燃料乙醇产业发展综述

燃料乙醇是一种性能好、有发展前途的清洁燃料。本文分析了我国开发燃料乙醇的必要性,我国燃料乙醇的发展现状,燃料乙醇生产技术概况,燃料乙醇的发展趋势。     

燃料乙醇的生产进展和应用探讨

介绍了乙醇的生产技术研究现状、燃料乙醇的生产新工艺和发展现状：对比分析了国内外燃料乙醇标准：讨论了我国应用燃料乙醇生产乙醇汽油的补贴计算方法及开发乙醇柴油的前景，提出以体积为计价单位、扩大原料来源，搞好综合利用、降低生产成本的建议。     

燃料乙醇领域的专利状况分析

燃料乙醇作为一种新的可再生能源,能够降低对不可再生能源——石油的依赖。在我国,多个部门均发布了燃料乙醇相关的产业政策,为燃料乙醇领域的技术发展铺平了道路。本文梳理了燃料乙醇领域的各国国家政策、技术发展现状及专利状况分析,详细分析了燃料乙醇领域中生产原料的专利状况。为燃料乙醇领域的技术企业提供专利数据支持,并对燃料乙醇领域的技术发展提供建议和展望。     

乙醇柴油燃料的研究进展

根据乙醇与柴油的理化性质论述了乙醇作为柴油代用燃料的特点,介绍了乙醇在柴油机中的燃烧方式和节能、环保机理,综述了国内外乙醇柴油燃料的研究进展,最后总结了应用乙醇柴油燃料的意义。     

纤维素燃料乙醇研究进展

纤维素燃料乙醇是当今世界可再生生物质能源研究的热点。文章综述了纤维素燃料乙醇生产技术以及纤维素燃料乙醇产业的发展概况。分析了纤维素燃料乙醇产业化过程中出现的关键技术问题,并提出了相应建议。     

燃料乙醇发展现状和前景展望

介绍了国内外燃料乙醇的发展现状以及我国对于发展燃料乙醇的相关政策,从成本、原料、粮食安全、市场及经济性方面进行了分析,建议应借助人大立法,保证燃料乙醇推广的顺利进行;政府应制定补贴、免征税收等政策并及时落实;积极推进燃料乙醇新技术的开发工作;扩大燃料乙醇应用范围,推进燃料乙醇的应用进程;开展乙醇化工的研究。     

燃料乙醇的研究与展望

通过介绍发酵法,乙醇脱水制造燃料乙醇的方法,正确定位燃科乙醇足油品的优良品质改良剂,燃料乙醇不足"油",是一种可再生能源,燃料乙醇的辛烷值高抗爆性能好,且能减少多大气的污染,可作为新的燃料替代品.     

云南省燃料乙醇产业发展现状与对策

以云南省燃料乙醇产业发展形势、资源潜力、区位优势为背景,阐述了云南省燃料乙醇产业发展的现状。提出从政策保障角度,云南省燃料乙醇产业发展可从积极争取国家燃料乙醇试点省份,成立专门的燃料乙醇协调部门、建立专项补贴资金体系,形成一定规模的燃料乙醇试点、优先拉通产业链、为燃料乙醇推广形成示范效应等对策方面加以完善;从原料保障角度,可从保障甘蔗原料供应、扩大薯类原料种植面积、积极促进土地流转、建立集约化种植管理模式、开发境外种植基地等方面加以提升。最后提出云南省燃料乙醇产业发展措施,整合省内中小型乙醇生产企业以形成规模效应,综合发展以形成产业链并降低燃料乙醇生产成本。     

发酵法制乙醇的研究现状及展望

当今,石油、煤等传统化石能源日渐匮乏,并且由之带来了环境污染问题,使得全球都在寻找清洁可再生能源替代传统能源。燃料乙醇具有清洁、可再生的特点,并且制备燃料乙醇的原料易得,所以,燃料乙醇的研究已逐渐成为热点。主要介绍了全球燃料乙醇发展现状,综述了用发酵法制备燃料乙醇的研究现状及适宜的工艺条件,总结了制备燃料乙醇存在的问题及解决方法,并且对未来燃料乙醇的发展进行了展望。     

