Population balance simulation of gas–liquid contacting

Turbulently flowing liquid–liquid dispersions. Part I: Drop breakage and coalescence

“…The resulting equations are often partial integrodifferential equations with integral boundary conditions that rarely admit analytical solutions, therefore the use of numerical techniques is necessary for obtaining a solution [26][27][28]. Consequently, the method of discretization of the continuous PBE has emerged as an attractive alternative to the various other numerical methods of solutions [29][30][31] and has been successfully employed, starting with the work of [32], to render accurate numerical solutions of the PBE [16,[33][34][35].…”

Hydrodynamics of Liquid Flow Through Screens and Screen-Type Static Mixers

“…Recently, a new type of static mixing element was introduced in which screens or grids are used to repetitively superimpose an adjustable uniformly distributed turbulence field on the nearly plug flow conditions encountered in high velocity pipe flows. This characteristic made them particularly effective in processing multiphase systems (Al Taweel and Chen, 1996;Azizi and Al Taweel, 2007). Moreover, the very high turbulence intensities generated in the regions adjacent to the screens resulted not only in the formation of fine dispersed phase entities (bubbles and=or drops) but also considerably enhanced the value of the interphase mass transfer coefficient (Al Taweel et al, 2005.…”

“…Moreover, the very high turbulence intensities generated in the regions adjacent to the screens resulted not only in the formation of fine dispersed phase entities (bubbles and=or drops) but also considerably enhanced the value of the interphase mass transfer coefficient (Al Taweel et al, 2005. The relatively uniform energy dissipation rates prevalent in the downstream regions behind screens offer ideal conditions for investigating bubble and drop breakup and coalescence under turbulent conditions and the assessment=screening of the various models proposed for such processes (Azizi and Al Taweel, 2007). In addition, the quasi-isotropic turbulence generated by grids was taken advantage of to study the effect of turbulent mixing on the evolution of chemical reactions (Bennani et al, 1985) and served as a medium for testing the applicability of micromixing models (Bourne and Lips, 1991).…”

Effect of Mixing on Microorganism Growth in Loop Bioreactors

“…The effectiveness of this redistribution is a function of the specific design and number of elements. On the other hand, the recently introduced screen/grid mixing elements can be considered as means for modifying the turbulent characteristics (turbulence scales and intensity) of the pipe flow, thereby providing a high degree of control on the performance of the gas/liquid contact [20,29,30].…”