Chum turbulent bubble columns

Myers, K. J. (1986) Liquid-Phase Mixing in Chum-Turbulent Bubble Columns, D. 

Myers, K. J., Dudukovic, M. P. and Ramachandran, P. A. (1987) Modeling of Chum-Turbulent Bubble Columns-I Liquid Phase Mixing, Chem. Eng. Sci. 42,2301-2311. 

Figure 5.3-8. Details of the chum-turbulent flow regime of BSCR according to Inga [1], (db)0-gas bubble size at atmospheric conditions in the absence of solid particles, (d, )ps- bubble size at the operating pressure and catalyst concentration. Column height = 2.8 m, internal diameter = 0.316 m. P < 8 bars. Organic media, catalyst diameter < 100 pm.

Krishna R, Urseanu MI, van Baten JM, Ellenberger J. Influence of scale on the hydrodynamics of bubble columns operating in the chum-turbulent regime experiments vs. Eulerian simulations. Chem Eng Sci 1999 54 4903 -911. 

Axial mixing in the liquid, induced by the upflow of the gas bubbles, can be substantial in commercial-scale bubble columns, especially in the chum turbulent regime. Due to typically small particle size, the axial dispersion of the solid catalyst in slurry bubble columns is expected to follow closely that of the liquid exceptions are high-density particles. The liquid axial mixing can be represented by an axial dispersion coefficient, which typically has the form... 

Of interest is a recent theoretical relation for eg in gas-liquid bubble columns based on liquid circulation and claimed to be valid both in the homogeneous bubble flow regime and in the chum-turbulent regime, also for non-Newtonian fluids. For power law fluids with... 

Figure 5 gives a few examples from Kara et al. [70] together with two correlations. Recent experiments with a large-scale slurry bubbling column (dc = 0.57 m, H = 7.62 m) operating in the chum-turbulent regime, revealed that the liquid phase could be considered as ideally mixed [71],... 

Bubble columns Loop reactors Stirred tanks Hydrocyclones Reasonable Reasonable Reasonable Reasonable Modeling of chum-turbulent flow regime Modeling of chum-turbulent flow regime Improved geometrical representation of impeller and baffles Improved geometrical representation of system... 

CFD approach. This model has too many unknown parameters when applied to multiphase flow. The kind of model used by Dudukovic group (72) computed the Reynolds stresses in agreement with measurements done in L.S. Fan s laboratory. In the Matonis et al (75) paper we show our capability to compute turbulence in a slurry bubble column in the chum-turbulent regime in agreement with our measurements. 

Krishna R, Baten JMV, Urseanu MI Three-phase Eulerian simulations of bubble column reactors operating in the chum-turbulent regime a scale up strategy, Chem Eng Sci 55(16) 3275-3286, 2000. 

The CARPT—CT techniques have been introduced at CREL to provide cold flow modeling information on slurry bubble column flows operated in chum turbulent regime needed for gas-to-Hquid conversion processes (Degaleesan, 1997 Degaleesan and Dudukovic, 1998 Degaleesan et al.. 

The concentrations of A are gas phase concentrations. This applies particularly to the homogeneous regime, but with reasonable accuracy to the chum>turbulent regime as well. The consequence is, that when the above proportionalities apply, the performance of the bubble column as an absorber would be independent of the gas load. 

Vermeer, D. J. and Krishna, R. (1981) Hydrodynamics and Mass Transfer in Bubble Columns Operating in the Chum Turbulent Regime, Ind. Eng. Chem. Process. Des. Develop. 20,475-482. 

Antal SP, Lahey Jr RT, Al-Dahhan MH (2004) Simulating Chum-Turbulent flows in a bubble column using a three field, two-fluid model. Paper presented at the 5th international conference on multiphase flow, ICMF 04, Yokohama, Japan, 30 May-4 June, p 182... 

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