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1.
Safflower seed oil was chemically treated by the transesterification reaction in methyl alcohol environment with sodium hydroxide (NaOH) to produce biodiesel. The produced biodiesel was blended with diesel fuel by 5% (B5), 20% (B20) and 50% (B50) volumetrically. Some of important physical and chemical fuel properties of blend fuels, pure biodiesel and diesel fuel were determined. Performance and emission tests were carried out on a single cylinder diesel engine to compare biodiesel blends with petroleum diesel fuel. Average performance reductions were found as 2.2%, 6.3% and 11.2% for B5, B20 and B50 fuels, respectively, in comparison to diesel fuel. These reductions are low and can be compensated by a slight increase in brake specific fuel consumption (Bsfc). For blends, Bsfcs were increased by 2.8%, 3.9% and 7.8% as average for B5, B20 and B50, respectively. Considerable reductions were recorded in PM and smoke emissions with the use of biodiesel. CO emissions also decreased for biodiesel blends while NOx and HC emissions increased. But the increases in HC emissions can be neglected as they have very low amounts for all test fuels. It can be concluded that the use of safflower oil biodiesel has beneficial effects both in terms of emission reductions and alternative petroleum diesel fuel.  相似文献   

2.
Oleander oil has been used as raw material for producing biodiesel using ultrasonic irradiation method at the frequency of 20 kHz and horn type reactor 50 watt. A two-step transesterification process was carried out for optimum condition of 0.45 v/v methanol to oil ratio, 1.2% v/v H2SO4 catalyst, 45 °C reaction temperature and 15min reaction time, followed by treatment with 0.25 v/v methanol to oil ratio, 0.75% w/v KOH alkaline catalyst, 50 °C reaction temperature and 15 min reaction time. The fuel properties of Oleander biodiesel so obtained confirmed the requirements of both the standards ASTM D6751 and EN 14214 for biodiesel. Further Oleander biodiesel-diesel blends were tested to evaluate the engine performance and emission characteristics. The performance and emission of 20% Oleander biodiesel blend (B20) gave a satisfactory result in diesel engines as the brake thermal efficiency increased 2.06% and CO and UHC emissions decreased 41.4% and 32.3% respectively, compared to mineral diesel. Comparative investigation of performance and emissions characteristics of Oleander biodiesel blends and mineral diesel showed that oleander seed is a potential source of biodiesel and blends up to 20% can be used for realizing better performance from an unmodified diesel engine.  相似文献   

3.
金昌磊  苑丽质 《工业催化》2012,20(10):52-55
制备了酸性离子液体[(CH2)4SO3HMIM][HSO4]并用于催化潲水油制备生物柴油,研究了反应时间、反应温度、醇油物质的量比和剂油物质的量比等对酯交换反应转化率的影响,确定了较适宜的反应条件。结果表明,在反应时间4 h、反应温度140 ℃、醇油物质的量比12和剂油物质的量比0.08条件下,酯交换反应转化率为92.13%。制备的生物柴油达到了中国柴油机燃料调合用生物柴油(BD100)标准GB/T20828-2007。  相似文献   

4.
A household microwave (800W) was modified as a biodiesel reactor for continuous transethylation of waste frying palm oil. The high free fatty acid oil was simultaneously neutralized and transesterified with sodium hydroxide. With the ethanol to oil molar ratio of 12:1, 3.0% NaOH (in ethanol) and 30s residence time, the continuous conversion of waste frying palm oil to ethyl ester was over 97%. The waste palm oil biodiesel was then tested in a 100 kW diesel generator as a neat fuel (B100) and 50% blend with diesel No. 2 fuel (B50). The engine performance and emission are recorded. At the engine loads varied from 0 kW to 75 kW (at 25 kW intervals) of the maximum electrical rating, the performance of the neat and B50 are slightly lower than diesel No. 2 fuel. Emissions of NOx, CO and HC from B100 and B50 are lower than those of diesel No. 2 fuel, except that at the 75 kW engine load, where the B100 emits higher levels of NOx than the diesel No. 2 fuel.  相似文献   

