SS Manufacture - Indian Practice and Electrical Perspective

摘要

The major route for SS production has been via EAF. The challenge of decarburising the melt with oxygen in the presence of high levels of chromium has been handled through AOD and VOD processes. In plants manufacturing other alloys as well as SS, high carbon liquid steel is produced in the EAF, without any chromium addition. All Chrome addition takes place in the AOD, increasing the process time, cost, temperature and refractory wear. EAF has high oxygen consumption and foaming arc allowing long arcs. In SS plants, the EAF charge consists of SS/MS scrap high C ferrochrome. Minimal oxygen is used and 85% of energy is electrical. Foaming slag practice has not been successful till now. Short arc lengths are used. Proper choice of Electrode Regulation System and Smart Furnace Melt program are essential. Modern Electrode Regulators are similar in regulation speeds. Hence the choice must be based on the diagnostic and analytic features and other special features which can eliminate VCB trippings and Electrode breakages. Improvements can be achieved in some areas. Electromagnetic Stirring will help in reducing arcing time, lining wear and allow longer arcs. Possibilities of modifications to the shell to allow foaming slag practice should be explored. Waste heat recovery using high temperature quenching and evaporative cooling to generate steam can be adapted.