燃料乙醇技术研究现状和发展趋势分析

介绍了近年来国内外燃料乙醇研究开发历程和最新进展,对化学合成燃料乙醇技术、生物发酵制乙醇技术进行了分析对比。对纤维素制燃料乙醇技术存在的困难和问题进行了分析。对影响燃料乙醇产业发展的因素进行了探讨。提出了我国燃料乙醇技术研发和产业发展的相关建议,认为我国应加强非粮燃料乙醇配套技术研发,探索微藻乙醇技术开发,促进非粮燃料乙醇产业发展。     

Residential Solid Oxide Fuel Cell Generator Fuelled by Ethanol: Cell,Stack and System Modelling with a Preliminary Experiment

The flexibility and feasibility of a 5 kW SOFC generator designed for natural gas (NG) and fuelled by a non‐conventional liquid fuel such as ethanol is analysed. A complete generator model is implemented to predict and determine the main criticalities when ethanol fuel is adoperated. The main balance‐of‐plant (BoP) units considered are the reformer, the recirculation system based on an ejector, the tubular cells bundles constituting the stack unit, the after‐burner zone and the air blower. The electrical and global efficiencies achieved at nominal operating conditions show how ethanol maintains generator performance good, while only slightly reducing the system AC efficiency from 48% (achieved by NG) to 45%. The effectiveness and flexibility of the recirculation system when changing the fuel is also verified since a safe steam‐to‐carbon ratio (STCR) is established after the fuel is switched from NG ethanol. The stack thermal management is analysed in detail and related to the system performances, showing how a high endothermic fuel reforming reaction is required to maintain the overall system efficiency. A preliminary experiment with ethanol feeding the Siemens generator is finally presented. The system response to the new fuel is monitored by several measured parameters and the system regulation is explained.     

Influence of ethanol blends on the combustion performance and exhaust emission characteristics of a four-cylinder diesel engine at various engine loads and injection timings

The aim of this work is to investigate the effect of ethanol blending to diesel fuel on the combustion and exhaust emission characteristics of a four-cylinder diesel engine with a common-rail injection system. The overall spray characteristics, such as the spray tip penetration and the spray cone angle, were studied with respect to the ethanol blending ratio. A spray visualization system and a four-cylinder diesel engine equipped with a combustion and emission analyzer were utilized so as to analyze the spray and exhaust emission characteristics of the ethanol blending diesel fuel. Ethanol blended diesel fuel has a shorter spray tip penetration when compared to pure diesel fuel. In addition, the spray cone angle of ethanol blended fuels is larger. It is believed that the lower fuel density of ethanol blended fuels affects the spray characteristics. When the ethanol blended fuels are injected around top dead center (TDC), they exhibit unstable ignition characteristics because the higher ethanol blending ratio causes a long ignition delay. An advance in the injection timing also induces an increase in the combustion pressure due to the sufficient premixed duration. In a four-cylinder diesel engine, an increase in the ethanol blending ratio leads to a decrease in NO_x emissions due to the high heat of evaporation of ethanol fuel, however, CO and HC emissions increase. In addition, the CO and HC emissions exhibit a decreasing trend according to an increase in the engine load and an advance in the injection timing.     

Ethanol crossover and direct ethanol PEM fuel cell performance modeling and experimental validation

In the present work, a one-dimension, steady-state and single phase model is developed with the purpose of describing the mass transport within a PtRu/Nafion^®-115/Pt membrane-electrode assembly and the performance of a direct ethanol proton exchange membrane fuel cell (DE-PEMFC). The effect of the most important cell operating parameters on the ethanol crossover rate and the fuel cell performance is investigated. According to the results, in the case of low current density values and high concentrations of ethanol aqueous solutions, ethanol crossover could pose serious problems to the DEFC operation. Moreover, it was pointed out that the ethanol crossover rate dependence on the ethanol feed concentration is an almost linear function presenting a maximum at about . A further increase of the ethanol feed concentration leads to a steep decrease of ethanol crossover rate. This behavior could be attributed to the membrane swelling which is responsible for the membrane volume fraction decrement. It was also found that by the aid of the same model the performance of a direct ethanol PEM fuel cell over three different anode catalysts can be predicted. A relatively good agreement between theory and experimental results related to both ethanol crossover rates and direct ethanol fuel cell performance was found.     

