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排序方式: 共有332条查询结果,搜索用时 46 毫秒
1.
Rosana Fatima Galindo Luis Antonio Barbosa Cortez Telma Teixeira Franco 《化学工程与技术》2020,43(8):1530-1537
An alternative for reducing emissions from marine fuel is to blend bio-oil from lignocellulose non-edible feedstocks to diesel fossil fuels. Phase diagrams of the ternary systems were built to represent the transition from heterogeneous regions to homogeneous regions. Four homogeneous blends of bio-oil of eucalyptus-bioethanol-marine gasoil were experimentally characterized with respect to the most important fuel parameters for marine engines: water content, flash point, low heating value, viscosity, and acidity. Blends with closer properties to marine gasoil replacement, lower costs, and environmental impacts should be tested for large engines. 相似文献
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配制了典型的模型油模拟提质产物中的中质成分(沸点为80~200℃),在1台单缸4冲程汽油机上对模型油、模型油-汽油混合燃料及汽油进行试验研究.结果表明:调整化油器结构适当增加供油量,在不改变发动机其他特性的条件下,燃用模型油的动力略微下降,下降幅度在5%以内,能耗率平均下降了8.47%;HC和CO排放远远低于汽油,平均下降了42.97%和66.7%,但NOX和CO2排放明显上升,相对汽油平均分别上升了29.47%和20.17%.对汽油机不作任何调整,燃用模型油体积分数10%(B10)和20%(B20)的混合燃料的动力特性及排放特性一般介于汽油与模型油之间. 相似文献
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为了探究稻壳类生物质油替代石油沥青的微观作用机理,以稻壳类生物质油和6种石油沥青为原材料,制备稻壳类生物沥青。采用针入度、软化点和延度指标评价稻壳类生物沥青的物理性能,通过傅里叶红外光谱实验(FTIR)和高温凝胶色谱实验(GPC)探究稻壳类生物沥青的微观作用机理。研究表明,稻壳类生物质油会使石油沥青的针入度和延度增大,同时使软化点略有降低;稻壳类生物质油与6种石油沥青的官能团相似,且生物沥青制备时未产生新的官能团;随着稻壳类生物质油的掺加,6种生物沥青中的小分子和中分子含量增加,大分子的含量变化不大,稻壳类生物质油小分子和中分子含量较多,生物沥青的数均分子量Mn和重均分子量Mw均降低。稻壳类生物质油的加入,使石油沥青的低温性能提高,流动性增大,高温性能稍有降低但并不会降低石油沥青的高温等级,稻壳类生物质油可以作为石油沥青的替代材料使用。 相似文献
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Tevfik Aysu Halil Durak 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(5):661-669
Slow pyrolysis of giant mullein (Verbascum thapsus L.) stalks have been carried out in a fixed-bed tubular reactor with (Al2O3, ZnO) and without catalyst at four different temperatures between 400 to 550°C with a constant heating rate of 50°C/min and with a constant sweeping gas (N2) flow rate of 100 cm3/min. The amounts of bio-char, bio-oil, and gas produced were calculated and the compositions of the obtained bio-oils were determined by gas chromatography-mass spectrometry. The effects of pyrolysis parameters, such as temperature and catalyst, on the product yields were investigated. The results show that both temperature and catalyst have significant effects on the conversion of Verbascum thapsus L. into solid, liquid, and gaseous products. The highest liquid yield of 40.43% by weight including the aqeous phase was obtained with 10% zinc oxide catalyst at 500°C temperature. Sixty-seven different products were identified by gas chromatography-mass spectrometry in the bio-oils obtained at 500°C temperature. 相似文献
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P. Madhu I. Neethi Manickam H. Kanagasabapathy 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(15):2161-2169
New and renewable fuels are the major alternatives to conventional fossil fuels. Biomass in the form of agricultural residues is becoming popular among new renewable energy sources, especially given its wide potential and abundant usage. This study deals with the characterization of the pyrolysis oil obtained from palmyra palm fruit bunch (Borassus flabellifer) produced by flash pyrolysis in the maximum yield. The pyrolysis oil was analyzed to determine its elemental composition and heating value. The chemical composition of the pyrolysis oil and fractions was investigated using various chromatographic techniques such as Fourier transform infra-red (FTIR) spectroscopy, gas chromatography–mass spectroscopy (GC-MS), and 1H NMR spectroscopy. The bio-oil product was presented as an environmentally friendly green biofuel candidate. The analytical results showed that the pyrolysis bio-oils were very complex mixtures of organic compounds and contained a lot of nitrogenated and oxygenated compounds such as, phenols, aliphatic hydrocarbons, pyridines, amines, ketones, and so on. 相似文献
