GE MOST紧急停车系统在300kt/a尿素装置的应用

介绍GE MOST紧急停车系统在柳州化工股份有限公司300 kt/a尿素装置上的应用情况,详细阐述了GE MOST系统的硬件配置、软件功能和主要控制回路逻辑。     

基于GE Fanuc的MPS模块化生产制造系统设计

MPS系统是一种高生产率和可重构的生产制造系统,是时代发展的潮流。利用MPS系统的特点,选用GE Fanuc控制器对其进行进一步的改造。首先分析介绍MPS系统的结构设计及系统组成,并给出系统组成图;然后阐述所构成的各个工作单元的控制功能,并给出相应的程序流程图;最后以加工单元为例,根据给出的I/O分配表编写梯形图程序。运行结果表明,基于GE Fanuc的MPS系统具有较好的可行性,有很大的实际应用意义。     

Nonuniform Encoding and Hybrid Decoding Schemes for Equal Error Protection of Rateless Codes

Messages are generally selected with the same probability in the encoding scheme of rateless codes for equal error protection. In addition, a belief propagation (BP) decoding scheme is generally used because of the low computational complexity. However, the probability of recovering a new message by BP decoding is reduced if both the recovered and unrecovered messages are selected uniformly. Thus, more codeword symbols than expected are required for the perfect recovery of message symbols. Therefore, a new encoding scheme with a nonuniform selection of messages is proposed in this paper. In addition, a BP‐Gaussian elimination hybrid decoding scheme that complements the drawback of the BP decoding scheme is proposed. The performances of the proposed schemes are analyzed and compared with those of the conventional schemes.     

EX2100励磁调节器ECTB板损坏导致机组全停的分析

对由于美国GE EX2100励磁调节器ECTB板硬件损坏导致机组全停事故案例进行了详细的分析,在现场故障记录不全、不准确,故障信息烦琐的情况下,通过准确的分析方法和事故判断,查明事故原因所在。     

60万t/a甲醇项目GE水煤浆气化装置运行总结

兖州煤业榆林能化有限公司60万t/a甲醇项目气化装置采用GE水煤浆气化技术,气化炉2开1备。分析了装置运行过程中存在的问题及其原因;总结了相关整改措施及其效果。     

Non‐varnishing and tribological characteristics of polyalkylene glycol‐based synthetic turbine fluid

Varnish build‐up in heavy duty gas turbines is a leading cause of costly unplanned shutdowns and resulting lost power generation capacity. The culprit is the conventional petroleum‐based turbine oil, which breaks down to form varnish and sludge that cause servo valves to stick. Use of filtration to remove solid degradation by‐products addresses a symptom but not the root cause of varnish formation: the petroleum‐based turbine oils themselves. For the best protection against varnish‐related shutdowns, a switch from petroleum‐based turbine oil to non‐varnishing polyalkylene glycol (PAG)‐based synthetic turbine fluid was undertaken by four power plants in North America. PAG‐based synthetic turbine fluid chemistry, its tribological characteristics and successful trials in GE 7FA heavy duty gas turbines (General Electric Company, Fairfield, CT, USA) are discussed in this paper. PAG‐based synthetic turbine fluid has outperformed the hydrocarbon turbine oil in reduced sludge and varnish formation due to its polar nature and solvating power in plant trials as well as in a modified ASTM D 2893 test. Copyright © 2011 John Wiley & Sons, Ltd.     

无烟煤在GE水煤浆气化装置的成功应用

对世界上首套以无烟煤为原料的金赤化工GE水煤浆气化装置所使用的原料煤煤质以及运行参数、性能指标进行分析,结果表明,气化炉产能、有效合成气成分、比煤耗、比氧耗等主要性能指标均优于设计值,无烟煤在本装置上的应用非常成功。     

ON THE SIMULTANEOUS REPRESENTATION OF VAPOR-LIQUID EQUILIBRIA AND EXCESS ENTHALPIES OF 1-ALKANOL + n-ALKANE MIXTURES

Simultaneous representation of vapor-liquid equilibria and excess enthalpies for l-alkanol + n-alkane mixtures has been investigated by means or the PRSV equation of state together with the Wong-Sandier mixing rule. Special attention has been paid on the mixtures of methanol and n-hexane. The results are influenced not only by the selection of a suitable excess Gibbs energy model incorporated in the mixing rule but also by the weighting factors used in the objective function for the evaluation of parameters.     

GE气化工艺高压黑水管线改造探讨

针对GE水煤浆气化普遍存在的激冷室至高压闪蒸罐,洗涤塔至高压闪蒸罐等高压管线的堵塞问题,分析原因,提出改进措施.     

PROFIBUS-DP总线在运输机控制系统中的应用

文章结合现场总线技术在成庄矿主运输机控制系统中的应用,着重介绍了PROFIBUS-DP总线在S7-400H、GE 90-70中的实现。展望了现场总线技术在自动化系统中的应用前景,介绍了在实际应用中应注意的事项。对现场应用此类总线有一定的指导意义。