Revista Facultad De Ingenieria-universidad De Antioquia, 2010
In this paper, an experimental study evaluating engine performance, nitrogen oxide emissions (NOx... more In this paper, an experimental study evaluating engine performance, nitrogen oxide emissions (NOx) and smoke opacity of a HSDI (high speed direct injection) diesel engine fuelled with neat palm oil biodiesel (POB) is presented. Tests were performed in a bench-mounted automotive diesel engine operating under steady state conditions. Conventional diesel fuel was taken as base line or reference fuel. Results show that at full-load operation POB led to a power output decrease between 10% and 17% and an effective specific fuel consumption increase between 14% and 22%. At full-load and low engine speeds an increase of 20% in NOx emissions was measured. However, at the same torque rating and high engine speeds a 6% decrease in such emissions was obtained. At partial-load, NOx emissions always increased using POB, this effect being more pronounced at low speeds. On the other hand, smoke opacity significantly decreased (between 40% and 80%) regardless of engine load. According to the experim...
Biodiesel production from ricin oil has been the focus of several pieces of research in recent ye... more Biodiesel production from ricin oil has been the focus of several pieces of research in recent years. However, few studies related to the basic ethanolysis of this non-edible vegetable oil have been reported. In this work, the optimum conditions for maximizing the conversion of the basic ethanolysis of ricin oil were determined using the response surface methodology (RSM). Experiments were conducted using a 2k rotable central composite design. The process variables were evaluated at two levels: alcohol/oil molar ratio (3/1- 10/1), catalyst quantity (1%-1.5%), and temperature (20 oC-35 oC). In order to ensure a good adjustment of the design, a quadratic model was implemented for the response variable. The model was able to predict 99.663% of the total variation of the system. The optimum conversion was of 93.64%, obtained with an alcohol/ oil molar ratio of 9.86/1, a catalyst concentration of 1.2% with respect to oil weight, and a reaction temperature of 30 oC, for a period of 1 hour.
In this paper, an investigation to characterize the mechanical performance and emissions from a p... more In this paper, an investigation to characterize the mechanical performance and emissions from a passenger car D.I. diesel engine, fuelled with Colombian palm oil biodiesel, Colombian diesel fuel, low sulfur diesel, and blends of biodiesel according to a protocol, is presented. Experiments show an increase in vehicle autonomy between 5 and 10%. The smoke opacity diminishes between 50% and 90%, the mass of CO2 and CO diminished between 6 and 29%, depending on biodiesel concentration. The results indicate that Colombian palm oil biodiesel is an attractive energy from renewable sources, to oxygenate Colombian diesel fuel.
Differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels ... more Differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels lead to differences in their physical properties affecting the combustion process inside the engine. In this work a detailed combustion diagnosis was applied to a turbocharged automotive diesel engine operating with neat palm oil biodiesel (POB), No. 2 diesel fuel and their blends at 20 and 50% POB by volume (B20 and B50 respectively). To isolate the fuel effect, tests were executed at constant power output without carrying out any modification of the engine or its fuel injection system. As the POB content in the blend increased, there was a slight reduction in the fuel/air equivalence ratio from 0.39 (B0) to 0.37 (B100), an advance of injection timing and of start of combustion. Additionally, brake thermal efficiency, combustion duration, maximum mean temperature, temperature at exhaust valve opening and exhaust gas efficiency decreased; while the peak pressure, exergy destruction rate ...
In this paper, an experimental study focussed on the optimization of biodiesel production by tran... more In this paper, an experimental study focussed on the optimization of biodiesel production by transesterification of Colombian crude palm oil was carried out. The main variables taken into account were the molar ratio of methanol to vegetable oil (RMA) and the quantity of catalyst (CC). Using NaOH as a catalyst, a factorial experimental design 3 2 with two replies was conducted for each oil phase: olein, stearin and crude oil. The optimum conditions for achieving a maximum reaction yield were a RMA of 12 and a CC of 0.6%, using crude oil as a raw material. A good quality of biodiesel was obtained. The biofuel complies with the majority of technical specifications for diesel fuels established by international standard s.
