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
M. Moallem and A. Kiyoumarsi,
Volume 23, Issue 2 (1-2005)
Abstract
The rapid increase of non-linear loads in the last three decades has caused electrical quantities such as voltages and currents in 3-phase distribution systems to become distorted waveforms. This paper reviews, explains and discusses some new concepts, definitions and new available theory in the unbalanced and distorted systems. The usefulness of the proposed practical definitions is investigated by means of applying them to the real-world measurements of a three-phase electric arc furnace voltages and currents. Finally, the main power terms such as fundamental and non-fundamental power components, harmonic pollution, phase unbalance, active, reactive nonactive and distortion components are evaluated for a 3-phase arc furnace.
