火力发电厂6kV输煤皮带电机轴承烧损探讨

火力发电厂常遇到电机轴承烧损的问题,常见的6kV的高压输煤电机轴承损坏,会影响到机组的安全运行,让火力发电厂蒙受较大损失。文章主要对一个2×600MW超临界机组电厂6 kV输煤皮带电机轴承烧损问题进行分析,并提出了处理及预防方案,可供同类电厂借鉴。     

电厂输煤系统堵煤浅析及处理

火力发电厂输煤系统堵煤是较为严重的问题。文章对电厂输煤系统堵煤问题进行分析研究，并在此基础上以野马寨发电有限公司为例，论述如何应对这一问题。     

浅谈锅炉输煤系统粉尘超标的治理

本文针对梅县电厂2×1 35MW循环流化床锅炉机组输煤系统运行时粉尘大的问题,分析了粉尘超标的危害及原因,并有针对性地进行改进治理,得到较好效果,对存在同类问题的电厂输煤系统的改造有一定的借鉴.     

对于火力发电厂燃料系统安全运行的探究分析

输煤系统是火力发电厂里重要的标志性组成部分,而输煤皮带的安全运行最为直接的影响了电厂的安全指标和经济效益。本文从火力发电厂燃料运行系统安全运行方面,对其影响因素进行分析探究,并提出防范对策,让今后在有效维护和保证系统安全运行时有所参考。     

厂用电互联模式下备用/检修电源快速切换探讨

为减少下网电量，降低生产成本，越来越多的火力发电厂采用6 kV厂用电互联方式，即一台机组运行，另一台相邻机组检修时，由运行机组向检修机组提供检修电源。但常规厂用电快切装置只实现6kV工作电源与备用电源之间的快速切换。备用电源与检修电源之间采用手动切换，需倒换380V负荷，操作步骤多。本文以湖南省某火力发电厂为例，探讨通过厂用电快切装置及BZT装置实现备用电源与停机检修电源快速切换的可行性。     

阳西电厂输煤程控系统应用及火电厂输煤系统监控方式探讨

文章介绍了广东华厦阳西电厂一期工程首2台机组工程(2×600 MW)输煤程控系统,并结合该工程对火电厂输煤系统监控方式进行简单探讨。     

火力发电厂输煤系统输送机皮带跑偏综合治理

火力发电厂配套输煤系统大多采用皮带输送机进行上煤供应燃料,在输煤系统试运和运行过程中,输煤栈桥、卸煤沟、存煤场、煤仓间等处漏撒煤料普遍存在,其中,皮带输送机皮带跑偏是主要肇事者。本文结合多年来多个电厂输煤系统安装、试运、消缺实践,从皮带输送机结构原理、跑偏原因、纠偏和预防措施三个方面论述皮带跑偏综合治理措施。     

阳西电厂输煤程控系统应用及火电厂输煤系统监控方式探讨

文章介绍了广东华厦阳西电厂一期工程首2台机组工程（2×600 MW）输煤程控系统,并结合该工程对火电厂输煤系统监控方式进行简单探讨。     

广西来宾电厂2×125 MW机组烟气脱硫改造工程环境影响分析

文章通过对广西来宾电厂2×125 MW机组烟气脱硫改造工程建设条件及脱硫工艺方案的选择进行分析,论述电厂烟气脱硫改造前后主要污染物排放情况及环境影响情况,提出切实可行的污染防治对策,为火力发电厂老机组进行二氧化硫减排提供科学依据.     

电袋除尘器改造及运行效果分析

根据国家现行《火力发电厂大气污染物排放标准》(GB13223-2003),并综合考虑国家《火力发电厂污染物排放标准》(征求意见稿23-2000)的要求.牡二电厂#6机组现采用静电除尘器,其除尘效率在98.04％.严重低于国家标准.通过反复多方论证后对原#6炉的静电除尘器进行了静电与布袋复合除尘改造,取得了成功.其改造费用低、除尘效率、排放率均达到国家标准.     

Some Virtues of Speculation

Why are stock markets and foreign exchange markets so volatile? Professor Wolfgang Kasper, of the University of New South Wales, explains the difference between flow and asset markets and argues that changes in expectations cause the volatility of the latter.     

Some approximations of n-copulas

We consider several approximations to n-copulas: the checkmin, checkerboard, Bernstein, and shuffle of min approximations. The checkerboard, Bernstein, and shuffle of min approximations have been studied in the n = 2 case. We investigate these constructions in arbitrary finite dimensions and consider some of the ways in which they converge or fail to converge to the original copula.     

Some approximate equilibria

It is by now well-known that there exists a system of prices at which decentralized, utility-maximizing behavior by a finite number of agents, each with convex preferences, leads to outcomes which ‘mesh’ in the aggregate. Technically, a competitive equilibrium is said to exist. The question arises as to what happens with non-convex preferences. Using Non-standard Analysis, we show that, provided the economy is ‘large’ enough, there exist various formulations of approximate competitive equilibria. We also relate our results to other work in this area.     

Some Informational Aspects of Conservatism

Abstract

When two value estimates are about equally likely, conservatism dictates reporting the less optimistic one (e.g. Lower of Cost or Market). We use an analytical model to investigate informational implications of this dictum, and identify types of environments where the conservative accounting treatment is more informative than a predetermined choice. The bias induced by the conservative choice is found to be adequately moderate, never excessive. It benefits users of the financial statements that take the reported figures at face value whenever upside errors are more costly (possibly only slightly more costly) than similar downside errors. Sophisticated users, who know how to give the reports the best possible interpretation, benefit from the lower variability, not from the bias. These latter benefits are least ambiguous when upside errors and downside errors are about equally costly.     

Some properties of Rho-b statistics

This article asseses the utility of Spearman's rho-b in path analyses. First, the performance of rho-based statistics are tested against Kim's criteria. The method works quite well on monotonic data, and under certain circumstances perfect detection of underlying interval structures is possible. Second, problems of implementing multivariate analyses with Spearman statistics are discussed. The simplest procedure is to recode the variables as ranks and to use Pearson algorithms and tests of significance. These are valid.     

Some problems of data standardization

Procedure of aggregation of component indicators into one composite index of a multi-dimensional phenomenon under study requires previous standardization of the original raw data in terms of which the component indicators are expressed. The standardization is inevitably connected with an arbitrary choice of a mathematical formula by which the same measurement units, for all component indicators, are established. It is argued that by choosing one of the several possible standardization formulae, a researcher, most often unkowingly, ascribes differential weights to particular component indicators. Two approaches, in solving the problem of arbitrariness of the choice of the standardization formula, are possible: (1) assessment of the margin of “error of arbitrariness,” or “standardization effect,” and the interpretation of substantive results obtained after the aggregation, within that margin; (2) evaluation of equivalencies of things, established by the alternative standardization formulae, in order to choose the formulae ensuring the most acceptable equivalence as judged by certain objective norms or criteria. The two approaches are discussed, and numerical examples illustrating each of them are presented using two kinds of standardization: the one based on percentages, and the other on the deviation from the mean divided by standard deviation.