Studies On Gas Pressure Drop And Mass Transfer Performance In A Rotating Packed Bed With Structured Packing

Since the structured packing has many advantages, such as low gas pressure drop and liquid hold, high efficiency of separation, it has been developed rapidly. Nowadays, the structured packing has already been used in RPB, however there is few liturature that the structured packing which formed by stainless steel wire mesh used in the new equipment of process intensification-the Rotating Packed Bed(RPB). RPB can be regard as the key part of Higee technology. RPB relay on the rotational rotor to simulate a high gravity environment which can spread the liquid into thin film and tiny droplets. Thereforethe high surface renewal rate and excellent mass transfert and the micro-mixing efficiency can be demonstrated in a RPB.In this paper, the advantages of low gas pressure and high separation efficiency of structured packing were combined with the high mass transfer efficiency of a RPB. And it was expected to get a lower gas pressure drop and lose mass transfer efficiency as little as possible.The air-water system was used to investigate the gas pressure drop in RPB with structured packings. The effects of rotational speed, gas flow rate and liquid flow rate on the gas pressure drop was studied. The experimental results indicated that the dry and wet bed pressure drop increased with the increase of rotational speed and gas flow rate. The change of liquid flow rate has little influence on the wet bed pressure drop. Compared with the pressure drop in the RPB with mesh packing, was decresed by50-70%in the one with structured packings. Based on the experimental data, correlation of wet bed pressure drop was proposed. The deviation between the calculated and experimental value of wet bed pressure drop was within±15%.The mass transfer performance of the RPB with structured packing was studied by empolying chemisorption of CO2into a NaOH solution. The effective interfacial area(aP and ac) and the liquid side mass transfer coefficient(kLaP and kLac) of packing and cavity zone were inveatigated, respectively.. With the increase of rotational speed, gas flow rate and liquid flow rate, the aP, ac and the kLaP, kLac increased in the both packing and cavity zone. Comparison of aP of different kind of structured packing, the thinner fiber diameter, the larger pore diameter and corrugation angle provided the larger aP when other parameters of the structured packing were identical. For all of the four structured packing, the overall effective mass transfer surface area A in RPB was presented by packing and cavity zone, and the percentage for these two zones was equal to91%and9%, respectively. The efficiency of the effective interfacial area of Packing D’s(d=0.6mm,φ=4mm,β=90°) is75.8%, which is the highest among the four structured packings. Finally, the desulfurization performance of RPB equipped with the Packing D was investigated. The results indicated that the SO2removal efficiency increased with the increasing of rotational speed and the (NH4)2SO3concentration, decreased with the increasing of the SO2inlet concentration and the gas-liquid ratio.