5.
This work investigates the impacts on fuel consumption and exhaust emissions of a diesel power generator operating with biodiesel. Fuel blends with 5%, 20%, 35%, 50%, and 85% of soybean biodiesel in diesel oil, and fuel blends containing 5%, 20%, and 35% of castor oil biodiesel in diesel oil were tested, varying engine load from 9.6 to 35.7 kW. Specific fuel consumption (SFC) and the exhaust concentrations of carbon dioxide (CO2), carbon monoxide (CO), and hydrocarbons (HC) were evaluated. The engine was kept with its original settings for diesel oil operation. The results showed increased fuel consumption with higher biodiesel concentration in the fuel. Soybean biodiesel blends showed lower fuel consumption than castor biodiesel blends at a given concentration. At low and moderate loads, CO emission was increased by nearly 40% and over 80% when fuel blends containing 35% of castor oil biodiesel or soybean biodiesel were used, respectively, in comparison with diesel oil. With the load power of 9.6 kW, the use of fuel blends containing 20% of castor oil biodiesel or soybean biodiesel increased HC emissions by 16% and 18%, respectively, in comparison with diesel oil. Exhaust CO2 concentration did not change significantly, showing differences lower than ±3% of the values recorded for diesel oil operation, irrespective of biodiesel type, concentration and the load applied. The results demonstrate that optimization of fuel injection system is required for proper engine operation with biodiesel.  相似文献   

6.
In this study, the optimum conditions (methanol/oil mole ratio, temperature, and so on) for producing biodiesel with fish oil (menhaden oil) were established. The length of the carbon chain of fish oil is frequently greater than that of general vegetable oils. Therefore, the use of fish-oil based biodiesel with larger cetane number may improve diesel engine performance and result in a reduction of pollutant emissions. The optimum conditions of the manufacture of biodiesel with menhaden oil were reaction time of 120 min, reaction temperature of 55 °C, methanol/fish oil molar ratio of 12, and alkaline catalyst content of 2.0 wt%. In the performance evaluation of the biodiesel produced, the acid value (0.20 mg KOH/g), kinematic viscosity (4.60 cSt at 40 °C), and higher heating value (42.1 MJ/k) biodiesel quality standards were suitable.  相似文献   

7.
以精制棉籽油、无水甲醇和二乙二醇单甲醚为原料,KOH为催化剂,通过酯交换反应制备出一种高含氧量的新型生物柴油;采用正交试验研究了醇油比、催化剂用量、温度和反应时间对产率的影响,得出了最佳合成条件;运用红外光谱法、核磁共振法、凝胶渗透色谱法进行了产物结构表征;此外柴油机台架试验也表明燃烧该新型生物柴油可有效减少柴油机的废气排放。  相似文献   

8.
Jordan relies heavily on expensive and unreliable imported oil. Therefore, this study was initiated to investigate the potential of ethyl ester used as vegetable oil (VO; biodiesel) to substitute oil-based diesel fuel. The fuels tested were several ester/diesel blends including 100% ester in addition to diesel fuel, which served as the baseline fuel. Variable-speed tests were run on all fuels on a standard test rig of a single-cylinder, direct-injection diesel engine. Tests were conducted to compare these blends with the baseline local diesel fuel in terms of engine performance and exhaust emissions. The results indicated that the blends burned more efficiently with less specific fuel consumption, and therefore, resulted in higher engine thermal efficiency. Furthermore, the blends produced less carbon monoxide and unburned hydrocarbons than diesel fuel. The 100% ester fuel and the blend of 75:25 ester/diesel gave the best performance while the 50:50 blend consistently resulted in the lowest amounts of emissions over the whole speed range tested.  相似文献   

9.
《Fuel》2007,86(12-13):1772-1780
In this study, wasted cooking oil from restaurants was used to produce neat (pure) biodiesel through transesterification, and this converted biodiesel was then used to prepare biodiesel/diesel blends. The goal of this study was to compare the trace formation from the exhaust tail gas of a diesel engine when operated using the different fuel type: neat biodiesel, biodiesel/diesel blends, and normal diesel fuels. B20 produced the lowest CO concentration for all engine speeds. B50 produced higher CO2 than other fuels for all engine speeds, except at 2000 rpm where B20 gave the highest. The biodiesel and biodiesel/diesel blend fuels produced higher NOx for various engine speeds as expected. SO2 formation not only showed an increasing trend with increased engine speed but also showed an increasing trend as the percentage of diesel increased in the fuels. Among the collected data, the PM concentrations from B100 engines were higher than from other fuelled engines for the tested engine speed and most biodiesel-contained fuels produced higher PM than the pure diesel fuel did. Overall, we may conclude that B20 and B50 are the optimum fuel blends. The species of trace formation in the biodiesel-contained fuelled engine exhaust were mainly CnH2n+2, DEP, and DPS. For the B100, B80, B50, and D fuelled engines, C15H32 was the dominant species for all engine speeds, while squalene (C30H50) was the dominant for B20. DEP was only observed in the B100, B80, and B50 fuelled engines in this study. The D fuelled engine showed a higher DPS production for engine speeds higher than 1200 rpm.  相似文献   

