Discharge section

After the flow has been introduced into the compressor and has been acted on by one or more stages, it must be extracted. Because there is a relatively large amount of velocity head available in the stream, care must be used when designing the discharge section to keep the head loss low and maintain overall efficiency. The flow from the last stage is gath-... 

Cooling of the pellets begins at the outlet of the reactor. Nitrogen enters the reactor cold and the pellets are cooled in the reactor discharge section to ca. 180 °C. The pellets then pass into a fluid bed cooler, where they are cooled within 5 min to typically less than 60 °C by fresh air. 

The metering section of the screw presented above was simulated at 120 kg/h and a discharge pressure of 6 MPa. The screw had to be rotated at a speed of 56 rpm to obtain 120 kg/h. The barrel temperatures were 160, 220, and 275 °C for the feed section through the discharge section, respectively. The simulated axial pressure and temperature are shown in Fig. 9.3. 

The devolatization sections and the discharge section up to the screw tip contain predominantly conveying elements that are partially filled in the devolatization area and completely filled in the pressure build-up area. A homogenous melt is generally assumed in these processing steps where viscosity is altered up to the tip of the screw, depending on the temperature evolution. 

The spinneret is a type of die principally used in fiber manufacture. It is usually a metal plate with many small holes (or oval, etc.) through which a melt is pulled and/or forced. They enable extrusion of filaments of one denier or less. Conventional spinneret orifices are circular and produce a fiber that is round in cross section. They can contain from about 50 to 110 very small holes. A special characteristic of their design is that the melt in a discharge section of a relatively small area is distributed to a large circle of spinnerets. Because of the smaller distance in the entry region of the distributor, dead spaces are avoided, and the greater distance between the exit orifices makes for easier threading.143... 

The total power requirements for pumping are calculated by adding the hydraulic and the viscous power requirements. The former can be estimated from the MEB equation written for the work input, — W. We note that p — p2 and that Ef includes not only the friction losses on the discharge section but also the inlet section. The former was, as stated earlier, estimated to be 329.0 J kg , while the latter was estimated to be... 

Centrifuge Dryers Usually they are batch or continuous filtering centrifuges (Sec. 18, "Liquid-Solid Operations and Equipment ) with hot air being blown over the solids in the discharge section. Manufacturers include Heinkel and Bird-Humboldt. 

FIGURE 22.42 Cycles for disc and drum filters show cake formation, suction, washing, drainage, and discharge sections. 

Excitation by microwave frequency (245O MHz). Ozy gen under 1 torr pressure is passed through a quartz tube which is part of the discharge section which is connected to electrodeless microwave generator (Fig.1). 

The siuface kinetics of etching (Section 8.2.7) is controlled by concentrations of ions and active neutrals near the surface. Determination of these parameters reqttires a detailed consideration of etching discharges (Sections 8.2.8 and 8.2.9). Some nseful relations, however, can be derived from general kinetics of the low-pressme discharges applied for etching. In this section, we make such estimations for the concentration and flux of ions concentration and flux of neutral chemically active etchants will be estimated in the next section. A balance of charged particles in plasma between electrodes with area A (characteristic radius R) and narrow gap / between them (/ R), controlled by ionization and losses to the electrodes,... 

Multiple-screw extruders can involve either two screws (twin-screw design) or four screws. A typical four-screw extruder is a two-stage machine, in which a twin-screw plasticating section feeds into a twin-screw discharge section located directly below it. The multiple screws are generally sized on output rates (Ib/h) rather than on L/D ratios or barrel diameters. 

An electrostatic discharge (Section 10.16.1) with an electric arc as contact medium may imply very high current densities on the affected area. 

The hydrogen chiller resembles the chlorine coolers in its design. It is mounted vertically, with downward flow of the gas. The bottom head serves as a gas-liquid separator, and the condensate flows on to a receiver. The condensate separates into two phases, and the receiving vessel should be designed for easy removal of the metal. The water will be contaminated with mercury and so must be returned to the process or treated carefully before being discharged (Section 16.5.5.3). 

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