When　the　valuable　metals　in　the　hydrodesulphurisation　(HDS)　catalysts　are　recovered　by　the　pyrometallurgical　process,　the　traditional　roasting　method　is　prone　to　the　problem　of　insufficient　oxidative　conversion　of　metal　sulfides.　However,　the　residual　oil　and　carbon　in　the　spent　HDS　catalysts　cannot　be　effectively　utilized,　resulting　in　additional　energy　consumption.　Fluidized　roasting　in　a　boiling　furnace　is　a　good　way　to　use　residual　oil　and　carbon　to　provide　heat　for　roasting　while　oxidizing　the　metal　sulfides　in　the　spent　HDS　catalyst.　This　study　used　computational　fluid　dynamics　(CFD)　coupled　with　the　Coarse　-Graining　model　(CGM)　to　simulate　the　fluidized　roasting　effect　of　HDS　catalysts　at　different　initial　bed　heights　and　gas　velocities　in　a　large-scale　industrial　boiling　furnace.　To　improve　the　fluidized　roasting　quality　and　reduce　the　energy　consumption,　it　is　recommended　that　the　optimal　initial　bed　height　(　H　0　)　is　0.45　m,　the　gas　velocity　(　u　g　)　is　1.45　m/s.　The　gas　consumption　and　the　net　energy　saving　were　0.34　m　3　/kg　and　2.29　x　10　10　J　under　this　condition.　Accordingly,　the　theory　of　the　competitive　relationship　between　particle　collision　and　bubble　fragmentation　is　innovatively　proposed,　and　the　distribution　change　of　the　turbulent　energy　intensity　zone　verifies　this　theory.