STUDY OF THE THERMAL CONDUCTIVITY
OF HEAT INSULATION OBJECTS BASED ON BEIDELLITE CLAY
AND ASH MATERIAL
V. Z. Abdrakhimov,
V. A. Mikheev,
and E. S. Abdrakhimova
Translated from Novye Ogneupory, No. 7, pp. 50 – 52, July 2011.
Original article submitted November 29, 2010.
It is established that use of ash material within ceramic compositions based on beidellite clay makes it possible
to prepare heat insulation objects with improved thermotechnical properties.
Keywords: heat insulation objects, thermal conductivity, ash material, beidellite clay.
As is well known, it is impossible to make the outer layer
of a furnace from refractory brick since in this case there is
an increase in fire hazard. Chamotte brick warms more rap-
idly and strongly at the same temperature than heat insula-
tion material, and it expands more strongly. For the outer
layer it is desirable to use heat insulation objects NK-23
(ShL-0.45) according to TU 15441-037-22298789–2007 (ap-
plication temperature 1200°C) with a size of 250 ´ 120 ´ 65 mm
grade not below M150.
Results are presented in this article for an experimental
study of the thermal conductivity of heat insulation objects
based on badelleyite clay and ash material. The main clay
raw material for producing heat insulation objects uses clay
of the Obraztsov deposit. It has medium fineness, primarily
with a low content of fine and medium size inclusions, repre
sented by quartz, iron minerals, gypsum, and carbonate in
clusions [1, 2], The main rock forming mineral of Obraztsov
clay is beidellite Al
O clay (Fig. 1), named
after the location of Beidell, Colorado State (USA), and re-
lating to minerals of the motmorillonite group [1, 2]. The
clay with respect to refractoriness (1320 – 1350°C) relates to
readily melting clay. The upper limit of refractoriness is
close to that of refractory clays. Obraztsov clay with respect
content (see Table 1) relates to the group semiacid
raw materials [1, 2], and with respect to iron oxide content to
a group with a high colored oxide content.
With respect to grain size composition the Obraztsov de-
posit relates to a group of medium-fine raw material. It is
highly sensitive towards drying, and has high specimen
shrinkage. Concerning ductility (its ductility number is
18 – 24), the clay may be identified as medium-ductile.
For the production of heat insulation objects as shorten
ing and burn-off addition ash material of the Togliatti ther
mal power station [3, 4] is used. The ash is loose material of
black or gray color. Apart from mineral substances, there is
an organic component within it. The chemical composition
of the ash material is presented in Table 1, and the micro
structure is shown in Fig. 2. The mineral composition of the
ash material is, wt.%: amorphized clay substance 10 – 20,
Refractories and Industrial Ceramics Vol. 52, No. 4, November, 2011
1083-4877/11/05204-0285 © 2011 Springer Science+Business Media, Inc.
Samara Academy of State and Municipal Management, Samara,
S. P. Korolev Samara State Aerochemical University (National
Research University), Samara, Russia.
TABLE 1. Starting Material Chemical Composition
CaO MgO R
Beidellite clay 54.38 19.46 8.52 1.75 1.82 2.73 1.82 8.42
Ash 48.15 16.70 7.42 3.99 2.36 0.10 0.90 20.84