长输管道事故案例统计分析及对策研究

管道的安全平稳运行,对于油气资源的运输具有重要的意义。本文对近年来国内外油气道事故数据进行统计分析,为我国长输油气管道的事故分析、事故诊断与预测提供了参考。得出的结论:国内油气管道失效的主要原因为腐蚀、外部因素和材料缺陷,同时给出了相应的对策:完善法律法规、加强区域宣传;提高设计验收质量、强化运行管理;采用先进的施工技术和管道材质。     

国外管道失效数据库简介及参考

管道失效数据库在管道完整性管理实施和安全监管方面起着重要作用,介绍了国外PHMSA、EGIG、Concawe、NEB等管理机构成熟运行的管道失效数据库,从数据库的统计范围、事故上报、事故统计等方面分析了不同国家管道失效数据库的差异和对我国数据库建设的参考。     

油气管道失效与风险评估

石油及天然气通过管道运输是最为经济合理的运输方式。但是石油及天然气具有易燃易爆,有毒的性质严重影响了管道的安全运行。当油气管道经长时间使用之后,会由于外部干扰,腐蚀以及管材施工具体质量造成严重油气管道失效问题。甚至会发生火灾,爆炸,中毒等事故,造成重大人员伤亡及经济损失。在油气管道失效事故发生之后,要深入的分析失效模式,机理以及明确原因,以防止此类事故再次发生。同时对油气管道进行风险评估也是一项重要的工作。对于同一管道系统中的不同管段进行风险评估,可深入了解管道的薄弱环节,掌握风险工作的最佳时机,避免事故的发生。本文主要讲述了油气管道的失效现象以及风险评估,进一步降低了油气管道事故的发生。     

基于改进Bow-tie模型的动力管道风险分析

通过人为、自然、设备和管理4个因素分析动力管道失效原因,把动力管道失效所带来的后果划分成安全、经济、环境和社会4个方面进行分析,确定了动力管道泄漏的防控措施。运用改进Bow-tie模型分析动力管道失效问题,有效降低了管网事故发生率。     

海底管道完整性管理研究进展

海底管道服役条件苛刻,发生事故会对生态环境造成较大影响,采用完整性管理对提高海底管道运行安全性具有重要意义。统计了国内外近14年所发生的海底管道事故,并对事故原因进行分析发现导致海底管道失效的原因有有第三方破坏、腐蚀、设计缺陷、误操作及自然环境因素。调研了海底管道完整性管理标准发展现状,以及海底管道风险评价技术。分析了国内完整性发展,表明国内对海底管道完整性管理的研究较为零散,还没有形成完整的管理体系,开展的管道完整性管理多应用于陆上管道,而海底管道的完整性管理研究还不够系统。     

基于优化贝叶斯网络的油气管道失效风险安全评价

为提高油气管道失效风险评价的准确性,提出了基于蝴蝶结-优化贝叶斯网络模型的动态分析方法。采用蝴蝶结模型对油气管道的失效原因和管道失效后引发的事故后果进行了分类,利用噪声门模型和专家判断对贝叶斯网络进行优化,引入时间维度构建动态贝叶斯,通过实例对管道失效事故的易发性和后果严重性进行计算。结果表明,评价管道的失效概率为7.32×10^-3次/(km·a),后验概率中土层运移、管线标注不明确、介质中含有腐蚀物和介质中含有砂粒等因素是管道失效的关键因素;管道失效概率在1～2个时间步内的数值较大,风险较大;事故后果中燃爆风险大于扩散风险大于无后果风险,事故后果发生概率随时间步的增加而减小。     

油气管道全生命周期安全监测预警探析

基于国内外油气管道安全事故统计分析,指出管道事故主要致因为外部干扰、腐蚀、材料失效以及自然灾害,其中第三方损坏是我国管道失效事故首要因素,提出应开展全生命周期管道安全监测预警进行风险防控,从源头做好风险防控和失效防护;分析国内外管道安全监测预警技术与管理现状,探讨监测预警技术对全生命周期管道安全监测预警的适用性、可行性、经济性,提出光纤传感、声波、视频安防、地质灾害监测、腐蚀监测等对油气管道风险防控具有较高的适用性和经济性;应加强管道安全预警技术性能评估方法和适用性准则研究,建立涵盖技术选择、系统设计、建设施工、运行评价的综合监测预警管理体系和运行机制,并有效纳入管道完整性管理体系范畴。     

故障树分析山东天然气管道失效概率

本文以山东管道为例,对引起长输管道失效的内因和外因进行分析。首先根据引起管网失效的四个最直接的原因(第三方破坏,管道腐蚀,管道材料缺陷和管道附属设备失效)展开分析,用故障树对山东管道失效进行定性分析,确定故障树的最小割集,找出事故发生的薄弱环节。其不仅可以作为编制HSE检查表的重要依据,同时故障树分析的结果可为山东管道老管网的维护和济青二线的设计提供理论指导,又可达到预测和预防事故发生的目的。     

废碱液管道腐蚀穿孔失效分析

某石化企业的一根废碱液管道发生腐蚀穿孔失效,对其进行了失效分析.通过研究,认为该管道发生的腐蚀类型为局部点腐蚀.引起点蚀的主要原因有材料本身存在不足,介质的流速相对缓慢及管道间歇运行、介质停留时间较长.     

浙江省级天然气管道第三方破坏失效概率计算方法探讨

第三方破坏不仅取决于管道自身条件,而且还受外部环境、运行管理条件的直接影响,所引起的管道失效概率具有很强的随机性。本文对欧洲输气管道失效数据库提供的相关失效数据进行线性回归分析,结合浙江省级天然气管道运行情况,基于风险评估第三方破坏评分体系与权重确定方法,综合考虑管道环境和运行管理条件,提出了管道第三方破坏失效概率预测模型。运用VB语言编制了计算程序,对8条管线进行计算,计算结果表明:对浙江省级天然气管道失效概率影响最大的因素是管径、壁厚和埋深。所建立的预测模型可作为评判输气管道第三方破坏的量化指标,为浙江省级天然气管道的运行、维护和检测提供参考依据。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。