水泥窑烟气SCR脱硝技术应用

水泥行业超低排放政策实施,水泥窑烟气氮氧化物深度治理是实现超低排放的核心技术之一。西矿环保结合中国水泥窑工艺特点,领先开发出"高温电除尘器+SCR脱硝一体化技术",具有低阻高效的显著优点。西矿环保已取得全国首台套水泥窑SCR脱硝技术示范工程业绩并成功投运,氮氧化物排浓度放稳定达到50mg/Nm~3以下,对我国水泥氮氧化物深度减排具有重要的引领示范作用。     

水泥窑烟气脱硝治理工艺技术探讨

通过水泥窑烟气特点,系统阐述水泥窑烟气脱硝工艺技术,从燃烧前、燃烧中及燃烧后烟气脱硝技术特点出发,说明各种脱硝技术优缺点,提出适合水泥行业烟气脱硝深度减排技术路线,以满足水泥行业日益严格的烟气氮氧化物排放标准。     

SCR脱硝技术在水泥工业中的应用分析

从如今的大气污染现状来看，氮氧化物是主要的污染物之一，其会严重地破坏地球自然生态环境，并对人的健康带来极大危害，因此当前各个工业行业都在极力探索高效的脱硫技术，以有效控制和减少氮氧化物排放。水泥生产工业会产生和排放出大量的氮氧化物，是位列火力发电、汽车尾气之后的第三氮氧化物排放大户。面对这样的情况，应加强SCR脱硝技术在水泥工业中的应用与推广，借助SCR脱硝技术的优势，在水泥生产过程当中，实现超低的氮氧化物排放。阐述了氮氧化物的危害及当前水泥工业的氮氧化物排放现状，介绍了SCR脱硝的技术原理，就SCR脱硝技术在水泥工业中的应用布置方案进行了分析，希望能对SCR脱硝技术的推广起到促进作用。     

水泥窑烟气SCR脱硝超低排放领先技术 西矿环保中高温SCR脱硝技术与工程

正西安西矿环保科技有限公司(简称西矿环保)凭借多年来对水泥窑烟气治理技术及水泥生产工艺的研究,自主开发的"高温电除尘+SCR脱硝技术"于2018年9月在河南登封宏昌水泥5000t/d生产线上成功运用,烟气出口NO_x排放浓度小于50mg/Nm~3,氨逃逸小于3ppm,成为我国水泥工业氮氧化物超低排放示范工程。"高温电除尘+SCR脱硝技术"不仅实现了SCR脱硝装置与水泥窑系统的有机结合,还突破了SNCR脱硝技术低效和氨逃逸量大的现状,是我国水泥工业走"生态水泥绿色发展"之路的关键技术。     

水泥窑烟气脱硝技术现状及展望

近年来,国家对水泥企业脱硝减排的要求越来越严格,现有条件下的烟气脱硝治理迫在眉睫。结合水泥窑NOx的来源和现有水泥窑脱硝技术及其运行效果,介绍国内外水泥窑SCR脱硝工艺布置形式及其应用现状,展望未来水泥窑烟气脱硝技术的源头治理、过程控制和末端治理的三个发展方向与可作重点开发的几种新技术。     

浅谈水泥行业脱硝技术应用现状

水泥行业已被列为"十二五"氮氧化物减排的重点领域之一。文章主要介绍了水泥行业氮氧化物的排放现状以及现行的脱硝技术,列举了部分脱硝技术应用实例。     

火电厂氮氧化减排及SCR烟气脱硝技术

氮氧化物排放中最多的类型企业是火电厂,同时我国每年的火电厂的数量和装机容量持续增长,这是最主要的原因。我国针对火电厂的情况,在2010年—2011年这两年内出台了新的排放标准和政策。在此之后我国不断的研发火电厂的SCR烟气脱硝技术。在该技术取得一定成绩后,我国火电厂的SCR烟气脱硝设备的数量在持续的增长。从而实现降低氮氧化物的目标。因此我国氮氧化物排放量最高的年份是在2011年,之后每年的氮氧化物排放量数值都在降低。讲解火电厂对氮氧化物的减排的技术,其中主要讲解SCR烟气脱硝技术的相关理论和流程。体现出SCR烟气脱硝技术是我国火电厂氮氧化物减排技术中的核心技术。     

SCR脱硝系统工艺方案设计及影响分析

分析了水泥窑烟气特性和SCR脱硝系统运行后对水泥窑及余热发电系统的影响，针对实施SCR脱硝的难点，确定采用“高温高尘”SCR脱硝工艺技术路线,以实现窑尾氮氧化物的超低排放。采用“高温高尘”SCR脱硝系统工艺方案，氮氧化物排放浓度可从300mg/Nm³降低至45mg/Nm³，达到超低排放要求，氨逃逸浓度<5mg/Nm³，吨熟料生产成本预计增加4.25元，余热发电系统总发电量预计减少0.67%。     

SCR脱硝技术在水泥厂熟料生产线使用效果分析

随着环保形势的严峻,工业氮氧化物排放标准会日趋严格,水泥行业将面临更加严峻的挑战。本文介绍了高温高尘SCR脱硝技术的工艺原理、设施布置,及在水泥熟料生产线的实际应用效果。通过对SCR脱硝技改后实际运行数据采集分析得出：水泥窑尾烟气采用高温高尘SCR脱硝技术,容易实现脱硝超低排放标准,且能降低氨水用量,节约生产成本;为消除SCR对系统阻力的升高,减小对系统操作的影响,吨熟料电耗会有所上升。     

蜂窝式SCR催化剂在水泥工业烟气脱硝超低排放应用现状探讨

SCR技术作为高效、成熟的烟气脱硝技术，在燃煤锅炉、钢铁等行业具有广泛应用。随着各地大力推进水泥行业烟气超低排放改造，SCR脱硝技术在水泥行业的应用得到逐步推广。本文比较了水泥与燃煤锅炉烟气特点的差异，总结了SCR脱硝技术在水泥工业应用中存在的挑战，分析了目前蜂窝式SCR催化剂在水泥工业烟气脱硝工程方面出现的常见问题，并提出了相应的解决方案和建议。     

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.     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.