共查询到20条相似文献,搜索用时 171 毫秒
1.
含氧添加剂DMC对柴油机燃烧与排放特性的影响 总被引:13,自引:2,他引:11
分析了各种含氧燃料的物理化学特性对柴油机排放的影响。碳酸二甲酯(DMC)具有含氧量高、沸点高、与柴渍互溶性好等特点,适合作为柴油机的燃料添加剂。测试了纯柴油和含添加剂DMC的柴油机的尾气排放,并进行了燃烧分析。结果表明:添加剂DMC能较大幅度地降低柴油机的碳烟排放,同时使NDx的排放基本保持不变或略有下降;含DMC的燃料滞燃期比纯柴油的长,且燃烧结束的时间早,热效率要比柴油的高,当DMC的添加量为15%时,在不同的工况下,热效率比纯柴渍高1%-3%。 相似文献
2.
降低NO_x排放──对船用柴油机厂家的技术挑战 总被引:2,自引:0,他引:2
20年前,造船业不那么重视空气污染问题。当联合国国际海事组织(UN-IMO)宣布2000年船舶NOx排放量要求下降30%的目标时,这种淡漠状况起了变化。个别国家正在考虑更大幅度地降低其水域中的NOX排放,IMO把降低30%仅仅看成是第1个目标。降低NOx排放的技术措施可以分成基本措施和尾气处理两种。在基本措施中,延迟喷油始点、改变压缩比、采用排气再循环。喷水和降低进气温度是最为广用的,而NOX催化转换(排气后处理)则可使其降低90%,甚至更多。IMO的1997秋季会议将通过马波罗协定的新附件VI──防止船舶的空气污染,有关的法… 相似文献
3.
奉节县氮肥厂三项节能技改技术四川奉节县氮肥厂毛嘉兴,张军1稀氨水回收技术奉节氮肥厂由于生产能力扩大,合成放空气、碳化尾气回收流程落后,为保证尾气中氨含量,只得加大软水量。生产过程中大量稀氨水过剩,未能回收利用,合成放空气未加回收,氨回收率仅30%左右... 相似文献
4.
本文针对在用汽车和摩托车化油器式汽油机尾气排放中的主要有害气体HC、CO的净化方法进行了简单的探讨,并设计了一种主要降低HC、CO的净化热反应器,在49ZQA汽油机上进行了初步对比试验。试验结果表明装净化热反应器后,尾气中的HC、CO降低50%左右,效果明显。而且该净化热反应器结构简单,成本低廉。 相似文献
5.
6.
7.
柴油机稀燃NOx催化剂的性能评价试验 总被引:4,自引:0,他引:4
如何在稀燃条件下降低柴油机尾气中的NOχ是柴油机后处理技术的难点之一。在发动机台架上对乙醇作为还原添加剂的柴油机稀燃NOχ催化剂进行了起燃特性和空速特性的性能评价,并考察了该催化剂对欧Ⅲ排放法规的适应性。结果表明:催化剂的起燃特性曲线先随温度升高而增加,后随温度升高而降低,并且整个转化率曲线随空速增加而下降;欧Ⅲ测试循环中,NOχ排放值明显降低,其转化效率达50%以上,能够满足欧Ⅲ要求.但CO和HC排放值明显升高,不能满足欧Ⅲ要求,需要采取其他措施。 相似文献
8.
本文对在LPG/汽油两用燃料汽车上加装三元催化器和电控补气装置的优化匹配过程进行了详细的介绍,加装该系统可以有效地降低尾气排放污染,使两用燃料车辆达到新的排放法规的严格要求。 相似文献
9.
对大连石化聚丙烯装置尾气排放和回收现状进行了分析,通过对全厂尾气排放管网进行优化设置,把全厂尾气中的可回收气体(主要是丙烯、丙烷等有机蒸气)和不可回收气体(主要是氮气、乙烷等不凝气)分开排放,可回收气体排人气柜。尾气升压冷凝回收后,有机蒸气回收率为89.73%,但升压冷凝后的排空气中仍含有58%左右的C3H6和C3H8,再利用膜分离技术对排空气中的有机蒸气进行回收,丙烯单体回收率达到96.21%。通过优化排空管网设置、升压冷凝回收和膜分离回收等3种技术手段的综合运用,聚丙烯装置尾气中有机蒸气的回收率达到了99.59%,避免了装置尾气排放造成的环境污染.同时优化了资源,降低了生产成本。 相似文献
10.
柴油添加剂可以降低发动机燃烧室内的碳烟生成,而微粒捕集器则能有效控制柴油机尾气中微粒排放。对柴油添加剂种类、微粒捕集器过滤体材料和微粒捕集器的再生方法分别作了介绍,并着重对柴油添加剂促进微粒捕集器再生的机理和存在的问题进行了分析和研究。 相似文献
11.
