ISSN 1070-4272, Russian Journal of Applied Chemistry, 2016, Vol. 89, No. 5, pp. 800í804. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © O.M. Flisyuk, N.A. Martsulevich, O.N. Krukovskii, 2016, published in Zhurnal Prikladnoi Khimii, 2016, Vol. 89, No. 5, pp. 668í672.
Fluidized-Bed Granulation of Ammonium Sulfate from Solution
Formed as By-Product in Production
of Manganese Oxides
O. M. Flisyuk, N. A. Martsulevich, and O. N. Krukovskii
St. Petersburg State Institute of Technology (Technical University), Moskovskii pr. 26, St. Petersburg, 109013 Russia
e-mail: ﬂ firstname.lastname@example.org
Received May 17, 2016
Abstract—Fluidized-bed granulation of ammonium sulfate from the solution formed as by-product in produc-
tion of manganese oxides was subjected to theoretical and experimental study. The evolution of the particle-size
distribution in relation to the process conditions was examined, and the adequacy of the suggested mathematical
model was checked.
A procedure is known for producing manganese oxides
by treatment of a manganese sulfate solution with
oxygen or air in the presence of ammonia [1, 2]. The
formation of manganese oxides can be described by the
following reaction equation:
Thus, the production of manganese oxides involves
formation of a by-product, ammonium sulfate solution,
in an amount approximately 1.5 times larger than
the amount of the target product. On the other hand,
ammonium sulfate is an excellent nitrogen fertilizer and
can be used both independently and as a component in
production of mixed fertilizers. The manganese content
of ammonium sulfate is low, no more than 1–1.5%, and
its presence makes the fertilizer still more valuable.
Ammonium sulfate is produced today also at
coke plants. The generated coke gas is treated to
remove ammonia in absorbers with the formation of
an ammonium sulfate solution, which acts as a raw
material in the production of crystalline and granulated
ammonium sulfate [3, 4].
Production of ammonium sulfate in the granulated
form is preferable, because in this form the product
does not form dust and is convenient in use, storage,
and transportation. The most promising procedure
for preparing a granulated product is ﬂ uidized-bed
granulation. This process has been well studied by now
[5–7], but the evolution of the particle-size distribution
and the inﬂ uence exerted on it by the process parameters
are understood insufﬁ ciently, which hinders the use of
this procedure for commercial production of granulated
This work consists in theoretical analysis of the
ﬂ uidized-bed granulation of ammonium sulfate from
solution and in experimental study of the process,
aimed at estimating the particle-size distribution of the
product and at checking the adequacy of the suggested
mathematical description to the real process.
Preliminary experimental studies on the granulation
of ammonium sulfate from solution in a ﬂ uidized-bed
apparatus have shown that the process is not accompanied
by crushing of the granules in the apparatus in the course
of granulation. Therefore, organization of the stable
process requires internal recycle, i.e., feeding of ﬁ ne
particles acting as granule formation nuclei into the bed.
Experimental studies have shown also that ﬂ uidized-bed