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1.
The increasing energy demands along with the expected depletion of fossil fuels have promoted to search for alternative fuels that can be obtained from renewable energy resources. Biodiesel as a renewable energy resource has drawn the attention of many researchers and scientists because its immense potential to be part of a sustainable energy mix in near future.This report attempts to compile the findings on current global and Malaysian energy scenario, potential of biodiesel as a renewable energy source, biodiesel policies and standards, practicability of Jatropha curcas as a biodiesel source in Malaysia as well as impact of biodiesel from Jatropha curcas. Final part of this report also describes the development of biodiesel market in Malaysia.The paper found that Jatropha curcas is one of the cheapest biodiesel feedstock and it possesses the amicable fuel properties with higher oil contents compared to others. Being non edible oil seed feedstocks it will not affect food price and spur the food versus fuel dispute. Jatropha can be substituted significantly for oil imports. Jatropha biodiesel has potential to reduce GHG emission than diesel fuel and it can be used in diesel engine with similar performance of diesel fuel. Jatropha curcas has an immense contribution to develop rural livelihoods too. Finally biodiesel production from Jatropha is eco-friendly and offers many social and economical benefits for Malaysia and can play an increasingly significant role to fulfill the energy demand in Malaysia.  相似文献   

2.
Prospects of biodiesel production from microalgae in India   总被引:3,自引:0,他引:3  
Energy is essential and vital for development, and the global economy literally runs on energy. The use of fossil fuels as energy is now widely accepted as unsustainable due to depleting resources and also due to the accumulation of greenhouse gases in the environment. Renewable and carbon neutral biodiesel are necessary for environmental and economic sustainability. Biodiesel demand is constantly increasing as the reservoir of fossil fuel are depleting. Unfortunately biodiesel produced from oil crop, waste cooking oil and animal fats are not able to replace fossil fuel. The viability of the first generation biofuels production is however questionable because of the conflict with food supply. Production of biodiesel using microalgae biomass appears to be a viable alternative. The oil productivity of many microalgae exceeds the best producing oil crops. Microalgae are photosynthetic microorganisms which convert sunlight, water and CO2 to sugars, from which macromolecules, such as lipids and triacylglycerols (TAGs) can be obtained. These TAGs are the promising and sustainable feedstock for biodiesel production. Microalgal biorefinery approach can be used to reduce the cost of making microalgal biodiesel. Microalgal-based carbon sequestration technologies cover the cost of carbon capture and sequestration. The present paper is an attempt to review the potential of microalgal biodiesel in comparison to the agricultural crops and its prospects in India.  相似文献   

3.
Jatropha, a non-edible oil seed yielding plant has been identified by the Government of India to produce biodiesel under National Biodiesel Mission. Failure of National Biodiesel Mission Phase-I requires critical analysis of all the possible facts related to its long-term sustainability. Present work identifies important sustainability issues related to promotion of Jatropha biodiesel in India. These sustainability issues have been regrouped in four major categories: technological, environmental, economic and social. This paper attempts to explore various sustainability issues taking into account the recent Indian experiences with possible government support/initiatives for successful adoption of Jatropha biodiesel in Indian scenario.  相似文献   

4.
In the current scenario of depleting energy resources, increasing food insecurity and global warming, Jatropha has emerged as a promising energy crop for India. The aim of this study is to examine the life cycle energy balance for Jatropha biodiesel production and greenhouse gas emissions from post-energy use and end combustion of biodiesel, over a period of 5 years. It’s a case specific study for a small scale, high input Jatropha biodiesel system. Most of the existing studies have considered low input Jatropha biodiesel system and have used NEB (Net energy balance i.e. difference of energy output and energy input) and NER (Net energy ratio i.e. ratio of energy output to energy input) as indicators for estimating the viability of the systems. Although, many of them have shown these indicators to be positive, yet the values are very less. The results of this study, when compared with two previous studies of Jatropha, show that the values for these indicators can be increased to a much greater extent, if we use a high input Jatropha biodiesel system. Further, when compared to a study done on palm oil and Coconut oil, it was found even if the NEB and NER of biodiesel from Jatropha were lesser in comparison to those of Palm oil and Coconut oil, yet, when energy content of the co-products were also considered, Jatropha had the highest value for both the indicators in comparison to the rest two.  相似文献   

