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1.
Biofuels could reduce reliance on fossil oil, while helping to reduce greenhouse gas emissions and promoting rural development. This study assessed the viability of using local biodiesel production from sunflower in Tuscany (Italy) to meet inland demand for diesel fuel in compliance with the European Directives. A crop growth model, GIS and geostatistics were used to identify suitable areas for biodiesel production, considering potential sunflower yields alongside essential sustainability criteria: energy efficiency and greenhouse gas (GHG) savings throughout the supply chain. Simulation results indicate that biodiesel potential, estimated at 95,000 t/year, corresponds to 104,400 tCO2 eq/year of GHG saved and to 26,500 TOE/year of fossil energy saved. Two scenarios of biodiesel requirement, derived from EU targets, were evaluated. The results of the evaluation indicated that the 2010 target of replacing 5.75% of transportation diesel fuel can be met, while the 2020 target (reaching a 10% of replacement) cannot be met, since local biodiesel production could replace only 4.78% of diesel fuel requirement. A third scenario considered replacing diesel fuel currently used in the agricultural sector. Results showed that the fuel requirement of this sector cannot be fulfilled since biodiesel could cover only approximately 36% of the expected demand.  相似文献   

2.
Depleting fossil fuel sources accompanied by continuously growing energy demands lead to increased interest in alternative energy sources. Blended biodiesel–diesel fuel has been approved as a commercial fuel at a low blending ratio. However, problems related to fuel properties are persistent at high blending ratios. Hence, in this study, the feasibility of biodiesel produced from palm oil was investigated. Characterization of blended fuel properties with increasing palm biodiesel ratio is conducted to evaluate engine performance test results. The qualifying of blended fuel properties was used to indicate the maximum blending ratio suitable for use in unmodified diesel engines according to the blended fuel standard ASTM D7467. The property test results revealed that blended fuel properties meet blended fuel standard requirements at up to 30% palm oil biodiesel. Furthermore, blending is efficient for reduction of the pour point from 14 °C for unblended biodiesel to less than 0 °C at a 30% biodiesel blending ratio. However, the energy content reduces by about 1.42% for each 10% increment of biodiesel. Engine test results demonstrated that there was no statistically significant difference for engine brake thermal efficiency among tested blended fuels compared to mineral diesel, and the lowest engine cyclic variation was achieved with blended fuel B30.  相似文献   

3.
Faced with the energy crisis and environmental degradation, due to the massive use of fossil energy sources, biodiesel is an attractive alternative to diesel fuel. With a view to developing local biodiesel production, using bioethanol as a sustainable reactant for biodiesel production, rather than methanol, is leading to increasing interest, notably in emerging countries. Indeed, bioethanol, which is less toxic than methanol, is produced from local and renewable agricultural resources, being more sustainable and providing access to greater energy independence. However, some issues are limiting the process like purification problems, or the presence of water in bioethanol leading to a drop in yield. Although several studies have already been published on ethyl ester production, most of them primarily focus on homogeneous alkaline catalysis, and report various data. Therefore, this paper aims at presenting a review of previous studies on the subject.  相似文献   

4.
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   

5.
In recent decades, the energy crisis and environmental issues have become a crucial problem. The rapid industrialization has lead humankind to deplete the fossil fuels and consequently the pollutant emissions have increased in the world. Many investigations have been done to find an alternative fuel to fulfill increasing energy demand. Recently, biodiesel has been introduced as an economical renewable and sustainable fuel which is cited as an environment-friendly resource. Around 350 oil-bearing crops were analyzed and some of them were capable to be considered as potential alternative fuels for diesel engines. These include virgin vegetable oils and waste vegetable oils. Rapeseed, jatropha, soybean, and palm oil are mentioned as the most common sources of biodiesel. Many countries have invested in biodiesel as an acceptable source of energy not only in research area but also in production and export. It has been proven that the biodiesel combustion characteristics are similar as petroleum. Higher ignition pressure and temperature, shorter ignition delay and higher peak release were reported in experimental combustion of biodiesel blends. Also, the efficiency of biodiesel base catalysts is more than enzymes and acid catalysts. This article is a literature review on necessity of biodiesel production as alternative fuel recourse in Malaysia and tries to illustrate the combustion characteristics and pollutant formation in biodiesel application.  相似文献   

