新建锅炉化学清洗监督检验的探讨及应用

为确保锅炉的安全经济运行,化学清洗在锅炉上得到广泛应用。但是对于新建锅炉的化学清洗,锅炉使用单位往往不够自觉和重视。本文以对德清某电厂一台新建型号为UG-90/9.8-M的锅炉化学清洗的监督检验为例,就如何加强新建锅炉化学清洗监督检验的工作做了探讨和应用,具有一定的参考价值。     

新建超临界锅炉化学清洗监督检验的探讨

对于新建超临界机组锅炉,使用单位和施工单位往往不够重视特种设备检验检测机构对其化学清洗过程的监督检验,国家质检总局2010年颁布的《锅炉水(介)质处理监督管理规则》明文规定了锅炉的化学清洗过程监督检验属于法定检验。甘肃省某超临界机组锅炉在投运前进行的化学清洗监督检验是该省特检院第一次参与到的电站锅炉化学清洗监督检验项目,这次化学清洗监检工作的顺利完成,对于甘肃省今后如何加强新建电站锅炉化学清洗监督检验工作具有示范作用以及一定的参考价值。     

低温EDTA氨盐清洗工艺在超超临界锅炉的工程应用

从原理上简要描述了EDTA络合效应除垢机理,以天津某电厂新建3号、4号锅炉的清洗过程为例,详细描述了整个低温EDTA清洗和钝化过程,并对最终的清洗效果进行了评定。该工艺清洗效果优良,同时可以节省大量的燃油和除盐水,缩短了化学清洗工期,降低了劳动强度,是一种值得在新建超超临界锅炉中推广的新型化学清洗工艺。     

复合酸清洗在超超临界直流锅炉中的应用

针对超超临界锅炉特点及基建机组化学清洗的目的,按照国家能源局所发布的火力发电厂清洗导则的要求,通过介绍南方某电厂1号机组的化学清洗范围、清洗工艺过程和控制参数,分析和讨论了新建锅炉复合酸清洗过程中应注意的事项。     

锅炉化学清洗的回顾与思索(Ⅱ)

第三章锅炉的化学清洗剂锅炉在垢物附着的状态下,若长期运行则往往因炉管管壁过热和腐蚀而引起破损等事故。为了提高锅炉效率和安全管理,从预防事故的观点出发定期对运行锅炉和新建锅炉采用化学清洗方法,除去水垢及腐蚀生成物,使锅炉经常处于清洁状态,是十分必要的。了解各种锅炉化学清洗剂的性能,并掌握它们与被清洗垢物的反应机理是准确选择清洗剂的先决条件。一、盐酸盐酸是化学清洗中应用历史较长、广度较大的清洗剂。它能与二氧化硅以外的垢物成分发生化学反应,其反应生成物的溶解度大,且有良好的清洗操作性能。但因Cl-对奥氏体钢材往…     

锅炉化学清洗的回顾与思索（IV）

锅炉化学清洗的回顾与思索（ＩＶ）倪关龙（贵州电力试验研究所，贵阳５５０００２）第七章钝化技术目前，电站锅炉的化学清洗主要针对的是新建炉。为了防止新建炉在酸洗后金属表面与空气接触而发生氧腐蚀，必须用钝化药剂对其进行处理，在金属表面形成一层很薄的保护膜。...     

高温EDTA和柠檬酸化学清洗在新建机组中的应用

针对目前两种常用的高温EDTA铵盐和柠檬酸锅炉化学清洗工艺,对比分析了清洗工艺、清洗成本、清洗过程和清洗质量,通过在华润焦作电厂2×660 MW超超临界新建机组上的实际应用表明,EDTA清洗具有过程简单,易操作,清洗和钝化一步完成,清洗液p H 9左右,腐蚀总量较小,清洗质量安全可靠,钝化膜致密、较厚,清洗废液较少,有利于整启阶段水质改善等优点,更适合新建机组锅炉化学清洗。     

论锅炉化学清洗中的安全及防护

针对锅炉化学清洗过程中遇到的一些实际问题 ,对锅炉化学清洗的工作程序与要点进行了探讨 ,并对锅炉的化学清洗问题提出了一些建议     

300 MW燃煤电站化学清洗

介绍了哥伦比亚某电厂300MW燃煤电站新建机组2号锅炉投产前的化学清洗,采用先碱洗后柠檬酸清洗的工艺流程。酸洗结束后进行了结果分析,最后总结了酸洗过程中注意事项并提出了一些建议。     

提高电站锅炉化学清洗质量的几点建议

在火力发电厂电站锅炉化学清洗工作中 ,如何提高和保证化学清洗质量 ,使化学清洗质量上水平、上台阶 ,这是每一个化学清洗工作者所关心的问题。本文就电站锅炉化学清洗的实施中遇到的一些影响清洗质量的具体问题提出了几点改进措施 ,使化学清洗工艺得到了进一步的完善     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

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.