For the fuel ignition, the thermal conductivity and heat capacity are the key properties that determine the pre-ignition behavior of the drop of the fuel. The classic monophase fuels, such as natural gas, liquid propellants, or solid one-component fuels, have been investigated for a long time; and their thermophysical properties are well known in most of the cases. Composite fuels, which have recently attracted the attention of the researchers, have complex contents. In many cases, composite fuel is a mixture of solid and liquid components in the form of a slurry. Coal-water fuel and its derivatives with different additives are examples of such type fuels. For those fuels, the thermophysical properties are usually unknown. Nowadays, researchers use simple additivity theory for the calculation of the thermophysical properties of complex fuels for the first approach. Authors of this research believe that the simple additivity approach is not correct and can lead to the wrong results in the case of the numerical research of the ignition and burning processes of such a fuel. In the present research, the thermophysical properties of coal-water fuel with glycerol additives were experimentally obtained. It was found that the coefficient of thermal conductivity increases with temperature and varies in the range of 0.45 to 0.53 W/(m·K). The heat capacity of the fuel also increases with the temperature and varies from 4.7 to 5.5 kJ/kg·K. The higher the glycerol content, the lower the thermal conductivity and heat capacity of the composite fuel in the investigated temperature range. The results confirm the failure of the approach of the additivity law usage. Neither, thermal conductivity coefficient or heat capacity of the coal-water fuel with the addition of up to 20% glycerol complies with the additivity law. Differences between real values of the thermophysical properties and calculated ones are more than 30% to 50%. Empirical expressions for calculation of the thermophysical properties of coal-water fuel with the addition of up to 20% glycerol are presented. 相似文献
12.
《Energy Conversion and Management》2005,46(11-12):1731-1744
The article presents the comparative bench testing results of a naturally aspirated four stroke, four cylinder, water cooled, direct injection Diesel engine when running on shale oil that has been treated with multi-functional fuel additives. The purpose of the research is to evaluate the effectiveness of the fuel additives Marisol FT (Sweden) and SO-2E (Estonia) as well as to verify their ability to increase energy conversion and reduce brake specific fuel consumption, contamination and smoke opacity of the exhausts when fuelling the Diesel engine with shale oil.Test results show that application of these additives could be a very efficient means to improve Diesel engine performance on shale oil, especially when operating at the light load range. The brake specific fuel consumption at light loads and speeds of 1400–2000 min−1 reduces by 18.3–11.0% due to the application of the Marisol FT. The additive SO-2E proves to produce nearly the same effect.The total NOx emission from the fully loaded Diesel engine fuelled with the treated shale oil reduces by 29.1% (SO-2E) and 23.0% (Marisol FT). It is important that the lower NOx is obtained due to reducing both harmful pollutants, NO and NO2. The CO emission at rated power increases by 16.3% (SO-2E) and 48.0% (Marisol FT), whereas the smoke opacity of the exhausts increases by 35% and over 2 times, respectively. The effect of the fuel additives on the HC emission seems to be complicated and ambiguous. 相似文献
13.
Chandra Bhushan Kumar D.B. Lata Dhaneshwar Mahto 《International Journal of Hydrogen Energy》2021,46(14):9595-9612
Today, the world faces a number of challenges on global level. The optimum replacement for fossil fuels is one of these challenges. Hydrogen in the past has been and continues to be used by numerous researchers in diesel engines. However, high NOx emissions and low replacement of hydrogen fuel are the concern with many researchers. In the present study, di-tert butyl peroxide (DTBP) has been used as an additive in diesel fuel, to investigate the performance and exhaust emissions of the diesel engine working on dual fuel mode by using hydrogen as secondary fuel. At low, medium and high load conditions, the maximum increase in brake thermal efficiency was observed to be 87.50%, 14.68% and 5.89% respectively for 1%, 3% and 5% of additive (DTBP) by 40% of hydrogen fuel substitution, as compared to diesel fuel operation. Moreover, by addition of 4% di-tert butyl peroxide (DTBP) in diesel engine working on dual fuel mode showed 33.82%, 10.27% and 29.27% reduction in NOx emission at low, medium and high load conditions respectively at 40% hydrogen substitution, as compared to dual fuel operation using hydrogen as secondary fuel without additives. By addition of 5% additive (DTBP) at 69% load condition and 40% hydrogen substitution, reduces CO emissions by 38.66% as compared to dual fuel operation, using hydrogen as secondary fuel. 相似文献
14.
15.
16.
