Use Of Straight Vegetable Oil Research Articles

Performance of a Diesel Engine Run with Kerosene–Rapeseed Oil Blends Doped with Ignition Promoters

<div>The use of straight vegetable oil in diesel engines leads to undesirable consequences due to the peculiar physicochemical properties of vegetable oils. In this regard, the use of pure and unmodified vegetable oils requires their obligatory dilution with petroleum fuels, usually diesel fuel. However, blends of diesel fuel with vegetable oil have a significantly higher density and viscosity than pure diesel fuels. Therefore, in this article, it was proposed to use blends of vegetable oil with aviation kerosene since kerosene has lower density and viscosity compared to diesel fuel. In addition, kerosene is less prone to coking of injectors, has a higher calorific value, and has a lighter hydrocarbon composition, which makes starting the engine easier. Within the framework of the study, engine tests of a full-size four-cylinder diesel engine, MMZ D-245.12.C, were carried out at maximum load in the range of crankshaft speeds from minimum (1000 min<sup>−1</sup>) to nominal (2400 min<sup>−1</sup>). Various blends of kerosene with rapeseed oil with an oil content of 10 to 50% by volume have been tested. Ignition promoters were introduced into the fuel blends to improve their combustion. Commercial ethylhexyl nitrate was used as an ignition promoter. In addition, experimental additives were investigated, which are the FAMEs of vegetable oils oxidized to various concentrations of peroxide compounds. It has been shown that blends of kerosene and rapeseed oil doped with ignition promoters can be successfully used in diesel engines. The engine showed the maximum power and the lowest level of smoke emissions when running on a blend of kerosene and rapeseed oil with the addition of oxidized FAME of olive oil with a peroxide content of 1.1 g OOH/100 g.</div>

Performance Study of 4-Stroke Diesel Engine Using Soybean Oil Blend


 
 
 
 The rate of fossil fuel consumption is soaring with population growth but the fossil fuel reserves are finite in nature. It is only a matter of when they run out - not if. Every year, billions of tons of fossil fuel oil is consumed globally. So it is high time we contemplated over other alternative fuels. One such alternative is the use of Straight Vegetable Oil (SVO) or its blend in diesel engine if performance, emission and maintenance of an engine are comparable to diesel fuel. The main objective of this research was to evaluate the effectiveness of commercially available Soybean oil and diesel blends on the performance characteristics of Kirloskar single cylinder diesel engine. This study also sheds light on comparison and measurement of physical properties of diesel and test fuels i.e., the blends, and correlates them with the performance test result. It is concluded that the tested blends can be used safely and effectively in the diesel engine, at least in small blending ratios with normal Diesel fuel.
 
 
 

Effect of oxygen enrichment on CI engine behavior fueled with vegetable oil: an experimental study

The present study investigated the effect of oxygen enrichment in a CI engine on performance, emission and combustion characteristics with mahua oil (MO) as base fuel. Poor physical properties of MO, namely high viscosity and density, cause atomization problems leading to higher smoke, HC and CO emissions. The purpose of this paper is to curb smoke emissions from MO operation and to examine the possibility of direct use of straight vegetable oil in CI engine, which can mitigate CO2 emission and be cost effective. The difficulty in the mixture formation with usage of straight vegetable oil in CI engine is addressed by increasing the oxygen concentration; a separate oxygen cylinder is used to induct oxygen. The engine used for this experimentation is a twin-cylinder tractor engine that operates at a constant speed of 1500 rpm. Performance, emission and combustion parameters were determined at different loading conditions (25, 50, 75 and 100% of rated power) with varying intake-oxygen concentration from 21% (by volume) (no enrichment) to 24% (by volume) with MO and compared with diesel. Oxygen enrichment of 24% reduced smoke, HC and CO emissions by 36, 34 and 50%, respectively, at maximum load condition. The study revealed that oxygen enrichment improved the direct combustion of MO with reduced smoke, HC and CO emissions. BTE was reduced by about 5% with MO in comparison with diesel at maximum load condition. BTE was improved by 10% with 24% (by volume) with MO at maximum load in comparison with neat MO.

