A process has been developed to detoxify the waste magnesia-chromia bricks containing sexivalent chromium and recover valuable materials with arc plasma treatment. Especially magnesium and chromium, which are the major compounds of the waste bricks, could be separately recovered by carbothermic reduction with addition of iron. From the viewpoint of environmental protection and saving resources, such recovery processes are expected to be commercialized.

1.
Kojima, T., and Yoshida, T., 1996, “Reheat Treatment Method of MgO-Cr2O3 Brick After Used in Cement Rotary Kiln,” 12th Refractory Symposium, Japan, pp. 86–96.
2.
Winand
,
R.
, et al.
,
1990
, “
Production of Magnesium by Vacuum Carbothermic Reduction of Calcined Dolomite
,”
Trans. Inst. Min. Mettal. Sect. C.
,
99
, pp.
105
112
.
3.
Kubaschewski, O., and Alcock, C., 1990, Metallurgical Thermochemistry, 5th Edition, Pergamon Press, p. 268.
4.
Itagaki, O., 1980, Standard Gibbs Energy Change, Smelting of Nonferrous Metals, JIM, Japan, pp. 315–321.
5.
Eriksson
,
G.
, and
Hack
,
K.
,
1990
, “
Chemsage—A Computer Program for the Calculation of Complex Chemical Equilibria
,”
Metall. Trans. B
,
21
, pp.
1013
1023
.
6.
Katayama
,
H.
, and
Tokuda
,
M.
,
1979
, “
The Reduction Behavior of Synthetic Chromites by Carbon
,”
Iron Steel
,
65
, pp.
331
340
.
7.
Turkdogan, E., 1980, Physical Chemistry of High Temperature Technology, Academic Press, New York, NY, pp. 5–24.
You do not currently have access to this content.