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1.
Iran’s diversity of terrain and climate enables cultivation of a variety of energy crops suitable for liquid biofuels production. In Iran, the easily and readily available biofuel feedstock today for production of bioethanol is molasses from sugar cane and sugar beet. There is also about 17.86 million tons of crops waste from which nearly 5 billion liters of bioethanol could be produced annually. This amount of bioethanol is sufficient to carry out E10 for spark ignition engine vehicles in Iran by 2026. There is also enormous potential for cultivation of energy plants such as cellulosic materials and algae. Iran has 7%of its area covered with forest products which are suitable sources for liquid biofuels such bioethanol and biodiesel. Iran also has a long tradition of fishing in Caspian Sea and Persian Gulf with about 3200 km coastline and on inland rivers. The produced fish oil and other plant oils such as palm tree, jatropha, castor plant and algae are suitable biodiesel feedstock. Out of 1.5 million tons of edible cooking oil consumed in Iran annually, about 20% of it can be considered as waste, which is suitable biodiesel feedstock.This quantity along with the other possible potential feedstock are favorable sources to carry out B10 step by step until 2026.  相似文献   

2.
Microalgae for biodiesel production and other applications: A review   总被引:18,自引:0,他引:18  
Sustainable production of renewable energy is being hotly debated globally since it is increasingly understood that first generation biofuels, primarily produced from food crops and mostly oil seeds are limited in their ability to achieve targets for biofuel production, climate change mitigation and economic growth. These concerns have increased the interest in developing second generation biofuels produced from non-food feedstocks such as microalgae, which potentially offer greatest opportunities in the longer term. This paper reviews the current status of microalgae use for biodiesel production, including their cultivation, harvesting, and processing. The microalgae species most used for biodiesel production are presented and their main advantages described in comparison with other available biodiesel feedstocks. The various aspects associated with the design of microalgae production units are described, giving an overview of the current state of development of algae cultivation systems (photo-bioreactors and open ponds). Other potential applications and products from microalgae are also presented such as for biological sequestration of CO2, wastewater treatment, in human health, as food additive, and for aquaculture.  相似文献   

3.
Global warming, depletion of fossil fuel and increasing demand for energy have led to the substantial interest in developing alternate energy sources, especially biodiesel. First generation biofuels produced from food crops and oil seeds are limited to achieve targets for biodiesel production. Second generation biofuel produced from non-food feed stock such as microalgae provides various potential advantages for biofuel production when compared with first generation biofuels. This paper investigates the possible use of microalgae for biofuel production on the selected potential sites in the country. Algal biomass and oil yield for the selected sites are predicted using the analytical method.  相似文献   

4.
Algal biomass provides viable third generation feedstock for liquid transportation fuel that does not compete with food crops for cropland. However, fossil energy inputs and intensive water usage diminishes the positive aspects of algal energy production. An integrated renewable energy park (IREP) approach is proposed for aligning renewable energy industries in resource-specific regions in United States for synergistic electricity and liquid biofuel production from algal biomass with net zero carbon emissions. The benefits, challenges and policy needs of this approach are discussed.  相似文献   

5.
海藻生物燃料产业化开发的进展   总被引:3,自引:0,他引:3  
刘永平 《中外能源》2009,14(9):31-38
海藻种类多样、光合作用效率高、生长周期短、生物产量高、自身合成油脂能力强,同时还能大量吸收CO2,是制备生物柴油最佳的生物质原料之一。国内外对海藻生物燃料技术的研发均取得一定成果。海藻生物柴油的生产过程主要包括海藻大规模培养、海藻油萃取、酯交换反应、生物柴油后处理4个步骤,而最重要的是海藻的大规模培养。光生物反应器已成为高效、快速、大量培养藻类的关键没备,其一般分为开放式和封闭式两种。AlgaeLink NV公司的海藻光生物反应器是目前世界上唯一已商业化的小型装置。我国企业采用自主研发的反应器装置,通过对环境条件因素进行控制,在技术上已达到海藻含油率40%,日产量1~1.4kg/m^3。当海藻含油率达到60%,日产量平均达到3kg/m^3以上时,海藻生物柴油的生产成本将接近石油柴油的批发价,海藻生物柴油产业将成为一个新兴的替代能源产业。  相似文献   

