机械搅拌制备柴油-甲醇-水乳化燃料的研究

探讨了用机械搅拌法制备柴油－甲醇－水复合乳化燃料的机理，认为乳化过程是在强制对流作用下的强制混合过程，是主体对流扩散和涡流扩散两种扩散机理综合作用的结果，但混合速度取决于涡流扩散的速度。对采用SG－2乳化剂在机械搅拌乳化装置上配置柴油－甲醇－水复合乳化液的工艺进行了试验研究，结果表明，搅拌槽的挡板，搅拌器的叶轮转速，搅拌时间，乳化剂含量和甲醇中的含水量等参数对乳化液的稳定性有重要的影响。     

CLZ微乳化乙醇柴油混合燃料的发动机性能研究

基于亲油-亲水平衡(HLB值)理论和乳化原理,研究了单试剂和复合试剂作为乳化剂对乙醇柴油混合燃料体系的乳化效果和稳定性的影响,开发了一种以生物油、蓖麻油以及其他几种单试剂复配而成的CLZ复配型乳化剂,结果表明:CLZ复配型乳化剂较好地解决了E10乙醇柴油体系在较宽广温度范围内的物理稳定性问题,对E15乙醇柴油混合体系有较强的乳化能力,能使乙醇柴油混合燃料长期保持良好的物理稳定性.通过试验对比研究了乙醇柴油燃料对柴油机性能的影响,结果表明:燃用乙醇柴油混合燃料后,当量燃油消耗率降低,有效热效率提高,CO排放量低负荷时升高、高负荷时下降;NOx排放量略低于燃用纯柴油水平;THC排放量高于燃用纯柴油水平,碳烟排放量相比纯柴油大幅度下降.     

柴油乳化液的制备及其稳定性能研究

本文介绍采用多次乳化实验筛选的以Span、Tween系列为主的复配乳化剂,进行柴油掺水3%～20%乳化,减少了乳化剂用量.着重介绍选取非离子型乳化剂的PIT法.详细分析影响柴油乳化液稳定性的因素.结果表明:采用适宜配方的复合乳化剂及正确的乳化工艺,可以显著提高乳化液的稳定性,低成本快速生产优质乳化液.     

柴油-甲醇乳化燃料乳化剂的最佳HLB值及水含量的影响

柴油机中掺烧醇的最大难点之一在于难以获得价廉、稳定的柴油-甲醇乳化燃料。作者研究了柴油-甲醇乳化燃料乳化剂的最佳HLB值以及不同含水量对最佳HLB值的影响。研究结果表明：柴油-甲醇乳化燃料乳化剂的最佳HLB值在3．5左右，当柴油甲醇乳化燃料中含水形成了甲醇-水-柴油三元乳化燃料时，其最佳HLB值与柴油-水的最佳HLB值相同，且三元乳化燃料乳化剂的最佳HLB值不随含水量的增加而变化，但随着含水量增加，乳化燃料分层时间会产生变化；在柴油-甲醇-水乳化液中，当水在甲醇-水混合液中的比例为40％左右时，甲醇-水-柴油三元乳化燃料(柴油：甲醇 水=8：1)的分层时问最长，即在柴油-甲醇乳化燃料中加水有利于提高乳化燃料的稳定性。     

生物柴油-生物质油乳化燃料最佳HLB值研究

生物质油是生物质快速热解液化的产物,与生物柴油乳化后可得到一种新的可再生清洁燃料.利用超声波乳化装置制备生物柴油-生物质油乳化燃料,首先采用亲油亲水平衡(HLB)值法确定了生物柴油-生物质油乳化燃料乳化剂的最佳HLB值,然后研究了乳化燃料制备过程中各种乳化条件对乳化燃料稳定性的影响.结果表明,生物柴油-生物质油乳化燃料乳化剂的最佳HLB值为4.3～4.7,乳化时间、乳化温度、生物质油浓度及乳化剂浓度等对乳化燃料的稳定性均有一定的影响.     

机械乳化法配制乙醇柴油的探讨

随着石油资源的逐渐枯竭以及环境污染的加重，乙醇柴油逐渐被世界各国所重视。然而由于乙醇与柴油性质的不同而很难互溶。因此如何使柴油和乙醇形成均匀稳定的乳化液尤为重要。文章重点对利用机械混合乳化法配制乙醇柴油进行了探讨性研究。结果表明：利用机械的方法，通过混合乳化器的混合乳化作用，可以形成均匀稳定的乳化液，并且在汽车上进行了使用，环境效果良好，使用E5和E8动力性与柴油相当。     

乙醇/生物柴油/柴油混合燃料试验研究

对不同掺混比下乙醇/生物柴油/柴油(EBD)混合燃料的理化特性及互溶稳定性进行了试验研究。为了确定不同EBD混合燃料雾化性能的差异,基于电控喷射系统,利用马尔文法、高速摄像法研究了不同掺混比、喷射压力及喷油脉宽对燃油宏观和微观喷雾特性的影响。试验结果表明:在生物柴油/柴油混合燃料中添加乙醇,可显著改善混合燃料的雾化品质;在乙醇/柴油混合燃料中掺入生物柴油,又可显著改善混合燃料的互溶稳定性,能够满足车辆行驶需求。E10B25混合燃料的喷雾特性最佳。     

