The development and modelling of high-intensity impinging stream jet reactors for effective mass transfer in heterogeneous systems
Date
1999
Authors
Kleingeld A.W.
Lorenzen L.
Botes F.G.
Journal Title
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Abstract
A novel type of phase-contacting device has been researched and is currently being developed at this institution. These high-intensity jet reactors provide significant improvement over conventional phase-contacting equipment due to the impingement of high-velocity feed streams upon each other in relatively small reactor volumes, resulting in a highly turbulent mixing of phases. Due to this intimate contact between phases, mass transfer coefficients (k(L)) of up to 1.5 x 10-3 m/s have been realised, which, coupled with values of the specific interfacial area (a) of 8-18 000 m2/m3, have yielded volumetric mass transfer coefficients (k(L)a) of up to 22 s-1 which are orders of magnitude higher than typical values obtained by conventional systems. A model for the prediction of the interfacial area production in these new reactors has also been proposed. It is implemented in the form of a Monte Carlo simulation, based on the fact that bubble breakup in a turbulent environment is governed by the interactions of bubbles with turbulent eddies. Although the model is only a first attempt, it has proved to be highly practical and flexible, reasonably predicting trends in the experimental data.A novel type of phase-contacting device has been researched and is currently being developed at this institution. These high-intensity jet reactors provide significant improvement over conventional phase-contacting equipment due to the impingement of high-velocity feed streams upon each other in relatively small reactor volumes, resulting in a highly turbulent mixing of phases. Due to this intimate contact between phases, mass transfer coefficients (kL) of up to 1.5 × 10-3 m/s have been realised, which, coupled with values of the specific interfacial area (a) of 8-18 000 m2/m3, have yielded volumetric mass transfer coefficients (kLa) of up to 22 s-1 which are orders of magnitude higher than typical values obtained by conventional systems. A model for the prediction of the interfacial area production in these new reactors has also been proposed. It is implemented in the form of a Monte Carlo simulation, based on the fact that bubble breakup in a turbulent environment is governed by the interactions of bubbles with turbulent eddies. Although the model is only a first attempt, it has proved to be highly practical and flexible, reasonably predicting trends in the experimental data.
Description
Keywords
Bubbles (in fluids), Carbon dioxide, Computer simulation, Gas absorption, Jets, Mass transfer, Monte Carlo methods, Turbulent flow, Bubble breakup, Impinging stream jet, Mass transfer coefficient, Bubble columns, jet impingement, mass transfer, Monte Carlo simulation, reactor
Citation
Chemical Engineering Science
54
21
54
21