高炉炉料运动过程数学模型的建立及其数值模拟

建立了高炉炉料一维非线性动力学数学模型,通过对其进行归一化处理,得到了反映煤气粘性力、炉墙摩擦力、渣水及铁水浮力等对炉料运动影响的６个准数．用该简化模型可得到与其它模型相同的结果．应用该模型计算了不同孔隙度炉料相应的临界煤气流速度和临界压力．研究了实际煤气流速度与临界煤气流速度之差对炉料运动过程的影响,给出了控制炉料稳定顺行的煤气流速度．     

中钛型钒钛磁铁矿矿焦混装试验研究

目前针对钒钛磁铁矿高温冶金性能的研究多集中在攀钢高钛型钒钛磁铁矿,中钛型钒钛磁铁矿的研究相对匮乏。高炉冶炼中钛型钒钛磁铁矿存在如透气性差、V收得率低等问题。为提高中钛型钒钛磁铁矿的高炉冶炼水平,系统考察了矿焦混装对中钛型钒钛矿综合炉料的软化区间、熔融区间、软熔带、收缩率、料柱透气性以及V收得率的影响。结果表明:当混装率在0～50%时,随着混装率的提高,综合炉料的软化区间变窄,熔化区间先变窄后加宽,软熔带位置下移,V的收得率先降低后升高;当混装率超过50%后,软化区间变宽,熔化区间变窄,软熔带区间明显变窄且位置下移,V的收得率先降低后升高。料柱透气性随混装率升高而明显改善。综合考虑软熔滴落性能和V的收得率等因素,确定适宜的矿焦混装率为50%。     

高炉炉料运动过程数学模型的建立其数值模拟

建立了高炉炉料一维非线性动力学数学模型，通过对其进行归一化处理，得到了反映煤气粘性力，炉墙摩擦力、渣水及铁水浮力等对炉料运动影响的６个准数。用该简化模型可得到与其它模型相同的结果。     

未来的高炉炉顶装料设备

高炉炉顶的钟式装料设备的缺点很多,如大小钟的制造,运输,安装,检修都很困难,使用过程中容易变形。若取消大钟、小钟,改用一个旋转溜槽向炉内布料,不仅从根本上免除了上述料钟式装料设备的缺点,而且能按冶炼需要将炉料分布于炉喉内的任意点,消除了炉料对炉墙的剧烈冲击。这种新型炉顶装料设备(简称旋转溜槽式)首先是由卢森堡的Wurth厂设计出来的。该设备1970型的试验模型见图1所示。它是一个生产模型,用来研究炉料从料斗通过溜槽向代表炉喉区的4扇形区布料的情况。它主要的特点是:有两个装有转阀和炉料流量控制阀的闭锁料斗,一个中心下料管,一个在布料时可调节斜度的溜     

高炉铜冷却壁破损分析与处理

本钢新1号高炉有效容积4747 m3,炉腹至炉身下部采用铜冷却壁冷却,炉腰部位铜冷却壁在生产中渣皮稳定性差,脱落频繁,在生产不到6年后出现大面积破损,被迫多次休风,威胁到高炉安全生产。通过分析发现,炉腰铜冷却壁受到高温炉料、煤气流冲击造成磨损;操作制度造成软熔带根部过低;铜冷却壁应力影响渣皮等原因是冷却壁破损的主要原因。经过研究,提出了改用雾化冷却、插入微型铜冷却棒、炉皮强制打水等解决方案。改造后,保证了安全生产,取得了良好的效果,但如果从根本上解决破损问题,应空料线停炉更换冷却壁。     

基于ANSYS的高炉炉墙温度场分析

通过建立高炉炉墙在多类边界条件下的计算模型,利用有限元分析软件ANSYS对高炉炉墙进行三维稳态温度场的分析计算。模拟了高炉炉墙、冷却板的温度分布状态,得出了炉渣渣皮厚度和炉墙热电偶温度之间的对应关系,为高炉操作提供了判断依据,确保高炉生产的稳定、顺行。     

