Mixing sections

Flare smoke suppression system consisting of an air duct mixing section, air nozzle ring header and associated duct work from ground level to fire tip. 

In commercial extruders, additional zones may be included to improve the quality of the output. For example there may be a mixing zone consisting of screw flights of reduced or reversed pitch. The purpose of this zone is to ensure uniformity of the melt and it is sited in the metering section. Fig. 4.4 shows some designs of mixing sections in extruder screws. 

Dampers in air handling units and air distribution systems Attention has to be paid to reducing the leakages, in accordance with EN 1751. Dampers used in mixing sections of air-handling units must fulfill additional requirements, in accordance with prEN 13053. 

Air terminal unit assembly The air terminal unit, consisting of casing, mixing section, flow control, heating, cooling, filters, fans, sound attenuators, etc. 

Mixing section of an ATD A section in which two air streams of different temperatures or moisture content are damper controlled to provide a given flow rate before mixing occurs. 

Mixing section of an AHU A section where outdoor airflow and the recirculation airflow are mixed in a controlled manner. 

Experimental setup and procedures. The experimental setup for N2O decomposition consisted of a gas mixing section, a reactor and a gas analysis section. A quartz fixed bed reactor of 5 mm I.D. was used, containing 20 mg of catalyst (106-212 mm) diluted with... 

The module system consists of three ideally mixed sections, separated by two membranes. Overall steady-state balances can be used to check the solution and are as follows ... 

Erwin, L Theory of mixing sections in single screw extruders. Polym. Eng. Sci. 18, 7, 572-576 (1978). 

If a sieve, dual-flow, or grid-tray column is used, the only way to operate the column in a stable manner at the low initial flow rates is to blank offpart of the trays. This increases the vapor velocity through the mixing section, and assmes good contact and an efficient separation. These blanks can be removed at the time of the expansion. 

Fig. 1. General microreactor for organic transformations as the round-bottom flask equivalent. The microreactor incorporates (i) a laminar flow mixing section of separate streams, exemplified for glycosylation, (ii) reaction channel, inlet for quench, and an outlet (Ratner et al. 2005 Murphy 2006)...

The imperfect mixing in a chemical reactor can be modeled by splitting the total volume into two perfectly mixed sections with circulation between them. Feed enters and leaves one section. The other section acts like a side-capacity element. 

A deadtime clement is basically a distributed system. One approximate way to get the dynamics of distributed systems is to lump them into a number of perfectly mixed sections. Prove that a scries of N mixed tanks is equivalent to a pure deadtirae as N goes to infinity. 

Numerous mixing sections are available commercially from many manufacturers. Only the most commonly used mixers will be discussed in this section. 

Gregory, R.B., Mixing Section for Extruder Feed Screw, US Patent 3,788,614 (1974)... 

Tadmor, Z. and Klein, T, Design of Certain Fluted Mixing Sections of Extruder Screws, Polym. Eng. Set, 13, 382 (1973)... 

Mixing sections are cut into the biiiet next using the miiiing machine and iathe combination, as shown in Fig. 10.29(a). Depending on the mixer design, cutting these sections tends to be more time consuming. 

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