5.
The world today is faced with serious global warming and environmental pollution. Besides, fossil fuel will become rare and faces serious shortage in the near future. This has triggered the awareness to find alternative energy as their sustainable energy sources. Biodiesel as a cleaner renewable fuel has been considered as the best substitution for diesel fuel due to it being used in any compression ignition engine without any modification. The main advantages of using biodiesel are its renewability and better quality of exhaust gas emissions. This paper reviews the production, performance and emission of palm oil, Jatropha curcas and Calophyllum inophyllum biodiesel. Palm oil is one of the most efficient oil bearing crops in terms of oil yield, land utilization, efficiency and productivity. However, competition between edible oil sources as food with fuel makes edible oil not an ideal feedstock for biodiesel production. Therefore, attention is shifted to non-edible oil like Jatropha curcas and Calophyllum inophyllum. Calophyllum inophyllum oil can be transesterified and being considered as a potential biodiesel fuel. Compared to Palm oil and Jatropha biodiesel industry, biodiesel from Calophyllum inophyllum is still in a nascent state. Therefore, long term endurance research and tribological studies need to be carried out before Calophyllum inophyllum oil base biodiesel can become an alternative fuel in future.  相似文献   

6.
The present study deals with the development of a biodiesel production reactor based on pressurized ultrasonic cavitation technique. Transesterification of Jatropha oil takes place by passing low-frequency ultrasonic irradiation in the reaction mixture flowing at pressurized conditions in the sonochemical reactor. Reaction variables such as reaction time, molar ratio, catalyst concentration, and pressure of the reaction mixture were investigated to find the optimal parameters for biodiesel production. The energy requirement decreases with increase in pressure. Very low value of Specific Energy Consumption (0.018 kWh/kg) and significantly high value of Energy Use Index (598.83) are obtained when the pressure of reaction mixture is 15 bar. Increasing the pressure thereafter, leads to nominal gains. Ultrasonic irradiation at high-pressure condition has an additional advantage of rapid reaction and lower requirement of alcohol to oil molar ratio and catalyst concentration. Fifteen bar pressure is optimal for biodiesel production.  相似文献   

7.
This study involved a comparative experimental characterization of trace metals and relative toxicity evaluation of particulates emitted by a medium-duty transportation diesel engine using diesel and 20% (v/v) Jatropha biodiesel blend (B20). The engine was operated at 1800 rpm and particulate samples were collected on a filter paper at five loads (0%, 25%, 50%, 75% and 100% rated load) at steady state using a partial flow dilution tunnel, for both diesel and B20. Samples were then analyzed for trace metals, particulate morphology, total organic carbon and benzene soluble organic fraction (BSOF), which is a marker of toxicity. Concentrations of crust elements (Al, Ca, Fe and Mg) in the particulates were relatively higher than that of anthropogenic elements (Cd, Cr, Cu, and Zn) for both test fuels. B20 emitted relatively lower trace metal concentrations in particulates compared to baseline mineral diesel and these concentrations decreased with increasing engine load. Concentrations of gaseous emissions namely CO and THC in biodiesel exhaust were relatively lower than mineral diesel however NOx was relatively higher. Scanning electron microscopy of the particulate samples collected on the filter papers was done along with EDAX analysis for comparison.  相似文献   

