Effect of Pressure on Solids Flow Characteristics in Recycle System of a Circulating Fluidized Bed

Solids flow characteristics have been determined in a pressurized solids recycle systems of silica sand particles for the application in a pressurized CFB(PCFB). The solids recycle system is composed of a downcomer(0.10 m i.d. 2.25 m high) and a loop-seal(0.10 m i.d.). The silica sand(d(p) = 240 mu m, rho(s) = 2,582 kg/m(3)) particles were transported at room temperature and system pressure(P-svs) up to 0.71 MPa using air. Solids mass flux(G(s)) increases with increasing system pressure at constant aeration rate. Pressure gradient, solids velocity and actual gas velocity increase with increasing P-sys at constant aeration rate. The Pressure drop number(Phi) on pressure gradient in downcomer has been correlated with Transportation number(Tr). Pressure drop across the loop-seal increases with increasing of G(s) irrespective of variation of P-sys. The obtained G(s) and Transportation number(Tr) have been correlated with the experimental variables.