  We study mass ejection from a binary neutron star merger producing a
long-lived massive neutron star remnant with general-relativistic
neutrino-radiation hydrodynamics simulations. In addition to outflows generated
by shocks and tidal torques during and shortly after the merger, we observe the
appearance of a wind driven by spiral density waves in the disk. This
spiral-wave-driven outflow is predominantly located close to the disk orbital
plane and have a broad distribution of electron fractions. At higher latitudes,
a high electron-fraction wind is driven by neutrino radiation. The combined
nucleosynthesis yields from all the ejecta components is in good agreement with
Solar abundance measurements.
