Refractory Use and Wear in Electric Arc Furnaces (EAF)

摘要

The electric arc furnace (EAF) steelmaking process was developed with emphasis on the use of 3-phase alternating current (AC), and since the late 1970 5, a large scale improvement of productivity and reduction of electric consumption have been realized by such technical innovations as introduction of secondary steel refining technology, enlargement of the furnaces, high electric power, oxygen-enriched operation, etc. Likewise, simultaneous developments were rapidly achieved in the lining, with water-cooling of the roof and sidewall, together with improvement of the refractory use technology, resulting in a significant decrease in refractory consumption. Moreover, bottom tapping and stirring by bottom-blowing have been introduced, and are widely used. Also, since the later 1980 5, direct current (DC) electric furnaces have been put into use, based on the development of large current rectifiers, gaining attention as a new electric steelmaking process with many advantages, whereby there was a rapid increase in use over the next decade. Accompanying these prominent technical developments in the steelmaking process, the requirements for refractory properties have changed accordingly, and the refractory practices have become much more complicated with respect to the different furnace types, the zones/regions of use, and the operating conditions. In this paper, the intent is to concisely describe the use and wear of refractories in electric arc furnaces, including discussion of the different refractories in electric arc furnaces, including discussion of the different refractories used (and the zones where they are applied), the history of material improvement, the present technical problems and the countermeasures, and the effect(s) of operating conditions.