*This is an abstract only. No full paper is available for
The last decade was a turbulent time for the steel industry. The re-organisation of the steel industry progressed across national borders, while the world’s steel demand expanded rapidly and reached over 1.6 billion tonnes per annum. Japan depends on imports of iron ore for steel production and 60 per cent of this is sourced from Australia. The increased demand resulted in soaring prices for raw material such as iron ore and metallurgical coal. Although Japan’s steel industry has achieved world-class energy efficiency, we are still required to improve further to contribute to a low carbon society and combat global warming.
Nippon Steel and Sumitomo Metal Corporation (NSSMC) was established in 2012 by merging two companies. After Nisshin Steel joined members of the NSSMC Group in 2017, the group ranked as the third largest steelmaking company in the world. The combined NSSMC Group has reduced its total number of blast furnaces, while enlarging the inner volumes of individual blast furnaces to enhance its production efficiency. Currently, we have 16 sintering machines, one of which has the world’s largest production capacity with a sintering area of 700 square metres, to support 15 blast furnaces at eight works in Japan. Seven of the blast furnaces have been enlarged to have an inner volume above 5000 cubic metres. As we have enhanced our production efficiency, we require high quality sinter and coke to maintain stable and effective blast furnace operation. The prices of raw materials have increased drastically due to the strong demand for steel; nevertheless, the quality of iron ore and coal has deteriorated. Therefore we need to develop new ironmaking technologies to meet the challenge of sustainability of production with low-grade raw materials. These technologies include intensified granulation, designed structure of the ore bed and fuel combustion control in sintering, and burden distribution control and visualisation in the blast furnace. This review provides a summary of the development of ironmaking technologies in Japan for utilisation of low-grade raw materials, along with productivity enhancement, measures for energy conservation, and reduction of CO2 and NOx emissions.
Araki, K, Kamijo, C and Higuchi,
K, 2017. Recent progress of ironmaking technologies in Japan, in Proceedings
Iron Ore 2017, pp 3–4 (The Australasian Institute of Mining and Metallurgy: