IMPROVING THE REFRACTORY LINING DURABILITY
OF PYROMETALLURGICAL PLANTS IN SERVICE
AT THE SVYATOGOR JOINT-STOCK Co.
V. G. Kozhin,
V. V. Belyaev,
and E. N. Selivanov
Translated from Novye Ogneupory, No. 10, pp. 22 – 25, October, 2003.
Factors responsible for the failure of the refractory brick lining of pyrometallurgical plants in service at the
Svyatogor JSC are considered, of which the major ones are: corrosion due to the attack from high-iron sili
con-containing slag, infiltration of molten mass causing fracture during the heat-and-cool thermal cycling, and
mechanical impact. Measures that allowed the refractory consumption rate to be reduced to 0.035 tons per ton
of blister copper are described.
Expenses on the refractory materials for installation and
repair of industrial furnaces account for a significant percent-
age of the metal cost; for this reason, increasing durability of
the lining and decreasing the refractories’ expenditure rate is
an issue of major concern for any metallurgical plant. The
service life of the lining of a pyrometallurgical processing
unit can be extended by using high-performance refractories
and protecting cooling facilities .
Consumption of refractories at the Svyatogor JSC has
primarily been associated with copper smelting technology:
concentrate calcination, cinder-to-matte reverberatory melt
ing, and conversion of matte to blister copper. For the lining
of heavy-duty sections of a pyrometallurgical units, PKhSU-
and PKhSS-grade periclase-chromite and KhP-grade chro
mite-periclase refractories have been used.
Incoming inspection data (Table 1) show that the con
centration of Cr
in the yearly delivered PKhSU- and
PKhSS-grade periclase-chromite refractories was virtually
constant, whereas that of MgO tended to decrease by 4.5%.
Under theses conditions, even a slight increase in relatively
low-melting components (for example, SiO
) leads to a re
duced service life of the refractories, which requires that
measures be taken to prevent damage to the lining.
Slag attack is one of the factors that causes destructive
damage to refractories. So, high-FeO silicate slag enters into
a reaction with the periclase lining material at 1200°C to
yield liquid phases in the MgO – SiO
– FeO system. The
slag solubility of chromite and periclase increases with tem
perature and FeO concentration in the oxide melt .
Sulfide melt (matte), by diffusing into the refractory ma-
terial , provides the conditions for conglomerates com-
posed of phases with different thermal expansion. Subjected
to thermal (heat-and-cool) cycling, such conglomerate are
prone to cracking and breakup.
To gain a deeper insight into the factors responsible for
the failure of the lining, PKhSU-grade components with sin-
gle-compaign service time in a copper converter were exam-
ined. The test specimens were sampled along the axis of the
component spaced a distance 5, 20, 45, 75, and 120 mm apart
from the hot end. It follows from chemical analysis data (Ta
ble 2) that the surface layer to a depth of more than 5 mm
was infiltrated with matte and was thus enriched with copper,
Refractories and Industrial Ceramics Vol. 45, No. 4, 2004
1083-4877/04/4504-0228 © 2004 Springer Science+Business Media, Inc.
Svyatogor Joint-Stock Co., Krasnouralsk, Russia; Institute of
Metallurgy and Materials Science (IMET), Ural Branch of the
Russian Academy of Sciences, Ekaterinburg, Russia.
TABLE 1. Average Composition of PKhSU- and PKhSS-
Refractories (yearly delivery)
Concentration of oxides
in PKhSU- and PKhSS-grade materials, %
1995 77.98 12.46 –
1996 77.18 12.78 –
1997 77.54 11.63 –
1998 76.75 12.13 4.22
1999 76.62 11.82 5.47
2000 73.81 10.83 5.09
2001 73.53 12.16 7.26
2002 73.52 12.53 4.26
GOST 10888–93 > 65 7 – 15 –
Based on incoming inspection data.