Liquid-solid cyclones

Liquid cyclones can be used for the classification of solid particles over a size range from 5 to 100 jim. Commercial units are available in a wide range of materials of 

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FIG. 20-45 Closed -circuit wet grinding with liquid-solid cyclone. [Tonty, Pit Quarry (Fehtuaty-March L95.9).]... 

Figure 4-52B. Liquid-solids cyclone fabricated to resist corrosion...

Figures 20-43 to 20-44 illustrate single-stage and two-stage closed-circuit wet-grinding systems. The circuits of Fig. 20-59 may also be used as a closed-circuit wet-grinding system incorporating a liquid-solid cyclone as the classifier.

Fitch and Johnson, Controlling Separation in Liquid-Solid Cyclones, Chem. Eng., June, 1952, p. 172. 

Centrifugal Separation Centrifugal force can be utilized to enhance particle collection to several hundredfold that of gravity. The design of cyclone separators for dust removal is treated in detail in Sec. 17 under Gas-Solids Separations, and typical cyclone designs are shown in Fig. 17-43. Dimension ratios for one family of cyclones are given in Fig. 17-36. Cyclones, if carefully designed, can be more efficient on hquids than on solids since liquids coalesce on capture and are easy to drain from the unit. However, some precautions not needed for solid cyclones are necessary to prevent reentrainment. 

Figure 4-52A. Liquid-solids removal cyclones. Feed enters tangentially along sidewall. By permission, Krebs Engineers.

Lines in vacuum service, 135—141 Line symbols, 17, 23 Numbering, 23 Lined centrifugal pumps, 171 Liquid-solid particle, separators, 228 Baffle type specifications, 248 Baffle type, 247, 248 Centrifugal, 256, 259-261 Chcvron-vanc, 248, 235 Comparison chart, 230 Cyclone, 259 Specification form, 268 Vane, 259 Wire mesh, 246 York-vane, 248 Low pressure storage... 

Cyclones can be used for the classification of solids, as well as for liquid-solid, and liquid-liquid separations. The design and application of liquid cyclones (hydrocyclones) is discussed in Section 10.4.4. A typical unit is shown in Figure 10.3. 

Cyclone separators are also frequently used for gas-liquid separation. They can be designed using the same methods for gas-solids cyclones. The inlet velocity should be kept below 30 m/s to avoid pick-up of liquid form the cyclone surfaces. 

Hydroclones were introduced in 1891 to remove sand from water. They function like a gas-solid cyclone, have no moving parts, and rely on centrifugal force for separation, clarification, and dewatering processes. Hydroclones find use in concentrating slurries, in classifying solids in liquid suspensions, and in washing solids. They may be used alone or in conjunction with clarifiers, thickeners, or filters (Besendorfer, 1996). 

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