THE EFFECT OF GASOLINE FUEL TYPE ON SI ENGINE NITROGEN-OXIDES AND CARBON MONOXIDE EMISSIONS UNDER PART-LOAD OPERATING CONDITIONS

ABSTRACT

Six different gasoline blends with different antiknock agents and aromatics content were investigated for its influence on SI engine nitrogen-oxides and carbon monoxide emissions at part- load operating conditions. The six fuel types used were leaded gasoline with 0·5 g Pb/1, commercial unleaded gasoline, unleaded synthetic gasoline and its blends with different proportions of methyl tertiary butyl ether MTBE l10, 15 and 20 vol%). A four- stroke, four- cylinder, spark- ignition Regata engine (type 138 B 3.000) was used for conducting this study. The exhaust gases were analyzed for nitrogen-oxides and carbon monoxide emitted at part-load operating conditions for the speed range of 1000 to 3000 rpm. The results of this investigation have shown that blending unleaded synthetic gasoline with ethers such as MTBE reduces the aromatic content of the fuel. The 20 vol% MTBE-fuel blend gave the lowest carbon monoxide emissions of all blends used at part load condition. On the other hand, the 10 vol% MTBE-fuel blend gave the lowest nitrogen-oxides emission of all blends at part-load condition. The carbon monoxide concentration in engine exhaust differs between increase and decrease at part-load condition when fuel aromatics content increases. It was also found that as the gasoline aromatics content increases in the blend, the nitrogen-oxides concentration in engine exhaust increases. So, substitution of MTBE for the higher aromatics gasoline blends may help improving state environment and air quality.     

EFFECT OF METHYL TERTIARY BUTYL ETHER (MTBE) AS A GASOLINE ADDITIVE ON ENGINE PERFORMANCE AND EXHAUST EMISSIONS

The effect of blending unleaded gasoline with different proportions of methyl-t-butyl ether MTBE (10, 15 and 20 vol % ) on engine performance was studied using a fixed compression ratio SI engine (Opel 4 -cylinder ). The exhaust gases were analyzed for carbon monoxide, carbon dioxide and the hydrocarbons emitted. The results have shown that MTBE blends gave slightly better engine performance than the unleaded gasoline as evidenced by the power output. Analysis of exhaust gases shows better carbon monoxide and hydrocarbon emissions for all MTBE blends tested than unleaded gasoline. A higher carbon dioxide exhaust emission of the blends than the unleaded gasoline also confirms their better combustion. The 20 vol % MTBE blend gave the lowest carbon monoxide and hydrocarbon emissions of all blends used. A comparison was also made between a     

EFFECT OF METHYL TERTIARY BUTYL ETHER (MTBE) AS A GASOLINE ADDITIVE ON ENGINE PERFORMANCE AND EXHAUST EMISSIONS

ABSTRACT

The effect of blending unleaded gasoline with different proportions of methyl-t-butyl ether MTBE (10, 15 and 20 vol % ) on engine performance was studied using a fixed compression ratio SI engine (Opel 4 -cylinder ). The exhaust gases were analyzed for carbon monoxide, carbon dioxide and the hydrocarbons emitted. The results have shown that MTBE blends gave slightly better engine performance than the unleaded gasoline as evidenced by the power output. Analysis of exhaust gases shows better carbon monoxide and hydrocarbon emissions for all MTBE blends tested than unleaded gasoline. A higher carbon dioxide exhaust emission of the blends than the unleaded gasoline also confirms their better combustion. The 20 vol % MTBE blend gave the lowest carbon monoxide and hydrocarbon emissions of all blends used. A comparison was also made between a     

燃油组分对车用汽油机排放特性的影响分析

综述了燃油中烷烃、烯烃、芳烃等组分对于车用汽油机排放特性的影响。未燃烷烃是烷烃燃料HC排放的主要成分,烯烃燃料的HC排放主要包括丙烯、异丁烯、戊烯等,1,3-丁二烯的排放随燃油烯烃含量的增加而增加;苯、甲苯、乙苯等的排放随芳烃含量的增加而增加;发动机燃烧工况如空燃比、点火角度等对各种HC排放的具体组成有显著影响。因此,不仅需要加强降低燃油烯烃、芳烃含量的研究,也应该借助发动机燃烧过程的优化来降低因烯烃、芳烃含量高对排放造成的不利影响。     

Effect of Branched C8 Olefins Addition to Mexican Gasoline on Motor Vehicles Exhaust Emissions

