Hydrodynamics and heat transfer of rheologically complex fluids in a Sulzer SMX static mixer

Abstract

In-line static mixers are widely used in continuous mixing, heat and mass transfer processes and chemical reactions. However, a good grasp of the hydrodynamics and heat transfer is still missing when rheologically complex fluids are involved. This paper presents a study of the hydrodynamics through Residence Time Distribution (RTD) determination and pressure drop, heat transfer and mixing mechanism in a Sulzer SMX static with both Newtonian and rheologically complex fluids. A RTD model and a correlation of friction fanning factor f/2 are proposed to explain the flow pattern inside the mixer. A general heat transfer coefficient correlation shows an enhancement of a factor about 5 with respect to an empty tube. The state-of-the-art chaos analysis applied to the temporary measurements of resistivity or temperature demonstrates that the mixing mechanism is chaotic in the Sulzer mixer.