Using of cotton oil soapstock biodiesel–diesel fuel blends as an alternative diesel fuel

In this study, usability of cotton oil soapstock biodiesel–diesel fuel blends as an alternative fuel for diesel engines were studied. Biodiesel was produced by reacting cotton oil soapstock with methyl alcohol at determined optimum condition. The cotton oil biodiesel–diesel fuel blends were tested in a single cylinder direct injection diesel engine. Engine performances and smoke value were measured at full load condition. Torque and power output of the engine with cotton oil soapstock biodiesel–diesel fuel blends decreased by 5.8% and 6.2%, respectively. Specific fuel consumption of engine with cotton oil soapstock–diesel fuel blends increased up to 10.5%. At maximum torque speeds, smoke level of engine with blend fuels decreased up to 46.6%, depending on the amount of biodiesel. These results were compared with diesel fuel values.     

Characterization and effect of using Mahua oil biodiesel as fuel in compression ignition engine

There is an increasing interest in India, to search for suitable alternative fuels that are environment friendly. This led to the choice of Mahua Oil (MO) as one of the main alternative fuels to diesel. In this investigation, Mahua Oil Biodiesel (MOB) and its blend with diesel were used as fuel in a single cylinder, direct injection and compression ignition engine. The MOB was prepared from MO by transesterification using methanol and potassium hydroxide. The fuel properties of MOB are close to the diesel and confirm to the ASTM standards. From the engine test analysis, it was observed that the MOB, B5 and B20 blend results in lower CO, HC and smoke emissions as compared to diesel. But the B5 and B20 blends results in higher efficiency as compared to MOB. Hence MOB or blends of MOB and diesel (B5 or B20) can be used as a substitute for diesel in diesel engines used in transportation as well as in the agriculture sector.     

Performance and emissions of a diesel tractor engine fueled with marine diesel and soybean methyl ester

Biodiesel is an alternative fuel that is cleaner than petrodiesel. Biodiesel can be used directly as fuel for a diesel engine without having to modify the engine system. It has the major advantages of having high biodegradability, excellent lubricity and no sulfur content. This paper presents the results of investigations carried out in studying the fuel properties of soybean methyl ester (SME) and its blend with marine diesel fuel from 5%, 20% and 50% blends by volume and in running a diesel engine with these fuels. The results indicate that the use of biodiesel produces lower smoke opacity (up to 74%), but higher brake specific fuel consumption (BSFC) (up to 12%) compared to marine fuel (MF). The measured carbon monoxide (CO) emissions of B5 and B100 fuels were found to be 3% and 52% lower than that of the MF, respectively.     

非直喷式增压柴油机燃用生物柴油的性能与排放特性

研究了非直喷式增压柴油机燃用柴油一生物柴油混合燃料的性能和排放特性。未对原机作任何调整和改动,研究了不同生物柴油掺混比例的混合燃料对功率、油耗、烟度和NOx排放的影响。结果表明：非直喷式柴油机燃用生物柴油后柴油机功率略有下降,油耗有所上升,烟度大幅下降,NOx排放增加明显。油耗、烟度和NOx的变化均与生物柴油掺混比例呈线性关系,合适的生物柴油掺混比例即可以保持柴油机的性能,又可有效地降低碳烟排放,且不引起NOx排放的显著变化。对于该增压柴油机,掺混生物柴油对外特性下的排放影响最大,影响最小的为标定转速下的负荷特性。不论是全负荷还是部分负荷,燃用生物柴油时低速下的烟度降低和NOx上升幅度均比高速时大,而同转速下高负荷时烟度降低和NOx上升更为明显。     

Performance of rapeseed oil blends in a diesel engine

The concept that 100% vegetable oil cannot be used safely in a direct-injection diesel engine for long periods of time has been stressed by many researchers. Short-term engine tests indicate good potential for vegetable oil fuels. Long-term endurance tests may show serious problems in injector coking, ring sticking, gum formation, and thickening of lubricating oil. These problems are related to the high viscosity and nonvolatility of vegetable oils, which cause inadequate fuel atomization and incomplete combustion. Fuel blending is one method of reducing viscosity. This paper presents the results of an engine test on three fuel blends. Test runs were also made on neat rapeseed oil and diesel fuel as bases for comparison. There were no significant problems with engine operation using these alternative fuels. The test results showed increases in brake thermal efficiency as the amount of rapeseed oil in the blends increases. Reduction of power-output was also noted with increased amount of rapeseed oil in the blends. Test results include data on performance and gaseous emissions. Crankcase oil analyses showed a reduction in viscosity. Friction power was noted to increase as the amount of diesel fuel in the blend increases.     

