Automatic system for predicting the viscoplastic region in a blast furnace

A mathematical model to describe the region of the blast furnace in which the charge materials are in the viscoplastic state (VPR) has been constructed for a blast furnace at the West Siberian Metallurgical Combine. The furnace has a standard bell-and-hopper charging apparatus and movable top slabs. The results of studies that were conducted led to the development of an automated system to monitor the VPR in blast furnaces. The system allows furnace operators to form the required VPR profile in accordance with current objectives. It also allows them to make real-time determinations of the reasons for changes in the gas flow inside the furnace, that flow being affected mainly by the internal profile of the furnace and the location of the VPR. Ultimately, use of the system allows the operators to promptly take action to keep the charge distribution and gas flow optimum. __________ Translated from Metallurg, No. 2, pp. 32–34, February, 2006.     

Aspects of the control of charge distribution in a blast furnace with additional regulators

The development and introduction of a charging apparatus with a rotary distributor required additional study of the distribution of the charge materials in the top of the furnace and optimization of the charging regimes to ensure efficient, high-productivity operation of the blast furnace. Studies and previous blast-furnace operation at the West Siberian Metallurgical Combine have shown that a rotary distributor efficiently distributes the charge materials and the ore burden over the radius of the top of the furnace when the charging sequence is composed of a systematically repeating combination of rounds of ore-bearing materials and coke charged onto the surface of the stock in a certain order along certain trajectories. Smooth (auxiliary) control of the radial distribution of the ore-bearing materials and coke is accomplished by changing the thicknesses of the layers of these two charge components in different annular zones of equal size, as well as by shaping the initial stockline in such a way as to keep the ore-bearing materials from moving over the surface of the stock and falling into the peripheral zone of the top of the furnace.     

Charging apparatus with a revolving distributor: Five years of successful operation on blast furnace No. 3 at the Bhilai Metallurgical Plant

A rotary charging apparatus (RCA) has been in use on 1033-m³ at the Bhilai Metallurgical Plant (in India) since 1998. The RCA is a new type of charging apparatus in which the main working element is a five-vane revolving charge distributor that provides for multi-flow, multi-layered distribution of the charge materials in the top of the furnace. The revolving distributor makes it possible to flexibly and efficiently regulate the distribution of the materials over the entire radius of the top by changing the speed and direction of rotation of the rotor. The operational and design features of the RCA ensure a higher quality distribution of the materials in the top, which in turn leads to a significant savings of coke and an increase in furnace productivity. The total cost of maintaining and repairing the RCA is proving to be substantially lower than the corresponding costs for standard double-bell-and-hopper and chute-type charging apparatuses. The investment in the RCA is recovered in six months or less.     

Blast-furnace operation with coke fines

Conclusion Depending on the smelting conditions, the use of coke fines (36-25 mm) for up to 22% of the coke charged into a blast furnace having a standard bell-and-hopper charging appratus, led to a decrease in pig-iron output by 1.0–1.6% (or 0.2–0.4% for each 1% of coke fines), an increase in unit coke consumption by 0.8–1.0% (or by 1.0%-0.19-0.17%), and a deterioration in the drainage capacity of the hearth. The performance indices of the furnace equipped with a revolving distributor show that it is possible to force smelting while using up to 25% coke of the 36-25-mm fraction in the charge. If the coke in the charge consists of more than 30% fines, smelting rate decreases and hearth performance declines. These developments are accompanied by a 3.3–3.6% reduction in furnace productivity (0.12–0.13% for each 1.0% of the 36-25-mm fraction of coke) and a 0.85–0.90% increase in unit coke consumption (0.03–0.04% for each 1% of coke fines). West Siberian Metallurgical Combine. Translated from Metallurg, No. 1, pp. 38–39, January, 1999.     

