Open AccessPilot-scale AC electric arc furnace plasma characterization
Author(s) -
Henri Pauna,
Thomas Willms,
Matti Aula,
Thomas Echterhof,
Marko Huttula,
Timo Fabritius
Publication year - 2019
Publication title -
plasma research express
Language(s) - English
Resource type - Journals
ISSN - 2516-1067
DOI - 10.1088/2516-1067/ab30dd
Subject(s) - plasma , electric arc , radiative transfer , inductively coupled plasma , arc (geometry) , plasma arc welding , electron temperature , electric arc furnace , atomic emission spectroscopy , brightness , atomic physics , emission spectrum , materials science , analytical chemistry (journal) , plasma parameters , slag (welding) , thermal , chemistry , optics , thermodynamics , metallurgy , physics , electrode , spectral line , geometry , environmental chemistry , mathematics , quantum mechanics , astronomy
Fundamental knowledge of the electric arc properties is important for the development of process control of electric arc furnaces. In this work, a pilot-scale AC electric arc has been studied with optical emission spectroscopy together with filtered camera footage. The properties of the arcs were determined with plasma diagnostics and image analysis in order to obtain both the characteristic plasma parameters and the physical form of the arc. The plasma temperatures, ranging from 4500 to 9000 K, were derived individually for three elements. The electron densities of the plasma were between 10 18 and 10 20 cm −3 and fulfilled the local thermal equilibrium criterion, but the plasma temperatures derived from atomic emission lines for different elements had high and unpredictable differences. The properties of the electric arcs have been studied with respect to the arc length derived from the image analysis. The slag composition, especially the relative FeO content of over 30%, was observed to have a notable effect on the brightness of the arc on slag and thus also on the radiative heat transfer.