鞍钢铜冷却壁高炉操作炉型管理模型开发与应用

对鞍钢铜冷却壁高炉操作管理模型的建立方法进行了阐述,并对在2号高炉上的实践进行了总结.根据经验知识和实验室热态模拟实验结果,利用传热模型反推计算,建立铜冷却壁高炉操作炉型管理模型,可对铜冷却壁热面渣皮厚度进行实时计算,实现操作炉型管理.鞍钢2号高炉应用结果表明,铜冷却壁操作管理模型可对渣皮脱落部位、炉腰和炉身下部铜冷却壁热面温度和渣皮厚度变化趋势进行判断,提示操作人员及时采取措施,控制渣皮厚度适宜并保持稳定,减少铜冷却壁区域热损失,并保证高炉操作炉型合理.     

鞍钢3号高炉铜冷却壁破损调查

对鞍钢3号高炉铜冷却壁破损原因进行调查分析,认为渣皮稳定性差,铜冷却壁直接受到高温炉料、煤气流冲击造成磨损和氢脆侵蚀形成裂纹,是铜冷却壁破损的主要原因。     

首钢2号高炉铜冷却壁使用的体会

结合首钢2号高炉铜冷却壁使用的经验,重点阐述了铜冷却壁作为一种长寿、高效的冷却设备,铜冷却壁需要其热面的渣皮来实现对自身的保护。而铜冷却壁热面的渣皮对炉内煤气流分布的变化十分敏感,因此,稳定煤气流分布,实现渣皮的稳定,是铜冷却壁高炉稳定、顺行的关键。     

武钢铜冷却壁高炉炉墙结厚原因分析

对铜冷却壁在武钢大型高炉的应用情况进行了阐述。选取8号高炉为代表，对武钢铜冷却壁高炉炉墙结厚的过程进行跟踪分析，找出炉墙结厚的原因，并提出防止炉墙结厚、维护铜冷却壁高炉操作炉型的对策措施。边缘气流长期不足、操作制度未能适应入炉料结构变化、渣皮脱落后操作不合理是武钢铜冷却壁高炉炉墙结厚的主要原因。须通过十字测温和炉身热负荷管理办法，控制适宜的边缘气流，入炉料结构发生变化后要进行针对性调整，渣皮脱落后的煤气流控制要遵循疏通中心引导边缘的原则，才能从根源上消除铜冷却壁炉墙结厚现象，保持铜冷却壁高炉良好的操作炉型。     

高炉铜冷却壁取样研究及破损原因分析

 在整个高炉结构中,炉身下部至炉腰炉腹位置是影响高炉寿命最薄弱环节之一,铜冷却壁应用该区域可形成“渣皮”作为永久性炉衬,有效延长高炉中部寿命,实现了高炉高效和长寿的统一。然而,在生产实践中渣皮频繁脱落,铜冷却壁热面裸露,导致铜冷却壁大面积破损,严重影响生产。针对鞍钢某高炉铜冷却壁破损情况进行了简单的介绍;采用金相分析、扫描电镜及能谱分析和化学分析方法,对破损的高炉炉腰段铜冷却壁进行取样研究。研究结果表明：在高炉内服役过程中,铜冷却壁中氧含量偏高,在受到高温煤气流冲蚀后,在其热面产生了“氢脆”现象,这是造成铜冷却壁破损的根本原因。提出了防止铜冷却壁破损的建议。     

高炉铜冷却壁渣皮生长传热分析

建立了高炉铜冷却壁非稳态传热分析模型,利用ANSYS单元生死技术模拟了冷却壁表面的渣皮再生行为,分析了渣皮脱落后的生长规律及壁体温度和热负荷的变化过程。结果表明,渣皮生长遵循幂函数规律。经过计算,渣皮脱落0.9 min时铜壁测量点温度达到最高值59℃,经过23.5 min趋于稳定。铜冷却壁承受的最高热负荷为107.8 kW/m2,热面最高温度达到123℃。     

大型高炉铜冷却壁渣皮物相组成及性能分析

 高炉铜冷却壁热面形成的渣皮是保障冷却壁寿命的关键。基于高炉中修，针对铜冷却壁热面的渣皮进行实地取样，通过化学成分分析、XRD分析以及SEM EDS分析，并结合FactSage热力学计算及激光法导热分析，对大型高炉铜冷却壁表面形成渣皮的化学成分、微观形貌、高温性能和导热性能进行系统研究，探明了大型高炉铜冷却壁热面渣皮的物相组成和基础性能。结果表明，高炉铜冷却壁渣皮具有明显的分层结构，主要物相为二铝酸钙(CaAl4O7)、硅灰石(Ca2Al2SiO7)和钙长石(CaAl2Si2O8)等；通过FactSage软件计算渣皮熔化温度和黏度，发现沿着渣皮的生长方向，熔化温度降低，流动性降低；并通过传热计算得出合理渣皮厚度条件下的热流强度，从而为高炉生产实践提供理论指导。     

