OPERATION OF A COMBINED GAS HEATING SYSTEM
FOR FIRING REFRACTORY COMPONENTS IN A TUNNEL FUNNEL
AT THE KAZOGNEUPOR PLANT
B. A. Unaspekov
Translated from Ogneupory i Tekhnicheskaya Keramika, No. 10, pp. 47 – 50, October, 2002.
The operation of an advanced heating system for a tunnel system is described and ways toward its further im
provement are proposed.
The ever-increasing requirements on the quality of cal-
cined aluminosilicate refractories call for attaining high tem-
peratures (1700 – 1800°C) in the work space of tunnel fur-
In batch-operated furnaces, the required high tempera-
tures can be readily attained. However, this entails certain
disadvantages such as high fuel consumption per unit of pro-
duction and low degree of technical service.
High-temperature tunnel furnaces with a combined (in
jector) system of gas heating  provide a promising solu
tion to the problem with respect to obtaining high tempera
tures and effective control over the heating regime.
Crosswise and lengthwise sectional views of the tunnel
furnace (designer: St. Petersburg Refractory Institute; manu
facturer: Kazogneupor Plant) are shown in Fig. 1. A specific
design of the combined system of gas heating in this furnace
is the efficient offtake of hot air at the required temperature
from the cooling zone by means of injectors. The gas burner
and ejector facilities enable the gas and hot air to be mixed at
a ratio close to stoichiometric. The mixture burns up in the
work space with a high calorific effect, which allows the re
quired temperatures to be achieved in positions according to
the firing technology.
Double-pipe mixing burners of the “tube-in-tube” type
(a total of 36) were mounted in the high-temperature furnace.
The gas and air inlet burner pressure was controlled within
5 – 10 and 2.0 – 3.5 kPa, respectively. The gas flow rate was
specified individually for each burner depending on its func
tion. The essential parameters of jet facilities installed in the
combined gas-heating system of the high-temperature ac-
cording to Recommendations  are listed in Table 1.
Refractories and Industrial Ceramics Vol. 43, Nos. 9 – 10, 2002
1083-4877/02/0910-0319$27.00 © 2002 Plenum Publishing Corporation
Almatyintergaz Joint-Stock Co., Alma-Ata, Kazakhstan.
Fig. 1. Lengthwise (a) and crosswise (b ) sectional views of a
high-temperature tunnel furnace with a combined system of gas
heating; 1 ) buggy; 2 ) components; 3 ) ejector channel; 4 ) injector;
5 ) air nozzle; 6 ) window; 7 ) shutter (gate); 8 ) ejector; 9 ) gas