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371.
土壤中矿物油含量测定方法研究 总被引:1,自引:0,他引:1
建立了土壤中矿物油含量的分析方法。采集的土壤鲜样,采用无水硫酸钠进行化学干燥。用四氯化碳提取土壤中的油类物质,采用硅酸镁去除提取液中的动植物油等极性化合物后,使用红外分光测油仪测定提取液中的矿物油含量。此方法具有良好的线性关系,相关系数在0.9999以上。测定下限为1.85 mg/l,测定上限为100 mg/l,测量范围为9 mg/kg~500 mg/kg,方法的灵敏度为1.05。试剂空白加标回收率56%~83%,实际样品加标回收率在69%~74%之间。该法简便快速,灵敏准确,具有广泛的应用前景。 相似文献
372.
船舶溢油事故的预测,是确定所需应急资源多少的重要依据;但船舶溢油事故具有小样本性,传统预测方法不再适用。针对船舶溢油事故的小样本性,该文选择SVR模型对其进行预测;SVR算法的关键是核函数的选择及自由参数的确定,针对上述问题该文分别采用交叉验证法、遗传算法;并在matlab软件上建立SVR模型,最后将该模型应用于上海港水域船舶溢油事故的预测。 相似文献
373.
《International Journal of Sustainable Engineering》2013,6(6):349-365
Alternative fuels have numerous advantages compared to fossil fuels as they are renewable, biodegradable; provide energy security and foreign exchange saving besides addressing environmental concerns and socio-economic issues as well. Renewable fuels can be used predominantly as fuel for both transportation and power generation applications. Improved engine performance with reduced engine exhaust emissions is a major research objective in engine development. Today, the use of biomass derived producer gas is more relevant for addressing rural power generation and is a promising technique for controlling both nitric oxide (NOx) and soot emission levels. In view of this, exhaustive experiments on the use of Honge oil methyl ester (HOME)–Producer gas in a dual fuel engine have been carried out with an intension of improving its fuel efficiency. This paper mainly presents results on a single cylinder four stroke direct injection diesel engine operated in dual fuel mode using HOME–Producer gas combination with and without bio-ethanol addition and thermal barrier coating (TBC). Further, the results were compared with diesel–producer gas mode of operation. Experimental investigation on dual fuel operation using HOME+5% bioethanol (BE5)–Producer gas operation with TBC showed 12.35% increased brake thermal efficiency with decreased hydrocarbon and carbon monoxide emissions and increased NOx emission levels compared to HOME–Producer gas mode of operation. 相似文献
374.
《International Journal of Sustainable Engineering》2013,6(1):55-65
The diminishing resources and continuously increasing cost of petroleum in association with their alarming pollution levels from diesel engines have caused an interest in finding alternative fuels to diesel which are renewable and sustainable. Emission control and engine efficiency are two most important parameters in current engine design. The impending introduction of emission standards such as Euro IV and Euro V is forcing the research towards developing new technologies for combating engine emissions. The classification of Euro IV and V norms is applicable to heavy-duty engines in Europe, where as Euro 5 is applicable to light-duty engines. This paper presents the effects of exhaust gas recirculation (EGR), swirl augmentation techniques and ethanol addition on the combustion of Honge oil methyl ester (HOME) and its blends with ethanol in a diesel engine. From the experimental work conducted, it is found that the combustion of HOME plus up to 15% ethanol blend in a diesel engine operated with optimised parameters of injection timing 23° Before Top Dead Centre and compression ratio 17.5 results in acceptable combustion emissions and improved brake thermal efficiency (BTE). The addition of ethanol increased BTE with reduced hydrocarbons (HCs), CO and smoke emissions. However, NO x emissions increased dramatically. Use of appropriate EGR reduces NO x to acceptable levels. The implementation of swirl augmentation techniques further resulted in increased BTE and considerable reduction in tail pipe emissions such as smoke, HCs, CO and NO x . The effect of swirl by providing grooves on the piston was taken into consideration to find the overall biodiesel engine performance, which gives scope for further studies. 相似文献
375.
