Mass transfer/mixing

Heat, mass transfer, mixing Water hammer... 

Finally, i should be noted that the calculation of the power requirement requires a knowledge of the impeller speed which is necessary to blend the contents of a tank in a given time, or of the impeller speed required to achieve a given mass transfer rate in a gas-liquid system. A full understanding of the mass transfer/mixing mechanism is not yet available, and therefore the selection of the optimum operating speed remains primarily a matter of experience. Before concluding this section, it is appropriate to indicate typical power consumptions in kW/m3 of liquid for various duties, and these are shown in Table 7.2. 

Semi)batch Continuous Kinetics rate Mass transfer Mixed, mass Kinetics rate Mass transfer... 

Computational fluid dynamics involves the analysis of fluid flow and related phenomena such as heat and/or mass transfer, mixing, and chemical reaction using numerical solution methods. Usually the domain of interest is divided into a large number of control volumes (or computational cells or elements) which have a relatively small size in comparison with the macroscopic volume of the domain of interest. For each control volume a discrete representation of the relevant conservation equations is made after which an iterative solution procedure is invoked to obtain the solution of the nonlinear equations. Due to the advent of high-speed digital computers and the availability of powerful numerical algorithms the CFD approach has become feasible. CFD can be seen as a hybrid branch of mechanics and mathematics. CFD is based on the conservation laws for mass, momentum, and (thermal) energy, which can be expressed as follows ... 

Liquid-Liquid Mass Transfer Mixing and Emulsions... 

Buckland, B.C., Gwewonyo, K., DiMasi, D., Hunt, G., Westerfield, G., and Nienow, A.W. (1988) Improved performance in viscous mycelial fermentations by agitator retrofitting. BiotechnoL Bioertg., 31, TS7—H2. Heijnen, J.J. and Van t Riet, K. (1984) Mass transfer, mixing and heat transfer phenomena in low viscosity bubble column reactors. Chetn. Eng. /, 28, B21-B42. 

Simulation of mrbnlent flnid mechanics, mass transfer, mixing, and chemical reaction reqnires the nse of one (typically differential) balance equation for each... 

Flow Rate (Q). Volume of fluid, whieh passes through a given area per unit of time. Flow rate determines the hydraulie retention time, directly affects mass transfer, mixing patterns and granule formation and may inerease shear stress on the eells (Villadsen et al., 2011 Taweel et al., 2012). Q [m h ]. 

HeijnenJJ Van t Riet K Mass transfer, mixing and heat transfer phenomena in low viscosity bubble column reactors, Chem EngJ 28 B21-B42, 1984. 

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