粉煤流化床（PCF—FBC）燃烧特性的试验研究

本文首次提出一种新型的高效、清洁煤燃烧方法，即粉煤流化床（ＰＣＦ－ＦＢＣ）燃烧技术，并在０．３ＭＷ的试验台上系统研究了其燃烧特性。该项技术全部燃用煤粉，且同时具有煤粉炉和流化床锅炉的特点。研究结果表明：煤粉能在ＰＣＦ－ＦＢＣ中温度为８５０￣８８０℃的流化床区（ＦＢＣＺ）稳定着火，释放出５７．７％￣８４．２％的挥发份，并完成部分炭及部分挥发份的燃烧（约７０％左右）；ＰＣＦ－ＦＢＣ的炉内最高烟温为１１     

运行参数对粉煤流化床（ＰＣ—ＦＢ）燃烧效率的影响

在一座０．３ＭＷ热输入的ＰＣ－ＦＢＣ试验台上进行了试验研究,获得了不同操作ＰＣ－ＦＢ燃烧效率的试验数据,详细讨论了这些参数对ＰＣ－ＦＢ燃烧效率的影响规律。研究结果表明,粉煤流化床的燃烧效率最高达９８％－９９％,可与煤粉炉相媲美。本试验研究亦首次,提出,只要燃烧温度、颗粒停留时间、火焰湍流度（３Ｔ）及炉内氧浓度、颗粒浓度（２Ｃ）合理匹配,就能够实现煤粉的低温度高效燃烧。     

粉煤流化床燃烧中N2O的生成特性

粉煤流化床（ＰＣ－ＦＢ）是一项燃烧效率高,同时实现炉内脱硫,低ＮＯｘ和Ｎ２Ｏ排放的新型高效、清洁煤燃烧技术,在一座０．３ＭＷ的试验台上,研究了其Ｎ２Ｏ生成与分布特性,包括床层温度Ｔｂ、流化速度Ｕｏ、二次风率Ｒ２,ＰＣ－ＦＢ流化床燃烧区（ＦＢＣＺ）出口氧浓度Ｏ２、钙硫化（Ｃａ／Ｓ）对ＦＢＣＺ出口Ｎ２Ｏ浓度的影响;以及各层二次风份额（Ｒ２ｉ％）及悬浮空间燃烧区（ＦＣＺ）的温度分布与炉内Ｎ２Ｏ浓度分布的     

粉煤流化床(PC-FB)燃烧的NO生成与排放控制特征

粉煤流化床（ＰＣ－ＦＢ）是一项燃烧效率高,同时实现炉内脱硫、低ＮＯｘ和Ｎ２Ｏ排放的新型高效、清洁煤燃烧技术。在１座０．３ＭＷ的试验台上研究了其ＮＯ生成与排放控制特性。主要研究内容包括：各层二次风份额（Ｒ２ｉ％）及悬浮空间燃烧区（ＦＣＺ）的温度分布与炉内ＮＯ浓度分布的关系;床层温度Ｔｂ、流化速度Ｕｏ、二次风率Ｒ２、ＰＣ－ＦＢ流化床燃烧区（ＦＢＣＺ）出口氧浓度Ｏ’２、钙硫化（Ｃａ／ｓ）等对ＰＢＣＺ出口ＮＯ浓度ＮＯ’、ＰＣＦＢ炉膛出口ＮＯ浓度ＮＯ”的影响。图１２参１０     

运行参数对粉煤流化床_PC_FB_密相燃烧区燃烧特性的影响

在一座0．3MW热输入的煤粉流化床燃烧（PC－FBC）试验台上,研究了煤粉在其密相燃烧区内的燃烧特性,文中用密相燃烧区内煤粉挥发份的释放率V^τ（％）,及其出口处煤灰的碳含量C（％）,来描述此特性,并研究了床温、氧浓度、流化速度、二次风率时V^τ（％）,C（％）的影响规律。研究表明,煤粉在密相燃烧区内释放57．4％－84％的挥发分和燃烧20％－30％左右的固定碳,释放40％－50％的发热量。     

高强度耐热不锈钢板的开发

高强度耐热不锈钢板的开发据“火力原子发电”１９９７年２月号报道，日本钢管综合材料技术研究所（ＮＫＫ公司）已开发了用于增压流化床燃烧（ＰＦＢＣ）联合循环电站高温应用的钢板－２２％Ｃｒ－１５Ｎｉ－０．７Ｎｂ－０．１５Ｎ。８００℃～９００℃下，开发钢板的耐...     

粉煤流化床燃烧_PC_FBC_炉膛烟温试验研究

针对新型高效、清洁煤燃烧方式,即粉煤流化床（ＰＣ－ＦＢ）,在一座０．３ＭＷ的试验台上,系统而详细地研究了ＰＣ－ＦＢ炉膛空间烟气温度的分布特性。主要研究内容包括：ＰＣ－ＦＢ炉膛空间内烟流的稳定性与均匀性;床层温度、流化速度、床料的平均粒径、二次风率、二次风的投入位置对炉膛内烟温分布的影响,并总结出合理的炉膛烟温分布。     

整体煤气化联合循环发电技术进展

通过对５大典型技术（ＭＧＣＣ天然气联合循环、ＰＣ＋ＦＧＤ煤粉炉＋烟气处理装置、ＡＦＢＣ常压循环流化床、ＰＦＢＣ增压循环流化床和ＩＧＣＣ整体煤气化联合循环）的经济性和环保性能比较，认为ＩＧＣＣ发电技术由于其效率高、对煤种适应性广，且利用脱硫和氧气氧化，环保指标好、副产品可再利用不会造成二次污染等特点，是２１世纪最有发展前任的一种清洁发电技术。     

ACFB与PCFB灰特性的比较研究

流休床燃烧技术的出现为解决因各种化石燃料的利用而带来的环境问题提供了很好的途径。在不久的将来，增压循环流化床（ＰＣＦＢ）燃烧技术将具有广阔的市场前景。这里须弄清ＰＣＦＢ燃烧产物中灰的特性与常压循环流化床（ＡＣＦＢ）燃烧产物中灰的特性的异同。不过，燃烧产物中灰的各组成成份将随加入的脱硫剂量和机组运行工况的不同而有很大的变化。在燃料中硫含量一定和同种脱硫剂的情况下，ＰＣＦＢ锅炉燃烧产生的灰量通常较ＡＣＦＢ锅炉燃烧产生的灰量要少，这主要是由于在增压锅炉中仅需较少的脱硫剂。上述两种锅炉中因脱硫产生的灰量之所以有差异，同时又是由于在常压和增压条件下脱硫反应机理的不同。本文所用到的灰样来自于商用ＡＣＦＢ电站和ＦＷ公司在芬兰卡弗莱的１０ＭＷ ＰＣＦＢ中试电站。文中叙述的灰特性和文中提供的ＡＣＦＢ灰样或ＰＣＦＢ灰样较其它地方所     

我国现有的火电机组改造成为PFBC—CC的全工况性能分析

通过对我国现有火电机组情况的分析，指出将５０－１２５ＭＷ火电机组改造成为ＰＦＢＣ－ＣＣ（增压流化床燃烧联合循环）是较合适的。以１００ＭＷ火电机组为例进行计算，在改造成为ＰＦＢＣ－ＣＣ后的供电效率可提高５个百分点，接着计算其变工况性能并进行分析，着重指出为适应ＰＦＢＣ炉的工作要求，对燃气轮机空气流量进行调节的必要性。     

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.