Combustion of bio-oil ethanol blends at elevated pressure

This paper reports an investigation on the combustion performance of bio-oil/ethanol blends. Experiments were conducted in a constant volume vessel operating at a pressure of 25 bar and temperature 1100 K. Bio-oil produced via the fast pyrolysis of a spruce feedstock was blended to ethanol to form three stable blends containing 10%, 20% and 40% bio-oil by weight. In addition, ethanol and standard automotive grade diesel were tested as reference fuels. Measured vessel pressure was used in a single-zone heat release analysis, while two-colour optical pyrometry was used to investigate particle loading and temperature. Results show that for similar injections of fuel energy, use of up to 20% bio-oil in ethanol has limited impact on the performance of ethanol while 40% bio-oil in ethanol produced instability in the pressure trace near the end of the combustion process. Burning rates are similar for blends and ethanol. Addition of bio-oil to ethanol was found to increase combustion generated particle load, and this increased with bio-oil concentration, but remained much lower than particle concentration in diesel. Addition of bio-oil also resulted in formation of char particles that appear as luminous clusters outside the boundary of the spray. This suggests these particles will cool rather than oxidize. The presence of unburnt char particles in large numbers may have consequences for bio-oil as an alternative diesel fuel.     

Hydrous ethanol vs. gasoline-ethanol blend: Engine performance and emissions

This work compares the performance and emissions from a production 1.0-l, eight-valve, and four-stroke engine fuelled by hydrous ethanol (6.8% water content in ethanol) or 78% gasoline-22% ethanol blend. The engine was tested in a dynamometer bench in compliance with NBR/ISO 1585 standard. The performance parameters investigated were torque, brake mean effective pressure (BMEP), brake power, specific fuel consumption (SFC), and thermal efficiency. Carbon monoxide (CO), carbon dioxide (CO₂), hydrocarbons (HC) and oxides of nitrogen (NO_X) exhaust emissions levels are also presented. The results showed that torque and BMEP were higher when the gasoline-ethanol blend was used as fuel on low engine speeds. On the other hand, for high engine speeds, higher torque and BMEP were achieved when hydrous ethanol fuel was used. The use of hydrous ethanol caused higher power at high engine speeds, whereas, for low engine speeds, both fuels produced about the same power. Hydrous ethanol produced higher thermal efficiency and higher SFC than the gasoline-ethanol blend throughout all the engine speed range studied. With regard to exhaust emissions hydrous ethanol reduced CO and HC, but increased CO₂ and NO_X levels.     

Combustion and emissions behavior for ethanol–gasoline blends in a single cylinder engine

This paper investigates the effect of using gasoline–ethanol mid-level blends (0–20% ethanol) on engine performance and exhausts emissions on a single cylinder engine by AVL model 5401, spark ignited and electronically controlled with DOHC. Engine tests were conducted for different lambda values, brake power and brake specific fuel consumption, while exhaust emissions were analyzed for carbon monoxide, unburned hydrocarbons and nitrogen oxides. Using blends at different proportions for a steady state of 2000 rpm at partial charge minimizing load and speed variations at a minimum in order to prevent them from being a measurable factor. Results showed that at constant mass fuel rates, the increase in burning rate associated with ethanol is tempered by the process combustion speed reduction related to the enleanment proportional to the ethanol added to gasoline. Blends up to 10% have marginal effects in combustion rates when compared to non-oxygenated fuels, but for 20%, combustion process slows down and increases cyclic dispersion in the results, the effect in fuel consumption observed was lower than predicted by the reduction of energy content in the gasoline, suggesting positive effects in combustion efficiency.     

