20% (vol.%) of ethanol at a fix engine speed of 2400rpm under 10%, 50% and 100% engine load conditions, with and without advanced fuel injection timings of 2°, 3° and 5° crank angle. A skeletal reaction mechanism was constructed to include the significant oxidation and emission formation kinetics of biodiesel and ethanol fuels, and it was validated by performing the 0-D ignition delay predictions, as well as 3-D numerical simulations against the experimental results. The results indicate that peak cylinder pressure and indicated thermal efficiency generally decrease with the increasing ethanol blend ratio due to its prolonged ignition delay and reduced heating value. In terms of emissions, the CO emissions generally increase as the ethanol blend ratio increases, while the NOx emissions are reduced. The soot emissions increases under 10% load conditions, but reduced under 50% and 100% load conditions. With advanced fuel injection timings, the combustion process seems to be improved under 10% and 100% engine load conditions. For the efficient use of biodiesel/ethanol blend fuels, it is suggested that the ethanol blend ratio and advanced fuel injection timing should be carefully selected based on the engine operating conditions.

The effects of ethanol addition with waste pork lard methyl ester on performance, emission and combustion characteristics of a diesel engine

In the recent research, as a result of depletion of world petroleum reserves, considerable attention has been focused on the use of different alternative fuels in diesel engines. The present work aims to ensure the possibility of adding ethanol as an additive with animal fat biodiesel that is tested as an alternative fuel for diesel in a CI engine. In this study, biodiesel is obtained from waste pork lard by base-catalyzed transesterification with methanol when potassium hydroxide as catalyst. 2.5%, 5% and 7.5% by volume of ethanol is blended with neat biodiesel in order to improve performance and combustion characteristics of a diesel engine. The experimental work is carried out in a 3.7 kW, single cylinder, naturally aspirated, water cooled, direct injection diesel engine for different loads and at a constant speed of 1500 rpm. The performance, emission and combustion characteristics of biodiesel-ethanol blends are investigated by comparing them with neat biodiesel and standard diesel. The experimental test results showed that the combustion and performance characteristics improved with the increase in percentage of ethanol addition with biodiesel. When compared to neat biodiesel and standard diesel, an increase in brake thermal efficiency of 5.8% and 4.1% is obtained for BEB7.5 blend at full load of the engine. With the increase in percentage of ethanol fraction in the blends, peak cylinder pressure and the corresponding heat release rate are increased. Biodiesel-ethanol blends exhibit longer ignition delay and shorter combustion duration when compared to neat biodiesel. Optimum reduction in carbon monoxide, unburned hydrocarbon and smoke emission are attained while using BEB5 blend at full load of the engine. However, there is an adverse effect in case of nitrogen oxide emission.

Effects of ethanol addition on formation of hydroxyapatite through hydrothermal treatment of dicalcium phosphate dihydrate

The mixture of dicalcium phosphate dihydrate (DCPD) and calcium acetate monohydrate were hydrothermally treated in a condition of water-ethanol mixed solvent at 120 °C for various periods. The rate of hydroxyapatite (HAp) formation was decreased with increasing the volume ratio of ethanol, to result in formation of dicalcium phosphate anhydrous and β-tricalcium phosphate. Needle-like HAp particles were observed in the sample treated with the mere water. The sample treated with the ethanol-water mixed solvent had nano-sized HAp particles with a form of the plate-like crystals. The size of HAp crystal was decreased with increasing the fraction of ethanol. These results show that HAp formation and crystal growth were prevented by the ethanol addition.

Effects of Ethanol Addition on Ignition Characteristics for Homogeneous Charge Compression Ignition Gasoline Engines (Second Report)

Effects of Ethanol Addition on Ignition Characteristics for Homogeneous Charge Compression Ignition Gasoline Engines (Second Report)

Effects of Ethanol Addition on Ignition Characteristics for Homogeneous Charge Compression Ignition Gasoline Engines

Effects of Ethanol Addition on Ignition Characteristics for Homogeneous Charge Compression Ignition Gasoline Engines

Effects of ethanol addition on the water sorption/solubility and percent conversion of comonomers in model dental adhesives

Objectives This study evaluated the kinetics of water uptake and percent conversion in neat versus ethanol-solvated resins that were formulated to be used as dental bonding agents. Methods Five methacrylate-based resins of known and increasing hydrophilicities (R1, R2, R3, R4 and R5) were used as reference materials. Resins were evaluated as neat bonding agents (100% resin) or they were solvated with absolute ethanol (95% resin/5% ethanol or 85% resin/15% ethanol). Specimens were prepared by dispensing the uncured resin into a circular mold (5.8 mm × 0.8 mm). Photo-activation was performed for 80 s. The water sorption/diffusion/solubility was gravimetrically evaluated, while the degree of conversion (DC) was calculated by Fourier-transform infrared spectroscopy. Results Water sorption increased with the hydrophilicity of the resin blends. In general, the solvated resins exhibited significantly higher water sorption, solubility and water diffusion coefficients when compared to their corresponding neat versions ( p < 0.05). The only exception was resin R1, the least hydrophilic resin, in which neat and solvated versions exhibited similar water sorption ( p > 0.05). Addition of ethanol increased the DC of all resins tested, especially of the least hydrophilic, R1 and R2 ( p < 0.05). Despite the increased DC of ethanol–solvated methacrylate-based resins, it occurs at the expense of an increase in their water sorption/diffusion and solubility values. Significance Negative effects of residual ethanol on water sorption/solubility appeared to be greater as the hydrophilicity of the resin blends increased. That is, the use of less hydrophilic resins in dental adhesives may create more reliable and durable bonds to dentin.

The influence of ethanol addition on premixed fuel-rich propene–oxygen–argon flames

The role of ethanol as a fuel additive was investigated in a fuel-rich, non-sooting (C/O = 0.77) flat premixed propene–oxygen–argon flame at 50 mbar (5 kPa). Mole fractions of stable and radical species were derived using two different in situ molecular beam mass spectrometry (MBMS) set-ups, one located in Bielefeld using electron impact ionization (EI), and the other at the Advanced Light Source (ALS) at Berkeley using vacuum UV photoionization (VUV-PI) with synchrotron radiation. A rich propene flame, previously studied in detail experimentally and with flame model calculations, was chosen as the base flame. Addition of ethanol is believed to reduce the concentrations of benzene and small aromatic compounds, while augmenting the formation of other regulated air toxics such as aldehydes. To study the chemical pathways responsible for these effects, quantitative concentrations of about 35 species were determined from both experiments. This is also the first time that a detailed comparison of quantitative species concentrations from these independent MBMS set-ups is available. Effects of ethanol addition on the species pool are discussed with special attention on benzene precursor chemistry and aldehyde formation.

Effects of Ethanol Addition and Ba/Ti Ratios on Preparation of Barium Titanate Nanocrystals Via a Spray Pyrolysis Method

BaTiO3 nanocrystals were synthesized by using a low‐pressure spray pyrolysis (SP) method. A new strategy was proposed to improve nanocrystal formation and phase evolution by ethanol addition and Ba/Ti molar ratio variation, respectively. A mixture of submicron and nanoparticles was found with SP of precursors without ethanol addition, while only nanoparticles could be obtained by ethanol addition. BaTiO3 crystal growth was improved by increasing the Ba/Ti ratio. In comparison, SP of the same precursor under atmospheric conditions resulted in only submicron particles with smooth surfaces and irregular morphology.