Turbocompressor for blast furnaces

Increases in the useful volume and rates of operation of blast furnaces are causing a tightening of requirements on blast pressure and the amount of blast that is used. Accordingly, higher standards are also now being set for the efficiency and reliability of turbocompressors, as well as their ability to be integrated into furnace automation systems. The Mi-Fi-Bu Company can satisfy bulk orders for 5000-m³/min turbocompressors driven by stationary 24-MW steam turbines. The company designs, builds, delivers, and installs the equipment, places it into operation, and provides training for its operators. __________ Translated from Metallurg, No. 7, pp. 57–58, July, 2006.     

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.     

Improved iron-ore pellets for blast furnaces

A production technology for iron-ore materials with improved metallurgical characteristics is developed and tested. The following materials are considered: fluxed pellets containing residual carbon; fluxed local agglomerates from concentrates with a wide range of silica content; local agglomerates with an elevated iron content; local agglomerates with residual carbon; and local agglomerates with both elevated iron content and residual carbon.     

A new charging protocol for blast furnaces

After tests at OAO Chelyabinskii Metallurgicheskii Kombinat, a new protocol has been introduced for blast-furnace charging. The proposed cycle consists of several mixed deliveries (ore + coke) and finally the delivery of several charging ladles with a single type of coke. This protocol has now been introduced at all three blast furnaces, with decrease in coke consumption and increase in furnace productivity.     

大型高炉炉前作业的生产组织

从太钢5号高炉4年多的生产实践出发,总结提出炉前作业应遵循的一些基本原则和采取的措施,认为良好的炉前作业对大型高炉维持生产顺利进行,保持煤气流和热负荷稳定及炉缸活跃有重要作用。     

Metal structures of blast furnaces

This article describes several types of support systems for the load-bearing structures of blast furnaces and their auxiliary equipment. A detailed discussion is presented of systems of the Czechoslovakian type. The lower part of such systems consists of a three-dimensional framework resting on four columns having a certain modulus. Supporting beams are located at the level of the casting platform and are suspended from other beams installed above the bustle pipe. One important advantage of this furnace design is that the combined weight of the auxiliary equipment and the load-bearing structures is divided between the four-column system and the furnace proper. This is convenient from a static viewpoint and significantly reduces the loads on the structure. One advantage of the proposed type of load-bearing system is that the weight of the furnace and the auxiliary equipment is evenly distributed over the entire area of the foundation slab. The proposed system can be used on all types of furnaces. Another advantage of the Czech system is that it affords safe access to the equipment located in the bottom part of the furnace. During the reconstruction of blast furnaces, the upper part of the furnace can be suspended on the four-column system while the bottom of the furnace is being replaced. __________ Translated from Metallurg, No. 7, pp. 54–56, July, 2006.     

Gas behavior in blast furnaces

The productivity and energy consumption of blast furnaces may be significantly improved by modifying the gas distribution in the hearth—specifically, by increasing the total cross section of the air tuyeres and reducing the gas pressure in the furnace’s working space.