REFRACTORIES IN HEATING UNITS
HIGH-DURABILITY LINING FOR AN ORE-ROASTING FURNACE
V. V. Slovikovskii
and A. V. Gulyaeva
Translated from Novye Ogneupory, No. 5, pp. 7 – 10, May, 2015.
Original article submitted December 17, 2014.
The goals of this investigation were to analyze the reasons for the short service life of the lining of an
ore-roasting furnace used to roast argillites and to determine the mechanism responsible for wear of the lining.
The new design developed for the electric furnace based on the results from the analysis has ensured safe oper
ation of the furnace, increased the value of the time-based utilization factor (from 0.33 to 0.73), increased the
size of the charge that can be processed, decreased the number of repairs, and reduced electric-power con
sumption. The service life of the lining has increased from three to 16 months. A similar lining that includes
carbon blocks in the furnace bottom has been installed in an electric furnace used to make lead at the Lenin-
grad Polymetallurgical Combine.
Keywords: lining, ore-roasting furnace, refractories based on fused grains, periclase-chromite and chro-
mite-periclase refractories, carbon blocks.
To conserve refractories, it is very important to have a
lining that undergoes uniform wear over its entire surface.
Such linings can be obtained by employing a differentiated
design that combines refractories which differ in their resis-
tance to reactants in the roasting operation and the furnace
gases. There have been studies of the installation of combi
nation linings in furnaces used in nonferrous metallurgy
[1 – 3]. VNIIénergotsevtmet (the All-Russian Scientific Re
search Institute of Energy in Nonferrous Metallurgy) has de
veloped and introduced combination lining systems to im
prove the durability of the most heavily worn zones of lin
ings in high-temperature equipment . In this article, we
examine the experience of the specialized company “An
grenénergotsvetmet” with the use of a combination lining for
an ore-roasting furnace. In order to properly choose the
refractories, find an efficient method of constructing the lin
ing, and determine ways to make it more durable, it is neces
sary to know the service conditions and character of failure
of the lining in relation to different factors and to also know
the technical capabilities of the refractories that are used.
The lining of the electric furnace used at Angrenénergo
tsvetmet to roast argillites lasted three months. The furnace
had a forced-cooling system: the bottom was air-cooled,
while the roof and the walls were cooled with process water
supplied to cooling jackets; the roof was made of five jackets
joined to one another by tenons covered by a chrome-
magnesite bulk refractory. The walls of the furnace consisted
of two courses of water-cooled jackets: a top course and a
bottom course. The top course contained 15 jackets con
nected by tenons that were covered with the chrome-
magnesite refractory. The lining of the bottom course of
jackets was made of the chrome-magnesite refractories and
the bottom was constructed of fireclay and chrome-
magnesite refractories and 400-mm-high carbon blocks. The
blocks were not sintered to one another, which led to penetra
tion of the joints by metal.
To create an efficient design for the lining of the electric
furnace, we tested the following types of refractories to ob
serve their interaction with melts of slag and the metallic and
sulfide phases: PKhPU — periclase-chromite refractories
based on fused periclase-chromite; KhM — chromite-peri
clase refractories; PKhS — periclase-chromite refractories;
MPM — fused periclase refractories; ShB — fireclay
refractories; PO — carbon refractories. The properties of the
refractories are shown in Table 1. The tests were conducted
by immersing specimens of the refractories in melts of slag
and the metallic and sulfide phases. The specimens were pre
Refractories and Industrial Ceramics Vol. 56, No. 3, September, 2015
1083-4877/15/05603-0221 © 2015 Springer Science+Business Media New York
Ural Federal University, Ekaterinburg, Russia.