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381.
针对近年来加油站建设过程中存在的问题,剖析不合理工艺,结合实际提出加油站在新建、改造过程中应注意事项。  相似文献   
382.
Using an Integrated TerrestrialEcosystem C-budget model (InTEC), we simulated thecarbon (C) offset potentials of four alternativeforest management strategies in Canada: afforestation,reforestation, nitrogen (N) fertilization, andsubstitution of fossil fuel with wood, under differentclimatic and disturbance scenarios. C offset potentialis defined as additional C uptake by forest ecosystemsor reduced fossil C emissions when a strategy isimplemented to the theoretical maximum possibleextent. The simulations provided the followingestimated gains from management: (1) Afforesting allthe estimated 7.2 Mha of marginal agricultural landand urban areas in 1999 would create an average Coffset potential of 8 Tg C y-1 during 1999–2100,at a cost of 3.4 Tg fossil C emission in 1999. (2)Prompt reforestation of all forest lands disturbed inthe previous year during 1999–2100 would produce anaverage C offset potential of 57 Tg C y-1 forthis period, at a cost of 1.33 Tg C y-1. (3)Application of N fertilization (at the low rate of 5kg N ha-1 y-1) to the 125 Mha ofsemi-mature forest during 1999–2100 would create anaverage C offset of 58 Tg C y-1 for this period,at a cost of 0.24 Tg C y-1. (4) Increasingforest harvesting by 20% above current average ratesduring 1999–2100, and using the extra wood products tosubstitute for fossil energy would reduce averageemissions by 11 Tg C y-1, at a cost of 0.54 TgC y-1. If implemented to the maximum extent, thecombined C offset potential of all four strategieswould be 2–7 times the GHG emission reductionsprojected for the National Action Plan for ClimateChange (NAPCC) initiatives during 2000–2020, and anorder of magnitude larger than the projected increasein C uptake by Canada's agricultural soils due toimproved agricultural practices during 2000–2010.  相似文献   
383.
甲醇燃料汽车排气净化   总被引:1,自引:0,他引:1       下载免费PDF全文
在燃用纯甲醇(M100)的BJ492Q型四冲程发动机的台架试验中,用堇青石蜂窝金属钯催化剂进行了排气净化试验。在发动机的混合比调整和负荷特性试验条件下观察了排气中甲醇、甲醛和一氧化碳的净化效果,观察了发动机的怠速起动和暖机过程中催化剂的净化性能。结果表明,发动机排气经催化净化后,排气中甲醇、甲醛和一氧化碳的浓度分别降低到3—17ppm,1—13ppm和0.01—0.30%;净化率分别达到93—99%,92—98%和80—99%。在发动机怠速起动和暖机过程中催化剂可点燃发挥净化作用。制作了催化箱,在武汉213型越野客货车上初步考察了其实用性能。  相似文献   
384.
“三合一”微生物燃料电池的产电特性研究   总被引:34,自引:0,他引:34  
曹效鑫  梁鹏  黄霞 《环境科学学报》2006,26(8):1252-1257
为了降低内阻,尽可能提高微生物燃料电池的输出功率,提出了一种将阳极、质子交换膜和阴极热压在一起的"三合一"膜电极形式的微生物燃料电池,并考察了其在接种厌氧污泥条件下对乙酸自配水的产电特性.该"三合一"电池在稳定运行条件下电池内阻约为10~30Ω,远低于现已报道的其它形式的微生物燃料电池的内阻.目前该"三合一"型微生物燃料电池最大输出功率密度约300 mW·m-2,库仑效率约50%.试验结果表明,在一个间歇运行周期中,电池内阻增加是引起输出电压降低的最主要原因.同时在不同的外阻条件下,需要降低极化的重点不同.  相似文献   
385.
