Mass transfer and hydrodynamic characteristics of a Long Draft Tube Self-ingesting Reactor (LDTSR) for gas-liquid-solid operations

Abstract

Gas-liquid stirred vessels are widely employed to carry out chemical reactions involving a gas reagent and a liquid phase. The usual way for introducing the gas stream into the liquid phase is through suitable distributors placed below the impeller. An interesting alternative is that of using “self ingesting” vessels where the headspace gas phase is injected and dispersed into the vessel through suitable surface vortices. In this work the performance of a Long Draft Tube Self-ingesting Reactor dealing with gas-liquid-solid systems, is investigated. Preliminary experimental results on the effectiveness of this contactor for particle suspension and gas-liquid mass transfer performance in presence of solid particles are presented. It is found that the presence of low particle fractions causes a significant increase in the minimum speed required for vortex ingestion of the gas. Impeller pumping capacity and gas-liquid mass transfer coefficient are found to be affected by the presence of solid particles, though to a lesser extent than with other self-ingesting devices.