平台宽度对高炉径向料层分布影响的试验研究

基于相似性原理,建立了按500 m3高炉1∶6比例缩小的180°无钟炉顶模型。利用该模型模拟了高炉炉喉料面的形成过程,并分析了不同布料制度下高炉径向料层分布的规律。结果表明,边缘平台是在相邻两档焦炭布料量差距较大时形成的,边缘平台越宽,在中心漏斗区加入矿石越多,高炉中心混合层越小,高炉中心气流环带越窄。各高炉根据原料条件和设备条件应有一个大小最优的混合层,混合层合适的宽度范围为15%~30%。不同布料制度下边缘平台区域和中间区域的径向气流速度分布和径向矿焦比分布存在比较好的对应关系。而在高炉混合层区域径向矿焦比均较小,此时径向气流速度分布与径向矿焦比关系不明显,但与径向粒度大小的关系较明显。在高炉次中心平均粒度较大,气流速度较大;高炉正中心平均粒度最小,气流速度也最小。     

川崎钢铁公司十年炼铁研究的进展

高炉炼铁的重要课题,是在维持稳定生产的同时降低生产成本。川崎把炉料分布控制作为可以稳定生产、大量使用细粒原料、达到较高生产率的重要技术。 为了大量使用细粒炉料,需要采用可将不同粒度和质量的炉料分别从炉顶装入的多批装料系统。因此,开发了3个平行料仓的炉顶无料钟装料设备,并于1990年安装在水岛厂3号高炉上。新开发的无料钟装料设备采用优化垂直溜槽形状、直径和控制炉料排出的开始位置的办法,克服了传统的平行无料钟装料设备在炉内圆周方向布料不均的缺点,确立了使用细粒烧结矿达17％的技术。 川崎开发的新型装料系统,供千叶6号高炉大修时采用。在炉料分布方面,从堆积料层的稳定性和料层透气性的观点出发,进行了大量的模型试验和理论评估。 川崎开发了新的炉顶炉料装料设备,由能够多批装料的3个平行料仓、可逆倾斜装料、能使原料下降轨迹垂直和稳定的旋转溜槽组成。这种新型无料钟装料设备具有可控能力好、布料自由度大的特点。在确定理想布料的加料形式的同时,开发和确认了炉料分布模型。 为在大量使用劣质原料时,高炉获得稳定操作,开发了能够定量评估炉料异常下降的指标体系和高炉操作模拟器,并用来降低铁水硅含量。 由于难以直接测量,不能很好地确定高炉炉缸内的状况。不过,通过分析炉缸的温度分布和高炉出铁数据,提出了在高炉底部存在渣铁的"低透过层"的假设。但是,在控制方法方面,还有待进一步研究。 大量喷吹煤粉是未来的必要技术。因此,用试验炉和多个模型研究了煤粉的燃烧性,发现高挥发分、低流动性煤具有较高的燃烧性。而且,开发了一个二维数学模型,可用来评价煤粉的流动性和燃烧性。根据该模型,发现煤粉的燃烧性受喷枪下端形成的紊流支配,据此,开发了强紊流烧嘴。 在炼铁新工艺领域,于1994年在世界上首次商业化应用了2段风口式焦炭充填层熔融还原(STAB)工艺,回收利用不锈钢熔炼粉尘。熔融炉设计金属产能为140t／d,目前已达150～160t／d。还充分利用熔融炉的特点,正在进行回收电炉粉尘中的锌和铁的工艺开发,将于几年后进行商业化应用。另外,川崎还参加了取代高炉的DIOS熔融还原工艺的国家项目,并进行了流动床预还原技术的开发。 徐国群　供稿     