Charging technology for modern electric-arc furnaces

Conclusion  Electric steelmaking is assuming an increasingly larger role in steel production, with the use of larger quantities of scrap substitutes and scrap of different levels of quality. Thus, the goal is to improve the economic and technical indices of the furnaces, despite the difficulties and limitations connected with the use of this new type of charge. In improving charging and melting operations and furnace equipment, certain basic requirements must be met:

Study of Pellets and Lumps as Raw Materials in Silicon Production from Quartz and Silicon Carbide

The use of high-purity carbon and quartz raw materials reduces the need for comprehensive refining steps after the silicon has been produced carbothermically in the electric reduction furnace. The current work aims at comparing the reaction mechanisms and kinetics occurring in the inner part of the reduction furnace when pellets or lumpy charge is used, as well as the effect of the raw material mix. Laboratory-scale carbothermic reduction experiments have been carried out in an induction furnace. High-purity silicon carbide and two different high-purity hydrothermal quartzes were charged as raw materials at different molar ratios. The charge was in the form of lumps (size, 2–5 mm) or as powder (size, 10–20 μm), mixed and agglomerated as pellets (size, 1–3 mm) and reacted at 2273 K (2000 °C). The thermal properties of the quartzes were measured also by heating a small piece of quartz in CO atmosphere. The investigated quartzes have different reactivity in reducing atmosphere. The carbothermal reduction experiments show differences in the reacted charge between pellets and lumps as charge material. Solid–gas reactions take place from the inside of the pellets porosity, whereas reactions in lumps occur topochemically. Silicon in pellets is produced mainly in the rim zone. Larger volumes of silicon have been found when using lumpy charge. More SiO is produced when using pellets than for lumpy SiO₂ for the same molar ratio and heating conditions. The two SiC polytypes used in the carbothermal reduction experiments as carbon reductants presented different reactivity.     

Improving the batch distribution at OAO NLMK blast furnace 6

The charging programs for a blast furnace with a nonconical charging system are investigated. On that basis, rational charging conditions are developed and tested. Experimental experience indicates more economical furnace operation, on account of the improved batch distribution over the charge hole and the reduced heat losses through the cooling systems.     

Briquets for washing blast furnaces

Periodic washing of the hearth of a blast furnace by charging hard-to-reduce iron-bearing materials helps form fluid iron-bearing slags whose iron is reduced mainly by coke fines in the coke column. Lump iron ore, specially prepared washing sinters, or welding slag are usually used for this purpose. The washing sinter contains up to 50% ferrous oxide. One alternative to the washing sinter might be briquets made from mill scale. Washing briquets made from mill scale with a cement binder (8–10% Portland cement M500) are made by vibrational compaction. These briquets have good cold strength, remain intact when heated in a reducing atmosphere to 1200°C at a rate of 500°C/h (which corresponds to the rate of heating of the blast-furnace charge), and have low reducibility. Inside the fusion zone, they form primary slags based on iron-calcium olivines with an FeO content on the order of 50%. __________ Translated from Metallurg, No. 5, pp. 46–50, May, 2007.     

16.5MVA电炉加料系统的改进

针对大型铁合金电炉加料系统在高温环境和庞大矿物流量的工况下，碳钢料管加速氧化剥落和磨料磨损，采用厚壁不锈钢料管，设计了能够长期无故障运行的新加料系统。     

安钢3#高炉大料批分装生产实践

介绍了安钢为提高煤气利用率和增产节焦,对其3#高炉进行了大料批分装操作试验.通过采取优化炉料结构,控制入炉料粉末,搞好上下部调剂,控制炉体冷却强度等措施,经过8个月的大料批分装生产实践,增产节焦效果明显,各项技术经济指标得到了进一步优化.     

酒钢2500m~3高炉操作制度探讨

结合2011年4～9月酒钢7#高炉经济技术指标,分析探讨了热制度、造渣制度、送风制度以及装料制度中合理操作参数的确定过程,提出了在目前酒钢原燃料条件下,铁水含硅控制在0.50%;炉渣碱度在1.07倍下限波动;进风面积在0.362～0.366m2;批重55～60 t;布料角度不超过39°,档位角差2°,矿角差8°;重视低料线的优化操作思路。实施后,7#高炉基本实现了稳定顺行,各项经济技术指标逐步优化,操作制度更加合理。     

Operation of sintering machines with a one-layer bed

Results are presented from commercial trials performed to examine the effect of the properties of the charge and the parameters of the charging equipment on the formation of the bed during the charging of sintering machines. To simultaneously increase the degree of segregation of the charge and alleviate its over-compaction during the charging operation, it will be necessary to improve the design of the charging system and search for new technical solutions to obtain the necessary charging parameters. __________ Translated from Metallurg, No. 6, pp. 33–37, June, 2006.     

