发电企业开发CDM项目的意义和潜力分析

《京都议定书》生效以后,CDM市场非常活跃。我国拥有非常大的CDM供给潜力,但由于CDM在我国开展时间不长,很多企业对CDM还不十分了解。本文分析了发电企业参与CDM活动的意义,并根据CDM开发规则对可成为CDM的项目潜力进行了分析,并提出有关开发建议。     

我国农业及畜牧业发展CDM项目的潜力分析

文章阐述了清洁发展机制CDM的内涵以及农业、畜牧业对温室气体的贡献,分析了农业、畜牧业发展CDM项目的巨大潜力,提出了农业、畜牧业通过发展CDM项目将大幅减弱全球温室效应,又可促进我国的可持续发展.     

我国生物质固体成型燃料CDM项目开发前景分析

生物质能领域是我国开展CDM项目的重点领域之一,而生物质固体成型燃料技术又是生物质能主要利用技术之一,但目前我国尚未有在EB成功注册的生物质固体成型燃料CDM项目。文章以农业部示范项目为例,分析了我国生物质固体成型燃料产业发展现状、开发CDM项目的可行性、适用方法学及开发潜力,认为在我国开发生物质固体成型燃料CDM项目是可行的并具有较好的开发前景,建议开发专门的小规模方法学用于指导该领域CDM项目的开发,促进其产业化发展。     

城市生活垃圾焚烧发电CDM项目案例分析

本文分析评价了我国城市生活垃圾的产生量、资源量、国内外垃圾焚烧技术应用状况、制约我国城市生活垃圾焚烧技术应用的主要因素以及垃圾焚烧发电技术应用潜力。本研究以城市生活垃圾焚烧发电技术为案例,基于三个基准线,应用增量成本分析方法,计算了垃圾焚烧发电作为CDM(清洁发展机制)项目的单位碳减排成本并对其进行了敏感性分析,提出城市生活垃圾焚烧发电技术应作为我国与发达国家进行CDM项目合作的优先技术领域。     

我国风电CDM项目发展现状及潜力分析

风电项目是清洁发展机制(CDM)项目开发的重点,在CDM市场中占有很大的比例.文章阐述了清洁发展机制的概念,介绍了我国风电CDM项目开发的现状,提出了促进风电CDM项目开发的建议.目前,我国官方受理的风电CDM项目的CO2减排量(CERs)已达到657万t/a.按照国家规划目标,预测到2012年风电CDM项目的CERs潜力可达到3 600～5 000万t.     

清洁发展机制(CDM)及项目实施介绍

CDM是一个新的国际合作机制,如何了解和充分有效的利用好这一机制,使之服务于本国的经济发展是许多国家普遍面临的问题。我国已经建立CDM的管理机构,颁布了"清洁发展机制项目运行管理暂行办法"。在全方位多层次开展能力建设的同时,积极推进CDM项目的实施,到2004年年底已经批准了两个CDM项目。中国被视为最具潜力的CDM市场。要将这一潜在的市场变为现实还有大量的工作要做,如进一步完善CDM项目的管理办法、审批程序和相关的政策,建立我国自己的项目咨询机构以减少交易成本,提高企业参与的积极性等。CDM已经被越来越多的人所了解和认识,相信我国一定能够很好地利用这一机制,在为人类应对气候变化的挑战做出贡献的同时,最大限度地服务于我国国民经济与环境的可持续协调发展。     

考虑二氧化硫排放的清洁发展机制协同效应分析

为了解清洁发展机制（CDM）项目在电力行业的协同效应,建立了二氧化硫排放量的参数估计方程,引入profile-kernel估计方法估计参数,并以中国实际CDM项目为例,评估了CDM项目的二氧化硫排放的协同效应,进一步识别和判断了CDM项目的额外性。研究发现,碳排放信用额的参数估计为负值,可见CDM项目确实能减少二氧化硫排放,但参数估计值较小,表明CDM项目在减少二氧化硫排放方面的效应并不十分显著,这也对其额外性带来了一定的挑战,意味着即使无CDM项目资金的支持,项目仍会发生。     

关于建立我国清洁发展机制(CDM)项目运行管理机制的几点建议(一)

我国是温室气体减排潜力较大的发展中国家之一,开展CDM(清洁发展机制)合作的市场前景广阔,为主要的发达国家所看好。在这种形势下,除了进一步开展对CDM的方法学、体制、影响及对策的研究,加强能力建设外,做好市场和技术准备,把握住CDM的国际合作机会,促进我国的可持续发展则更为重要。因此,本文在研究全球层面上CDM的运作程序和CDM项目管理与执行机构建设的基础上,提出了建立我国CDM项目运行管理机制的基本原则,并为建立CDM项目运行管理机制的基本架构,确定不同层面CDM运行管理机构的相互关系,CDM项目运行管理机构的职能和不同层面CDM管理机构的运作机制等提出了具体建议。     