8.
The aim of this research is to identify and quantify the categories which have the largest environmental impact in the biodiesel production process from Jatropha curcas L oil. The Jatropha curcas L is selected due to its availability in Cuba, so 400 L/d was defined as a functional unit. The valorization analysis was conducted taking into account the conventional Jatropha curcas L oil production. The analysis is conducted based on several factors such as the use of synthetic fertilizers, pesticides, and agriculture wastes. The activities of agriculture and industrial stages are shown. The Life Cycle Assessment is addressed according to the ISO 14040 series, by using the Ecoinvent database 2003 and the Eco-indicator 99 methodology. Based on the obtained results, the environmental performance of the production of biodiesel from Jatropha curcas L oil has a good environmental behavior. The agriculture stage shows the greatest impact due to land use and fossil fuel depletion. In addition, electricity has the highest impact due to respiratory effects from the emission of tiny material particles into the atmosphere.  相似文献   

9.
Biodiesel has the potential to significantly contribute to making transportation fuels more sustainable. Due to the complexity and nonlinearity of processes for biodiesel production and use, fast and accurate modeling tools are required for their design, optimization, monitoring, and control. Data-driven machine learning (ML) techniques have demonstrated superior predictive capability compared to conventional methods for modeling such highly complex processes. Among the available ML techniques, the artificial neural network (ANN) technology is the most widely used approach in biodiesel research. The ANN approach is a computational learning method that mimics the human brain's neurological processing ability to map input-output relationships of ill-defined systems. Given its high generalization capacity, ANN has gained popularity in dealing with complex nonlinear real-world engineering and scientific problems. This paper is devoted to thoroughly reviewing and critically discussing various ML technology applications, with a particular focus on ANN, to solve function approximation, optimization, monitoring, and control problems in biodiesel research. Moreover, the advantages and disadvantages of using ML technology in biodiesel research are highlighted to direct future R&D efforts in this domain. ML technology has generally been used in biodiesel research for modeling (trans)esterification processes, physico-chemical characteristics of biodiesel, and biodiesel-fueled internal combustion engines. The primary purpose of introducing ML technology to the biodiesel industry has been to monitor and control biodiesel systems in real-time; however, these issues have rarely been explored in the literature. Therefore, future studies appear to be directed towards the use of ML techniques for real-time process monitoring and control of biodiesel systems to enhance production efficiency, economic viability, and environmental sustainability.  相似文献   

10.
小桐油制备生物柴油的研究   总被引:12,自引:1,他引:11  
实验研究了以小桐子油为原料,采用循环气相酯化-酯交换-水蒸气蒸馏法制备生物柴油的工艺过程。着重研究了降低原料酸值以及酯交换过程的优化条件。试验结果表明。气相酯化法可在很短的时间内将原料的酸值降到酯交换对原料的酸值要求;酯交换反应的最佳操作条件为:甲醇用量为油重的20%,催化剂用量为油重的1%左右,反应温度为60—70℃,反应时间为90—120min。  相似文献   

11.
Biodiesel consists of long chain fatty acid esters derived from feed stocks such as vegetable oils, animal fats and used frying oil, etc. which may contain more or less unsaturated fatty acids which are prone to oxidation accelerated by exposure to air during storage and at high temperature may yield polymerized compounds. Auto oxidation of biodiesel can cause degradation of fuel quality by affecting the stability parameters. Biodiesel stability includes oxidation, storage and thermal stability. Oxidation instability can led to the formation of oxidation products like aldehydes, alcohols, shorter chain carboxylic acids, insolubles, gum and sediment in the biodiesel. Thermal instability is concerned with the increased rate of oxidation at higher temperature which in turn, increases the weight of oil and fat due to the formation of insolubles. Storage stability is the ability of liquid fuel to resist change in its physical and chemical characteristics brought about by its interaction with its environment and may be affected by interaction with contaminants, light, factors causing sediment formation, changes in color and other changes that reduce the clarity of the fuel. These fuel instabilities give rise to formation of undesirable substances in biodiesel and its blends beyond acceptable quantities as per specifications and when such fuel is used in engine, it impairs the engine performance due to fuel filter plugging, injector fouling, deposit formation in engine combustion chamber and various components of the fuel system.The present review attempts to cover the different types of fuel stabilities, mechanism of occurrence and correlations/equations developed to investigate the impact of various stability parameters on the stability of the fuel. A review of the use of different types of natural and synthetic antioxidants has also been presented which indicates that natural antioxidants, being very sensitive to biodiesel production techniques and the distillation processes have varying impacts on fuel stability and available literature is very much scarce. The work on the use of synthetic antioxidants on the stability of biodiesel (both distilled and undistilled) from various resources has indicated that out of various 8 synthetic antioxidants studied so far only 3 antioxidants have been found to increase the fuel stability significantly. However, effectiveness of these antioxidants is in the order of TBHQ > PY > PG.  相似文献   