A novel strategy of periodic dosing of soy-lecithin as additive during long term test of diesel engine fueled with straight vegetable oil

The vegetable oil has become a frontier area of research in rural and remote areas for small or decentralized power generation applications. However, the biggest challenge in use of straight vegetable oil (SVO) in a diesel engine is the problem of injector deposits. Soy-lecithin has been identified as bio-additive to overcome the deposits problem due to its natural surfactant and emulsifying properties. Though short-term performance test using soy-lecithin as bio-additive with non-edible karanj oil showed quite good results, its effect on engine performance during long-term test needs to be experimentally investigated for its reliability. The key objective of the current work is to examine the performance of diesel engine operated with karanj oil (Pongamia pinnata) by adopting a novel strategy of periodic dosing of bio-additive during a long-term test. This study also intends to focus on lubricating oil analysis to evaluate the effectiveness of soy-lecithin as bio-additive with karanj oil. Long-term engine test was performed on a Cummins DXP, direct injection diesel genset at a constant speed and load for 130 h. A test was conducted by adopting a novel strategy of periodic dosing of bio-additive in karanj oil in a repeated cycle during engine running condition. Experimental results showed that immediately switched over to additive improved the performance of engine but its continuous use lead to degradation of engine performance. Thus, running of engine continuously with either additive or w/o additive independently would lead to degradation of the engine performance but with periodic dosing of soy-lecithin as bio-additive improved the performance of the engine. The present work suggests the strategy of running the engine with bio-additive in discreet dosages for 2 h after every 7–8 h of engine run without additive in a repeated cycle. This approach would lead to smooth running of the engine which is an improvement over the baseline performance of karanj oil either with or without soy-lecithin alone. The lubricating oil analysis revealed the normal physicochemical properties and normal wear metal level within the discarding limit after 130 h of the long run test. The information coming out of this research would be helpful to researchers working with SVO to overcome the engine problems for its long-term durability or endurance test by adding an additive in a strategic manner.

Reverse micelle formation in vegetable oil, 1-butanol and diesel biofuel blends – Elimination of need for transesterification of triglycerides

1-Butanol is a well-known biofuel for blending with both gasoline and diesel. It is also reported to act as fuel additive and convert straight vegetable oil (SVO) into a diesel blend. The direct use of SVO and 1-butanol in diesel blends has important implications for the elimination of transesterification of triglycerides. The mechanism of SVO stabilization in diesel in the presence of 1-butanol remains unknown. The present work describes the physicochemical properties and mechanism of stability of biofuel blends with 1-butanol as a fuel additive. The presence of 1-butanol as an additive results in a clear homogeneous fuel composition. The mechanisms of triglyceride stability in fuel blends with 1-butanol were studied with fluorescence techniques using the charge transfer probes Nile Red and PRODAN. We found that the micro-environment of biodiesel blends with 1-butanol results in the stabilization of triglycerides by formation of reverse micelles. The charge transfer probes displayed fluorescence emission peaks representative of the region in which they are present. We observed that the four regions present in AOT reverse micelles are also present in this 1-butanol/SVO/diesel ternary mixture. The physicochemical analysis including friccohesity has suggested that the formed reverse micelle is stable. This study is the first attempt to understand the mechanism behind stabilization of SVO as diesel blend in presence of 1-butanol.

Influence of soy-lecithin as bio-additive with straight vegetable oil on CI engine characteristics

This research has embarked on capitalizing the potential sources of domestic renewable energy. Among various alternative fuel sources for compression ignition (CI) engine, vegetable oil has gained attention in rural and remote areas for stationary decentralized power generation applications, where diesel is not easily available. However, use of straight vegetable oil (SVO) causes various issues like formation of carbon deposits, injector coking, poor atomization, cold starting, etc. This could adversely affect the engine performance and exhaust emissions. Use of an appropriate fuel additive in a fuel is an attractive option in the existing diesel engines to overcome the deposits problem and to lower airborne pollution. It is one of the simplest and easiest methods as it does not require any hardware modifications. Although a wide variety of fuel additives have been developed for diesel fuel and bio-diesel fuel or blended fuel, no special additive for SVO has been developed yet. The present study is therefore undertaken on using naturally available soy-lecithin as a bio-additive with SVO to overcome the problems related to engine performance. Soy-lecithin is well known for its surfactant and emulsifying properties. The main objective of this study is to investigate the influence of soy-lecithin with non-edible karanj oil (Pongamia pinnata) on the performance, combustion and emission characteristics of a CI engine during short term test. The optimization of dosages of soy-lecithin for karanj oil was done through critical micelle concentrations (CMC) method. This study also shed light on the influence of soy-lecithin on physical properties of karanj oil and Sauter mean diameter (SMD). The detailed structural and chemical analysis of soy-lecithin was done through GC-MS, FTIR and NMR spectroscopy. This study also focuses on the influence of soy-lecithin on injector deposits. The test was conducted on a Cummins DXP 15-5, two cylinders, DI unmodified diesel engine at a constant speed by varying brake load. The test results demonstrated that addition of soy-lecithin in karanj oil significantly reduced NOx and CO emissions as compared to karanj oil without additive with no penalty of brake specific fuel consumption. The addition of soy-lecithin in karanj oil remarkably reduced cylinder pressure, HRR, ignition delay and mean gas temperature in comparison to karanj oil without additive whereas increased mechanical efficiency throughout the load range. Soy-lecithin was found very effective in drastic reduction of injector deposits.