ИССЛЕДОВАНИЕ ВЛИЯНИЯ ОПТСКАНИЯ ШИХТОВЫХ МАТЕРИАЛОВ НА ДВИЖЕНИЕ ГАЗОВОГО ПОТОКА В МОДЕЛИ ДОМЕННОЙ ПЕЧИ

本文的特点是应用了与高炉相似的模型,因而避免了高炉中试验条件很难稳定的困难,取得了较好的结果。文中介绍炉料下降对气流运动的影响。由实验数据可以清楚地看出,炉料下降对气流在料层中分布的影响很小,但却大大地降低气流通过料层的压头捐失(3.5—19％)。压头损失减小的程度取决于料层静止时的阻力。随风量的增加,压头损失减少的绝对值也跟着提高,但减少的百分率不变。改变炉料下降的速度却不影响炉料下降对气流运动影响的关系。文中指出,炉料下降对气流运动影响的主要因素是料层中空隙的体积在炉料下降时得到了增加。     

在高炉模型中研究炉料下降对气流运动的影响

本文的特点是应用了与高炉相似的模型,因而避免了高炉中试验条件很难稳定的困难,取得了较好的结果。文中介绍炉料下降对气流运动的影响。由实验数据可以清楚地看出,炉料下降对气流在料层中分布的影响很小,但却大大地降低气流通过料层的压头捐失(3.5—19%)。压头损失减小的程度取决于料层静止时的阻力。随风量的增加,压头损失减少的绝对值也跟着提高,但减少的百分率不变。改变炉料下降的速度却不影响炉料下降对气流运动影响的关系。文中指出,炉料下降对气流运动影响的主要因素是料层中空隙的体积在炉料下降时得到了增加。     

本钢七号高炉大矿批的研究及应用

七号高炉采取大α角、大矿角布料,在稳定焦批创造稳定的焦炭平台的同时,通过中心加焦保证了中心气流的发展,实行大矿批生产,提高了煤气利用,提高了冶炼强度,降低了燃料比。目前七号高炉的利用系数达到了2.350t/(m3·d),焦比降低到340kg/t,燃料比降低到523kg/t,同时减少设备损耗,降低设备休风率,实现了大矿批生产节耗、增产的目标。     

Coke properties at tuyere level in blast furnace with pulverized coal injection

Coke in the blast furnace experiences great changes in their properties during the blast furnace operation. Pulverized Coal Injection (PCI) into the blast furnace through tuyeres together with oxygen enrichment affect coke properties and blast furnace operation. Using coke sampler at tuyere level, coke samples were collected and analysed at various coal injection rates in the both conventional and co-axial oxygen enrichment. With the help of information obtained from coke sampling experiments, gas permeability resistance index at lower part of blast furnace (LK) and mean size variation of coke were predicted and matched well with the measurements.     

Thoughts on lead blast-furnace smelting

On the basis of limited experimental work conducted at the Port Pirie smelter, it would appear that, by increasing the specific surface of sinter, and possibly that of coke as well, a marked increase in the rate and degree of sinter reduction in the furnace shaft can be achieved. Fusion-point tests have shown that this increased reduction means a much higher sinter fusion point and narrower plastic zone, while the more efficient utilization of coke in the furnace is inherent in the intensification of reduction by the provision of a more reactive sinter surface. Investigations aimed at increasing the ability to operate the blast furnace with a higher lead tenor of sinter reducing fuel cost proportionately, and at eliminating the loss in reduction potential in coke entering the furnace, as shown by the presence of appreciable proportions of CO in the top gases, are reported. Several lines for future investigations that could result in improved smelting methods are proposed.     

Analysis of factors that limit the production rate and coke rate in the iron blast furnace

An engineering analysis indicates that the coke rate in present blast-furnace practice is set not by chemical or thermal needs but to give adequate charge permeability for economical driving rates. An equation showing interrelations among pressure drop, gas flow, and charge characteristics has been derived. Flooding conditions and the location of the fusion zone are discussed. Maximum ore size is probably limited by chemical reducibility rather than by heat transfer.     

MATHEMATICAL MODEL OF BLAST FURNACE BURDENING AND PREDICTION OF ITS COKE SAVING EFFECT

本文采用最优设计理论,研究了低燃料比的高炉配料模型、高炉节焦回归方程和节焦预测计算程序,并由此预示高炉炼铁低燃料比、对应低燃料比的配料方案和供应热风炉的焦炉煤气量,以及高炉煤气达到的风温水平.既能为高炉炼铁选取低燃料比的配料方案提供计算模型,又能用电子计算机预测高炉炼铁的炉料结构编制计算程序.     

