ASSESSMENT OF REDUCTION BEHAVIOR OF HEMATITE IRON ORE PELLETS IN COAL FINES FOR APPLICATION IN SPONGE IRONMAKING

Studies on isothermal reduction kinetics (with F grade coal) in fired pellets of hematite iron ores, procured from four different mines of Orissa, were carried out in the temperature range of 850–1000°C to provide information for the Indian sponge iron plants. The rate of reduction in all the fired iron ore pellets increased markedly with a rise of temperature up to 950°C, and thereafter it decreased at 1000°C. The rate was more intense in the first 30 minutes. All iron ores exhibited almost complete reduction in their pellets at temperatures of 900 and 950°C in < 2 hours' heating time duration, and the final product morphologies consisted of prominent cracks. The kinetic model equation 1 ? (1 ? α)^1/3 = kt was found to fit best to the experimental data, and the values of apparent activation energy were evaluated. Reductions of D. R. Pattnaik and M. G. Mohanty iron ore pellets were characterized by higher activation energies (183 and 150 kJ mol^?1), indicating carbon gasification reaction to be the rate-controlling step. The results established lower values of activation energy (83 and 84 kJ mol^?1) for the reduction of G. M. OMC Ltd. and Sakaruddin iron ore pellets, proposing their overall rates to be controlled by indirect reduction reactions.     

铁矿石还原过程速率探讨

本文定义了还原反应速率的计算式，依据矿石失重实验数据可计算反应速率的大小及其变化关系，可分析矿石还原过程速率的限制性环节。     

铁帽型含金复合矿煤基直接还原过程中铁氧化物的行为

对铁帽型含金复合矿煤整直接还原过程中铁氧化物行为进行了研究，并用粉晶X-射线衍射对其反应机理进行验证。结果表明：直接还原过程中，不仅包括铁氧化物的还原相变，同时还存在铁氧化物同其它氧化物之间的固相反应。     

利用普通品位铁矿的煤基直接还原新工艺研究

根据转底炉工艺高温快速还原的特点,在实验室模拟生产条件,进行了以普通品位铁矿为基础的直接还原试验,得到了在该工艺条件下的金属化球团、粒天珠铁、精选铁粉等高金属化率产品,并对其性能及后续处理做了相应的研究和探讨,提出了普通铁矿先还原、后分离（磁分、熔分、筛分）的直接还原炼铁新工艺路线,认为转底炉直接还原及后分离工艺是技术上和经济上都适于处理普通品位铁精矿和难选赤矿的一条新途径。     

国内外钢铁制造业节能减排的研究与应用

阐述了钢铁制造业节能减排的意义.比较全面地介绍了国内外在铁系统、钢系统节能减排的现状和研究与发展的趋势,并根据中国的国情,为进一步推进节能减排提出了一些建议.     

哈默斯利铁矿石在首钢炼铁生产的应用

介绍了两种哈默斯利块矿及其混合矿的性能，分析了它们在首钢高炉的应用情况，分析了哈默斯利粉矿在烧结生产中的应用情况。     

STUDIES ON THE REDUCTION KINETICS OF HEMATITE IRON ORE PELLETS WITH NONCOKING COALS FOR SPONGE IRON PLANTS

In the present investigation, fired pellets were made by mixing hematite iron ore fines of ?100, ?16 + 18, and ?8 + 10 mesh size in different ratios and studies on their reduction kinetics in Lakhanpur, Orient OC-2 and Belpahar coals were carried out at temperatures ranging from 850°C to 1000°C with a view toward promoting the massive utilization of fines in ironmaking. The rate of reduction in all the fired iron ore pellets increased markedly with an increase in temperature up to 1000°C, and it was more intense in the first 30 min. The values of activation energy, calculated from integral and differential approaches, for the reduction of fired pellets (prepared from iron ore fines of ?100 mesh size) in coals were found to be in the range 131–148 and 130–181 kJ mol^?1 (for α = 0.2 to 0.8), indicating the process is controlled by a carbon gasification reaction. The addition of selected larger size particles in the matrix of ?100 mesh size fines up to the extent studied decreased the activation energy and slightly increased the reduction rates of resultant fired pellets. In comparison to coal, the reduction of fired pellets in char was characterized by significantly lower reduction rates and higher activation energy.     