6.
Biofuels have had bad press in recent years. There are primarily two distinct issues. The biofuel crops with the best yields (such as sugarcane or oil palm) grow in tropical countries where habitat destruction has occurred in association with the biofuel system. First generation indigenous energy crops commonly used for transport fuel in Europe (such as rapeseed and wheat) have low yields and/or the energy balance of the associated biofuel system is poor. This paper shows that grass is a crop with significant yields and grass biomethane (a gaseous renewable transport biofuel) has a very good energy balance and does not involve habitat destruction, land use change, new farming practices or annual tilling. The gross and net energy production per hectare are almost identical to palm oil biodiesel; the net energy of the grass system is at least 50% better than the next best indigenous European biofuel system investigated. Ten percent of Irish grasslands could fuel over 55% of the Irish private car fleet.  相似文献   

7.
In this study, the policy, market conditions and food security of biomass energy sources are assessed for supplying the future needs of Vojvodina. The Autonomous Province of Vojvodina is an autonomous province in Serbia, containing about 27% of its total population according to the 2002 Census. It is located in the northern part of the country, in the Pannonia plain, in southeastern Europe.Vojvodina is an energy-deficient province. Vojvodina also has a large potential for renewable energy, especially energy from biomass (biodiesel and bio-ethanol). The lack of knowledge about renewable energy technologies by most policy-makers, potential consumers, and energy firm managers has played against renewable energy developments. The environmental impacts of programs that encourage biofuel production, farmland land requirements and the impacts on food production are also discussed, considering the life cycle analysis (LCA) as a tool.It is concluded that the rise in the use of biofuels is inevitable and that international cooperation, regulations and certification mechanisms must be established regarding the use of land, the mitigation of environmental and social impacts caused by biofuel production. It is also mandatory to establish appropriate working conditions and decent remuneration for workers of the biofuels production chain.  相似文献   

8.
Microalgae are photosynthetic microorganisms that can produce lipids, proteins and carbohydrates in large amounts over short periods of time. These products can be processed into both biofuels and useful chemicals. Two algae samples (Cladophora fracta and Chlorella protothecoid) were studied for biofuel production. Microalgae appear to be the only source of renewable biodiesel that is capable of meeting the global demand for transport fuels. Microalgae can be converted to biodiesel, bioethanol, bio-oil, biohydrogen and biomethane via thermochemical and biochemical methods. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae can be grown almost anywhere, even on sewage or salt water, and does not require fertile land or food crops, and processing requires less energy than the algae provides. Microalgae have much faster growth-rates than terrestrial crops. the per unit area yield of oil from algae is estimated to be from 20,000 to 80,000 liters per acre, per year; this is 7–31 times greater than the next best crop, palm oil. Algal oil can be used to make biodiesel for cars, trucks, and airplanes. The lipid and fatty acid contents of microalgae vary in accordance with culture conditions. The effect of temperature on the yield of hydrogen from two algae (C. fracta and C. protothecoid) by pyrolysis and steam gasification were investigated in this study. In each run, the main components of the gas phase were CO2, CO, H2, and CH4.The yields of hydrogen by pyrolysis and steam gasification processes of the samples increased with temperature. The yields of gaseous products from the samples of C. fracta and C. protothecoides increased from 8.2% to 39.2% and 9.5% to 40.6% by volume, respectively, while the final pyrolysis temperature was increased from 575 to 925 K. The percent of hydrogen in gaseous products from the samples of C. fracta and C. protothecoides increased from 25.8% to 44.4% and 27.6% to 48.7% by volume, respectively, while the final pyrolysis temperature was increased from 650 to 925 K. The percent of hydrogen in gaseous products from the samples of C. fracta and C. protothecoides increased from 26.3% to 54.7% and 28.1% to 57.6% by volume, respectively, while the final gasification temperature was increased from 825 to 1225 K. In general, algae gaseous products are higher quality than gaseous products from mosses.  相似文献   

