A modified internal-loop airlif reactor （MIALR） with a continuous slurry phase was studied to investigate the local hydrodynamic characteristics, including gas holdup, bubble size, bubble rise velocity and local mas...A modified internal-loop airlif reactor （MIALR） with a continuous slurry phase was studied to investigate the local hydrodynamic characteristics, including gas holdup, bubble size, bubble rise velocity and local mass transfer properties. Based on the analysis of geometrical construction and fluid properties of gas and slurry, MIALR was divided into six flow regions. In these flow regions, the local hydrodynamic characteristics were investigated over a wide range of operating variables. Furthermore, a new method was developed to measure the dissolved oxygen concentration. The volumetric mass-transfer coefficient in six flow regions was also calculated for comparison.展开更多
New modified combination mathematical models including the pores blocking models and the cake layer models were developed to describe the continuous cross-flow microfiltration in an airlift external loop slurry reacto...New modified combination mathematical models including the pores blocking models and the cake layer models were developed to describe the continuous cross-flow microfiltration in an airlift external loop slurry reactor. The pores blocking models were created based on the standard blocking law and the intermediate blocking law, and then the cake layer models were developed based on the hydrodynamic theory in which the calculation method of porosity of cake layer was newly corrected. The Air-Water-FCC equilibrium catalysts cold model experiment was used to verify the relevant models.Results showed that the calculated values fitted well with experimental data with a relative error of less than 10%.展开更多
以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位...以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位置的局部平均压力随气体流速的增大逐渐上升达到峰值后减小,峰值随着浸没比的减小而向右移动且上升速度增大;液体流速随着气体流速增大急剧上升达到峰值后几乎保持不变,最大提升效率约为49%,与最大液体流速并不发生在同一个气体流速下;在不同的气流量下,观测到气泡流、帽弹流、弹状流、搅拌流和环状流的出现,不同流型可通过PSD和PDF估计量进行识别;特别是,浸没比越小越有利于形成大气塞。目前,关于气举泵的研究非常有限,本研究结果可为气液固三相流和气液两相流的研究提供数据和技术支撑。展开更多
文摘A modified internal-loop airlif reactor （MIALR） with a continuous slurry phase was studied to investigate the local hydrodynamic characteristics, including gas holdup, bubble size, bubble rise velocity and local mass transfer properties. Based on the analysis of geometrical construction and fluid properties of gas and slurry, MIALR was divided into six flow regions. In these flow regions, the local hydrodynamic characteristics were investigated over a wide range of operating variables. Furthermore, a new method was developed to measure the dissolved oxygen concentration. The volumetric mass-transfer coefficient in six flow regions was also calculated for comparison.
基金financially supported by the National Key Research & Development Program of China (2016YFB0301600)
文摘New modified combination mathematical models including the pores blocking models and the cake layer models were developed to describe the continuous cross-flow microfiltration in an airlift external loop slurry reactor. The pores blocking models were created based on the standard blocking law and the intermediate blocking law, and then the cake layer models were developed based on the hydrodynamic theory in which the calculation method of porosity of cake layer was newly corrected. The Air-Water-FCC equilibrium catalysts cold model experiment was used to verify the relevant models.Results showed that the calculated values fitted well with experimental data with a relative error of less than 10%.
文摘以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位置的局部平均压力随气体流速的增大逐渐上升达到峰值后减小,峰值随着浸没比的减小而向右移动且上升速度增大;液体流速随着气体流速增大急剧上升达到峰值后几乎保持不变,最大提升效率约为49%,与最大液体流速并不发生在同一个气体流速下;在不同的气流量下,观测到气泡流、帽弹流、弹状流、搅拌流和环状流的出现,不同流型可通过PSD和PDF估计量进行识别;特别是,浸没比越小越有利于形成大气塞。目前,关于气举泵的研究非常有限,本研究结果可为气液固三相流和气液两相流的研究提供数据和技术支撑。
