The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of ma...The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of macromixing time and micromixing time are quantitatively discussed. The results show that under a continuous and stable operating condition, as the paddle speed increases, the macromixing time and micromixing time calculated by the two models both decrease, even in a linkage equilibrium state. Simultaneously, as the paddle speed increases, the results figured by the two models tend to be consistent. It indicates that two models both are more suitable for calculation of mixing time in high paddle speed. Compared with the existing experimental results of this type of reactor, the mixing time computed in the speed of 1500 r/min is closer to it. These conclusions can provide an important reference for systematically studying the strengthening mechanism of LISR under continuous mixing conditions.展开更多
Based on some experimental investigations of liquid phase residence time distribution(RTD)in an impinging stream reactor,a two-dimensional plug-flow dispersion model for predicting the liquid phase RTD in the reactor ...Based on some experimental investigations of liquid phase residence time distribution(RTD)in an impinging stream reactor,a two-dimensional plug-flow dispersion model for predicting the liquid phase RTD in the reactor was proposed.The calculation results of the model can be in good agreement with the experimental RTD under different operating conditions.The axial liquid dispersion coefficient increases monotonously with the increasing liquid flux,but is almost independent of gas flux.As the liquid flux and the gas flux increase,the liquid dispersion coefficient of center-to-wall decreases.The axial liquid dispersion coefficient is much larger than that of center-to-wall,which indicates that the liquid RTD is dominated mainly by axial liquid dispersion in the impinging stream reactor.展开更多
This paper presents an experimental investiga-tion of a novel impinging stream reactor(ISR)with the aim of high mixing intensity.The integral mixing quality in the reactor was measured with the iodide-iodate reaction ...This paper presents an experimental investiga-tion of a novel impinging stream reactor(ISR)with the aim of high mixing intensity.The integral mixing quality in the reactor was measured with the iodide-iodate reaction and showed excellent mixing performance.The impact of the operating parameters,such asfluxes,circulation and inter-nozzle distances,was investigated in terms of segregation index.The results showed that the increase offlux,the decrease of inter-nozzle distance and a suitable circulation can improve the micro-mixing efficiency.Based on turbulence theory,it was estimated that the characteristic micro-mixing time was 0.002–0.02 s,which was much shorter than that in the stirred tank reactor.The micro-mixing time was related to the segregation index,which was in good agreement with those in the literature.展开更多
基金Project(51276131)supported by the National Natural Science Foundation of ChinaProject(ZRZ0316)supported by the Natural Science Foundation of Hubei Province,ChinaProject(2013070104010025)supported by the Morning Glory Project of Wuhan Science and Technology Bureau,China
文摘The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of macromixing time and micromixing time are quantitatively discussed. The results show that under a continuous and stable operating condition, as the paddle speed increases, the macromixing time and micromixing time calculated by the two models both decrease, even in a linkage equilibrium state. Simultaneously, as the paddle speed increases, the results figured by the two models tend to be consistent. It indicates that two models both are more suitable for calculation of mixing time in high paddle speed. Compared with the existing experimental results of this type of reactor, the mixing time computed in the speed of 1500 r/min is closer to it. These conclusions can provide an important reference for systematically studying the strengthening mechanism of LISR under continuous mixing conditions.
基金supported financially by the National Basic Research Program of China(No.2004CB217703)New Century Excellent Talents in University(NCET-05-0413).
文摘Based on some experimental investigations of liquid phase residence time distribution(RTD)in an impinging stream reactor,a two-dimensional plug-flow dispersion model for predicting the liquid phase RTD in the reactor was proposed.The calculation results of the model can be in good agreement with the experimental RTD under different operating conditions.The axial liquid dispersion coefficient increases monotonously with the increasing liquid flux,but is almost independent of gas flux.As the liquid flux and the gas flux increase,the liquid dispersion coefficient of center-to-wall decreases.The axial liquid dispersion coefficient is much larger than that of center-to-wall,which indicates that the liquid RTD is dominated mainly by axial liquid dispersion in the impinging stream reactor.
文摘This paper presents an experimental investiga-tion of a novel impinging stream reactor(ISR)with the aim of high mixing intensity.The integral mixing quality in the reactor was measured with the iodide-iodate reaction and showed excellent mixing performance.The impact of the operating parameters,such asfluxes,circulation and inter-nozzle distances,was investigated in terms of segregation index.The results showed that the increase offlux,the decrease of inter-nozzle distance and a suitable circulation can improve the micro-mixing efficiency.Based on turbulence theory,it was estimated that the characteristic micro-mixing time was 0.002–0.02 s,which was much shorter than that in the stirred tank reactor.The micro-mixing time was related to the segregation index,which was in good agreement with those in the literature.