《International Journal of Hydrogen Energy》2021,46(62):31903-31915
A detailed investigation of employing landfill gas together with additives such as hydrogen or propane or both as a primary low reactivity fuel in a reactivity controlled compression ignition combustion of a diesel engine is conducted. A 3401E caterpillar single-cylinder diesel engine with a bathtub piston bowl profile is utilized to execute the study. The engine is operated at various intake pressures of 1.6, 1.9, and 2.2 bar, and runs at a fixed engine speed of 1300 rpm. For verification purposes, the conduct of the present engine running on pure methane as a low reactivity fuel is compared to that of the same engine available in the literature. Next, a numerical simulation is made to assess the performance of the present engine running on landfill gas plus the additives. Based on the obtained results, injecting either hydrogen or propane or a combination of both up to a total amount of 10% by volume to the premixed of landfill gas and air, and advancing diesel fuel injection timing of about 20–30 deg. crank angle, render the landfill gas utilization quite competitive with using methane alone. Applying an enriched landfill gas in a reactivity controlled compression ignition diesel engine, as a power generator, drastically reduces the greenhouse gas emission to the atmosphere. Also, the CO and UHC mole fraction in the exhaust gas can be eliminated by either advancing the start of diesel injection or using hydrogen or propane or both as additives. In addition, utilizing hydrogen or propane or a combination of both with the primary fuel improves the peak pressure to about 16% in comparison with that of landfill gas alone. 相似文献
17.
氢能发电技术的研究(Ⅱ)——电极添加剂对离子膜燃料电池放电性能 … 总被引:1,自引:1,他引:0
离子交换膜电池作为一种理想的氢能发电装置,是目前氢能研究开发的热点。研究了电极添加剂对离子交换膜燃料电池电化学性能的影响。 相似文献
18.
Advances in biodiesel, emulsified diesel and artificial chemical additives are driven by consumer demand to save energy and reduce emissions from diesel engines. However, the effect of emulsified bio-solution/palm-biodiesel/diesel blends in diesel engines has not been assessed. Experimental results in this work demonstrate that the emulsified bio-solution/palm-biodiesel/diesel blends have the advantage in saving energy and reducing emissions of both polycyclic aromatic hydrocarbons (PAHs) and particulate matter (PM) from diesel engines. When comparing with P0 (premium diesel fuel as base fuel), E16P20 fuel (16 vol% bio-solution + 20 vol% palm-biodiesel + 64 vol% P0, an additional 1 vol% surfactant) saved 12.4% fuel consumption and reduced emissions of PM by 90.1%, total PAHs by 69.3%, and total BaPeq (benzo[a]pyrene equivalent concentration) by 69.6%. Emulsified palm-biodiesel with bio-solution can be considered as a clean and alternative fuel. 相似文献
19.
S. Karthikeyan A. Prathima 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(24):3673-3679
The role of additives for biodiesel has gained most reliable position in the current scenario as they reasonably formulate base fuel composition that contribute to efficiency reliability and long life of an engine. They also can have surprisingly large effects even when used in low (ppm) range. With the use of fuel additives for blending the biodiesel in compression ignition engine, one can expect diminished engine exhaust emission characteristics and also improved fuel properties, which could enhance the combustion characteristics. There are many reports based on the biodiesel blended with nanoparticles additive; however, there is a vacuum in the research pertaining to the use of the most common, low-cost, and eco-friendly CeO2 nanoparticles as additive to prepare blended canola biodiesel fuel. Moreover, there are very few literatures available on the usage of CeO2 blended biodiesel. In the present study, an attempt has been made to reduce and understand the engine emission of biodiesel blended with CeO2 nanoparticles. 相似文献
20.
《International Journal of Hydrogen Energy》2019,44(12):6116-6135
Polymer electrolyte membranes, also known as proton exchange membranes (PEMs), are a type of semipermeable membrane that exhibits the property of conducting ions while impeding the mixing of reactant materials across the membrane. Due to the large potential and substantial number of applications of these materials, the development of proton exchange membranes (PEMs) has been in progress for the last few decades to successfully replace the commercial Nafion® membranes. In the course of this research, an alternate perspective of PEMs has been initiated with a desire to attain successful operations at higher working temperatures (120–200 °C) while retaining the physical properties, stability and high proton conductivity. Both low- and high-temperature PEMs have been fabricated by various processes, such as grafting, cross-linking, or combining polymer electrolytes with nanoparticles, additives and acid-base complexes by electrostatic interactions, or by employing layer-by-layer technologies. The current review suggests that the incorporation of additives such as plasticisers and fillers has proven potential to modify the physical and chemical properties of pristine and/or composite membranes. In many studies, additives have demonstrated a substantial role in ameliorating both the mechanical and electrical properties of PEMs to make them effective for fuel cell applications. It is notable that plasticiser additives are less desirable for the development of high-temperature PEMs, as their inherent highly hydrophilic properties may stiffen the membrane. Conversely, filler additives form an inorganic-organic composite with increased surface area to retain more bound water within the polymer matrices to overcome the drawbacks of ohmic losses at high operating temperatures. 相似文献