Direct Iron Ore Smelting Process for Ironmaking Mar28

Direct Iron Ore Smelting Process for Ironmaking...

Direct Iron Ore Smelting Process for Ironmaking Direct iron ore smelting (DIOS) process is a smelting reduction process for the production of hot metal (liquid iron). It is a two-stage process which has been developed in Japan. It uses non-coking coal in a powder or granular form to smelt iron ore fines into liquid iron (hot metal) and hence, there is no necessity of a coke ovens plant and a sintering plant. The ore fines are pre-reduced in a fluidized bed furnace and are charged in the smelting reduction furnace along with non-coking coal and fluxes. Oxygen is blown into the smelting reduction furnace. The two stages of the DIOS process consists of (i) pre reduction of iron ore in preliminary reduction furnace (PRF), and (ii) the final reduction and melting in the smelting reduction furnace (SRF). The pre reduction of the ore is carried out in two steps utilizing the exhaust gas from the SRF. Each of the steps uses a fluidized bed reactor which is designed as a vertical furnace. The development of the DIOS process started in 1988 in Japan as a joint research project among eight iron manufacturing companies who had, prior to 1988, been studying the smelting-reduction process individually. This project was sponsored by MITI, the Japanese Ministry of International Trade and Industry. Japanese companies and Japan Iron and Steel Federation (JISF) actively supported the development of the process during the period of 1988 to 1996. Core technology study necessary for the construction of the pilot plant was done during the period 1988 to 1990. During this period core technologies were established. These core technologies include (i) an increase in the thermal efficiency of a SRF, (ii) the technology to be integrated with a PRF, (iii) the technology for...