Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 9, pp. 1729−1732.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
I.Yu. Aleksanyan, E.P. Dyachenko, V.V. Ermolaev, 2009, published in Khimicheskaya Promyshlennost’, 2009, Vol. 86, No. 3,
PROCESSES AND EQUIPMENT
OF CHEMICAL INDUSTRY
Improvement of Technology for Producing Pure Pyrolusite
from Carbonate Ores
I. Yu. Aleksanyan, E. P. Dyachenko, and V. V. Ermolaev
Astrakhan State Engineering University, Astrakhan, Russia
Received February 14, 2009
Abstract—The kinetics of the infrared drying of the solution of sulfonol in the foam state was studied on the basis
of experimental-analytical studies. Curves of dehydration and velocity of drying were get, their mathematical
simulation was executed. As a result of the analysis of the curves of the drying speed we made conclusion about
the mechanism of the transfer of water inside the product in the process of dehydration.
We can analyze the internal heat and mass transfer
at the infrared drying of the sulfonol in the foam state
only under the condition of a mandatory research of the
dehydration kinetics. We studied the dehydration kinetics
of the sulfonol according to experimental analytical
investigations. The main factors effecting on the drying
intensity were (1) a start diameter of a core of a foam
layer of a product d (m); (2) a heat ﬂ ow density E
), a start moisture of the sulfonol solution w
). We depicted the dehydration curves (Fig. 1)
and the drying velocity on results of a differentiation of
equations of the dehydration curves for speciﬁ c areas, and
also we determined approximating dependences of the
velocity and kinetic coefﬁ cients of the drying on factors
of the sulfonol being varied.
For the mathematical description of the drying curves
and velocity of a water removal the experimental data
were approximated by the polynomial of the sixth power.
In all cases the value of the reliability of approximation
was no less than 0.95.
The mathematical description of drying curves is
executed with the use of the polynomial dependence of
(w) = aw
+ gw + h,
where is a drying time, a, b, c, e, f, g, h are empirical
The approximation of the drying curves of the sulfonol
by the polynomial of the sixth power is presented on
According to the thermodynamic analysis points
of an inﬂ ection on the velocity curves of drying must
correspond to transition to the removal of moisture
with another qualitative and energy state of a bonding.
The internal mass transfer (the moisture transfer) is the
deciding in the drying of surfactants, in particular, of
sulfonol and the drying velocity is determined by the rate
of the moisture transfer inside the particle. Analysis of
the velocity curves for drying (Fig. 3) allows conclusions
about the mechanism of the moisture transfer [1, 2, 4].
It is convenient to approximate by the polynomial of the
Fig. 1. Experimental curves of the sulfonol drying at E = 3.232
, w = 0.5 kg kg
. (1) d = 3 mm, (2) d = 4 mm, (3) d =
5 mm, (4) d = 6 mm.