Gas - Liquid - Solid Reactors

Microstructured Devices for Chemical Processing, First Edition. 

Madhvanand N. Kashid, Albert Renken and Lioubov Kiwi-Minsker. 

Fluidized bed Good heat and mass transfer Good performance in the limited 

Slurry reactor Effective utilization of catal t Good liquid—solid mass transfer Good heat transfer Moderate gpas—liquid mass transfer Catalyst separation is difficult and a filtration step is required Low conversion and selectivity in continuous mode following backmixing 

Catalytic wall Effective utilization of catalyst Heat/nmss transfer limits the 

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Andersson, B. (2003) Important factors in bubble coalescence modeling in stirred tank reactors. 6th International Conference on Gas liquid and Gas-Liquid -Solid Reactor Engineering, 2003, Vancouver. 

Our very first experiments with the reactor depicted in Figure 5.4.1 were carried out with a 15% Pt-Y-Al203 single cylindrical catalyst pellet [10-12], The acquisition time of 2D images of an axial slice at that time was about 260 s. Despite this, the first direct MRI visualization of the operation of a model gas-liquid-solid reactor has revealed the existence of large gradients of the liquid phase content within the catalyst pellet upon imbibition of liquid a-methylstyrene (AMS) under conditions... 

Shah, Y. T., Gas-Liquid-Solid Reactor Design, McGraw-Hill, New York, (1979)... 

Tarmy, B. L., and Coulaloglou, C. A., Alpha-Omega and Beyond - Industrial View of Gas/Liquid/Solid Reactor Development, Chem. Eng. Sci., 47 3231 (1992)... 

Reflux ratio R 0.5 2 Type Gas Liquid Solid Reactor ... 

A trickle-bed reactor is a three-phase (gas + liquid + solid) reactor in which the solid... 

Describe the various mass transfer and reaction steps involved in a three-phase gas-liquid-solid reactor. Derive an expression for the overall rate of a catalytic hydrogenation process where the reaction is pseudo first-order with respect to the hydrogen with a rate constant k (based on unit volume of catalyst particles). 

Agitated slurry reactor (ASR) This is a mechanically agitated gas-liquid-solid reactor (Figure 3.13). The liquid is agitated by a mechanical apparatus (impeller). The fine solid particles are suspended in the liquid phase by means of agitation. Gas is sparged into the liquid phase, entering at the bottom of the tank, normally just under the impeller. This reactor can also be of continuous type or of semibatch type. This type is used only in catalysis. 

The second section presents a review of studies concerning counter-currently and co-currently down-flow conditions in fixed bed gas-liquid-solid reactors operating at elevated pressures. The various consequences induced by the presence of elevated pressures are detailed for Trickle Bed Reactors (TBR). Hydrodynamic parameters including flow regimes, two-phase pressure drop and liquid hold-up are examined. The scarce mass transfer data such gas-liquid interfacial area, liquid-side and gas-side mass transfer coefficients are reported. 

Hydrodynamics and mass transfer in fixed-bed gas-liquid-solid reactors operating at high pressure... 

A fundamental division of multiphase reactors may be made, depending on whether the solid phase is present as a moving-or as a fixed bed. In principle, one gas-liquid-solid reactor with the fixed bed of solids can be operated in three ways, depending upon the relative orientation of the superficial gas-mass G and superficial liquid-mass L flow-rates (see Figure 5.2-1). 

Concurrent flow of liquid and gas can be simulated by the homogeneous model of Section 6.8.1 and Eqs. 6.109 or 6.112, but several adequate correlations of separated flows in terms of Lockhart-Martinelli parameters of pipeline flow type are available. A number of them is cited by Shah (Gas-Liquid-Solid Reactor Design, McGraw-Hill, New York, 1979, p. 184). The correlation of Sato (1973) is shown on Figure 6.9 and is represented by either... 

GAS - LIQUID - SOLID REACTORS FOR HYDROGENATION IN FINE CHEMICALS SYNTHESIS... 

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