Experimental investigation of the performance and emissions of a heavy-duty diesel engine fueled with waste cooking oil biodiesel/ultra-low sulfur diesel blends

The major obstacle to biodiesel commercialization is the high cost of raw materials. Biodiesel from waste cooking oil is an economical source and thus an effective strategy for reducing the raw material cost. Using waste cooking oil also solves the problem of waste oil disposal. This study investigated the emissions of polycyclic aromatic hydrocarbons (PAHs), carcinogenic potencies and regulated matters, and brake specific fuel consumption from a heavy-duty diesel engine under the US-HDD transient cycle for five test fuels: ultra-low sulfur diesel (ULSD), WCOB5 (5 vol% biodiesel made from waste cooking oil + 95 vol% ULSD), WCOB10, WCOB20, and WCOB30. Experimental results indicate using ULSD/WCOB blends decreased PAHs by 7.53%-37.5%, particulate matter by 5.29%-8.32%, total hydrocarbons by 10.5%-36.0%, and carbon monoxide by 3.33%-13.1% as compared to using ULSD. The wide usage of WCOB blends as alternative fuels could protect the environment.     

Performance of jatropha oil blends in a diesel engine

Results are presented on tests on a single-cylinder direct-injection engine operating on diesel fuel, jatropha oil, and blends of diesel and jatropha oil in proportions of 97.4%/2.6%; 80%/20%; and 50%/50% by volume. The results covered a range of operating loads on the engine. Values are given for the chemical and physical properties of the fuels, brake specific fuel consumption, brake power, brake thermal efficiency, engine torque, and the concentrations of carbon monoxide, carbon dioxide and oxygen in the exhaust gases. Carbon dioxide emissions were similar for all fuels, the 97.4% diesel/2.6% jatropha fuel blend was observed to be the lower net contributor to the atmospheric level. The trend of carbon monoxide emissions was similar for the fuels but diesel fuel showed slightly lower emissions to the atmosphere. The test showed that jatropha oil could be conveniently used as a diesel substitute in a diesel engine. The test further showed increases in brake thermal efficiency, brake power and reduction of specific fuel consumption for jatropha oil and its blends with diesel generally, but the most significant conclusion from the study is that the 97.4% diesel/2.6% jatropha fuel blend produced maximum values of the brake power and brake thermal efficiency as well as minimum values of the specific fuel consumption. The 97.4%/2.6% fuel blend yielded the highest cetane number and even better engine performance than the diesel fuel suggesting that jatropha oil can be used as an ignition-accelerator additive for diesel fuel.     

Performance and emission characteristics of a diesel engine using isobutanol–diesel fuel blends

The aim of this study is to investigate the suitability of isobutanol–diesel fuel blends as an alternative fuel for the diesel engine, and experimentally determine their effects on the engine performance and exhaust emissions, namely break power, break specific fuel consumption (BSFC), break thermal efficiency (BTE) and emissions of CO, HC and NO_x. For this purpose, four different isobutanol–diesel fuel blends containing 5, 10, 15 and 20% isobutanol were prepared in volume basis and tested in a naturally aspirated four stroke direct injection diesel engine at full -load conditions at the speeds between 1200 and 2800 rpm with intervals of 200 rpm. The results obtained with the blends were compared to those with the diesel fuel as baseline. The test results indicate that the break power slightly decreases with the blends containing up to 10% isobutanol, whereas it significantly decreases with the blends containing 15 and 20% isobutanol. There is an increase in the BSFC in proportional to the isobutanol content in the blends. Although diesel fuel yields the highest BTE, the blend containing 10% isobutanol results in a slight improvement in BTE at high engine speeds. The results also reveal that, compared to diesel fuel, CO and NO_x emissions decrease with the use of the blends, while HC emissions increase considerably.     