10.
Renewable energy sources are attracting more attention due to lower cost and lower pollution relative to fossil fuels. The aim of this experimental work is the production of renewable and clean methyl ester from pomace oil as an alternative fuel. This oil was obtained from pomace which is the waste of olive oil plants. Optimum producing conditions were determined experimentally. The maximum yield was obtained at 30% of methanol/oil ratio, 60 °C temperature for 60 min with NaOH catalyst. The properties of the biodiesel thus obtained were compared with diesel fuel requirements. An organic based Manganese additive improved the biodiesel properties. Doping the fuel at a ratio of 12 μmol/l oil methyl ester led to a 20.37% decrease in viscosity, 7 °C fall in the flash point and reduced the pour point from 0 °C to −15 °C. This blend of pomace oil methyl ester-diesel fuel with manganese additive was tested in a direct injection diesel engine. The maximum effect of the new fuel blend and diesel fuel on engine performance was obtained at 1400 rpm.  相似文献   

11.
Waste anchovy fish oils transesterification was studied with the purpose of achieving the conditions for biodiesel usage in a single cylinder, direct injection compression ignition. With this purpose, the pure biodiesel produced from anchovy fish oil, biodiesel-diesel fuel blends of 25%:75% biodiesel-diesel (B25), 50%:50% biodiesel-diesel (B50), 75%:25% biodiesel-diesel (B75) and petroleum diesel fuels were used in the engine to specify how the engine performance and exhaust emission parameters changed. The fuel properties of test fuels were analyzed. Tests were performed at full load engine operation with variable speeds of 1000, 1500, 2000 and 2500 rpm engine speeds. As results of investigations on comparison of fuels with each other, there has been a decrease with 4.14% in fish oil methyl ester (FOME) and its blends' engine torque, averagely 5.16% reduction in engine power, while 4.96% increase in specific fuel consumption have been observed. On one hand there has been average reduction as 4.576%, 21.3%, 33.42% in CO2, CO, HC, respectively; on the other hand, there has been increase as 9.63%, 29.37% and 7.54% in O2, NOx and exhaust gas temperature has been observed. It was also found that biodiesel from anchovy fish oil contains 37.93 wt.% saturated fatty acids which helps to improve cetane number and lower NOx emissions. Besides, for biodiesel and its blends, average smoke opacity was reduces about 16% in comparison to D2. It can be concluded that waste anchovy fish obtained from biodiesel can be used as a substitute for petroleum diesel in diesel engines.  相似文献   

12.
The effects of diesel oil-soybean biodiesel blends on a passenger vehicle exhaust pollutant emissions were investigated. Blends of diesel oil and soybean biodiesel with concentrations of 3% (B3), 5% (B5), 10% (B10) and 20% (B20) were used as fuels. Additionally, the effects of anhydrous ethanol as an additive to B20 fuel blend with concentrations of 2% (B20E2) and 5% (B20E5) were also studied. The emissions tests were carried out following the New European Driving Cycle (NEDC). The results showed that increasing biodiesel concentration in the fuel blend increases carbon dioxide (CO2) and oxides of nitrogen (NOX) emissions, while carbon monoxide (CO), hydrocarbons (HC) and particulate matter (PM) emissions are reduced. The addition of anhydrous ethanol to B20 fuel blend proved it can be a strategy to control exhaust NOX and global warming effects through the reduction of CO2 concentration. However, it may require fuel injection modifications, as it increases CO, HC and PM emissions.  相似文献   

13.
棉籽油酯交换法合成生物柴油的工艺研究   总被引:6,自引:0,他引:6  
介绍了利用复合碱性催化棉籽油酯交换合成生物柴油的工艺过程,正交实验得出的适宜工艺条件为:醇油摩尔比为5.5∶1,反应时间50 min,反应温度35℃,催化剂用量1.0%,产率可达96%。并比较了生物柴油与0#柴油的性能。  相似文献   

