Studies Of Mass Transfer And Desulfurization Application In A Rotating Packed Bed With Novel Combined Rotors

Rotating packed bed (RPB), is a novel reactor strengthening the chemical industry process. The RPB reactor simulates a higee circumstance with centrifugal force, cutting the liquid with high dispersion, improving the renewal frequency of liquid surface, causing the high mass transfer performance. Owing to this, RPBs are usually applied for industry process such as distillation and absorption process. The main structure of RPB has been formed and the internals become the core of further development, such as innovative design of the rotors and optimization design of the liquid distributors.Packings in the reactors tend to be blocked by the solid particles producted and the dust following with gas flow, in some chemical industry process. Rotor in the RPB used to be loaded with wire mesh packing, the pore diameter of the packing is smaller, and the space between layers is closer. Thus, the solid particles tend to stack in the wire mesh packings, blocking the path of gas-liquid flow, weakening the mass transfer performance and even halting the machine to be cleaned, which could influence the productive process and increase the cost for cleaning equipment. To solve those problems, we design novel combined rotors with different structures in the radial direction based on the research efore. The main study details is as follows:1. To ensure the mass transfer performance, we need to design a novel rotor which could prevent blockage. The absorption of CO2 in NaOH solution is selected to study the liquid mass transfer performance changing the rotational speed, liquid flow rate and gas flow rate in this work. The results indicate that ae and kLae increased with the increasing of rotational speed, liquid flow rate, and gas flow rate, respectively. The more proportion of wire mesh packing, the higher mass transfer performance is achieved.2. To establish the liquid mass transfer model, the rotor zone is devided into packing zone and pillar zone in this work. Based on the theory of surface renewed, ?L is an important parameter to establish a model. Thus, X-ray CT scan technology is applied to study the ?L in the pillar zone, which could also provide visualization methods to explore the liquid flow patterns in the rotors. The results indicate that ?L decreased with the increasing of rotational speed and increased with the increasing of liquid flow; ?L in the pillar zone is higher than that of in the packing zone and the maldistribution of liquid is obvious in the packing zone. According to the data, we establish the correlations of ?L in the pillar zone. Finally, the correlations are brought into the model which can be seen that the kLae calculated from the model is within ±15% of the experimental data.3. Based on the research before, mass transfer performance of rotor 2 which is expected to prevent blockage with sacrificing a small amount of mass transfer performance is approaching to that of the rotor 3. Thus, rotor 2 and rotor 3 are selected to study the desulfurization performance by gypsum method. The results indicated that the absorbtion efficiency of SO2 increased with the increasing of rotational speed, decreased with the increasing of inlet SO2 concentration and gas-liquid ratio. And the absorbtion efficiency of SO2 with in RPB with rotor 3 is little higher than that with rotor 2.