Potential and challenges for large-scale application of biodiesel in automotive sector

Biodiesel is receiving serious attention globally as a potential alternative fuel for replacing mineral diesel, partially or fully. In this review paper, most prominent methods of biodiesel production commercially, life-cycle analysis and economic issues related to biodiesel, engine performance, combustion and emission characteristics including particulate, engine compatibility issues and effect of biodiesel usage on engine component wear and lubricating oil are comprehensively discussed. Majority of biodiesel produced globally is via base-catalyzed transesterification process since this is a low temperature and pressure process, having high conversion rates without intermediate steps, and it uses inexpensive materials of construction for the plant. Catalyst types (alkaline, acidic or enzymatic), catalyst concentration, molar ratio of alcohol/oil, reaction temperature, moisture content of reactants, and free fatty acid (FFA) content of oil are the main factors affecting biodiesel (ester) yield from the transesterification process. Substantial reduction in particulate matter (PM), total hydrocarbons (THC) and carbon monoxide (CO) emissions in comparison to mineral diesel, and increased brake specific fuel consumption (BSFC) and oxides of nitrogen (NO_X) emissions are reported by most researchers using unmodified compression ignition (CI) engines. This review covers several aspects, which are not covered by previous review articles, such as effect of biodiesel on unregulated emissions, effect of biodiesel on carbon deposits, wear of key engine components, and lubricating oil in long-term endurance studies. It emerges from literature review that even minor blends of biodiesel help control emissions and ease pressure on scarce petroleum resources without sacrificing engine power output, engine performance and fuel economy. This review underscores that future studies should focus on optimization of fuel injection equipment and hardware modifications to develop dedicated biodiesel engines, improve low temperature performance of biodiesel fuelled engines, develop new biodiesel compatible lubricating oil formulations and special materials for engine components before implementing large-scale substitution of mineral diesel by biodiesel globally.     

A study on the performance and emission of a diesel engine fueled with Jatropha biodiesel oil and its blends

Biodiesel either in neat form or as a mixture with diesel fuel is widely investigated to solve the twin problem of depletion of fossil fuels and environmental degradation. The main objective of the present study is to compare performance, emission and combustion characteristics of biodiesel derived from non edible Jatropha oil in a dual fuel diesel engine with base line results of diesel fuel. The performance parameters evaluated were: brake thermal efficiency, brake specific fuel consumption, power output. As a part of combustion study, in-cylinder pressure, rate of pressure rise and heat release rates were evaluated. The emission parameters such as carbon monoxide, carbon dioxide, un-burnt hydrocarbon, oxides of nitrogen and smoke opacity with the different fuels were also measured and compared with base line results. The different properties of Jatropha oil after transestrification were within acceptable limits of standards as set by many countries. The brake thermal efficiency of Jatropha methyl ester and its blends with diesel were lower than diesel and brake specific energy consumption was found to be higher. However, HC, CO and CO₂ and smoke were found to be lower with Jatropha biodiesel fuel. NO_x emissions on Jatropha biodiesel and its blend were higher than Diesel. The results from the experiments suggest that biodiesel derived from non edible oil like Jatropha could be a good substitute to diesel fuel in diesel engine in the near future as far as decentralized energy production is concerned. In view of comparable engine performance and reduction in most of the engine emissions, it can be concluded and biodiesel derived from Jatropha and its blends could be used in a conventional diesel engine without any modification.     