In this work the lubricity of several ethanol (hydrated or anhydrous) / gasoline fuel blends was ... more In this work the lubricity of several ethanol (hydrated or anhydrous) / gasoline fuel blends was measured by using a conventional HFRR tester. Tests were carried out at 25oC with no water vapour pressure control, according to the ASTM D6079 standard. According to the results the range of variation of the mean wear scar diameter was small among tested fuels in the range E-20 to E-85, indicating that the addition of ethanol, anhydrous or hydrated, did not impact signifi cantly blend lubricity. The addition of hydrated ethanol (96% v/v) slightly improved blend lubricity in comparison with the addition of anhydrous ethanol. The higher mean wear scar diameters, lower fl uid fi lm traces and higher friction coeffi cients obtained for all tested fuels, in comparison with the typical values for diesel fuels, indicate the necessity of using lubricity additives when gasoline or ethanol / gasoline blends are used in new engine technologies requiring higher pressures in the fuel injection system.
The physicochemical properties of petroleum-derived jet fuels mainly depend on their chemical com... more The physicochemical properties of petroleum-derived jet fuels mainly depend on their chemical composition, which can vary from sample to sample as a result of the diversity of the crude diet processed by the refinery. Jet fuels are exposed to very low temperatures both at altitude and on the ground in places subject to extreme climates and must be able to maintain their fluidity at these low temperatures otherwise the flow of fuel to turbine engines will be reduced or even stopped. In this work, an experimental evaluation of the effect of chemical composition on low-temperature fluidity properties of jet fuels (freezing point, crystallization onset temperature and viscosity at −20 °C) was carried out. Initially, a methodology based on gas chromatography coupled to mass spectrometry (GC–MS) was adapted to determine the composition of 70 samples of Jet A1 and Jet A fuels. This methodology allowed quantifying the content, in weight percentage, of five main families of hydrocarbons: par...
The faulty performance of palm oil biodiesel at low temperatures constitutes its main quality dra... more The faulty performance of palm oil biodiesel at low temperatures constitutes its main quality drawback and limitation to use this alternative fuel for diesel engines either as a neat fuel or blended with conventional diesel fuel derived from petroleum. In this work, several alternatives for improving the cold fl ow properties of palm oil biodiesel are evaluated. The production of biodiesel using branched-chain alcohols such as isopropyl alcohol, isobutyl alcohol, 2-butyl alcohol and isopentyl alcohol allows the production of palm oil alkyl esters having cloud and pour points lower than those of methyl esters. Substituting isopropyl for the methyl group allows reductions in the cloud and pour points of 8 and 21 oC, respectively. Palm oil isopropyl esters have a cloud point 10 oC lower than the corresponding methyl esters. The cloud point of the palm oil biodieseldiesel fuel blends linearly increases with mixture biodiesel content. In the case of the tested blends there may be fuel fi...
En este articulo se presenta un estudio experimental sobre la produccion y utilizacion del biodie... more En este articulo se presenta un estudio experimental sobre la produccion y utilizacion del biodiesel de aceite de higuerilla. El maximo rendimiento de metilesteres en la reaccion de transesterificacion del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relacion molar metanol/aceite de 9 y una concentracion de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petroleo en proporciones hasta del 15%, sin que la mezcla resultante se salga de las especificaciones de calidad estipuladas en los estandares nacionales e internacionales para combustibles diesel. La mayor dificultad para el uso del biodiesel de aceite de higuerilla en motores es su alta viscosidad. Sin embargo este biocombustible presenta excelentes propiedades de flujo a baja temperatura (valores bajos para los puntos de nube y fluidez). Las pruebas en motor con mezclas biodiesel de higuerilla/diese...
