Liquid mixing systems

Holland, F.A. Scale-Up of Liquid Mixing Systems, Chemical Engineering, Sept. 17, 1962, p. 179. Chen, S.J., MacDonald, A.R. Motionless Mixers for Viscous Polymers, Chemical Engineering, Mar. 19, 1973, p. 105. 

Agitator tip speeds uT given by equation 5.3 are commonly used as a measure of the degree of agitation in a liquid mixing system. 

In the design of liquid mixing systems the following dimensionless groups are of importance. 

In liquid mixing systems, baffles are used to suppress vortexing. Since vortexing is a gravitational effect, the Froude number is not required to describe baffled liquid mixing systems. In this case the exponent y in equations 5.17 and 5.18 is zero and FryM = 1. 

The Weber number for mixing WeM is only of importance when separate physical phases are present in the liquid mixing system as in liquid-liquid extraction. 

The principle of similarity [Holland (1964), Johnstone and Thring (1957)] together with the use of dimensionless groups is the essential basis of scale-up. The types of similarity relevant to liquid mixing systems together with their definitions are listed as follows. 

Equation 5.17 for liquid mixing systems is in the same form as equation 5.35... 

The scale-up of liquid mixing systems can be divided into two categories the scale-up of process result and the scale-up of power data. 

Multi-phase mixing is often seen in industries. In general, the distribution of not only the dispersed phase but also the continuous phase depends on the local position in the equipment in the case of a multi-phase operation such as gas-liquid mixing system, liquid-liquid mixing system, solid-liquid mixing system, and gas-liquid-solid mixing system. In order to evaluate the mixing state in such systems, both the dispersed phase and continuous phase should be considered. 

Fig. 2 A typical high efficiency gas-liquid mixing system. (View this art in color at www.dekker.com.)...

In liquid systems, we can suppress the effect of the Froude number by using baffles to eliminate vortexing and hence the gravitational effects. The Weber number is of some importance only when separate physical phases aie present in the liquid mixing system. 

Interaction is accompanied by formation of the heteromolecular associates. It can be demonstrated by analysis of volumetric equations for the liquid mixed systems, data on volume compression, i.e., positive density deviation from additivity rule, and hence negative deviations of experimental specific molar volume from partial molar volume additivity rule. 

This review is devoted to inspection of the availablity of some most outstanding relationships between viscosity of real liquid mixed systems and the independent... 

Thermosets are mainly viscous liquid resins, presenting their own compounding requirements. Liquid mixing systems of varying degrees, from the most basic to highly sophisticated are used, depending on the type of resin, additives, and volume output required. 

Fukaya, Y., Sekikawa, K., Murata, K, Nakamura, N. Ohno, H. (2007). Miscibility and Phase Behavior of Water-Dicarboxylic Acid Type Ionic Liquid Mixed Systems. Chemical Communications, No. 29, pp. 3089-3091, ISSN 1359-7345 Fukumoto, K Ohno, H. (2007). LCST-Type Phase Changes of a Mixture of Water and Ionic Liquids Derived from Amino Acids. Angewandte Chemie-International Edition, Vol. 46, No. 11, pp. 1852-1855, ISSN 1433-7851... 

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