Studies On Performance Of A Wholly Rotating Zigzag Bed

Because of relatively high power consumption of rotating zigzag bed?RZB?,a new kind rotating zigzag bed?n RZB?with rotating both upper and lower discs was developed.First,ethanol-water system was used to investigate its mass transfer per-formance.The effects of F-factor and rotor speed on theoretical plate were studied.And radial blades were installed at inner edge of rotor to research the effect of liquid initial distributions on mass transfer.Second,air-water system was adopted to study pressure drop.The dependence of pressure drop on superficial gas velocity,liquid spray density and rotor speed was analyzed.Models for dry and wet bed pressure drop were established,Third,the power consumption was also studied by air-water system.The variation of liquid power consumption with liquid flowrate and rotor speed were discussed.A model for liquid power consumption was also established.Finally,n RZB was comprehensively compared with RZB.Results of mass transfer experiments were showed as follows.The number of theoretical plates increased with the increase of F-factor,and decreased with the increase of rotor speed for lower F-factor.With a higher F-factor,the increase of rotor speed first increased and then decreased the number of theoretical plates.The rotor with blades at the inner side showed a greater flux and better mass transfer perfor-mance.When rotor speed was 900 r·min^-1and F-factor was 41 kg^0.5·m^-0.5·s^-1,the rotor with radial blades at inner edge has 3.82 theoretical plates,equivalent to 17 theoretical plates per meter based on the radial thickness of rotor.Results of pressure drop experiments were given in the following.Both dry and wet bed pressure drop increased with the increase of superficial gas velocity and rotor speed.Wet bed pressure drop decreased first and then increased with the increase of liquid spray density.Wet bed pressure drop was smaller than dry bed pressure drop.Moreover,the flooding velocity increased with the increase of liquid spray density,and decreased with the increase of rotor speed.The average relative deviations bet-ween experimental and calculated values of dry and wet bed pressure drop were 2.3%and 3.4%,respectively.Results of power consumption experiments were presented below.The liquid power consumption increased approximately linearly with the increase of liquid flowrate and rotor speed squared.Besides,the average relative deviation between experimental and calculated liquid power consumption was 5.3%.Effect of gas on power consumption was small.Finally,compared with RZB,the number of theoretical plate of n RZB was redu-ced by about 60%,liquid power consumption of n RZB was reduced by 65%?75%,and liquid power consumption per theoretical plate of n RZB was reduced by about35%.The pressure drop of n RZB was similar to that of RZB at the same operating conditions.