2000m~3高炉降低燃料比实践

针对在原燃料质量不断下降的情况下,如何保持高炉炉况顺行,降低生产成本,取得较好的经济技术指标,提升企业竞争力的现实,唐钢2#高炉通过采取扩大风口面积、增加风量等手段优化鼓风动能,同时对炉顶布料进行了探讨,采用适宜的装料制度,以保持炉缸活跃。     

淮钢5^#高炉上料系统料仓除尘改造探讨

介绍了淮钢特钢有限公司5^#高炉上料系统料仓除尘的改造方案。在不增加风量的前提下,解决了槽上料仓上料扬尘问题,改善了工人的工作环境,确保了生产稳定。     

实用新型热轧钢管连铸圆坯热装系统介绍

实用新型热轧钢管连铸圆坯热装系统取得国家专利。该系统要点是炼钢、连铸系统和轧管机系统集成为一体,1对1匹配,以轧管机产能为基准组织生产;步进式预热炉和高温炉以及回转热锯机,对连铸圆坯加热和锯定尺;生产过程计算机和生产管理计算机控制系统;总图布置紧凑,物流畅通。热装比可达75%～80%,热装温度可达650～800℃;节能减排、降低投资、提高金属收得率等效果。     

基于DEM的无钟高炉布料料流轨迹研究

摘要：离散单元仿真技术被广泛用于研究高炉布料过程中炉料运动的规律,其计算散料运动的方法得到了国内外专家的认可。利用SOLIDWORKS和EDEM的Geometry建立无钟炉顶高炉几何模型,基于DEM结合炉料物理参数进行数学模拟,研究了溜槽倾角、料线深度和溜槽结构对料流轨迹的影响。结果表明：焦炭落点半径随溜槽倾角的增大而增大,倾角为13.3°时,炉料在下落过程中不与溜槽接触;随着料线深度的增大,焦炭的落点半径随之增大,但增量减小;在相同倾角下,矩形溜槽布焦炭时的落点半径比半圆形溜槽的小0.3m,且料流更集中,布料效果略优;有衬板溜槽比光面溜槽布焦炭时的落点半径小0.13m,料流宽度也较小,且能通过料与料之间的摩擦降低炉料对溜槽表面的磨损。     

电炉废钢配料系统升级改造

通过对珠江钢铁有限责任公司原废钢配料系统存在的缺陷的分析,找出改进系统的方法。使用了国产化技术,实现了物料名称的远程传输和中文显示,使配料软件系统更加人性化,减少了人为误操作,改变了系统和外围设备的通信方式,加快了配料的速度,使电炉废钢配料系统在稳定性、快速性、灵活性三个方面得到提高。     

庚辰钢铁230m^3高炉紧急停炉操作实践

2010年11月2日济南庚辰钢铁有限公司230m^3高炉上料系统发生严重故障,预计停止供料10天,采取了紧急打水降料线停炉措施。因停炉是上料系统故障、不能上料引起,此时炉料负荷较重,故在停炉过程中打破了计划停炉的一些常规做法,做到了安全顺利停炉,且全部产品质量合格稳定,取得了较好效果。     

八钢高炉无料钟炉顶的装料制度

以八钢高炉炼铁实践为依据，系统研究和分析了八钢2号和3号高炉炉顶设备装料制度对高炉冶炼的影响。认为高炉操作制度是当前高炉炼铁的主要技术之一，也是影响高炉焦比主要技术经济指标的重要因素。在原燃料和装备水平一定的条件下，合理的操作制度对高炉的技术经济指标起到决定性的作用。     

大型平行式三内胆高真空热处理炉的改造

企业原有的大型平行式三内胆式真空热处理炉在真空度和全炉体温度均匀性两方面已经不能满足新型核燃料组件包壳材料——M5锆合金的热处理工艺要求。该文就大型热处理炉结构的优化、新材料选用、电气控制系统合理配置、真空系统改造和装料舱升级等方面所做的改造进行了阐述。改造后的大型高真空热处理炉能满足M5锆合金特殊热处理工艺的要求。