  The abundances of CHNOS are crucial for the composition of planets. At the
onset of planet formation, large amounts of these elements are stored in ices
on dust grains in planet-forming disks. The evolution of this ice is affected
by dynamical transport, collisional processes, and the formation and
sublimation of ice. We aim to constrain the disk regions where these processes
are fully coupled, and develop a flexible modelling approach that is able to
predict the effects of these processes acting simultaneously on the CHNOS
budgets of the dust in these regions. We compared timescales associated with
these disk processes to constrain the disk regions where this approach is
necessary, and developed the SHAMPOO code, which tracks the CHNOS abundances in
the ice mantle of a single monomer dust particle, embedded in a larger
aggregate and undergoing these processes simultaneously. The adsorption and
photodesorption of monomer ices depend on the depth of the monomer in the
aggregate. We investigated the effect of fragmentation velocity and aggregate
filling factor on the amount of ice on monomers residing at r = 10 AU. The
locations where disk processes are fully coupled depend on both grain size and
ice species. Monomers embedded in aggregates with fragmentation velocities of 1
m/s are able to undergo adsorption and photodesorption more often compared to a
fragmentation velocity of 5 m/s or 10 m/s. Aggregates with a filling factor of
$10^{-3}$ are able to accumulate ice 22 times faster on average than aggregates
with a filling factor of 1. As different grain sizes are coupled through
collisions and the grain ice consists of multiple ice species, it is difficult
to isolate the locations where disk processes are fully coupled, necessitating
the development of the SHAMPOO code. The processing of ice may not be spatially
limited to dust aggregate surfaces for either fragile or porous aggregates.
