Cyclone mixer

Cyclone mixers give a rotational flow field [109], The corresponding formation of vortex patterns is another way of laminating and focusing streams. It is hoped that by folding of the vortices, thinning of the lamellae can be achieved, with an increase of residence time in the mixer [131]. A full rotation should halve the lamellae width. Hence the optimization parameter may be to have as many rotations as possible. 

This cyclone mixer comprises a spherical mixing chamber with 16equispaced nozzles which introduce the feeds tangentially at high (m s-1) fluid velocity [109] (see also [132]). 

This cyclone mixer comprises a cylindrical mixing chamber with many nozzles, arranged on the circular arc of the chamber (see Figure 1.113) [131]. At the the center of the floor of the chamber an outlet hole collects the multi-laminated streams. 

Figure 1.113 Cyclone mixer design with tangential inlets only.

Figure 1.114 Schematic of the cyclone mixer design (left) and streamline indicating the rotational flow field in the cyclone micro mixer [109] (by courtesy of Kluwer Academic Publishers).

Hardt, S., Dietrich, T., Freitag, A., Hessel, V., Lowe, H., Hofmann, C., Oroskar, A., Schonfeld, F., Vanden Bussche, K., Radial and tangential injection of liquid/liquid and gas/liquid streams and focusing thereof in a special cyclone mixer, in Proceedings of the 6th International Conference on Microreaction Technology, IMRET 6 (11-14 March 2002), AIChE Pub. No. 164, New Orleans, 2002, 329-344. 

Cyclone mixers can be made by focused injection of the fluids to be mixed in radial and tangential streams. Hardt et al. [77] have produced a CFD model of this type of mixer and optically verified its performance (Fig. 7.5). 

Figure 2.11 Schematic representation of fluid-fluid microstructured reactors (a micromixer settler b cyclone mixer c interdigital mixer d microchannel with partial overlap e microchannel with membrane or metal contactor f microchannels...

The selectivity of bromination of 1,3,5-trimethoxybenzene in a flow microreactor [8] depends on the total flow rate, when a less effective micromixer such as Swagelok T-mixer is used (Fig. 7.10). Monobromination product and dibromina-tion product are formed in almost 1 1 ratio at low flow rates. When a more effective micromixer such as IMVT cyclone mixer is used, the selectivity does not depend on the total flow rate and the highest monobromination/dibromination ratio of 100 is obtained. 

Magnetic pulley, conveyors, and elevators, rotary cooler, screening, crusher-mixer Particulates (dust) Exhaust system, cyclone, and baghouse... 

All the driers discussed above are unsuitable for mixtures with a high liquid proportion (slurries). For such mixtures spray driers (see Fig. 7.2-11) or cyclone driers (see Fig. 7.2-12) are effective. In the former the sluri-y is injected into the drier by a nozzle that atomizes the suspension. Small droplets fall down countercurrently to the hot gas that rises in the conical drier zone. In cyclone driers the sluriy and the hot gas flow cocurrently. Driers of both kinds are characterized by short residence times. Therefore, they are particularly suitable for temperature sensitive products. A significant proportion of driers of all kinds, appropriately modified, can also be operated as solids mixers and/or granulators. 

Mixer 49 [M 49] Cyclone Laminating Micro Mixer, Tangential Injection (I)... 

Mixer type Cyclone laminating Cover material Pyrex... 

Mixer type Cyclone laminating micro mixer, tangential injection Mixing chamber diameter 5 mm... 

Figure 1.115 Top photographs of vortex-flow pattern formation at various flow rates when contacting water and dyed water (acid blue) solutions in the tangential-flow cyclone micro mixer. Bottom comparison of the experimentally derived image of one vortex pattern with the predicted image by CFD simulation [131] (source IMM).

The separated crystalline perborate is dried in a current of air preheated in a heater to 60—70 °C. The Biittner dryer is very suitable for this operation. The dry perborate powder entrained is separated from the air in a cyclone, then homogenized in mixers and finally soreened. 

Fig. 12.9. Flow diagram for manufacture of cellulose acetate yarn (1) wood pulp (2) attrition mill (3) cyclone (4) 35% acetic acid (5) pretreater (6) magnesium acetate solution (7) precooled acetylation mix (8) sulfuric acid (9) acetylator (10) ripener (11) steam (12) blender (13) precipitator (14) dilute acetic acid (15) hammer mill (16) water (17) rotary screen washer (18) squeeze rolls (19) drying oven (20) blender (21) storage bins (22) silos (23) weight bins (24) acetone (25) wood pulp (26) pigment (27) mixers (28) hold tanks (29) filter press (30) pump (31) filter (32) air (33) jet (34) acetone recovery (35) oiling wheel (36) feed roll (37) bobbin (38) inspection.

To meet the supercritical conditions more suitable a mixer-settler unit has been developed by Schaffner [2], A regenerative pump was used as mixer to achieve an intense contact between the two phases and to create a large mass transfer surface area. This type of pump is capable of conveying gases as well as liquids and creates a high pressure difference which is used to separate the phases in the following fluid cyclone (fig. 1). 

The mechanical ways of foam breakdown are realised by various rotating devices (mixers, disks, centrifuges, propellers, etc.) or by employing stream of air, vapour or liquid or by running the foam through cyclones and narrow gaps [1,2]. In all these cases the liquid outflow from the foam is accelerated which creates critical deformations and stresses in films and other foam elements. A convenient classification of the mechanical means of foam breakdown and the methods designing such mechanical devices are considered in [3]. The... 

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