Thermodynamic modeling of lead blast furnace

A thermodynamic model was developed to predict the distribution behavior of Cu, Fe, S, O, Pb, Zn,As, and the heat balance in a lead blast furnace. The modeling results are validated by the plant data of a lead smelter in Kazakhstan. The model can be used to predict any set of controllable process parameters such as feed composition, smelting temperature, degree of oxygen enrichment and volume of oxygen-enriched air. The effects of the blast air, industrial oxygen, and coke charge on the distribution of Cu, Fe, S, O, Ph, Zn, As, the heat balance, and the lead loss in slag, were presented and discussed.     

The Limits of Modern Blast Furnaces

The limitations of expanding blast furnace capacity are discussed. These limitations are: the time required for reduction of oxides in ore or sinter, heat transfer from gas to solids, fluidization of the charge at the stockline, and hearth capacity. As a solution for increasing capacity, it is suggested that rich, basic, reducible sinter should be hot-charged into the furnace, and that top pressures should be sufficiently high to prevent fluidization of the charge. In order to limit top pressures to a reasonable level, it is suggested that large, oval-shaped, low-shaft blast furnaces be used. The design features of such furnaces are presented. Calculations of production rates for circular- and oval-shaped furnaces of equal working volume are compared.     

A Complete Pretreatment of Blast Furnace Burden at an Integrated Steel Works

As indicated above, we, at the Chiba Works, classify and blend various materials in a rationalized system, so as to produce the most suitable blast furnace burden. Table VIII shows an outline of the equipment and Table IX the performance result.With special reference to No. 1 blast furnace, it has been giving as high a yield as 4.5 net tons per sq ft of the hearth area, without using any special techniques such as high top pressure operation.As for No. 5 blast furnace, which has the world’s largest inner volume, it was blown-in in March this year and has been in an uprating operation with an excellent performance. During the month of July, it marked a yield of 3470 net tons per day.These achievements, we believe, are largely due to our intensified pretreatment system, under which economically obtained iron ore of all kinds of size are so treated as to be used most efficiently at the blast furnace, sintering plant, and pelletizing plant.No less important to this success is the use of bedding system which makes it possible that iron-bearing waste or residue materials generated in small lots from various stages of iron and steelmaking operations at the Chiba Works are turned into large uniformed lots for complete recovery.     

A STUDY ON THE BEHAVIOUR OF GALLIUM IN THE IRONMAKING PROCESS

Gallium is a valuable rare metal which is mainly being used in the production of GaAs. The demand for gallium is increasing but production is limited since gallium is extracted only as a by-product of bauxite processing. On the other hand coal, ironmaking coke and iron ore gangue contain traces of gallium. However little is known about the behaviour of gallium in ironmaking. The aim of the study is to clarify the distribution of gallium between hot metal, slag and top gas by means of laboratory experiments. It was found that Ga2O3 is not stable in blast furnace slags and that gallium is retained in hot metal. Vacuum distillation experiments with hot metal showed that gallium is not transferred to the gas phase. Data on the input and output of gallium at two industrial blast furnaces, as well as chemical analyses of the gallium content of several cokes are presented, too.     

A STYDT ON THE BEHAVIOUR OF GALLIUM IN THE IRONMAKING PROCESS

Gallium is a valuabie rare metal which is mainly being used in the production of GaAs,The demand for gallium is increasing but production is limited since gallium is ex-tracted only as a by-product of bauxite processing.On the other hand cool,ironmaking coke and iron ore gangue contain traces of gallium.However little is kmown about the behaviour of gallium in ironmaking.The aim of the study is to clarify the distribution of gallium between hot metal,slag and top gas by means of laboratory experiments.It was found that Ga2O3 is not stable in blast furnace slags and that gallium is retained in hot metal.Vacuum distillation experiments with hot metal showed that gallium is not transferred to thw gas phase.Data on the input and output of gallium ot two industrial blast furnaces,as well as chemical analyese of the gallium content of several cokes are presented,too.