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Beatriz Valle Aingeru Remiro Naiara García-Gómez Ana G Gayubo Javier Bilbao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2019,94(3):670-689
Recent advances in lignocellulosic biomass valorization for producing fuels and commodities (olefins and BTX aromatics) are gathered in this paper, with a focus on the conversion of bio-oil (produced by fast pyrolysis of biomass). The main valorization routes are: (i) conditioning of bio-oil (by esterification, aldol condensation, ketonization, in situ cracking, and mild hydrodeoxygenation) for its use as a fuel or stable raw material for further catalytic processing; (ii) production of fuels by deep hydrodeoxygenation; (iii) ex situ catalytic cracking (in line) of the volatiles produced in biomass pyrolysis, aimed at the selective production of olefins and aromatics; (iv) cracking of raw bio-oil in units designed with specific objectives concerning selectivity; and (v) processing in fluidized bed catalytic cracking (FCC) units. This review deals with the technological evolution of these routes, in terms of catalysts, reaction conditions, reactors, and product yields. A study has been carried out on the current state-of-knowledge of the technological capacity, advantages and disadvantages of the different routes, as well as on the prospects for the implementation of each route within the scope of the Sustainable Refinery. © 2018 Society of Chemical Industry 相似文献
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Fast pyrolysis of the crushed Delonix regia seed was carried out in a semi-batch reactor at a temperature ranging from 400 to 650°C with an objective to produce bio-oil. The effect of temperature to obtain an optimum condition for maximum bio-oil yield and the composition of pyrolysis product were investigated. The maximum bio-oil yield was found to be 48?wt% at pyrolysis temperature of 600°C. The chemical composition of bio-oil obtained at optimum condition was analysed using Fourier-transformed infrared spectroscopy and Gas chromatography–mass spectrometry. The chemical analysis of the biofuel showed the presence of hydrocarbons in major, aldehydes, ketones, amides, nitriles, etc. The composition and fuel characteristics of the pyrolysis oil obtained in this work show that it may potentially be used as a renewable fuel and chemical feedstock. 相似文献
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《International Journal of Hydrogen Energy》2014,39(35):19955-19969
Chemical looping hydrogen (CLH) process with renewable energy sources as fuel shows the potential of producing pure hydrogen with inherent capture of CO2 in a low-cost and sustainable way. The heavy fraction (HF) of bio-oil, derived from the fast pyrolysis of biomass and characterized as an energy carrier with difficulty in upgrading itself to bio-fuel or chemicals, was used in this study to generate H2. Four low-cost iron-based oxygen carriers including an ilmenite and three iron ores were initially evaluated with respect to their reducibility and the ability to minimize carbon or iron carbide (Fe3C) formation in a thermogravimetric analyzer (TGA). The reactivity and cyclic performance of the selected best candidate was then assessed in a laboratory scale fixed-bed reactor with HF bio-oil as fuel. The screening test in TGA showed that ilmenite was superior over the three iron ores in terms of promoting CO conversion and minimizing carbon or Fe3C formation. Ilmenite could maintain its increasing reducibility with the increase of surrounding CO concentration, in contrast with the iron ores that were deactivated seriously by the formed carbon or Fe3C. Subsequent CLH test with ilmenite and HF bio-oil showed that the reducibility and H2 production capacity of ilmenite were strongly dependent on the operating temperature. The steam oxidation step at 950 °C yielded H2 concentration and hydrogen yield exceeding all of those observed at the other investigated temperatures because of the deepest reduction degree of ilmenite at 950 °C. The decrease in the reducibility and H2 production capacity of ilmenite in the cyclic test could be ascribed to the poorer physical structure of ilmenite with cycles. 相似文献