Performance and emissions characteristics of Jatropha oil (preheated and blends) in a direct injection compression ignition engine

The scarce and rapidly depleting conventional petroleum resources have promoted research for alternative fuels for internal combustion engines. Among various possible options, fuels derived from triglycerides (vegetable oils/animal fats) present promising “greener” substitutes for fossil fuels. Vegetable oils, due to their agricultural origin, are able to reduce net CO₂ emissions to the atmosphere along with import substitution of petroleum products. However, several operational and durability problems of using straight vegetable oils in diesel engines reported in the literature, which are because of their higher viscosity and low volatility compared to mineral diesel fuel.In the present research, experiments were designed to study the effect of reducing Jatropha oil’s viscosity by increasing the fuel temperature (using waste heat of the exhaust gases) and thereby eliminating its effect on combustion and emission characteristics of the engine. Experiments were also conducted using various blends of Jatropha oil with mineral diesel to study the effect of reduced blend viscosity on emissions and performance of diesel engine. A single cylinder, four stroke, constant speed, water cooled, direct injection diesel engine typically used in agricultural sector was used for the experiments. The acquired data were analyzed for various parameters such as thermal efficiency, brake specific fuel consumption (BSFC), smoke opacity, CO₂, CO and HC emissions. While operating the engine on Jatropha oil (preheated and blends), performance and emission parameters were found to be very close to mineral diesel for lower blend concentrations. However, for higher blend concentrations, performance and emissions were observed to be marginally inferior.     

Effects of oxyhydrogen on the CI engine fueled with the biodiesel blends: A performance,combustion and emission characteristics study

The main purpose of this study is to analyse the effects of oxy hydrogen (HHO) along with the Moringa oleifera biodiesel blend on engine performance, combustion and emission characteristics. HHO gases were generated using the typical electrolysis process using the potassium hydroxide solution. The experiments were performed under various engine loads of 25%, 50%, 75%, and 100% in a constant speed engine. Biodiesel from the M. oleifera was prepared by the transesterification process. Further, the procured biodiesel blends mixed with neat diesel at the concentration of 20% (B20) and 40% (B40). In addition to above, the HHO gas flow rate to the engine chamber maintained at the flow rate of 0.5 L^-1. The use of the 20% and 40% blends with HHO reported less BTE compared to the neat diesel. However, B20 reported marginal rise in the BTE due to the addition of the HHO gas. On the other hand, addition of HHO gas to the blends significantly dropped the brake specific fuel consumption. With regard to the emissions, addition of the biodiesel blends reduced the concentration of the CO, HC, and CO₂. Nevertheless, no reduction reported in the formation of the NO. However, adding the HHO to the biodiesel reduced the average NOx by 6%, which is a substantial effect. Overall, HHO enriching biodiesel blends are the potential replacement for the existing fossil fuels for its superior fuel properties compared to the conventional diesel.     

Experimental investigations of performance and emissions of Karanja oil and its blends in a single cylinder agricultural diesel engine

An experimental investigation has been carried out to analyze the performance and emission characteristics of a compression ignition engine fuelled with Karanja oil and its blends (10%, 20%, 50% and 75%) vis-a-vis mineral diesel. The effect of temperature on the viscosity of Karanja oil has also been investigated. Fuel preheating in the experiments – for reducing viscosity of Karanja oil and blends has been done by a specially designed heat exchanger, which utilizes waste heat from exhaust gases. A series of engine tests, with and without preheating/pre-conditioning have been conducted using each of the above fuel blends for comparative performance evaluation. The performance parameters evaluated include thermal efficiency, brake specific fuel consumption (BSFC), brake specific energy consumption (BSEC), and exhaust gas temperature whereas exhaust emissions include mass emissions of CO, HC, NO and smoke opacity. These parameters were evaluated in a single cylinder compression ignition engine typically used in agriculture sector of developing countries. The results of the experiment in each case were compared with baseline data of mineral diesel. Significant improvements have been observed in the performance parameters of the engine as well as exhaust emissions, when lower blends of Karanja oil were used with preheating and also without preheating. The gaseous emission of oxide of nitrogen from all blends with and with out preheating are lower than mineral diesel at all engine loads. Karanja oil blends with diesel (up to 50% v/v) without preheating as well as with preheating can replace diesel for operating the CI engines giving lower emissions and improved engine performance.     

