烧结新技术在昆钢130m^2烧结机上的应用

昆钢2台130 m2烧结机承担着向2000 m3高炉提供烧结矿的任务。受多种因素影响,烧结矿产量、质量与2000 m3高炉的要求还有一定差距。通过技术改造和新技术应用,使130 m2烧结机的各项技术经济指标有了大幅度提高,取得了较好的效果。     

技术创新是大型矿山企业发展的动力源

梅山铁矿是大型地下矿山 ,属上海宝钢集团梅山公司的全资子公司 ,矿床地质储量 2 .6 2亿t,设计年采选综合生产能力 4 0 0万t。近年来 ,通过技术创新和科技成果的应用 ,增强了企业活力 ,创出了一条科技成果转化为生产力的新路子。1　优化采场结构参数　降低采矿成本梅山铁矿采用无底柱分段崩落法采矿 ,该矿结构参数经历了 10m× 10m小结构参数、 15m× 15m大结构参数、 15m× 2 0m大间距结构参数三个阶段的发展。 2 0世纪 80年代中期以前一直采用 10m×10m结构参数配置小型低效风动设备 ,导致全员劳动生产率低 ,年人均 86 2t ,采矿采准工程量…     

邯钢2号435m~2烧结机关键技术的研究与设计

邯钢现有1×400 m2、1×435 m2、2×90 m2、2×360 m2共6台烧结机,年产烧结矿1 800万t,铁产量达到1 300万t,根据公司规划和产业升级的要求,拟拆除东区2×90 m2烧结机建设2#435 m2烧结机。设计时结合国内外烧结技术的最新成果,对燃料准备、配料、水浴除尘、厚料层烧结、高效节能点火炉、环冷机、环保振动筛、主抽变频运行及联合拖动、活性炭烟气净化等关键技术进行了研究,以期实现高效、优质、低耗、环保的目标。     

本钢炼铁厂360m~2烧结机的设备改造

本钢炼铁厂有一台360m2烧结机,年产370万t烧结矿,为了解决高炉增产对烧结矿的需求。现采取了对360m2烧结机进行设备改造,来提高烧结机的产能,满足高炉的生产需要。经过充分的论证,于2009年10月26日对360m2烧结机开始进行设备改造,为期5天的施工,取得了360m2烧结机的设备改造的顺利完成。     

改性粉煤灰的制备及从烟气中吸收SO_2试验研究

研究了对粉煤灰进行改性并用以从烟气中吸收SO_2,考察了温度、m(Ca(OH)_2)/m(Na_2SiO_3·9H_2O)、液固体积质量比对粉煤灰改性的影响。结果表明:在m(Ca(OH)_2)/m(Na_2SiO_3·9H_2O)=2/1、温度80℃条件下,对粉煤灰改性14h,干燥2h,所得改性粉煤灰对烟气中SO_2的吸收量达137.998mg/g,吸收效果较好。     

冶炼烟气制酸净化工序改造实践

针对3.9m2熔炼炉和9 m2吹炼炉设计的制酸净化工序,采用绝热增湿稀酸洗涤工艺.为适应熔炼炉扩大到6 m2和吹炼炉扩大到11.2 m2的需要,对设备和工艺进行了局部改造和改进,最终实现了制酸与冶炼的配套,硫酸产量提高的同时减少了污酸排放量,节能减排效果明显.     

高频振动斜板浓密机在钼矿的应用研究

本次研究通过对现用Φ9 m浓密机安装高频振动斜板模块的技术改造,将其沉降面积由60 m2提高到120m2左右,将Φ9 m浓密机的溢流浓度降低到0.05%左右,解决了溢流水"跑浑"问题,减少了钼金属流失。     

酒钢本部450m~3、2500m~3高炉经济性对比

本文通过对酒钢本部450 m3、2 500 m3高炉指标、原燃料条件及生铁成本等进行经济性对比分析,本部450m3高炉由于使用了低价原料(特别是自产料),其成本远低于2 500 m3高炉,但通过对适应于2 500 m3高炉的同等原燃料条件下的对比测算,2 500 m3高炉的生产成本要低于450 m3高炉;高炉容积的选择需要从企业经营战略、原料条件、政策风险、未来市场预测结果等多方面进行考虑。     

