Flow and dispersion performance of gas/ionic liquid systems in microchannels

doi:10.3969/j.issn.0438-1157.2014.01.007

Abstract

Abstract: Ionic liquids show good prospect in gas-liquid reaction and separation processes. Investigation of flow and dispersion performance of gas/ionic liquid systems is important for the development of technology and devices for gas-liquid dispersion as well as application of ionic liquids in gas-liquid reaction and separation processes. The flow and dispersion performance of N₂/[Bmim]BF₄ in coaxial annular microchannels was investigated. Flow patterns of bubble-flow, bubble-slug-transition-flow, slug-flow and slug-annular-transition-flow were observed. The influence of gas and liquid flow rates on gas-liquid flow pattern was studied in different microchannels and flow pattern maps were determined accordingly. The effects of gas and liquid flow rates on dispersion size were also investigated. The mechanism was discussed and mathematical models were established to predict the dispersion size in different microchannels.

Key words: microchannel, gas-liquid system, ionic liquids, dispersion

摘要： 离子液体在气-液反应与分离过程中有良好的应用前景，研究气体/离子液体两相体系的微分散过程对于发展新型气-液分散技术和设备具有重要意义。研究了N₂/[Bmim]BF₄体系在同轴环管微通道中的流动和分散行为。实验结果表明，在不同的气相和液相流速下，N₂/[Bmim]BF₄体系分别呈现气泡流、气泡-气柱过渡流、气柱流和气柱-环隙流过渡流4种流型。通过考察分散相尖端尺寸和气相、液相流速对气-液体系流型的影响，作出了相应的流型图。通过考察气相、液相流速对稳定气-液分散流型下的气相分散尺寸的影响，揭示了分散气相行为的机理，并建立了描述气相分散尺寸的数学模型。

关键词: 微通道, 气-液体系, 离子液体, 分散

CLC Number:

TQ021.4

TAN Jing, ZHAO Jingjing, XU Jianhong, LUO Guangsheng. Flow and dispersion performance of gas/ionic liquid systems in microchannels[J]. CIESC Journal, 2014, 65(1): 55-60.

谭璟, 赵菁菁, 徐建鸿, 骆广生. 微通道中气体/离子液体两相流动与分散性能[J]. 化工学报, 2014, 65(1): 55-60.

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