Revista Facultad De Ingenieria-universidad De Antioquia, 2010
In this paper, an experimental study evaluating engine performance, nitrogen oxide emissions (NOx... more In this paper, an experimental study evaluating engine performance, nitrogen oxide emissions (NOx) and smoke opacity of a HSDI (high speed direct injection) diesel engine fuelled with neat palm oil biodiesel (POB) is presented. Tests were performed in a bench-mounted automotive diesel engine operating under steady state conditions. Conventional diesel fuel was taken as base line or reference fuel. Results show that at full-load operation POB led to a power output decrease between 10% and 17% and an effective specific fuel consumption increase between 14% and 22%. At full-load and low engine speeds an increase of 20% in NOx emissions was measured. However, at the same torque rating and high engine speeds a 6% decrease in such emissions was obtained. At partial-load, NOx emissions always increased using POB, this effect being more pronounced at low speeds. On the other hand, smoke opacity significantly decreased (between 40% and 80%) regardless of engine load. According to the experim...
Biodiesel production from ricin oil has been the focus of several pieces of research in recent ye... more Biodiesel production from ricin oil has been the focus of several pieces of research in recent years. However, few studies related to the basic ethanolysis of this non-edible vegetable oil have been reported. In this work, the optimum conditions for maximizing the conversion of the basic ethanolysis of ricin oil were determined using the response surface methodology (RSM). Experiments were conducted using a 2k rotable central composite design. The process variables were evaluated at two levels: alcohol/oil molar ratio (3/1- 10/1), catalyst quantity (1%-1.5%), and temperature (20 oC-35 oC). In order to ensure a good adjustment of the design, a quadratic model was implemented for the response variable. The model was able to predict 99.663% of the total variation of the system. The optimum conversion was of 93.64%, obtained with an alcohol/ oil molar ratio of 9.86/1, a catalyst concentration of 1.2% with respect to oil weight, and a reaction temperature of 30 oC, for a period of 1 hour.
In this paper, an investigation to characterize the mechanical performance and emissions from a p... more In this paper, an investigation to characterize the mechanical performance and emissions from a passenger car D.I. diesel engine, fuelled with Colombian palm oil biodiesel, Colombian diesel fuel, low sulfur diesel, and blends of biodiesel according to a protocol, is presented. Experiments show an increase in vehicle autonomy between 5 and 10%. The smoke opacity diminishes between 50% and 90%, the mass of CO2 and CO diminished between 6 and 29%, depending on biodiesel concentration. The results indicate that Colombian palm oil biodiesel is an attractive energy from renewable sources, to oxygenate Colombian diesel fuel.
Differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels ... more Differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels lead to differences in their physical properties affecting the combustion process inside the engine. In this work a detailed combustion diagnosis was applied to a turbocharged automotive diesel engine operating with neat palm oil biodiesel (POB), No. 2 diesel fuel and their blends at 20 and 50% POB by volume (B20 and B50 respectively). To isolate the fuel effect, tests were executed at constant power output without carrying out any modification of the engine or its fuel injection system. As the POB content in the blend increased, there was a slight reduction in the fuel/air equivalence ratio from 0.39 (B0) to 0.37 (B100), an advance of injection timing and of start of combustion. Additionally, brake thermal efficiency, combustion duration, maximum mean temperature, temperature at exhaust valve opening and exhaust gas efficiency decreased; while the peak pressure, exergy destruction rate ...
In this paper, an experimental study focussed on the optimization of biodiesel production by tran... more In this paper, an experimental study focussed on the optimization of biodiesel production by transesterification of Colombian crude palm oil was carried out. The main variables taken into account were the molar ratio of methanol to vegetable oil (RMA) and the quantity of catalyst (CC). Using NaOH as a catalyst, a factorial experimental design 3 2 with two replies was conducted for each oil phase: olein, stearin and crude oil. The optimum conditions for achieving a maximum reaction yield were a RMA of 12 and a CC of 0.6%, using crude oil as a raw material. A good quality of biodiesel was obtained. The biofuel complies with the majority of technical specifications for diesel fuels established by international standard s.
