S. Aminorroaya and H. Edris,
Volume 21, Issue 1 (7-2002)
Abstract
In electric arc furnace steelmaking units, the essential parameters are reducing price, increasing production and decreasing environmental pollution. Electric arc furnaces are the largest users of electric energy in industry. The most important techniques that can be used to reduce the electric energy consumption in electric arc furnaces are scrap preheating, stirring, use of burners and hot charge and foamy slag. Between these methods, the use of foamy slag is the most useful and economical factor. Foamy slag can reduce the amount of energy, electrodes, refractory consumption, and tap to tap time while it also increases productivity.
In this study, method of production and optimum conditions for foamy slag in a 200-ton electric arc furnace were investigated. The use of foamy slag in this research can reduce the electric energy consumption from 670 to 580 kwh/t and the melting time from 130 to 115 min. and that the electric power input can be increased. It also shows that with foamy slag, the optimum amount of FeO in slag is 20-24 percent and the optimum basicity is 2-2.2.
Keywords: electric arc furnace, energy, DRI, foamy slag
A. Faeghinia, H. Mardi,
Volume 38, Issue 4 (1-2020)
Abstract
Amorphous steel slag was blended with different concentrations of waste glass (20, 40, 50, 60, 70 wt.%) and SiC to obtain a composite. According to Hot Stage Microscopy images, slag-glass composite contractions started at 1050 ºC. scanning electron microscope micrographs of slag-SiC (foaming agent) composite revealed tunnel-like porosities of 500 to 1000 microns. Gaseous products of carbide decomposition led to the formation of these tunnel-like porosities. By adding up to 50 wt. % of waste glass to this composite and sintering at 1200 ° C, the size of cavities decreased by 10 times and achieved 50 microns to form spherical cavities. By increasing glass content, the total porosity of slag-glass-SiC increased to 80 wt.% followed by a decrease in the strength to 3.2 MPa. Having an overall density of 0.8 g/cm3, the slag-glass composite could be classified as a porous foam material. Pseudo Waltonite phase was also detected in this composite after sintering.
