| Mass transfer efficiency and hydrodynamic performance are two importantindicators of the extraction equipment, how to strengthen the extraction process is animportant research direction of extraction process. In this paper, we firstly determinedthe effect of gas disturbance to liquid-liquid extraction in different packing, and then anovel structured packing with diversion windows and a novel liquid-liquid loopdevice were designed based on the principles of jet loop contactor and droplet-filmalternate flow.Firstly, in gas-liquid-liquid system, the flow patterns of the droplets wereobserved, and the hydrodynamics performance and mass transfer efficiency ofdifferent packing were measured. The experimental results showed that gas hold-upand liquid hold-up increases with an increase in gas velocity. The apparent height ofmass transfer unit decreased significantly with the air disturbance.Secondly, for liquid-liquid extraction, a novel structured packing with diversionwindows was developed. The geometry characteristic of the proposed structuredpacking is the diversion windows arranged in the crest and trough of the traditionalripple packing. Due to the division windows on the structured packing, the flowpattern was adjusted, that is, the liquid stream on one side of packing can penetratethrough the windows and then reach to the other side of the packing. In addition, theflow channel for the gas phase was enlarged and the disturbance frequency wasincreased. The mass transfer efficiency and hydrodynamic performance of the novelpacking was determined experimentally. The results indicate that along with theincrease in gas phase flow rate, the flooding velocity decreases, and the apparentheight of mass transfer unit first reduces but then increases. The proposed structuredpacking can promote the dispersed phase’s droplet-film flow pattern, thus helpedenhancing the mass transfer. For the same operating conditions, the hydrodynamicperformance and mass transfer efficiency of the novel structured packing can beincreased by11%and44.7%than that of Super Mini Ring packing in average.Thirdly, based on the principles of jet loop contactor and droplet-film alternateflow, a novel liquid-liquid loop device was designed in the present paper. Due to theideal flow pattern for dispersed phase and continuous phase in the device, thefrequency of droplet breakage and coalescence in dispersed phase was increased. Theexperiments were carried out to verify the performance of the apparatus inliquid-liquid extraction. Compared with Super Mini Ring packing extraction tower, the hydrodynamic performance in the novel device can be increased by50%and masstransfer efficiency can be increased by25%in average. |
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