高炉配加经济矿料生产实践

经济矿料通常由褐铁矿或半褐铁矿组成,含铁品位低、杂质多,在烧结中配加它是钢铁行业应对资源危机、降低生产成本的有效措施之一。安钢通过生产试验与理论探索,烧结经济矿料的使用量占到了铁矿粉消耗总量的50.1%,成本下降10%左右,完全适应了大配比经济矿料烧结生产。同时,高炉操作为适应低品位经济矿料采取了各种措施,实现了较好的技术经济指标。     

改性铁及海棉铁中金属铁的分析

本文阐述了改性铁、海棉铁中MFe（金属铁）的分析,通过试验,总结出用FeCl3溶解MFe,重铬酸钾测定的方法要点,以及干忧因素的消除和分析方法比较。     

铁浴中铁氧化物还原的基础研究进展

本文总结了多年来铁浴中铁氧化物还原的研究结果。着重介绍了纯氧化铁和熔渣中氧化铁被铁浴中[C]还原的研究情况,为今后铁浴式熔融还原工艺的开发和基础理论的进一步研究提供了一些有价值的信息。     

海绵铁生产与钢铁工业短流程

在实施能大幅度节约能源的钢铁工业短流程中，海绵铁的生产是薄弱环节。介绍了目前海绵铁生产的现状和存在问题，结合美国Ｆａｓｔｍｅｔ和Ｉｎｍｅｔｃｏ法的特点探讨了海绵铁生产的应走的道路，认为用敞焰加热快速原含碳团矿生产海绵铁是一种简单，经济，实用的方法。     

铁矿／煤混合料中碳的还原过程研究

在铁矿／煤混合料中，在借助气体的直接还原开始前，确实存在着碳直接还原铁氧出物的固体间的直接还原，但不能达到有效的反应速度。只有当温度达到碳的气化反应温度，借助气体的直接还原开始后，还原过程才能开始激烈进行。     

低品位铁矿石直接还原新工艺研究

对多种难选铁矿石进行了煤基直接还原和渣铁分离研究，提出了煤基直接还原──渣铁分离──还原铁粉冷固结成型的新的工艺流程。所得产品的铁品位、金属化率和铁回收率分别在９０％、９２％和８４％以上。直接还原铁粉经冷固结成型后即为电炉炼钢的优质原料。该工艺为利用我国大量尚未开发的低品位难选铁矿石提供了新的途径。     

高磷铁矿脱磷工艺研究现状

我国铁矿资源长期紧缺已是不争的事实,合理开发利用鄂西巨型铁矿资源具有重大经济意义,对此本文论述了国内外高磷铁矿降磷的现状及其发展,总结了当前降磷存在的问题,着重阐述了选矿降磷工艺和铁水预处理脱磷工艺研究的现状及其相关设备和材质的研究现状.     

铁矿-煤球团和空气在并流条件下的还原实验研究

在管式电炉内,进行了铁矿－煤球团和空气在并流条件下还原实验研究。结果表明：铁矿－煤球团能够被还原并获得较高的金属化率,还原后的球团被再氧化先是脱碳反应抑制了金属化率的进一步升高,然后是金属铁的氧化使金属化率降低。     

SYP增效剂用于褐铁矿烧结的试验研究

根据昆钢红河钢铁有限公司烧结以褐铁矿为主的原料特点,结合生产实践提出了添加SYP增效剂烧结的技术思路。在实验室烧结杯试验取得初步效果的基础上,组织了工业性试验,验证了SYP增效剂改善烧结生产技术经济指标的作用。SYP增效剂的使用,在一定程度上解决了褐铁矿烧结强度差、返矿量大的问题,为拓宽资源利用,降低成本奠定了良好的基础。     

节能减排集结号下钢铁工业环境工作思考

环境问题正在日益受到全世界的关注,针对环境问题提出的节能减排任务也是非常紧迫的。钢铁工业作为减排工作的重点对象之一,应大力推进节能减排技术,打好这场攻坚战。     

PROPERTIES AND FEATURES OF DIRECT REDUCED IRON

The blast furnace process is still the predominant method for primary iron production. However, the disadvantages inherent to the process led to the development of alternative processes such as the mini blast furnace process, smelting reduction process, and direct reduction process. Many of these alternative processes are still under development. However, direct reduction processes have reached some level of commercial applicability and are considered to be the most developed alternative ironmaking route. It is coke-less and environmentally friendlier when compared to the blast furnace process. In addition, direct reduced iron has a well-defined chemical composition when compared with steel scrap and has efficient melting properties in the electric arc furnace. Consequently, there is a great increase in the demand for direct reduced iron in electric arc steel making. These attractive features have led to an increase in worldwide production of direct reduced iron, which is currently approaching 50 million tons. Thus, direct reduced iron is gaining more importance. Hence, this article summarizes the basic properties and features of direct reduced iron.     

钢铁产业节能减排的科技支撑机制分析

本文分析了我国钢铁产业节能减排的宏观形势,从铁矿石资源、钢铁冶炼行业、钢铁产品三个方面可以看出科技支撑节能减排的空间较大,通过三个维度探讨了我国钢铁产业节能减排的科技支撑机制。     

喀左海绵铁冶炼厂工厂设计若干特点初析

本文介绍了喀左“一步法”直接还原工艺海绵铁厂的设计特点以及在设计和试生产中所取得的经验。