12.
According to proposed National Mission on biodiesel in India, we have undertaken studies on stability of biodiesel from tree borne non-edible oil seeds Jatropha. European biodiesel standard EN-14214 calls for determining oxidation stability at 110 °C with a minimum induction time of 6 h by the Rancimat method (EN-14112). Neat Jatropha biodiesel (JBD) exhibited oxidation stability of 3.95 h and research was conducted to investigate influence of presence of transition metals, likely to be present in the metallurgy of storage tanks and barrels, on oxidation stability of Jatropha methyl ester. It was found that influence of metal was detrimental to oxidation stability and catalytic. Even small concentrations of metal contaminants showed nearly same influence on oxidation stability as large amounts. Copper showed strongest detrimental and catalytic effect. The dependence of the oxidation stability on the type of metal showed that long-term storage tests in different types of metal containers for examining the influence of container material on oxidation stability of biodiesel may be replaced by significantly faster Rancimat test serving as an accelerated storage test.  相似文献   

13.
In this work two genus of the Jatropha family: the Jatropha gossypiifolia (JG) and Jatropha curcas L. (JC) were studied in order to delimitate their potential as raw material for biodiesel production. The oil content in wild seeds and some physical–chemical properties of the oils and the biodiesel obtained from them were evaluated. The studied physical–chemical properties of the JC and JG biodiesel are in acceptable range for use as biodiesel in diesel engines, showing a promising economic exploitation of these raw materials in semi-arid regions. However, further agronomic studies are needed in order to improve the seed production and the crude oil properties.  相似文献   

14.
Energy is the most important necessity for human existence on the earth. Limited crude petroleum resources and increasing awareness regarding the environmental impacts of fossil fuels are driving the search for new energy sources and alternative fuels. Biodiesel is a fuel which is renewable, biodegradable, environmentally friendly, and non-toxic in nature and has attracted considerable attention during the past decades. The costs of feedstock and the production process are two major hurdles to large-scale biodiesel production in particular. Various technologies have been developed to reduce the production cost. This paper attempts to extensively review microwave-assisted technology for biodiesel production. Additionally, different types of feedstocks for biodiesel production have been summarized in this paper. It is concluded that the microwave-assisted technique reduces the reaction time significantly in comparison with conventional methods. In addition, a high quality biodiesel can be obtained from microwave-assisted transesterification of different kinds of oils. Finally, the energy payback for 1kg biodiesel produced by microwave-assisted technology is calculated in this paper and it indicated that the system is sustainable. Therefore it can be a suitable method of decreasing the cost of biodiesel and can also help the commercialization of this fuel.  相似文献   

15.
16.
This paper proposes a methodology for thermodynamic model analysis of Jatropha biodiesel engine in combination with Taguchi’s optimization approach to determine the optimum engine design and operating parameters. A thermodynamic model based on two-zone Weibe’s heat release function has been employed to simulate the Jatropha biodiesel engine performance. Among the important engine design and operating parameters 10 critical parameters were selected assuming interactions between the pair of parameters. Using linear graph theory and Taguchi method an L16 orthogonal array has been utilized to determine the engine test trials layout. In order to maximize the performance of Jatropha biodiesel engine the signal to noise ratio (SNR) related to higher-the-better (HTB) quality characteristics has been used. The present methodology correctly predicted the compression ratio, Weibe’s heat release constants and combustion zone duration as the critical parameters that affect the performance of the engine compared to other parameters.  相似文献   