蒋利桥  赵黛青  何立波 《环境科技》2006,19(3):17-19,23
综合分析了含氧替代燃料的来源、成份和燃烧后尾气排放特性.着重阐述了含氧替代燃料应用中污染物排放特点:虽然含氧替代燃料燃烧过程中二氧化硫、一氧化碳、炭氢化合物和煤烟等常规污染物排放明显降低,但醇和醛类等非常规污染物排放会明显增加,这些非常规污染物的排放及环境影响在国内还没有引起足够的重视,需要对含氧替代燃料应用过程中非常规污染物的排放特性及抑制机理进行更深入的研究。  相似文献   
386.
生物质燃料的利用现状与展望   总被引:6,自引:0,他引:6  
分析了生物质燃料作为可持续发展的能源利用的前景,从固态、液态和气态3种燃料的状态,介绍了国内外生物质燃料的利用形式,对生物质燃料的商品化和大规模利用进行了展望。  相似文献   
387.
标准系列加入回归法测定燃油中微量氮   总被引:1,自引:0,他引:1  
对燃油中含氮量的测定方法进行了研究,提出了一种分析测定燃油中微量氮的简便方法。在待测柴油中加入一系列不同体积的吲哚标准溶液后,让油样在亚硒酸催化作用下,经浓硫酸预消解——稀硫酸回流消解、碱性条件下蒸馏及馏出液用稀硫酸接收,使其中的有机氮变为无机氮,继而转化成为可分析试样,最后用麝香草酚比色法一线性回归法算出柴油中的总氮。该分析方法的回收率在98.0%~100.2%之间,相对标准偏差小于2.14%。  相似文献   
388.
Aliphatic liquid as a basic fuel was incinerated in a laboratory scale pilot plant. Inorganic chlorine and organic chlorine mixed with basic fuel were used as additive chemicals. Sodium chloride (NaCl) and tetrachloroethylene (C2Cl4) were used as the sources of inorganic and organic chlorine. Combustion parameters were adjusted for optimum combustion and, consequently, the amount of particles in flue gases was low. The concentrations of chlorine in flue gases were high enough for possible formation reactions of organic chlorinated compounds in all of the chlorine input tests. An increase in chlorine input did not significantly increase the amounts of highly chlorinated organic compounds, like PCDD/Fs. The main result was that chlorophenol concentrations increased in parallel with organic chlorine input. Comparing organic chlorine to inorganic chlorine tests showed that more highly substituted PCDD/F congeners were formed when organic chlorine was the additive chlorine source. The formation of highly chlorinated organic compounds such as PCDD/Fs requires not only chlorine and aliphatic fuel to be formed, but some catalysts are also needed.  相似文献   
389.
Measuring the amount of fossil fuel carbon stored in the vegetation is now crucial to understand the mechanisms ruling climate changes. In this respect, highly polluted areas such as major towns represent “natural” laboratories because fossil fuel CO2 (14C-free) is isotopically distinct from mean atmospheric CO2 (14C-labeled). Here, a14C study of urban grasses near a major highway in Paris, France, shows that plants store up to 13% of fossil fuel carbon. The 14C composition of urban grasses is thus a novel parameter to assess the fossil fuel CO2 pollution.  相似文献   
390.
Liquefied natural gas (LNG) is widely used to cost-effectively store and transport natural gas. However, a spill of LNG can create a vapor cloud, which can potentially cause fire and explosion. High expansion (HEX) foam is recommended by the NFPA 11 to mitigate the vapor hazard and control LNG pool fire. In this study, the parameters that affect HEX foam performance were examined using lab-scale testing of foam temperature profile and computational fluid dynamics (CFD) modeling of heat transfer in vapor channels. A heat transfer model using ANSYS Fluent® was developed to estimate the minimum HEX foam height that allows the vapors from LNG spillage to disperse rapidly. We also performed a sensitivity analysis on the effect of the vaporization rate, the diameter of the vapor channel, and the heat transfer coefficient on the required minimum height of the HEX foam. It can be observed that at least 1.2 m of HEX foam in height are needed to achieve risk mitigation in a typical situation. The simulation results can be used not only for understanding the heat transfer mechanisms when applying HEX foam but also for suggesting to the LNG facility operator how much HEX foam they need for effective risk mitigation under different conditions.  相似文献   
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