《International Journal of Sustainable Engineering》2013,6(4):248-261
ABSTRACTRenewable and sustainable fuels for diesel engine applications provide energy protection, overseas exchange saving and address atmospheric and socio-economic concerns. This study presents the investigational work carried out on a single cylinder, four-stroke, direct injection diesel engine operated in dual fuel (DF) mode using renewable and sustainable fuels. In the first phase, a Y-shaped mixing chamber or venture was developed with varied angle facility for gas entry at 30°, 45° and 60°, respectively, to enable homogeneous air and gas mixing. Further effect of different gas and air mixture entry on the DF engine performance was studied. In the next phase of the work, hydrogen flow rate influence on the combustion and emission characteristics of a compression ignition (CI) engine operated in DF mode using diesel, neem oil methyl ester (NeOME) and producer gas has been investigated. During experimentation, hydrogen was mixed in different proportions varied from 3 to 12 l/min (lpm) in step of 3 lpm along with air-producer gas and the mixtures were directly inducted into engine cylinder during suction stroke. Experimental investigation showed that 45° Y-shaped mixing chamber resulted in improved performance with acceptable emission levels. Further, it is observed that investigation showed that at maximum operating conditions and hydrogen flow rate of 9 lpm, Diesel–producer gas and NeOME–producer gas combination showed increased thermal efficiency by 13.2% and 3.8%, respectively, compared to the DF operation without hydrogen addition. Further, it is noticed that hydrogen-enriched producer gas lowers the power derating by 5–10% and increases nitric oxide (NOx) emissions. However, increased hydrogen addition beyond the 12 lpm leads to sever knocking.Abbreviations: NeOME: Neem oil methyl ester; BTE: brake thermal efficiency; CI: compression ignition; ITE: indicated thermal efficiency; PG: producer gas; CA: crank angle; K: Kelvin; BP: brake power; IP: indicated power; H2: hydrogen; HC: unburnt hydrocarbon; CO: carbon dioxide; CO2: carbon dioxide; NOx: nitric oxide; HRR: heat release rate; %: percentage; PPM: parts per million; CMFIS: conventional mechanical fuel injection system. 相似文献
376.
377.
旋转压缩机油路系统仿真与试验研究 总被引:1,自引:0,他引:1
压缩机泵油系统对滚动转子压缩机性能和可靠性非常重要.为了了解压缩机泵油特性.本文应用CFD软件,采用VOF模型对滚动转子压缩机整个泵油系统进行数值模拟,搭建试验台进行试验,并将模拟和试验结果进行对比,结果表明上法兰螺旋槽处润滑油流量结果吻合很好,误差在10%以内,证明了该仿真方法的可行性. 相似文献
378.
分析总结了氧气钢瓶物理爆炸和化学爆炸的原因。针对2009年某市发生的一起氧气瓶内含油脂爆炸事故,系统分析了国内曾经发生的几次因油脂导致气瓶爆炸事故。油脂进入到氧气瓶内大都是由于误操作。油脂与高压纯氧接触会发生剧烈的自燃氧化放热,使瓶内的氧气迅速升温升压,超出气瓶承压极限导致爆炸破裂。分析比较发现由油脂导致的气瓶爆炸,其破坏程度不如混入可燃气体导致的气瓶爆炸剧烈,一般不是粉碎性爆炸。在正常的充氧过程中,氧气瓶温度会升高,采用变质量热力学中的方法,计算说明气瓶在充装过程中氧气温度的具体变化。充氧温度计算为充氧工作人员提供参考,如发现异常情况,可以及时地控制和预防。由现场压力表可知氧气瓶在充装至12MPa时发生爆炸,而氧气瓶最小爆炸压力为37.6MPa,油脂燃烧放热,计算可知致使钢瓶爆炸破裂所需要的最小油脂量,为66.4-79.6g。不同的充装压力下发生爆炸,所需要的最小油脂量不同,充装压力越高,爆炸所需要的最小油脂量越少。 相似文献
379.
伴随着石油工业的发展,井喷、井控不可避免。为防止溢流、井喷,企业、政府投入了大量的人力、物力、财力,成果显著。但同时也产生了一些副作用,过量投资,资源浪费,地层严重污染,含硫油气井更是如此。基于含硫油气井钻完井的特点,制定了含硫油气井井控工作原则,研究了包含防爆、保证防喷器可靠、保证节流放喷相关装置可靠、保证压井相关装置可靠及保证井眼力学完整在内的含硫油气井严格防止井喷失控技术,选用合适的压井方法避免发生井喷技术,简化关井操作程序及修改钻井液密度附加值来全面限制防溢流的技术及其相应的管理方法。对含硫油气井科学、安全、高效的进行井控工作提供了理论指导,对于含硫油气井的开发具有重要的意义。 相似文献
380.
介绍说明几起氧气瓶内附油脂充氧过程中爆炸事故。介绍高压氧气与油脂的反应,论述了空压机润滑油燃烧基本特性,采用热重天平进行了空压机润滑油在不同压力的气体氛围内的燃烧试验,建立起空压机润滑油的热重和微商热重曲线,得到空压机润滑油在不同压力的氧气氛围内的自燃点。放入加压热重分析仪内的润滑油,接触高压氧气后迅速被氧化,氧气压力越高,氧化程度越深。随着氧气压力的升高,润滑油的着火点降低。这表明氧气瓶中油脂,随着充氧压力的增加,着火点降低,即压力越大,油脂越容易自燃,释放热量,导致爆炸。提出安全措施。 相似文献