Submerged Arc Furnace, an Alternative for Smelting of Sponge Iron?

Abstract

The paper describes the pattern of the conventional submerged are pig iron furnace and the influence and consequences of introducing preheated and prereduced charge. The features of the ELKEM prereduction process are presented and the theoretical philosophy of the process as compared to other direct reduction processes is discussed. It is found of importance that prereduction in rotary kiln is not carried so far as to create problems due to agglom-eration and ring-formation of the feed, the last port of the reduction can more favourably be completed in the electric furnace. Experience and operating results fronz installations at Highveld and Skopje are reported. Form-ation of fines in the kiln and accumulation of fines in the electric furnace have proven to be major obstacles. The paper emphasizes consequently the importance of mater-ial strength and advocates the use of sintered pellets. A simple shaft sintering equipment of E Mem Spigerverket design is presented. On basis of experience from smelting of FeNi from calc-ined, hot fed oxide ores in submerged arc furnaces and some preliminary smelting tests in Elketn—Spigerverket al s' Research Center at Kristiansand, Nonvay, the paper proposes submerged arc smelting technics for smelting of sponge iron to crude steel as an alternative to open arc furnaces to use (semi-steel) in a continuous process. Pilot tests indicate that the chemistry could be easily controlled, procedures and design for industrial install-ation will have to be developed.