Reactivity of steam in exhaust gas catalysis III. Steam and oxygen/steam conversions of propane on a Pd/Al2O3 catalyst

A 1% Pd catalyst (38% dispersion) was prepared by impregnating a γ-alumina with palladium acetylacetonate dissolved in acetone. The behaviour of this catalyst in oxidation and steam reforming (SR) of propane was investigated. Temperature-programmed reactions of C₃H₈ with O₂ or with O₂ + H₂O were carried out with different stoichiometric ratios S(S =[O₂]/5[C₃H₈]). The conversion profiles of C₃H₈ for the reaction carried out in substoichiometry of O₂ (S < 1) showed two discrete domains of conversion: oxidation at temperatures below 350°C and SR at temperatures above 350°C. The presence of steam in the inlet gases is not necessary for SR to occur: there is sufficient water produced in the oxidation to form H₂ and carbon oxides by this reaction. Contrary to what was observed with Pt, an apparent deactivation between 310 and 385°C could be observed with Pd in oxidation. This is due to a reduction of PdO_x into Pd⁰, which is much less active than the oxide in propane oxidation. Steam added to the reactants inhibits oxidation while it prevents the reduction of PdO_x into Pd⁰. Compared to Pt and to Rh, Pd has a higher thermal resistance: no deactivation occurred after treatment up to 700°C and limited deactivation after treatment up to 900°C, provided that the catalyst is maintained in an oxygen-rich atmosphere during the cooling.     

Fuzzy logic for signal prediction in nuclear systems

In this paper, we present a fuzzy logic-based algorithm which allows to build a predictive model of an evolving signal. The if-then rules are inferred from the available input-output data. The errors of the model predictions with respect to the measured plant signals can then be used to detect, in real-time, any deviation of the process due either to a component's failure or to an operator's action. Applications of the approach are presented with respect to a chaotic time series of literature and to the water level in the steam generator of a PWR.     

火电厂锅炉火用损失大不等于节能潜力大

本文通过对电厂锅炉火用损失的进一步分析计算，认为现有锅炉火用损失之大部分是不可避免的，“锅炉火用效率可以大幅度提高”的观点是不切实际的。文章对火电厂节能工作具有一定的指导作用。     

Optimization of abrasive water jet cutting of ductile materials

Full factorial design of experiments was developed in order to investigate the effects of jet pressure, abrasive mixing rate, cutting feed, and plate thickness upon three response variables, surface finish of cutting wear zone, percentage proportion of striation free area, and maximum width of cut. The set of sixteen experiments was performed on each of the following two ductile materials: AISI 4340 (high strength low alloy steel, hardened to 49HRc) and Aluminum 2219. Analysis of Variance (ANOVA) was performed on experimental data in order to determine the significance of effects of different parameters on the performance measures. It was found that cutting feed and thickness were highly influential parameters, while abrasive mixing rate is influential upon surface roughness only. Strong interaction was found between jet pressure and workpiece material. Multi-criteria numerical optimization was performed in order to simultaneously maximize/minimize different combinations of performance measures.     

燃气蒸汽联合循环电站及其在山西发展的前景

论述了燃气蒸汽联合循环电站的发展和优点 ,认为这是山西电力发展的方向和老厂改造的途径     

机组初参数的热经济性模型研究及其应用

以汽轮机功率方程为基础,应用偏微分理论,根据汽轮机变工况的基本原理以及各参数之间的变化关系,经过严格的数学推导,得到了主蒸汽参数变化对机组热经济性影响的数学计算模型。此外,还以N600-16.7/537/537-I型汽轮机的运行数据为例,对模型进行验证。计算实例表明:该模型具有计算结果准确、使用方便、通用性强等特点,适用于工程实际应用,对机组性能监测和优化运行有重要意义。     

XQG型石墨二合一氯化氢蒸汽炉及其应用效益

本文对XQG型石墨二合一氯化氢蒸汽炉的结构、性能进行了介绍,并分析了其应用效益。     

合成射流激励影响扩散燃烧NOx生成的实验研究

对合成射流激励助燃风影响NOx生成进行了实验研究,主要考察了合成射流频率、幅值对燃烧器内掺混区时均速度、NOx含量、温度等参数分布的影响。实验结果表明,加入适当频率的合成射流激励助燃风,能够增强径向、周向速度幅值,改善天然气与助燃风的掺混,降低“热点”温度和NOx生成量（较无激励时最多降低约14％）,这有益于降低天然气燃烧造成的大气污染。     

SINOPEC’s Successin Fixed-bed Methanol-to-Propylene PilotScale Tests

正The first in China pilot tests of fixed-bed methanol-topropylene unit were successfully implemented at the Yangzi Petrochemical Company(YPC).It is told that this technology has opened up a new process for production of propylene through coal gasification,and China has possessed both the fluidized-bed methanolto-propylene process(F-MTP)and the stationary-bed     

300 MW机组变压运行方式的研究

针对300 MW机组运行经济性问题,通过试验测定了不同负荷下定压运行或变压运行时的供电煤耗、热耗、汽耗、汽动给水泵单耗、再热汽温等指标,并进行了对比和分析。结果显示,机组负荷在240 MW以下时采用四阀全开变压运行比较经济。