In this work the lubricity of several ethanol (hydrated or anhydrous) / gasoline fuel blends was ... more In this work the lubricity of several ethanol (hydrated or anhydrous) / gasoline fuel blends was measured by using a conventional HFRR tester. Tests were carried out at 25oC with no water vapour pressure control, according to the ASTM D6079 standard. According to the results the range of variation of the mean wear scar diameter was small among tested fuels in the range E-20 to E-85, indicating that the addition of ethanol, anhydrous or hydrated, did not impact signifi cantly blend lubricity. The addition of hydrated ethanol (96% v/v) slightly improved blend lubricity in comparison with the addition of anhydrous ethanol. The higher mean wear scar diameters, lower fl uid fi lm traces and higher friction coeffi cients obtained for all tested fuels, in comparison with the typical values for diesel fuels, indicate the necessity of using lubricity additives when gasoline or ethanol / gasoline blends are used in new engine technologies requiring higher pressures in the fuel injection system.
The physicochemical properties of petroleum-derived jet fuels mainly depend on their chemical com... more The physicochemical properties of petroleum-derived jet fuels mainly depend on their chemical composition, which can vary from sample to sample as a result of the diversity of the crude diet processed by the refinery. Jet fuels are exposed to very low temperatures both at altitude and on the ground in places subject to extreme climates and must be able to maintain their fluidity at these low temperatures otherwise the flow of fuel to turbine engines will be reduced or even stopped. In this work, an experimental evaluation of the effect of chemical composition on low-temperature fluidity properties of jet fuels (freezing point, crystallization onset temperature and viscosity at −20 °C) was carried out. Initially, a methodology based on gas chromatography coupled to mass spectrometry (GC–MS) was adapted to determine the composition of 70 samples of Jet A1 and Jet A fuels. This methodology allowed quantifying the content, in weight percentage, of five main families of hydrocarbons: par...
The faulty performance of palm oil biodiesel at low temperatures constitutes its main quality dra... more The faulty performance of palm oil biodiesel at low temperatures constitutes its main quality drawback and limitation to use this alternative fuel for diesel engines either as a neat fuel or blended with conventional diesel fuel derived from petroleum. In this work, several alternatives for improving the cold fl ow properties of palm oil biodiesel are evaluated. The production of biodiesel using branched-chain alcohols such as isopropyl alcohol, isobutyl alcohol, 2-butyl alcohol and isopentyl alcohol allows the production of palm oil alkyl esters having cloud and pour points lower than those of methyl esters. Substituting isopropyl for the methyl group allows reductions in the cloud and pour points of 8 and 21 oC, respectively. Palm oil isopropyl esters have a cloud point 10 oC lower than the corresponding methyl esters. The cloud point of the palm oil biodieseldiesel fuel blends linearly increases with mixture biodiesel content. In the case of the tested blends there may be fuel fi...
En este articulo se presenta un estudio experimental sobre la produccion y utilizacion del biodie... more En este articulo se presenta un estudio experimental sobre la produccion y utilizacion del biodiesel de aceite de higuerilla. El maximo rendimiento de metilesteres en la reaccion de transesterificacion del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relacion molar metanol/aceite de 9 y una concentracion de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petroleo en proporciones hasta del 15%, sin que la mezcla resultante se salga de las especificaciones de calidad estipuladas en los estandares nacionales e internacionales para combustibles diesel. La mayor dificultad para el uso del biodiesel de aceite de higuerilla en motores es su alta viscosidad. Sin embargo este biocombustible presenta excelentes propiedades de flujo a baja temperatura (valores bajos para los puntos de nube y fluidez). Las pruebas en motor con mezclas biodiesel de higuerilla/diese...
Uploads
Papers by PEDRO BENJUMEA