Two groups of gasoline blends were prepared using a base-gasoline, containing 7.6% MTBE and added with either lower olefins (C₅-C₆) or butene's dimer (made up of 70% branched C₈-olefins). In each gasoline group, the olefin concentration was varied 5, 10, and 15 vol%. The dimer was produced in our pilot plant facilities from a mixture of n-butenes. An FTP-75 test procedure, performed on a 98 model year vehicle, was used to assess the effect of olefins type (C₅-C₆ or C₈) and their concentration in a gasoline blend on exhaust emissions; namely: CO, total hydrocarbons, NOx, and toxic compounds, such as aldehydes and ketones. Average CO emissions dropped 20-27%, when using 5-15 vol% C₈ olefins-gasoline, in comparison with those using C₅-C₆ olefins-gasolines. Total hydrocarbons emissions, on the other hand, remained practically unaffected either by the type of olefins or their concentrations (5-15 vol%). NOx emission factors decreased 10-14% when using the C₈ olefins-gasolines, relative to those containing lower olefins. Main toxic pollutants were formaldehyde, propanone, and acetaldehyde. In average, acetaldehyde emissions decreased 23-53% in the dimer-gasoline group, but formaldehyde emissions increased 5-39%, depending on the olefins content and in comparison with the lower olefins-gasolines.     

汽油中芳烃对发动机排放的影响

对我国典型炼油工艺生产的组分汽油进行分析、调合,采用发动机台架试验,考察了汽油中芳烃含量及种类对Ford DHE420发动机常规和非常规污染物排放的影响情况。结果表明,汽油中芳烃含量增加,尾气中CO排放增加,碳氢化合物和NO_x排放变化不明显,甲醛、甲醇和小分子烃类化合物排放减少,甲苯排放升高,1,3-丁二烯和苯排放几乎不变;烷基化汽油中加入7%的不同种类芳烃化合物不会显著影响发动机常规污染物排放,不同的芳烃在尾气中生成甲苯和苯的趋势各不相同。     

Effect of waste cooking-oil biodiesel on performance and exhaust emissions of a diesel engine

The ever increase in global energy demand, consumption of depletable fossil fuels, exhaust emissions and global warming, all these led to search about alternative fuels. Biodiesel was produced from waste cooking-oil by transesterification process. Blends of waste cooking-oil biodiesel and diesel oil were prepared in volume percentages of 10, 20 and 30% as B10, B20 and B30. Biodiesel blends have ASTM standards of physical and chemical characterization near to diesel fuel. Diesel engine performance and exhaust emissions were studied experimentally for burning waste cooking-oil blend with diesel fuel. This experimental was applied on a diesel engine at different engine loads from zero to full load. Thermal efficiencies for waste cooking-oil biodiesel blends were lower than diesel oil. Specific fuel consumptions of biodieselblends were higher than diesel fuel. Higher exhaust gas temperatures were recorded for biodiesel blends compared to diesel oil. CO₂ emissions for waste cooking-oil biodiesel blends were higher than diesel oil. CO, smoke opacity and HC emissions for biodiesel blends were lower than diesel fuel. NO_x emissions for biodiesel blends were higher than diesel fuel.     

采取有效技术对策降低汽车排放污染

汽车排放已成为大气污染的主要来源。一氧化碳、烃类和氮氧化物是三种主要排放有害物质。北京市有１４０万辆汽车,每年排出氮氧化物１４７ｋｔ。降低汽车排放污染需从改进汽车发动机系统、安装尾气三效转化器和提高汽油质量三方面采取措施。提高汽油质量,包括汽油无铅化,降低芳烃、烯烃和硫含量,降低蒸气压和９０％馏出温度,添加含氧化合物和清净分散剂可有效地控制汽车排放污染。为满足汽油新的质量要求,炼油厂需采取一整套技术进行技术改造。展望２１世纪,清洁的石油液体燃料仍将有竞争力,压缩天然气等替代燃料将有发展,燃料电池作为汽车动力将引人注目。     

汽油烃组成对汽车排放的影响

使用不同烃组成的6种汽油分别在满足国III、国IV排放标准的车型上进行了I型、IV型和VI型排放试验,研究了汽油烯烃、芳烃含量对常温冷启动后、低温冷启动后尾气排放和蒸发排放的影响。结果表明,汽油组成对排放的影响与汽车技术密切相关,满足国IV排放标准的车型上,当芳烃体积分数为35%、油品烯烃体积分数控制在25%时,HC,CO,NOx三种排放物较低;芳烃含量对排放的影响与发动机技术相关,但基本上呈现出芳烃含量较低时排放也较低的趋势;总蒸发排放物随油品烯烃含量增加而增加;油品的非烷烃类烃含量（即烯烃含量与芳烃含量之和）越高,车辆低温冷起动后HC、CO排放越高。     