14.
C.H. Cheng  C.S. Cheung  T.L. Chan  S.C. Lee  C.D. Yao  K.S. Tsang   《Fuel》2008,87(10-11):1870-1879
Biodiesel is an alternative fuel for internal combustion engines. It can reduce carbon monoxide (CO), hydrocarbon (HC) and particulate matter (PM) emissions, compared with diesel fuel, but there is also an increase in nitrogen oxides (NOx) emission. This study is aimed to compare the effect of applying a biodiesel with either 10% blended methanol or 10% fumigation methanol. The biodiesel used in this study was converted from waste cooking oil. Experiments were performed on a 4-cylinder naturally aspirated direct injection diesel engine operating at a constant speed of 1800 rev/min with five different engine loads. The results indicate a reduction of CO2, NOx, and particulate mass emissions and a reduction in mean particle diameter, in both cases, compared with diesel fuel. It is of interest to compare the two modes of fueling with methanol in combination with biodiesel. For the blended mode, there is a slightly higher brake thermal efficiency at low engine load while the fumigation mode gives slightly higher brake thermal efficiency at medium and high engine loads. In the fumigation mode, an extra fuel injection control system is required, and there is also an increase in CO, HC and NO2 (nitrogen dioxide) and particulate emissions in the engine exhaust, which are disadvantages compared with the blended mode.  相似文献   

15.
Non-edible jatropha (Jatropha curcas), karanja (Pongamia pinnata) and polanga (Calophyllum inophyllum) oil based methyl esters were produced and blended with conventional diesel having sulphur content less than 10 mg/kg. Ten fuel blends (Diesel, B20, B50 and B100) were tested for their use as substitute fuel for a water-cooled three cylinder tractor engine. Test data were generated under full/part throttle position for different engine speeds (1200, 1800 and 2200 rev/min). Change in exhaust emissions (Smoke, CO, HC, NOx, and PM) were also analyzed for determining the optimum test fuel at various operating conditions. The maximum increase in power is observed for 50% jatropha biodiesel and diesel blend at rated speed. Brake specific fuel consumptions for all the biodiesel blends with diesel increases with blends and decreases with speed. There is a reduction in smoke for all the biodiesel and their blends when compared with diesel. Smoke emission reduces with blends and speeds during full throttle performance test.  相似文献   

16.
Biodiesel is currently considered as the most promising substitute for diesel fuel because of its similar properties to diesel. This study presents the use of the supercritical methanol method in the production of biodiesel from Croton megalocarpus oil. The reaction parameters such as methanol‐to‐oil ratio, reaction temperature and reaction time were varied to obtain the optimal reaction conditions by design of experiment, specifically, response surface methodology based on three‐variable central composite design with α = 2. It has been shown that it is possible to achieve methyl ester yields as high as 74.91 % with reaction conditions such as 50:1 methanol‐to‐oil molar ratio, 330 °C reaction temperature and a reaction period of 20 min. However, Croton‐based biodiesel did not sustain higher temperatures due to decomposition of polyunsaturated methyl linoleate, which is dominant in biodiesel. Lower yields were observed when higher temperatures were used during the optimization process. The supercritical methanol method showed competitive biodiesel yields when compared with catalytic methods.  相似文献   

17.
Chao He  Yunshan Ge  Jianwei Tan  Xiukun Han 《Fuel》2010,89(8):2040-10343
With mutagenic and carcinogenic potential, polycyclic aromatic hydrocarbons (PAHs) from mobile source exhaust have contributed to a substantial share of air toxics. In order to characterize the PAHs emissions of diesel engine fueled with diesel, biodiesel (B100) and its blend (B20), an experimental study has been carried out on a direct-injection turbocharged diesel engine. The particle-phase and gas-phase PAHs in engine exhaust were collected by fiberglass filters and “PUF/XAD-2/PUF” cartridges, respectively, then the PAHs were determined by a gas chromatograph/mass spectrometer (GC/MS). The experimental results indicated that comparing with diesel, using B100 and B20 can greatly reduce the total PAHs emissions of diesel engine by 19.4% and 13.1%, respectively. The Benzo[a]Pyrene (BaP) equivalent of PAHs emissions were also decreased by 15.0% with the use of B100. For the three fuels, the gas-phase PAHs emissions were higher than particle-phase PAHs emissions and the most abundant PAH compounds from engine exhaust were naphthalene and phenanthrene. The analysis showed that there was a close correlation between total PAHs emissions and particulate matter (PM) emissions for three fuels. Furthermore, the correlation became more significant when using biodiesel.  相似文献   