A comparative study on influence of fuel additives with edible and non-edible vegetable oil based on fuel characterization and engine characteristics of diesel engine

Use of vegetable oil as compression ignition engine fuel has been investigated by many researchers during last decade either by direct blending with diesel or converting it into bio-diesel but very few publications available regarding its direct use in engine. The direct use of straight vegetable oil leading to formation of injector deposits which in turn produces higher exhaust emissions. Fuel improvement through additive is an attractive option in existing diesel engine without any modification to meet worldwide legislative efforts to lower airborne pollution. Hence, use of locally available vegetable oil with addition of fuel additive in existing diesel engine becomes an indispensable tool in global trade to meet ever-tightening pollutant emissions regulations for heavy-duty diesel engine. This paper intends to compare the behaviour of edible and non-edible crude vegetable oil on engine characteristics of existing diesel engine under similar operating condition with cognitive elaboration. The main purpose of the present work was to investigate how commercially available fuel additives for diesel fuel, influence the edible and non-edible vegetable oil, by comparing the combustion, emission and performance characteristics under similar operating condition. A comparative study was carried out on Cummins two cylinder DI diesel engine at constant speed by varying brake load. The Sunflower oil (SF) was selected as edible oil and Karanj oil (KO) as non-edible oil whereas two commercially available fuel additives for diesel referred as ‘A1’ and ‘A2’ respectively in this study were procured for test trial. The experimentally obtained results revealed that both edible oil (SF) and non-edible oil (KO) showed longer ignition delay which in turn leading to higher cylinder pressure, HRR, higher NOx and CO emissions whereas showed lower BSEC and smoke opacity as compared to diesel fuel. However, the KO oil exhibited lower NOx and CO emissions when compared to SF while maintaining marginal difference in thermal efficiency. The test results showed that both additives were found effective in reduction of ignition delay, HRR and NOx formation with KO whereas increased NOx and CO emissions with SF. The additive A1 significantly reduced CO and smoke emissions with KO while the opposite trend was observed when additive A2 was used.

Performance of a Direct Injection of IC Engine on SVO and Biodiesel from Multiple Feedstocks

Straight Vegetable Oil (SVO) is a promising biofuel with a low energy input to energy output ratio. Successful use of SVO in engines depends on engine performance, wear and emissions. This study focuses on short term engine emissions and performance. This research uses oils produced in Colorado as a full diesel fuel substitute in a modified single cylinder engine. This engine testing was conducted in the laboratory. The test engine was a Yanmar TF140E, which is naturally aspirated and uses low pressure (～140 bar) mechanical direct injection. The engine fuel system was modified to accommodate a 2-tank custom SVO kit. The SVO was heated to 75 °C. Fuel economy and emissions measurements were performed for petroleum diesel, four different vegetable oils (sunflower, canola, camelina, and soybean) and their biodiesel derivatives. Fuel mass flow, oxides of nitrogen (NOX), total hydrocarbons (THC), carbon monoxide (CO), and particulate matter were measured. No engine degradation was experienced through approximately 50 hrs of testing on SVO and 50 hrs of testing on biodiesel. Overall engine emissions for SVO and biodiesel, with the exception of THC for biodiesel, were higher than petroleum diesel. More favorable biofuel emissions comparisons to diesel are expected with other engine designs based on data from various literature sources. Data comparing raw and refined SVO indicate that refined vegetable oil produces lower particulate matter (PM) emissions. General trends were observed showing that oils with higher levels of polyunsaturated fats (e.g. C18:1, C18:2, and C18:3) produce higher levels of NOX and THC’s.

