Gas Phase Pressure Drop Characteristics Of Parallel And Countercurrent In Rotating Packed Bed

Rotating packed bed(RPB),a new efficient chemical mass transfer equipment,is widely used in chemical separation,preparation of new materials,environmental protection and other fields because of its small size and high mass transfer efficiency In the industrial application,the gas pressure drop of the equipment is an important index for the selection and engineering design of the high gravity rotating bed,which is related to the energy consumption of the equipment gas transmission power.A self-made parallel and counter current RPB with liquid spraying in the outer chamber was developed.The experiment was carried out with air water as experimental system and high gravity factor,gas velocity and liquid spray density as influencing factors.The inlet,external cavity,packing layer and outlet pressure drop models are established respectively.Combined with experimental data and pressure drop model,CFD numerical model was used to visualize the pressure drop characteristics of parallel and countercurrent gas phase in RPBThe results show that:(1)in the experimental range,the pressure drop of parallel increases with the increase of high gravity factor and gas velocity,and decreases slightly with the increase of liquid spray density;The pressure drop of countercurrent increases with the decrease of high gravity factor and the increase of gas velocity,and slightly increases with the increase of liquid spray density.At low gas velocity,it has obvious advantages over parallel flow equipment.When the gas velocity is 2.36m/s and the high gravity factor is 45.25,the pressure drop of countercurrent dry bed is 3.03pa than that of parallel flow(2)When the gas-liquid countercurrent contact of RPB,with the increase of high gravity factor,there is a negative value of pressure drop.It can be used as a gas-phase transmission power equipment to reduce the investment in industrial application(3)The gas pressure drop of the rotating packed bed was considered by sections,and the model coefficients were fitted by experimental data.The pressure drop model is obtained as follows:ΔP并=5.345u2+3.19u0.16363β0.66898+0.0997β+0.00164β2-0.0361u0.37049β0.15313q1.52904+0.645(ui2-uo2)+0.3225u3→42δP逆=5.345u 2+2.656 u 2.20356β-0.1337-0.0997 β-0.00164β2+0.0161u1.07755β0.15313q.165291+0.645(ui2-uo2)+0.3225u1→02The calculated results are in good agreement with the experimental results.The average error of parallel flow pressure drop model is within±10%,and that of counter current is within±8%.The results of the model agree well with the experimental data,and can predict the pressure drop of the equipment(4)Through the CFD model simulation of the pressure drop of parallel and counter flow gas phase in rotating packed bed,it is found that there are obvious pressure drop and velocity gradient in the equipment.The pressure drop of the outer chamber is larger than that of the inlet and outlet and the pressure drop of the packing layer,and the velocity of the packing layer in the bed is the largest.In the parallel flow wet bed equipment,the gas inlet and the counter current wet bed equipment exit,the velocity field has a high side velocity and a low side velocity.The CFD simulation results are consistent with the experimental values,and the simulation calculation rules are consistent with the experimental valuesFigure 53 table 12 reference 93...