攀钢260 m2烧结机优化设计与快速达产

攀钢烧结系统升级改造工程之一新建260 m2烧结机,结合先期建设的两台360 m2烧结机存在的问题,在建设场地狭窄、工艺流程复杂的条件下对260 m2机进行了改进优化设计,消灭了大量工艺、技术与设备缺陷,实现了快速达产达效,利用系数不断刷新历史记录,月达1．559t／m2．h的国内最高水平;通过优化改进工艺技术与参数,快速进入高产稳产阶段。     

新华钼业改造高能耗设备

新华钼业1系列φ2．7m×2．1m球磨机已服役多年,球磨机简体、端盖、中空轴等磨损严重,已到了使用年限,继续使用存在较大的安全隐患。日前,新华钼业选矿厂1系列φ2．7m×2．1m球磨机改造工程启动。由于该球磨机的传动系统轴瓦是乌金瓦,球磨机自重大,断油后轴瓦急剧升温,     

电除尘器在南(京)钢烧结机头烟气除尘中的应用

介绍了电除尘器在南京钢铁联合有限公司炼铁新厂180 m^2烧结机机头烟尘治理上的应用.分析了运行中存在的问题并介绍所采取的整改措施,总结了大型电除尘器用于烧结工艺除尘的经验.     

声波清灰器在烧结机头电除尘器中的应用

鞍钢炼铁总厂针对二烧烧结机机头电除尘器振打装置存在的问题，采用辽宁中鑫自动化仪表有限公司生产的声波清灰器作为辅助清灰器进行增效改造，取得了很好的效果。本文介绍了声波清灰的原理、特点、清灰系统的构成及使用效果。     

杭钢炼铁厂球团竖炉电除尘器脉冲供电试验

杭钢炼铁厂为了解决球团竖炉电除尘器因服务年限较长而产生的反电晕现象,采用脉冲供电方式进行了试验研究,取得了提高除尘效率的预期效果.     

电除尘器在马钢竖炉球团生产中的应用

介绍了马钢一烧3座球团竖炉的电除尘器系统及其运行情况。其中，1^#、2^#竖炉于2001年7月投产，2005年4月扩容为10m^2，并对其电除尘系统进行了改造。3^#竖炉于2004年5月投产，由于汲取了1^#、2^#竖炉的经验，其电除尘系统的设计和设备选型合理，投产顺利，取得了较好的效果。     

烧结电除尘器的工况分析与控制

对不同烧结工艺流程段，不同因素对电除尘器所产生的影响和对控制系统的要求进行了分析，对不完善的控制设备和方式的改进作了说明，介绍了一种利用Concept编程软件设计程序，采用烧结工艺现有的Quantum系列计算机对早期设计的电除尘器振打，卸灰实现自动控制。     

Distribution of prostaglandin E receptors in the rat gastrointestinal tract

AIMS: In order to study the role of prostaglandin in the regulation of the gastrointestinal functions, gene expression of prostaglandin receptors along the rat gastrointestinal tracts were investigated. METHODS: Rats were used for the study. The combination of counterflow elutriation separation of mucosal cells and Northern blot analysis was used to detect the gene expression of prostaglandin receptors in gastrointestinal tracts. RESULTS: In small intestine and colon, prostaglandin E2 EP1 and EP3 receptor mRNAs were mainly localized in the deeper intestinal wall containing muscle layers. EP4 receptor gene expression, on the other hand, was detected in the intestinal mucosal layer. In the stomach, EP1 mRNA was detected in gastric muscle layers, whereas EP3 and EP4 receptor gene expression was mainly present in the gastric mucosal layer containing epithelial cells. In gastric epithelial cells, parietal cells were found to have both EP3 and EP4 receptors. At lower concentrations, prostaglandin E2 inhibited gastric acid secretion by parietal cells probably through EP4 receptors. At higher concentrations, however, it stimulated it. On the other hand, mucous cells possessed only EP4 receptor mRNA. CONCLUSIONS: Thus, it is suggested that prostaglandin E2 modulates gastrointestinal functions through at least three different prostaglandin receptors (EP1, EP3, and EP4), each of which has a distinct contribution in the gastrointestinal tract.     

