  We introduce a model for the explicit evolution of interstellar dust in a
cosmological galaxy formation simulation. We post-process a simulation from the
Cosmic Reionization on Computers project (CROC, Gnedin 2014), integrating an
ordinary differential equation for the evolution of the dust-to-gas ratio along
pathlines in the simulation sampled with a tracer particle technique. This
model incorporates the effects of dust grain production in asymptotic giant
branch (AGB) star winds and supernovae (SN), grain growth due to the accretion
of heavy elements from the gas phase of the interstellar medium (ISM), and
grain destruction due to thermal sputtering in the high temperature gas of
supernova remnants (SNRs). A main conclusion of our analysis is the importance
of a carefully chosen dust destruction model, for which different reasonable
parameterizations can predict very different values at the $\sim 100$ pc
resolution of the ISM in our simulations. We run this dust model on the single
most massive galaxy in a 10$h^{-1}$ co-moving Mpc box, which attains a stellar
mass of $\sim 2\times10^9 M_{\odot}$ by $z=5$. We find that the model is
capable of reproducing dust masses and dust-sensitive observable quantities
broadly consistent with existing data from high-redshift galaxies. The total
dust mass in the simulated galaxy is somewhat sensitive to parameter choices
for the dust model, especially the timescale for grain growth due to accretion
in the ISM. Consequently, observable quantities that can constrain galaxy dust
masses at these epochs are potentially useful for placing constraints on dust
physics.