9.
Hawaii’s agricultural sector has an immense supply of natural resources that can be further developed and utilized to produce biofuel. Transformation of the renewable and abundant biomass resources into a cost competitive, high performance biofuel could reduce Hawaii’s dependence on fossil fuel importation and enhance energy security. The objectives of the study are to evaluate the economic feasibility of selected bioenergy crops for Hawaii and compare their cost competitiveness. The selected feedstock consists of both ethanol and biodiesel producing crops. Ethanol feedstock includes sugar feedstock (sugarcane) and lignocellulosic feedstock (banagrass, Eucalyptus, and Leucaena). Biodiesel feedstock consists of Jatropha and oil palm.The economic analysis is divided into two parts. First, a financial analysis was used to select feasible feedstock for biofuel production. For each feedstock, net return, feedstock cost per Btu, feedstock cost per gallon of ethanol/biodiesel, breakeven price of feedstock and breakeven price of ethanol/biodiesel were calculated. Leucaena shows the lowest feedstock cost per Btu while banagrass has the highest positive net returns in terms of both feedstock price and energy price.The second approach assumes an objective of maximizing net returns. Given this assumption, biofuel producers will produce only banagrass. As an example, the production of bioenergy on the island of Hawaii is illustrated where 74,793 acres of non-prime land having a “warm and moist” soil temperature and moisture regime are available. Using average yields (static optimization), banagrass production on this acreage can yield 8.24 trillion Btus of energy (ethanol). This satisfies the State’s 10% self-sufficiency energy goal of 3.9 trillion Btus by 2010. Incorporating risk through variability in crop yields and biofuel prices separately shows banagrass as having the highest probability for receiving a positive net return. Banagrass is the leading candidate crop for biofuel production in Hawaii and the State of Hawaii ethanol goal can be achieved by allocating non-prime lands for banagrass production without compromising prime lands currently allocated for agricultural food production in Hawaii. Physical, environmental and socio-economic impacts should be accounted for in evaluating future biofuel projects.  相似文献   

10.
Biodiesel is a renewable and sustainable biofuel. There are various production processes to produce biodiesel from different kinds of raw materials. In this study, the environmental impacts of biodiesel production from non-edible Jatropha oil and waste cooking oil (WCO) were investigated and compared using systematic life cycle assessment. The results show that crops growing and cultivation of non-edible Jatropha curcas lead to higher environmental impacts compared to WCO process. However, biodiesel production process from Jatropha oil has better performance because the WCO process needs to consume variety of chemicals and requires a large amount of energy for the pretreatment of raw WCO and further chemical conversion to biodiesel. Results also indicate that the collection mechanism of WCO has significant contributions towards environmental impacts. In general, biodiesel production from Jatropha oil shows higher impacts for damage categories of climate change, human health and ecosystem quality whereas biodiesel production from WCO has more severe environmental impacts for resource category. The total environmental impact is 74% less in case of using WCO as raw material compared to non-edible Jatropha oil.  相似文献   

11.
Iran, as a developing country, will be confronted with a significant increase in electricity demand in future years. Being a petroleum producing country has resulted in extreme subsidies for energy production from fossilized resources such as oil and gas. This issue is one of the most important factors regarding underdevelopment of renewable energies in Iran. Expansive use of fossil resources in providing the necessary energy has resulted in Iran being among the 20 countries that have a share in the 75% spread of greenhouse gases. This issue has resulted in greater attention on behalf of the energy sectors policy makers regarding renewable energies, especially wind. Awareness regarding the current condition of each system is the first step for optimum policy making. On this basis, analyzing Iran's wind conditions and assessing its technological capabilities is considered a pre-requisite for the wind sectors policy making. This paper aims at studying Iran's wind energy status in the form of available capacities, power production, wind power plant characteristics, principal agents and existing protective laws. Also, the main focus of this paper is on evaluating Iran's potential and effective technological capabilities for producing the main parts of wind turbines in different sizes. In order to fulfill this task, sector-level technological capabilities are defined. Then by analyzing active organizations in this field, Iran's capability level will be determined and by comparing it with the ideal conditions, Iran's technological gaps will be identified. The reasons for the creation of such shortcomings will also be introduced from different aspects in the form of the Atlas model. Finally, Iran's potential capabilities in resolving technological shortcomings will be identified.  相似文献   

