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291.
ABSTRACT

Renewable 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   
292.
实用厨房油雾净化方法   总被引:17,自引:0,他引:17  
通过对过滤材料的实验,研究了几种过滤材料对厨房油雾的净化性能并建立了新型的过滤材料的布置方式。  相似文献   
293.
油田压裂返排液处理技术实验研究   总被引:1,自引:1,他引:1  
油气井压裂作业过程中产生的压裂返排液已成为当前油田水体的主要污染源之一。文章对吉林油田公司压裂返排液处理工艺进行了实验研究。结果表明:在采用絮凝、微波强氧化、活性炭毡处理、纳滤/反渗透集成处理工艺后,压裂返排液CODCr可以达到GB 8978-1996《污水综合排放标准》一级标准要求。该研究为压裂返排液处理装置的设计和现场实施提供了实验基础。  相似文献   
294.
植物油燃料研究概述   总被引:7,自引:0,他引:7  
本文介绍了植物油作燃料的研究历史以及试验研究状况,表明植物油作为柴油的替代品是最易实现的方案。但植物油燃料还需进一步试验研究才能使其实用化,其技术储备具有深远的现实意义。本文还通过对燃料油植物栽培问题的探讨,认为“农林复合经营”是生产植物燃料油的重要途径。  相似文献   
295.
Long-chain fatty acid carbohydrate esters (FACE) were synthesized by the acid chloride-pyridine reaction to different degrees of substitution (DS). The hydrolyzed soybean oil was used as the source of unsaturated fatty acids. High molecular weight FACE polymers are insoluble in common solvents, such as benzene, toluene, THF, etc., and are highly water resistant. However, FACE polymers of hydrolyzed cellulose (MW 180 kD) are soluble/swellable in toluene and can be cast into tough, flexible films. FACE polymer properties of tensile strength and clasticity vary with degree of substitution and polymer size.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.  相似文献   
296.
催化裂化废水萃取脱酚预处理研究   总被引:3,自引:0,他引:3  
选用焦化粗柴油为萃取剂,对催化裂化含酚废水进行脱酚预处理,结果表明,最佳萃取条件为:pH7.0-8.5,温度15-40℃,油水体系比1.7-2.1,理论萃取级数4-7级。在上述条件下,出水酚质量浓度为50mg/L。萃取后的粗柴油用于炼油厂加氢精制装置。  相似文献   
297.
ABSTRACT: The Upper Colorado River Basin contains appreciable amounts of undeveloped fuel resources. Large quantities of oil shale, coal, and uranium have attracted recent economic and commercial interests. Development of these resources and subsequent conversion to alternative energy forms require an adequate supply of water. Water use for large scale energy development will place increasing demands on an already overstressed allocation of Colorado River water. Present water quality is at a concentration where increased salinity will result in economic detriments to holders of downstream water rights. The salt and water exchange in mining, processing, and spent fuel disposal processes has been incorporated as part of a two-level minimum cost linear programming algorithm. Mathematical simulation results provide an optimal use of Upper Colorado River water for levels of energy output such that salinity concentrations are maintained below predetermined levels.  相似文献   
298.
ABSTRACT: This paper discusses the consumptive water needs of the various energy conversion processes including oil shale retorting, coal gasification and liquefaction, electric power generation, and slurry pipelines. Projected energy development water needs in the upper Colorado River and Upper Missouri River basins are compared with projected agricultural needs and water available. The comparative cost and values of water to energy and agricultural development are discussed to emphasize this as well as the political and social factors entering into the picture.  相似文献   
299.
云南木本食用油料资源及其开发   总被引:2,自引:0,他引:2  
食用油料木本化对我国具有重要的战略意义。云南具有丰富多彩的木本食用油料树种,本文记述了云南具有重要开发价值的32 科84 种食用油料树种,并提出了它的三个开发利用的方向。  相似文献   
300.
Soybean polyols prepared by ring opening reactions of epoxidized soybean oil with hydrogen active compounds (water, alcohols, organic or inorganic acids, thiols, hydrogen etc.) have a low reactivity in the reaction with isocyanates because the hydroxyl groups are secondary. This paper presents a simple and convenient method to increase the reactivity of soybean polyols with secondary hydroxyl groups by ethoxylation reactions with the preservation of triglyceride ester bonds. The method uses mild reaction conditions: low alkoxylation temperature of 35–45 °C, low pressure of 0.1–0.2 MPa (15–30 p.s.i.) and a superacid as catalyst (HBF4). The new soybean polyols have a higher reactivity toward isocyanates in polyurethane formation due to the high percentage of primary hydroxyl groups. The primary hydroxyl content was determined by the second order kinetics of polyol reaction with phenyl isocyanate.  相似文献   
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