CALCULATION OF EFFICIENCY
IN THE USE OF CERAMIC HEAT INSULATION IN PERIODIC FURNACES
A. V. Oistrakh
and V. I. Meshkov
Translated from Novye Ogneupory, No. 7, pp. 17 – 18, August, 2010.
Original article submitted May 20, 2010.
A calculation of the economic feasibility of applying fiber-ceramic heat insulation for hte lining of a periodic
furnace at OAO Volgogradneftemash instead of ShA-1 fireclay refractory is presented. The advantages of a fi
ber-ceramic lining by comparison with unitary lining are indicated.
Keywords: efficiency, periodic furnace, spray guniting, lining, fiber-ceramic block
The crisis in the metallurgical branch against the back-
ground of the world economic crisis has forced many market
participants to again review the cost of their output. An im-
portant component in the costs in metallurgical production
are production expenses associated with losses of heat in any
type of thermal equipment used for any function. One of the
principal causes of heat losses is seen in the high thermal
conductivity of the lining materials employed, in particular,
dense refractory brick and concrete.
Below, a calculation of the efficiency gained with the use
of fiber-ceramic lining by comparison with traditional lining
fabricated from unitary refractory bodies is presented. Since
many furnaces were constructed in the 1980s, the situation
that will be considered in this example, which involves a
change in lining, and the calculation presented below is of
special interest. Many specialists agree that fiber-ceramic
heat insulation is effective. The question is, how to check
that this is the case?
The computational data for the periodic furnace of OAO
Volgogradneftemash, which is also to be modernized, are as
follows: overall dimensions: length 8.7 m; width, 5.6 m;
height, 4.6 m; fuel, natural gas (price per 1 m
, 2.7 rubles);
maximal working temperature of furnace, 1000°C; rated
temperature of outdoor air, 20°C; temperature on furance
casing, 60°C; existing lining, ShA-1 fireclay brick, density
, thickness of lining, 600 mm; new lining,
LYTX-1260Z fiber-ceramic blocks, density 200 kg/m
thickness of lining, 225 mm.
In view of the overall dimensions of the furnace, the vol-
ume of the brick lining made of ShA-1 fireclay brick
amounts to 92 m
. Correspondingly, the weight of the lining,
given a density of the brick of 2000 kg/m
, will be
The quantity of heat Q needed to bring the given furnace
to the working temperature of 1000°C is calculated by means
of the formula
Q = Cm (t
where C is the specific heat capacity, kJ/(kg × K) and m the
weight of the lining.
The specific heat capacity of the basic refractory materi
als is the same and does not depend on their porosity, reflec
tion, chemical composition, or any other properties. The spe
cific heat capacity of the refractories is 0.96 kJ/(kg × K).
Thus, 173,317,939 kJ is needed to heat up the ShA-1 brick
lining of the given furnace to 1000°C.
Let us now calculate the amount of heat, and conse
quently, the amount of fuel, needed to heat up a lining made
of fiber-ceramic material.
A thickness of 200 mm (conservatively, 225 mm) is suf
ficient for a working temperature of 1000°C with density
when fiber-ceramic heat insulation is used. This
thickness was adopted assuming a lining of modular blocks,
though for the present conditions straight lining made of nee
dle-punching mats would also be adequate. With the existing
overall dimensions of the furnace, the volume of lining made
Refractories and Industrial Ceramics Vol. 51, No. 4, 2010
1083-4877/10/5104-0261 © 2010 Springer Science+Business Media, Inc.
From the proceedings of the International Conference of Metal
lurgists and Refractory Workers (April 22 – 23, 2010, Moscow).
OOO Teplopromproekt Trade House, Moscow.