01 Jan 2010
TL;DR: In this paper, the combustion, performance and emission characteristics of a single cylinder diesel engine when fuelled with blends of neem and diesel oil are evaluated, and the results show that the variations in the peak pressures of all the blends at full load are marginal.
Abstract: The depletion of oil resources as well as the stringent environmental regulations has led to the development of alternate energy sources. In this work the combustion, performance and emission characteristics of a single cylinder diesel engine when fuelled with blends of neem and diesel oil are evaluated. Experiments were conducted with different blends of neem oil and diesel at various loads. The results show that the variations in the peak pressures of all the blends at full load are marginal. There is an increase in the ignition delay with biodiesel because of its high viscosity and density. It is found that the brake thermal efficiency of diesel is higher at all loads followed by blends of neem oil and diesel. The maximum brake thermal efficiency and minimum specific fuel consumption were found for blends upto B20. The specific fuel consumption, exhaust gas temperature, smoke opacity and NOx were comparatively higher. However, there is an appreciable decrease in HC and CO2 emissions while the decrease in CO emission is marginal. It was observed that the combustion characteristics of the blends of esterified neem oil with diesel followed closely with that of the base line diesel.
TL;DR: In this paper, the authors introduced some species of non-edible vegetables whose oils are potential sources of biodiesel, such as Pongamia pinnata (karanja), Calophyllum inophyllus (Polanga), Maduca indica (mahua), Hevea brasiliensis (rubber seed), Cotton seed, Simmondsia chinesnsis (Jojoba), Nicotianna tabacum (tobacco), Azadirachta indica, Linum usitatissimum (Linseed)
Abstract: Energy demand is increasing dramatically because of the fast industrial development, rising population, expanding urbanization, and economic growth in the world. To fulfill this energy demand, a large amount of fuel is widely used from different fossil resources. Burning of fossil fuels has caused serious detrimental environmental consequences. The application of biodiesel has shown a positive impact in resolving these issues. Edible vegetable oils are one of the potential feedstocks for biodiesel production. However, as the use of edible oils will jeopardize food supplies and biodiversity, non-edible vegetable oils, also known as second-generation feedstocks, are considered potential substitutes of edible food crops for biodiesel production. This paper introduces some species of non-edible vegetables whose oils are potential sources of biodiesel. These species are Pongamia pinnata (karanja), Calophyllum inophyllum (Polanga), Maduca indica (mahua), Hevea brasiliensis (rubber seed), Cotton seed, Simmondsia chinesnsis (Jojoba), Nicotianna tabacum (tobacco), Azadirachta indica (Neem), Linum usitatissimum (Linseed) and Jatropha curcas (Jatropha). Various aspects of non-edible feedstocks, such as biology, distribution, and chemistry, the biodiesel’s physicochemical properties, and its effect on engine performance and emission, are reviewed based on published articles. From the review, fuel properties are found to considerably vary depending on feedstocks. Analysis of the performance results revealed that most of the biodiesel generally give higher brake thermal efficiency and lower brake-specific fuel consumption. Emission results showed that in most cases, NOx emission is increased, and HC, CO, and PM emissions are decreases. It was reported that a diesel engine could be successfully run and could give excellent performance and the study revealed the most effective regulated emissions on the application of karanja, mahua, rubber seed, and tobacco biodiesel and their blends as fuel in a CI engine.
TL;DR: The use of non-edible resources is presently directed to jatropha, mahua, pongamia, calophyllum tobacco, cotton oil, etc.
Abstract: The demand for petroleum has risen rapidly due to increasing industrialization and modernization of the world. The limited reserve of the fossil fuels is also dwindling alongside escalation in the prices. The threats from these and food insecurity are, however, drawing the attention of researchers for alternative fuel which can be produced from renewable feedstocks. Biodiesel as the most promising alternate is currently produced from conventionally grown edible plant oils such as rapeseed, soybean, sunflower and palm. The use of the edible oils is worsening the current competition of oil for food and for fuel. Focus on the use of non-edible resources is presently directed to jatropha, mahua, pongamia, calophyllum tobacco, cotton oil, etc. Discrepancies between the expectation and realities regarding these non-edible oils are necessitating efforts for diversification of the feedstocks to resources that could guarantee energy production without affecting food security. Neem, karanja, rubber and jatropha are evergreen multipurpose non-edible plants that are widely available and can be grown in diverse socio-economic and environmental conditions. These plants are described as golden trees that have multiple uses such as for fuels, medicines, dyes, ornamentals, feeds, soil enrichment, afforestation, etc. This study was therefore undertaken to explore the multipurpose of these four non-edible tree plants. Among the highlights of this expatiate review include oil as feedstock for biodiesel, the need for non-edible feedstocks, neem, karanja, rubber, jatropha and their value chains, methods of modifying oil to biodiesel, factors affecting biodiesel production, application of the selected non-edible seed biodiesels to engines for performance and emission characteristics and the outlook.
