Effect of Stator Geometry on the Emulsification and Extraction in the Inline Single-Row Blade-Screen High Shear Mixer

Abstract

A series of stators were designed with the same opening area but different opening shape and number for the inline single-row blade-screen high shear mixers (HSMs), to study the emulsification and extraction, respectively. The opening number has a significant influence on the emulsification and extraction, as compared to the opening shape. The computational fluid dynamics (CFD) analysis was used to disclose the intensifying rules of HSMs with desirable stator geometry. In the rotor and screen region, both energy dissipation rate and shear stress increase first but then decrease as the opening number rises, whereas in the jet region both of them decrease with the opening number. The opening number can affect the flux through screen and shear gap, as well as the reentrainment and jet behaviors in the screen region. These results provide important guidance on the design and optimization of HSMs structures to intensify the emulsification and extraction.

Generation of Bulk Nanobubbles Using a High-Shear Rotor–Stator Device

“…However, this is not the case for SCS, which suggests that this is a simplistic interpretation of the complex phenomena occurring in the high-shear region of the device, which lead to the formation of BNBs. Some earlier studies mainly targeted at the process of emulsification investigated the complex flow field generated by different rotor–stator configurations via experimental measurements and computational fluid mechanics simulations in some detail. − It ensures that there are other important parameters that influence the flow field in the vicinity of the rotor–stator such as the shape and size of the openings, their spacing, and stator thickness, in addition to operational parameters including rotor speed, energy input, liquid physical properties, and the onset of hydrodynamic cavitation.…”

Liquid–Liquid Dispersion and Selectivity of Chemical Reactions in the Inline Teethed High Shear Mixers

“…To deeply understand the effects of structural parameters on the mass transfer performance in the HSMs, the flow fields were simulated by ANSYS Fluent. As the volume fraction of the organic phase is only 1%, the single-phase simulation method can effectively predict the flow characteristics to simplify the calculations for this work. The simulations were calculated by the standard k -ε model along with enhanced wall function, which was widely applied to predict the flow characteristics in batch and inline HSMs. − The multiple reference frame method was applied to simulate the transient motion between the rotor and stator. , The inlet and outlet were set as the velocity inlet and pressure outlet, respectively.…”

“…The average energy dissipation rates ε in the mixers can be estimated by eq , where V denotes the total volume of the fluid in the chamber.…”

“…13 Inline HSMs, with characteristics of continuous operation, high capacity, and short residence time, are widely applied in intensifying the multiphase mass transfer processes. 9,14,15 Inline HSMs generally consist of two types: blade-screen and rotorstator teethed configurations. Shi et al 9 compared the gas− liquid mass transfer efficiency of the blade-screen and ultrafineteethed inline HSMs; the results indicated that the ultrafineteethed HSM was more efficient owing to the larger dissipation rates, less channeling, and short pass.…”

“…High shear mixers (HSMs), with advantages of narrow shear gaps, high rotor tip velocity, high shear rates as well as large energy dissipation rates, are widely employed in intensifying processes such as liquid–liquid emulsification, , gas–liquid mass transfer, solid–liquid suspension, and chemical reactions, especially some fast or instantaneous reactions. , For multiphase reactions, such as liquid–liquid systems, mass transfer efficiency can be improved because of the comparatively large interface areas generated by high shear mixing . Inline HSMs, with characteristics of continuous operation, high capacity, and short residence time, are widely applied in intensifying the multiphase mass transfer processes. ,, Inline HSMs generally consist of two types: blade-screen and rotor-stator teethed configurations. Shi et al compared the gas–liquid mass transfer efficiency of the blade-screen and ultrafine-teethed inline HSMs; the results indicated that the ultrafine-teethed HSM was more efficient owing to the larger dissipation rates, less channeling, and short pass.…”