Efficient handling and separation of biomass-derived particulate streams are critical to the performance and sustainability of bioenergy conversion systems, particularly in thermochemical processes such as biomass combustion and gasification. Cyclone separators are widely employed for removing entrained biomass residues and inorganic particles from process gas streams; however, their performance under high solids loading and heterogeneous biomass conditions remains inadequately understood. In this study, the influence of vortex finder geometry on gas–solid separation performance is investigated for cyclone systems operating with biomass-derived particulate mixtures. Five vortex finder configurations—flat, wedged, curved, tapered in–out, and hyperboloid—are systematically evaluated and benchmarked against an experimentally validated reference design. A two-way coupled CFD–DEM approach is used to resolve gas–solid interactions, inter-particle collisions, and wall contacts for heterogeneous biogenic–mineral mixtures representative of biomass residues, including plant-based particles and sand. Simulations conducted at an inlet gas velocity of 30 m/s and a solids feed rate of 2.53 kg/s demonstrate that vortex finder geometry strongly influences flow stability, particle residence time, re-entrainment, and pressure drop. The flat vortex finder yields the most stable vortex structure and the highest separation efficiency, thereby improving gas cleanliness and reducing solids carryover. These findings provide mechanistic insight into cyclone operation under biomass-relevant conditions and offer practical guidance for the design of gas-cleaning units to enhance the efficiency, reliability, and sustainability of bioenergy systems. • Cyclone geometry affects biomass residue separation in bioenergy systems. • Vortex finder design controls solids carryover and gas cleanliness. • CFD–DEM captures heterogeneous biomass–particle interactions. • Flat vortex finders improve separation under high biomass loading. • Results support improved gas cleaning for bioenergy conversion.
El‐Emam et al. (Tue,) studied this question.