生物油/柴油乳化燃料用于柴油机的试验研究

为研究生物油/柴油乳化燃料作为柴油机燃料的性能,通过添加适量乳化剂配制成乳化燃料并在柴油机上燃用,分析了乳化燃料的燃烧特性、经济性、排放特性及对柴油机的影响.结果表明:生物油与柴油可以通过乳化形成较稳定的乳化燃料且可将其用于柴油机,但燃油消耗率比柴油高,热效率比单一柴油低;CH和CO排放增加,NO_x排放降低;使用一段时间后,供油管路中的橡胶密封件出现溶胀效应,排放因喷油器被磨蚀而随时间呈非正常变化.试验对进一步研究生物油在柴油机上的应用具有重要意义.     

柴油机燃用二甲醚-乳化柴油混合燃料的排放试验研究

研究了在柴油机上燃用二甲醚(DME)-乳化柴油混合燃料的排放特性,分析了在乳化柴油中添加DME能降低柴油机废气排放的机理,并且与燃用柴油以及乳化柴油时的排放效果进行了比较。研究结果表明:在乳化柴油中添加10%含量的DME能显著降低NOx和烟度的排放,尤其是在高负荷时,能明显降低HC和CO的排放。与燃用乳化柴油相比,即使在部分负荷时,也不会对NOx排放产生不良的影响。     

生物质热解生物油与柴油乳化的试验研究

通过生物质热解生物油模型化合物与柴油乳化的研究确定了乳化剂合适的HLB范围,在该范围内稻壳热解生物油与柴油的乳化效果良好,同时研究了生物油贮存时间对乳化效果的影响。在柴油、乳化剂和生物油质量分数分别为92%、3%和5%,试验研究了不同种类生物质热解生物油与柴油的乳化性能,乳化燃料在热值上接近柴油,粘度符合国家轻柴油标准,具有商业应用的可能。最后通过生物油和柴油乳化的三组分相图分析了形成稳定乳液时三组分的相对含量变化。     

生物油/柴油乳化燃料的稳定性及理化性质

利用非离子表面活性剂复配,对热解生物油/柴油混合液进行一系列乳化实验,测量乳化油的密度、热值、pH值.以乳化油的稳定性为实验指标,研究乳化剂种类、乳化剂用量、生物油含量对乳化油稳定性的影响.实验结果表明:在乳化温度为40℃(水浴),乳化时间为30min的条件下,以2%用量的Span80和Tween80复配乳化剂乳化生物油含量为20%的生物油/柴油混合液效果最佳.另外,随着生物油含量的增加,乳化油密度逐渐增加,热值与pH值逐渐减小.     

乳化柴油的应用研究

采用HLB值法进行筛选，复配出乳化效果和稳定性均较好的三种混合乳化剂。将乳化剂按1％、水20％掺入纯柴油，采用乳化剂在油中法，手工振荡制备出的油包水型乳化柴油，其稳定时间可达1个月。经过大量的台架试验表明：配制的乳化柴油与原纯柴油相比，平均节油率超过10％，主要排放物NOx降低超过10％、碳烟降低50％以上。     

Impact of Carbon Nanotubes and Di-Ethyl Ether as additives with biodiesel emulsion fuels in a diesel engine – An experimental investigation

In the current global energy scenario, fossil fuels face challenges with regards to exorbitant demand, environmental hazards and escalating costs. In this regard, the technical community is in quest for alternative resources. In this context, biodiesel fuel is potentially considered as alternative fuels for compression ignition engines. Hence, in this current investigation, biodiesel and biodiesel emulsions are prepared from a vegetable oil and further subjected for the blending with potential additives such as CNT (Carbon Nanotubes) and DEE (Di-Ethyl Ether) to improve the working attributes of the diesel engine. The entire investigation was carried out in five stages. In the first stage, both pure diesel and biodiesel (derived from jatropha oil) fuels were tested in the diesel engine to obtain baseline readings. In the second stage, water–biodiesel emulsion fuel was prepared in the proportion of 91% of biodiesel, 5% of water and 4% of emulsifiers (by volume). In the third stage, 50 ppm of CNT, 50 ml of DEE and combined mixture of CNT+DEE (50 ppm CNT+50 ml DEE) were mixed with the water–biodiesel emulsion fuel separately to prepare the CNT and DEE blended water–biodiesel emulsion fuels respectively. In fourth stage, the prepared emulsion fuels were subjected to stability investigations. In the fifth stage, all the prepared stable emulsion fuels were subjected for experimental testing in a diesel engine. It was observed that the CNT and DEE blended biodiesel emulsion fuels reflected better performance, emission and combustion attributes than that of pure diesel and biodiesel. At the full load, the brake thermal efficiency, NO and smoke emission of CNT+DEE fuels was 28.8%, 895 ppm and 36%, whereas it was 25.2%, 1340 ppm and 71% for pure diesel respectively. It was also observed that on adding CNT and DEE with the biodiesel emulsion fuels, the ignition delay was shortened and henceforth, the additive blended biodiesel emulsion fuels exhibited higher brake thermal efficiency and reduced emissions (NO, smoke) than that of pure diesel and biodiesel.     

