以非晶态合金催化剂SRNA-4为固相的气液固磁稳定床的界面传质研究

1 INTRODUCTION Magnetically stabilized beds (MSB) exhibit an unique combination of packed-bed and fluidized-bed properties. Gas-liquid-solid (G-L-S) three-phase MSB has recently attracted more attention in the field of biotechnology processes (such as bioseparation or immobilized enzyme systems) and chemical engi- neering(such as the hydrogenation reaction system). The interphase mass transfer behavior plays an im- portant role in the optimal operation of practical MSB. However, many…

Interphase Mass Transfer in G-L-S Magnetically Stabilized Bed with Amorphous Alloy SRNA-4 Catalyst

Gas-liquid (G-L) and liquid-solid (L-S) mass transfer coefficients were characterized in a gas-liquid-solid(G-L-S) three-phase magnetically stabilized bed (MSB) using amorphous alloy SRNA-4 as the solid phase. Effects such as superficial liquid velocity, superficial gas velocity, magnetic strength, liquid viscosity, and particle size were investigated. Experimental results indicated that the G-L volumetric mass transfer coefficients (KLa) increased along with the magnetic strength, superficial gas and liquid velocities. Proper increase of liquid viscosity promoted KLa only in the range of lower liquid viscosity. The external magnetic field made L-S mass transfer coefficients (Ks)in the G-L-S MSB lower than those of conventional fluidized beds. Ks in the MSB almost kept constant as the superficial liquid velocity and superficial gas velocity increased and decreased with the liquid viscosity and surface tension, while increased with the particle size Ks showed uniform axial and radial distributions except of small decreases close to the wall. Dimensionless correlations were established to estimate KLa and Ks of the MSB with SRNA-4 catalysts, which showed the average error of 5.4% and 2.5% respectively.