A simple model to assess the contribution of alloyed and non-alloyed platinum and tin to the ethanol oxidation reaction on Pt-Sn/C catalysts: Application to direct ethanol fuel cell performance

A simple model is proposed to evaluate the contribution of alloyed and non-alloyed platinum and tin to the ethanol oxidation reaction on Pt-Sn/C catalysts for direct ethanol fuel cells. On the basis of the model, the ethanol oxidation on partially alloyed catalysts occurs through a dual pathway mechanism, separately involving the Pt₃Sn phase and Pt-SnO_x. The model, validated by experimental data, can predict the performance of a single direct ethanol fuel cell by varying the Sn content and/or the degree of alloying of Pt-Sn/C catalysts used as the anode material.     

Testing a Vapour‐fed PBI‐based Direct Ethanol Fuel Cell

This work is focused on the application and performance of a high temperature PBI‐based direct ethanol fuel cell, studying the influence of some operating variables such as the temperature, ethanol concentration and oxygen partial pressure. An increase in the temperature resulted in an improvement of the cell performance due to the enhanced electrodic kinetic and electrolyte conductivity. An ethanol/water weight ratio between 0.25 and 0.5 was found to be suitable for providing both enough water and fuel availability to make the ethanol oxidation possible. Measurements of the ethanol crossover at different temperatures and concentrations were carried out. An intermittent lifetime test showed that the cell, after several hours, was able to reach stability. Moreover, its performance was completely reversible with no perceptible losses for 7 days. Finally, tests using bio‐ethanol as fuel were performed, with no significant power losses. This final feature is of special interest from a practical ‘green' point of view.     

EIS study of corrosion behavior of metallic materials in ethanol blended gasoline containing water as a contaminant

In the present paper, the effects of ethanol as a gasoline additive and water as a contaminant on the corrosion behavior of metallic components of a fuel delivery system were investigated. Electrochemical impedance spectroscopy (EIS) testing was performed in both water-free and water contaminated gasoline containing 0%, 5%, 10% and 15% ethanol without the addition of any supporting electrolyte. The surface of the specimens examined in 10% ethanol blended gasoline was observed by scanning electron microscope to understand what types of corrosion attack occurred. The results revealed that the addition of ethanol to gasoline fuel decreased the solution resistance and polarization resistance values of the specimens, resulting in an increase in the corrosion rates of these specimens in ethanol blended gasoline. Water contaminant caused a decrease in the polarization resistance of the ferrous specimens, whereas the observed behavior in others was reversed. Among the investigated metallic materials, the brazing alloy fared the best while Al 6061 alloy showed satisfactory corrosion resistance compared to the rest of the materials in both water-free and water-contaminated ethanol blended gasoline. Moreover, no localized attack was observed in corrosion products.     

Cold start and fuel consumption of a vehicle fuelled with blends of diesel oil–soybean biodiesel–ethanol

Fuel consumption and cold start characteristics of a production vehicle fuelled with blends of N. 2 diesel oil (500 ppm sulfur content), soybean biodiesel (3%, 5%, 10%, and 20%) and hydrous ethanol (2% and 5%) were compared. A wagon-type vehicle equipped with a four-cylinder, 1.3-l, 63 kW diesel engine was tested in a cold chamber at the temperature of −5 °C for the cold start tests. Fuel consumption tests were performed following the 1975 US Federal Test Procedure (FTP-75). The results showed that the cold start time was satisfactory for all fuel blends tested, but it was longer for the blend containing 20% of soybean biodiesel (B20) in comparison with the blends with lower biodiesel concentration. The cold start time also increased with increasing with increasing ethanol content in the fuel blend. Specific fuel consumption was not affected by increasing biodiesel concentration in the blend or by the use of 2% of ethanol as an additive. However, the use of 5% of ethanol concentration in the B20 blend resulted in increased specific fuel consumption.