Effect of cyclohexanol on phase stability and volatility behavior of hydrous ethanol-gasoline blends

Biofuels can contribute to reducing greenhouse gas emissions and bridging the gap between production and consumption. Ethanol is a renewable source of energy. It can reduce oil dependence and also can be appropriately used in gasoline as a blend. The high cost of dry ethanol has turned the researcher's attention to the more economic hydrous ethanol. However many works were focused on its impact on the engine performance and the exhaust emissions; few works were interested in the phase stability of those blends. This work aims to study the impact of blending cyclohexanol (CH) into hydrous ethanol-gasoline blends as a stabilizing agent. Four dual-alcohol (E5-3CH, E10-3CH, E15-3CH, and E20-3CH) blends were investigated besides their single hydrous ethanol (E0, E5, E10, E15, and E20) blends. The tests involved; water tolerance, distillation curve, and vapor pressure. Vapor lock protection potential, the area under the distillation curve (AUDC), and the area due to azeotrope formation (ADAF) were calculated. The obtained results show that cyclohexanol significantly increases the water tolerance of hydrous ethanol-gasoline blends. The blends of E5 and E10 which were separated at 30 °C converted into miscible and clear samples when they were blended with 3 vol% of cyclohexanol. These samples can also tolerate additional water. For E20, the addition of 3 vol% of cyclohexanol increased the water tolerance by about six times. Also, it was found that cyclohexanol does not have any negative effect on the volatility properties of the fuel blends. It was found that blending CH into the hydrous ethanol blends causes a significant increase in the AUDC and consequently, the area due to azeotrope formation (ADAF) decrease.     

汽油组成对进气阀及燃烧室沉积物性质的影响

The cleanliness of gasoline is related to its components and properties.All commercial gasoline builds up deposits on the engine’s injector,intake valve and combustion chamber,which can significantly lower the engine performance and influence exhaust gas emissions.In this study,the intake valve deposits (IVD) and combustion chamber deposits (CCD) produced from combustion of fuel containing 21 v%—42 v% of aromatics and 8 v%—31 v% of olefins have been studied using Ford engine tests,and the characteristics of deposits were studied by IR spectroscopy,TGA and elemental analysis instrument.The test results have shown that deposit formation depends on the fuel composition,especially the aromatic content in the fuel.It is also observed that there are differences in the values of IVD and CCD measured by IR spectrometry and elemental analyses.     

新油耗与排放法规下汽油发动机技术及对燃油的要求

阐述了我国油耗与排放法规的发展、现状与下一阶段的实施计划,从而探究在新油耗与排放法规下,汽油发动机技术、排放后处理技术的发展,及新技术的应用。通过多批次满足国Ⅳ和国Ⅴ排放标准汽油燃油的检测,分析了国Ⅴ排放标准实施后,汽油主要指标馏程、芳烃含量和蒸气压等发生的变化,阐明这些指标对汽油发动机和排放后处理新技术的影响,提出了汽油发动机技术对燃油的要求。结果表明,国Ⅴ排放标准实施后,汽油存在组分重、芳烃含量高、冬季蒸气压偏低等问题。在汽油发动机和排放后处理新技术应用下,这些问题会影响发动机的正常运行,同时导致车辆油耗的升高和排放恶化。因此,改善车辆油耗与排放,要求严格控制燃油指标,提升燃油品质。     

Performance and emissions characteristics of C.I. engine fueled with palm oil/palm oil methyl ester blended with diesel fuel

The rapid increasing worldwide demand for energy, continuous increasing of fuel consumption and the progressive depletion of fossil fuels led to an intensive search for biodiesel as alternative fuel for diesel engine. Performance and emissions characteristics of C.I. engine fueled with palm oil/palm oil methyl ester blended with diesel fuel is investigated experimentally. Biodiesel was prepared from palm oil by transesterification process. Diesel, biodiesel and palm oil blends were prepared in volume percentages of 20 and 100% as B20, B100 and PO20. Physical and chemical properties of biodiesel blends were near to diesel fuel. The experimental study is conducted on a diesel engine at different engine loading from zero to full loads using palm oil and palm biodiesel and its blends with diesel fuel. Thermal efficiency of biodiesel and oil blends with diesel fuel was lower than diesel fuel. Specific fuel consumptions for biodiesel and oil blends were found to be higher than diesel oil. Unburned hydrocarbons and carbon monoxide emissions have been decreased for biodiesel blends but it increased for oil blends compared to diesel fuel. Nitrogen oxide emissions have slightly been increased for biodiesel and oil blends compared to diesel fuel. Blends of diesel – biodiesel up to 20% biodiesel percentage by volume are recommended because of the improvement in performance and emissions as compared to diesel fuel.     

