Mixing in milli torus reactor under aerated conditions

• Published in: Chemical engineering and processing Vol. 48; no. 5; pp. 1012 - 1019
• Main Authors: Rihani, R., Legrand, J., Bensmaili, A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 2009; Elsevier
• Subjects: Aerated conditions; Applied sciences; Axial dispersion coefficient; Chemical engineering; Exact sciences and technology; Gas hold up; Hydrodynamics of contact apparatus; Milli torus reactor; Mixing; Reactors; Mixing; Milli torus reactor; Gas hold up; Axial dispersion coefficient; Aerated conditions; Correlation; Particle size; Rotation speed; Axial mixing; Agitator; Modeling; Aeration; Bubble; Flow regime; Reactor; Gas holdup; Two phase flow; Homogenization; Hydrodynamics; Recirculation; Flow field; Plug flow; Correlation analysis; Coalescence; Tracers
• ISSN: 0255-2701; 1873-3204
• DOI: 10.1016/j.cep.2009.01.009

The present paper contributes to improve the understanding of two-phase flow hydrodynamics characteristics in milli torus reactor. To reach this goal, experiments were performed in a vertical milli torus reactor, having a capacity of 0.140 l. The effect of the aeration numbers and the impeller rotation speeds has been studied. It was found that the homogenization of the tracer inside the gas–liquid milli torus reactor was nearly achieved after more recirculations than those obtained in one-phase flow. Under aerated conditions, the flow pattern depended on both impeller rotation speeds and aeration numbers. Two flow regimes have been distinguished: not-dispersed and dispersed flow regimes. The flow induced by a rotating marine impeller reduced bubble size and prevented bubbles coalescence for aeration numbers Fl > 0.0021, at which the dispersed flow regime can be maintained in the milli torus reactor. The flow behaviour inside the milli torus reactor was modelled by the dispersed plug flow model. Correlations have been proposed to predict gas hold up and axial dispersion.