6.
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   

7.
For a developing nation like India, the current energy portfolio is dominated by fossil fuels such as oil, coal, and petroleum products. Due to the rapid depletion and limited available resources, the price of fossil fuel increases. Also, fossil fuel induces climate change, environmental pollution, and rising global temperature. There is urgent need to shift from conventional energy to renewable energy source for sustainable and economic growth and to enhance a country’s energy security. Biofuel offers an attractive source of energy for the substitution of fossil fuels, and looking at the huge demand for diesel in all sectors of the economy, the biodiesel is being viewed as the best substitute for diesel. The other advantage for biofuel promotion in India is climate change mitigation through reduced greenhouse gas (GHG) emission. This article provides the current status of biodiesel development in India and discusses the role played by the centre and state government in promoting second-generation feedstock (nonedible seeds) and third-generation feedstock (algae) for biodiesel production.  相似文献   

8.
近年来,生物柴油作为一种无毒的、可生物降解的、可再生的柴油机代用燃料倍受关注.但在选用其作为汽车代用燃料时,必须对其做出科学、客观的评估.为了能够正确评价生物柴油的能耗与排放,利用GREET1.7软件对柴油、大豆油甲酯和大豆油甲酯-柴油混合液的能耗和排放进行生命周期评价.研究结果表明,与柴油相比,随着掺混比的增大,能耗总量增大,化石燃料消耗减小,C02和GHGs排放降低,VOC、CO、NOxC02颗粒(PM 10和PM2.5)和SOx排放均升高.  相似文献   

9.
The continuous increasing demand for energy and the diminishing tendency of petroleum resources has led to the search for alternative renewable and sustainable fuel. Biodiesel is best substitute for petro-diesel and also most advantageous over petro-diesel for its environmental friendliness. The quality of biodiesel fuel was found to be significant for its successful use on compression ignition engines and subsequent replacement of non-renewable fossil fuels. Conventional biodiesel separation and purification technologies were noticed to yield lower quality biodiesel fuel with resultant excessive energy and water consumptions. Membrane technology showed more potential for effective and efficient separation and purification of biodiesel. This technology need be explored for the attainment of better quality biodiesel fuels. This paper reviews the technologies used for the biodiesel separation and purification, biodiesel quality, and its effects on diesel engines. Biodiesel biodegradability, lubricity, stability, economic importance, and gaseous emissions have been discussed.  相似文献   

10.
ABSTRACT

For fetching day-to-day energy needs, current energy requirement majorly depends on fossil fuels. But ambiguous matter like abating petroleum products and expanding air pollution has enforced the experts to strive for another fuel which can be used as an alternative or reduce the applications of fossil fuels. Considering the issues, the main objective of the present study is to find the feasibility by using blends of rice bran oil biodiesel and diesel which are used as pilot fuels by blending 10% and 20% biodiesel in fossil diesel and biogas, introduced as gaseous fuel by varying its mass flow rate in a dual-fuel engine mode. An experimentation study was carried out to find the performance and emission parameters of the engine relative to pure diesel. The results were very much similar to the majority of researchers who used biodiesel and gaseous fuels in a dual-fuel engine. Brake specific fuel consumption (BSFC) of the engine was noticed to have increased, while brake thermal efficiency was on the lower side in dual fuel mode in comparison with regular diesel. In relation with conventional diesel, it was noticed that combined effect of rice bran methyl esters and varying mass flow rate of biogas showed a decrement in NO x and smoke emissions, whereas HC and CO exhalations were on higher side when biogas and biodiesel were utilized collectively in dual-fuel engine. Hence, it was concluded that combination of blends of biodiesel and diesel and introduction of biogas in the engine can be a promising combination which can be used as a substitute fuel for addressing future energy needs.  相似文献   

11.
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.  相似文献   

12.
The environmental concern and availability of fuels are greatly affecting the trends of fuels for transportation vehicles. Biodiesel is one of the options as alternative transport fuel. This can be produced from straight vegetable oils (SVOs), oils extracted from various plant species and animal fats. Amongst many resources, availability and cost economy are the major factors affecting the large scale production of the biodiesels. The transesterification is one of the production processes for biodiesel, but incomplete esterification of all fatty acids in the starting material, lengthy purification methods such as water washing, relatively long reaction times, contamination and separation difficulties associated with co-production of glycerol and saponification of the starting material under certain reaction conditions are still being major challenges in the biodiesel production. Technological advancement and enhanced production methods are the demand of present time for large scale and sustainable production of biodiesel. In the present paper, comprehensive review on its production process, feed stock and its applications have been made. From many case studies it was concluded that engine performance with B20 biodiesel blends, and mineral diesel were found comparable.  相似文献   

