浅谈粒化高炉矿渣粉在水泥生产中的应用

粒化高炉矿渣粉是一种性能优良的水泥活性混合材,矿渣粉的加入对改善水泥性能及同外加剂的适应性、降低水泥水化热、提高水泥强度等方面有积极作用,并具有良好的经济效益。不同水泥品种(P·C32.5R、P·O42.5)矿粉的适宜掺加量需通过试验确定,同时要解决掺加矿粉后水泥早期强度下降较大的问题;平衡好各品种水泥在市场的定位和比例分配问题;平衡好矿粉掺量、水泥性能和效益三者的关系。     

利用SP炉灰替代石子、矿渣粉生产P·O 42.5水泥的试验

SP炉灰替代6%～8%石子生产P·O42.5水泥3天强度略微降低,凝结时间影响较小,3天强度下降,但不影响水泥的使用。SP炉灰替代部分矿粉28天强度下降幅度较大,可考虑掺加2%替代等量矿粉。     

C50高强混凝土配合比的优化研究

对C50高强混凝土所用水泥品种以及外掺料的选取展开研究,从而实现C50高强混凝土的配合比的优化。结果表明:C50高强混凝土最优水泥品种为P·O42.5;矿粉对C50混凝土的配合比较为不利;粉煤灰单掺混凝土抗压强度分别比矿粉单掺以及无掺合料混凝土提高了11.3%和8.5%,最优混凝土掺合料为粉煤灰;粉煤灰与矿粉作为混合掺合料时混凝土抗压强度值最低,粉煤灰与矿粉作为C50高强混凝土掺合料最为不利。     

粉煤灰-矿粉复合超细粉制备及其在水泥中的应用试验研究

将煤粉炉粉煤灰、循环流化床粉煤灰和S95矿粉分别进行超细粉磨，按照不同比例复合配制粉煤灰-矿粉复合超细粉，研究复合超细粉的粒度分布、活性指数和流动度比，以及复合超细粉替代一定比例成品P·O42.5水泥后水泥的标准稠度用水量、凝结时间和力学性能。结果表明，煤粉炉粉煤灰、循环流化床粉煤灰及矿粉分别经超细粉磨后，中位粒径分别为4.632 μm、2.611 μm和6.039 μm，循环流化床粉煤灰粒度更细。粉煤灰-矿粉复合超细粉的活性指数和流动度比均满足S95矿粉、甚至S105矿粉技术要求。粉煤灰-矿粉复合超细粉替代25%成品P·O42.5水泥，复合水泥标准稠度用水量和初凝时间略增加，复合水泥3 d和28 d抗压强度明显提高。     

水泥粉磨系统产能优化

正青州中联水泥有限公司1号水泥磨系统,P·O42.5水泥不掺加矿粉最优台时产量145t/h,电耗指标在34k Wh/t,水泥粉磨工艺及装备对水泥生产效率及效益影响较大,为提高水泥工艺装备水平,进一步节能降耗,并满足水泥市场黄金时期出厂量要求,我们对其进行了系统优化和改造。系统工艺流程见图1。     

一次P·O42.5水泥3 d强度下降的原因分析

我公司下属一水泥企业某段时间内,P·O42.5水泥3d抗压强度突然由30MPa降至29MPa以下。为此,通过原因调查分析,找到了P·O42.5水泥天然石膏掺量过低(SO_3含量约1.9%)是水泥早期强度下降的主要原因,在增加1%天然石膏掺量后,P·O42.5水泥SO3含量由1.91%提至2.11%后,3d抗压强度达30.7MPa,且其他性能指标无负面影响,恢复了内部生产较优水平。     

出磨水泥氯离子含量超标问题原因分析和处理

针对一起P·C 42.5出磨水泥氯离子含量超标问题进行原因分析,主要针对新供应的助磨剂和脱硫石膏中氯离子含量进行检测,确认是脱硫石膏氯离子含量过高超标导致。随后采取掺加矿粉和降低脱硫石膏掺配比例、新换氯离子含量低的脱硫石膏作缓凝剂等措施降低P·O42.5出磨水泥中氯离子超标不合格问题。     

磷石膏在普通硅酸盐水泥生产中的应用

磷石膏与脱硫石膏搭配生产P·O52.5、P·O42.5(R)水泥,虽然1d强度有所降低,但后期较高。掺加一定比例的磷石膏可以改善夏季高温季节水泥凝结时间与外加剂适应性的问题。     

陶瓷球与联合粉磨系统适应性问题的探讨

为降低生产成本，实现节能减排的要求，海螺集团多家子公司在联合粉磨系统开展了陶瓷球的应用实践。本文介绍其中一家公司Φ4.2 m×14.5 m水泥磨使用陶瓷球研磨体后，电耗降低超过12%，年用电量节省689.49万kWh的经验。同时，文章对于不同产地熟料、相同产地熟料对陶瓷球运行的影响进行了分析研究，得出生产P·C32.5R水泥时陶瓷球的适应性要好于生产P·O42.5水泥，生产P·O42.5水泥时矿粉掺入使用后对陶瓷球级配状况适应性优于粉煤灰的结论。     

镁渣用作水泥混合材的实践

从试验结果来看,P·O42.5级水泥生产时掺加5%~10%镁渣最适宜,质量均满足GB175-2007标准要求。同时考虑到要生产满足标准要求的其它通用水泥品种,工业生产时的镁渣掺加量上限要控制在10%。实践证明:镁渣作为水泥混合材,只要掺量适当,能提高水泥的易磨性和磨机台时产量,还能降低水泥生产成本;水泥比表面积有较大增加,强度有所提高,各项指标均能完全达到GB175-2007标准的要求。     

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。