Static in-line mixer

Minor ingredients include excess fatty acids, preservatives, and potentially other synthetic surfactants. Alternatively, mixing can be achieved through the use of in-line static mixers, with the accurate addition of the minors into a flowing stream of the wet soap. 

Figure 20. Example of an in-line static mixer for polyelectolyte additions.

To improve the mixing quality in the tubular reactor, Kenics type in-line static mixer reactor was employed. The in-line static mixers were designed to mix two or more fluids efficiently since an improved treinsport process such as flow division, radial eddying, flow constriction, and shear reversal eliminated the gradients in concentration, velocity and temperature. However, only 70 % conversion was achieved with one Kenics mixer unit. As shown in Table 2, five mixer units were required to achieve the maximum conversion. 

Table 2. Production of B0C2-AMP with Kenics in-line static mixer reactor...

The high pressure continuous reactor consists of five Kenics type in-line static mixers, that were connected in series [3]. Each reactor unit has 27 Kenics elements and dimensions of 19 cm tube length and 3.3 mm inner diameter. Acetonylacetone and 1 % NaOH aqueous solution were pumped into the in-line static mixer reactor using two independent HPLC pumps. The in-line static mixer reactors were immersed in a constant temperature controlled oil bath at 200 °C so that the reaction mixture was heated to the reaction temperature. When the reaction was completed, the fluid was cooled down rapidly in a constant temperature cold bath at 0 °C. At the end of the cooling line, a backpressure regulator was placed to allow experiments to be run at 34 bar. 

Figure 7.4c shows an in-line static mixer. Dispersion is usually promoted by repeatedly changing the direction of flow locally within the mixing device as the liquids are pumped through. This will give a good approximation to plug-flow in both phases in cocurrent flow. As with gas-liquid reactors, static mixers are particularly suitable when a short residence time is required. 

Figure 18. Pronk static in-line static mixer.

Degumming. Crude coconut oil is continuously heated to 80-90°C, and 85% phosphoric acid at a range of 0.05-0.10% by volume of feedstock is dispersed in the oil via an in-line static mixer. The mixture is conveyed into a coagulation tank and agitated for 20-30 min. 

FIG. 14.1 (a) Turbulent flow configuration in-line static mixer. (Courtesy of LIGHT-... 

NIN, a unit of General Signal Corporation.) (b) In-line static mixer with mixing elements. (Courtesy of Chemineer, Inc.)... 

S. T. Lin, L. T. Fan, and N. Z. Azer, Augmentation of Single Phase Convective Heat Transfer With In-Line Static Mixers, Proc. 1978 Heat Transfer Fluid Mech. Inst., pp. 117-130, Stanford University Press, Stanford, CA, 1978. 

Figure 11.20 Precipation stage in continuous plasma fractionation system (A) alcohol tank (B) buffer tank (C) plasma tank (D) suspension tank (E) product receiving tank (F) tubular cooler (G) in-line static mixer (H) pH ananlyzer/recorder (I) level controller (J) pH probes (K) agitator. (1) Metering pump for suspension recirculation (2) metering pump for feed (3) metering pump for alcohol (4) metering pump and controller for buffer. (Reprinted with permission of J. Wiley Sons, Inc. from Chang, C.E., Biotech. Bioeng. 31, pp. 841-847. J. Wiley Sons, Inc., 1988.)...

Impellers 120 Jet mixers 125 In-line static mixers 126 In-line dynamic mixers 127 Mills 128... 

In areas such as miscible liquid blending, the formation of emulsions, solid dispersions such as paints, and dry powder mixing, it is understandable, therefore, that several criteria have been developed to assess mixture quality . It is unfortunate that of the many definitions presently available for mixture quality, in solid or liquid mixtures, none is universally applicable. In the case of powder mixing, further details may be found in Chapter 2, while for liquid mixing more information is presented in Chapters 8 and 10 for mechanically agitated vessels. Chapter 9 for Jet mixers and Chapter 12 for in-line static mixers. 

In recent years the in-line static mixer has been adopted for a large number of blending and dispersing operations. Many in-line mixers are now commercially available. The geometrical details of these devices differ greatly but the principles of operation are basically the same in each case. 

For blending and dispersing duties, in-line static mixers offer the advantage of continuous operation and small working volume. Units are available to fit... 

Figure 7.9 Laminar blending in a Chemineer-Kenics in-line static mixer simplified mixing mechanism...

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