Unregulated emissions and health risk potential from biodiesel (KB5, KB20) and methanol blend (M5) fuelled transportation diesel engines

Diesel engine emissions consist of several harmful gaseous species, some of which are regulated by stringent emission norms, while many others are not. These unregulated emission species are responsible for adverse environmental impact and serious health hazards upon prolonged exposure. In this study, a four-cylinder, 1.4 l, compression ignition (CI) engine was used for characterization of unregulated gaseous exhaust emissions measured at 2500 rpm at varying engine loads (0, 25, 50, 75 and 100%). The test fuels investigated were Karanja biodiesel blended with diesel (KB5, KB20), methanol blended with diesel (M5) and baseline mineral diesel. Fourier transform infrared (FTIR) emission analyzer was used to measure unregulated emission species and raw exhaust gas emission analyzer was used to measure regulated emission species in exhaust. Results show an increasing trend for some of the unregulated species from blends of biodiesel such as formaldehyde, acetaldehyde, ethanol, n-butane however methane reduced upon using these oxygenated fuel blends except methanol, compared to baseline mineral diesel. Nevertheless, no significant changes were observed for sulfur dioxide, iso-butane, n-octane, n-pentane, formic acid, benzene, acetylene and ethylene upon using biodiesel and methanol blends.     

Emission analysis of different blends of karanja oil with producer gas in a twin-cylinder diesel engine in dual fuel mode

The present study describes the emission analysis of different blends of karanja oil and diesel with producer gas in dual fuel mode using a twin-cylinder diesel engine in two cases of operations. In case 1, the above fuels are tested in single mode and in dual fuel mode operation at an optimum gas flow rate of 21.49 Kg/h under different load conditions. Similarly, in case 2 the same test fuels are used in dual fuel mode only at an optimum load of 10 kW under different gas flow rates. The study reveals that dual fuel operation of all test fuels shows lower smoke and oxide of nitrogen emissions compared to their single mode operation, whereas other emission parameters are on the higher side. However, all blended fuels show better emissions compared to diesel in both cases of operations.     

Emission analysis of different blends of karanja biodiesel with producer gas in a twin cylinder diesel engine in dual fuel mode

The present study demonstrates the emission analysis of different blends of Karanja biodiesel and diesel with producer gas in dual fuel mode using a twin cylinder diesel engine for two cases of operations. In case 1, a test is carried out using the above test fuels both in single mode and dual fuel mode operation with a constant gas flow rate of 21.49 Kg/h under different load conditions. Similarly, in case 2, a test is performed at a constant load of 10 kW under different gas flow rates using the same test fuels in the dual fuel mode only. The study reveals that all blended fuels show better emissions compared to diesel in both cases of operations. Dual fuel mode operation of all tested fuels shows lower smoke and oxide of nitrogen emissions compared to their single mode operation under all load conditions, whereas other emission parameters are found to be on the higher side.     

Investigating the emissions during acceleration of a turbocharged diesel engine operating with bio-diesel or n-butanol diesel fuel blends

Control of transient emissions from turbocharged diesel engines is an important objective for automotive manufacturers, since stringent criteria for exhaust emission levels must be met as dictated by the legislated transient cycles. On the other hand, bio-fuels are getting impetus today as renewable substitutes for conventional fuels (diesel fuel or gasoline), especially in the transport domain. In the present work, experimental tests are conducted on a turbocharged truck diesel engine in order to investigate the formation mechanism of NO (nitric oxide) and smoke under various accelerating schedules experienced during daily driving conditions. To this aim, a fully instrumented test bed was set up in order to capture the development of key engine and turbocharger variables during the transient events using ultra-fast response instrumentation for the instantaneous measurement of the exhaust NO and smoke opacity. Apart from the baseline diesel fuel, the engine was operated with a blend of diesel fuel with 30% bio-diesel, and a blend of diesel fuel with 25% n-butanol. Analytical diagrams are provided to explain the behavior of emissions development in conjunction with turbocharger and fueling response. Unsurprisingly, turbocharger lag was found to be the main culprit for the emissions spikes during all test cases examined. The differences in the measured exhaust emissions of the two bio-fuel/diesel fuel blends, both leading to serious smoke reductions but also NO increases compared with the baseline operation of the engine were determined and compared. The differing physical and chemical properties of bio-diesel and n-butanol against those of the diesel fuel, together with the formation mechanisms of NO and soot were used for the analysis and interpretation of the experimental findings concerning transient emissions.     

