Slurry column flow regimes

Flow regimes in slurry bubble column reactors... 

The hydrodynamics of bubble columns and slurry bubble column reactors depend strongly on the flow regime (Figure 3.27). There are three flow patterns that prevail in these reactors (Wallis, 1969 Shall et al., 1982) ... 

Suppose that the reaction takes place in a slurry bubble column and that it is desirable to work in the heterogeneous flow regime. Moreover, assume that the liquid is batch and well mixed and the flow of the gas approximates the ideal plug flow. 

Figure 5.3-7. Scheme of the flow regimes in bubble slurry column [6]. 

A bubble column is a contactor which involves the passage of a discontinuous gas phase in the form of bubbles, through a continuous phase, which can either be a liquid or a homogeneous slurry. The various flow regimes that can occur in a bubble column have been characterized by Shah et al. (1). The bubbly flow regime occurs for low superficial gas velocities (< 0.05 m/s), and is distinguished by bubbles of uniform... 

Figure 17.7 Flow regimes and transition gas velocities in a bubble column slurry reactor (adapted from Shah et al., 1982).

Vandu CO, Krishna R. (2004) Volumetric mass transfer coefficients in slurry bubble columns operating in the churn-turbulent flow regime. Chem. Eng. Process., 43 987-995. 

Figure 12.21 Hydrodynamic model of a slurry bubble column reactor in the heterogeneous flow regime [82]. (Source van der Laan [82]. Reproduced with permission of Elsevier.)...

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.. 

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. 

Van der Laan [82] reported attempts to model FT in a bubble column reactor. His model exhibited well-mixed liquid and two gas bubble regimes small bubbles that were well mixed and large bubbles that showed plug flow behavior (Figure 12.21). Van der Laan [82] also provided a summary of bubble column reactor models that others have utilized (Tables 12.1 and 12.2). He concluded that the FT slurry bubble column reactor is reaction controlled due to the low activity of the iron catalyst and the... 

Controlling regimes in an MASR Bubble column slurry reactors Regimes of flow Mass transfer... 

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