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91.
文章对柴油机替代燃料生命周期环境影响的评价,建立了油水煤浆燃料的评价模型,通过计算分析结果表明,随着油水煤浆中煤炭含量的增加,除光化臭氧形成潜能降低以外,其它污染指标值都有增加,说明油水煤浆系统比柴油系统消耗能量要多,对全球环境有一定影响,但在局部条件下与燃油相比,燃用油水煤浆可以减少NOX等主要污染物的排放量。  相似文献   
92.
利用生命周期评价工具对煤基M100和FTD作为车用替代燃料生命周期环境影响进行评价。结果表明:温室效应和不可再生资源消耗为两种燃料生命周期产生最主要环境影响。与M100相比,相同功能单位FTD环境影响总水平值略高。通过敏感性分析,建议综合利用CO2捕集技术等方法来减少温室气体排放。  相似文献   
93.
废聚苯乙烯的化学回收方法   总被引:10,自引:0,他引:10  
刘以荣 《化工环保》1998,18(6):332-337
废聚乙烯(PS)转化为燃料油和化学品的化学回收方法,分为废PS单独裂解及废PS与其它废塑料混合裂解两种方式,分别阐述了两种回收方式的研究成果和工艺现状,并就存在的问题进行了讨论。  相似文献   
94.
柴油机SCR催化器载体结构参数优化   总被引:2,自引:1,他引:1  
提出一种柴油机选择催化还原(SCR)催化器载体结构参数优化的设计方法,根据车用柴油机排量,将SCR催化器载体分为4类,选取载体体积、长度、目数、壁厚和涂层厚5个结构参数为设计变量,以高NO。转化率及低压力损失为优化目标,利用拉丁超立方实验设计选择样本点进行数值模拟,在构建的Kriging近似模型基础上,对载体结构参数采用改进的非支配排序遗传算法NSGA—II(non—dominatedsortinggeneticalgorithm—II)进行优化设计。结果表明:Kriging近似模型的拟合精度较高,结合NSGA—II算法对SCR催化器载体结构参数进行优化是可行的、有效的,不同排量下的优化结果均能够较好地满足设计要求。  相似文献   
95.
In this study, methanol and organometallic MnO2 fuels were used to improve the properties of diesel fuel. In addition, the effect of methanol fuel on engine oil and a piston ring was also examined experimentally in a four-cylinder, direct injection diesel engine running at 200 bar. Three different diesel fuels were prepared by adding 5, 10 and 15% methanol to diesel fuel. In order to prevent phase separation, 1% dodecanol was added to the mixture. Organometallic compounds of manganese were synthesised to prepare the solutions. The most effective amount and performance of anti-freeze were determined. From the results, it was observed that carbon monoxide emissions decreased and NOx emissions increased with the increase in the amount of methanol. On the other hand, organometallic MnO2 increased the cetane number and decreased the freezing point, viscosity and flame temperature.  相似文献   
96.
为实现对柴油机碳烟和NOx的低温同步去除,采用柠檬酸络合法制备分子筛负载钙钛矿型金属复合氧化物催化剂,应用x衍射分析仪(XRD)和电镜扫描仪(SEM)对催化剂性能进行表征,并在微型固定床反应器中对催化剂低温去除碳烟和NOx进行活性评价。利用程序升温反应(TPR)技术,进行催化剂活性评价、柴油机负荷和排放等特性实验。结果表明,A位用适量Ce部分取代La,B位用适量cu部分取代Mn,可使碳颗粒燃烧温度降低,CO2选择性好,NOx转化率升高。La0.4 Ce0.6 Cu0.2 Mn0.8O3/HZSM-5催化剂的最大NOx转化率为81.0%,Ti、Tm和Tf分别为250、350和475℃,表明该催化剂具有较好的催化活性,能在低温条件下去除碳烟和NOx。  相似文献   
97.
In this study, the top surfaces of piston and valves of a four-strokes and direct-injection diesel engine have been coated—with no change in the compression ratio—with a 100 μm of NiCrAl lining layer via plasma spray method and this layer has later been coated with main coating material with a mixture of 88% of ZrO2, 4% of MgO and 8% of Al2O3 (400 μm). Then, after the engine-coating process, ultra-low sulfur diesel (ULSD) as base fuels and its blend with used frying cottonseed oil derived biodiesel in proportion of 20%, volumetrically, have been tested in the coated engine and data of combustion and performance characteristics on full load and at different speeds have been noted. The results, which were compared with those obtained by uncoated-engine operation, showed that thermal efficiency increased, and engine noise reduced. Cylinder gas pressure values obtained from the diesel engine which has been coated with thermal barriers have been found to be somewhat higher than those of the uncoated-engine. Also, maximum pressure values measured in both engines and under the same experimental conditions through the use of test fuel have been obtained after TDC. Moreover, heat release rate and heat release have occurred earlier in the coated-engine. NOx emissions were increased while CO and HC emissions were remained almost the same with a little bit decrease.  相似文献   
98.
