  The snowlines of various volatile species in protoplanetary disks are
associated with abrupt changes in gas composition and dust physical properties.
Volatiles may affect dust growth, as they cover grains with icy mantles that
can change the fragmentation velocity of the grains. In turn, dust coagulation,
fragmentation, and drift through the gas disk can contribute to the
redistribution of volatiles between the ice and gas phases. Here we present the
hydrodynamic model FEOSAD for protoplanetary disks with two dust populations
and volatile dynamics. We compute the spatial distributions of major volatile
molecules (H$_2$O, CO$_2$, CH$_4$, and CO) in the gas, on small and grown dust,
and analyze the composition of icy mantles over the initial 0.5 Myr of disk
evolution. We show that most of ice arrives to the grown dust through
coagulation with small grains. Spiral structures and dust rings forming in the
disk, as well as photodissociation in the outer regions, lead to the formation
of complex snowline shapes and multiple snowlines for each volatile species.
During the considered disk evolution, the snowlines shift closer to the star,
with their final position being a factor $4-5$ smaller than that at the disk
formation epoch. We demonstrate that volatiles tend to collect in the vicinity
of their snowlines, both in the ice and gas phases, leading to the formation of
thick icy mantles potentially important for dust dynamics. The dust size is
affected by a lower fragmentation velocity of bare grains in the model with a
higher turbulent viscosity.