13.
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. NOx 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.  相似文献   

14.
Global warming and tightening environmental legislation is putting pressure on divesting from fossil fuel in the energy sector, with the transport sector likely to see the biggest changes. Current alternative energy sources are electric vehicles and hydrogen. Conventional hydrogen production technologies are fossil fuel based, emitting significant amounts of CO2 into the atmosphere. This paper explores various ways to integrate solar thermal technologies into hydrogen production to generate carbon free hydrogen in South Africa. South Africa's abundant solar resource indicates that the country may become a significant player in the hydrogen market. However, the high capital cost associated with solar thermal energy put solar thermal hydrogen at a price disadvantage against conventional production technologies. Significant market penetration for solar thermal hydrogen is not expected within the next decade, but cost reduction due to improved manufacturing techniques and larger manufacturing volumes might close the gap in the long term.  相似文献   

15.
Biodiesel from palmoil—an analysis of its properties and potential   总被引:1,自引:0,他引:1  
If the agricultural products market is limited and much of agricultural land is not utilized as is the case in many countries in the world at present, then agriculture should be directed to the production of new alternative products. The land can be used to produce non-food products including biodiesels for the domestic energy market to diminish imports. Much research has been done on biodiesels over the last 20 yr after the oil crisis in 1973. At present, concern about environmental regulations has been the major reason to look for alternative fuel. A significant level in terms of physico-chemical properties of biodiesel has been obtained but there is a lack of full or partial replacement of fossil fuel that needs to be discussed.

This paper presents the experimental results carried out to evaluate the effect of anticorrosion additive in biodiesel (from palm oil) on diesel engines, performance, emissions and wear characteristics. This biodiesel is defined as the methyl ester of palm oil also known as palm oil diesel. The results of this investigation will be used to find compatible lubricant for biodiesel engine.  相似文献   


16.
Compression ignition engines are the dominant tools of the modern human life especially in the field of transportation. But, the increasing problematic issues such as decreasing reserves and environmental effects of diesel fuels which is the energy source of compression ignition engines forcing researchers to investigate alternative fuels for substitution or decreasing the dependency on fossil fuels. The mostly known alternative fuel is biodiesel fuel and many researchers are investigating the possible raw materials for biodiesel production. Also, hydrogen fuel is an alternative fuel which can be used in compression ignition engines for decreasing fuel consumption and hazardous exhaust emissions by enriching the fuel. In this study, influences of hydrogen enrichment to diesel and diesel tea seed oil biodiesel blends (B10 and B20) were investigated on an unmodified compression ignition engine experimentally. In consequence of the experiments, lower torque and higher brake specific fuel consumption data were measured when the engine was fuelled diesel biodiesel blends (B10 and B20) instead of diesel fuel. Also, diesel biodiesel blends increased CO2 and NOx emissions while decreasing the CO emissions. Hydrogen enrichment (5 l/m and 10 l/m) was improved the both torque and brake specific fuel consumption for all test fuels. Furthermore, hydrogen enrichment reduced CO and CO2 emissions due to absence of carbon atoms in the chemical structure for all test fuels. Increasing flow rate of hydrogen fuel from 5 l/m to 10 l/m further improved performance measures and emitted harmful gases except NOx. The most significant drawback of the hydrogen enrichment was the increased NOx emissions.  相似文献   

