We develop a Monte Carlo event generator based on the combination of a parton production formula including the effects of parton saturation (called the DHJ formula) and a hadronization process due to the Lund string fragmentation model. This event generator is designed for the description of hadron productions at forward rapidities and in a wide transverse momentum range in high-energy proton-proton collisions. We analyze transverse momentum spectra of charged hadrons as well as identified particles, including pion, kaon, and (anti)proton at RHIC energy and ultraforward neutral pion spectra from the LHCf experiment. We compare our results to those obtained in other models based on parton-hadron duality and fragmentation functions.