Growth regulation of primary human keratinocytes by prostaglandin E receptor EP2 and EP3 subtypes

We examined the contribution of specific EP receptors in regulating cell growth. By RT-PCR and northern hybridization, adult human keratinocytes express mRNA for three PGE2 receptor subtypes associated with cAMP signaling (EP2, EP3, and small amounts of EP4). In actively growing, non-confluent primary keratinocyte cultures, the EP2 and EP4 selective agonists, 11-deoxy PGE1 and 1-OH PGE1, caused complete reversal of indomethacin-induced growth inhibition. The EP3/EP2 agonist (misoprostol), and the EP1/EP2 agonist (17-phenyl trinor PGE2), showed less activity. Similar results were obtained with agonist-induced cAMP formation. The ability of exogenous dibutyryl cAMP to completely reverse indomethacin-induced growth inhibition support the conclusion that growth stimulation occurs via an EP2 and/or EP4 receptor-adenylyl cyclase coupled response. In contrast, activation of EP3 receptors by sulprostone, which is virtually devoid of agonist activity at EP2 or EP4 receptors, inhibited bromodeoxyuridine uptake in indomethacin-treated cells up to 30%. Although human EP3 receptor variants have been shown in other cell types to markedly inhibit cAMP formation via a pertussis toxin sensitive mechanisms, EP3 receptor activation and presumably growth inhibition was independent of adenylyl cyclase, suggesting activation of other signaling pathways.     

Technical features of a CCD video camera system to record cardiac fluorescence data

Prostaglandin E2 (PGE2) is a potent local mediator of cell growth and differentiation in various tissues. The receptors for PGE2 have been classified into four pharmacological subtypes, EP1, EP2, EP3, and EP4, based on the responses to selective agonists and antagonists. We have cloned a functional cDNA for the rat EP2 receptor subtype from a rat lung cDNA library. The rat EP2 receptor cDNA encodes 357 amino acid residues having high homology with the human and mouse EP2 receptors and containing seven putative transmembrane domains. In COS-7 cells transfected with rat EP2 cDNA, specific [3H]PGE2 binding was found with a dissociation constant of 14.9 nM, and this binding was inhibited by unlabeled PGE2 and PGE2 alpha. PGE2 and butaprost, an EP2 selective agonist, were effective in increasing the cAMP level in the COS-7 cell transfectants. Northern blot and RT-PCR analysis showed widespread distribution of the EP2 receptor in various tissues. Higher EP2 expression was found in fetal long bones and calvariae than in adult by RT-PCR and in situ hybridization, suggesting a role for this receptor in rapidly growing skeletal tissue.     

烟气静电除尘系统的运行与控制

以具体静电除尘系统为例，详尽地探讨了电压电源控制系统特性，讨论了系统故障处理方法，针对提高除尘效率问题提出了一些切实可行的方法和建议。     

Prostaglandin E2 receptor subtype EP2 gene expression in the mouse uterus coincides with differentiation of the luminal epithelium for implantation

Among the PGs, PGE2 is considered especially important for implantation and decidualization. Four major PGE2 receptor subtypes, EP1, EP2, EP3, and EP4, mediate various PGE2 effects via their coupling to distinct signaling pathways. Previously, we have shown that the EP1, EP3, and EP4 genes are expressed in the periimplantation mouse uterus in a spatio-temporal manner, suggesting compartmentalized actions of PGE2 during this period. In this study, we examined the expression of the EP2 gene in the mouse uterus during the periimplantation period (days 1-8) and during experimentally induced progesterone (P4)-maintained delayed implantation and its resumption by 17beta-estradiol (E2). We also examined its regulation in the uterus by ovarian steroid hormones. Our results establish that EP2 messenger RNA (mRNA) is expressed exclusively in the luminal epithelium primarily on day 4 (the day of implantation) and day 5 (early implantation) of pregnancy. In (P4)-maintained delayed implanting mice, EP2 mRNA was present in the luminal epithelium, and the expression was further enhanced regardless of the location of the blastocysts after reinitiation of implantation. This observation suggests little or no embryonic influence in regulating EP2 expression and, instead, shows its regulation by P4 and E2. Indeed, treatment with E2 and/or P4 exhibited unique regulation of this gene. The treatment of adult ovariectomized mice with E2 down-regulated the basal levels of EP2 mRNA, whereas that with P4 up-regulated its levels in the luminal epithelium. The up-regulation of EP2 mRNA levels by P4 was further augmented by superimposition of the E2 treatment, suggesting a synergistic interaction between E2 and P4 in regulating this gene in the uterus. Collectively, the results suggest that EP2 could be a potential mediator of PGE2 actions in regulating luminal epithelial differentiation and serve as a marker for uterine receptivity for implantation.