17.
The environmental benefits and energy savings of the production of Jatropha fuels and operation in a typical LPV in India were examined. A baseline scenario and alternative optimised routes were assessed, considering different pathways of energy recovery from Jatropha coproducts. The following impact categories were assessed: Non-Renewable Energy (NRE) consumption, Global Warming Potential (GWP), Terrestrial Acidification Potential (TAP) and Respiratory Inorganic Effects (RIE). At present, the life cycle impact of Jatropha production and use is competitive with conventional diesel in terms of NRE and GHG emissions; however it results in higher local environmental impacts (RIE and TAP categories). Under optimised farming and processing practices and recovery of Jatropha coproducts either via co-generation, gasification or FT-diesel synthesis routes, Jatropha fuels reduce the impact of NRE, GHG, and RIE. The energy recovery paths to generate surplus electricity through generation and gasification routes show a better performance than FT-diesel synthesis routes in terms of NRE and GWP impacts. Nevertheless, in terms of local air pollution indicators, the FT-diesel synthesis route reveals the lowest emissions.  相似文献   

18.
Biodiesel production is profitable only under special conditions. Technical challenges including methods to make the transesterification reaction more energy efficient and faster by using catalysts, controlling reaction conditions more efficiently in narrow range, or selection of appropriate feedstocks should be properly addressed to make biodiesel economical viable fuel. Cradle to grave assessment of biodiesel is provided in the present review article. Transesterification reaction variables that affect the purity and performance of biodiesel including quality of raw materials, molar ratio of alcohol to oil, type and concentration of used catalysts, concentration of free fatty acids, water content, temperature, and time required for the reaction are critically described to provide complete understanding and obtaining economical and optimal biodiesel yields. This article also provides a critical review of biodiesel properties such as density, viscosity, cetane number, cloud point, pour point, and flash point. The importance of analytical methods including gas chromatography, high‐performance liquid chromatography, nuclear magnetic resonance spectroscopy, infrared spectroscopy, and Raman spectroscopy is presented and highlighted here in a novel way. Finally, this review will provide complete understanding to readers about biodiesel.  相似文献   

19.
In the present work, the oxidation stabilities of oil biodiesel fuel from Jatropha curcas L were investigated by using both Rancimat and PetroOXY test method. Three types of conventional antioxidants, i.e. butylated hydroxytoluene, 6,6-di-tert-butyl-2,2-methylenedi-p-cresol, and commercialized amine, were employed and the oxidation stability effects of those additives were examined. Oxidation stability was influenced differently depending on the type of antioxidants and their concentrations. The obtained experimental data from Rancimat and PetroOXY test methods resulting in a linear correlation at various mixtures shows the potential use of PetroOXY test method for future analytical oxidation stability test. In this research, the changes in the chemical properties of fuel sample, such as: peroxide value, acid value, composition, and kinematic viscosity, obtained from the experimental work were thoroughly discussed.  相似文献   

20.
This work compared the production of biodiesel from two different non-edible oils with relatively high acid values (Jatropha oil and Krating oil). Using non-catalytic supercritical methanol transesterification, high methyl ester yield (85–90%) can be obtained in a very short time (5–10 min). However, the dependence of fatty acid methyl ester yield on reaction conditions (i.e., temperature and pressure) and the optimum conditions were different by the source of oils and were correlated to the amount of free fatty acids (FFAs) and unsaturated fatty acid content in oils. Krating oil, which has higher FFAs and unsaturated fatty acid content, gave higher fatty acid methyl ester yield of 90.4% at 260 °C, 16 MPa, and 10 min whereas biodiesel from Jatropha oil gave fatty acid methyl ester yield of 84.6% at 320 °C, 15 MPa and 5 min using the same molar ratio of methanol to oil 40:1. The product quality from crude Krating oil met the biodiesel standard. Pre-processing steps such as degumming or oil purification are not necessary.  相似文献   

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