沸腾炉壳体腐蚀与温度保护

一般硫酸沸腾炉设计都采用钢板外壳,内衬耐火砖,中隔绝热砖。如南化设计院设计的年产8万吨的硫酸沸腾炉外壳钢板厚12毫米、耐火砖厚320毫米、绝热砖厚80毫米;罗马尼亚年产20万吨硫酸沸腾炉外壳钢板厚12毫米、耐火砖厚230毫米、绝热砖厚150毫米(据罗马尼亚考察报告);宁波硫酸厂年产5万吨硫酸沸腾炉外壳钢板厚12毫米、耐火砖厚140毫米、绝热砖厚113毫米。其实砖砌炉衬无论施工质量多么好,炉子投产时间一长,开停次数一多,炉衬受到热胀冷缩,砖     

100kt/a硫酸装置沸腾炉的设计

介绍100 kt/a硫酸装置沸腾炉的设计,包括原料组成、沸腾炉参数选择及结构特点。炉体采用外保温、球形拱顶、溢流口高度可调节、炉温也可灵活调节,炉壳材质选用16Mn钢,风帽采用ZGCr28的侧孔球顶承插式结构。沸腾炉投入使用后,由于入炉原料含水量高于设计值,沸腾层温度较低(770℃),炉气出口温度为850℃,但硫烧出率仍优于设计指标(98．5％),达到98．7％。实践证明,沸腾炉可满足生产需要。     

用沸腾炉飞灰代煤代土生产硅酸盐水泥

<正> 到1992年我国每年由沸腾炉燃烧排出的废渣将超过1000万 t,其中由烟道排出的飞灰就有200～350万 t。为解决由沸腾炉燃烧排放废渣而带来的各种问题,中国统配总公司将“利用沸腾炉烟道飞灰代煤、代土生产水泥”列入国家“七五”攻关课题。通过几年的试验、工业试生产,该课题已于1990年10月通过了由中国统配煤矿总公司组织的“七五”国家攻关课题的技术鉴定。为沸腾炉烟道飞灰的利用开辟了一条新途径。一、原料的来源及其性质利用沸腾炉烟道飞灰代煤、代土生产水泥,就是以飞灰代替水泥配料中的粘土,同时利用其中未燃尽的煤,以减少煤的配入量。沸腾炉飞灰外观呈灰黑色,粒度约0.02～0.6     

硫铁矿沸腾炉改烧硫磺的原料预处理技术

为使硫铁矿制酸沸腾炉能够满足烧硫磺的要求,以降低制酸成本,介绍将硫磺与硫铁矿尾渣或与低品位硫铁矿粉按比例混合,再添加一定量的改性剂,经过加热、造粒、化工水冷钢带冷却,产生的颗粒具有足够的强度,可满足硫铁矿沸腾炉制酸的需要。40kt/a硫酸投资仅需100万元,并可根据市场原料行情灵活运用。     

沸腾焙烧炉废热利用的概况

硫化精矿的沸腾焙烧,产生大量的过剩热能,冶金计算表明,焙烧一吨锌精矿所产生的剩余热能,可以产生0.6—0.7吨蒸汽。由此可见,合理利用沸腾焙烧炉的废热是降低生产成本的有效途径之一。 我厂于1958年改建沸腾焙烧炉以后,即着手进行一系列的废热利用试验工作。首先在硫铁矿沸腾焙烧炉上进行炉气废热锅炉的工业试验。通过几次的设备改进之后,已成功地生产2—4公斤/厘米~2的低压蒸汽,随后又进行锌精矿沸腾焙烧炉沸腾层废热和炉气废热利用的试验工作,并将炉气废热生产1-3公斤/厘米~2的蒸汽用于生产,初步计算全年可给国家节约煤炭7200吨,价值11万元。     

硫铁矿制酸沸腾炉的建筑及使用经验总结

<正>沸腾炉是硫铁矿制酸装置的关键设备,俗称"龙头"。沸腾炉设计、制造、安装及筑炉的好坏直接关系到沸腾炉是否能够稳定、高效运行。沸腾炉设计、制造、安装及筑炉如有问题,轻则不能开车,重则可能出现塌炉等事故。此外,沸腾炉的操作也很有讲究。只有合理设计、优良施工、精心操作,才能确保沸腾炉安全、稳定、长周期运行。下面笔者结合多年来沸腾炉设计和使用经验,谈一些沸腾炉安装、筑炉及使用中的注意事项。     

沸腾式高效节能炉在Φ2.2×12m转筒烘干机上的应用

我厂于1992年2月将φ2.2×12m矿渣烘干机的层燃炉改为沸腾炉。经过一段时间的使用,证明效果比较好,经济效益明显提高,每年可节省20万元左右,现将有关改造情况作一简要介绍。 1 沸腾式高效节能炉的工艺布置和结构沸腾炉结构示意图如图1所示。外加仪表控制部分,图中没有示出。炉体外层采用红砖砌成1·b·h,m:5.76×3.80×5.50,内层用高铝质耐火材料砌筑,炉体外用特制的钢架加固,整个     

高温沸腾炉结渣原因及消除方法

沸腾炉是水泥厂回转式烘干机的主要热源,其结渣现象相当普遍,原因也比较多,既有炉体结构如炉床面积、风帽出风角度等因素,也有操作管理如炉内温度、空气动力条件、风速、风压等因素.因此,要消除沸腾炉结渣,需根据燃料特性从炉体结构和操作管理两个方面来适应沸腾燃烧的物理化学反应.本文通过高温沸腾炉结渣的原因分析,结合节煤型高温沸腾炉的应用实践,提出消除结渣的方法.……     

江铜-瓮福400 kt/a硫铁矿制酸装置沸腾炉的工艺设计

介绍400 kt/a硫铁矿制酸装置沸腾炉的工艺设计.该装置采用两头一尾工艺,焙烧部分为2×200 kt/a双系列布置.考虑到装置原料粒度较细(200目以下的颗粒占94.3%),根据一般设计原理和某现有大型硫铁矿沸腾炉的生产实践,最终选定沸腾层操作气速1.12 m/s,折算为焙烧强度12.39 t/(d*m2),沸腾层温度850 ℃,炉气停留时间13.2 s,沸腾层高度1 400 mm,二次风调节范围0～10%.沸腾炉投入运行后,各项指标达到设计要求.     

用耐火混凝土代替耐火砖制沸腾炉内衬

陕西省华县磷肥厂硫酸车间,设计规模为1万吨/年。所用沸腾炉为一次扩大型。用耐火砖作沸腾炉内衬需用异形砖品种多,数量少,不易订到货,使建设进度受到影响。耐火混凝土作炉内衬,国内外介绍资料颇多,用于硫酸沸腾炉内衬,外地已有使用,但我省尚无先例。为了加快施工进度,我们结合具体情况,吸取外地经验,选用了以耐火混凝土代替耐火砖作沸腾炉内衬,于1978年9月建成投产,经五个月左右运行,未发现导常变化,但最终结果,尚待进一步考察。现将混凝士配方及施工情况介绍于     

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.     

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.     

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。