Particulate Matter Emission Characteristics of a Biodiesel Fueled Engine at Idling Speed

Automotive and transportation sectors will be inclined towards the renewable or green energy in the near future. One of the green energy sources discovered recently is biodiesel. Biodiesel is a source of clean alternative fuel for internal combustion engines, which reduces the exhaust emissions significantly. Like diesel, biodiesel also emits exhaust particulate matter (PM), which is responsible for the black soot coming out from the diesel engine. However, it is not clear that what will be the size of PM formed during the idle speed of a biodiesel fueled engine. In this study, the characteristics of the exhaust particulate during the idling speed of a biodiesel fueled single cylinder diesel engine is analyzed. Biodiesel showed a positive result in terms of the concentration of emitted PM. However, particle sizes were smaller in case of biodiesel than diesel. Further studies should be carried out to improve the properties of biodiesel to ensure that the emitted particle sizes are not toxic to human health

On the Pressure Generated by Thermite Reactions Using Stress-Altered Aluminum Particles

This study examines pressure build-up and decay in thermites upon impact ignition and interprets reactivity based on the holistic pressure history. The thermite is a mixture of aluminum (Al) combined with bismuth trioxide (Bi2O3) powder. Four different Al particles sizes were examined that ranged from 100 nm to 18.5 μm mean diameter and for each size, two different Al powder treatments were examined: stress-altered compared to untreated, as-received Al powder. Stress-altered Al powders have been shown to be more reactive, such that the stress-altered Al powder thermites offer a metric for analyzing thermite reactivity in terms of pressure development compared to untreated Al powder. In a binary thermite system, multiple phase changes and interface chemistry influence the transient pressure response during reaction. Results reveal three key pressure metrics that need consideration specifically for thermite combustion: (1) delay time to peak pressure, (2) peak pressure, and (3) decay after peak pressure. Our experiments show that a lower peak pressure corresponds with higher thermite reactivity because aluminum consumption of oxygen generated by decomposing solid oxidizer reduces the peak pressure. Faster rates of reaction consume oxygen at higher rates such that pressure development becomes more limited than less reactive thermites and the result is a lower peak pressure. This conclusion is opposite of traditional studies using metal fuels with a gaseous environment that typically show higher peak pressures correspond with greater reactivity

On the Pressure Generated by Thermite Reactions Using Stress-Altered Aluminum Particles

This study examines pressure build-up and decay in thermites upon impact ignition and interprets reactivity based on the holistic pressure history. The thermite is a mixture of aluminum (Al) combined with bismuth trioxide (Bi2O3) powder. Four different Al particles sizes were examined that ranged from 100 nm to 18.5 μm mean diameter and for each size, two different Al powder treatments were examined: stress-altered compared to untreated, as-received Al powder. Stress-altered Al powders have been shown to be more reactive, such that the stress-altered Al powder thermites offer a metric for analyzing thermite reactivity in terms of pressure development compared to untreated Al powder. In a binary thermite system, multiple phase changes and interface chemistry influence the transient pressure response during reaction. Results reveal three key pressure metrics that need consideration specifically for thermite combustion: (1) delay time to peak pressure, (2) peak pressure, and (3) decay after peak pressure. Our experiments show that a lower peak pressure corresponds with higher thermite reactivity because aluminum consumption of oxygen generated by decomposing solid oxidizer reduces the peak pressure. Faster rates of reaction consume oxygen at higher rates such that pressure development becomes more limited than less reactive thermites and the result is a lower peak pressure. This conclusion is opposite of traditional studies using metal fuels with a gaseous environment that typically show higher peak pressures correspond with greater reactivity

Comparative Analysis on Property Improvement Using Fourier Transform Infrared Spectroscopy (FT-IR) and Nuclear Magnetic Resonance (NMR) (¹H and ¹³C) Spectra of Various Biodiesel Blended Fuels

The ever-increasing demand for energy has accelerated the research and development of renewable energy sources, which can eventually decrease the dependence on fossil fuel reserve. Biodiesel, a renewable energy source, has received considerable attention as an alternative fuel for the last few decades. In this study, biodiesels produced from two feedstocks were analyzed with a fatty acid methyl ester (FAME) composition, Fourier transform infrared (FT-IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy (1H and 13C), in order to improve their physicochemical properties and determine the relationships among them. Here, the physicochemical properties of biodiesels produced from C. nucifera, and P. pinnata oils and their 5%, 10%, 20%, and 30% (by volume) blends were compared with pure diesel (B0), according to ASTM D6751 standards. All of the biodiesels and their blends satisfied the conditions to be an alternative fuel, compared to diesel but pure C. nucifera biodiesel, and their blends yielded more property improvement through their physicochemical property analysis and had the lowest carbon residue content. FAME composition, FT-IR and NMR spectra analysis were used to show the better properties of C. nucifera biodiesel and its blends through high ester content, transmittance, and conversion rate, respectively, than P. pinnata biodiesel and thus can be considered for commercial use in diesel engines

Influence of polymethyl acrylate additive on the formation of particulate matter and NOX emission of a biodiesel-diesel-fueled engine.