18.
《Fuel》2006,85(14-15):2187-2194
In this present investigation deccan hemp oil, a non-edible vegetable oil is selected for the test on a diesel engine and its suitability as an alternate fuel is examined. The viscosity of deccan hemp oil is reduced first by blending with diesel in 25/75%, 50/50%, 75/25%, 100/0% on volume basis, then analyzed and compared with diesel. Further blends are heated and effect of viscosity on temperature was studied. The performance and emission characteristics of blends are evaluated at variable loads of 0.37, 0.92, 1.48, 2.03, 2.58, 3.13 and 3.68 kW at a constant rated speed of 1500 rpm and results are compared with diesel. The thermal efficiency, brake specific fuel consumption (BSFC), and brake specific energy consumption (BSEC) are well comparable with diesel, and emissions are a little higher for 25% and 50% blends. At rated load, smoke, carbon monoxide (CO), and unburnt hydrocarbon (HC) emissions of 50% blend are higher compared with diesel by 51.74%, 71.42% and 33.3%, respectively. For ascertaining the validity of results obtained, pure deccan hemp oil results are compared with results of jatropha and pongamia oil for similar works available in the literature and were well comparable. From investigation it has been established that, up to 25% of blend of deccan hemp oil without heating and up to 50% blend with preheating can be substituted for diesel engine without any engine modification.  相似文献   

19.
Exhaust emissions and their effects on the environment and human health, such as mutagenicity of particulate matter (PM) and ozone-forming potential, must be considered when using an alternative fuel. In the present work, a test engine and two agricultural tractors ran on rapeseed oil methyl ester (biodiesel) or conventional diesel fuel as well as blends thereof. The objective was to detect any disproportionately positive or negative effects depending on blend levels, because conventional diesel fuel and biodiesel can be blended in every ratio. Generally, emissions of regulated compounds changed linearly with the blend level. The known positive and negative effects of biodiesel varied accordingly. Overall, no optimal blend was found. Increasing biodiesel content of the fuel caused a linear increase in benzene emissions in the agricultural five-mode engine test, an effect that may be explained from previous studies on precombustion chemistry. In using the test engine, it was found that PM from biodiesel significantly reduced mutagenic potential compared with that from diesel fuel, although in this work PM masses were found to be reproducibly higher for biodiesel from rapeseed oil compared with conventional diesel fuel. Ozone precursors increased 10–30% when using biodiesel compared with conventional diesel fuel. Emissions of aldehydes and alkenes are mainly responsible for this effect. N2O emissions increased when using a catalytic converter.  相似文献   

20.
Xingcai Lü  Yuchun Hou  Linlin Zu  Zhen Huang 《Fuel》2006,85(17-18):2622-2631
This article investigates the auto-ignition, combustion, and emission characteristics of homogeneous charge compression ignition (HCCI) combustion engines fuelled with n-heptane and ethanol/n-heptane blend fuels. The experiments were conducted on a single-cylinder HCCI engine using neat n-heptane, and 10%, 20%, 30%, 40%, and 50% ethanol/n-heptane blend fuels (by volume) at a fixed engine speed of 1800 r/min. The results show that, with the introduction of ethanol in n-heptane, the maximum indicated mean effective pressure (IMEP) can be expanded from 3.38 bar of neat n-heptane to 5.1 bar, the indicated thermal efficiency can also be increased up to 50% at large engine loads, but the thermal efficiency deteriorated at light engine load. Due to the much higher octane number of ethanol, the cool-flame reaction delays, the initial temperature corresponding the cool-flame reaction increases, and the peak value of the low-temperature heat release decreases with the increase of ethanol addition in the blend fuels. Furthermore, the low-temperature heat release is indiscernible when the ethanol volume increases up to 50%. In the case of the neat n-heptane and 10% ethanol/n-heptane blends, the combustion duration is very short due to the early ignition timing. For 20–50% ethanol/n-heptane blend fuels, the ignition timing is gradually delayed to the top dead center (TDC) by the ethanol addition. As a result, the combustion duration prolongs obviously at the same engine load when compared to the neat n-heptane fuel. At overall stable operation ranges, the HC emissions for n-heptane and 10–30% ethanol/n-heptane blends are very low, while HC emissions increase substantially for 40% and 50% ethanol/n-heptane blends. CO emissions show another tendency compared to HC emissions. At the engine load of 1.5–2.5 bar, CO emissions are very high for all fuels. Beside this range, CO emissions decrease both for large load and light load. In terms of operation stability of HCCI combustion, for a constant energy input, n-heptane shows an excellent repeatability and light cycle-to-cycle variation, while the cycle-to-cycle variation of the maximum combustion pressure and its corresponding crank angle, and ignition timing deteriorated with the increase of ethanol addition.  相似文献   

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