Experimental Analysis of a Micro Gas Turbine Fuelled with Vegetable Oils from Energy Crops

This paper deals with the technical feasibility of the use of straight vegetable oil (SVO) as gas turbine fuels.First, this paper reports the results of the experimental characterization of different vegetable oils, derived from energy crops, and of blends of diesel and vegetable oil in different concentrations (from pure diesel to pure vegetable oil). The considered vegetable oils were obtained from different types of oilseeds (rapeseed, sunflower, soybean) and were cultivated under different agronomic scenarios. The SVO properties determined experimentally are SVO elemental composition, lower heating value, density, specific heat and viscosity, for which this paper provides a practical overview, coming both from experiments and literature data.Secondly, the paper experimentally evaluates the behavior of a Solar T-62T-32 micro gas turbine fed by vegetable oils. The vegetable oils are supplied to the micro gas turbine as blends of diesel and straight vegetable oils in different concentrations, up to pure vegetable oil. The paper describes the test rig used for the experimental activity and reports some experimental results, which highlight the effects of the different fuels on micro gas turbine performance and pollutant emissions.

Vegetable Oils of Soybean, Sunflower and Tung as Alternative Fuels for Compression Ignition Engines

This paper deals with the use of straight vegetable oil as fuel for compression ignition engine applied to distributed electric generation. It was studied three typical oils from southern of the Brazil, soybean oil, sunflower oil and tung oil. For this purpose it was designed and assembled a conversion kit that allows the use of the selected oils directly in the engine. The kit preheats the fuel to a temperature where their physical properties, mainly viscosity, reaches the diesel oil levels. This kit is electronic controlled and it was used standardized measurements of some physical properties of the fuels, for the design of their control software. The straight vegetables oils, its blends 50/50 v/v with petrodiesel fuel and neat petrodiesel fuel were tested in dynamometer bench. It was obtained results of brake power, torque, specific fuel consumption and emissions as function of the rotation of the engine. The discussions about the results in terms of efficiency first law showed the technical feasibility of the using of straight vegetable oils and the effectiveness of the developed conversion kits.

Assessing combustion and emission performance of direct use of SVO in a diesel engine by oxygen enrichment of intake air method

This work investigated the effect of the oxygen enrichment in the intake air of diesel engines on the combustion and emissions performance using rape seed oil (RSO) as a fuel. The purpose of the paper is to investigate the potential of oxygen enrichment in the intake air method to restrain the deterioration of particulate emissions of the RSO due to its high viscosity so as to explore the possibility of direct use of SVO (straight vegetable oil) in diesel engines, which can reduce CO2 emissions and save cost. The combustion parameters such as ignition delay, heat release rate, in-cylinder peak temperature and pressure were determined. Engine out particulate and gaseous emissions of the RSO were measured at oxygen concentrations from 21% (by volume) (no enrichment) to 24% (by volume) and compared to diesel results. The enrichment of the intake air with oxygen decreased the ignition delay and premixed combustion duration, and increased the in-cylinder peak pressure and temperature. The particulate, CO and hydrocarbon emissions were significantly reduced while the NOx emissions increased as the oxygen enrichment rate increased. 22% oxygen enrichment rate was suggested to achieve lower than diesel particulate emissions with the lowest NOx penalty. Increased NOx could be controlled by other methods. The results show that the oxygen enrichment in intake air method enabled direct combustion of SVO in diesel engines with reduced particulate, hydrocarbon and CO emissions.

An evaluation of the life cycle cost of rapeseed oil as a straight vegetable oil fuel to replace petroleum diesel in agriculture

The use of straight vegetable oil (SVO) as biofuel has been recognized as a valid substitute of diesel fuel in the agricultural sector under specific circumstances. Its direct use reduces most of the chemical processes involved when converting it into biodiesel, thus lowering harmful emissions. This study presents the economic analysis of a self-supply farming model that uses rapeseed as its fuel base. This model addresses agricultural environmental concerns and can even minimize dependence on the fluctuating costs of diesel fuel. The use of SVO in agriculture can help reduce farmers’ vulnerability to fossil fuel prices. The economic evaluation of the model proposed in this study shows clear economic benefits of introducing rapeseed to the traditional crop rotation of wheat and barley. The key factors analyzed in this model are diesel fuel price, diesel fuel grants and crop aids. The current situation in Spain favors the use of diesel fuel in agriculture rather than rapeseed SVO due to an 8% profit difference. However, results show that changes in key factors slightly affect the profit margin, calculating a difference of only 3.7% for particular factor combinations. Combined environmental-friendly agriculture supporting policies are necessary to cover this slight profit difference to promote this biofuel. ► We economically evaluate small-scale rapeseed oil self-supply used as biofuel. ► We model six different crop systems scenarios, two using rapeseed oil as biofuel. ► The introduction of rapeseed in the traditional crop rotation is economically advantageous. ► Scenarios using diesel fuel show slightly higher economic benefit results. ► We show that this difference can be minimized applying environmental policy measures.

