EFFECT OF FORM OF RAW MATERIALS FOR PREPARATION
OF A GLASS CHARGE ON REFRACTORY CORROSION
N. I. Min’ko
and E. A. Laz’ko
Translated from Novye Ogneupory, No. 4, pp. 48 – 52, April, 2012.
Original article submitted October 18, 2011.
Questions of reaction kinetics are considered for a glass charge based on traditional and unconventional raw
materials from different deposits with refractory materials used for lining the basin and upper structure of a
Keywords: glass charge, refractory corrosion, glass-resistance, bath furnace, alkali melt, mineral raw
The most consuming item in the glass industry is the
main production unit, i.e., glass-melting furnace. The eco-
nomic efficiency of an enterprise mainly depends on its cam-
paign duration. During cold repair the cost of refractory ma-
terials reaches 80% of the overall sum consumed for building
a furnace. Therefore an attempt is made in the construction
of furnaces for glass production to use high quality
refractories with improved glass resistance and strictly main-
tained dimensions (wall assembly). Contact of a charge and
glass mix with refractory is unavoidable. In order to achieve
a fifteen year campaign life, as occurs in the float lines of
Pilkington (Great Britain), glass and refractory specialists are
set the task of resolving a considerable problem.
Glass resistance of a refractory is a function of many
components of the production process for glass melting;
glass composition, temperature, melting duration, oxida
tion-reduction atmosphere of a furnace, oxide composition of
a glass mixture, its viscosity, volatility of charge compo
nents, etc. .
In a bath furnace the greatest breakdown (corrosion) is
observed in the region of charging hoppers, when in the bath
and upper furnace structure there is predominantly action not
only of highly alkaline melt and its evaporation products, but
also a charge represented by a mechanical mixture of refrac
tory and readily melting components, exhibiting different
corrosion activity with respect to ceramic or fusion-cast re
fractory. In the glass making and cooling parts of a furnace,
when there is no charge, and all of the corrosive components
are bonded in complex compounds or melt, corrosion is sig
nificantly less expressed in spite of a higher temperature than
in the charging hopper and in the area of area of charge.
Erosion of refractory materials leads to shortening of the
period between repairs and is also a reason for appearance of
such production form of glass scrap that are difficult to over-
come as bubbles, stria, and pockets. If refractory material ex-
hibits considerable porosity, then its breakdown under the ac-
tion of a melt “opens” pores, filled with gaseous products; in
a number of cases gas formation is accompanied by chemical
processes occurring in contact with the main or impurity
component of a refractory composition with a glass melt.
A transitional layer arises at a refractory – melt interface,
enriched with breakdown products, whose composition dif
fers markedly from the glass composition. With entry of this
layer into the production stream there is development within
objects of stria of chemical origin and gas inclusions as a re
sult of disturbance of gas solubility equilibrium in a melt.
Corrosion of a bath lining in the upper structure of a furnace
may lead to breakaway of refractory and falling into a glass
melt. As a result of this inclusions appear in a glass object,
i.e., scale surrounded by a striated “halo” of products of in
completely dissolved lumps of refractory.
The main commercial aim of any production is a reduc
tion in manufacturing cost with simultaneous maintenance or
improvement of its quality. A glass object is no exception.
Following expenditure in furnace building and maintenance
there is expenditure for acquiring raw material. Here reserves
for reducing costs may:
– use of mineral raw material, for example sands from
new deposits (as a rule at places close to an enterprise);
Refractories and Industrial Ceramics Vol. 53, No. 2, July, 2012
1083-4877/12/05302-0139 © 2012 Springer Science+Business Media, Inc.
GBOUVPO V. G. Shukin, Belgorod State Technological Univer
sity, Belgorod, Russia.