铜钢复合冷却壁稳态传热分析

建立了铜钢复合冷却壁的稳态传热模型,利用ANSYS单元生死方法模拟冷却壁表面渣皮熔化行为,分析冷却壁温度分布、渣皮厚度及热负荷。结果表明:复合冷却壁附近炉气温度是影响其传热行为和渣皮厚度的主要因素;渣皮在冷却壁表面分布不均匀,随着炉气温度升高渣皮不均匀性逐渐增加;提高水速和全铜质壁体可以有效降低壁体温度,但对热负荷、渣皮厚度影响较小;在炉气温度1 200~1 400℃范围内,复合冷却壁的铜壁最高温度为125℃,承受热负荷达到82.8 kW/m2,能够满足高炉高负荷区的冷却要求。     

高炉铸铁冷却壁极限热负荷的传热分析

通过建立高炉铸铁冷却壁的三维传热模型,应用渣皮熔化迭代方法分析冷却壁温度场,确定不同条件下冷却壁的极限热负荷,讨论了高炉冷却壁的结构和冷却工艺对极限热负荷的影响.结果表明,冷却水速度(2～4m/s)对极限热负荷影响较小,水管与壁体间的气隙降低了铸铁冷却壁冷却能力;冷却水管直径由φ48 mm增加到φ70 mm,可以使极限热负荷提高45%.     

新型冷却结构在1080m~3高炉上的应用

针对炉体高热负荷区域,基于铜冷却壁的优良性能,开发了一种炉体新型冷却结构,即在炉体高热负荷区采用铸铁冷却壁热面镶嵌铜冷却条。这种炉体新型冷却结构在1080m~3等多座高炉上应用效果表明,新型冷却结构具备冷却强度大、有利于渣皮稳定的特点,能够有效解决炉体高热负荷区域冷却设备损坏的问题,投资相对于铜冷却壁大幅降低,是一种经济而实用的新技术。     

1969 C.P.A. Institute.

Presents the program for the C.P.A. Institute entitled "The Role of Counseling Services on the Contemporary Campus." The Institute was held on June 2-3, 1969. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Laudatio: Prof. Dr. med. Dr. phil. Dres. h. c. Heinz H?fner

During the course of a year, there are many healthcare workers nationwide who sustain sharps injuries whilst carrying out their duties. Staff who work in the Accident and Emergency (A & E) units are no different from anyone else in this respect. The emotional cost of such an accident cannot be calculated, whereas the financial costs can. This article aims to show how the cost of an injury to a member of staff can be calculated, thus allowing a manager to assess the financial implications of sharps injuries to their department. In the absence of access to an Occupational Health (OH) department, most A & E units have to respond to sharps injuries to healthcare workers in the hospital. This task must be attended to by the medical staff as well as the nursing staff of the A & E unit. Within the following text the appropriate responses and methods to ensure uniformity of response are discussed. The tables and the calculation figures shown are taken directly from the information held in the St James's University Hospital Trust's OH department. All calculations are based on the middle band of the salary scale for each discipline. Accurate costings for each member of staff injured cannot be shown in this article, but the general principle is laid down and can be easily followed for any situation.     

Rats, Man . . .

Comments on the article by Richter entitled "Rats, Man, and the Welfare State" (see record 1960-02810-001). The commenter notes that in his article Richter did not indicate how hereditary and environmental factors were controlled. In comparing the hereditary survival characteristics of wild versus domesticated rats, it would be essential that the environmental influences on the survival characteristics of the wild rats should be ruled out. Another factor to be considered is that the wild state may offer a diet and other environmental influences, which in the life of a single individual would produce organic changes, accounting for some of the differences between wild and domestic rats. It would seem that the most effective way to determine the hereditary differences between wild and domestic rats would be to create a wild group, composed solely of the offspring of wild rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The blood-brain barrier. I. Histology. Physiology. Embryology. Transport

The concept of blood-brain barrier (bbb) arose in the beginning of the 20th century after report that the dyes injected intravenously did not appear in the brain. The idea and definition of bbb has been changed many times since then. We present current opinion concerning bbb, its histology, embryology, ultrastructure and function on the ground of a review of the recent literature.