17.
Energy security is an important consideration for development of future transport fuels. Among the all gaseous fuels hydrogen or hydroxy (HHO) gas is considered to be one of the clean alternative fuels. Hydrogen is very flammable gas and storing and transporting of hydrogen gas safely is very difficult. Today, vehicles using pure hydrogen as fuel require stations with compressed or liquefied hydrogen stocks at high pressures from hydrogen production centres established with large investments.Different electrode design and different electrolytes have been tested to find the best electrode design and electrolyte for higher amount of HHO production using same electric energy. HHO is used as an additional fuel without storage tanks in the four strokes, 4-cylinder compression ignition engine and two-stroke, one-cylinder spark ignition engine without any structural changes. Later, previously developed commercially available dry cell HHO reactor used as a fuel additive to neat diesel fuel and biodiesel fuel mixtures. HHO gas is used to hydrogenate the compressed natural gas (CNG) and different amounts of HHO-CNG fuel mixtures are used in a pilot injection CI engine. Pure diesel fuel and diesel fuel + biodiesel mixtures with different volumetric flow rates are also used as pilot injection fuel in the test engine. The effects of HHO enrichment on engine performance and emissions in compression-ignition and spark-ignition engines have been examined in detail. It is found from the experiments that plate type reactor with NaOH produced more HHO gas with the same amount of catalyst and electric energy. All experimental results from Gasoline and Diesel Engines show that performance and exhaust emission values have improved with hydroxy gas addition to the fossil fuels except NOx exhaust emissions. The maximum average improvements in terms of performance and emissions of the gasoline and the diesel engine are both graphically and numerically expressed in results and discussions. The maximum average improvements obtained for brake power, brake torque and BSFC values of the gasoline engine were 27%, 32.4% and 16.3%, respectively. Furthermore, maximum improvements in performance data obtained with the use of HHO enriched biodiesel fuel mixture in diesel engine were 8.31% for brake power, 7.1% for brake torque and 10% for BSFC.  相似文献   

18.
Transportation has dominated global fuel consumption and greenhouse gas emissions have risen in an alarming rate. Gasoline and diesel consumption for road transport have a faster growing rate than other sector and the trend appeared to be rapidly moving upwards in the near future. This has caused much concern in many countries including Malaysia to improve the sustainable energy of this sector. The focus of this paper is to analyze the trends of energy pattern and emission of road transport in Malaysia. On top of that, the review of prospective policies such as fuel economy standards and fuel switching to natural gas as well as biodiesel are summarized in this study. The study found that there is an urgent need to adopt suitable energy policy to balance the energy demand and reduce emission in this sector. This study serves as a guideline for further investigation and research in order to implement and improve the transportation sector.  相似文献   

19.
Research on alternative fuel for the vehemently growing number of automotivesis intensified due to environmental reasons rather than turmoil in energy price and supply. From the policy and steps to emphasis the use of biofuel by governments all around the world, this can be comprehended that biofuel have placed itself as a number one substitute for fossil fuels. These phenomena made Southeast Asia a prominent exporter of biodiesel. But thrust in biodiesel production from oilseeds of palm and Jatropha curcas in Malaysia, Indonesia and Thailand is seriously threatening environmental harmony. This paper focuses on this critical issue of biodiesels environmental impacts, policy, standardization of this region as well as on the emission of biodiesel in automotive uses. To draw a bottom line on feasibilities of different feedstock of biodiesel, a critical analysis on oilseed yield rate, land use, engine emissions and oxidation stability is reviewed. Palm oil based biodiesel is clearly ahead in all these aspects of feasibility, except in the case of NOx where it lags from conventional petro diesel.  相似文献   

20.
As an alternative fuel for compression ignition engines, plant oils are in principle renewable and carbon-neutral. However, their use raises technical, economic and environmental issues. A comprehensive and up-to-date technical review of using both edible and non-edible plant oils (either pure or as blends with fossil diesel) in CI engines, based on comparisons with standard diesel fuel, has been carried out. The properties of several plant oils, and the results of engine tests using them, are reviewed based on the literature. Findings regarding engine performance, exhaust emissions and engine durability are collated. The causes of technical problems arising from the use of various oils are discussed, as are the modifications to oil and engine employed to alleviate these problems. The review shows that a number of plant oils can be used satisfactorily in CI engines, without transesterification, by preheating the oil and/or modifying the engine parameters and the maintenance schedule. As regards life-cycle energy and greenhouse gas emission analyses, these reveal considerable advantages of raw plant oils over fossil diesel and biodiesel. Typical results show that the life-cycle output-to-input energy ratio of raw plant oil is around 6 times higher than fossil diesel. Depending on either primary energy or fossil energy requirements, the life-cycle energy ratio of raw plant oil is in the range of 2–6 times higher than corresponding biodiesel. Moreover, raw plant oil has the highest potential of reducing life-cycle GHG emissions as compared to biodiesel and fossil diesel.  相似文献   

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