Study on the spray characteristics of methyl esters from waste cooking oil at elevated temperature

In Taiwan, millions of tons of waste cooking oil are produced each year, and less than 20% of it, about 150,000 ton/a, is reclaimed and reused. Most waste oil is flushed down the drain. Utilizing waste cooking oil to make biodiesel not only reduces engine exhaust gas pollution, but also replaces food-derived fuels, and reduces ecologic river pollution. This study employed two-stage transesterification to lower the high viscosity of waste oil, utilized emulsion to reduce the methyl ester NOx pollution, and used methanol to enhance the stability and viscosity of emulsified fuel. To further analyze spray characteristics of fuels, this experiment built a constant volume bomb under high temperature, used high speed photography to analyze spray tip penetration, spray angle, and the Sauter mean diameter (SMD) of fuel droplets, and compared the results with fossil diesel. The experimental results suggested that, two-stage transesterification can significantly lower waste oil viscosity to that which is close to fossil diesel viscosity. At a temperature above 300 °C, waste cooking oil methyl esters had a water content of 20%, spray droplet characteristics were significantly improved, and NOx emission dropped significantly. The optimal fuel ratio suggested in this experiment was waste cooking oil methyl ester 74.5%, methanol 5%, water 20%, and composite surfactant Span–Tween 0.5%.     

一种新型柴油-水微乳化油的研究

本文介绍一种新颖的柴油-水微乳化燃料的研制及其在柴油机上应用的试验研究。试验结果表明,这种新颖微乳化燃料在柴油机上应用是可行的,发动机的动力性、经济性良好,运转平稳,特别是在中、低负荷时,发动机的有效热效率比燃用纯柴油时高。发动机排气温度和烟度明显降低,排放指标也在一定程度上得到了改善。     

适合柴油—甲醇—水复合乳化的新型乳化剂研究

介绍了一种适合于柴油-甲醇-水复合乳化的高分子乳化剂的制取方法,对该种乳化剂的乳化过程进行了机理和试验研究,试验结果表明,用该种乳化剂配制的乳液稳定时间长,而乳化剂的用量比较低。探讨了用CR-2型乳化装置配制柴油-甲醇-水复合乳液的工艺,并在柴油机试验台架上考察了用该种乳化剂配制的乳液的适应性。     

Emission analysis of diesel engine fueled with soybean biodiesel and its water blends

The present study is carried out to formulate stable water-in-soybean biodiesel emulsion fuel and investigate its emission characteristics in a single cylinder diesel engine. Four types of emulsion fuels, which consist of a different percentage of water (5%, 10%, 15%, and 20%) in soybean biodiesel, were prepared with suitable surfactant and properties were measured. The physicochemical properties are on par with EN 14214 standards. The experimental result of test fuels indicates that the soybean biodiesel promotes a lower level of hydrocarbon (HC), carbon monoxide (CO) and smoke emissions compared to base diesel except for nitrogen oxide (NOx) emission. Increase in water concentration with soybean biodiesel significantly reduces the NOx emission and smoke opacity. The HC and CO emissions are further reduced with emulsified biodiesel up to 10% water concentration and beyond that limit, marginal increases are recorded. Overall, it is observed that inclusion of water with soybean biodiesel reduces the HC, CO, NOx and smoke emissions when compared to base diesel and soybean biodiesel, and 10% water in soybean biodiesel is an appropriate solution to reduce the overall emissions in the soybean-fuelled diesel engine.     

A comprehensive study on performance,emission and combustion behavior of a compression ignition engine fuelled with WCO (waste cooking oil) emulsion as fuel

This work aims at evaluating the performance, emission and combustion of a diesel engine fuelled with WCO (waste cooking oil obtained from palm oil) and its emulsion as fuel. A single cylinder water-cooled diesel engine was used. Base data was generated with diesel and neat WCO as fuels. Subsequently, WCO oil was converted into its emulsion and tested. Neat WCO resulted in higher smoke, hydrocarbon and carbon monoxide emissions as compared to neat diesel. Significant reduction in all emission was achieved with the WCO emulsion. Cylinder peak pressure and maximum rate of pressure rise were found to be higher with WCO emulsion as compared to neat WCO mainly at high power outputs. Ignition delay was found as higher with neat WCO and its emulsion. It is concluded that WCO emulsion can be used in diesel engines without any modifications in the engine with superior performance and reduced emissions at high power outputs.