Abstract
The Japanese traditional ironmaking "Tatara" was the unique process using iron sand and charcoal in the world. In the middle of Meiji period, Mr. Fuyukiti Obana and Mr. Masateru Kuroda improved the Tatara furnace and constructed "Kakuro" and "Maruro" furnaces to use waste slag for refining of pig iron and/or iron sand as iron resources. Tatara furnace was a box type furnace with 1.2 m in height and reconstructed every operation. The Kakuro furnace was raised about 3 m in height using firebricks to improve the productivity. The Maruro furnace was resemble to a charcoal blast furnace. The Tatara had a fayalite slag including about 60% FeO and about 10% TiO2 and the slag for Kakuro had a few percentages of FeO and about 25% of TiO2 using lime with less basicity of CaO/SiO2 than 1. The component of TiO2 in these slags acts as a flux. The quality of steel made from pig iron produced by "Tatara", "Kakuro" and "Maruro" was excellent in comparison with imported steels. The steel was used as a special steel for roll and blade.
