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在一台满足国Ⅴ排放标准的双喷射(气口喷射+缸内直喷)汽油机上开展了燃用E10乙醇汽油(乙醇体积比为10%)对发动机非常规排放特性影响的试验研究.使用傅里叶变换红外分析仪(FTIR)测量了饱和烃、不饱和烃、芳香烃及醇、醛等非常规污染物排放量,对比分析了双喷射模式时各工况下E0和E10两种燃料的非常规排放水平.结果表明,双喷射模式下,加入乙醇有效降低了乙烯、1,3-丁二烯、苯和甲苯的排放量,但会导致乙醛排放升高.双喷射模式下,随着负荷增加,两种燃料下的1,3-丁二烯和甲苯排放呈现先升高后降低的趋势,乙烯、甲醛和苯排放则先降低后升高.乙醇能抑制1,3-丁二烯、乙烯生成,抑制效果为PFI模式优于双喷射模式,GDI模式抑制量最低.PFI和GDI模式下E10的甲醛排放均显著升高,但双喷射模式有效抑制了甲醛排放的增加. 相似文献
33.
Ethanol fuels: Energy security,economics, and the environment 总被引:6,自引:0,他引:6
Problems of fuel ethanol production have been the subject of numerous reports, including this analysis. The conclusions are that ethanol: does not improve U.S. energy security; is uneconomical; is not a renewable energy source; and increases environmental degradation. Ethanol production is wasteful of energy resources and does not increase energy security. Considerably more energy, much of it high- grade fossil fuels, is required to produce ethanol than is available in the energy output. About 72% more energy is used to produce a gallon of ethanol than the energy in a gallon of ethanol. Ethanol production from corn is not renewable energy. Its production uses more non- renewable fossil energy resources in growing the corn and in the fermentation/distillation process than is produced as ethanol energy. Ethanol produced from corn and other food crops is also an unreliable and therefore a non-secure source of energy, because of the likelihood of uncontrollable climatic fluctuations, particularly droughts which reduce crop yields. The expected priority for corn and other food crops would be for food and feed. Increasing ethanol production would increase degradation of agricultural land and water and pollute the environment. In U.S. corn production, soil erodes some 18- times faster than soil is reformed, and, where irrigated, corn production mines water faster than recharge of aquifers. Increasing the cost of food and diverting human food resources to the costly and inefficient production of ethanol fuel raise major ethical questions. These occur at a time when more food is needed to meet the basic needs of a rapidly growing world population. 相似文献
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本文从我国石油能源短缺和汽车尾气污染环境加剧的背景出发,详细分析了目前主要的各种新能源汽车的特点及在我国发展的前景,最后得出乙醇汽车应是我国发展新能源汽车的最佳选择的结论。 相似文献
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Denitrification potential enhancement by addition of external carbon sources in a pre-denitrification process 总被引:3,自引:0,他引:3
The aim of this study is to investigate the denitrification potential enhancement by addition of external carbon sources and to estimate the denitrification potential for the predenitrification system using nitrate utilization rate (NUR) batch tests. It is shown that the denitrification potential can be substantially increased with the addition of three external carbon sources, i.e. methanol, ethanol, and acetate, and the denitrification rates of ethanol, acetate, and methanol reached up to 9.6, 12, and 3.2 mgN/(g VSS.h), respectively, while that of starch wastewater was only 0.74 mgN/(g VSS,h). By comparison, ethanol was found to be the best external carbon source. NUR batch tests with starch wastewater and waste ethanol were carried out. The denitfification potential increased from 5.6 to 16.5 mg NO3-N/L owing to waste ethanol addition. By means of NUR tests, the wastewater characteristics and kinetic parameters can be estimated, which are used to determine the denitrification potential of wastewater, to calculate the denitrification potential of the plant and to predict the nitrate effluent quality, as well as provide information for developing carbon dosage control strategy. 相似文献
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Biodegradation of mixture of VOC's in a biofilter 总被引:6,自引:0,他引:6
Volatile organic compounds(VOC‘s) in air have become major concern in recent years. Biodegradation of a mixture of ethanol and methanol vapor was evaluated in a laboratory biofilter with a bed of compost and polystyrene particles using an acclimated mixed culture. The continuous performance of the biofilter was studied with different proportion of ethanol and methanol at different initial concentration and flow rates. The result showed significant removal for both ethanol and methanol, which were composition dependent.The presence of either compound in the mixture inhibited the biodegradation of the other. 相似文献
40.
混燃甲醇和乙醇改善柴油机碳烟排放 总被引:13,自引:0,他引:13
以柴油机为基础,以乙醇或甲醇作为预混合燃料,与喷入的柴油组成部分预混的复合燃烧,大幅度降低了发动机排气烟度,同时使氮氧化物排放得到一定改善,发动机的燃油消耗率优于原柴油机,而HC排放,尤其是在低负荷时有所增加,甲醇比乙醇具有降低烟度效果更好、氮氧化物降低更多和HC及CO排入增加较少的优越性。 相似文献