我国农村沼气CDM项目开发的潜力分析

清洁发展机制能为我国的可持续发展带来新的契机。本文对农村大中型沼气工程和户用沼气池的减排温室气体的潜力作了定量的分析,认为农村沼气工程适合开发成CDM项目。CDM能给农村沼气工程带来发展的机遇,提供更宽的融资渠道和技术支持。最后对当前农村沼气CDM项目开发中存在的一些障碍进行了分析。     

我国户用生物质炉灶的发展和应用

回顾了我国户用生物质炉灶的发展历程,介绍了我国生物质炉灶的推广应用现状和技术水平,分析了生物质炉灶性能测试标准和评价方法;阐述了应用生物质炉灶技术开发CDM项目的发展现状、开发方法以及未来发展的巨大潜力;最后提出了生物质炉灶技术应用发展的建议。     

Ash-forming elements in four Scandinavian wood species. Part 1: Summer harvest

Woody biomass in Finland and Sweden comprises mainly four wood species: spruce, pine, birch and aspen. To study the ash, which may cause problems for the combustion device, one tree of each species were cut down and prepared for comparisons with fuel samples. Well-defined samples of wood, bark and foliage were analyzed on 11 ash-forming elements: Si, Al, Fe, Ca, Mg, Mn, Na, K, P, S and Cl. The ash content in the wood tissues (0.2–0.7%) was low compared to the ash content in the bark tissues (1.9–6.4%) and the foliage (2.4–7.7%). The woods’ content of ash-forming elements was consequently low; the highest contents were of Ca (410–1340 ppm) and K (200–1310), followed by Mg (70–290), Mn (15–240) and P (0–350). Present in the wood was also Si (50–190), S (50–200) and Cl (30–110). The bark tissues showed much higher element contents; Ca (4800–19,100 ppm) and K (1600–6400) were the dominating elements, followed by Mg (210–2400), P (210–1200), Mn (110–1100) and S (310–750), but the Cl contents (40–330) were only moderately higher in the bark than in the wood. The young foliage (shoots and deciduous leaves) had the highest K (7100–25,000 ppm), P (1600–5300) and S (1100–2600) contents of all tissues, while the shoots of spruce had the highest Cl contents (820–1360) and its needles the highest Si content (5000–11,300). This paper presented a new approach in fuel characterization: the method excludes the presence of impurities, and focus on different categories of plant tissues. This made it possible to discuss the contents of ash element in a wide spectrum of fuel-types, which are of large importance for the energy production in Finland and Sweden.     

NEXT GENERATION ENGINEERED MATERIALS FOR ULTRA SUPERCRITICAL STEAM TURBINES

正1 ABSTRACT To reduce the effect of global warming on our climate,the levels of CO2emissions should be reduced.One way to do this is to increase the efficiency of electricity production from fossil fuels.This will in turn reduce the amount of CO2emissions for a given power output.Using US practice for efficiency calculations,then a move from a typical US plant running at 37%efficiency to a 760℃/38.5 MPa(1 400/5 580 psi)plant running at 48%efficiency would reduce CO2emissions by 170kg/MW.hr or 25%.     

Contents in Volume 23,2014

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Aerodynamic performance effects of leading-edge geometry in gas-turbine blades

The purpose of this paper is to illustrate the advantages of the direct surface-curvature distribution blade-design method, originally proposed by Korakianitis, for the leading-edge design of turbine blades, and by extension for other types of airfoil shapes. The leading edge shape is critical in the blade design process, and it is quite difficult to completely control with inverse, semi-inverse or other direct-design methods. The blade-design method is briefly reviewed, and then the effort is concentrated on smoothly blending the leading edge shape (circle or ellipse, etc.) with the main part of the blade surface, in a manner that avoids leading-edge flow-disturbance and flow-separation regions. Specifically in the leading edge region we return to the second-order (parabolic) construction line coupled with a revised smoothing equation between the leading-edge shape and the main part of the blade. The Hodson–Dominy blade has been used as an example to show the ability of this blade-design method to remove leading-edge separation bubbles in gas turbine blades and other airfoil shapes that have very sharp changes in curvature near the leading edge. An additional gas turbine blade example has been used to illustrate the ability of this method to design leading edge shapes that avoid leading-edge separation bubbles at off-design conditions. This gas turbine blade example has inlet flow angle 0°, outlet flow angle −64.3°, and tangential lift coefficient 1.045, in a region of parameters where the leading edge shape is critical for the overall blade performance. Computed results at incidences of −10°,   −5°,   +5°,   +10° are used to illustrate the complete removal of leading edge flow-disturbance regions, thus minimizing the possibility of leading-edge separation bubbles, while concurrently minimizing the stagnation pressure drop from inlet to outlet. These results using two difficult example cases of leading edge geometries illustrate the superiority and utility of this blade-design method when compared with other direct or inverse blade-design methods.     