The increasing demand on energy due to population growth and rising of living standards has led to considerable use of fossil fuels which has in turn, had an adverse impact on environmental pollution and depletion of fossil fuels in Internal Combustion (IC) engine sector. Alternative fuel blend evaluation in IC engine fuel technologies is a very important strategic decision involving decisions balancing within a number of criteria and opinions from different decision maker of IC engine experts. The selection of appropriate source of biodiesel and proper blending of biodiesel plays a major role in alternate energy production. This paper describes an application of hybrid Multi Criteria Decision Making (MCDM) technique for the selection of optimum biodiesel blend in the IC engine. The proposed model, Analytical Network Process (ANP) is integrated with Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) to evaluate the optimum blend. Here the ANP is used to determine the relative weights of the criteria, whereas TOPSIS is used for obtaining the final ranking of alternative blends. An efficient pair-wise comparison process and ranking of alternatives can be achieved for optimum blend selection through the integration of ANP and TOPSIS. The obtained preference order for the blends are as B20 > B40 > Diesel > B60 > B80 > B100. This paper highlights a new insight into MCDM techniques to evaluate the best fuel blend for the decision makers such as engine manufactures and R&D engineers to meet the fuel economy and emission norms to empower the green revolution.  相似文献   
99.
利用便携式排放测试系统(PEMS)对一艘港作拖轮船进行了在变工况航行作业下的排放试验,研究了该船舶CO、碳氢化合物(THC)和NOx的瞬态特性、颗粒物粒径分布特性、主机在不同工况下的排放因子.结果表明:拖轮主机在日常航行工况和不同发动机负荷下,颗粒物排放粒径呈单峰或双峰分布,第一峰值粒径在30~40nm之间,第二峰值粒径为191.1nm;CO和THC在进港返航工况下基于油耗排放因子显著高于其他工况,NOx、颗粒物(PM)和颗粒物数量(PN)在离港返航时排放因子高于其他工况;各排放污染物在正顶作业时基于距离的排放因子高于其他工况;CO和THC基于功率的排放因子在正顶作业工况下最高,最高值分别为4.10和1.20g/(kW·h),NOx、PM、PN排放因子在倒拖作业工况下最高,最高值分别为10.28g/(kW·h),0.28g/(kW·h)和13.97×1014个/(kW×h).  相似文献   
100.
为进一步优化柴油机燃烧过程,减少燃烧污染物排放.围绕EGR(exhaust gas recirculation,废气再循环技术)废气组分和废气温度等系统参数对柴油机燃烧特征的影响机制,采用试验与模拟相结合方法,分别研究了通入废气、N2、CO2时以及不同EGR废气温度时对柴油机燃烧过程的影响,阐明了燃烧关键中间产物的生成规律.结果表明,①通入CO2时,柴油机的缸内最大爆发压力和放热率峰值最低,滞燃期最长,燃烧持续期最短,·OH、H2O2、CH2O·和CO等关键中间组分的生成规律与通入N2时相反.②通入N2时,柴油机的缸内最大爆发压力和放热率峰值最高,滞燃期最短,燃烧持续期最长并;并且通入N2时,·OH的峰值最高,形成时刻最早,H2O2、CH2O·以及CO的峰值均有所降低且形成时刻提前.③随着废气温度增加,缸内最大爆发压力降低,放热率曲线由单峰向双峰分布发展,放热率峰值有较大幅度的降低,滞燃期缩短,燃烧持续延长,缸内·OH、H2O2、CH2O·以及CO的峰值均有所降低,并且生成的区域范围变窄.④废气成分中,CO2对燃烧过程和关键中间产物的影响最大,是阻滞燃烧反应的主要气体成分,通过控制EGR废气成分和温度可以有效改善柴油机燃烧过程,拓宽EGR技术的工况使用范围.研究显示,EGR废气成分对燃烧中间产物的自由基衍化历程影响较大,有必要进一步开展EGR废气成分预处理研究,精确控制EGR废气温度,有助于改善燃烧过程,控制排放污染物中间产物的生成历程和排放量.   相似文献   
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