著者

内藤 誠章 武田 幹治 松井 良行

出版者

一般社団法人 日本鉄鋼協会

雑誌

鉄と鋼 (ISSN:00211575)

巻号頁・発行日

vol.100, no.1, pp.2-30, 2014 (Released:2013-12-31)

参考文献数

218

被引用文献数

9 14

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The modern blast furnace operation at integrated steel works in Japan has started in 1901 by the first blown-in of Higashida No. 1 blast furnace in Yawata Works, while a 150 years history of Japanese steel industry has dated back to the first western blast furnace built by T. Ohashi in 1857. The steel industry has been supporting the Japanese economy as a key industry which supplies base materials for social infrastructure and developments throughout the pre and post war periods.After the recovery period from the war destruction, Chiba Works of Kawasaki Steel Corp., were built and started its operation in 1953 as the first integrated steel works in Keiyo Industrial Region after the war. During the rapid growth period, many coastal steel works equipped with a large blast furnace more than 3000m3 and some of 5000m3 were built for the efficient marine transportation of raw materials and steel products. Most advanced technologies, high pressure equipment, stave cooler system and bell-less charging system etc., were introduced, improved and has risen to the top level in the world with low reducing agent ratio (RAR), energy saving and long service life of a blast furnace and coke ovens.Energy shift from oil to coal by the oil crisis, cost oriented operation design and technology were tackled and the hot metal of about 80 million tons is manufactured with 27 blast furnaces including over 5000m3 large scale blast furnaces in 2012. During this period, our industry has faced many economical and social pressures of high exchange rate of yen, oligopoly of mining market, global warming problem, and surge of iron ore and coal prices by the rapid growth of the BRICs. We have kept our competitive positions by developing advanced technologies on pulverized coal injection, extended use of low cost iron resources, recycling for environment and CO2 mitigation technologies.Prospects of ironmaking technologies for other decades are discussed by reviewing various papers published and looking back the history of ironmaking developments during the last 100 years.

著者

大山 伸幸 岩見 友司 山本 哲也 町田 智 樋口 隆英 佐藤 秀明 佐藤 道貴 武田 幹治 渡辺 芳典 清水 正賢 西岡 浩樹

出版者

一般社団法人 日本鉄鋼協会

雑誌

鉄と鋼 (ISSN:00211575)

巻号頁・発行日

vol.97, no.10, pp.510-518, 2011-10-01 (Released:2011-10-01)

参考文献数

42

被引用文献数

3 8

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JFE Steel Corporation developed the hydrogen-based gas fuel injection technology for sintering machines to improve sinter quality without increasing coke breeze ratio. With the technology, it is possible to extend the temperature zone between 1200°C and 1400°C by injecting the gaseous fuel from the top surface of the sintering machine as a partial substitute for coke breeze. Theoretical and experimental studies were carried out to verify the effect of the gaseous-fuel injection technology on pore structure in the sinter cake with the X-ray CT scanner and sintering pot test.It is important to hold the temperature between 1200°C and 1400°C in order to produce high strength and high reducibility sinter. The liquid phase ratio can be increased with extending the proper temperature zone by applying the gaseous fuel injection technology. The increase in liquid phase ratio promotes the combination of pores (1–5 mm) and sinter strength is improved. At the same time, the pores over 5 mm growth are promoted and the permeability is improved in the sintering bed. Moreover, the low-temperature sintering process depresses the iron ore self-densification. Micro pores under 1 μm remain in unmelted ores and improve sinter reducibility. As a result, the technology enables to improve the pore structure in the sinter cake and sinter quality.The technology was put into commercial operation at Keihin No. 1 sinter plant in January 2009 and stable operation has continued up to the present. As a result, the energy efficiency in the sintering process is greatly improved, and it has been achieved to reduce CO2 emissions by a maximum of approximately 60000 t/year at Keihin No. 1 sinter plant.