PROSPECTS FOR USING ALUMINOSILICATE REFRACTORIES
FOR ALUMINUM ELECTROLYZERS.
PART 1. FEATURES OF THE STRUCTURE OF ALUMINOSILICATE
REFRACTORIES INTENDED FOR ALUMINUM ELECTROLYZERS
V. V. Sharapova,
B. P. Sereda,
D. Yu. Boguslavskii,
I. P. Malyshev,
V. D. Troyan,
and N. A. Troshenkov
Translated from Novye Ogneupory, No. 9, pp. 20 – 23, September 2007.
Original article submitted July 5, 2007.
Comparative analysis is provided for the structure and properties of aluminosilicate refractories grade ShPD.
It is established that refractory ShPD
-45, produced with the use of an addition of mullite-corundum chamotte
surpasses in all characteristics refractories prepared by the normal technology. Refractory ShPD
-45 may be
recommended for use in aluminum electrolyzers.
The service life of the lining of the cathode assembly of
an aluminum electrolyzer is an important engineering para-
meter. In order to avoid penetration of subsidiary products of
an electrolyzer into the lining a refractory layer is laid down
under hearth blocks of the electrolyzer. Sodium vapor and
fluorine compounds, diffusing into the refractory layer, lead
to a change in its chemical-mineral and phase compositions
and destruction of the refractory itself, as for the cathode
lining of the aluminum electrolyzer as a whole, and therefore
the question of selecting the grade of refractory remains im
There is currently use of aluminosilicate refractories for
the refractory layer. The chemical and phase composition of
chamotte refractories is determined by the raw material com
position and properties. In turn the properties of the alumino
silicate articles depend not only on the Al
them, but also on the overall total sum of fluxes and often on
their chemical nature . The degree of mullitization, the
composition of mullite, and the glassy phase in chamotte
refractories, depend on the properties of the original raw ma-
terial, firing temperature and duration.
Properties are provided in the present communication for
the characteristics and phase composition of chamotte dense
articles of ShPD produced by traditional technology
(ShPD-43), and with the use of addition of mullite-corundum
-45). Studies were carried out petrographi
cally in reflected and transmitted light in microscopes MBI-6
and MN-8 respectively. Articles made of ShPD
-45 with ad
dition of mullite-corundum chamotte in production proper
ties and phase composition somewhat exceed those for ar
ticles made of ShPD-43 prepared by normal technology. The
physicochemical indices of ShPD, prepared by both produc
tion methods, are provided in Table 1.
The average apparent density of specimens of the corre
sponding type of refractory was determined by hydrostatic
weighing. Open porosity of ShPD
-45 articles was lower by
a factor of 1.5, and the average density was higher by a factor
of 1.1 than for articles without mullite-corundum chamotte.
Since open porosity is connected with the nature of pores,
Refractories and Industrial Ceramics Vol. 48, No. 4, 2007
1083-4877/07/4804-0246 © 2007 Springer Science+Business Media, Inc.
UkrNIIspetsstal’, ZGIA, OAO ZAlK, OAO Zaporozhogneupor,
TABLE 1. Physicochemical Indices of ShPD Refractories
Weight fraction, %
Open porosity, %
in compression, MPa
-45 48.7 1.2 1.3 8 2.43 0.08 90 (850°C)
ShPD-43 43.2 1.5 1.4 12 2.29 0.092 72 (20°C)