12.
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   

13.
E.E. Powell  G.A. Hill   《Energy》2010,35(12):4582-4586
Algae are efficient biocatalysts for both capture and conversion of carbon dioxide in the environment. In earlier work, we have optimized the ability of Chlorella vulgaris to rapidly capture CO2 from man-made emission sources by varying environmental growth conditions and bioreactor design. Here we demonstrate that a coupled biodiesel-bioethanol facility, using yeast to produce ethanol and photosynthetic algae to produce biodiesel, can result in an integrated, economical, large-scale process for biofuel production. Each bioreactor acts as an electrode for a coupled complete microbial fuel cell system; the integrated cultures produce electricity that is consumed as an energy source within the process. Finally, both the produced yeast and spent algae biomass can be used as added value byproducts in the feed or food industries. Using cost and revenue estimations, an IRR of up to 25% is calculated using a 5 year project lifespan.  相似文献   

14.
Algae species like Schizochytrium sp. are resilient photosynthetic factories that produce large quantities of fatty acids that can be converted to biodiesel. These lipids must be extracted from the raw biomass before they can be used as biofuel feedstocks or other bioproducts such as hydrogen. In this paper, hydrogen production by steam reforming of schizochytrium algae oil are studied. The effects of continuous microwave and intermittent microwave, freezing and thawing times of different mass fractions, time of alkali heat and other factors on the ratio of cell disruption and ultrasonic-assisted ethanol extraction are considered. The results show that the highest lipid yield can reach by ultrasonic-assisted ethanol extraction from the schizochytrium algae which are pretreated by alkali heat method. The hydrogen production from steam reforming of the lipids, which are extracted by ethanol with ultrasonic-assisted from algae after alkali thermal pretreated is proposed.  相似文献   

15.
Production of bioethanol is winning support from masses because it is a workable choice to solve the problems associated with the fluctuating prices of crude petroleum oil, climatic change, and reducing non‐renewable fuel reserves. First‐generation biofuels are produced directly from food crops. The biofuel (bioethanol, biodiesel) is ultimately derived from the starch, sugar, animal fats, and vegetable oil that these crops provide. It is important to note that the structure of the biofuel itself does not change between generations, but rather the source from which the fuel is derived changes. Corn, wheat, and sugar cane are the most commonly used first‐generation bioethanol feed stocks. Lignocellulosic materials are used as a feed stock for the production of second‐generation bioethanol. The major production steps are (1) delignification, (2) depolymerisation, and (3) fermentation. Agricultural residues are waste materials produced through the processing of agricultural crops. The main reason to use of these agricultural residues to produce bioethanol is to convert waste to value added products. The main challenges are the low yield of the cellulosic hydrolysis process due to the presence of lignin and hemicellulose with cellulose. Pretreatments of lignocellulosic materials to remove lignin and hemicellulose are the techniques used to enhance the hydrolysis. Present review article comprehensively discusses the different pretreatment methods of delignification for ethanol production. Published literature on pretreatments from 1982 to 2018 has been studied. Perspectives, gaps in studies, and recommendations are given to fully describe implementation of eight prominent pretreatments (milling, pyrolysis, organic solvents, steam explosion, hot water treatments, ozonolysis, enzymatic delignification, and genetic modification) for future research. The energy and environmental features of lignocellulosic materials are elaborated to show a sustainable aspect of second‐generation biofuel. It was felt necessary to discuss the concept of bio refinery to make biofuel production financially more attractive as well because the future prospects of second‐generation biofuel are promising.  相似文献   

16.
The massive need for sustainable energy has led to an increased interest in new energy resources, such as production of algae, for use as biofuel. There are advantages to using algae, for example, land use is much less than in terrestrial biofuel production, and several algae species can double their mass in 1 day under optimized conditions. Most algae are phototrophs and some are nitrogen-fixing. Algae production therefore requires only small amounts of amendments such as carbon sources and nutrients. In the present paper an experiment was performed using water sampled from Lake Mälaren in Sweden. The lake water is considered nutrient rich, has relatively neutral pH and is rich in organic compounds and suspended solids. The idea behind this research was to enhance indigenous algae production rather than inoculate new species into the system. A simple experimental setup was designed where algae biomass growth was measured regularly over a 13 day period. FT-IR absorption spectra were evaluated in order to determine protein, lipid, carbohydrate and silicate contents of the algae. The algae community structure was characterized throughout the production cycle. Furthermore, the potential for energy supply for the transportation sector in the Mälardalen region from algae cultivated as tested in the experiment was evaluated.  相似文献   