TL;DR: In this article, the potential of different fuels as an additive in biodiesel fuel in correspond to reduce NOX emissions was reviewed and it was shown that the reduction in NOX can be achieved by the use of most fuels in blending with biodiesel under all engine operating conditions, if only the proper injection parameters and blending proportions of fuels are set.
Abstract: There are some challenges about NOX emissions exhausted from diesel engines fueled with biodiesel. Due to increasingly stringent emission regulations, the different methods such as varying the engine operating parameters, treatment with antioxidant additive and blending fuels have been adapted to reduce emissions of biodiesel combustion. One of the effective methods is the combustion of dual or blending fuels. Various fuels such as gasoline, hydrogen, natural gas, biogas, different types of alcohols and also fuel additives have been used to reduce biodiesel disadvantages. This study reviews the potential of the different fuels as an additive in biodiesel fuel in correspond to reduce NOX emissions. The general reduction of NOX has been observed with the presence of gasoline, biogas and alcohols in biodiesel blends. The reduction of NOX in biodiesel-hydrogen, biodiesel-diesel or biodiesel–CNG combustion has not been observed through all engine conditions. Moreover the retarding injection timing, the lower injection pressure, EGR higher than 30% can result in the reduced NOX emissions. However it seems the decrease in NOX emissions can be achieved by the use of most fuels in blending with biodiesel under all engine operating conditions, if only the proper injection parameters and blending proportions of fuels are set.
TL;DR: In this article, the physicochemical properties of different biodiesel blends obtained from various feedstocks with a view to properly understand the fuel quality were reviewed and a short description of each feedstock was given along with graphical presentation of important properties for various blend percentages from BO to B100.
Abstract: The growing demand for green world serves as one of the most significant challenges of modernization. Requirements like largest usage of energy for modern society as well as demand for friendly milieu create a deep concern in field of research. Biofuels are placed at the peak of the research arena for their underlying benefits as mentioned by multiple researches. Out of a number of vegetable oils, only a few are used commercially for biodiesel production. Due to various limitations of edible oil, non-edible oils are becoming a profitable choice. Till today, very little percentage of biodiesel is used successfully in engine. The research is still continuing for improving the biodiesel usage level. Recently, it is found that the blended biodiesel from more than one feedstock provides better performance in engine. This paper reviews the physicochemical properties of different biodiesel blends obtained from various feedstocks with a view to properly understand the fuel quality. Moreover, a short description of each feedstock is given along with graphical presentation of important properties for various blend percentages from BO to B100. Finally, mathematical model is formed for predicting various properties of biodiesel blend with the help of different research data by using polynomial curve fitting method. The results obtained from a number of literature based on this work shows that the heating value of biodiesel is about 11 lower than diesel except coconut (14.5 lower) whereas kinematic viscosity is in the range of 4-5.4 mm(2)/s. Flash point of all biodiesels are more than 150 degrees C, except neem and coconut. Cold flow properties of calophyllum, palm, jatropha, moringa are inferior to others. This would help to determine important properties of biodiesel blend for any percentage of biodiesel and to select the proper feedstock for better performance. (C) 2015 Elsevier Ltd. All rights reserved.
TL;DR: In this article, the current energy scenario of Bangladesh, available potential biodiesel feedstocks, production process and engine fuel property, environmental impact, performance and emission characteristics on diesel engines, comparison of cost analysis, and future direction are discussed.
Abstract: The transportation, agricultural, and power sector of Bangladesh is largely dependent on fossil fuels that decrease day by day. The government has to import large volumes of fuel from foreign sources to meet the fuel demand for power production, causing a negative impact on the country's economy. Finding an alternative to fossil fuels is becoming the most urgent issue. Biodiesel can thus be a destined source to future energy demands. Increasing the usage of biodiesel will also decrease the global problem of environmental pollution, as fossil fuels are considered to be the major source of harmful emissions. Biodiesel is renewable, bio-degradable, non-toxic, technologically feasible, and can be used as a bio-lubricant In this study, the current energy scenario of Bangladesh, available potential biodiesel feedstocks, production process and engine fuel property, environmental impact, performance and emission characteristics on diesel engines, comparison of cost analysis, and future direction are discussed. Various research related to these feedstocks are performed in Bangladesh, which include an overview of biodiesel properties, engine performance, and emission parameters used in diesel engines. All types of biodiesel have similar functional properties compared with diesel fuel and can be successfully used in compression ignition engines. Biodiesel can thus serve as a subsequent replacement of non-renewable fossil fuels. Compared with diesel fuel, CO and HC emission were also low, but a slight increase in NOx was observed in some cases. One of the major advantages is that Bangladesh is a country with plenty of biodiesel feedstock sources, such as mustered, Jatropha curcas, rapeseed, sesame, castor, cottonseed, neem, algae, coconut, and groundnut In conclusion, producing biodiesel from different feedstocks is greatly possible and can thus assist in future energy needs. (C) 2015 Elsevier Ltd. All rights reserved.