Abstract: In this research, a glued-sphere discrete element method was implemented in the open-source, computational fluid dynamics software MFiX. The implementation was verified using a cylinder-wall collision and then validated by simulating the packing and fluidization of nonspherical particles. The validated code was applied to simulate fast pyrolysis of nonspherical biomass particles in a bubbling fluidized bed. The glued sphere occupancy ratio was proposed to quantify the quality of shape resolution using glued sphere. Shape resolution showed significant influence on the packing height in the simulation of particle packing and an occupancy ratio of 80% was recommended. Its influence is minor in fully fluidized bed but can be eight times higher in packed bed. Three tested heat transfer models predicted similar yields of elongated biomass fast pyrolysis. The solver developed in this research can be used to simulate other multiphase reacting flows involving nonspherical particles.