Tribological Issues Related to the Use of Biofuels: A New Environmental Challenge

Due to gradual depletion of world petroleum reserves and the impact of environmental pollution of increasing exhaust emissions, there is an urgent need for suitable alternative fuels for use in engines. The heightened awareness of green house gas emissions and global warming compels introduction of more stringent environmental regulations worldwide. Renewable biofuels are considered potential solution for these problems. But use of biofuel is creating tribology related new challenges world over. In this paper a critical analysis of tribology related issue of three main biofuels, namely Straight Vegetable Oil (SVO), biodiesel and alcohols are discussed. Many issues like lubricity of blends, carbon deposit, viscosity, corrosion of engine components, etc are discussed in detail. Quality control of biofuels, identified as a key factor for sustainable market growth of these fuels and can lead to many tribological issues. In this regard a dire need for global harmonized standards is also discussed. Different solutions for alcohol fuel related engine problems are discussed. Critical discussion in relation to the problems due to the use of SVO in engine, like engine performance decrease, injector choking, oil ring sticking, etc took place in this paper. Potential solutions to these problems found by academia as well as industry are discussed here.

A proposal of electrical power supply to Brazilian Amazon remote communities

This paper focuses on supplying electrical power for remote communities of the Brazilian Amazon using regional biomass, specifically palm oil biomass, as a primary energy source. The use of Straight Vegetable Oil (SVO) as fuel, is indicated for isolated communities, where the hydro plants or the installation of transmissions line are impracticable. The use of vegetable oils produced in the communities, is a solution when an adequate infrastructure to extracting the oil is available. Brazil is able to use an enormous diversity of vegetable oils, due to a great variety of plants, and the favorable climatic conditions. Technical, economic, environmental and social aspects are analyzed in order to provide a basis for electrical power supply viability in these communities. A case study is presented focused on a typical Brazilian Amazon community located in the State of Para in order to demonstrate the applicability of the proposed viability strategy.

Performance and emission study of preheated Jatropha oil on medium capacity diesel engine

Diesel engines have proved its utility in transport, agriculture and power sector. Environmental norms and scared fossil fuel have attracted the attention to switch the energy demand to alternative energy source. Oil derived from Jatropha curcas plant has been considered as a sustainable substitute to diesel fuel. However, use of straight vegetable oil has encountered problem due to its high viscosity. The aim of present work is to reduce the viscosity of oil by heating from exhaust gases before fed to the engine, the study of effects of FIT (fuel inlet temperature) on engine performance and emissions using a dual fuel engine test rig with an appropriately designed shell and tube heat exchanger (with exhaust bypass arrangement). Heat exchanger was operated in such a way that it could give desired FIT. Results show that BTE (brake thermal efficiency) of engine was lower and BSEC (brake specific energy consumption) was higher when the engine was fueled with Jatropha oil as compared to diesel fuel. Increase in fuel inlet temperature resulted in increase of BTE and reduction in BSEC. Emissions of NO x from Jatropha oil during the experimental range were lower than diesel fuel and it increases with increase in FIT. CO (carbon monoxide), HC (hydrocarbon), CO 2 (carbon dioxide) emissions from Jatropha oil were found higher than diesel fuel. However, with increase in FIT, a downward trend was observed. Thus, by using heat exchanger preheated Jatropha oil can be a good substitute fuel for diesel engine in the near future. Optimal fuel inlet temperature was found to be 80 °C considering the BTE, BSEC and gaseous emissions.

Review of existing and emerging technologies for the production of biofuels in developing countries

The present energy crisis has reactivated worldwide the interest in biofuels, particularly in developing countries that are dependent on import of petroleum products and may have, in terms of land availability and climatic conditions, the potential for large-scale biomass production. Various routes are possible for converting biomass into transport fuel. Technologies and processes are described and fuel properties compared to those of the fuels they are supposed to substitute. Emphasis is given to the first generation biofuels, biodiesel and bioethanol, as the second-generation biofuels using whole biomass are still at an early stage of development and would require long and strong public support to be available on an industrial scale. A big consideration is biomass supply, as these resources may affect land availability and competition with food and feed production. These aspects are addressed in a separate paper. Small-scale stand-alone power generation is briefly discussed, as is the possible use of straight vegetable oil (SVO). The main barrier to the development ofbiofuel is economic. That is why cost considerations are developed. However, assessing the cost of biofuel is not easy because the feedstock biomass accounts for the largest part of the total costs and therefore the total cost depends greatly on national policy and subsidy frameworks. The paper concludes with some socio-economic considerations and discusses opportunities for implementing transport biofuel programmes in developing countries.