Hydrogen production by steam-gasification of carbonaceous materials using concentrated solar energy – V. Reactor modeling,optimization, and scale-up

A chemical reactor for the steam-gasification of carbonaceous particles (e.g. coal, coke) is considered for using concentrated solar radiation as the energy source of high-temperature process heat. A two-phase reactor model that couples radiative, convective, and conductive heat transfer to the chemical kinetics is applied to optimize the reactor geometrical configuration and operational parameters (feedstock's initial particle size, feeding rates, and solar power input) for maximum reaction extent and solar-to-chemical energy conversion efficiency of a 5 kW prototype reactor and its scale-up to 300 kW. For the 300 kW reactor, complete reaction extent is predicted for an initial feedstock particle size up to 35 μm at residence times of less than 10 s and peak temperatures of 1818 K, yielding high-quality syngas with a calorific content that has been solar-upgraded by 19% over that of the petcoke gasified.     

汽轮机数字电液调节系统挂闸异常的技术完善

分析了200MW汽轮机数字电液调节系统在运行中存在的挂闸异常问题,采取了相应的技术处理措施,且运行实践效果良好。     

新型高压共轨ECU升压模块的数字化开发与优化

为了提高喷油器电磁阀的响应速率,提出了一种基于CPLD(复杂可编程逻辑器件)应用于高压共轨ECU的数字升压模块。鉴于该升压电路结构参数多,其升压电压的恢复响应要求高等特征,基于Pspice建立了升压电路的仿真模型,研究了不同电路参数下升压模块的输出特性,全面优化了该升压模块的性能。结果显示,该升压模块的最大转换效率可以达90%以上。在柴油发动机上对ECU的试验表明,升压电压最大波动不超过10%,其恢复时间仅为1.3ms,功率管最大温升仅为41℃,满足整机运行范围内ECU的需求。     

Trace metal chemistry and silicification of microorganisms in geothermal sinter, Taupo Volcanic Zone, New Zealand

As part of a pilot study investigating the role of microorganisms in the immobilisation of As, Sb, B, Tl and Hg, the inorganic geochemistry of seven different active sinter deposits and their contact fluids were characterised. A comprehensive series of sequential extractions for a suite of trace elements was carried out on siliceous sinter and a mixed silica-carbonate sinter. The extractions showed whether metals were loosely exchangeable or bound to carbonate, oxide, organic or crystalline fractions. Hyperthermophilic microbial communities associated with sinters deposited from high temperature (92–94°C) fluids at a variety of geothermal sources were investigated using SEM. The rapidity and style of silicification of the hyperthermophiles can be correlated with the dissolved silica content of the fluid. Although high concentrations of Hg and Tl were found associated with the organic fraction of the sinters, there was no evidence to suggest that any of the heavy metals were associated preferentially with the hyperthermophiles at the high temperature (92–94°C) ends of the terrestrial thermal spring ecosystems studied.     

Assessment methods of material ageing using Sdobyrev''s creep rupture model

The physical aspects of the activation energy, in higher and high temperatures, of the metal creep process were examined. The research results of creep-rupture in a uniaxial stress state and the criterion of creep-rupture in biaxial stress states, at two temperatures, are then presented. For these studies creep-rupture, taking case iron as an example the energy and pseudoenergy activation was determined. For complex stress states the criterion of creep-rupture was taken to be Sdobyrev's, i.e. σ_red = σ₁ β + (1 − β)σ_i, where: σ₁-maximal principal stress, σ_i-stress intensity, β-material constant (at variable temperature β = β(T)). The methods of assessment of the material ageing grade are given in percentages of ageing of new material in the following mechanical properties: 1) creep strength in uniaxial stress state, 2) activation energy in uniaxial stress state, 3) criterion creep strength in complex stress states, 4) activation pseudoenergy in complex stress states. The methods 1) and 3) are the relatively simplest because they result from experimental investigations only at nominal temperature of the structure work, however, for methods 2) and 4) it is necessary to perform the experimental investigations at least at two temperatures.     

Production of hydrogen from sewage biosolids in a continuously fed bioreactor: Effect of hydraulic retention time and sparging

Hydrogen was produced from primary sewage biosolids via mesophilic anaerobic fermentation in a continuously fed bioreactor. Prior to fermentation the sewage biosolids were heated to 70 °C for 1 h to inactivate methanogens and during fermentation a cellulose degrading enzyme was added to improve substrate availability. Hydraulic retention times (HRT) of 18, 24, 36 and 48 h were evaluated for the duration of hydrogen production. Without sparging a hydraulic retention time of 24 h resulted in the longest period of hydrogen production (3 days), during which a hydrogen yield of 21.9 L H₂ kg⁻¹ VS added to the bioreactor was achieved. Methods of preventing the decline of hydrogen production during continuous fermentation were evaluated. Of the techniques evaluated using nitrogen gas to sparge the bioreactor contents proved to be more effective than flushing just the headspace of the bioreactor. Sparging at 0.06 L L min⁻¹ successfully prevented a decline in hydrogen production and resulted in a yield of 27.0  L H₂ kg⁻¹ VS added, over a period of greater than 12 days or 12 HRT. The use of sparging also delayed the build up of acetic acid in the bioreactor, suggesting that it serves to inhibit homoacetogenesis and thus maintain hydrogen production.