Combustion of fat and vegetable oil derived fuels in diesel engines

In this article, the status of fat and oil derived diesel fuels with respect to fuel properties, engine performance, and emissions is reviewed. The fuels considered are primarily the methyl esters of fatty acids derived from a variety of vegetable oils and animal fats, and referred to as biodiesel. The major obstacle to widespread use of biodiesel is the high cost relative to petroleum. Economics of biodiesel production are discussed, and it is concluded that the price of the feedstock fat or oil is the major factor determining biodiesel price.Biodiesel is completely miscible with petroleum diesel fuel, and is generally tested as a blend. The use of biodiesel in neat or blended form has no effect on the energy based engine fuel economy. The lubricity of these fuels is superior to conventional diesel, and this property is imparted to blends at levels above 20 vol%. Emissions of PM can be reduced dramatically through use of biodiesel in engines that are not high lube oil emitters. Emissions of NO_x increase significantly for both neat and blended fuels in both two- and four-stroke engines. The increase may be lower in newer, lower NO_x emitting four-strokes, but additional data are needed to confirm this conclusion. A discussion of available data on unregulated air toxins is presented, and it is concluded that definitive studies have yet to be performed in this area. A detailed discussion of important biodiesel properties and recommendations for future research is presented. Among the most important recommendations is the need for all future studies to employ biodiesel of well-known composition and purity, and to report detailed analyses. The purity levels necessary for achieving adequate engine endurance, compatibility with coatings and elastomers, cold flow properties, stability, and emissions performance must be better defined.     

Use of palm oil-based biofuel in the internal combustion engines: Performance and emissions characteristics

Palm oil (PO) was treated using different methods in order to use and test it as fuel in Compression Ignition (CI) engines. The treatments include PO preheated and preparation of PO/diesel oil blends, using mixtures of PO with waste cooking oil (WCO), which are converted into esters by a transesterification process. The purpose of this study is to evaluate the potential of the palm oil-based biofuels to replace diesel oil in CI engines.Tests were conducted in a single cylinder, four-stroke, air-cooled, direct injection diesel engine (no engine modifications were required). Experiments were initially carried out with diesel oil for providing baseline data. All the tested fuels have a low heating value compared to diesel fuel. A high fraction of PO in diesel fuel decreases the heating value of the blend. The brake thermal efficiency increases for the PO/Diesel blends. HC emissions for all those fuels except for the PO/Diesel blends are found lower, while CO emissions rise for all types of fuels. NO_x emissions are higher at low load, but lower at full load, for the engine fueled with PO and lower both at middle and full load for the engine fueled with the esters.     

A review on biodiesel production,combustion, emissions and performance

This article is a literature review on biodiesel production, combustion, performance and emissions. This study is based on the reports of about 130 scientists who published their results between 1980 and 2008. As the fossil fuels are depleting day by day, there is a need to find out an alternative fuel to fulfill the energy demand of the world. Biodiesel is one of the best available sources to fulfill the energy demand of the world. More than 350 oil-bearing crops identified, among which some only considered as potential alternative fuels for diesel engines. The scientists and researchers conducted tests by using different oils and their blends with diesel.A vast majority of the scientists reported that short-term engine tests using vegetable oils as fuels were very promising but the long-term test results showed higher carbon built up and lubricating oil contamination resulting in engine failure. They concluded that vegetable oils, either chemically altered or blended with diesel to prevent the engine failure. It was reported that the combustion characteristics of biodiesel are similar as diesel and blends were found shorter ignition delay, higher ignition temperature, higher ignition pressure and peak heat release. The engine power output was found to be equivalent to that of diesel fuel. In addition, it observed that the base catalysts are more effective than acid catalysts and enzymes.