Influence of ethyl acetate addition on phase stability and fuel characteristics of hydrous ethanol-gasoline blends

Hydrous ethanol or commercial ethanol is regarded as a promising additive for gasoline. Its low cost and many other advantages, such as increasing the octane number and reduction of harmful emissions, motivate the researchers to investigate its use as an economic octane booster. The most common drawback of using hydrous ethanol as a gasoline additive is the phase separation problem. In this study, the effect of adding ethyl acetate (EA) on the phase stability, distillation curve, vapor pressure, vapor lock index and octane number of hydrous ethanol-gasoline blends was investigated. The reference fuel blends were formulated by mixing hydrous ethanol (96%) with hydrocarbon-based gasoline in different percentages (5, 10, 15 and 20?vol%). For studying the effect of ethyl acetate on the fuel specifications, it was mixed with 15% hydrous ethanol-gasoline blend in different percentage (3, 6, 9 and 12?vol%). The experimental results indicated that ethyl acetate has a good ability to increase the phase stability and the octane number of the hydrous ethanol-gasoline blends without causing adverse impacts on the other studied specifications.     

Octane Rating of Gasoline and Octane Booster Additives

Gasoline is a petroleum-derived liquid that is used primarily as a fuel in internal combustion engines (ICE), particularly spark ignition Otto Engine. Gasoline is a blend of hydrocarbons with some contaminants, including sulfur, nitrogen, oxygen, and certain metals. The four major constituent groups of gasoline are olefins, aromatics, paraffins, and napthenes. Octane number (ON) is measure of the ignition quality or flammability of gasoline. The ONs are Research Octane Number (RON) and Motor Octane Number (MON). RON is measured relative to a mixture of isooctane and n-heptane. Antiknock Index (AKI) is a measure of a fuel's ability to resist engine knock or octane quality. The AKI is an arithmetic average of RON and MON. The ON decreases with an increase chain length in the hydrocarbon molecule. The ONs increase with carbon chain branching. Another way of increasing the ON is used gasoline octane boosters as additives, such as tetraethyl lead (TEL), methyl tertiary-butyl ether (MTBE), and ferrocene. Aromatic alcohols, ethanol, and methanol also increase the ON of gasoline. The advantage to adding oxygenates, such as MTBE, methanol, and ethanol, to gasoline is that they cause very little pollution when they burn and are cleaner fuels.     

Properties of gasoline-ethanol-methanol ternary fuel blend compared with ethanol-gasoline and methanol-gasoline fuel blends

Two binary sets of gasoline-methanol (GM) and gasoline-ethanol (GE) blends along with two other ternary sets of gasoline-methanol-ethanol (GME) blends were formulated comprising single and dual alcohol. ASTM-D86 distillation, vapor pressure, and octane number were measured. Also, distillation curves were constructed for each blend and the influence of azeotrope formation was discussed. The obtained results reveal that distillation curves of gasoline blends, comprising from 5 to 15 vol% methanol, display a more significant decrease in distillation temperature than gasoline-ethanol blends. Also, more decrease in distillation temperature is observed by increasing the rate of blended alcohol. At equal rates of blended alcohol, the distillation curve of ternary fuel (GE5M5) is positioned in between distillation curves of binary fuel blends GM10 and GE10. More acceptable vapor pressure is achieved in ternary GEM fuels containing 7.5–15.0 vol% of dual alcohol, the same rate in GM blends increases vapor-lock tendency. At equal alcohol content, GEM blends give a higher octane number than GE one.     

