This study used a CFD solver, CFX, to simulate the pulverized biomass refused-derived fuel (RDF) dynamic combustion behavior inside a wall-fired furnace, and investigated the effects of combustor geometry, pulverized biomass RDF traces, and burner positions on its performance under various operating conditions. The results showed that the interactions between various burners can affect the pulverized biomass RDF dynamic behavior significantly. In particular, the probability of pulverized biomass RDF hitting the wall is controlled by the down-fired rate as well as inlet conditions. Finally, the NOx concentrations inside the furnace are predicted in the optimal operating condition (Case 3). The results can be used as a design reference for the optimal operational combustion condition of pulverized biomass RDF.