Hydrodynamic behaviors of sand particles in a large-scale triple bed combined circulating fluidized bed

Abstract

We have developed a triple-bed combined circulating fluidized bed (TBCFB) as a gasifier for advanced integrated coal gasification combined cycle (A-IGCC) or advanced integrated coal gasification fuel cell combined cycle (A-IGFC) systems to improve of thermal efficiency of coal-fired power plants. In this study, the effect of operating conditions in a gas-sealing bed (GSB) (Φ0.15 m×5.0 m) between a riser (Φ0.1 m×16.6 m) and a bubble fluidized bed (0.75 m×0.27 m×3.4 m) on flow behaviors of silica sand solids in a large-scale TBCFB cold model were investigated in order to achieve high flux and high density solids circulation. The solids mass flux (G s) monotonically increased with the increase in gas velocity in the GSB. Further increase in GSB gas velocity decreased G s.