The aim of this study is to investigate the effect of the polymethyl acrylate (PMA) additive on the formation of particulate matter (PM) and nitrogen oxide (NOX) emission from a diesel coconut and/or Calophyllum inophyllum biodiesel-fueled engine. The physicochemical properties of 20% of coconut and/or C. inophyllum biodiesel-diesel blend (B20), 0.03 wt% of PMA with B20 (B20P), and diesel fuel were measured and compared to ASTM D6751, D7467, and EN 14214 standard. The test results showed that the addition of PMA additive with B20 significantly improves the cold-flow properties such as pour point (PP), cloud point (CP), and cold filter plugging point (CFPP). The addition of PMA additives reduced the engine's brake-specific energy consumption of all tested fuels. Engine emission results showed that the additive-added fuel reduce PM concentration than B20 and diesel, whereas the PM size and NOX emission both increased than B20 fuel and baseline diesel fuel. Also, the effect of adding PMA into B20 reduced Carbon (C), Aluminum (Al), Potassium (K), and volatile materials in the soot, whereas it increased Oxygen (O), Fluorine (F), Zinc (Zn), Barium (Ba), Chlorine (Cl), Sodium (Na), and fixed carbon. The scanning electron microscope (SEM) results for B20P showed the lower agglomeration than B20 and diesel fuel. Therefore, B20P fuel can be used as an alternative to diesel fuel in diesel engines to lower the harmful emissions without compromising the fuel quality

Evaluation of the characteristics of non-oxidative biodiesels: A FAME composition, thermogravimetric and IR analysis

This experiment evaluates the effects of non-oxidative biodiesel (low oxygen content biodiesels) characteristics and their engine performances. Biodiesels produced from different feedstocks typically contains 10% to 15% oxygen by weight, which enhances the combustion quality and reduces the emissions of hydrocarbons (HCs) and carbon monoxide (CO). However, it produces a higher amount of nitrogen oxides (NOx) due to an increasing number of combustion products, resulting in a higher cylinder temperature. In addition, lean air-fuel mixtures can contribute to higher NOx emissions because biodiesel is more oxygenated than diesel. In this study, biodiesels produced from different feedstocks by a transesterification process were used to reduce the oxygen content by dipping an iron bar in the biodiesels, which absorbs oxygen and gets oxidized. Then, the oil characteristics, such as the percentage of saturated and unsaturated fatty acids, thermal degradation, stability and existing functional groups, were analyzed using fatty acid methyl ester (FAME) composition analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectroscopy analysis of neat biodiesel and non-oxidative biodiesel. Herein, Pongamia and Moringa biodiesels, containing normal and reduced weight percentages of oxygen, were evaluated to improve the quality and stability of biodiesels used in the diesel engine, which will also reduce the NOx emissions. Non-oxidative biodiesels had some positive effect on their properties, which can further reduce the NOx emissions. Herein, non-oxidative Pongamia and Moringa had quite similar characteristics and the former was observed to perform better in the reduction of NOx and other emissions as well

Study on stability, fuel properties, engine combustion, performance and emission characteristics of biofuel emulsion

This study reviewed papers related to biofuel emulsion, principally assessing the use of biofuel emulsion. The discussion is focused mainly on three active areas of emulsified biofuel, namely, exploration of various factors affecting the preparation of stable emulsion and its fuel properties, investigation of the effect of water concentration on physicochemical properties of fuel, and observation of the improvement and degradation of combustion, performance, and emission characteristics and the possible methods to enhance these characteristics

Study on stability, fuel properties, engine combustion, performance and emission characteristics of biofuel emulsion

This study reviewed papers related to biofuel emulsion, principally assessing the use of biofuel emulsion. The discussion is focused mainly on three active areas of emulsified biofuel, namely, exploration of various factors affecting the preparation of stable emulsion and its fuel properties, investigation of the effect of water concentration on physicochemical properties of fuel, and observation of the improvement and degradation of combustion, performance, and emission characteristics and the possible methods to enhance these characteristics. (c) 2015 Elsevier Ltd. All rights reserved

Impact of fatty acid composition and physicochemical properties of Jatropha and Alexandrian laurel biodiesel blends: An analysis of performance and emission characteristics

This experimental investigation deals with the effects of fatty acid methyl ester (FAME) composition and the physicochemical properties of biodiesel on engine performance and emissions. FAME compositions have a considerable influence on the physical and chemical properties of biodiesel, such as density, viscosity, heating value, cetane number (CN), oxidation stability, and cold flow properties. The performance and emissions of a four-cylinder turbocharged diesel engine were studied under varying speeds and full load condition. For this investigation, 10% and 20% blends of Jatropha (Jatropha curcas), Alexandrian laurel (Calophyllum inophyllum), and palm biodiesels (JB, ALB, and PB, respectively) were used, and the results were compared with that of the B5 fuel (95% diesel and 5% palm biodiesel). The content of saturated fatty acid (methyl palmitate) for ALB and JB was found to be 23.3% and 20.4% higher respectively than that for PB. In total, PB showed 19.8% higher saturation than JB, while ALB showed 7.3% higher saturation than JB because of their higher content of longer chain saturated fatty acid (methyl stearate). The CNs of all three biodiesels increased with the increase of carbon chain length and saturation level, whereas iodine value and saponification value decreased with the increase of saturation level. An average of 2.8% and 4.5% brake power reduction were observed in the case of 10% and 20% biodiesel blends respectively. Brake specific fuel consumption increased in the range of 6%–20% compared with B5 fuel, whereas carbon monoxide and hydrocarbon emissions decreased significantly. Nitrogen oxide emissions increased in the range of 9%–23% for the 10% and 20% biodiesel blends with respect to B5 fuel