EFFECT OF MTBE BLENDING ON THE PROPERTIES OF GASOLINE

The effect of blending MTBE in the gasoline was evaluated. MTBE effectively boost the octane numbers of gasoline without adversely effecting its other properties. However, MTBE is not as efficient as leadalkyl compounds as far as the specific octane number improvements are concerned. The addition of 5 to 30 volume percent MTBE increases 1.9 to 11.8 RON of a typical gasoline. MTBE addition also extends the volume of gasoline produces for a given crude by adding volume to the gasoline pool. MTBE provides much higher FEON to the gasoline in comparison with other gasoline components. A higher FEON increases the efficiency of the engine. MTBE is not affected by the lead level of the gasoline. For this reason, lost octane in future lead reductions of the gasoline in Saudi Arabia can be made up with MTBE. MTBE addition to the Saudi gasoline increases the RVP but within the specification of the gasoline. MTBE has favorable effect on the distillation characteristics of the gasoline. MTBE addition lowers the distillation temperature which improves driveability and cold engine operation. MTBEgasoline blends were found free of gums and peroxides after long term storage and pose no phase separation problems in the presence of water. MTBE is miscible in gasoline in all proportions and its solubility in water is low.     

EFFECT OF MTBE BLENDING ON THE PROPERTIES OF GASOLINE

ABSTRACT

The effect of blending MTBE in the gasoline was evaluated. MTBE effectively boost the octane numbers of gasoline without adversely effecting its other properties. However, MTBE is not as efficient as leadalkyl compounds as far as the specific octane number improvements are concerned. The addition of 5 to 30 volume percent MTBE increases 1.9 to 11.8 RON of a typical gasoline. MTBE addition also extends the volume of gasoline produces for a given crude by adding volume to the gasoline pool. MTBE provides much higher FEON to the gasoline in comparison with other gasoline components. A higher FEON increases the efficiency of the engine. MTBE is not affected by the lead level of the gasoline. For this reason, lost octane in future lead reductions of the gasoline in Saudi Arabia can be made up with MTBE. MTBE addition to the Saudi gasoline increases the RVP but within the specification of the gasoline. MTBE has favorable effect on the distillation characteristics of the gasoline. MTBE addition lowers the distillation temperature which improves driveability and cold engine operation. MTBEgasoline blends were found free of gums and peroxides after long term storage and pose no phase separation problems in the presence of water. MTBE is miscible in gasoline in all proportions and its solubility in water is low.     

Performance and emission characteristics of a diesel engine using Calophyllum Inophyllum biodiesel blends with TiO2 nanoadditives and EGR

An experimental investigation was carried out to evaluate the performance and emission characteristics of a single cylinder diesel engine by using Calophyllum Inophyllum biodiesel blends with TiO₂ nano additives and exhaust gas recirculation (EGR). The Calophyllum Inophyllum biodiesel-diesel blend was prepared by mixing 20% of Calophyllum Inophyllum biodiesel with 80% diesel (B20) in volumetric approach. The TiO₂ nanoparticles were dispersed into a B20 fuel with a dosage of 40?ppm to prepare the B2040TiO₂ fuel sample. The tests were conducted on a diesel engine by using B20, B2040TiO₂, B20?+?20%EGR, B2040TiO₂?+?20% EGR fuel samples at different load conditions. The brake thermal efficiency of B2040TiO₂, B2040 TiO₂?+?20%EGR fuels increased by 3.1%, 2.5%, and decreased by 1.8% for B20?+?20%EGR fuel compared to the B20 fuel at full load condition. The CO and HC emissions were reduced with the addition of TiO₂ nano particles to the B20 fuel and increased with the EGR method compared to the B20 fuel. The smoke emissions were increased by 16.23% and 12% for the B20?+?20%EGR and B2040TiO₂?+?20%EGR fuel samples compared to the B20 fuel at full load condition. The NOx emissions were reduced with the EGR technique and increased with the addition of TiO₂ nanoparticles to the biodiesel blend compared to the B20 fuel. It is concluded that Calophyllum Inophyllum biodiesel blend (B20) with the addition of TiO₂ nano particles and EGR technique exhibits better engine performance and reduced emissions compared to the other fuels.     

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阐述了液化石油气(LPG)燃料的供气方式，开发了一种适合465 LPG／汽油两用燃料发动机的供给装置，并对LPG燃料混合器的设计作了说明。利用该供给装置对465发动机燃用LPG和汽油燃料的动力、经济性能和排放特性进行了台架试验研究。结果表明：465发动机燃用LPG燃料时，在最大功率和最大转矩达到原汽油机94．4％以上的条件下；  外特性平均燃料消耗率降低4．6％；在怠速工况下，燃用LPG燃料时发动机尾气中的HC和CO排放量比原汽油机分别下降30．6％和46．4％。展示了液化石油气的应用前景。