17.
The purpose of this work is to investigate fuel characteristics of biodiesel and its production in European Union. Biodiesel fuel can be made from new or used vegetable oils and animal fats, which are non-toxic, biodegradable, renewable resources. The vegetable oil fuels were not acceptable because they were more expensive than petroleum fuels. Biodiesel has become more attractive recently because of its environmental benefits. With recent increases in petroleum prices and uncertainties concerning petroleum availability, there is renewed interest in vegetable oil fuels for diesel engines. In Europe the most important biofuel is biodiesel. In the European Union biodiesel is the by far biggest biofuel and represents 82% of the biofuel production. Biodiesel production for 2003 in EU-25 was 1,504,000 tons.  相似文献   

18.
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   

19.
The challenges in reducing the world's dependence on crude oil and the greenhouse gas accumulation in the atmosphere, while simultaneously improving engine performance through better fuel efficiency and reduced exhaust emissions, have led to the emergence of new fuels, with formulations blending petrodiesel, biodiesel, bioethanol and water in various proportions. In parallel, the sustainability of the new biofuel industries also requires to maintain a high level of biodiversity while playing on techno-diversity, using a variety of resources that do not compete with edible crops (nor by using arable land for energy crops or food crops for energy production) and flexible conversion technologies satisfying the eco-design, eco-energy and eco-materials criteria. In addition, it would be relevant to consider blending ethyl biodiesel, instead of methyl biodiesel, with petrodiesel, particularly if the fuel formulation is completed with bioethanol (or even water). The supercritical ethanolysis of lipid resources to produce ethyl biodiesel is a simple but efficient route that should have the potential to satisfy the sustainability criteria if analyzed holistically. Therefore, this review focuses specifically on the production of ethyl biodiesel via triglyceride supercritical ethanolysis within a global analysis “feedstocks-conversion-engine”. The scientific and technical bottlenecks requiring further development are highlighted by emphasizing (i) the kinetic and thermodynamic aspects (experiments and modeling) required for the process simulation, the results of which aim at securing the life cycle assessment, first at the process level and then at the fuel level; (ii) the proposals to improve the supercritical process performance in terms of eco-material and eco-energy; (iii) the impacts of ethyl vs. methyl biodiesel fuels and of biodiesel–ethanol–petrodiesel blends (with or without water) on the diesel engine emissions and performance; (iv) the technological flexibility of the supercritical process allowing its conversion toward production of other key products. Finally, built on the state-of-the art review, a new R&D direction combining supercritical ethanolysis of lipids with the addition of CO2, glycerol recovery, and cogeneration, according to the biorefinery concept, is proposed and discussed.  相似文献   

20.
The quest for renewable energy has intensified since the escalating price of crude petroleum in the recent years. Renewable energy such as biodiesel has the potential to replace petroleum-derived transportation fuel in the future. Biodiesel is defined as the mono-alkyl esters of long-chain fatty acids derived from vegetable oils such palm oil, rapeseed and soybean. Currently, more than 80% of the world biodiesel productions are from rapeseed oil. However, the cost of palm oil which is at least US$ 200 per tonne cheaper than rapeseed oil indicates that palm oil could be a more suitable and attractive candidate as the source of biodiesel compared to other vegetable oils. Although palm oil is known to be a multi-purpose vegetable oil with products ranging from food to biodiesel, there are a lot of issues surrounding palm oil production. Nevertheless, some of these issues reported in the literature were found to be misleading and are thus confusing the public perception on palm oil. Thus, the aim of this paper is to highlight and clarify the negative issues reported in the literature surrounding palm oil production. Apart from that, various policies or/and strategies that will lead to a more sustainable production and development of palm oil industries will also be proposed. Hence, palm oil will be able to become the leading vegetable oil in terms of food and non-food production, especially as the main source of renewable energy, biodiesel.  相似文献   

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