Bladed rotor separator

Fig. 30b Bladed rotor separator, with drive, as an independent classifying unit fed through a riser duct (Loesche GmbH)...

The circulating air separator (as a generic designation) differs from the static separator and the bladed rotor separator in some important respects ... 

Rotor blades also form an element of several external classifiers that are used in closed-circuit dry milhng. These are generally called mechanical air separators or classifiers. Examples are the Whirlwind classifier Sturtevant Inc.), the Gayco centrifugal separator Universal Road Machinery Co. (see Fig. 20-41), and the whizzer separator Raymond Division of Combustion Engineering Inc.). 

Some mechanical air classifiers are designed so that the fine product must pass radially inward through rotor blades instead of spirally moving across them as with whizzer blades. Examples are the Mikron separator Hosokawa Micron Powder Systems Div.), Sturtevant Side Draft separator, and the Majac classifier shown attached to the Majac jet mill (Fig. 20-55). 

The rotor assembly shall have a unique identifieation number permanently marked on the shaft. Blade and disk residual life eurves shall be provided by the Seller. The disk/shaft attaeh-ment shall be redundant so that if the primary torque transmission path fails, a seeondary path will prevent separation of the disk from the shaft. 

Other suggestions that address gas flow deviation include a retrofit of the stator-nozzle assembly or replacing rotors with shorter blades. However, it is easier to increase volume flow by lowering inlet pressure. Increased capacity of the third-stage separator and the auxiliary equipment avoids the possibility that excess catalyst will pass through the equipment. 

The rotor or impeller of the radial-inflow turbine eonsists of a hub, blades, and in some eases, a shroud. The hub is the solid axisymmetrieal portion of the rotor. It defines the inner boundary of the flow passage and is sometimes ealled the dise. The blades are integral to the hub and exert a normal foree on the flow stream. The exit seetion of the blading is ealled an exdueer and it is eonstrueted separately like an indueer in a eentrifugal eompressor. The exdueer is eurved to remove some of the tangential veloeity foree at the outlet. 

This type of unit, known also as a thin-film evaporator is shown in Figure 14.24. It consists of a vertical tube, the lower portion of which is surrounded by a jacket which contains the heating medium. The upper part of the tube is not jacketed and this acts as a separator. A rotor, driven by an external motor, has blades which extend nearly to the bottom of the tube, mounted so that there is a clearance of only about 1.3 mm between their tips and the inner surface of the tube. The liquor to be concentrated is picked up as it enters by the... 

When a high degree of shear on small liquid volume is desired, a rotor-stator stirrer is used (see Fig. 4). This stirrer consists of a blade or paddle stirrer enclosed by a ring of baffles. This type of stirrer thus alleviates the need for separate baffles in the vessel. This stirrer is not useful for biological reactors, but finds special use in polymeric reactors containing non-Newtonian liquids. 

An entrainment separator is attached to the scrubber near the exit to prevent spray carryover. This design is limited in the dust loading because the wear on the rotor blades is high due to the solids. 

The turbine setting, see Fig. X-15, incorporates the state-of-the-art in moisture separation systems for turbines [X-7 and X-8]. The low-pressure cylinder incorporates a dedicated next to last separation stage, which has moisture collection grooves on the convex surface of the peripheral part of a turbine rotor blade. It also incorporates a roof-type shroud and an ejector-type moisture trap. The next to last stages of the high- and medium-pressure turbine parts provide for the dehydration of steam, which is accomplished through the use of a jet and the turbine rotor blades of special design. 

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